arch/blackfin: add option to skip sync on DMA map
authorAlexander Duyck <alexander.h.duyck@intel.com>
Wed, 14 Dec 2016 23:04:38 +0000 (15:04 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 15 Dec 2016 00:04:07 +0000 (16:04 -0800)
The use of DMA_ATTR_SKIP_CPU_SYNC was not consistent across all of the
DMA APIs in the arch/arm folder.  This change is meant to correct that
so that we get consistent behavior.

Link: http://lkml.kernel.org/r/20161110113436.76501.13386.stgit@ahduyck-blue-test.jf.intel.com
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: Steven Miao <realmz6@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/blackfin/kernel/dma-mapping.c

index 53fbbb61aa86b3483a5b0bb989604b26f11cdd0b..a27a74a18fb0f9413ae63cf9b5663b2d7af658d1 100644 (file)
@@ -118,6 +118,10 @@ static int bfin_dma_map_sg(struct device *dev, struct scatterlist *sg_list,
 
        for_each_sg(sg_list, sg, nents, i) {
                sg->dma_address = (dma_addr_t) sg_virt(sg);
+
+               if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
+                       continue;
+
                __dma_sync(sg_dma_address(sg), sg_dma_len(sg), direction);
        }
 
@@ -143,7 +147,9 @@ static dma_addr_t bfin_dma_map_page(struct device *dev, struct page *page,
 {
        dma_addr_t handle = (dma_addr_t)(page_address(page) + offset);
 
-       _dma_sync(handle, size, dir);
+       if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+               _dma_sync(handle, size, dir);
+
        return handle;
 }