From 9f318d470e37a470d65449f94a06165ea72dbce1 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Wed, 14 Dec 2016 15:04:58 -0800 Subject: [PATCH] arch/mips: 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/20161110113513.76501.32321.stgit@ahduyck-blue-test.jf.intel.com Signed-off-by: Alexander Duyck Cc: Ralf Baechle Cc: Keguang Zhang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/mips/loongson64/common/dma-swiotlb.c | 2 +- arch/mips/mm/dma-default.c | 8 +++++--- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/arch/mips/loongson64/common/dma-swiotlb.c b/arch/mips/loongson64/common/dma-swiotlb.c index 1a80b6f73ab2..aab4fd681e1f 100644 --- a/arch/mips/loongson64/common/dma-swiotlb.c +++ b/arch/mips/loongson64/common/dma-swiotlb.c @@ -61,7 +61,7 @@ static int loongson_dma_map_sg(struct device *dev, struct scatterlist *sg, int nents, enum dma_data_direction dir, unsigned long attrs) { - int r = swiotlb_map_sg_attrs(dev, sg, nents, dir, 0); + int r = swiotlb_map_sg_attrs(dev, sg, nents, dir, attrs); mb(); return r; diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c index 46d5696c4f27..a39c36af97ad 100644 --- a/arch/mips/mm/dma-default.c +++ b/arch/mips/mm/dma-default.c @@ -293,7 +293,7 @@ static inline void __dma_sync(struct page *page, static void mips_dma_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size, enum dma_data_direction direction, unsigned long attrs) { - if (cpu_needs_post_dma_flush(dev)) + if (cpu_needs_post_dma_flush(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) __dma_sync(dma_addr_to_page(dev, dma_addr), dma_addr & ~PAGE_MASK, size, direction); plat_post_dma_flush(dev); @@ -307,7 +307,8 @@ static int mips_dma_map_sg(struct device *dev, struct scatterlist *sglist, struct scatterlist *sg; for_each_sg(sglist, sg, nents, i) { - if (!plat_device_is_coherent(dev)) + if (!plat_device_is_coherent(dev) && + !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) __dma_sync(sg_page(sg), sg->offset, sg->length, direction); #ifdef CONFIG_NEED_SG_DMA_LENGTH @@ -324,7 +325,7 @@ static dma_addr_t mips_dma_map_page(struct device *dev, struct page *page, unsigned long offset, size_t size, enum dma_data_direction direction, unsigned long attrs) { - if (!plat_device_is_coherent(dev)) + if (!plat_device_is_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) __dma_sync(page, offset, size, direction); return plat_map_dma_mem_page(dev, page) + offset; @@ -339,6 +340,7 @@ static void mips_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, for_each_sg(sglist, sg, nhwentries, i) { if (!plat_device_is_coherent(dev) && + !(attrs & DMA_ATTR_SKIP_CPU_SYNC) && direction != DMA_TO_DEVICE) __dma_sync(sg_page(sg), sg->offset, sg->length, direction); -- 2.30.2