diff options
Diffstat (limited to 'roms/u-boot/drivers/crypto/fsl/rng.c')
-rw-r--r-- | roms/u-boot/drivers/crypto/fsl/rng.c | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/crypto/fsl/rng.c b/roms/u-boot/drivers/crypto/fsl/rng.c new file mode 100644 index 000000000..063649480 --- /dev/null +++ b/roms/u-boot/drivers/crypto/fsl/rng.c @@ -0,0 +1,88 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2020 Michael Walle <michael@walle.cc> + * + * Driver for Freescale Cryptographic Accelerator and Assurance + * Module (CAAM) hardware random number generator. + */ + +#include <asm/cache.h> +#include <common.h> +#include <cpu_func.h> +#include <dm.h> +#include <rng.h> +#include <linux/kernel.h> +#include "desc_constr.h" +#include "jobdesc.h" +#include "jr.h" + +#define CAAM_RNG_MAX_FIFO_STORE_SIZE 16 +#define CAAM_RNG_DESC_LEN (3 * CAAM_CMD_SZ + CAAM_PTR_SZ) + +struct caam_rng_priv { + u32 desc[CAAM_RNG_DESC_LEN / 4]; + u8 data[CAAM_RNG_MAX_FIFO_STORE_SIZE] __aligned(ARCH_DMA_MINALIGN); +}; + +static int caam_rng_read_one(struct caam_rng_priv *priv) +{ + int size = ALIGN(CAAM_RNG_MAX_FIFO_STORE_SIZE, ARCH_DMA_MINALIGN); + int ret; + + ret = run_descriptor_jr(priv->desc); + if (ret < 0) + return -EIO; + + invalidate_dcache_range((unsigned long)priv->data, + (unsigned long)priv->data + size); + + return 0; +} + +static int caam_rng_read(struct udevice *dev, void *data, size_t len) +{ + struct caam_rng_priv *priv = dev_get_priv(dev); + u8 *buffer = data; + size_t size; + int ret; + + while (len) { + ret = caam_rng_read_one(priv); + if (ret) + return ret; + + size = min(len, (size_t)CAAM_RNG_MAX_FIFO_STORE_SIZE); + + memcpy(buffer, priv->data, size); + buffer += size; + len -= size; + } + + return 0; +} + +static int caam_rng_probe(struct udevice *dev) +{ + struct caam_rng_priv *priv = dev_get_priv(dev); + ulong size = ALIGN(CAAM_RNG_DESC_LEN, ARCH_DMA_MINALIGN); + + inline_cnstr_jobdesc_rng(priv->desc, priv->data, + CAAM_RNG_MAX_FIFO_STORE_SIZE); + flush_dcache_range((unsigned long)priv->desc, + (unsigned long)priv->desc + size); + + return 0; +} + +static const struct dm_rng_ops caam_rng_ops = { + .read = caam_rng_read, +}; + +U_BOOT_DRIVER(caam_rng) = { + .name = "caam-rng", + .id = UCLASS_RNG, + .ops = &caam_rng_ops, + .probe = caam_rng_probe, + .priv_auto = sizeof(struct caam_rng_priv), + .flags = DM_FLAG_ALLOC_PRIV_DMA, +}; |