From 15237e1f505b3e5c2276f240b01cd2133e110cbc Mon Sep 17 00:00:00 2001 From: Marek Szyprowski Date: Fri, 10 Feb 2012 19:55:20 +0100 Subject: ARM: dma-mapping: move all dma bounce code to separate dma ops structure This patch removes dma bounce hooks from the common dma mapping implementation on ARM architecture and creates a separate set of dma_map_ops for dma bounce devices. Signed-off-by: Marek Szyprowski Acked-by: Kyungmin Park Tested-By: Subash Patel --- arch/arm/mm/dma-mapping.c | 79 +++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 69 insertions(+), 10 deletions(-) (limited to 'arch/arm/mm') diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index b50fa578df81..c94966891dee 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -29,6 +29,75 @@ #include "mm.h" +/* + * 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. + * + * 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_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) +{ + 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_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) +{ + 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); +} + + +static inline dma_addr_t __dma_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, enum dma_data_direction dir) +{ + __dma_page_cpu_to_dev(page, offset, size, dir); + return pfn_to_dma(dev, page_to_pfn(page)) + offset; +} + +static inline void __dma_unmap_page(struct device *dev, dma_addr_t handle, + size_t size, enum dma_data_direction dir) +{ + __dma_page_dev_to_cpu(pfn_to_page(dma_to_pfn(dev, handle)), + handle & ~PAGE_MASK, size, dir); +} + /** * arm_dma_map_page - map a portion of a page for streaming DMA * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices @@ -76,9 +145,6 @@ static inline void arm_dma_sync_single_for_cpu(struct device *dev, { unsigned int offset = handle & (PAGE_SIZE - 1); struct page *page = pfn_to_page(dma_to_pfn(dev, handle-offset)); - if (!dmabounce_sync_for_cpu(dev, handle, size, dir)) - return; - __dma_page_dev_to_cpu(page, offset, size, dir); } @@ -87,9 +153,6 @@ static inline void arm_dma_sync_single_for_device(struct device *dev, { unsigned int offset = handle & (PAGE_SIZE - 1); struct page *page = pfn_to_page(dma_to_pfn(dev, handle-offset)); - if (!dmabounce_sync_for_device(dev, handle, size, dir)) - return; - __dma_page_cpu_to_dev(page, offset, size, dir); } @@ -599,7 +662,6 @@ void ___dma_page_cpu_to_dev(struct page *page, unsigned long off, } /* FIXME: non-speculating: flush on bidirectional mappings? */ } -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) @@ -619,7 +681,6 @@ void ___dma_page_dev_to_cpu(struct page *page, unsigned long off, if (dir != DMA_TO_DEVICE && off == 0 && size >= PAGE_SIZE) set_bit(PG_dcache_clean, &page->flags); } -EXPORT_SYMBOL(___dma_page_dev_to_cpu); /** * arm_dma_map_sg - map a set of SG buffers for streaming mode DMA @@ -737,9 +798,7 @@ static int arm_dma_set_mask(struct device *dev, u64 dma_mask) if (!dev->dma_mask || !dma_supported(dev, dma_mask)) return -EIO; -#ifndef CONFIG_DMABOUNCE *dev->dma_mask = dma_mask; -#endif return 0; } -- cgit v1.2.3