crypto: caam - add Derived Key Protocol (DKP) support

Offload split key generation in CAAM engine, using DKP.
DKP is supported starting with Era 6.

Note that the way assoclen is transmitted from the job descriptor
to the shared descriptor changes - DPOVRD register is used instead
of MATH3 (where available), since DKP protocol thrashes the MATH
registers.

The replacement of MDHA split key generation with DKP has the side
effect of the crypto engine writing the authentication key, and thus
the DMA mapping direction for the buffer holding the key has to change
from DMA_TO_DEVICE to DMA_BIDIRECTIONAL.
There are two cases:
-key is inlined in descriptor - descriptor buffer mapping changes
-key is referenced - key buffer mapping changes

Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 50 insertions, 23 deletions

diff --git a/drivers/crypto/caam/caamhash.c b/drivers/crypto/caam/caamhash.c
index 616720a04e7a..0beb28196e20 100644
--- a/drivers/crypto/caam/caamhash.c
+++ b/drivers/crypto/caam/caamhash.c
@@ -107,6 +107,7 @@ struct caam_hash_ctx {
 	dma_addr_t sh_desc_update_first_dma;
 	dma_addr_t sh_desc_fin_dma;
 	dma_addr_t sh_desc_digest_dma;
+	enum dma_data_direction dir;
 	struct device *jrdev;
 	u8 key[CAAM_MAX_HASH_KEY_SIZE];
 	int ctx_len;
@@ -241,7 +242,8 @@ static inline int ctx_map_to_sec4_sg(struct device *jrdev,
  *     read and write to seqout
  */
 static inline void ahash_gen_sh_desc(u32 *desc, u32 state, int digestsize,
-				     struct caam_hash_ctx *ctx, bool import_ctx)
+				     struct caam_hash_ctx *ctx, bool import_ctx,
+				     int era)
 {
 	u32 op = ctx->adata.algtype;
 	u32 *skip_key_load;
@@ -254,9 +256,12 @@ static inline void ahash_gen_sh_desc(u32 *desc, u32 state, int digestsize,
 		skip_key_load = append_jump(desc, JUMP_JSL | JUMP_TEST_ALL |
 					    JUMP_COND_SHRD);
 
-		append_key_as_imm(desc, ctx->key, ctx->adata.keylen_pad,
-				  ctx->adata.keylen, CLASS_2 |
-				  KEY_DEST_MDHA_SPLIT | KEY_ENC);
+		if (era < 6)
+			append_key_as_imm(desc, ctx->key, ctx->adata.keylen_pad,
+					  ctx->adata.keylen, CLASS_2 |
+					  KEY_DEST_MDHA_SPLIT | KEY_ENC);
+		else
+			append_proto_dkp(desc, &ctx->adata);
 
 		set_jump_tgt_here(desc, skip_key_load);
 
@@ -289,13 +294,17 @@ static int ahash_set_sh_desc(struct crypto_ahash *ahash)
 	struct caam_hash_ctx *ctx = crypto_ahash_ctx(ahash);
 	int digestsize = crypto_ahash_digestsize(ahash);
 	struct device *jrdev = ctx->jrdev;
+	struct caam_drv_private *ctrlpriv = dev_get_drvdata(jrdev->parent);
 	u32 *desc;
 
+	ctx->adata.key_virt = ctx->key;
+
 	/* ahash_update shared descriptor */
 	desc = ctx->sh_desc_update;
-	ahash_gen_sh_desc(desc, OP_ALG_AS_UPDATE, ctx->ctx_len, ctx, true);
+	ahash_gen_sh_desc(desc, OP_ALG_AS_UPDATE, ctx->ctx_len, ctx, true,
+			  ctrlpriv->era);
 	dma_sync_single_for_device(jrdev, ctx->sh_desc_update_dma,
-				   desc_bytes(desc), DMA_TO_DEVICE);
+				   desc_bytes(desc), ctx->dir);
 #ifdef DEBUG
 	print_hex_dump(KERN_ERR,
 		       "ahash update shdesc@"__stringify(__LINE__)": ",
@@ -304,9 +313,10 @@ static int ahash_set_sh_desc(struct crypto_ahash *ahash)
 
 	/* ahash_update_first shared descriptor */
 	desc = ctx->sh_desc_update_first;
-	ahash_gen_sh_desc(desc, OP_ALG_AS_INIT, ctx->ctx_len, ctx, false);
+	ahash_gen_sh_desc(desc, OP_ALG_AS_INIT, ctx->ctx_len, ctx, false,
+			  ctrlpriv->era);
 	dma_sync_single_for_device(jrdev, ctx->sh_desc_update_first_dma,
-				   desc_bytes(desc), DMA_TO_DEVICE);
+				   desc_bytes(desc), ctx->dir);
 #ifdef DEBUG
 	print_hex_dump(KERN_ERR,
 		       "ahash update first shdesc@"__stringify(__LINE__)": ",
@@ -315,9 +325,10 @@ static int ahash_set_sh_desc(struct crypto_ahash *ahash)
 
