[net-next PATCH 10/27] arch/hexagon: Add option to skip DMA sync as a part of mapping
From: Alexander Duyck <hidden>
Date: 2016-10-25 21:38:23
Also in:
intel-wired-lan, linux-mm, netdev
Subsystem:
qualcomm hexagon architecture, the rest · Maintainers:
Brian Cain, 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 later via a sync_for_cpu or sync_for_device call. Cc: Richard Kuo <redacted> Cc: linux-hexagon@vger.kernel.org Signed-off-by: Alexander Duyck <redacted> --- 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 b901778..dbc4f10 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; }