Merge branch 'bugfix/fix_psram_access_faild_after_pd_cpu_wakeup_v4.4'…

… into 'release/v4.4'

fix(esp_pm): fix psram access failed after pd_cpu wakeup if uart driver driven console is used (backport v4.4)

See merge request espressif/esp-idf!27056

components/esp_pm/Kconfig

@@ -100,18 +100,28 @@ menu "Power Management"
         select PM_POWER_DOWN_TAGMEM_IN_LIGHT_SLEEP if ESP32S3_DATA_CACHE_16KB
         default y
         help
-            If enabled, the CPU will be powered down in light sleep. On esp32c3 soc, enabling this
-            option will consume 1.68 KB of internal RAM and will reduce sleep current consumption
-            by about 100 uA. On esp32s3 soc, enabling this option will consume 8.58 KB of internal
-            RAM and will reduce sleep current consumption by about 650 uA.
+            If enabled, the CPU will be powered down in light sleep, ESP chips supports saving and restoring CPU's
+            running context before and after light sleep, the feature provides applications with seamless CPU
+            powerdowned lightsleep without user awareness.
+            But this will takes up some internal memory. On esp32c3 soc, enabling this option will consume 1.68 KB
+            of internal RAM and will reduce sleep current consumption by about 100 uA. On esp32s3 soc, enabling this
+            option will consume 8.58 KB of internal RAM and will reduce sleep current consumption by about 650 uA.
 
     config PM_POWER_DOWN_TAGMEM_IN_LIGHT_SLEEP
-        bool "Power down I/D-cache tag memory in light sleep"
+        bool "Restore I/D-cache tag memory after power down CPU light sleep"
         depends on IDF_TARGET_ESP32S3 && PM_POWER_DOWN_CPU_IN_LIGHT_SLEEP
         default y
         help
-            If enabled, the I/D-cache tag memory will be retained in light sleep. Depending on the the
-            cache configuration, if this option is enabled, it will consume up to 9 KB of internal RAM.
+            Cache tag memory and CPU both belong to the CPU power domain. ESP chips supports saving and restoring Cache
+            tag memory before and after sleep, this feature supports accesses to the external memory that was cached
+            before sleep still be cached when the CPU wakes up from a powerdowned CPU lightsleep. This option controls
+            the restore method for Cache tag memory in lightsleep.
+            If this option is enabled, the I/D-cache tag memory will be backuped to the internal RAM before sleep and
+            restored upon wakeup. Depending on the the cache configuration, if this option is enabled, it will consume
+            up to 9 KB of internal RAM.
+            If this option is disabled, all cached data won't be kept after sleep, the DCache will be writeback before
+            sleep and invalid all cached data after sleep, all accesses to external memory(Flash/PSRAM) will be cache
+            missed after waking up, resulting in performance degradation due to increased memory accesses latency.
 
     config PM_UPDATE_CCOMPARE_HLI_WORKAROUND
         bool

components/esp_pm/pm_impl.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2016-2021 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2016-2023 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -292,21 +292,9 @@ esp_err_t esp_pm_configure(const void* vconfig)
                   min_freq_mhz,
                   config->light_sleep_enable ? "ENABLED" : "DISABLED");
 
-    portENTER_CRITICAL(&s_switch_lock);
-
-    bool res __attribute__((unused));
-    res = rtc_clk_cpu_freq_mhz_to_config(max_freq_mhz, &s_cpu_freq_by_mode[PM_MODE_CPU_MAX]);
-    assert(res);
-    res = rtc_clk_cpu_freq_mhz_to_config(apb_max_freq, &s_cpu_freq_by_mode[PM_MODE_APB_MAX]);
-    assert(res);
-    res = rtc_clk_cpu_freq_mhz_to_config(min_freq_mhz, &s_cpu_freq_by_mode[PM_MODE_APB_MIN]);
-    assert(res);
-    s_cpu_freq_by_mode[PM_MODE_LIGHT_SLEEP] = s_cpu_freq_by_mode[PM_MODE_APB_MIN];
-    s_light_sleep_en = config->light_sleep_enable;
-    s_config_changed = true;
-    portEXIT_CRITICAL(&s_switch_lock);
 
 #if CONFIG_PM_POWER_DOWN_CPU_IN_LIGHT_SLEEP && SOC_PM_SUPPORT_CPU_PD
+    // must be initialized before s_light_sleep_en set true, to avoid entering idle and sleep in this function.
     esp_err_t ret = esp_sleep_cpu_pd_low_init(config->light_sleep_enable);
     if (config->light_sleep_enable && ret != ESP_OK) {
         ESP_LOGW(TAG, "Failed to enable CPU power down during light sleep.");
@@ -319,6 +307,19 @@ esp_err_t esp_pm_configure(const void* vconfig)
     }
 #endif
 
+    portENTER_CRITICAL(&s_switch_lock);
+    bool res __attribute__((unused));
+    res = rtc_clk_cpu_freq_mhz_to_config(max_freq_mhz, &s_cpu_freq_by_mode[PM_MODE_CPU_MAX]);
+    assert(res);
+    res = rtc_clk_cpu_freq_mhz_to_config(apb_max_freq, &s_cpu_freq_by_mode[PM_MODE_APB_MAX]);
+    assert(res);
+    res = rtc_clk_cpu_freq_mhz_to_config(min_freq_mhz, &s_cpu_freq_by_mode[PM_MODE_APB_MIN]);
+    assert(res);
+    s_cpu_freq_by_mode[PM_MODE_LIGHT_SLEEP] = s_cpu_freq_by_mode[PM_MODE_APB_MIN];
+    s_light_sleep_en = config->light_sleep_enable;
+    s_config_changed = true;
+    portEXIT_CRITICAL(&s_switch_lock);
+
     return ESP_OK;
 }
 

components/hal/esp32s3/rtc_cntl_hal.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2019-2021 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2019-2023 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -68,6 +68,14 @@ void rtc_cntl_hal_enable_cpu_retention(void *addr)
                 );
             rtc_cntl_ll_enable_cpu_retention_clock();
             rtc_cntl_ll_enable_cpu_retention();
+#if SOC_PM_SUPPORT_TAGMEM_PD
+            if (!retent->tagmem.dcache.enable) {
+                // Here we only need to care for the safety of the PSRAM data in the DCache.
+                // Since only rodata, bss, heap data may be placed in PSRAM, and these data won't be
+                // modified in the sleep process code after now, so it is safe to writeback here.
+                Cache_WriteBack_All();
+            }
+#endif
         }
     }
 }