[PATCH v2 04/12] crypto: atmel-sha: redefine SHA_FLAGS_SHA* flags to match SHA_MR_ALGO_SHA*

From: Cyrille Pitchen
Date: Thu Dec 22 2016 - 11:38:09 EST


This patch modifies the SHA_FLAGS_SHA* flags: those algo flags are now
organized as values of a single bitfield instead of individual bits.
This allows to reduce the number of bits needed to encode all possible
values. Also the new values match the SHA_MR_ALGO_SHA* values hence
the algorithm bitfield of the SHA_MR register could simply be set with:

mr = (mr & ~SHA_FLAGS_ALGO_MASK) | (ctx->flags & SHA_FLAGS_ALGO_MASK)

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxx>
---
drivers/crypto/atmel-sha-regs.h | 1 +
drivers/crypto/atmel-sha.c | 45 +++++++++++++++++++++++++++++------------
2 files changed, 33 insertions(+), 13 deletions(-)

diff --git a/drivers/crypto/atmel-sha-regs.h b/drivers/crypto/atmel-sha-regs.h
index e08897109cab..deb0b0b15096 100644
--- a/drivers/crypto/atmel-sha-regs.h
+++ b/drivers/crypto/atmel-sha-regs.h
@@ -19,6 +19,7 @@
#define SHA_MR_PROCDLY (1 << 4)
#define SHA_MR_UIHV (1 << 5)
#define SHA_MR_UIEHV (1 << 6)
+#define SHA_MR_ALGO_MASK GENMASK(10, 8)
#define SHA_MR_ALGO_SHA1 (0 << 8)
#define SHA_MR_ALGO_SHA256 (1 << 8)
#define SHA_MR_ALGO_SHA384 (2 << 8)
diff --git a/drivers/crypto/atmel-sha.c b/drivers/crypto/atmel-sha.c
index 643d79a05dda..b29a4e5bc404 100644
--- a/drivers/crypto/atmel-sha.c
+++ b/drivers/crypto/atmel-sha.c
@@ -51,14 +51,16 @@
#define SHA_FLAGS_CPU BIT(5)
#define SHA_FLAGS_DMA_READY BIT(6)

+/* bits[10:8] are reserved. */
+#define SHA_FLAGS_ALGO_MASK SHA_MR_ALGO_MASK
+#define SHA_FLAGS_SHA1 SHA_MR_ALGO_SHA1
+#define SHA_FLAGS_SHA256 SHA_MR_ALGO_SHA256
+#define SHA_FLAGS_SHA384 SHA_MR_ALGO_SHA384
+#define SHA_FLAGS_SHA512 SHA_MR_ALGO_SHA512
+#define SHA_FLAGS_SHA224 SHA_MR_ALGO_SHA224
+
#define SHA_FLAGS_FINUP BIT(16)
#define SHA_FLAGS_SG BIT(17)
-#define SHA_FLAGS_ALGO_MASK GENMASK(22, 18)
-#define SHA_FLAGS_SHA1 BIT(18)
-#define SHA_FLAGS_SHA224 BIT(19)
-#define SHA_FLAGS_SHA256 BIT(20)
-#define SHA_FLAGS_SHA384 BIT(21)
-#define SHA_FLAGS_SHA512 BIT(22)
#define SHA_FLAGS_ERROR BIT(23)
#define SHA_FLAGS_PAD BIT(24)
#define SHA_FLAGS_RESTORE BIT(25)
@@ -264,7 +266,9 @@ static void atmel_sha_fill_padding(struct atmel_sha_reqctx *ctx, int length)
bits[1] = cpu_to_be64(size[0] << 3);
bits[0] = cpu_to_be64(size[1] << 3 | size[0] >> 61);

- if (ctx->flags & (SHA_FLAGS_SHA384 | SHA_FLAGS_SHA512)) {
+ switch (ctx->flags & SHA_FLAGS_ALGO_MASK) {
+ case SHA_FLAGS_SHA384:
+ case SHA_FLAGS_SHA512:
index = ctx->bufcnt & 0x7f;
padlen = (index < 112) ? (112 - index) : ((128+112) - index);
*(ctx->buffer + ctx->bufcnt) = 0x80;
@@ -272,7 +276,9 @@ static void atmel_sha_fill_padding(struct atmel_sha_reqctx *ctx, int length)
memcpy(ctx->buffer + ctx->bufcnt + padlen, bits, 16);
ctx->bufcnt += padlen + 16;
ctx->flags |= SHA_FLAGS_PAD;
- } else {
+ break;
+
+ default:
index = ctx->bufcnt & 0x3f;
padlen = (index < 56) ? (56 - index) : ((64+56) - index);
*(ctx->buffer + ctx->bufcnt) = 0x80;
@@ -280,6 +286,7 @@ static void atmel_sha_fill_padding(struct atmel_sha_reqctx *ctx, int length)
memcpy(ctx->buffer + ctx->bufcnt + padlen, &bits[1], 8);
ctx->bufcnt += padlen + 8;
ctx->flags |= SHA_FLAGS_PAD;
+ break;
}
}

@@ -828,16 +835,28 @@ static void atmel_sha_copy_ready_hash(struct ahash_request *req)
if (!req->result)
return;

- if (ctx->flags & SHA_FLAGS_SHA1)
+ switch (ctx->flags & SHA_FLAGS_ALGO_MASK) {
+ default:
+ case SHA_FLAGS_SHA1:
memcpy(req->result, ctx->digest, SHA1_DIGEST_SIZE);
- else if (ctx->flags & SHA_FLAGS_SHA224)
+ break;
+
+ case SHA_FLAGS_SHA224:
memcpy(req->result, ctx->digest, SHA224_DIGEST_SIZE);
- else if (ctx->flags & SHA_FLAGS_SHA256)
+ break;
+
+ case SHA_FLAGS_SHA256:
memcpy(req->result, ctx->digest, SHA256_DIGEST_SIZE);
- else if (ctx->flags & SHA_FLAGS_SHA384)
+ break;
+
+ case SHA_FLAGS_SHA384:
memcpy(req->result, ctx->digest, SHA384_DIGEST_SIZE);
- else
+ break;
+
+ case SHA_FLAGS_SHA512:
memcpy(req->result, ctx->digest, SHA512_DIGEST_SIZE);
+ break;
+ }
}

static int atmel_sha_finish(struct ahash_request *req)
--
2.7.4