From 273d4428f8c4cc94c9598f8bcc006ec2e8c654ea Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Sun, 11 Sep 2016 05:04:00 -0300 Subject: Linux-libre 4.7.2-gnu --- arch/arm/mm/dma-mapping.c | 62 ++++++++++++++++++++++++++++++++--------------- 1 file changed, 42 insertions(+), 20 deletions(-) (limited to 'arch/arm/mm/dma-mapping.c') diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index ff7ed5697..d2485c749 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -49,6 +49,7 @@ struct arm_dma_alloc_args { pgprot_t prot; const void *caller; bool want_vaddr; + int coherent_flag; }; struct arm_dma_free_args { @@ -59,6 +60,9 @@ struct arm_dma_free_args { bool want_vaddr; }; +#define NORMAL 0 +#define COHERENT 1 + struct arm_dma_allocator { void *(*alloc)(struct arm_dma_alloc_args *args, struct page **ret_page); @@ -272,7 +276,7 @@ static u64 get_coherent_dma_mask(struct device *dev) return mask; } -static void __dma_clear_buffer(struct page *page, size_t size) +static void __dma_clear_buffer(struct page *page, size_t size, int coherent_flag) { /* * Ensure that the allocated pages are zeroed, and that any data @@ -284,17 +288,21 @@ static void __dma_clear_buffer(struct page *page, size_t size) while (size > 0) { void *ptr = kmap_atomic(page); memset(ptr, 0, PAGE_SIZE); - dmac_flush_range(ptr, ptr + PAGE_SIZE); + if (coherent_flag != COHERENT) + dmac_flush_range(ptr, ptr + PAGE_SIZE); kunmap_atomic(ptr); page++; size -= PAGE_SIZE; } - outer_flush_range(base, end); + if (coherent_flag != COHERENT) + outer_flush_range(base, end); } else { void *ptr = page_address(page); memset(ptr, 0, size); - dmac_flush_range(ptr, ptr + size); - outer_flush_range(__pa(ptr), __pa(ptr) + size); + if (coherent_flag != COHERENT) { + dmac_flush_range(ptr, ptr + size); + outer_flush_range(__pa(ptr), __pa(ptr) + size); + } } } @@ -302,7 +310,8 @@ static void __dma_clear_buffer(struct page *page, size_t size) * Allocate a DMA buffer for 'dev' of size 'size' using the * specified gfp mask. Note that 'size' must be page aligned. */ -static struct page *__dma_alloc_buffer(struct device *dev, size_t size, gfp_t gfp) +static struct page *__dma_alloc_buffer(struct device *dev, size_t size, + gfp_t gfp, int coherent_flag) { unsigned long order = get_order(size); struct page *page, *p, *e; @@ -318,7 +327,7 @@ static struct page *__dma_alloc_buffer(struct device *dev, size_t size, gfp_t gf for (p = page + (size >> PAGE_SHIFT), e = page + (1 << order); p < e; p++) __free_page(p); - __dma_clear_buffer(page, size); + __dma_clear_buffer(page, size, coherent_flag); return page; } @@ -340,7 +349,8 @@ static void __dma_free_buffer(struct page *page, size_t size) static void *__alloc_from_contiguous(struct device *dev, size_t size, pgprot_t prot, struct page **ret_page, - const void *caller, bool want_vaddr); + const void *caller, bool want_vaddr, + int coherent_flag); static void *__alloc_remap_buffer(struct device *dev, size_t size, gfp_t gfp, pgprot_t prot, struct page **ret_page, @@ -405,10 +415,13 @@ static int __init atomic_pool_init(void) atomic_pool = gen_pool_create(PAGE_SHIFT, -1); if (!atomic_pool) goto out; - + /* + * The atomic pool is only used for non-coherent allocations + * so we must pass NORMAL for coherent_flag. + */ if (dev_get_cma_area(NULL)) ptr = __alloc_from_contiguous(NULL, atomic_pool_size, prot, - &page, atomic_pool_init, true); + &page, atomic_pool_init, true, NORMAL); else ptr = __alloc_remap_buffer(NULL, atomic_pool_size, gfp, prot, &page, atomic_pool_init, true); @@ -522,7 +535,11 @@ static void *__alloc_remap_buffer(struct device *dev, size_t size, gfp_t