Hi Laurent,
Thanks for the patch:
On 17/05/17 00:20, Laurent Pinchart wrote:
> From: Magnus Damm <magnus.d...@gmail.com>
>
> On Gen2 hardware the VSP1 is a bus master and accesses the display list
> and video buffers through DMA directly. On Gen3 hardware, however,
> memory accesses go through a separate IP core called FCP.
>
> The VSP1 driver unconditionally maps DMA buffers through the VSP device.
> While this doesn't cause any practical issue so far, DMA mappings will
> be incorrect as soon as we will enable IOMMU support for the FCP on Gen3
> platforms, resulting in IOMMU faults.
>
> Fix this by mapping all buffers through the FCP device if present, and
> through the VSP1 device as usual otherwise.
>
> Suggested-by: Magnus Damm <magnus.d...@gmail.com>
> [Cache the bus master device]
> Signed-off-by: Laurent Pinchart <laurent.pinchart+rene...@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham+rene...@ideasonboard.com>
> ---
> drivers/media/platform/vsp1/vsp1.h | 1 +
> drivers/media/platform/vsp1/vsp1_dl.c | 4 ++--
> drivers/media/platform/vsp1/vsp1_drv.c | 9 +++++++++
> drivers/media/platform/vsp1/vsp1_video.c | 2 +-
> 4 files changed, 13 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/media/platform/vsp1/vsp1.h
> b/drivers/media/platform/vsp1/vsp1.h
> index 85387a64179a..847963b6e9eb 100644
> --- a/drivers/media/platform/vsp1/vsp1.h
> +++ b/drivers/media/platform/vsp1/vsp1.h
> @@ -74,6 +74,7 @@ struct vsp1_device {
>
> void __iomem *mmio;
> struct rcar_fcp_device *fcp;
> + struct device *bus_master;
>
> struct vsp1_bru *bru;
> struct vsp1_clu *clu;
> diff --git a/drivers/media/platform/vsp1/vsp1_dl.c
> b/drivers/media/platform/vsp1/vsp1_dl.c
> index 7d8f37772b56..445d1c31fff3 100644
> --- a/drivers/media/platform/vsp1/vsp1_dl.c
> +++ b/drivers/media/platform/vsp1/vsp1_dl.c
> @@ -137,7 +137,7 @@ static int vsp1_dl_body_init(struct vsp1_device *vsp1,
> dlb->vsp1 = vsp1;
> dlb->size = size;
>
> - dlb->entries = dma_alloc_wc(vsp1->dev, dlb->size, &dlb->dma,
> + dlb->entries = dma_alloc_wc(vsp1->bus_master, dlb->size, &dlb->dma,
> GFP_KERNEL);
> if (!dlb->entries)
> return -ENOMEM;
> @@ -150,7 +150,7 @@ static int vsp1_dl_body_init(struct vsp1_device *vsp1,
> */
> static void vsp1_dl_body_cleanup(struct vsp1_dl_body *dlb)
> {
> - dma_free_wc(dlb->vsp1->dev, dlb->size, dlb->entries, dlb->dma);
> + dma_free_wc(dlb->vsp1->bus_master, dlb->size, dlb->entries, dlb->dma);
> }
>
> /**
> diff --git a/drivers/media/platform/vsp1/vsp1_drv.c
> b/drivers/media/platform/vsp1/vsp1_drv.c
> index 048446af5ae7..95c26edead85 100644
> --- a/drivers/media/platform/vsp1/vsp1_drv.c
> +++ b/drivers/media/platform/vsp1/vsp1_drv.c
> @@ -764,6 +764,15 @@ static int vsp1_probe(struct platform_device *pdev)
> PTR_ERR(vsp1->fcp));
> return PTR_ERR(vsp1->fcp);
> }
> +
> + /*
> + * When the FCP is present, it handles all bus master accesses
> + * for the VSP and must thus be used in place of the VSP device
> + * to map DMA buffers.
> + */
> + vsp1->bus_master = rcar_fcp_get_device(vsp1->fcp);
> + } else {
> + vsp1->bus_master = vsp1->dev;
> }
>
> /* Configure device parameters based on the version register. */
> diff --git a/drivers/media/platform/vsp1/vsp1_video.c
> b/drivers/media/platform/vsp1/vsp1_video.c
> index eab3c3ea85d7..5af3486afe07 100644
> --- a/drivers/media/platform/vsp1/vsp1_video.c
> +++ b/drivers/media/platform/vsp1/vsp1_video.c
> @@ -1197,7 +1197,7 @@ struct vsp1_video *vsp1_video_create(struct vsp1_device
> *vsp1,
> video->queue.ops = &vsp1_video_queue_qops;
> video->queue.mem_ops = &vb2_dma_contig_memops;
> video->queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
> - video->queue.dev = video->vsp1->dev;
> + video->queue.dev = video->vsp1->bus_master;
> ret = vb2_queue_init(&video->queue);
> if (ret < 0) {
> dev_err(video->vsp1->dev, "failed to initialize vb2 queue\n");
>
