feat(spi_flash): Adds esp_flash_set_dangerous_write_protection

Author: KonstantinKondrashov

components/spi_flash/include/esp_flash_internal.h

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2015-2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2015-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -95,7 +95,27 @@ esp_err_t esp_flash_app_enable_os_functions(esp_flash_t* chip);
  */
 esp_err_t esp_flash_app_disable_os_functions(esp_flash_t* chip);
 
-
+/**
+ * @brief Set or clear dangerous write protection check on the flash chip.
+ *
+ * This function sets the runtime option to allow or disallow writing to
+ * dangerous areas such as the bootloader and partition table. If
+ * CONFIG_SPI_FLASH_DANGEROUS_WRITE_ALLOWED is not set, this function allows
+ * the caller to toggle the protection for specific areas.
+ *
+ * If CONFIG_SPI_FLASH_DANGEROUS_WRITE_ALLOWED is set, there is no protection
+ * check in the system, and this function does nothing.
+ *
+ * @param chip The flash chip on which to set the write protection. Only
+ *             "esp_flash_default_chip" is supported.
+ * @param protect Set to true to enable protection against writing in dangerous
+ *                areas (bootloader, partition table). Set to false to disable
+ *                the protection.
+ * @return
+ *         - ESP_OK: Successful operation.
+ *         - ESP_ERR_INVALID_ARG: The chip argument is null.
+ */
+esp_err_t esp_flash_set_dangerous_write_protection(esp_flash_t *chip, const bool protect);
 
 #ifdef __cplusplus
 }

components/spi_flash/spi_flash_os_func_app.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2015-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2015-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -350,6 +350,22 @@ esp_err_t esp_flash_app_enable_os_functions(esp_flash_t* chip)
     return ESP_OK;
 }
 
+esp_err_t esp_flash_set_dangerous_write_protection(esp_flash_t *chip, const bool protect)
+{
+#if !CONFIG_SPI_FLASH_DANGEROUS_WRITE_ALLOWED
+    if (chip == NULL) {
+        return ESP_ERR_INVALID_ARG;
+    }
+    if (chip->os_func_data != NULL) {
+        ((app_func_arg_t*)chip->os_func_data)->no_protect = !protect;
+    }
+#else
+    (void)chip;
+    (void)protect;
+#endif
+    return ESP_OK;
+}
+
 // The goal of this part is to manually insert one valid task execution interval, if the time since
 // last valid interval exceed the limitation (CONFIG_SPI_FLASH_ERASE_YIELD_DURATION_MS).
 //