Commit 5140d234 authored by Alexander Duyck's avatar Alexander Duyck Committed by Linus Torvalds

arch/m68k: 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/20161110113457.76501.77603.stgit@ahduyck-blue-test.jf.intel.comSigned-off-by: default avatarAlexander Duyck <alexander.h.duyck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent b8a346dd
...@@ -134,7 +134,9 @@ static dma_addr_t m68k_dma_map_page(struct device *dev, struct page *page, ...@@ -134,7 +134,9 @@ static dma_addr_t m68k_dma_map_page(struct device *dev, struct page *page,
{ {
dma_addr_t handle = page_to_phys(page) + offset; dma_addr_t handle = page_to_phys(page) + offset;
dma_sync_single_for_device(dev, handle, size, dir); if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
dma_sync_single_for_device(dev, handle, size, dir);
return handle; return handle;
} }
...@@ -146,6 +148,10 @@ static int m68k_dma_map_sg(struct device *dev, struct scatterlist *sglist, ...@@ -146,6 +148,10 @@ static int m68k_dma_map_sg(struct device *dev, struct scatterlist *sglist,
for_each_sg(sglist, sg, nents, i) { for_each_sg(sglist, sg, nents, i) {
sg->dma_address = sg_phys(sg); sg->dma_address = sg_phys(sg);
if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
continue;
dma_sync_single_for_device(dev, sg->dma_address, sg->length, dma_sync_single_for_device(dev, sg->dma_address, sg->length,
dir); dir);
} }
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment