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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) 2019, Linaro Limited
*/
#include <dm.h>
#include <rand.h>
#include <rng.h>
#include <time.h>
#include <linux/string.h>
static int sandbox_rng_read(struct udevice *dev, void *data, size_t len)
{
unsigned int i, seed, random;
unsigned char *buf = data;
size_t nrem, nloops;
if (!len)
return 0;
nloops = len / sizeof(random);
seed = get_timer(0) ^ rand();
srand(seed);
for (i = 0, nrem = len; i < nloops; i++) {
random = rand();
memcpy(buf, &random, sizeof(random));
buf += sizeof(random);
nrem -= sizeof(random);
}
if (nrem) {
random = rand();
memcpy(buf, &random, nrem);
}
return 0;
}
static const struct dm_rng_ops sandbox_rng_ops = {
.read = sandbox_rng_read,
};
static const struct udevice_id sandbox_rng_match[] = {
{
.compatible = "sandbox,sandbox-rng",
},
{},
};
U_BOOT_DRIVER(sandbox_rng) = {
.name = "sandbox-rng",
.id = UCLASS_RNG,
.of_match = sandbox_rng_match,
.ops = &sandbox_rng_ops,
};
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