Re: [PATCH v7, 12/15] media: mtk-vcodec: Support 34bits dma address for vdec

AngeloGioacchino Del Regno
2021-10-14T11:02:58Z

> Use the dma_set_mask_and_coherent helper to set vdec
> DMA bit mask to support 34bits iova space(16GB) that
> the mt8192 iommu HW support.
>
> Whole the iova range separate to 0~4G/4G~8G/8G~12G/12G~16G,
> regarding which iova range VDEC actually locate, it
> depends on the dma-ranges property of vdec dtsi node.
>
> Signed-off-by: Yunfei Dong <yunfei.dong@mediatek.com>
> ---
> drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_drv.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_drv.c b/drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_drv.c
> index de83e3b821b4..da963cdac96b 100644
> --- a/drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_drv.c
> +++ b/drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_drv.c
> @@ -376,6 +376,9 @@ static int mtk_vcodec_probe(struct platform_device *pdev)
> }
> }
>
> + if (of_get_property(pdev->dev.of_node, "dma-ranges", NULL))
> + dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(34));
> +

This function returns 0 for success, or negative number for failure: please check
the return value, or this driver may not work correctly in some corner cases.

Regards,
- Angelo

> for (i = 0; i < MTK_VDEC_HW_MAX; i++)
> mutex_init(&dev->dec_mutex[i]);
> spin_lock_init(&dev->irqlock);
>