espressif: Fix flash_area_write support for unaligned write accesses (1eb3ecae) · Commits · Wenxi XU / Mcuboot

boot/espressif/port/esp_mcuboot.c

+57 −3

Original line number	Diff line number	Diff line
		@@ -210,6 +210,61 @@ int flash_area_read(const struct flash_area fa, uint32_t off, void dst,
		return 0;
		}

		static bool aligned_flash_write(size_t dest_addr, const void *src, size_t size)
		{
		bool flash_encryption_enabled = esp_flash_encryption_enabled();

		if (IS_ALIGNED(dest_addr, 4) && IS_ALIGNED((uintptr_t)src, 4) && IS_ALIGNED(size, 4)) {
		/* A single write operation is enough when all parameters are aligned */

		return bootloader_flash_write(dest_addr, (void *)src, size, flash_encryption_enabled) == ESP_OK;
		}

		const uint32_t aligned_addr = ALIGN_DOWN(dest_addr, 4);
		const uint32_t addr_offset = ALIGN_OFFSET(dest_addr, 4);
		uint32_t bytes_remaining = size;
		uint8_t write_data[FLASH_BUFFER_SIZE] = {0};

		/* Perform a read operation considering an offset not aligned to 4-byte boundary */

		uint32_t bytes = MIN(bytes_remaining + addr_offset, sizeof(write_data));
		if (bootloader_flash_read(aligned_addr, write_data, ALIGN_UP(bytes, 4), true) != ESP_OK) {
		return false;
		}

		uint32_t bytes_written = bytes - addr_offset;
		memcpy(&write_data[addr_offset], src, bytes_written);

		if (bootloader_flash_write(aligned_addr, write_data, ALIGN_UP(bytes, 4), flash_encryption_enabled) != ESP_OK) {
		return false;
		}

		bytes_remaining -= bytes_written;

		/* Write remaining data to Flash if any */

		uint32_t offset = bytes;

		while (bytes_remaining != 0) {
		bytes = MIN(bytes_remaining, sizeof(write_data));
		if (bootloader_flash_read(aligned_addr + offset, write_data, ALIGN_UP(bytes, 4), true) != ESP_OK) {
		return false;
		}

		memcpy(write_data, &((uint8_t *)src)[bytes_written], bytes);

		if (bootloader_flash_write(aligned_addr + offset, write_data, ALIGN_UP(bytes, 4), flash_encryption_enabled) != ESP_OK) {
		return false;
		}

		offset += bytes;
		bytes_written += bytes;
		bytes_remaining -= bytes;
		}

		return true;
		}

		int flash_area_write(const struct flash_area fa, uint32_t off, const void src,
		uint32_t len)
		{
		@@ -223,12 +278,11 @@ int flash_area_write(const struct flash_area fa, uint32_t off, const void src,
		return -1;
		}

		bool flash_encryption_enabled = esp_flash_encryption_enabled();

		const uint32_t start_addr = fa->fa_off + off;
		BOOT_LOG_DBG("%s: Addr: 0x%08x Length: %d", __func__, (int)start_addr, (int)len);

		if (bootloader_flash_write(start_addr, (void *)src, len, flash_encryption_enabled) != ESP_OK) {
		bool success = aligned_flash_write(start_addr, src, len);
		if (!success) {
		BOOT_LOG_ERR("%s: Flash write failed", __func__);
		return -1;
		}

Admin message