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| author | Alexander Duyck <alexander.h.duyck@intel.com> | 2016-12-15 02:04:55 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-15 03:04:07 +0300 |
| commit | 98ac2fc274e07a22bea43682cf8998f47ffea9d0 (patch) | |
| tree | 4ddf06f30ac96c18d67dfe4789e1121a4c6b7a24 /arch | |
| parent | 38bdbdc7e391f5326a9f27f0bc8be0c175a73567 (diff) | |
| download | linux-98ac2fc274e07a22bea43682cf8998f47ffea9d0.tar.xz | |
arch/microblaze: add option to skip DMA sync as a part of map and unmap
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.
Link: http://lkml.kernel.org/r/20161110113508.76501.77583.stgit@ahduyck-blue-test.jf.intel.com
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: Michal Simek <monstr@monstr.eu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/microblaze/kernel/dma.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/arch/microblaze/kernel/dma.c b/arch/microblaze/kernel/dma.c index ec04dc1e2527..818daf230eb4 100644 --- a/arch/microblaze/kernel/dma.c +++ b/arch/microblaze/kernel/dma.c @@ -61,6 +61,10 @@ static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, /* FIXME this part of code is untested */ for_each_sg(sgl, sg, nents, i) { sg->dma_address = sg_phys(sg); + + if (attrs & DMA_ATTR_SKIP_CPU_SYNC) + continue; + __dma_sync(page_to_phys(sg_page(sg)) + sg->offset, sg->length, direction); } @@ -80,7 +84,8 @@ static inline dma_addr_t dma_direct_map_page(struct device *dev, enum dma_data_direction direction, unsigned long attrs) { - __dma_sync(page_to_phys(page) + offset, size, direction); + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + __dma_sync(page_to_phys(page) + offset, size, direction); return page_to_phys(page) + offset; } @@ -95,7 +100,8 @@ static inline void dma_direct_unmap_page(struct device *dev, * phys_to_virt is here because in __dma_sync_page is __virt_to_phys and * dma_address is physical address */ - __dma_sync(dma_address, size, direction); + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + __dma_sync(dma_address, size, direction); } static inline void |