From: Shawn Lin <shawn.lin@rock-chips.com>
Date: Wed, 8 Jul 2015 09:32:06 +0000 (+0800)
Subject: arm64: dma-mapping: conditional skip map_sg by attrs
X-Git-Tag: firefly_0821_release~3931
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=b80f2f689937dd657ee2587f3951991e19ea1803;p=firefly-linux-kernel-4.4.55.git

arm64: dma-mapping: conditional skip map_sg by attrs

Add if statement(DMA_ATTR_SKIP_CPU_SYNC) for __swiotlb_map_sg_attrs
to skip invalidating each sg element

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
---

diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index aff368c35d62..dc573621e41d 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -224,10 +224,11 @@ static int __swiotlb_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
 	int i, ret;
 
 	ret = swiotlb_map_sg_attrs(dev, sgl, nelems, dir, attrs);
-	for_each_sg(sgl, sg, ret, i)
-		__dma_map_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
-			       sg->length, dir);
-
+	if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs)) {
+		for_each_sg(sgl, sg, ret, i)
+			__dma_map_area(phys_to_virt(dma_to_phys(dev, sg->dma_address)),
+					sg->length, dir);
+	}
 	return ret;
 }