Re: [PATCH 26/50] drm/i915/dp: Factor out compute_max_compressed_bpp_x16()

["Govindapillai, Vinod" <vinod.govindapillai@intel.com>]

On Thu, 2025-11-27 at 19:49 +0200, Imre Deak wrote:
> Factor out compute_max_compressed_bpp_x16() also used during mode
> validation in a follow-up change.
> 
> Signed-off-by: Imre Deak <imre.deak@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c | 82 +++++++++++++++--------
> --
>  1 file changed, 49 insertions(+), 33 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> b/drivers/gpu/drm/i915/display/intel_dp.c
> index 2a5f5f1b4b128..9deb99eda8813 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -2662,6 +2662,48 @@ static int
> compute_min_compressed_bpp_x16(struct intel_connector *connector,
>  	return min_bpp_x16;
>  }
>  
> +static int compute_max_compressed_bpp_x16(struct intel_connector
> *connector,

const ?

Reviewed-by: Vinod Govindapillai <vinod.govindapillai@intel.com>

> +					  int mode_clock, int
> mode_hdisplay,
> +					  int num_joined_pipes,
> +					  enum intel_output_format
> output_format,
> +					  int pipe_max_bpp, int
> max_link_bpp_x16)
> +{
> +	struct intel_display *display = to_intel_display(connector);
> +	struct intel_dp *intel_dp = intel_attached_dp(connector);
> +	int dsc_src_max_bpp, dsc_sink_max_bpp, dsc_max_bpp;
> +	int throughput_max_bpp_x16;
> +	int joiner_max_bpp;
> +
> +	dsc_src_max_bpp = dsc_src_max_compressed_bpp(intel_dp);
> +	joiner_max_bpp = get_max_compressed_bpp_with_joiner(display,
> +							   
> mode_clock,
> +							   
> mode_hdisplay,
> +							   
> num_joined_pipes);
> +	dsc_sink_max_bpp =
> intel_dp_dsc_sink_max_compressed_bpp(connector,
> +								outp
> ut_format,
> +								pipe
> _max_bpp / 3);
> +	dsc_max_bpp = min(dsc_sink_max_bpp, dsc_src_max_bpp);
> +	dsc_max_bpp = min(dsc_max_bpp, joiner_max_bpp);
> +
> +	max_link_bpp_x16 = min(max_link_bpp_x16,
> fxp_q4_from_int(dsc_max_bpp));
> +
> +	throughput_max_bpp_x16 =
> dsc_throughput_quirk_max_bpp_x16(connector,
> +								 
> mode_clock);
> +	if (throughput_max_bpp_x16 < max_link_bpp_x16) {
> +		max_link_bpp_x16 = throughput_max_bpp_x16;
> +
> +		drm_dbg_kms(display->drm,
> +			    "[CONNECTOR:%d:%s] Decreasing link max
> bpp to " FXP_Q4_FMT " due to DSC throughput quirk\n",
> +			    connector->base.base.id, connector-
> >base.name,
> +			    FXP_Q4_ARGS(max_link_bpp_x16));
> +	}
> +
> +	max_link_bpp_x16 = align_max_compressed_bpp_x16(connector,
> output_format,
> +							pipe_max_bpp
> , max_link_bpp_x16);
> +
> +	return max_link_bpp_x16;
> +}
> +
>  /*
>   * Calculate the output link min, max bpp values in limits based on
> the pipe bpp
>   * range, crtc_state and dsc mode. Return true on success.
> @@ -2691,43 +2733,17 @@
> intel_dp_compute_config_link_bpp_limits(struct intel_connector
> *connector,
>  
>  		limits->link.min_bpp_x16 = fxp_q4_from_int(limits-
> >pipe.min_bpp);
>  	} else {
> -		int dsc_src_max_bpp, dsc_sink_max_bpp, dsc_max_bpp;
> -		int throughput_max_bpp_x16;
> -		int joiner_max_bpp;
>  		limits->link.min_bpp_x16 =
>  			compute_min_compressed_bpp_x16(connector,
> crtc_state->output_format);
>  
> -		dsc_src_max_bpp =
> dsc_src_max_compressed_bpp(intel_dp);
> -		joiner_max_bpp =
> -			get_max_compressed_bpp_with_joiner(display,
> -							  
> adjusted_mode->crtc_clock,
> -							  
> adjusted_mode->hdisplay,
> -							  
> intel_crtc_num_joined_pipes(crtc_state));
> -		dsc_sink_max_bpp =
> intel_dp_dsc_sink_max_compressed_bpp(connector,
> -
> 									crtc_state->output_format,
> -
> 									limits->pipe.max_bpp / 3);
> -		dsc_max_bpp = min(dsc_sink_max_bpp,
> dsc_src_max_bpp);
> -		dsc_max_bpp = min(dsc_max_bpp, joiner_max_bpp);
> -
> -		max_link_bpp_x16 = min(max_link_bpp_x16,
> fxp_q4_from_int(dsc_max_bpp));
> -
> -		throughput_max_bpp_x16 =
> -			dsc_throughput_quirk_max_bpp_x16(connector,
> adjusted_mode->crtc_clock);
> -		if (throughput_max_bpp_x16 < max_link_bpp_x16) {
> -			max_link_bpp_x16 = throughput_max_bpp_x16;
> -
> -			drm_dbg_kms(display->drm,
> -				    "[CRTC:%d:%s][CONNECTOR:%d:%s]
> Decreasing link max bpp to " FXP_Q4_FMT " due to DSC throughput
> quirk\n",
> -				    crtc->base.base.id, crtc-
> >base.name,
> -				    connector->base.base.id,
> connector->base.name,
> -				    FXP_Q4_ARGS(max_link_bpp_x16));
> -		}
> -
>  		max_link_bpp_x16 =
> -			align_max_compressed_bpp_x16(connector,
> -						     crtc_state-
> >output_format,
> -						     limits-
> >pipe.max_bpp,
> -						    
> max_link_bpp_x16);
> +			compute_max_compressed_bpp_x16(connector,
> +						      
> adjusted_mode->crtc_clock,
> +						      
> adjusted_mode->hdisplay,
> +						      
> intel_crtc_num_joined_pipes(crtc_state),
> +						       crtc_state-
> >output_format,
> +						       limits-
> >pipe.max_bpp,
> +						      
> max_link_bpp_x16);
>  	}
>  
>  	limits->link.max_bpp_x16 = max_link_bpp_x16;