bcm2835-sdhost: gradually increase polling interval #1492
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| while (time_before(jiffies, wait_max)) { | ||
| spin_unlock_irqrestore(&host->lock, *irq_flags); | ||
| usleep_range(1, 10); | ||
| usleep_range(usleep_min, usleep_min * 8UL); | ||
| usleep_min = max(256UL, usleep_min * 4UL); |
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If you want to cap the value at 256 you need to use min here.
And remember the value is multiplied by 8 so this will be 2048us.
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Thanks for catching that :) 1 8 Ahmet |
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I can't see a justification for the factor of 8 scaling on the sleep range. Either a factor of 2 or a factor of 4 would make sense, but 8 seems excessive. |
With the Compute Module I get timeout's while initializing the eMMC: mmc0: command never completed. And the system won't boot properly. With this patch it boots every single time successfully and won't ever show the above error. Sometimes commands need at least 150us to complete. Instead of polling every 1us, gradually increase the interval with each iteration until 256us is reached and continue polling every 256us. Gradually here is actually times four with each iteration as just doubling sometimes still leads to an "command never completed". Signed-off-by: Ahmet Inan <[email protected]>
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I was thinking the same :) |
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I'd like to investigate this some more before making a change that could affect all users. Thanks for your efforts so far. |
pelwell
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Sep 5, 2016
The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
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I think I now understand the reason why this commit made the sdhost driver more reliable on the Compute Module, and I have an alternative fix. I found that the interface sometimes sets the FAIL flag before clearing the NEW flag. If the polling loop (there is no suitable interrupt...) exits when the FAIL flag is set, the following check that the NEW flag is clear can fail. A side-effect of increasing the polling interval is to decrease the chance that the FAIL flag is checked before the NEW flag has had chance to clear. I think it is safe, and probably wise, to use an exponential polling interval anyway, but for now I have left it unchanged to ensure that my understanding of the problem is correct. |
popcornmix
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Sep 5, 2016
The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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Sep 5, 2016
The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
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I can test your patch next week at work. |
popcornmix
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See: raspberrypi/linux#1574 kernel: bcm2835-sdhost: Don't exit cmd wait loop on error kernel: BCM270X_DT: Use bcm2835-sdhost on Compute Module See: raspberrypi/linux#1492
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See: raspberrypi/linux#1574 kernel: bcm2835-sdhost: Don't exit cmd wait loop on error kernel: BCM270X_DT: Use bcm2835-sdhost on Compute Module See: raspberrypi/linux#1492
popcornmix
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Sep 7, 2016
The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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Sep 7, 2016
The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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Sep 7, 2016
The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
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Awesome, your patch indeed fixes the problem. |
popcornmix
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Sep 14, 2016
The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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Sep 15, 2016
The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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Sep 24, 2016
The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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Sep 29, 2016
The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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Sep 30, 2016
The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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Oct 3, 2016
The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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Oct 9, 2016
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]>
popcornmix
pushed a commit
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Nov 11, 2024
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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Nov 18, 2024
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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Nov 18, 2024
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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Nov 18, 2024
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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Nov 25, 2024
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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Dec 9, 2024
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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Dec 10, 2024
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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Dec 16, 2024
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
popcornmix
pushed a commit
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Dec 16, 2024
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
popcornmix
pushed a commit
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Dec 20, 2024
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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Jan 6, 2025
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
popcornmix
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Feb 3, 2025
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
popcornmix
pushed a commit
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Feb 3, 2025
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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Feb 17, 2025
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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Feb 28, 2025
BCM2835 has two SD card interfaces. This driver uses the other one. bcm2835-sdhost: Error handling fix, and code clarification bcm2835-sdhost: Adding overclocking option Allow a different clock speed to be substitued for a requested 50MHz. This option is exposed using the "overclock_50" DT parameter. Note that the sdhost interface is restricted to integer divisions of core_freq, and the highest sensible option for a core_freq of 250MHz is 84 (250/3 = 83.3MHz), the next being 125 (250/2) which is much too high. Use at your own risk. bcm2835-sdhost: Round up the overclock, so 62 works for 62.5Mhz Also only warn once for each overclock setting. bcm2835-sdhost: Improve error handling and recovery 1) Expose the hw_reset method to the MMC framework, removing many internal calls by the driver. 2) Reduce overclock setting on error. 3) Increase timeout to cope with high capacity cards. 4) Add properties and parameters to control pio_limit and debug. 