From 02a3b294a526e1a3bfbb12422941f7bd0ff9a08f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Mattias=20Sch=C3=A4ffersmann?= Date: Wed, 19 Nov 2025 19:16:53 +0100 Subject: [PATCH] fix(hw_support): Fix crash when reconfiguring flash from 40 to 80 MHz Reading from the flash while it is being reconfigured leads to data corruption and a crash when the reconfiguration code is located in flash. This is only an issue if a device has a bootloader that runs with 40 MHz flash and an application flashed via OTA that runs with 80 MHz flash. If bootloader and application run with the same flash speed, the reconfiguration is basically a no-op and no data corruption occurs. Fix reconfiguration by placing the code back into IRAM. Issue introduced in: 7549d08 Closes: https://github.com/espressif/esp-idf/pull/17905 --- components/esp_system/port/cpu_start.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff --git a/components/esp_system/port/cpu_start.c b/components/esp_system/port/cpu_start.c index cbd5dafa3c..a9b310c08a 100644 --- a/components/esp_system/port/cpu_start.c +++ b/components/esp_system/port/cpu_start.c @@ -612,6 +612,20 @@ MSPI_INIT_ATTR void mspi_init(void) } #endif // !CONFIG_APP_BUILD_TYPE_PURE_RAM_APP +#if CONFIG_IDF_TARGET_ESP32 && !CONFIG_APP_BUILD_TYPE_RAM && !CONFIG_SPIRAM_BOOT_HW_INIT +/* + * Adjust flash configuration. This must be placed in IRAM because running from flash, + * while it is being reconfigured, will result in corrupt data being read. + */ +NOINLINE_ATTR IRAM_ATTR static void configure_flash(esp_image_header_t *fhdr) +{ + bootloader_flash_gpio_config(fhdr); + bootloader_flash_dummy_config(fhdr); + bootloader_flash_clock_config(fhdr); + bootloader_flash_cs_timing_config(); +} +#endif // CONFIG_IDF_TARGET_ESP32 && !CONFIG_APP_BUILD_TYPE_RAM && !CONFIG_SPIRAM_BOOT_HW_INIT + /* * Initialize other parts of the system, including other CPUs. * As CPU0 needs to disable the cache in system_early_init function, the other cores are not allowed to run with the @@ -851,10 +865,7 @@ NOINLINE_ATTR static void system_early_init(const soc_reset_reason_t *rst_reas) #if CONFIG_IDF_TARGET_ESP32 #if !CONFIG_SPIRAM_BOOT_HW_INIT // If psram is uninitialized, we need to improve some flash configuration. - bootloader_flash_clock_config(&fhdr); - bootloader_flash_gpio_config(&fhdr); - bootloader_flash_dummy_config(&fhdr); - bootloader_flash_cs_timing_config(); + configure_flash(&fhdr); #endif //!CONFIG_SPIRAM_BOOT_HW_INIT #endif //CONFIG_IDF_TARGET_ESP32