This change allows us to pass DMA_ATTR_SKIP_CPU_SYNC which allows us to
avoid invoking cache line invalidation if the driver will just handle it
via a sync_for_cpu or sync_for_device call.
Cc: Ley Foon Tan <lftan@xxxxxxxxxx>
Signed-off-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx>
---
arch/nios2/mm/dma-mapping.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/arch/nios2/mm/dma-mapping.c b/arch/nios2/mm/dma-mapping.c
index d800fad..b83e723 100644
--- a/arch/nios2/mm/dma-mapping.c
+++ b/arch/nios2/mm/dma-mapping.c
@@ -102,7 +102,9 @@ static int nios2_dma_map_sg(struct device *dev, struct scatterlist *sg,
addr = sg_virt(sg);
if (addr) {
- __dma_sync_for_device(addr, sg->length, direction);
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+ __dma_sync_for_device(addr, sg->length,
+ direction);
sg->dma_address = sg_phys(sg);
}
}
@@ -117,7 +119,9 @@ static dma_addr_t nios2_dma_map_page(struct device *dev, struct page *page,
{
void *addr = page_address(page) + offset;
- __dma_sync_for_device(addr, size, direction);
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+ __dma_sync_for_device(addr, size, direction);
+
return page_to_phys(page) + offset;
}
@@ -125,7 +129,8 @@ static void nios2_dma_unmap_page(struct device *dev, dma_addr_t dma_address,
size_t size, enum dma_data_direction direction,
unsigned long attrs)
{
- __dma_sync_for_cpu(phys_to_virt(dma_address), size, direction);
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+ __dma_sync_for_cpu(phys_to_virt(dma_address), size, direction);
}
static void nios2_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
@@ -138,6 +143,9 @@ static void nios2_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
if (direction == DMA_TO_DEVICE)
return;
+ if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
+ return;
+
for_each_sg(sg, sg, nhwentries, i) {
addr = sg_virt(sg);
if (addr)
--
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