dma-mapping: turn dma_cache_sync into a dma_map_ops method

After we removed all the dead wood it turns out only two architectures
actually implement dma_cache_sync as a real op: mips and parisc.  Add
a cache_sync method to struct dma_map_ops and implement it for the
mips defualt DMA ops, and the parisc pa11 ops.

Note that arm, arc and openrisc support DMA_ATTR_NON_CONSISTENT, but
never provided a functional dma_cache_sync implementations, which
seems somewhat odd.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>

1 files changed, 0 insertions, 9 deletions

diff --git a/arch/nios2/include/asm/dma-mapping.h b/arch/nios2/include/asm/dma-mapping.h
index f8dc622..6ceb922 100644
--- a/arch/nios2/include/asm/dma-mapping.h
+++ b/arch/nios2/include/asm/dma-mapping.h
@@ -17,13 +17,4 @@ static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
 	return &nios2_dma_ops;
 }
 
-/*
- * dma_alloc_attrs() always returns non-cacheable memory, so there's no need to
- * do any flushing here.
- */
-static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
-				  enum dma_data_direction direction)
-{
-}
-
 #endif /* _ASM_NIOS2_DMA_MAPPING_H */