circuitpython/ports/nrf/drivers/rng.c

80 lines
2.4 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2017-2018 Glenn Ruben Bakke
* Copyright (c) 2018 Ayke van Laethem
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "py/mpconfig.h"
#if MICROPY_HW_ENABLE_RNG
#include "nrf_rng.h"
#include "drivers/rng.h"
#if BLUETOOTH_SD
#include "nrf_soc.h"
#include "ble_drv.h"
#define BLUETOOTH_STACK_ENABLED() (ble_drv_stack_enabled())
#endif
static inline uint32_t generate_hw_random(void) {
uint32_t retval = 0;
uint8_t * p_retval = (uint8_t *)&retval;
nrf_rng_event_clear(NRF_RNG, NRF_RNG_EVENT_VALRDY);
nrf_rng_task_trigger(NRF_RNG, NRF_RNG_TASK_START);
for (uint16_t i = 0; i < 4; i++) {
while (!nrf_rng_event_check(NRF_RNG, NRF_RNG_EVENT_VALRDY)) {
;
}
nrf_rng_event_clear(NRF_RNG, NRF_RNG_EVENT_VALRDY);
p_retval[i] = nrf_rng_random_value_get(NRF_RNG);
}
nrf_rng_task_trigger(NRF_RNG, NRF_RNG_TASK_STOP);
return retval;
}
uint32_t rng_generate_random_word(void) {
#if BLUETOOTH_SD
if (BLUETOOTH_STACK_ENABLED() == 1) {
uint32_t retval = 0;
uint32_t status;
do {
status = sd_rand_application_vector_get((uint8_t *)&retval, 4); // Extract 4 bytes
} while (status != 0);
return retval;
}
#endif
return generate_hw_random();
}
#endif // MICROPY_HW_ENABLE_RNG