From: Nikhil Devshatwar <nikhil...@ti.com>
VPDMA buffer will be used by CPU as well as by the VPDMA.
CPU will write/update the VPDMA descriptors containing data
about the video buffer DMA addresses.
VPDMA will write the "write descriptor" containing the
data about the DMA operation.
When mapping/unmapping the buffer, driver has to take care of
WriteBack and invalidation of the cache so that all the
coherency is maintained from both directions.
Use DMA_BIDIRECTIONAL to maintain coherency between CPU and VPDMA.
Signed-off-by: Nikhil Devshatwar <nikhil...@ti.com>
Signed-off-by: Benoit Parrot <bpar...@ti.com>
Acked-by: Hans Verkuil <hans.verk...@cisco.com>
---
drivers/media/platform/ti-vpe/vpdma.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/media/platform/ti-vpe/vpdma.c
b/drivers/media/platform/ti-vpe/vpdma.c
index 070937fe1af6..2d13644a28a8 100644
--- a/drivers/media/platform/ti-vpe/vpdma.c
+++ b/drivers/media/platform/ti-vpe/vpdma.c
@@ -367,7 +367,7 @@ int vpdma_map_desc_buf(struct vpdma_data *vpdma, struct
vpdma_buf *buf)
WARN_ON(buf->mapped);
buf->dma_addr = dma_map_single(dev, buf->addr, buf->size,
- DMA_TO_DEVICE);
+ DMA_BIDIRECTIONAL);
if (dma_mapping_error(dev, buf->dma_addr)) {
dev_err(dev, "failed to map buffer\n");
return -EINVAL;
@@ -388,7 +388,8 @@ void vpdma_unmap_desc_buf(struct vpdma_data *vpdma, struct
vpdma_buf *buf)
struct device *dev = &vpdma->pdev->dev;
if (buf->mapped)
- dma_unmap_single(dev, buf->dma_addr, buf->size, DMA_TO_DEVICE);
+ dma_unmap_single(dev, buf->dma_addr, buf->size,
+ DMA_BIDIRECTIONAL);
buf->mapped = false;
}
--
2.9.0
--
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