From b8a346dd472af45e1ee8cbc77101dad0b836210b Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Wed, 14 Dec 2016 15:04:46 -0800 Subject: [PATCH] arch/hexagon: 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 later via a sync_for_cpu or sync_for_device call. Link: http://lkml.kernel.org/r/20161110113452.76501.45864.stgit@ahduyck-blue-test.jf.intel.com Signed-off-by: Alexander Duyck Cc: Richard Kuo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/hexagon/kernel/dma.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/hexagon/kernel/dma.c b/arch/hexagon/kernel/dma.c index b9017785fb71..dbc4f1003da4 100644 --- a/arch/hexagon/kernel/dma.c +++ b/arch/hexagon/kernel/dma.c @@ -119,6 +119,9 @@ static int hexagon_map_sg(struct device *hwdev, struct scatterlist *sg, s->dma_length = s->length; + if (attrs & DMA_ATTR_SKIP_CPU_SYNC) + continue; + flush_dcache_range(dma_addr_to_virt(s->dma_address), dma_addr_to_virt(s->dma_address + s->length)); } @@ -180,7 +183,8 @@ static dma_addr_t hexagon_map_page(struct device *dev, struct page *page, if (!check_addr("map_single", dev, bus, size)) return bad_dma_address; - dma_sync(dma_addr_to_virt(bus), size, dir); + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_sync(dma_addr_to_virt(bus), size, dir); return bus; } -- 2.20.1