diff --git a/drivers/crypto/hisilicon/trng/trng.c b/drivers/crypto/hisilicon/trng/trng.c index ac74df4a9471..5ca0b90859a8 100644 --- a/drivers/crypto/hisilicon/trng/trng.c +++ b/drivers/crypto/hisilicon/trng/trng.c @@ -40,6 +40,7 @@ #define SEED_SHIFT_24 24 #define SEED_SHIFT_16 16 #define SEED_SHIFT_8 8 +#define SW_MAX_RANDOM_BYTES 65520 struct hisi_trng_list { struct mutex lock; @@ -53,8 +54,10 @@ struct hisi_trng { struct list_head list; struct hwrng rng; u32 ver; - bool is_used; - struct mutex mutex; + u32 ctx_num; + /* The bytes of the random number generated since the last seeding. */ + u32 random_bytes; + struct mutex lock; }; struct hisi_trng_ctx { @@ -63,10 +66,14 @@ struct hisi_trng_ctx { static atomic_t trng_active_devs; static struct hisi_trng_list trng_devices; +static int hisi_trng_read(struct hwrng *rng, void *buf, size_t max, bool wait); -static void hisi_trng_set_seed(struct hisi_trng *trng, const u8 *seed) +static int hisi_trng_set_seed(struct hisi_trng *trng, const u8 *seed) { u32 val, seed_reg, i; + int ret; + + writel(0x0, trng->base + SW_DRBG_BLOCKS); for (i = 0; i < SW_DRBG_SEED_SIZE; i += SW_DRBG_SEED_SIZE / SW_DRBG_SEED_REGS_NUM) { @@ -78,6 +85,20 @@ static void hisi_trng_set_seed(struct hisi_trng *trng, const u8 *seed) seed_reg = (i >> SW_DRBG_NUM_SHIFT) % SW_DRBG_SEED_REGS_NUM; writel(val, trng->base + SW_DRBG_SEED(seed_reg)); } + + writel(SW_DRBG_BLOCKS_NUM | (0x1 << SW_DRBG_ENABLE_SHIFT), + trng->base + SW_DRBG_BLOCKS); + writel(0x1, trng->base + SW_DRBG_INIT); + ret = readl_relaxed_poll_timeout(trng->base + SW_DRBG_STATUS, + val, val & BIT(0), SLEEP_US, TIMEOUT_US); + if (ret) { + pr_err("failed to init trng(%d)\n", ret); + return -EIO; + } + + trng->random_bytes = 0; + + return 0; } static int hisi_trng_seed(struct crypto_rng *tfm, const u8 *seed, @@ -85,8 +106,7 @@ static int hisi_trng_seed(struct crypto_rng *tfm, const u8 *seed, { struct hisi_trng_ctx *ctx = crypto_rng_ctx(tfm); struct hisi_trng *trng = ctx->trng; - u32 val = 0; - int ret = 0; + int ret; if (slen < SW_DRBG_SEED_SIZE) { pr_err("slen(%u) is not matched with trng(%d)\n", slen, @@ -94,43 +114,45 @@ static int hisi_trng_seed(struct crypto_rng *tfm, const u8 *seed, return -EINVAL; } - writel(0x0, trng->base + SW_DRBG_BLOCKS); - hisi_trng_set_seed(trng, seed); - - writel(SW_DRBG_BLOCKS_NUM | (0x1 << SW_DRBG_ENABLE_SHIFT), - trng->base + SW_DRBG_BLOCKS); - writel(0x1, trng->base + SW_DRBG_INIT); - - ret = readl_relaxed_poll_timeout(trng->base + SW_DRBG_STATUS, - val, val & BIT(0), SLEEP_US, TIMEOUT_US); - if (ret) - pr_err("fail to init trng(%d)\n", ret); + mutex_lock(&trng->lock); + ret = hisi_trng_set_seed(trng, seed); + mutex_unlock(&trng->lock); return ret; } -static int hisi_trng_generate(struct crypto_rng *tfm, const u8 *src, - unsigned int slen, u8 *dstn, unsigned int dlen) +static int hisi_trng_reseed(struct hisi_trng *trng) +{ + u8 seed[SW_DRBG_SEED_SIZE]; + int size; + + if (!trng->random_bytes) + return 0; + + size = hisi_trng_read(&trng->rng, seed, SW_DRBG_SEED_SIZE, false); + if (size != SW_DRBG_SEED_SIZE) + return -EIO; + + return hisi_trng_set_seed(trng, seed); +} + +static int hisi_trng_get_bytes(struct hisi_trng *trng, u8 *dstn, unsigned int dlen) { - struct hisi_trng_ctx *ctx = crypto_rng_ctx(tfm); - struct hisi_trng *trng = ctx->trng; u32 data[SW_DRBG_DATA_NUM]; u32 currsize = 0; u32 val = 0; int ret; u32 i; - if (dlen > SW_DRBG_BLOCKS_NUM * SW_DRBG_BYTES || dlen == 0) { - pr_err("dlen(%u) exceeds limit(%d)!