[mm PATCH v2 09/26] arch/frv: Add option to skip sync on DMA map

From: Alexander Duyck
Date: Wed Nov 02 2016 - 13:15:11 EST


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.

Signed-off-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx>
---
arch/frv/mb93090-mb00/pci-dma-nommu.c | 14 ++++++++++----
arch/frv/mb93090-mb00/pci-dma.c | 9 +++++++--
2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/arch/frv/mb93090-mb00/pci-dma-nommu.c b/arch/frv/mb93090-mb00/pci-dma-nommu.c
index 90f2e4c..1876881 100644
--- a/arch/frv/mb93090-mb00/pci-dma-nommu.c
+++ b/arch/frv/mb93090-mb00/pci-dma-nommu.c
@@ -109,16 +109,19 @@ static int frv_dma_map_sg(struct device *dev, struct scatterlist *sglist,
int nents, enum dma_data_direction direction,
unsigned long attrs)
{
- int i;
struct scatterlist *sg;
+ int i;
+
+ BUG_ON(direction == DMA_NONE);
+
+ if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
+ return nents;

for_each_sg(sglist, sg, nents, i) {
frv_cache_wback_inv(sg_dma_address(sg),
sg_dma_address(sg) + sg_dma_len(sg));
}

- BUG_ON(direction == DMA_NONE);
-
return nents;
}

@@ -127,7 +130,10 @@ static dma_addr_t frv_dma_map_page(struct device *dev, struct page *page,
enum dma_data_direction direction, unsigned long attrs)
{
BUG_ON(direction == DMA_NONE);
- flush_dcache_page(page);
+
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+ flush_dcache_page(page);
+
return (dma_addr_t) page_to_phys(page) + offset;
}

diff --git a/arch/frv/mb93090-mb00/pci-dma.c b/arch/frv/mb93090-mb00/pci-dma.c
index f585745..dba7df9 100644
--- a/arch/frv/mb93090-mb00/pci-dma.c
+++ b/arch/frv/mb93090-mb00/pci-dma.c
@@ -40,13 +40,16 @@ static int frv_dma_map_sg(struct device *dev, struct scatterlist *sglist,
int nents, enum dma_data_direction direction,
unsigned long attrs)
{
+ struct scatterlist *sg;
unsigned long dampr2;
void *vaddr;
int i;
- struct scatterlist *sg;

BUG_ON(direction == DMA_NONE);

+ if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
+ return nents;
+
dampr2 = __get_DAMPR(2);

for_each_sg(sglist, sg, nents, i) {
@@ -70,7 +73,9 @@ static dma_addr_t frv_dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction direction, unsigned long attrs)
{
- flush_dcache_page(page);
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+ flush_dcache_page(page);
+
return (dma_addr_t) page_to_phys(page) + offset;
}