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@@ -0,0 +1,56 @@
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+// 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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+
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+#include <common.h>
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+#include <dm.h>
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+#include <rng.h>
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+
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+#include <linux/string.h>
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+
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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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+
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+ if (!len)
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+ return 0;
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+
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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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+
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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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+
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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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+
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+ return 0;
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+}
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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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+
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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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+
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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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