[PATCH 08/11] unicore32: make dma_cache_sync a no-op

From: Christoph Hellwig
Date: Tue Oct 03 2017 - 06:45:27 EST


unicore32 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.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
arch/unicore32/include/asm/cacheflush.h | 9 ---------
arch/unicore32/include/asm/dma-mapping.h | 17 -----------------
arch/unicore32/mm/proc-syms.c | 3 ---
3 files changed, 29 deletions(-)

diff --git a/arch/unicore32/include/asm/cacheflush.h b/arch/unicore32/include/asm/cacheflush.h
index c0301e6c8b81..a5e08e2d5d6d 100644
--- a/arch/unicore32/include/asm/cacheflush.h
+++ b/arch/unicore32/include/asm/cacheflush.h
@@ -101,15 +101,6 @@ extern void __cpuc_coherent_user_range(unsigned long, unsigned long);
extern void __cpuc_flush_dcache_area(void *, size_t);
extern void __cpuc_flush_kern_dcache_area(void *addr, size_t size);

-/*
- * These are private to the dma-mapping API. Do not use directly.
- * Their sole purpose is to ensure that data held in the cache
- * is visible to DMA, or data written by DMA to system memory is
- * visible to the CPU.
- */
-extern void __cpuc_dma_clean_range(unsigned long, unsigned long);
-extern void __cpuc_dma_flush_range(unsigned long, unsigned long);
-
/*
* Copy user data from/to a page which is mapped into a different
* processes address space. Really, we want to allow our "user
diff --git a/arch/unicore32/include/asm/dma-mapping.h b/arch/unicore32/include/asm/dma-mapping.h
index 518ba5848dd6..e949855bb794 100644
--- a/arch/unicore32/include/asm/dma-mapping.h
+++ b/arch/unicore32/include/asm/dma-mapping.h
@@ -18,9 +18,6 @@
#include <linux/scatterlist.h>
#include <linux/swiotlb.h>

-#include <asm/memory.h>
-#include <asm/cacheflush.h>
-
extern const struct dma_map_ops swiotlb_dma_map_ops;

static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
@@ -51,20 +48,6 @@ static inline void dma_mark_clean(void *addr, size_t size) {}
static inline void dma_cache_sync(struct device *dev, void *vaddr,
size_t size, enum dma_data_direction direction)
{
- unsigned long start = (unsigned long)vaddr;
- unsigned long end = start + size;
-
- switch (direction) {
- case DMA_NONE:
- BUG();
- case DMA_FROM_DEVICE:
- case DMA_BIDIRECTIONAL: /* writeback and invalidate */
- __cpuc_dma_flush_range(start, end);
- break;
- case DMA_TO_DEVICE: /* writeback only */
- __cpuc_dma_clean_range(start, end);
- break;
- }
}

#endif /* __KERNEL__ */
diff --git a/arch/unicore32/mm/proc-syms.c b/arch/unicore32/mm/proc-syms.c
index 21c00fc85c99..df215fd6d639 100644
--- a/arch/unicore32/mm/proc-syms.c
+++ b/arch/unicore32/mm/proc-syms.c
@@ -20,6 +20,3 @@ EXPORT_SYMBOL(cpu_dcache_clean_area);
EXPORT_SYMBOL(cpu_set_pte);

EXPORT_SYMBOL(__cpuc_coherent_kern_range);
-
-EXPORT_SYMBOL(__cpuc_dma_flush_range);
-EXPORT_SYMBOL(__cpuc_dma_clean_range);
--
2.14.1