 	/* ahash_final shared descriptor */
 	desc = ctx->sh_desc_fin;
-	ahash_gen_sh_desc(desc, OP_ALG_AS_FINALIZE, digestsize, ctx, true);
+	ahash_gen_sh_desc(desc, OP_ALG_AS_FINALIZE, digestsize, ctx, true,
+			  ctrlpriv->era);
 	dma_sync_single_for_device(jrdev, ctx->sh_desc_fin_dma,
-				   desc_bytes(desc), DMA_TO_DEVICE);
+				   desc_bytes(desc), ctx->dir);
 #ifdef DEBUG
 	print_hex_dump(KERN_ERR, "ahash final shdesc@"__stringify(__LINE__)": ",
 		       DUMP_PREFIX_ADDRESS, 16, 4, desc,
@@ -326,9 +337,10 @@ static int ahash_set_sh_desc(struct crypto_ahash *ahash)
 
 	/* ahash_digest shared descriptor */
 	desc = ctx->sh_desc_digest;
-	ahash_gen_sh_desc(desc, OP_ALG_AS_INITFINAL, digestsize, ctx, false);
+	ahash_gen_sh_desc(desc, OP_ALG_AS_INITFINAL, digestsize, ctx, false,
+			  ctrlpriv->era);
 	dma_sync_single_for_device(jrdev, ctx->sh_desc_digest_dma,
-				   desc_bytes(desc), DMA_TO_DEVICE);
+				   desc_bytes(desc), ctx->dir);
 #ifdef DEBUG
 	print_hex_dump(KERN_ERR,
 		       "ahash digest shdesc@"__stringify(__LINE__)": ",
@@ -421,6 +433,7 @@ static int ahash_setkey(struct crypto_ahash *ahash,
 	struct caam_hash_ctx *ctx = crypto_ahash_ctx(ahash);
 	int blocksize = crypto_tfm_alg_blocksize(&ahash->base);
 	int digestsize = crypto_ahash_digestsize(ahash);
+	struct caam_drv_private *ctrlpriv = dev_get_drvdata(ctx->jrdev->parent);
 	int ret;
 	u8 *hashed_key = NULL;
 
@@ -441,16 +454,26 @@ static int ahash_setkey(struct crypto_ahash *ahash,
 		key = hashed_key;
 	}
 
-	ret = gen_split_key(ctx->jrdev, ctx->key, &ctx->adata, key, keylen,
-			    CAAM_MAX_HASH_KEY_SIZE);
-	if (ret)
-		goto bad_free_key;
+	/*
+	 * If DKP is supported, use it in the shared descriptor to generate
+	 * the split key.
+	 */
+	if (ctrlpriv->era >= 6) {
+		ctx->adata.key_inline = true;
+		ctx->adata.keylen = keylen;
+		ctx->adata.keylen_pad = split_key_len(ctx->adata.algtype &
+						      OP_ALG_ALGSEL_MASK);
 
-#ifdef DEBUG
-	print_hex_dump(KERN_ERR, "ctx.key@"__stringify(__LINE__)": ",
-		       DUMP_PREFIX_ADDRESS, 16, 4, ctx->key,
-		       ctx->adata.keylen_pad, 1);
-#endif
+		if (ctx->adata.keylen_pad > CAAM_MAX_HASH_KEY_SIZE)
+			goto bad_free_key;
+
+		memcpy(ctx->key, key, keylen);
+	} else {
+		ret = gen_split_key(ctx->jrdev, ctx->key, &ctx->adata, key,
+				    keylen, CAAM_MAX_HASH_KEY_SIZE);
+		if (ret)
+			goto bad_free_key;
+	}
 
 	kfree(hashed_key);
 	return ahash_set_sh_desc(ahash);
@@ -1715,6 +1738,7 @@ static int caam_hash_cra_init(struct crypto_tfm *tfm)
 					 HASH_MSG_LEN + 64,
 					 HASH_MSG_LEN + SHA512_DIGEST_SIZE };
 	dma_addr_t dma_addr;
+	struct caam_drv_private *priv;
 
 	/*
 	 * Get a Job ring from Job Ring driver to ensure in-order
@@ -1726,10 +1750,13 @@ static int caam_hash_cra_init(struct crypto_tfm *tfm)
 		return PTR_ERR(ctx->jrdev);
 	}
 
+	priv = dev_get_drvdata(ctx->jrdev->parent);
+	ctx->dir = priv->era >= 6 ? DMA_BIDIRECTIONAL : DMA_TO_DEVICE;
+
 	dma_addr = dma_map_single_attrs(ctx->jrdev, ctx->sh_desc_update,
 					offsetof(struct caam_hash_ctx,
 						 sh_desc_update_dma),
-					DMA_TO_DEVICE, DMA_ATTR_SKIP_CPU_SYNC);
+					ctx->dir, DMA_ATTR_SKIP_CPU_SYNC);
 	if (dma_mapping_error(ctx->jrdev, dma_addr)) {
 		dev_err(ctx->jrdev, "unable to map shared descriptors\n");
 		caam_jr_free(ctx->jrdev);
@@ -1764,7 +1791,7 @@ static void caam_hash_cra_exit(struct crypto_tfm *tfm)
 	dma_unmap_single_attrs(ctx->jrdev, ctx->sh_desc_update_dma,
 			       offsetof(struct caam_hash_ctx,
 					sh_desc_update_dma),
-			       DMA_TO_DEVICE, DMA_ATTR_SKIP_CPU_SYNC);
+			       ctx->dir, DMA_ATTR_SKIP_CPU_SYNC);
 	caam_jr_free(ctx->jrdev);
 }