From 214fdbe74a096c3aeb7af81d7900e2ab966b10d6 Mon Sep 17 00:00:00 2001 From: Laura Abbott Date: Fri, 14 Mar 2014 19:52:24 +0000 Subject: [PATCH] arm64: Support DMA_ATTR_WRITE_COMBINE DMA_ATTR_WRITE_COMBINE is currently ignored. Set the pgprot appropriately for non coherent opperations. Signed-off-by: Laura Abbott Signed-off-by: Catalin Marinas --- arch/arm64/mm/dma-mapping.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c index 81eea3d..5bba6be 100644 --- a/arch/arm64/mm/dma-mapping.c +++ b/arch/arm64/mm/dma-mapping.c @@ -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); } -- 2.7.4