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>

diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c
index bb44df1..447cb8b 100644 (file)
--- 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;
 }