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.

Author: MattiasTF

components/esp_system/port/cpu_start.c

@@ -634,6 +634,22 @@ MSPI_INIT_ATTR void mspi_init(void)
     }
 #endif
 }
+
+#if CONFIG_IDF_TARGET_ESP32
+#if !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_SPIRAM_BOOT_HW_INIT
+#endif // CONFIG_IDF_TARGET_ESP32
 #endif // !CONFIG_APP_BUILD_TYPE_PURE_RAM_APP
 
 /*
@@ -874,10 +890,7 @@ 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