Files
esp-idf/components/bootloader_support/include/bootloader_random.h
2021-05-10 04:58:34 +02:00

50 lines
1.1 KiB
C

/*
* SPDX-FileCopyrightText: 2010-2021 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#pragma once
#include <stddef.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief Enable early entropy source for RNG
*
* Uses the SAR ADC to feed entropy into the HWRNG. The ADC is put
* into a test mode that reads the 1.1V internal reference source and
* feeds the LSB of data into the HWRNG.
*
* Can also be used from app code early during operation, if entropy
* is required before WiFi stack is initialised. Call this function
* from app code only if WiFi/BT are not yet enabled and I2S and SAR
* ADC are not in use.
*
* Call bootloader_random_disable() when done.
*/
void bootloader_random_enable(void);
/**
* @brief Disable early entropy source for RNG
*
* Disables SAR ADC source and resets the I2S hardware.
*
*/
void bootloader_random_disable(void);
/**
* @brief Fill buffer with 'length' random bytes
*
* @param buffer Pointer to buffer
* @param length This many bytes of random data will be copied to buffer
*/
void bootloader_fill_random(void *buffer, size_t length);
#ifdef __cplusplus
}
#endif