Re: [PATCH 16/18] drm/vc4: Use phys addresses for slave DMA config

Frank Li
2024-06-05T18:28:55Z

On Fri, May 24, 2024 at 07:27:00PM +0100, Dave Stevenson wrote:
> From: Phil Elwell <phil@raspberrypi.com>
>
> Slave addresses for DMA are meant to be supplied as physical addresses
> (contrary to what struct snd_dmaengine_dai_dma_data does).

Can you use the same content for patch 14-17?

Frank

>
> Signed-off-by: Phil Elwell <phil@raspberrypi.com>
> Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> ---
> drivers/gpu/drm/vc4/vc4_hdmi.c | 15 ++++-----------
> 1 file changed, 4 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
> index d30f8e8e8967..c2afd72bd96e 100644
> --- a/drivers/gpu/drm/vc4/vc4_hdmi.c
> +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
> @@ -2696,7 +2696,7 @@ static int vc4_hdmi_audio_init(struct vc4_hdmi *vc4_hdmi)
> struct snd_soc_card *card = &vc4_hdmi->audio.card;
> struct device *dev = &vc4_hdmi->pdev->dev;
> struct platform_device *codec_pdev;
> - const __be32 *addr;
> + struct resource *iomem;
> int index, len;
> int ret;
>
> @@ -2732,22 +2732,15 @@ static int vc4_hdmi_audio_init(struct vc4_hdmi *vc4_hdmi)
> }
>
> /*
> - * Get the physical address of VC4_HD_MAI_DATA. We need to retrieve
> - * the bus address specified in the DT, because the physical address
> - * (the one returned by platform_get_resource()) is not appropriate
> - * for DMA transfers.
> - * This VC/MMU should probably be exposed to avoid this kind of hacks.
> + * Get the physical address of VC4_HD_MAI_DATA.
> */
> index = of_property_match_string(dev->of_node, "reg-names", "hd");
> /* Before BCM2711, we don't have a named register range */
> if (index < 0)
> index = 1;
> + iomem = platform_get_resource(vc4_hdmi->pdev, IORESOURCE_MEM, index);
>
> - addr = of_get_address(dev->of_node, index, NULL, NULL);
> - if (!addr)
> - return -EINVAL;
> -
> - vc4_hdmi->audio.dma_data.addr = be32_to_cpup(addr) + mai_data->offset;
> + vc4_hdmi->audio.dma_data.addr = iomem->start + mai_data->offset;
> vc4_hdmi->audio.dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
> vc4_hdmi->audio.dma_data.maxburst = 2;
>
> --
> 2.34.1
>