Commit 214fdbe7 authored by Laura Abbott's avatar Laura Abbott Committed by Catalin Marinas
Browse files

arm64: Support DMA_ATTR_WRITE_COMBINE 



DMA_ATTR_WRITE_COMBINE is currently ignored. Set the pgprot
appropriately for non coherent opperations.

Signed-off-by: default avatarLaura Abbott <lauraa@codeaurora.org>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 6e8d7968

arch/arm64/mm/dma-mapping.c

+12 −2
Original line number Diff line number Diff line
@@ -30,6 +30,16 @@ 
struct dma_map_ops *dma_ops;

EXPORT_SYMBOL(dma_ops);



static pgprot_t __get_dma_pgprot(struct dma_attrs *attrs, pgprot_t prot,

				 bool coherent)

{

	if (dma_get_attr(DMA_ATTR_WRITE_COMBINE, attrs))

		return pgprot_writecombine(prot);

	else if (!coherent)

		return pgprot_dmacoherent(prot);

	return prot;

}



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

				  dma_addr_t *dma_handle, gfp_t flags,

				  struct dma_attrs *attrs)
@@ -104,7 +114,7 @@ static void *__dma_alloc_noncoherent(struct device *dev, size_t size, 
	for (i = 0; i < (size >> PAGE_SHIFT); i++)

		map[i] = page + i;

	coherent_ptr = vmap(map, size >> PAGE_SHIFT, VM_MAP,

			    pgprot_dmacoherent(pgprot_default));

			    __get_dma_pgprot(attrs, pgprot_default, false));

	kfree(map);

	if (!coherent_ptr)

		goto no_map;
@@ -250,7 +260,7 @@ static int __swiotlb_mmap_noncoherent(struct device *dev, 
		void *cpu_addr, dma_addr_t dma_addr, size_t size,

		struct dma_attrs *attrs)

{

	vma->vm_page_prot = pgprot_dmacoherent(vma->vm_page_prot);

	vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot, false);

	return __dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);

}