Unverified Commit a999933d authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Paul Burton
Browse files

MIPS: remove mips_swiotlb_ops 



mips_swiotlb_ops differs from the generic swiotlb_dma_ops only in that
it contains a mb() barrier after each operations that maps or syncs
dma memory to the device.

The dma operations are defined to not be memory barriers, but instead
the write* operations to kick the DMA off are supposed to contain them.

For mips this handled by war_io_reorder_wmb(), which evaluates to the
stronger wmb() instead of the pure compiler barrier barrier() for
just those platforms that use swiotlb, so I think we are covered
properly.

[paul.burton@mips.com:
  - Include linux/swiotlb.h to fix build failures for configs with
    CONFIG_SWIOTLB=y.]

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarPaul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20038/
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: linux-mips@linux-mips.org
Cc: iommu@lists.linux-foundation.org
Cc: linux-kernel@vger.kernel.org
parent d4da0e97

arch/mips/include/asm/dma-mapping.h

+3 −2
Original line number Diff line number Diff line
@@ -2,15 +2,16 @@ 
#ifndef _ASM_DMA_MAPPING_H

#define _ASM_DMA_MAPPING_H



#include <linux/swiotlb.h>



extern const struct dma_map_ops jazz_dma_ops;

extern const struct dma_map_ops mips_swiotlb_ops;



static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)

{

#if defined(CONFIG_MACH_JAZZ)

	return &jazz_dma_ops;

#elif defined(CONFIG_SWIOTLB)

	return &mips_swiotlb_ops;

	return &swiotlb_dma_ops;

#elif defined(CONFIG_DMA_NONCOHERENT_OPS)

	return &dma_noncoherent_ops;

#else

arch/mips/mm/Makefile

+0 −1
Original line number Diff line number Diff line
@@ -18,7 +18,6 @@ obj-$(CONFIG_64BIT) += pgtable-64.o 
obj-$(CONFIG_HIGHMEM)		+= highmem.o

obj-$(CONFIG_HUGETLB_PAGE)	+= hugetlbpage.o

obj-$(CONFIG_DMA_NONCOHERENT)	+= dma-noncoherent.o

obj-$(CONFIG_SWIOTLB)		+= dma-swiotlb.o



obj-$(CONFIG_CPU_R4K_CACHE_TLB) += c-r4k.o cex-gen.o tlb-r4k.o

obj-$(CONFIG_CPU_R3000)		+= c-r3k.o tlb-r3k.o

arch/mips/mm/dma-swiotlb.c

deleted100644 → 0
+0 −61
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

#include <linux/dma-mapping.h>

#include <linux/swiotlb.h>



static void *mips_swiotlb_alloc(struct device *dev, size_t size,

		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)

{

	void *ret = swiotlb_alloc(dev, size, dma_handle, gfp, attrs);



	mb();

	return ret;

}



static dma_addr_t mips_swiotlb_map_page(struct device *dev,

		struct page *page, unsigned long offset, size_t size,

		enum dma_data_direction dir, unsigned long attrs)

{

	dma_addr_t daddr = swiotlb_map_page(dev, page, offset, size,

					dir, attrs);

	mb();

	return daddr;

}



static int mips_swiotlb_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, attrs);

	mb();



	return r;

}



static void mips_swiotlb_sync_single_for_device(struct device *dev,

		dma_addr_t dma_handle, size_t size, enum dma_data_direction dir)

{

	swiotlb_sync_single_for_device(dev, dma_handle, size, dir);

	mb();

}



static void mips_swiotlb_sync_sg_for_device(struct device *dev,

		struct scatterlist *sg, int nents, enum dma_data_direction dir)

{

	swiotlb_sync_sg_for_device(dev, sg, nents, dir);

	mb();

}



const struct dma_map_ops mips_swiotlb_ops = {

	.alloc			= mips_swiotlb_alloc,

	.free			= swiotlb_free,

	.map_page		= mips_swiotlb_map_page,

	.unmap_page		= swiotlb_unmap_page,

	.map_sg			= mips_swiotlb_map_sg,

	.unmap_sg		= swiotlb_unmap_sg_attrs,

	.sync_single_for_cpu	= swiotlb_sync_single_for_cpu,

	.sync_single_for_device	= mips_swiotlb_sync_single_for_device,

	.sync_sg_for_cpu	= swiotlb_sync_sg_for_cpu,

	.sync_sg_for_device	= mips_swiotlb_sync_sg_for_device,

	.mapping_error		= swiotlb_dma_mapping_error,

	.dma_supported		= swiotlb_dma_supported,

};

EXPORT_SYMBOL(mips_swiotlb_ops);

CRA Git | Maintained and supported by SUSTech CRA and CCSE