openrisc does all the required cache maintainance at dma map time, and none at unmap time. It thus has to implement sync_single_for_device to match the map cace for buffer reuse, but there is no point in doing another invalidation in the sync_single_cpu_case, which in terms of cache maintainance is equivalent to the unmap case. Signed-off-by: Christoph Hellwig <hch@xxxxxx> --- arch/openrisc/kernel/dma.c | 15 --------------- 1 file changed, 15 deletions(-) diff --git a/arch/openrisc/kernel/dma.c b/arch/openrisc/kernel/dma.c index ec7fd45704d2..47601274abf7 100644 --- a/arch/openrisc/kernel/dma.c +++ b/arch/openrisc/kernel/dma.c @@ -208,20 +208,6 @@ or1k_unmap_sg(struct device *dev, struct scatterlist *sg, } } -static void -or1k_sync_single_for_cpu(struct device *dev, - dma_addr_t dma_handle, size_t size, - enum dma_data_direction dir) -{ - unsigned long cl; - dma_addr_t addr = dma_handle; - struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[smp_processor_id()]; - - /* Invalidate the dcache for the requested range */ - for (cl = addr; cl < addr + size; cl += cpuinfo->dcache_block_size) - mtspr(SPR_DCBIR, cl); -} - static void or1k_sync_single_for_device(struct device *dev, dma_addr_t dma_handle, size_t size, @@ -243,7 +229,6 @@ const struct dma_map_ops or1k_dma_map_ops = { .unmap_page = or1k_unmap_page, .map_sg = or1k_map_sg, .unmap_sg = or1k_unmap_sg, - .sync_single_for_cpu = or1k_sync_single_for_cpu, .sync_single_for_device = or1k_sync_single_for_device, }; EXPORT_SYMBOL(or1k_dma_map_ops); -- 2.17.0