Re: [Intel-gfx] [PATCH 3/4] drm/i915/dp_mst: Use helpers to get dsc min/max input bpc

[Jani Nikula <jani.nikula@intel.com>]

On Mon, 27 Nov 2023, Ankit Nautiyal <ankit.k.nautiyal@intel.com> wrote:
> Use helpers for source min/max input bpc with DSC.
> While at it, make them return int instead of u8.
>
> v2: Make the helpers return int instead of u8. (Jani)
>
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> Reviewed-by: Suraj Kandpal <suraj.kandpal@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c     |  6 ++----
>  drivers/gpu/drm/i915/display/intel_dp.h     |  2 ++
>  drivers/gpu/drm/i915/display/intel_dp_mst.c | 11 ++++-------
>  3 files changed, 8 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index 1f68d4819282..74000b65829e 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -1622,8 +1622,7 @@ intel_dp_compute_link_config_wide(struct intel_dp *intel_dp,
>  	return -EINVAL;
>  }
>  
> -static
> -u8 intel_dp_dsc_max_src_input_bpc(struct drm_i915_private *i915)
> +int intel_dp_dsc_max_src_input_bpc(struct drm_i915_private *i915)
>  {
>  	if (!HAS_DSC(i915))
>  		return 0;
> @@ -2022,8 +2021,7 @@ static int dsc_compute_compressed_bpp(struct intel_dp *intel_dp,
>  					   dsc_max_bpp, dsc_min_bpp, pipe_bpp, timeslots);
>  }
>  
> -static
> -u8 intel_dp_dsc_min_src_input_bpc(struct drm_i915_private *i915)
> +int intel_dp_dsc_min_src_input_bpc(struct drm_i915_private *i915)
>  {
>  	/* Min DSC Input BPC for ICL+ is 8 */
>  	return HAS_DSC(i915) ? 8 : 0;
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h
> index 05db46b111f2..f613ced9eda6 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.h
> +++ b/drivers/gpu/drm/i915/display/intel_dp.h
> @@ -184,5 +184,7 @@ intel_dp_compute_config_link_bpp_limits(struct intel_dp *intel_dp,
>  					struct link_config_limits *limits);
>  
>  void intel_dp_get_dsc_sink_cap(u8 dpcd_rev, struct intel_connector *connector);
> +int intel_dp_dsc_max_src_input_bpc(struct drm_i915_private *i915);
> +int intel_dp_dsc_min_src_input_bpc(struct drm_i915_private *i915);
>  
>  #endif /* __INTEL_DP_H__ */
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index 63364c9602ef..01e9d6fb9548 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -293,17 +293,14 @@ static int intel_dp_dsc_mst_compute_link_config(struct intel_encoder *encoder,
>  	int i, num_bpc;
>  	u8 dsc_bpc[3] = {};
>  	int min_bpp, max_bpp, sink_min_bpp, sink_max_bpp;
> -	u8 dsc_max_bpc;
> +	u8 dsc_max_bpc, dsc_min_bpc;
>  	int min_compressed_bpp, max_compressed_bpp;
>  
> -	/* Max DSC Input BPC for ICL is 10 and for TGL+ is 12 */
> -	if (DISPLAY_VER(i915) >= 12)
> -		dsc_max_bpc = min_t(u8, 12, conn_state->max_requested_bpc);
> -	else
> -		dsc_max_bpc = min_t(u8, 10, conn_state->max_requested_bpc);
> +	dsc_max_bpc = intel_dp_dsc_max_src_input_bpc(i915);
> +	dsc_min_bpc = intel_dp_dsc_min_src_input_bpc(i915);
>  
>  	max_bpp = min_t(u8, dsc_max_bpc * 3, limits->pipe.max_bpp);
> -	min_bpp = limits->pipe.min_bpp;
> +	min_bpp = max_t(u8, dsc_min_bpc * 3, limits->pipe.min_bpp);

I thought it would be obvious you'd also need to change these to ints
and drop the forced u8 etc.

BR,
Jani.

>  
>  	num_bpc = drm_dp_dsc_sink_supported_input_bpcs(connector->dp.dsc_dpcd,
>  						       dsc_bpc);

-- 
Jani Nikula, Intel