5) Reduce messages at probe time. bcm2835-sdhost: Further improve overclock back-off bcm2835-sdhost: Clear HBLC for PIO mode Also update pio_limit default in overlay README. bcm2835-sdhost: Add the ERASE capability See: #1076 bcm2835-sdhost: Ignore CRC7 for MMC CMD1 It seems that the sdhost interface returns CRC7 errors for CMD1, which is the MMC-specific SEND_OP_COND. Returning these errors to the MMC layer causes a downward spiral, but ignoring them seems to be harmless. bcm2835-mmc/sdhost: Remove ARCH_BCM2835 differences The bcm2835-mmc driver (and -sdhost driver that copied from it) contains code to handle SDIO interrupts in a threaded interrupt handler rather than waking the MMC framework thread. The change follows a patch from Russell King that adds the facility as the preferred way of working. However, the new code path is only present in ARCH_BCM2835 builds, which I have taken to be a way of testing the waters rather than making the change across the board; I can't see any technical reason why it wouldn't be enabled for MACH_BCM270X builds. So this patch standardises on the ARCH_BCM2835 code, removing the old code paths. bcm2835-sdhost: Don't log timeout errors unless debug=1 The MMC card-discovery process generates timeouts. This is expected behaviour, so reporting it to the user serves no purpose. Suppress the reporting of timeout errors unless the debug flag is on. bcm2835-sdhost: Add workaround for odd behaviour on some cards For reasons not understood, the sdhost driver fails when reading sectors very near the end of some SD cards. The problem could be related to the similar issue that reading the final sector of any card as part of a multiple read never completes, and the workaround is an extension of the mechanism introduced to solve that problem which ensures those sectors are always read singly. bcm2835-sdhost: Major revision This is a significant revision of the bcm2835-sdhost driver. It improves on the original in a number of ways: 1) Through the use of CMD23 for reads it appears to avoid problems reading some sectors on certain high speed cards. 2) Better atomicity to prevent crashes. 3) Higher performance. 4) Activity logging included, for easier diagnosis in the event of a problem. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Restore ATOMIC flag to PIO sg mapping Allocation problems have been seen in a wireless driver, and this is the only change which might have been responsible. SQUASH: bcm2835-sdhost: Only claim one DMA channel With both MMC controllers enabled there are few DMA channels left. The bcm2835-sdhost driver only uses DMA in one direction at a time, so it doesn't need to claim two channels. See: #1327 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Workaround for "slow" sectors Some cards have been seen to cause timeouts after certain sectors are read. This workaround enforces a minimum delay between the stop after reading one of those sectors and a subsequent data command. Using CMD23 (SET_BLOCK_COUNT) avoids this problem, so good cards will not be penalised by this workaround. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Firmware manages the clock divisor The bcm2835-sdhost driver hands control of the CDIV clock divisor register to matching firmware, allowing it to adjust to a changing core clock. This removes the need to use the performance governor or to enable io_is_busy on the on-demand governor in order to get the best SD performance. N.B. As SD clocks must be an integer divisor of the core clock, it is possible that the SD clock for "turbo" mode can be different (even lower) than "normal" mode. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Reset the clock in task context Since reprogramming the clock can now involve a round-trip to the firmware it must not be done at atomic context, and a tasklet is not a task. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Don't exit cmd wait loop on error The FAIL flag can be set in the CMD register before command processing is complete, leading to spurious "failed to complete" errors. This has the effect of promoting harmless CRC7 errors during CMD1 processing into errors that can delay and even prevent booting. Also: 1) Convert the last KERN_ERROR message in the register dumping to KERN_INFO. 2) Remove an unnecessary reset call from bcm2835_sdhost_add_host. See: #1492 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: mmc_card_blockaddr fix Get the definition of mmc_card_blockaddr from drivers/mmc/core/card.h. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: New timer API mmc: bcm2835-sdhost: Support underclocking Support underclocking of the SD bus in two ways: 1. using the max-frequency DT property (which currently has no DT parameter), and 2. using the exiting sd_overclock parameter. The two methods differ slightly - in the former the MMC subsystem is aware of the underclocking, while in the latter it isn't - but the end results should be the same. See: #2350 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Add include highmem.h (needed for kmap_atomic) is pulled in by one of the other include files, but only with some CONFIG settings. Make the inclusion explicit to cater for cases where the CONFIG setting is absent. See: #2366 Signed-off-by: Phil Elwell <[email protected]> mmc/bcm2835-sdhost: Recover from MMC_SEND_EXT_CSD If the user issues an "mmc extcsd read", the SD controller receives what it thinks is a SEND_IF_COND command with an unexpected data block. The resulting operations leave the FSM stuck in READWAIT, a state which persists until the MMC framework resets the controller, by which point the root filesystem is likely to have been unmounted. A less heavyweight solution is to detect the condition and nudge the FSM by asserting the (self-clearing) FORCE_DATA_MODE bit. N.B. This workaround was essentially discovered by accident and without a full understanding the inner workings of the controller, so it is fortunate that the "fix" only modifies error paths. See: #2728 Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Fix warnings on arm64 Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Allow for sg entries that cross pages The dma_complete handling code calculates a virtual address for a page then adds an offset, but if the offset is more than a page and HIGHMEM is in use then the summed address could be in an unmapped (or just incorrect) page. The upstream SDHOST driver allows for this possibility - copy the code that does so. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fix DMA channel leak on error/remove Signed-off-by: Phil Elwell <[email protected]> mmc: bcm2835-sdhost: Support 64-bit physical addresses Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Replace obsolete struct timeval struct timeval has been retired due to the impending linux 32-bit tv_sec rollover (only 18 years to go) - timespec64 is the obvious replacement. Signed-off-by: Phil Elwell <[email protected]> mmc: sdhost: Pass DT pointer to rpi_firmware_get Using the rpi_firmware API as intended allows proper reference counting of the firmware device and means we can remove a downstream patch to the firmware driver. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use DT to configure logging Retrieve the system timer base address directly from DT. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Use phys addresses for slave DMA config Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]> bcm2835-sdhost: Fail gracefully with bad dtb The logging timestamps depend on the existence of a bcm2835-system-timer node. If this node doesn't exist, leave the logging disabled rather than crashing. Signed-off-by: Phil Elwell <[email protected]>
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With the Compute Module I get timeout's while initializing the eMMC:
mmc0: command never completed.
And the system won't boot properly.
With this patch it boots every single time successfully and won't ever
show the above error.
Sometimes commands need at least 150us to complete.
Instead of polling every 1us, gradually increase the interval with each
iteration until 256us is reached and continue polling every 256us.
Gradually here is actually times four with each iteration as just
doubling sometimes still leads to an "command never completed".
Signed-off-by: Ahmet Inan [email protected]