[PATCH 2/3] define ARM-specific dma_coherent_write_sync

Mark Salter msalter at redhat.com
Wed Aug 31 17:30:13 EDT 2011


For ARM kernels using CONFIG_ARM_DMA_MEM_BUFFERABLE, this patch adds an ARM
specific dma_coherent_write_sync() to override the default version. This
routine forces out any data sitting in a write buffer between the CPU and
memory.

Signed-off-by: Mark Salter <msalter at redhat.com>
---
 arch/arm/include/asm/dma-mapping.h |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h
index 7a21d0b..e99562b 100644
--- a/arch/arm/include/asm/dma-mapping.h
+++ b/arch/arm/include/asm/dma-mapping.h
@@ -206,6 +206,16 @@ int dma_mmap_writecombine(struct device *, struct vm_area_struct *,
 		void *, dma_addr_t, size_t);
 
 
+#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
+#define ARCH_HAS_DMA_COHERENT_WRITE_SYNC
+
+static inline void dma_coherent_write_sync(void)
+{
+	dsb();
+	outer_sync();
+}
+#endif
+
 #ifdef CONFIG_DMABOUNCE
 /*
  * For SA-1111, IXP425, and ADI systems  the dma-mapping functions are "magic"
-- 
1.7.6




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