esp-idf/components/esp_rom/include/esp_rom_efuse.h

// Copyright 2010-2020 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#pragma once

#ifdef __cplusplus
extern "C" {
#endif

#include <stdint.h>
#include <stdbool.h>

#define ESP_ROM_EFUSE_FLASH_DEFAULT_SPI  (0)
#define ESP_ROM_EFUSE_FLASH_DEFAULT_HSPI (1)

/**
 * @brief A CRC8 algorithm used for MAC addresses stored in eFuse
 *
 * @param data Pointer to the original data
 * @param len Data length in byte
 * @return uint8_t CRC value
 */
uint8_t esp_rom_efuse_mac_address_crc8(const uint8_t *data, uint32_t len);

/**
 * @brief Get SPI Flash GPIO pin configurations from eFuse
 *
 * @return uint32_t
 *          - 0: default SPI pins (ESP_ROM_EFUSE_FLASH_DEFAULT_SPI)
 *          - 1: default HSPI pins (ESP_ROM_EFUSE_FLASH_DEFAULT_HSPI)
 *          - Others: Customized pin configuration mask. Pins are encoded as per the
 *                    EFUSE_SPICONFIG_RET_SPICLK, EFUSE_SPICONFIG_RET_SPIQ, EFUSE_SPICONFIG_RET_SPID,
 *                    EFUSE_SPICONFIG_RET_SPICS0, EFUSE_SPICONFIG_RET_SPIHD macros.
 *
 * @note WP pin (for quad I/O modes) is not saved in eFuse and not returned by this function.
 */
uint32_t esp_rom_efuse_get_flash_gpio_info(void);

/**
 * @brief Get SPI Flash WP pin information from eFuse
 *
 * @return uint32_t
 *      - 0x3F: invalid GPIO number
 *      - 0~46: valid GPIO number
 */
uint32_t esp_rom_efuse_get_flash_wp_gpio(void);

/**
 * @brief Read eFuse to check whether secure boot has been enabled or not
 *
 * @return true if secure boot is enabled, otherwise false
 */
bool esp_rom_efuse_is_secure_boot_enabled(void);

#ifdef __cplusplus
}
#endif