\n", dlen, - SW_DRBG_BLOCKS_NUM * SW_DRBG_BYTES); - return -EINVAL; - } + ret = hisi_trng_reseed(trng); + if (ret) + return ret; do { ret = readl_relaxed_poll_timeout(trng->base + SW_DRBG_STATUS, - val, val & BIT(1), SLEEP_US, TIMEOUT_US); + val, val & BIT(1), SLEEP_US, TIMEOUT_US); if (ret) { - pr_err("fail to generate random number(%d)!\n", ret); + pr_err("failed to generate random number(%d)!\n", ret); break; } @@ -145,30 +167,57 @@ static int hisi_trng_generate(struct crypto_rng *tfm, const u8 *src, currsize = dlen; } + trng->random_bytes += SW_DRBG_BYTES; writel(0x1, trng->base + SW_DRBG_GEN); } while (currsize < dlen); return ret; } +static int hisi_trng_generate(struct crypto_rng *tfm, const u8 *src, + unsigned int slen, u8 *dstn, unsigned int dlen) +{ + struct hisi_trng_ctx *ctx = crypto_rng_ctx(tfm); + struct hisi_trng *trng = ctx->trng; + unsigned int currsize = 0; + unsigned int block_size; + int ret; + + if (!dstn || !dlen) { + pr_err("output is error, dlen %u!\n", dlen); + return -EINVAL; + } + + do { + block_size = min_t(unsigned int, dlen - currsize, SW_MAX_RANDOM_BYTES); + mutex_lock(&trng->lock); + ret = hisi_trng_get_bytes(trng, dstn + currsize, block_size); + mutex_unlock(&trng->lock); + if (ret) + return ret; + currsize += block_size; + } while (currsize < dlen); + + return 0; +} + static int hisi_trng_init(struct crypto_tfm *tfm) { struct hisi_trng_ctx *ctx = crypto_tfm_ctx(tfm); struct hisi_trng *trng; - int ret = -EBUSY; + u32 ctx_num = ~0; mutex_lock(&trng_devices.lock); list_for_each_entry(trng, &trng_devices.list, list) { - if (!trng->is_used) { - trng->is_used = true; + if (trng->ctx_num < ctx_num) { + ctx_num = trng->ctx_num; ctx->trng = trng; - ret = 0; - break; } } + ctx->trng->ctx_num++; mutex_unlock(&trng_devices.lock); - return ret; + return 0; } static void hisi_trng_exit(struct crypto_tfm *tfm) @@ -176,7 +225,7 @@ static void hisi_trng_exit(struct crypto_tfm *tfm) struct hisi_trng_ctx *ctx = crypto_tfm_ctx(tfm); mutex_lock(&trng_devices.lock); - ctx->trng->is_used = false; + ctx->trng->ctx_num--; mutex_unlock(&trng_devices.lock); } @@ -238,7 +287,7 @@ static int hisi_trng_del_from_list(struct hisi_trng *trng) int ret = -EBUSY; mutex_lock(&trng_devices.lock); - if (!trng->is_used) { + if (!trng->ctx_num) { list_del(&trng->list); ret = 0; } @@ -262,7 +311,9 @@ static int hisi_trng_probe(struct platform_device *pdev) if (IS_ERR(trng->base)) return PTR_ERR(trng->base); - trng->is_used = false; + trng->ctx_num = 0; + trng->random_bytes = SW_MAX_RANDOM_BYTES; + mutex_init(&trng->lock); trng->ver = readl(trng->base + HISI_TRNG_VERSION); if (!trng_devices.is_init) { INIT_LIST_HEAD(&trng_devices.list);