Messages in this thread Patch in this message | | | From | Benoit Parrot <> | Subject | [Patch v2 26/35] media: ti-vpe: vpdma: Use bidirectional cached buffers | Date | Fri, 18 Nov 2016 17:20:36 -0600 |
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From: Nikhil Devshatwar <nikhil.nd@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.nd@ti.com> Signed-off-by: Benoit Parrot <bparrot@ti.com> Acked-by: Hans Verkuil <hans.verkuil@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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