[v1] media: raspberrypi: cfe: Fix mapping of dmabuf buffers

[PATCH] media: raspberrypi: cfe: Fix mapping of dmabuf buffers

Posted by Tomi Valkeinen 3 weeks, 2 days ago

When using buffers from DRM, DMA-API gives a warning about: "mapping sg
segment longer than device claims to support [len=307200] [max=65536]"

Add a call to vb2_dma_contig_set_max_seg_size() to tell the DMA-API
about the supported segment size (which is UINT_MAX).

Fixes: 6edb685abb2a ("media: raspberrypi: Add support for RP1-CFE")
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
---
 drivers/media/platform/raspberrypi/rp1-cfe/cfe.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/media/platform/raspberrypi/rp1-cfe/cfe.c b/drivers/media/platform/raspberrypi/rp1-cfe/cfe.c
index 045910de6c57..e52d8b20df40 100644
--- a/drivers/media/platform/raspberrypi/rp1-cfe/cfe.c
+++ b/drivers/media/platform/raspberrypi/rp1-cfe/cfe.c
@@ -2341,6 +2341,12 @@ static int cfe_probe(struct platform_device *pdev)
 		goto err_cfe_put;
 	}
 
+	ret = vb2_dma_contig_set_max_seg_size(&pdev->dev, UINT_MAX);
+	if (ret) {
+		dev_err(&pdev->dev, "Unable to set max_seg_size\n");
+		goto err_cfe_put;
+	}
+
 	/* TODO: Enable clock only when running. */
 	cfe->clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(cfe->clk))

---
base-commit: 698b6e3163bafd61e1b7d13572e2c42974ac85ec
change-id: 20241101-rp1-cfe-fixes-seg-size-b70309da74a2

Best regards,
-- 
Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>

Re: [PATCH] media: raspberrypi: cfe: Fix mapping of dmabuf buffers

Posted by Laurent Pinchart 3 weeks ago

Hi Tomi,

Thank you for the patch.

On Fri, Nov 01, 2024 at 01:55:15PM +0200, Tomi Valkeinen wrote:
> When using buffers from DRM, DMA-API gives a warning about: "mapping sg
> segment longer than device claims to support [len=307200] [max=65536]"
> 
> Add a call to vb2_dma_contig_set_max_seg_size() to tell the DMA-API
> about the supported segment size (which is UINT_MAX).
> 
> Fixes: 6edb685abb2a ("media: raspberrypi: Add support for RP1-CFE")
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> ---
>  drivers/media/platform/raspberrypi/rp1-cfe/cfe.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/media/platform/raspberrypi/rp1-cfe/cfe.c b/drivers/media/platform/raspberrypi/rp1-cfe/cfe.c
> index 045910de6c57..e52d8b20df40 100644
> --- a/drivers/media/platform/raspberrypi/rp1-cfe/cfe.c
> +++ b/drivers/media/platform/raspberrypi/rp1-cfe/cfe.c
> @@ -2341,6 +2341,12 @@ static int cfe_probe(struct platform_device *pdev)
>  		goto err_cfe_put;
>  	}
>  
> +	ret = vb2_dma_contig_set_max_seg_size(&pdev->dev, UINT_MAX);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Unable to set max_seg_size\n");

Maybe dev_err_probe() ? Or drop the error message, as
vb2_dma_contig_set_max_seg_size() already prints an error.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> +		goto err_cfe_put;
> +	}
> +
>  	/* TODO: Enable clock only when running. */
>  	cfe->clk = devm_clk_get(&pdev->dev, NULL);
>  	if (IS_ERR(cfe->clk))
> 
> ---
> base-commit: 698b6e3163bafd61e1b7d13572e2c42974ac85ec
> change-id: 20241101-rp1-cfe-fixes-seg-size-b70309da74a2

-- 
Regards,

Laurent Pinchart