On Thu, 2025-11-27 at 19:50 +0200, Imre Deak wrote:
> Add tracking for the DP DSC pipes-per-line and slices-per-stream
> value
> in the slice config state and compute the current slices-per-line
> (slice_count) value using this slice config. The slices-per-line
> value
> used atm will be removed by a follow-up change after converting all
> the
> places using it to use the slice config instead.
>
> For now the slices-per-stream value is calculated based on the
> slices-per-line value (slice_count) calculated by the
> drm_dp_dsc_sink_max_slice_count() / intel_dp_dsc_get_slice_count()
> functions. In a follow-up change these functions will be converted to
> calculate the slices-per-stream value directly, along with the
> detailed
> slice configuration.
>
> Signed-off-by: Imre Deak <[email protected]>
> ---
> drivers/gpu/drm/i915/display/intel_dp.c | 32 ++++++++++++++++-------
> --
> 1 file changed, 21 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> b/drivers/gpu/drm/i915/display/intel_dp.c
> index 03266511841e2..d17afc18fcfa7 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -2356,6 +2356,7 @@ int intel_dp_dsc_compute_config(struct intel_dp
> *intel_dp,
> &pipe_config->hw.adjusted_mode;
> int num_joined_pipes =
> intel_crtc_num_joined_pipes(pipe_config);
> bool is_mst = intel_crtc_has_type(pipe_config,
> INTEL_OUTPUT_DP_MST);
> + int slices_per_line;
Why you are not using obvious name for this: slice_count ?
> int ret;
>
> /*
> @@ -2383,30 +2384,26 @@ int intel_dp_dsc_compute_config(struct
> intel_dp *intel_dp,
>
> /* Calculate Slice count */
> if (intel_dp_is_edp(intel_dp)) {
> - pipe_config->dsc.slice_count =
> + slices_per_line =
> drm_dp_dsc_sink_max_slice_count(connector-
> >dp.dsc_dpcd,
> true);
> - if (!pipe_config->dsc.slice_count) {
> + if (!slices_per_line) {
> drm_dbg_kms(display->drm,
> "Unsupported Slice Count %d\n",
> - pipe_config->dsc.slice_count);
> + slices_per_line);
> return -EINVAL;
> }
> } else {
> - u8 dsc_dp_slice_count;
> -
> - dsc_dp_slice_count =
> + slices_per_line =
> intel_dp_dsc_get_slice_count(connector,
> adjusted_mode-
> >crtc_clock,
> adjusted_mode-
> >crtc_hdisplay,
>
> num_joined_pipes);
> - if (!dsc_dp_slice_count) {
> + if (!slices_per_line) {
> drm_dbg_kms(display->drm,
> "Compressed Slice Count not
> supported\n");
> return -EINVAL;
> }
You could share handling of !slices_per_line for DP and eDP.
BR,
Jouni Högander
> -
> - pipe_config->dsc.slice_count = dsc_dp_slice_count;
> }
> /*
> * VDSC engine operates at 1 Pixel per clock, so if peak
> pixel rate
> @@ -2415,14 +2412,27 @@ int intel_dp_dsc_compute_config(struct
> intel_dp *intel_dp,
> * In case of Ultrajoiner along with 12 slices we need to
> use 3
> * VDSC instances.
> */
> + pipe_config->dsc.slice_config.pipes_per_line =
> num_joined_pipes;
> +
> if (pipe_config->joiner_pipes && num_joined_pipes == 4 &&
> - pipe_config->dsc.slice_count == 12)
> + slices_per_line == 12)
> pipe_config->dsc.slice_config.streams_per_pipe = 3;
> - else if (pipe_config->joiner_pipes || pipe_config-
> >dsc.slice_count > 1)
> + else if (pipe_config->joiner_pipes || slices_per_line > 1)
> pipe_config->dsc.slice_config.streams_per_pipe = 2;
> else
> pipe_config->dsc.slice_config.streams_per_pipe = 1;
>
> + pipe_config->dsc.slice_config.slices_per_stream =
> + slices_per_line /
> + pipe_config->dsc.slice_config.pipes_per_line /
> + pipe_config->dsc.slice_config.streams_per_pipe;
> +
> + pipe_config->dsc.slice_count =
> + intel_dsc_line_slice_count(&pipe_config-
> >dsc.slice_config);
> +
> + drm_WARN_ON(display->drm,
> + pipe_config->dsc.slice_count !=
> slices_per_line);
> +
> ret = intel_dp_dsc_compute_params(connector, pipe_config);
> if (ret < 0) {
> drm_dbg_kms(display->drm,
