_dma_page_cpu_to_dev() treat DMA_BIDIRECTIONAL similar to DMA_TO_DEVICE which means that destination buffer is device memory,means cpu may have written some data to source buffer and data may be in cache line.For cleaner operation we need to call outer_flush_range() which will clean and invalidate outer cache lines.
Signed-off-by: Sanjeev Sharma <[email protected]> --- arch/arm/mm/dma-mapping.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index e62400e..e195235 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -850,12 +850,20 @@ static void __dma_page_cpu_to_dev(struct page *page, unsigned long off, dma_cache_maint_page(page, off, size, dir, dmac_map_area); paddr = page_to_phys(page) + off; - if (dir == DMA_FROM_DEVICE) { - outer_inv_range(paddr, paddr + size); - } else { - outer_clean_range(paddr, paddr + size); + + switch (dir) { + case DMA_FROM_DEVICE: + outer_inv_range(paddr, paddr + size); + break; + case DMA_TO_DEVICE: + outer_clean_range(paddr, paddr + size); + break; + case DMA_BIDIRECTIONAL: + outer_flush_range(paddr, paddr + size); + break; + default: + break; } - /* FIXME: non-speculating: flush on bidirectional mappings? */ } static void __dma_page_dev_to_cpu(struct page *page, unsigned long off, -- 1.7.11.7 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
