crypto: sun8i-ce - Add support for the PRNG

This patch had support for the PRNG present in the CE.
The output was tested with rngtest without any failure.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 57 insertions, 1 deletions

diff --git a/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-core.c b/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-core.c
index a7fd27a1700e..3af5f9783607 100644
--- a/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-core.c
+++ b/drivers/crypto/allwinner/sun8i-ce/sun8i-ce-core.c
@@ -22,6 +22,7 @@
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/reset.h>
+#include <crypto/internal/rng.h>
 #include <crypto/internal/skcipher.h>
 
 #include "sun8i-ce.h"
@@ -45,6 +46,7 @@ static const struct ce_variant ce_h3_variant = {
 		{ "mod", 50000000, 0 },
 		},
 	.esr = ESR_H3,
+	.prng = CE_ALG_PRNG,
 };
 
 static const struct ce_variant ce_h5_variant = {
@@ -60,6 +62,7 @@ static const struct ce_variant ce_h5_variant = {
 		{ "mod", 300000000, 0 },
 		},
 	.esr = ESR_H5,
+	.prng = CE_ALG_PRNG,
 };
 
 static const struct ce_variant ce_h6_variant = {
@@ -72,12 +75,14 @@ static const struct ce_variant ce_h6_variant = {
 	},
 	.cipher_t_dlen_in_bytes = true,
 	.hash_t_dlen_in_bits = true,
+	.prng_t_dlen_in_bytes = true,
 	.ce_clks = {
 		{ "bus", 0, 200000000 },
 		{ "mod", 300000000, 0 },
 		{ "ram", 0, 400000000 },
 		},
 	.esr = ESR_H6,
+	.prng = CE_ALG_PRNG_V2,
 };
 
 static const struct ce_variant ce_a64_variant = {
@@ -93,6 +98,7 @@ static const struct ce_variant ce_a64_variant = {
 		{ "mod", 300000000, 0 },
 		},
 	.esr = ESR_A64,
+	.prng = CE_ALG_PRNG,
 };
 
 static const struct ce_variant ce_r40_variant = {
@@ -108,15 +114,17 @@ static const struct ce_variant ce_r40_variant = {
 		{ "mod", 300000000, 0 },
 		},
 	.esr = ESR_R40,
+	.prng = CE_ALG_PRNG,
 };
 
 /*
  * sun8i_ce_get_engine_number() get the next channel slot
  * This is a simple round-robin way of getting the next channel
+ * The flow 3 is reserve for xRNG operations
  */
 int sun8i_ce_get_engine_number(struct sun8i_ce_dev *ce)
 {
-	return atomic_inc_return(&ce->flow) % MAXFLOW;
+	return atomic_inc_return(&ce->flow) % (MAXFLOW - 1);
 }
 
 int sun8i_ce_run_task(struct sun8i_ce_dev *ce, int flow, const char *name)
@@ -527,6 +535,25 @@ static struct sun8i_ce_alg_template ce_algs[] = {
 	}
 },
 #endif
+#ifdef CONFIG_CRYPTO_DEV_SUN8I_CE_PRNG
+{
+	.type = CRYPTO_ALG_TYPE_RNG,
+	.alg.rng = {
+		.base = {
+			.cra_name		= "stdrng",
+			.cra_driver_name	= "sun8i-ce-prng",
+			.cra_priority		= 300,
+			.cra_ctxsize		= sizeof(struct sun8i_ce_rng_tfm_ctx),
+			.cra_module		= THIS_MODULE,
+			.cra_init		= sun8i_ce_prng_init,
+			.cra_exit		= sun8i_ce_prng_exit,
+		},
+		.generate               = sun8i_ce_prng_generate,
+		.seed                   = sun8i_ce_prng_seed,
+		.seedsize               = PRNG_SEED_SIZE,
+	}
+},
+#endif
 };
 
 #ifdef CONFIG_CRYPTO_DEV_SUN8I_CE_DEBUG
@@ -554,6 +581,12 @@ static int sun8i_ce_debugfs_show(struct seq_file *seq, void *v)
 				   ce_algs[i].alg.hash.halg.base.cra_name,
 				   ce_algs[i].stat_req, ce_algs[i].stat_fb);
 			break;
+		case CRYPTO_ALG_TYPE_RNG:
+			seq_printf(seq, "%s %s %lu %lu\n",
+				   ce_algs[i].alg.rng.base.cra_driver_name,
+				   ce_algs[i].alg.rng.base.cra_name,
+				   ce_algs[i].stat_req, ce_algs[i].stat_bytes);
+			break;
 		}
 	}
 	return 0;
@@ -777,6 +810,23 @@ static int sun8i_ce_register_algs(struct sun8i_ce_dev *ce)
 				return err;
 			}
 			break;
+		case CRYPTO_ALG_TYPE_RNG:
+			if (ce->variant->prng == CE_ID_NOTSUPP) {
+				dev_info(ce->dev,
+					 "DEBUG: Algo of %s not supported\n",
+					 ce_algs[i].alg.rng.base.cra_name);
+				ce_algs[i].ce = NULL;
+				break;
+			}
+			dev_info(ce->dev, "Register %s\n",
+				 ce_algs[i].alg.rng.base.cra_name);
+			err = crypto_register_rng(&ce_algs[i].alg.rng);
+			if (err) {
+				dev_err(ce->dev, "Fail to register %s\n",
+					ce_algs[i].alg.rng.base.cra_name);
+				ce_algs[i].ce = NULL;
+			}
+			break;
 		default:
 			ce_algs[i].ce = NULL;
 			dev_err(ce->dev, "ERROR: tried to register an unknown algo\n");
@@ -803,6 +853,11 @@ static void sun8i_ce_unregister_algs(struct sun8i_ce_dev *ce)
 				 ce_algs[i].alg.hash.halg.base.cra_name);
 			crypto_unregister_ahash(&ce_algs[i].alg.hash);
 			break;
+		case CRYPTO_ALG_TYPE_RNG:
+			dev_info(ce->dev, "Unregister %d %s\n", i,
+				 ce_algs[i].alg.rng.base.cra_name);
+			crypto_unregister_rng(&ce_algs[i].alg.rng);
+			break;
 		}
 	}
 }
@@ -845,6 +900,7 @@ static int sun8i_ce_probe(struct platform_device *pdev)
 				     "No reset control found\n");
 
 	mutex_init(&ce->mlock);
+	mutex_init(&ce->rnglock);
 
 	err = sun8i_ce_allocate_chanlist(ce);
 	if (err)