bootloader_jump doesn't work

[kejadlen]

I feel like I must be doing something wrong, but I can't get bootloader_jump to work. Is there anything else I need to do besides changing BOOTLOADER_SIZE in config.h and using the following code in the keymap?

if (id == TEENSY_KEY) {
    clear_keyboard();
    print("\n\nJump to bootloader... ");
    _delay_ms(250);
    bootloader_jump(); // should not return
    print("not supported.\n");
}

Source here, if that helps at all: https://github.com/kejadlen/tmk_keyboard/tree/master/keyboard/planckeus

I also inadvertently ran the bootloader jump with the wrong bootloader size before realizing that needed to be changed - would that have any effect on future uses of bootloader_jump?

[tmk]

I glanced over your codes; keymap and Makefile. It looks to me ok and should work.

And jummping wrong address won't have any permanent effect on hardware or firmware.

[kejadlen]

Ah, I didn't notice this in the output before:

keymap_default.c: In function 'action_function':
keymap_default.c:39:9: warning: implicit declaration of function 'bootloader_jump' [-Wimplicit-function-declaration]
         bootloader_jump(); // should not return
         ^

Could this be why it's not working?

[kejadlen]

Interestingly, the physical button doesn't work after I try to get into the bootloader via the action function. I need to unplug the USB cable, re-plug it back in, and then hit the physical button for it to do anything.

[tmk]

Weird, reset button should work all the time even if firmware goes mad.
I don't have Teensy to test at hand and don't know if bootloader_jump code really works for Teensy.

[tmk]

You can try this old code instead of current bootloader_jump().
https://github.com/kejadlen/tmk_keyboard/blob/master/common/avr/bootloader.c#L87

The old code is from PJRC article and expected to work with Teensy bootloader.
https://www.pjrc.com/teensy/jump_to_bootloader.html

[kejadlen]

Drat, forgot to mention that bootloader_jump works just fine on my Ergodox: https://github.com/kejadlen/tmk_keyboard/tree/master/keyboard/ergodox, so it seems the current code does at least work for the Teensy there.

[technomancy]

I can confirm this on my Teensy: https://github.com/technomancy/tmk_keyboard/commit/876f356900504a8d38af72c918c1373073df0cf3

[kejadlen]

@technomancy Does that SHIFT macro work? I'd love to get rid of the tons of fn_actions I have for shifted keys at the moment.

[technomancy]

It doesn't work, but I have a lead on how to make it work; see #184.

[technomancy]

@kejadlen bootloader_jump still isn't working for me, but I got the SHIFT macro working on my teensy2 branch.

[p3lim]

Add this to the top of the file where you're using bootloader_jump():

#include "bootloader.h"

Works fine for me on my Teensy2: p3lim/keyboard_firmware@5ad92cd

[kejadlen]

@p3lim Tried that, but it doesn't work for me.

[p3lim]

@kejadlen Any errors when compiling?

[kejadlen]

@p3lim No, it compiles just fine, but trying to use FN0 (the bootloader jump) freezes/crashes the keyboard so I need to reset it by pulling the USB plug.

[tmk]

What's your keyboard hardware in fact? and Which Teensy?
You said you can't use reset button when it freezes. Doesn't pushing reset button for long like 5-10 sec work for you?

Seems like it jumps wrong address and goes mad.

[kejadlen]

Using a Teensy 2.0. Pushing it for 5-10 seconds doesn't do anything either.

That sounds plausible to me. Still not sure what the difference is between what I'm doing and other Teensy 2.0 projects, though. (source)

[technomancy]

@kejadlen I got this working by just dumping in some code from pjrc.com: https://github.com/technomancy/tmk_keyboard/commit/ebb4f96b074e06be8ab3ee3727ad384f5b78f58b

Probably would be better if it were fixed properly inside the TMK common code, but this works for me.

