crypto: talitos - do not perform unnecessary dma synchronisation

req_ctx->hw_context is mainly used only by the HW. So it is not needed
to sync the HW and the CPU each time hw_context in DMA mapped.
This patch modifies the DMA mapping in order to limit synchronisation
to necessary situations.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 63 insertions, 22 deletions

diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c
index bb44df1c1f2d..447cb8b1b16a 100644
--- a/drivers/crypto/talitos.c
+++ b/drivers/crypto/talitos.c
@@ -104,16 +104,34 @@ static void to_talitos_ptr_ext_or(struct talitos_ptr *ptr, u8 val, bool is_sec1)
 /*
  * map virtual single (contiguous) pointer to h/w descriptor pointer
  */
+static void __map_single_talitos_ptr(struct device *dev,
+                                     struct talitos_ptr *ptr,
+                                     unsigned int len, void *data,
+                                     enum dma_data_direction dir,
+                                     unsigned long attrs)
+{
+        dma_addr_t dma_addr = dma_map_single_attrs(dev, data, len, dir, attrs);
+        struct talitos_private *priv = dev_get_drvdata(dev);
+        bool is_sec1 = has_ftr_sec1(priv);
+
+        to_talitos_ptr(ptr, dma_addr, len, is_sec1);
+}
+
 static void map_single_talitos_ptr(struct device *dev,
                                    struct talitos_ptr *ptr,
                                    unsigned int len, void *data,
                                    enum dma_data_direction dir)
 {
-        dma_addr_t dma_addr = dma_map_single(dev, data, len, dir);
-        struct talitos_private *priv = dev_get_drvdata(dev);
-        bool is_sec1 = has_ftr_sec1(priv);
+        __map_single_talitos_ptr(dev, ptr, len, data, dir, 0);
+}
 
-        to_talitos_ptr(ptr, dma_addr, len, is_sec1);
+static void map_single_talitos_ptr_nosync(struct device *dev,
+                                          struct talitos_ptr *ptr,
+                                          unsigned int len, void *data,
+                                          enum dma_data_direction dir)
+{
+        __map_single_talitos_ptr(dev, ptr, len, data, dir,
+                                 DMA_ATTR_SKIP_CPU_SYNC);
 }
 
 /*
@@ -1785,10 +1803,10 @@ static int common_nonsnoop_hash(struct talitos_edesc *edesc,
 
         /* hash context in */
         if (!req_ctx->first || req_ctx->swinit) {
-                map_single_talitos_ptr(dev, &desc->ptr[1],
-                                       req_ctx->hw_context_size,
-                                       (char *)req_ctx->hw_context,
-                                       DMA_TO_DEVICE);
+                map_single_talitos_ptr_nosync(dev, &desc->ptr[1],
+                                              req_ctx->hw_context_size,
+                                              req_ctx->hw_context,
+                                              DMA_TO_DEVICE);
                 req_ctx->swinit = 0;
         }
         /* Indicate next op is not the first. */
@@ -1832,9 +1850,10 @@ static int common_nonsnoop_hash(struct talitos_edesc *edesc,
                                        crypto_ahash_digestsize(tfm),
                                        areq->result, DMA_FROM_DEVICE);
         else
-                map_single_talitos_ptr(dev, &desc->ptr[5],
-                                       req_ctx->hw_context_size,
-                                       req_ctx->hw_context, DMA_FROM_DEVICE);
+                map_single_talitos_ptr_nosync(dev, &desc->ptr[5],
+                                              req_ctx->hw_context_size,
+                                              req_ctx->hw_context,
+                                              DMA_FROM_DEVICE);
 
         /* last DWORD empty */
 
@@ -1857,10 +1876,10 @@ static int common_nonsnoop_hash(struct talitos_edesc *edesc,
                         copy_talitos_ptr(&desc2->ptr[1], &desc->ptr[1],
                                          is_sec1);
                 else
-                        map_single_talitos_ptr(dev, &desc2->ptr[1],
-                                               req_ctx->hw_context_size,
-                                               req_ctx->hw_context,
-                                               DMA_TO_DEVICE);
+                        map_single_talitos_ptr_nosync(dev, &desc2->ptr[1],
+                                                      req_ctx->hw_context_size,
+                                                      req_ctx->hw_context,
+                                                      DMA_TO_DEVICE);
                 copy_talitos_ptr(&desc2->ptr[2], &desc->ptr[2], is_sec1);
                 sg_count = talitos_sg_map(dev, req_ctx->psrc, length, edesc,
                                           &desc2->ptr[3], sg_count, offset, 0);
@@ -1868,10 +1887,10 @@ static int common_nonsnoop_hash(struct talitos_edesc *edesc,
                         sync_needed = true;
                 copy_talitos_ptr(&desc2->ptr[5], &desc->ptr[5], is_sec1);
                 if (req_ctx->last)
-                        map_single_talitos_ptr(dev, &desc->ptr[5],
-                                               req_ctx->hw_context_size,
-                                               req_ctx->hw_context,
-                                               DMA_FROM_DEVICE);
+                        map_single_talitos_ptr_nosync(dev, &desc->ptr[5],
+                                                      req_ctx->hw_context_size,
+                                                      req_ctx->hw_context,
+                                                      DMA_FROM_DEVICE);
 
