Re: [PATCH 37/50] drm/i915/dsc: Track the DSC stream count in the DSC slice config state

["Hogander, Jouni" <jouni.hogander@intel.com>]

On Thu, 2025-11-27 at 19:50 +0200, Imre Deak wrote:
> Move the tracking for the DSC stream count from
> intel_crtc_state::dsc.num_streams to
> intel_crtc_state::dsc.slice_config.streams_per_pipe.
> 
> While at it add a TODO comment to read out the full DSC configuration
> from HW including the pipes-per-line and slices-per-stream values.
> 
> Signed-off-by: Imre Deak <imre.deak@intel.com>

Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
> ---
>  drivers/gpu/drm/i915/display/icl_dsi.c             |  4 ++--
>  drivers/gpu/drm/i915/display/intel_display.c       |  2 +-
>  drivers/gpu/drm/i915/display/intel_display_types.h |  1 -
>  drivers/gpu/drm/i915/display/intel_dp.c            |  6 +++---
>  drivers/gpu/drm/i915/display/intel_vdsc.c          | 11 ++++++-----
>  5 files changed, 12 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/icl_dsi.c
> b/drivers/gpu/drm/i915/display/icl_dsi.c
> index 9230792960f29..90076839e7152 100644
> --- a/drivers/gpu/drm/i915/display/icl_dsi.c
> +++ b/drivers/gpu/drm/i915/display/icl_dsi.c
> @@ -1626,9 +1626,9 @@ static int gen11_dsi_dsc_compute_config(struct
> intel_encoder *encoder,
>  
>  	/* FIXME: split only when necessary */
>  	if (crtc_state->dsc.slice_count > 1)
> -		crtc_state->dsc.num_streams = 2;
> +		crtc_state->dsc.slice_config.streams_per_pipe = 2;
>  	else
> -		crtc_state->dsc.num_streams = 1;
> +		crtc_state->dsc.slice_config.streams_per_pipe = 1;
>  
>  	/* FIXME: initialize from VBT */
>  	vdsc_cfg->rc_model_size = DSC_RC_MODEL_SIZE_CONST;
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c
> b/drivers/gpu/drm/i915/display/intel_display.c
> index 04f5c488f3998..aef6cfa7bde8e 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -5450,7 +5450,7 @@ intel_pipe_config_compare(const struct
> intel_crtc_state *current_config,
>  	PIPE_CONF_CHECK_I(dsc.config.nsl_bpg_offset);
>  
>  	PIPE_CONF_CHECK_BOOL(dsc.compression_enable);
> -	PIPE_CONF_CHECK_I(dsc.num_streams);
> +	PIPE_CONF_CHECK_I(dsc.slice_config.streams_per_pipe);
>  	PIPE_CONF_CHECK_I(dsc.compressed_bpp_x16);
>  
>  	PIPE_CONF_CHECK_BOOL(splitter.enable);
> diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h
> b/drivers/gpu/drm/i915/display/intel_display_types.h
> index a3de93cdcbde0..574fc7ff33c97 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> @@ -1305,7 +1305,6 @@ struct intel_crtc_state {
>  		/* Only used for state computation, not read out
> from the HW. */
>  		bool compression_enabled_on_link;
>  		bool compression_enable;
> -		int num_streams;
>  		struct intel_dsc_slice_config {
>  			int pipes_per_line;
>  			int streams_per_pipe;
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> b/drivers/gpu/drm/i915/display/intel_dp.c
> index de59b93388f41..03266511841e2 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -2417,11 +2417,11 @@ int intel_dp_dsc_compute_config(struct
> intel_dp *intel_dp,
>  	 */
>  	if (pipe_config->joiner_pipes && num_joined_pipes == 4 &&
>  	    pipe_config->dsc.slice_count == 12)
> -		pipe_config->dsc.num_streams = 3;
> +		pipe_config->dsc.slice_config.streams_per_pipe = 3;
>  	else if (pipe_config->joiner_pipes || pipe_config-
> >dsc.slice_count > 1)
> -		pipe_config->dsc.num_streams = 2;
> +		pipe_config->dsc.slice_config.streams_per_pipe = 2;
>  	else
> -		pipe_config->dsc.num_streams = 1;
> +		pipe_config->dsc.slice_config.streams_per_pipe = 1;
>  
>  	ret = intel_dp_dsc_compute_params(connector, pipe_config);
>  	if (ret < 0) {
> diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c
> b/drivers/gpu/drm/i915/display/intel_vdsc.c
> index 8aa480e3d1c9d..2b27671f97b32 100644
> --- a/drivers/gpu/drm/i915/display/intel_vdsc.c
> +++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
> @@ -421,7 +421,7 @@ intel_dsc_power_domain(struct intel_crtc *crtc,
> enum transcoder cpu_transcoder)
>  
>  static int intel_dsc_get_vdsc_per_pipe(const struct intel_crtc_state
> *crtc_state)
>  {
> -	return crtc_state->dsc.num_streams;
> +	return crtc_state->dsc.slice_config.streams_per_pipe;
>  }
>  
>  int intel_dsc_get_num_vdsc_instances(const struct intel_crtc_state
> *crtc_state)
> @@ -1023,12 +1023,13 @@ void intel_dsc_get_config(struct
> intel_crtc_state *crtc_state)
>  	if (!crtc_state->dsc.compression_enable)
>  		goto out;
>  
> +	/* TODO: Read out
> slice_config.pipes_per_line/slices_per_stream as well */
>  	if (dss_ctl1 & JOINER_ENABLE && dss_ctl2 & (VDSC2_ENABLE |
> SMALL_JOINER_CONFIG_3_ENGINES))
> -		crtc_state->dsc.num_streams = 3;
> +		crtc_state->dsc.slice_config.streams_per_pipe = 3;
>  	else if (dss_ctl1 & JOINER_ENABLE && dss_ctl2 &
> VDSC1_ENABLE)
> -		crtc_state->dsc.num_streams = 2;
> +		crtc_state->dsc.slice_config.streams_per_pipe = 2;
>  	else
> -		crtc_state->dsc.num_streams = 1;
> +		crtc_state->dsc.slice_config.streams_per_pipe = 1;
>  
>  	intel_dsc_get_pps_config(crtc_state);
>  out:
> @@ -1042,7 +1043,7 @@ static void intel_vdsc_dump_state(struct
> drm_printer *p, int indent,
>  			  "dsc-dss: compressed-bpp:" FXP_Q4_FMT ",
> slice-count: %d, num_streams: %d\n",
>  			  FXP_Q4_ARGS(crtc_state-
> >dsc.compressed_bpp_x16),
>  			  crtc_state->dsc.slice_count,
> -			  crtc_state->dsc.num_streams);
> +			  crtc_state-
> >dsc.slice_config.streams_per_pipe);
>  }
>  
>  void intel_vdsc_state_dump(struct drm_printer *p, int indent,