Re: [PATCH v4 39/39] drm/msm/dp: Add MST stream support for supported DP controllers

[Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>]

On Fri, Apr 10, 2026 at 05:34:14PM +0800, Yongxing Mou wrote:
> Enables MST support for MSM DP controllers that support it, allowing each
> controller to handle up to two or four DisplayPort streams. All necessary
> MST support code was already implemented in the previous series of patches.

As I wrote earlier, we have this information in the DT. Please drop.

> 
> Signed-off-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com>
> ---
>  drivers/gpu/drm/msm/dp/dp_display.c | 42 ++++++++++++++++++++++++-------------
>  1 file changed, 28 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
> index ca89e20b7563..f632b4f64ccc 100644
> --- a/drivers/gpu/drm/msm/dp/dp_display.c
> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
> @@ -107,16 +107,21 @@ struct msm_dp_desc {
>  };
>  
>  static const struct msm_dp_desc msm_dp_desc_glymur[] = {
> -	{ .io_start = 0x0af54000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true },
> -	{ .io_start = 0x0af5c000, .id = MSM_DP_CONTROLLER_1, .wide_bus_supported = true },
> -	{ .io_start = 0x0af64000, .id = MSM_DP_CONTROLLER_2, .wide_bus_supported = true },
> +	{ .io_start = 0x0af54000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true,
> +	  .mst_streams = 2 },
> +	{ .io_start = 0x0af5c000, .id = MSM_DP_CONTROLLER_1, .wide_bus_supported = true,
> +	  .mst_streams = 2 },
> +	{ .io_start = 0x0af64000, .id = MSM_DP_CONTROLLER_2, .wide_bus_supported = true,
> +	  .mst_streams = 2 },
>  	{ .io_start = 0x0af6c000, .id = MSM_DP_CONTROLLER_3, .wide_bus_supported = true },
>  	{}
>  };
>  
>  static const struct msm_dp_desc msm_dp_desc_sa8775p[] = {
> -	{ .io_start = 0x0af54000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true },
> -	{ .io_start = 0x0af5c000, .id = MSM_DP_CONTROLLER_1, .wide_bus_supported = true },
> +	{ .io_start = 0x0af54000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true,
> +	  .mst_streams = 4},
> +	{ .io_start = 0x0af5c000, .id = MSM_DP_CONTROLLER_1, .wide_bus_supported = true,
> +	  .mst_streams = 2},
>  	{ .io_start = 0x22154000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true },
>  	{ .io_start = 0x2215c000, .id = MSM_DP_CONTROLLER_1, .wide_bus_supported = true },
>  	{}
> @@ -133,38 +138,47 @@ static const struct msm_dp_desc msm_dp_desc_sc7180[] = {
>  };
>  
>  static const struct msm_dp_desc msm_dp_desc_sc7280[] = {
> -	{ .io_start = 0x0ae90000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true },
> +	{ .io_start = 0x0ae90000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true,
> +	  .mst_streams = 2 },
>  	{ .io_start = 0x0aea0000, .id = MSM_DP_CONTROLLER_1, .wide_bus_supported = true },
>  	{}
>  };
>  
>  static const struct msm_dp_desc msm_dp_desc_sc8180x[] = {
> -	{ .io_start = 0x0ae90000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true },
> +	{ .io_start = 0x0ae90000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true,
> +	  .mst_streams = 2 },
>  	{ .io_start = 0x0ae98000, .id = MSM_DP_CONTROLLER_1, .wide_bus_supported = true },
>  	{ .io_start = 0x0ae9a000, .id = MSM_DP_CONTROLLER_2, .wide_bus_supported = true },
>  	{}
>  };
>  
>  static const struct msm_dp_desc msm_dp_desc_sc8280xp[] = {
> -	{ .io_start = 0x0ae90000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true },
> -	{ .io_start = 0x0ae98000, .id = MSM_DP_CONTROLLER_1, .wide_bus_supported = true },
> +	{ .io_start = 0x0ae90000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true,
> +	  .mst_streams = 2},
> +	{ .io_start = 0x0ae98000, .id = MSM_DP_CONTROLLER_1, .wide_bus_supported = true,
> +	  .mst_streams = 2},
>  	{ .io_start = 0x0ae9a000, .id = MSM_DP_CONTROLLER_2, .wide_bus_supported = true },
>  	{ .io_start = 0x0aea0000, .id = MSM_DP_CONTROLLER_3, .wide_bus_supported = true },
> -	{ .io_start = 0x22090000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true },
> -	{ .io_start = 0x22098000, .id = MSM_DP_CONTROLLER_1, .wide_bus_supported = true },
> +	{ .io_start = 0x22090000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true,
> +	  .mst_streams = 2},
> +	{ .io_start = 0x22098000, .id = MSM_DP_CONTROLLER_1, .wide_bus_supported = true,
> +	  .mst_streams = 2},
>  	{ .io_start = 0x2209a000, .id = MSM_DP_CONTROLLER_2, .wide_bus_supported = true },
>  	{ .io_start = 0x220a0000, .id = MSM_DP_CONTROLLER_3, .wide_bus_supported = true },
>  	{}
>  };
>  
>  static const struct msm_dp_desc msm_dp_desc_sm8650[] = {
> -	{ .io_start = 0x0af54000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true },
> +	{ .io_start = 0x0af54000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true,
> +	  .mst_streams = 2 },
>  	{}
>  };
>  
>  static const struct msm_dp_desc msm_dp_desc_x1e80100[] = {
> -	{ .io_start = 0x0ae90000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true },
> -	{ .io_start = 0x0ae98000, .id = MSM_DP_CONTROLLER_1, .wide_bus_supported = true },
> +	{ .io_start = 0x0ae90000, .id = MSM_DP_CONTROLLER_0, .wide_bus_supported = true,
> +	  .mst_streams = 2},
> +	{ .io_start = 0x0ae98000, .id = MSM_DP_CONTROLLER_1, .wide_bus_supported = true,
> +	  .mst_streams = 2},
>  	{ .io_start = 0x0ae9a000, .id = MSM_DP_CONTROLLER_2, .wide_bus_supported = true },
>  	{ .io_start = 0x0aea0000, .id = MSM_DP_CONTROLLER_3, .wide_bus_supported = true },
>  	{}
> 
> -- 
> 2.43.0
> 

-- 
With best wishes
Dmitry