                 next_desc = dma_map_single(dev, &desc2->hdr1, TALITOS_DESC_SIZE,
                                            DMA_BIDIRECTIONAL);
@@ -1909,8 +1928,11 @@ static struct talitos_edesc *ahash_edesc_alloc(struct ahash_request *areq,
 static int ahash_init(struct ahash_request *areq)
 {
         struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
+        struct talitos_ctx *ctx = crypto_ahash_ctx(tfm);
+        struct device *dev = ctx->dev;
         struct talitos_ahash_req_ctx *req_ctx = ahash_request_ctx(areq);
         unsigned int size;
+        dma_addr_t dma;
 
         /* Initialize the context */
         req_ctx->buf_idx = 0;
@@ -1922,6 +1944,10 @@ static int ahash_init(struct ahash_request *areq)
                         : TALITOS_MDEU_CONTEXT_SIZE_SHA384_SHA512;
         req_ctx->hw_context_size = size;
 
+        dma = dma_map_single(dev, req_ctx->hw_context, req_ctx->hw_context_size,
+                             DMA_TO_DEVICE);
+        dma_unmap_single(dev, dma, req_ctx->hw_context_size, DMA_TO_DEVICE);
+
         return 0;
 }
 
@@ -1933,9 +1959,6 @@ static int ahash_init_sha224_swinit(struct ahash_request *areq)
 {
         struct talitos_ahash_req_ctx *req_ctx = ahash_request_ctx(areq);
 
-        ahash_init(areq);
-        req_ctx->swinit = 1;/* prevent h/w initting context with sha256 values*/
-
         req_ctx->hw_context[0] = SHA224_H0;
         req_ctx->hw_context[1] = SHA224_H1;
         req_ctx->hw_context[2] = SHA224_H2;
@@ -1949,6 +1972,9 @@ static int ahash_init_sha224_swinit(struct ahash_request *areq)
         req_ctx->hw_context[8] = 0;
         req_ctx->hw_context[9] = 0;
 
+        ahash_init(areq);
+        req_ctx->swinit = 1;/* prevent h/w initting context with sha256 values*/
+
         return 0;
 }
 
@@ -2105,6 +2131,14 @@ static int ahash_export(struct ahash_request *areq, void *out)
 {
         struct talitos_ahash_req_ctx *req_ctx = ahash_request_ctx(areq);
         struct talitos_export_state *export = out;
+        struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
+        struct talitos_ctx *ctx = crypto_ahash_ctx(tfm);
+        struct device *dev = ctx->dev;
+        dma_addr_t dma;
+
+        dma = dma_map_single(dev, req_ctx->hw_context, req_ctx->hw_context_size,
+                             DMA_FROM_DEVICE);
+        dma_unmap_single(dev, dma, req_ctx->hw_context_size, DMA_FROM_DEVICE);
 
         memcpy(export->hw_context, req_ctx->hw_context,
                req_ctx->hw_context_size);
@@ -2122,8 +2156,11 @@ static int ahash_import(struct ahash_request *areq, const void *in)
 {
         struct talitos_ahash_req_ctx *req_ctx = ahash_request_ctx(areq);
         struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
+        struct talitos_ctx *ctx = crypto_ahash_ctx(tfm);
+        struct device *dev = ctx->dev;
         const struct talitos_export_state *export = in;
         unsigned int size;
+        dma_addr_t dma;
 
         memset(req_ctx, 0, sizeof(*req_ctx));
         size = (crypto_ahash_digestsize(tfm) <= SHA256_DIGEST_SIZE)
@@ -2138,6 +2175,10 @@ static int ahash_import(struct ahash_request *areq, const void *in)
         req_ctx->to_hash_later = export->to_hash_later;
         req_ctx->nbuf = export->nbuf;
 
+        dma = dma_map_single(dev, req_ctx->hw_context, req_ctx->hw_context_size,
+                             DMA_TO_DEVICE);
+        dma_unmap_single(dev, dma, req_ctx->hw_context_size, DMA_TO_DEVICE);
+
         return 0;
 }