[Intel-gfx] [PATCH v6 2/2] drm/i915/display/dsc: Set BPP in the kernel

[Jani Nikula]

On Mon, 05 Jul 2021, venkata.sai.patnana at intel.com wrote:
> From: Anusha Srivatsa <anusha.srivatsa at intel.com>
>
> Set compress BPP in kernel while connector DP or eDP
>
> Cc: Vandita Kulkarni <vandita.kulkarni at intel.com>
> Cc: Navare Manasi D <manasi.d.navare at intel.com>
> Signed-off-by: Anusha Srivatsa <anusha.srivatsa at intel.com>
> Signed-off-by: Patnana Venkata Sai <venkata.sai.patnana at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp.c | 27 ++++++++++++++++++-------
>  1 file changed, 20 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> index 5b52beaddada0..e756cc82a8d7d 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -1241,9 +1241,15 @@ static int intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
>  	pipe_config->lane_count = limits->max_lane_count;
>  
>  	if (intel_dp_is_edp(intel_dp)) {
> -		pipe_config->dsc.compressed_bpp =
> -			min_t(u16, drm_edp_dsc_sink_output_bpp(intel_dp->dsc_dpcd) >> 4,
> -			      pipe_config->pipe_bpp);
> +		if (intel_dp->force_dsc_bpp) {
> +			drm_dbg_kms(&dev_priv->drm,
> +				    "DSC BPP forced to %d", intel_dp->force_dsc_bpp);
> +			pipe_config->dsc.compressed_bpp = intel_dp->force_dsc_bpp;
> +		} else {
> +			pipe_config->dsc.compressed_bpp =
> +				min_t(u16, drm_edp_dsc_sink_output_bpp(intel_dp->dsc_dpcd) >> 4,
> +				      pipe_config->pipe_bpp);
> +		}
>  		pipe_config->dsc.slice_count =
>  			drm_dp_dsc_sink_max_slice_count(intel_dp->dsc_dpcd,
>  							true);
> @@ -1269,9 +1275,15 @@ static int intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
>  				    "Compressed BPP/Slice Count not supported\n");
>  			return -EINVAL;
>  		}
> -		pipe_config->dsc.compressed_bpp = min_t(u16,
> -							       dsc_max_output_bpp >> 4,
> -							       pipe_config->pipe_bpp);
> +		if (intel_dp->force_dsc_bpp) {
> +			drm_dbg_kms(&dev_priv->drm,
> +				    "DSC BPP forced to %d\n", intel_dp->force_dsc_bpp);
> +			pipe_config->dsc.compressed_bpp = intel_dp->force_dsc_bpp;
> +		} else {
> +			pipe_config->dsc.compressed_bpp = min_t(u16,
> +								dsc_max_output_bpp >> 4,
> +								pipe_config->pipe_bpp);
> +		}
>  		pipe_config->dsc.slice_count = dsc_dp_slice_count;
>  	}

AFAICT you could just move the if (intel_dp->force_dsc_bpp) here, and
overwrite pipe_config->dsc.compressed_bpp. The branches above are
already too complicated and in need of refactoring, no need to duplicate
the same code in two places there IMO.

>  	/*
> @@ -1374,7 +1386,8 @@ intel_dp_compute_link_config(struct intel_encoder *encoder,
>  	 * Pipe joiner needs compression upto display12 due to BW limitation. DG2
>  	 * onwards pipe joiner can be enabled without compression.
>  	 */
> -	drm_dbg_kms(&i915->drm, "Force DSC en = %d\n", intel_dp->force_dsc_en);
> +	drm_dbg_kms(&i915->drm, "Force DSC en = %d\n Force DSC BPP = %d\n",
> +		    intel_dp->force_dsc_en, intel_dp->force_dsc_bpp);

Unnecessary change. You already log the force DSC BPP once.

BR,
Jani.


>  	if (ret || intel_dp->force_dsc_en || (DISPLAY_VER(i915) < 13 &&
>  					      pipe_config->bigjoiner)) {
>  		ret = intel_dp_dsc_compute_config(intel_dp, pipe_config,

-- 
Jani Nikula, Intel Open Source Graphics Center