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| author | Alexander Duyck <alexander.h.duyck@intel.com> | 2016-12-14 15:05:21 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-14 16:04:08 -0800 |
| commit | 4bfa135abec99f4b35b5636f56a6db75ce3c64d7 (patch) | |
| tree | d2f9f62c176a96747c97b2f0246af7f113c6707a /arch/xtensa | |
| parent | 33c77e53d838dc27e9d2edec5b6ab6a11861fb32 (diff) | |
| download | linux-4bfa135abec99f4b35b5636f56a6db75ce3c64d7.tar.gz linux-4bfa135abec99f4b35b5636f56a6db75ce3c64d7.tar.bz2 linux-4bfa135abec99f4b35b5636f56a6db75ce3c64d7.zip | |
arch/xtensa: add option to skip DMA sync as a part of mapping
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/20161110113555.76501.52536.stgit@ahduyck-blue-test.jf.intel.com
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/xtensa')
| -rw-r--r-- | arch/xtensa/kernel/pci-dma.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/arch/xtensa/kernel/pci-dma.c b/arch/xtensa/kernel/pci-dma.c index 1e68806d6695..6a16decf278f 100644 --- a/arch/xtensa/kernel/pci-dma.c +++ b/arch/xtensa/kernel/pci-dma.c @@ -189,7 +189,9 @@ static dma_addr_t xtensa_map_page(struct device *dev, struct page *page, { dma_addr_t dma_handle = page_to_phys(page) + offset; - xtensa_sync_single_for_device(dev, dma_handle, size, dir); + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + xtensa_sync_single_for_device(dev, dma_handle, size, dir); + return dma_handle; } @@ -197,7 +199,8 @@ static void xtensa_unmap_page(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction dir, unsigned long attrs) { - xtensa_sync_single_for_cpu(dev, dma_handle, size, dir); + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + xtensa_sync_single_for_cpu(dev, dma_handle, size, dir); } static int xtensa_map_sg(struct device *dev, struct scatterlist *sg, |