gfp, { struct page *page; void *ptr = NULL; - page = __dma_alloc_buffer(dev, size, gfp); + /* + * __alloc_remap_buffer is only called when the device is + * non-coherent + */ + page = __dma_alloc_buffer(dev, size, gfp, NORMAL); if (!page) return NULL; if (!want_vaddr) @@ -577,7 +594,8 @@ static int __free_from_pool(void *start, size_t size) static void *__alloc_from_contiguous(struct device *dev, size_t size, pgprot_t prot, struct page **ret_page, - const void *caller, bool want_vaddr) + const void *caller, bool want_vaddr, + int coherent_flag) { unsigned long order = get_order(size); size_t count = size >> PAGE_SHIFT; @@ -588,7 +606,7 @@ static void *__alloc_from_contiguous(struct device *dev, size_t size, if (!page) return NULL; - __dma_clear_buffer(page, size); + __dma_clear_buffer(page, size, coherent_flag); if (!want_vaddr) goto out; @@ -638,7 +656,7 @@ static inline pgprot_t __get_dma_pgprot(struct dma_attrs *attrs, pgprot_t prot) #define __get_dma_pgprot(attrs, prot) __pgprot(0) #define __alloc_remap_buffer(dev, size, gfp, prot, ret, c, wv) NULL #define __alloc_from_pool(size, ret_page) NULL -#define __alloc_from_contiguous(dev, size, prot, ret, c, wv) NULL +#define __alloc_from_contiguous(dev, size, prot, ret, c, wv, coherent_flag) NULL #define __free_from_pool(cpu_addr, size) do { } while (0) #define __free_from_contiguous(dev, page, cpu_addr, size, wv) do { } while (0) #define __dma_free_remap(cpu_addr, size) do { } while (0) @@ -649,7 +667,8 @@ static void *__alloc_simple_buffer(struct device *dev, size_t size, gfp_t gfp, struct page **ret_page) { struct page *page; - page = __dma_alloc_buffer(dev, size, gfp); + /* __alloc_simple_buffer is only called when the device is coherent */ + page = __dma_alloc_buffer(dev, size, gfp, COHERENT); if (!page) return NULL; @@ -679,7 +698,7 @@ static void *cma_allocator_alloc(struct arm_dma_alloc_args *args, { return __alloc_from_contiguous(args->dev, args->size, args->prot, ret_page, args->caller, - args->want_vaddr); + args->want_vaddr, args->coherent_flag); } static void cma_allocator_free(struct arm_dma_free_args *args) @@ -746,6 +765,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, .prot = prot, .caller = caller, .want_vaddr = !dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs), + .coherent_flag = is_coherent ? COHERENT : NORMAL, }; #ifdef CONFIG_DMA_API_DEBUG @@ -1253,7 +1273,8 @@ static inline void __free_iova(struct dma_iommu_mapping *mapping, static const int iommu_order_array[] = { 9, 8, 4, 0 }; static struct page **__iommu_alloc_buffer(struct device *dev, size_t size, - gfp_t gfp, struct dma_attrs *attrs) + gfp_t gfp, struct dma_attrs *attrs, + int coherent_flag) { struct page **pages; int count = size >> PAGE_SHIFT; @@ -1277,7 +1298,7 @@ static struct page **__iommu_alloc_buffer(struct device *dev, size_t size, if (!page) goto error; - __dma_clear_buffer(page, size); + __dma_clear_buffer(page, size, coherent_flag); for (i = 0; i < count; i++) pages[i] = page + i; @@ -1327,7 +1348,7 @@ static struct page **__iommu_alloc_buffer(struct device *dev, size_t size, pages[i + j] = pages[i] + j; } - __dma_clear_buffer(pages[i], PAGE_SIZE << order); + __dma_clear_buffer(pages[i], PAGE_SIZE << order, coherent_flag); i += 1 << order; count -= 1 << order; } @@ -1505,7 +1526,8 @@ static void *arm_iommu_alloc_attrs(struct device *dev, size_t size, */ gfp &= ~(__GFP_COMP); - pages = __iommu_alloc_buffer(dev, size, gfp, attrs); + /* For now always consider we are in a non-coherent case */ + pages = __iommu_alloc_buffer(dev, size, gfp, attrs, NORMAL); if (!pages) return NULL; -- cgit v1.2.3-54-g00ecf