diff options
| -rw-r--r-- | arch/arm/include/asm/dma-mapping.h | 39 | ||||
| -rw-r--r-- | arch/arm/mm/dma-mapping.c | 34 |
2 files changed, 55 insertions, 18 deletions
diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h index e850f5c1607..256ee1c9f51 100644 --- a/arch/arm/include/asm/dma-mapping.h +++ b/arch/arm/include/asm/dma-mapping.h @@ -57,46 +57,57 @@ static inline dma_addr_t virt_to_dma(struct device *dev, void *addr) #endif /* - * Private support functions: these are not part of the API and are - * liable to change. Drivers must not use these. - */ -extern void dma_cache_maint(const void *kaddr, size_t size, int rw); -extern void dma_cache_maint_page(struct page *page, unsigned long offset, - size_t size, int rw); - -/* * The DMA API is built upon the notion of "buffer ownership". A buffer * is either exclusively owned by the CPU (and therefore may be accessed * by it) or exclusively owned by the DMA device. These helper functions * represent the transitions between these two ownership states. * - * As above, these are private support functions and not part of the API. - * Drivers must not use these. + * Note, however, that on later ARMs, this notion does not work due to + * speculative prefetches. We model our approach on the assumption that + * the CPU does do speculative prefetches, which means we clean caches + * before transfers and delay cache invalidation until transfer completion. + * + * Private support functions: these are not part of the API and are + * liable to change. Drivers must not use these. */ static inline void __dma_single_cpu_to_dev(const void *kaddr, size_t size, enum dma_data_direction dir) { + extern void ___dma_single_cpu_to_dev(const void *, size_t, + enum dma_data_direction); + if (!arch_is_coherent()) - dma_cache_maint(kaddr, size, dir); + ___dma_single_cpu_to_dev(kaddr, size, dir); } static inline void __dma_single_dev_to_cpu(const void *kaddr, size_t size, enum dma_data_direction dir) { - /* nothing to do */ + extern void ___dma_single_dev_to_cpu(const void *, size_t, + enum dma_data_direction); + + if (!arch_is_coherent()) + ___dma_single_dev_to_cpu(kaddr, size, dir); } static inline void __dma_page_cpu_to_dev(struct page *page, unsigned long off, size_t size, enum dma_data_direction dir) { + extern void ___dma_page_cpu_to_dev(struct page *, unsigned long, + size_t, enum dma_data_direction); + if (!arch_is_coherent()) - dma_cache_maint_page(page, off, size, dir); + ___dma_page_cpu_to_dev(page, off, size, dir); } static inline void __dma_page_dev_to_cpu(struct page *page, unsigned long off, size_t size, enum dma_data_direction dir) { - /* nothing to do */ + extern void ___dma_page_dev_to_cpu(struct page *, unsigned long, + size_t, enum dma_data_direction); + + if (!arch_is_coherent()) + ___dma_page_dev_to_cpu(page, off, size, dir); } /* diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index a316c945952..bbf87880b91 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -404,7 +404,7 @@ EXPORT_SYMBOL(dma_free_coherent); * platforms with CONFIG_DMABOUNCE. * Use the driver DMA support - see dma-mapping.h (dma_sync_*) */ -void dma_cache_maint(const void *start, size_t size, int direction) +static void dma_cache_maint(const void *start, size_t size, int direction) { void (*inner_op)(const void *, const void *); void (*outer_op)(unsigned long, unsigned long); @@ -431,7 +431,20 @@ void dma_cache_maint(const void *start, size_t size, int direction) inner_op(start, start + size); outer_op(__pa(start), __pa(start) + size); } -EXPORT_SYMBOL(dma_cache_maint); + +void ___dma_single_cpu_to_dev(const void *kaddr, size_t size, + enum dma_data_direction dir) +{ + dma_cache_maint(kaddr, size, dir); +} +EXPORT_SYMBOL(___dma_single_cpu_to_dev); + +void ___dma_single_dev_to_cpu(const void *kaddr, size_t size, + enum dma_data_direction dir) +{ + /* nothing to do */ +} +EXPORT_SYMBOL(___dma_single_dev_to_cpu); static void dma_cache_maint_contiguous(struct page *page, unsigned long offset, size_t size, int direction) @@ -474,7 +487,7 @@ static void dma_cache_maint_contiguous(struct page *page, unsigned long offset, outer_op(paddr, paddr + size); } -void dma_cache_maint_page(struct page *page, unsigned long offset, +static void dma_cache_maint_page(struct page *page, unsigned long offset, size_t size, int dir) { /* @@ -499,7 +512,20 @@ void dma_cache_maint_page(struct page *page, unsigned long offset, left -= len; } while (left); } -EXPORT_SYMBOL(dma_cache_maint_page); + +void ___dma_page_cpu_to_dev(struct page *page, unsigned long off, + size_t size, enum dma_data_direction dir) +{ + dma_cache_maint_page(page, off, size, dir); +} +EXPORT_SYMBOL(___dma_page_cpu_to_dev); + +void ___dma_page_dev_to_cpu(struct page *page, unsigned long off, + size_t size, enum dma_data_direction dir) +{ + /* nothing to do */ +} +EXPORT_SYMBOL(___dma_page_dev_to_cpu); /** * dma_map_sg - map a set of SG buffers for streaming mode DMA |