1
0
mirror of https://github.com/trezor/trezor-firmware.git synced 2024-11-05 06:59:01 +00:00
trezor-firmware/legacy/rng.c
2019-06-17 20:28:29 +02:00

38 lines
1.2 KiB
C

/*
* This file is part of the Trezor project, https://trezor.io/
*
* Copyright (C) 2014 Pavol Rusnak <stick@satoshilabs.com>
*
* This library is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
#include <libopencm3/cm3/common.h>
#include <libopencm3/stm32/f2/rng.h>
#include <libopencm3/stm32/memorymap.h>
#include "rng.h"
#if !EMULATOR
uint32_t random32(void) {
static uint32_t last = 0, new = 0;
while (new == last) {
if ((RNG_SR & (RNG_SR_SECS | RNG_SR_CECS | RNG_SR_DRDY)) == RNG_SR_DRDY) {
new = RNG_DR;
}
}
last = new;
return new;
}
#endif