Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit fc1b138d authored by Alexander Duyck's avatar Alexander Duyck Committed by Linus Torvalds
Browse files

arch/arm: add option to skip sync on DMA map and unmap 

The use of DMA_ATTR_SKIP_CPU_SYNC was not consistent across all of the
DMA APIs in the arch/arm folder.  This change is meant to correct that
so that we get consistent behavior.

Link: http://lkml.kernel.org/r/20161110113424.76501.2715.stgit@ahduyck-blue-test.jf.intel.com


Signed-off-by: default avatarAlexander Duyck <alexander.h.duyck@intel.com>
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 8a3385d2

arch/arm/common/dmabounce.c

+10 −6
Original line number Diff line number Diff line
@@ -243,7 +243,8 @@ static int needs_bounce(struct device *dev, dma_addr_t dma_addr, size_t size) 
}



static inline dma_addr_t map_single(struct device *dev, void *ptr, size_t size,

		enum dma_data_direction dir)

				    enum dma_data_direction dir,

				    unsigned long attrs)

{

	struct dmabounce_device_info *device_info = dev->archdata.dmabounce;

	struct safe_buffer *buf;
@@ -262,7 +263,8 @@ static inline dma_addr_t map_single(struct device *dev, void *ptr, size_t size, 
		__func__, buf->ptr, virt_to_dma(dev, buf->ptr),

		buf->safe, buf->safe_dma_addr);



	if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL) {

	if ((dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL) &&

	    !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) {

		dev_dbg(dev, "%s: copy unsafe %p to safe %p, size %d\n",

			__func__, ptr, buf->safe, size);

		memcpy(buf->safe, ptr, size);
@@ -272,7 +274,8 @@ static inline dma_addr_t map_single(struct device *dev, void *ptr, size_t size, 
}



static inline void unmap_single(struct device *dev, struct safe_buffer *buf,

		size_t size, enum dma_data_direction dir)

				size_t size, enum dma_data_direction dir,

				unsigned long attrs)

{

	BUG_ON(buf->size != size);

	BUG_ON(buf->direction != dir);
@@ -283,7 +286,8 @@ static inline void unmap_single(struct device *dev, struct safe_buffer *buf, 


	DO_STATS(dev->archdata.dmabounce->bounce_count++);



	if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL) {

	if ((dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL) &&

	    !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) {

		void *ptr = buf->ptr;



		dev_dbg(dev, "%s: copy back safe %p to unsafe %p size %d\n",
@@ -334,7 +338,7 @@ static dma_addr_t dmabounce_map_page(struct device *dev, struct page *page, 
		return DMA_ERROR_CODE;

	}



	return map_single(dev, page_address(page) + offset, size, dir);

	return map_single(dev, page_address(page) + offset, size, dir, attrs);

}



/*
@@ -357,7 +361,7 @@ static void dmabounce_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t 
		return;

	}



	unmap_single(dev, buf, size, dir);

	unmap_single(dev, buf, size, dir, attrs);

}



static int __dmabounce_sync_for_cpu(struct device *dev, dma_addr_t addr,