ref: https://lkml.org/lkml/2018/5/18/1068 map for_cpu for_device unmap TO_DEV writeback none writeback none TO_CPU invalidate invalidate* invalidate invalidate* BIDIR writeback invalidate writeback invalidate Signed-off-by: Guo Ren <ren_guo@xxxxxxxxx> --- arch/csky/mm/dma-mapping.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/csky/mm/dma-mapping.c b/arch/csky/mm/dma-mapping.c index 16c2087..30a2041 100644 --- a/arch/csky/mm/dma-mapping.c +++ b/arch/csky/mm/dma-mapping.c @@ -217,7 +217,8 @@ void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr, break; case DMA_FROM_DEVICE: case DMA_BIDIRECTIONAL: - BUG(); + dma_wbinv_range(vaddr + offset, vaddr + offset + size); + break; default: BUG(); } @@ -240,7 +241,7 @@ void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr, switch (dir) { case DMA_TO_DEVICE: - BUG(); + break; case DMA_FROM_DEVICE: case DMA_BIDIRECTIONAL: dma_wbinv_range(vaddr + offset, vaddr + offset + size); -- 2.7.4