[mm PATCH v3 19/23] arch/xtensa: Add option to skip DMA sync as a part of mapping
From: Alexander Duyck <hidden>
Date: 2016-11-10 17:37:09
Also in:
lkml, netdev
Subsystem:
tensilica xtensa port (xtensa), the rest · Maintainers:
Chris Zankel, Max Filippov, Linus Torvalds
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: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Alexander Duyck <redacted> --- arch/xtensa/kernel/pci-dma.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/arch/xtensa/kernel/pci-dma.c b/arch/xtensa/kernel/pci-dma.c
index 1e68806..6a16dec 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, --
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