el(0x1, trng->base + SW_DRBG_INIT);
+	return ret;
+}
 
-	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);
+static int hisi_trng_reseed(struct hisi_trng *trng)
+{
+	u8 seed[SW_DRBG_SEED_SIZE];
+	int size;
 
-	return ret;
+	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_generate(struct crypto_rng *tfm, const u8 *src,
-			      unsigned int slen, u8 *dstn, unsigned int dlen)
+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);
-- 
2.51.0[PATCH 6.19 114/781] crypto: hisilicon/trng - support tfms sharing the deviceGreg Kroah-Hartman <gregkh@linuxfoundation.org> undefinedstable@vger.kernel.org undefined undefined undefined undefined undefined undefined