linuxdebug/drivers/crypto/gemini/sl3516-ce-rng.c

62 lines
1.2 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* sl3516-ce-rng.c - hardware cryptographic offloader for SL3516 SoC.
*
* Copyright (C) 2021 Corentin Labbe <clabbe@baylibre.com>
*
* This file handle the RNG found in the SL3516 crypto engine
*/
#include "sl3516-ce.h"
#include <linux/pm_runtime.h>
#include <linux/hw_random.h>
static int sl3516_ce_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
{
struct sl3516_ce_dev *ce;
u32 *data = buf;
size_t read = 0;
int err;
ce = container_of(rng, struct sl3516_ce_dev, trng);
#ifdef CONFIG_CRYPTO_DEV_SL3516_DEBUG
ce->hwrng_stat_req++;
ce->hwrng_stat_bytes += max;
#endif
err = pm_runtime_get_sync(ce->dev);
if (err < 0) {
pm_runtime_put_noidle(ce->dev);
return err;
}
while (read < max) {
*data = readl(ce->base + IPSEC_RAND_NUM_REG);
data++;
read += 4;
}
pm_runtime_put(ce->dev);
return read;
}
int sl3516_ce_rng_register(struct sl3516_ce_dev *ce)
{
int ret;
ce->trng.name = "SL3516 Crypto Engine RNG";
ce->trng.read = sl3516_ce_rng_read;
ce->trng.quality = 700;
ret = hwrng_register(&ce->trng);
if (ret)
dev_err(ce->dev, "Fail to register the RNG\n");
return ret;
}
void sl3516_ce_rng_unregister(struct sl3516_ce_dev *ce)
{
hwrng_unregister(&ce->trng);
}