[PATCH v2 2/2] dma/imx-sdma: add wmb before enable a channel

[Richard Zhao]

dma_alloc_coherent memory may be bufferable. We need to add
nececcary memory barrier.

Signed-off-by: Richard Zhao <richard.zhao at linaro.org>
---
 drivers/dma/imx-sdma.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index f8e87b5..9301bff 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -394,6 +394,7 @@ static int sdma_config_ownership(struct sdma_channel *sdmac,
 
 static void sdma_enable_channel(struct sdma_engine *sdma, int channel)
 {
+	wmb();
 	__raw_writel(1 << channel, sdma->regs + SDMA_H_START);
 }
 
-- 
1.7.4.1