tillitis-key/hw/application_fpga/fw/tk1/rng.c
Daniel Jobson a37f687881 Change license to BSD-2-Clause
This was announced on the Tillitis Blog the 2nd of October 2024, for
more info visit https://tillitis.se
2025-10-30 13:07:59 +01:00

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634 B
C

// Copyright (C) 2024 - Tillitis AB
// SPDX-License-Identifier: BSD-2-Clause
#include "rng.h"
#include <tkey/tk1_mem.h>
#include <stdint.h>
// clang-format off
static volatile uint32_t *trng_status = (volatile uint32_t *)TK1_MMIO_TRNG_STATUS;
static volatile uint32_t *trng_entropy = (volatile uint32_t *)TK1_MMIO_TRNG_ENTROPY;
// clang-format on
uint32_t rng_get_word(void)
{
while ((*trng_status & (1 << TK1_MMIO_TRNG_STATUS_READY_BIT)) == 0) {
}
return *trng_entropy;
}
uint32_t rng_xorwow(uint32_t state, uint32_t acc)
{
state ^= state << 13;
state ^= state >> 17;
state ^= state << 5;
state += acc;
return state;
}