58 lines
1014 B
C
58 lines
1014 B
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Copyright (c) 2019, Linaro Limited
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*/
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#include <common.h>
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#include <dm.h>
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#include <rand.h>
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#include <rng.h>
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#include <linux/string.h>
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static int sandbox_rng_read(struct udevice *dev, void *data, size_t len)
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{
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unsigned int i, seed, random;
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unsigned char *buf = data;
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size_t nrem, nloops;
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if (!len)
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return 0;
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nloops = len / sizeof(random);
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seed = get_timer(0) ^ rand();
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srand(seed);
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for (i = 0, nrem = len; i < nloops; i++) {
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random = rand();
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memcpy(buf, &random, sizeof(random));
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buf += sizeof(random);
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nrem -= sizeof(random);
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}
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if (nrem) {
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random = rand();
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memcpy(buf, &random, nrem);
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}
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return 0;
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}
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static const struct dm_rng_ops sandbox_rng_ops = {
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.read = sandbox_rng_read,
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};
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static const struct udevice_id sandbox_rng_match[] = {
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{
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.compatible = "sandbox,sandbox-rng",
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},
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{},
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};
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U_BOOT_DRIVER(sandbox_rng) = {
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.name = "sandbox-rng",
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.id = UCLASS_RNG,
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.of_match = sandbox_rng_match,
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.ops = &sandbox_rng_ops,
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};
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