[tmk]

Hmm, it smells like this line is fishy. Perhaps it can be compiled differently depending on compiler version?

https://github.com/tmk/tmk_keyboard/blob/master/common/avr/bootloader.c#L75

We should use assembly code fragment there?

[kejadlen]

Curiously, bootloader_jump works correctly on the Ergodox, which uses a Teensy 2.0 as well. I have no clue what the difference might be.

[kejadlen]

@technomancy Thanks, that workaround works for me as well.

Unfortunately, I'm fairly out of my depth here, but I'd be happy to investigate further if anyone has any suggestions for what I could do to provide more info.

[tmk]

I seems to me like GCC changed bahaviour somewhere in 4.8 or 4.7.

This C code is comipled with icall which requires _word address_ in GCC 4.8.1. Probably older compiler spits out assembly mnemonic requries _byte address_, though I confirmed yet.

EDIT: all AVR branch instructions take word address of ROM.

 ((void (*)(void))(BOOTLOADER_START))();

I think using inline assembler is safer again future compiler behaviour changes, like PJRC describes here. https://www.pjrc.com/teensy/jump_to_bootloader.html

asm volatile("jmp 0x7000");

Old LUFA document expects GCC uses byte address to jump.
http://www.fourwalledcubicle.com/files/LUFA/Doc/120730/html/_page__software_bootloader_start.html

New documents make use of word address with logical shift(>>1).
http://www.fourwalledcubicle.com/files/LUFA/Doc/140928/html/_page__software_bootloader_start.html

Similar icall and byte/word address problem:
http://www.avrfreaks.net/forum/dfu-bootloader-immediately-bails-out

[tmk]

TMK had refered to old wrong LUFA documentaion. Jump address should be word counted.
http://www.fourwalledcubicle.com/files/LUFA/Doc/120219/html/_page__software_bootloader_start.html

LUFA fixed it.
http://www.fourwalledcubicle.com/files/LUFA/Doc/140928/html/_page__software_bootloader_start.html
abcminiuser/lufa@c528263

GCC version is not related at all.

[tmk]

TMK fixed this problem at Sep 18, 2013 with this commit 0ca4150.

Make sure setting proper value to BOOT_LOADER_SIZE in Makefile.

# Boot Section Size in *bytes*
#   Teensy halfKay   512
#   Teensy++ halfKay 1024
#   Atmel DFU loader 4096       (TMK Alt Controller)
#   LUFA bootloader  4096
#   USBaspLoader     2048
OPT_DEFS += -DBOOTLOADER_SIZE=4096

[AxisRay]

I have the same problem.
It seems that GCC version is related.
there is a bug in gcc-avr
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=27192
I have a Teensy 2.0 ++ with chip AT90USB1286,and compile tmk with WinAVR (gcc-avr 4.3.3)
I should use

((void (*)(void))(BOOTLOADER_START))();

instead of

((void (*)(void))(BOOTLOADER_START/2))();//It doesn't work

but when I use gcc-avr 4.8.1 under ubuntu ,both of them don't work.
so I use the following code instead

asm volatile("jmp 0xFC00");//I don't know why not 0x1FC00

[tmk]

hmm, I have to check WinAVR again some time later. (TODO) EDIT: see below.

BOOTLOADER_SIZE for Teensy++2.0 is 2048 bytes, though some of my Makefiles say it is 1024 wrongly. Did you use correct size?

BTW, I confirmed the current code works on Teensy++2.0 with gcc 4.8.1/avr libc1.8.0.

[AxisRay]

Thanks for reply.
I have checked BOOTLOADER_SIZE,but It still doesn't work.(test with gcc 4.8.1/avr libc1.8.0.)
Well,maybe there is something wrong with my teensy.
I have no patient to figure out what going wrong with it,the inline assembler works well after all.
Anyway,Thanks for your firmware.It very useful for me.

[tmk]

Thanks.
You still have problem with GCC 4.8.1, this clearly indicate this is not related to GCC version.

I think WinAVR is not guilty.