microblaze: make dma_cache_sync a no-op

microblaze does not implement DMA_ATTR_NON_CONSISTENT allocations, so it
doesn't make any sense to do any work in dma_cache_sync given that it
must be a no-op when dma_alloc_attrs returns coherent memory.

This also allows moving __dma_sync out of the microblaze asm/dma-mapping.h
and thus greatly reduce the amount of includes there.

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

2 files changed, 17 insertions, 34 deletions

diff --git a/arch/microblaze/include/asm/dma-mapping.h b/arch/microblaze/include/asm/dma-mapping.h
index e15cd2f76e23..ad448e4aedb6 100644
--- a/arch/microblaze/include/asm/dma-mapping.h
+++ b/arch/microblaze/include/asm/dma-mapping.h
@@ -16,22 +16,6 @@
 #define _ASM_MICROBLAZE_DMA_MAPPING_H
 
 /*
- * See Documentation/DMA-API-HOWTO.txt and
- * Documentation/DMA-API.txt for documentation.
- */
-
-#include <linux/types.h>
-#include <linux/cache.h>
-#include <linux/mm.h>
-#include <linux/scatterlist.h>
-#include <linux/dma-debug.h>
-#include <asm/io.h>
-#include <asm/cacheflush.h>
-
-#define __dma_alloc_coherent(dev, gfp, size, handle)    NULL
-#define __dma_free_coherent(size, addr)         ((void)0)
-
-/*
  * Available generic sets of operations
  */
 extern const struct dma_map_ops dma_direct_ops;
@@ -41,27 +25,9 @@ static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
         return &dma_direct_ops;
 }
 
-static inline void __dma_sync(unsigned long paddr,
-                              size_t size, enum dma_data_direction direction)
-{
-        switch (direction) {
-        case DMA_TO_DEVICE:
-        case DMA_BIDIRECTIONAL:
-                flush_dcache_range(paddr, paddr + size);
-                break;
-        case DMA_FROM_DEVICE:
-                invalidate_dcache_range(paddr, paddr + size);
-                break;
-        default:
-                BUG();
-        }
-}
-
 static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
                 enum dma_data_direction direction)
 {
-        BUG_ON(direction == DMA_NONE);
-        __dma_sync(virt_to_phys(vaddr), size, (int)direction);
 }
 
 #endif  /* _ASM_MICROBLAZE_DMA_MAPPING_H */
diff --git a/arch/microblaze/kernel/dma.c b/arch/microblaze/kernel/dma.c
index 94700c5270a9..e52b684f8ea2 100644
--- a/arch/microblaze/kernel/dma.c
+++ b/arch/microblaze/kernel/dma.c
@@ -12,6 +12,7 @@
 #include <linux/dma-debug.h>
 #include <linux/export.h>
 #include <linux/bug.h>
+#include <asm/cacheflush.h>
 
 #define NOT_COHERENT_CACHE
 
@@ -51,6 +52,22 @@ static void dma_direct_free_coherent(struct device *dev, size_t size,
 #endif
 }
 
+static inline void __dma_sync(unsigned long paddr,
+                              size_t size, enum dma_data_direction direction)
+{
+        switch (direction) {
+        case DMA_TO_DEVICE:
+        case DMA_BIDIRECTIONAL:
+                flush_dcache_range(paddr, paddr + size);
+                break;
+        case DMA_FROM_DEVICE:
+                invalidate_dcache_range(paddr, paddr + size);
+                break;
+        default:
+                BUG();
+        }
+}
+
 static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
                              int nents, enum dma_data_direction direction,
                              unsigned long attrs)