On Thu, Aug 24, 2023 at 11:04:56AM +0300, Imre Deak wrote:
> Factor out helpers that DP / DP_MST encoders can use to compute the link
> rate/lane count and bpp limits. A follow-up patch will call these to
> recalculate the limits if DSC compression is required.
>
> Signed-off-by: Imre Deak <imre.d...@intel.com>
> ---
> drivers/gpu/drm/i915/display/intel_dp.c | 61 +++++++++++++--------
> drivers/gpu/drm/i915/display/intel_dp_mst.c | 52 ++++++++++--------
> 2 files changed, 68 insertions(+), 45 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> b/drivers/gpu/drm/i915/display/intel_dp.c
> index 7067ee3a4bd36..53697f361f950 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -2187,29 +2187,25 @@ int intel_dp_dsc_compute_config(struct intel_dp
> *intel_dp,
> return 0;
> }
>
> -static int
> -intel_dp_compute_link_config(struct intel_encoder *encoder,
> - struct intel_crtc_state *pipe_config,
> - struct drm_connector_state *conn_state,
> - bool respect_downstream_limits)
> +static void
> +intel_dp_compute_config_limits(struct intel_dp *intel_dp,
> + struct intel_crtc_state *crtc_state,
> + bool respect_downstream_limits,
> + struct link_config_limits *limits)
> {
> - struct drm_i915_private *i915 = to_i915(encoder->base.dev);
> - struct intel_crtc *crtc = to_intel_crtc(pipe_config->uapi.crtc);
> + struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> const struct drm_display_mode *adjusted_mode =
> - &pipe_config->hw.adjusted_mode;
> - struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
> - struct link_config_limits limits;
> - bool joiner_needs_dsc = false;
> - int ret;
> + &crtc_state->hw.adjusted_mode;
>
> - limits.min_rate = intel_dp_common_rate(intel_dp, 0);
> - limits.max_rate = intel_dp_max_link_rate(intel_dp);
> + limits->min_rate = intel_dp_common_rate(intel_dp, 0);
> + limits->max_rate = intel_dp_max_link_rate(intel_dp);
>
> - limits.min_lane_count = 1;
> - limits.max_lane_count = intel_dp_max_lane_count(intel_dp);
> + limits->min_lane_count = 1;
> + limits->max_lane_count = intel_dp_max_lane_count(intel_dp);
>
> - limits.min_bpp = intel_dp_min_bpp(pipe_config->output_format);
> - limits.max_bpp = intel_dp_max_bpp(intel_dp, pipe_config,
> respect_downstream_limits);
> + limits->min_bpp = intel_dp_min_bpp(crtc_state->output_format);
> + limits->max_bpp = intel_dp_max_bpp(intel_dp, crtc_state,
> + respect_downstream_limits);
>
> if (intel_dp->use_max_params) {
> /*
> @@ -2220,16 +2216,35 @@ intel_dp_compute_link_config(struct intel_encoder
> *encoder,
> * configuration, and typically on older panels these
> * values correspond to the native resolution of the panel.
> */
> - limits.min_lane_count = limits.max_lane_count;
> - limits.min_rate = limits.max_rate;
> + limits->min_lane_count = limits->max_lane_count;
> + limits->min_rate = limits->max_rate;
> }
>
> - intel_dp_adjust_compliance_config(intel_dp, pipe_config, &limits);
> + intel_dp_adjust_compliance_config(intel_dp, crtc_state, limits);
Annoying little bugger that mutates the crtc_state. Would be nice
to relocate that small part somewhere else so that we could constify
things more...
Anyways
Reviewed-by: Ville Syrjälä <ville.syrj...@linux.intel.com>
>
> drm_dbg_kms(&i915->drm, "DP link computation with max lane count %i "
> "max rate %d max bpp %d pixel clock %iKHz\n",
> - limits.max_lane_count, limits.max_rate,
> - limits.max_bpp, adjusted_mode->crtc_clock);
> + limits->max_lane_count, limits->max_rate,
> + limits->max_bpp, adjusted_mode->crtc_clock);
> +}
> +
> +static int
> +intel_dp_compute_link_config(struct intel_encoder *encoder,
> + struct intel_crtc_state *pipe_config,
> + struct drm_connector_state *conn_state,
> + bool respect_downstream_limits)
> +{
> + struct drm_i915_private *i915 = to_i915(encoder->base.dev);
> + struct intel_crtc *crtc = to_intel_crtc(pipe_config->uapi.crtc);
> + const struct drm_display_mode *adjusted_mode =
> + &pipe_config->hw.adjusted_mode;
> + struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
> + struct link_config_limits limits;
> + bool joiner_needs_dsc = false;
> + int ret;
> +
> + intel_dp_compute_config_limits(intel_dp, pipe_config,
> + respect_downstream_limits, &limits);
>
> if (intel_dp_need_bigjoiner(intel_dp, adjusted_mode->crtc_hdisplay,
> adjusted_mode->crtc_clock))
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index 3eb085fbc7c82..218c2dfd57adc 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -306,6 +306,35 @@ static bool intel_dp_mst_has_audio(const struct
> drm_connector_state *conn_state)
> return intel_conn_state->force_audio == HDMI_AUDIO_ON;
> }
>
> +static void
> +intel_dp_mst_compute_config_limits(struct intel_dp *intel_dp,
> + struct intel_crtc_state *crtc_state,
> + struct link_config_limits *limits)
> +{
> + /*
> + * for MST we always configure max link bw - the spec doesn't
> + * seem to suggest we should do otherwise.
> + */
> + limits->min_rate = limits->max_rate =
> + intel_dp_max_link_rate(intel_dp);
> +
> + limits->min_lane_count = limits->max_lane_count =
> + intel_dp_max_lane_count(intel_dp);
> +
> + limits->min_bpp = intel_dp_min_bpp(crtc_state->output_format);
> + /*
> + * FIXME: If all the streams can't fit into the link with
> + * their current pipe_bpp we should reduce pipe_bpp across
> + * the board until things start to fit. Until then we
> + * limit to <= 8bpc since that's what was hardcoded for all
> + * MST streams previously. This hack should be removed once
> + * we have the proper retry logic in place.
> + */
> + limits->max_bpp = min(crtc_state->pipe_bpp, 24);
> +
> + intel_dp_adjust_compliance_config(intel_dp, crtc_state, limits);
> +}
> +
> static int intel_dp_mst_compute_config(struct intel_encoder *encoder,
> struct intel_crtc_state *pipe_config,
> struct drm_connector_state *conn_state)
> @@ -329,28 +358,7 @@ static int intel_dp_mst_compute_config(struct
> intel_encoder *encoder,
> intel_dp_mst_has_audio(conn_state) &&
> intel_audio_compute_config(encoder, pipe_config, conn_state);
>
> - /*
> - * for MST we always configure max link bw - the spec doesn't
> - * seem to suggest we should do otherwise.
> - */
> - limits.min_rate =
> - limits.max_rate = intel_dp_max_link_rate(intel_dp);
> -
> - limits.min_lane_count =
> - limits.max_lane_count = intel_dp_max_lane_count(intel_dp);
> -
> - limits.min_bpp = intel_dp_min_bpp(pipe_config->output_format);
> - /*
> - * FIXME: If all the streams can't fit into the link with
> - * their current pipe_bpp we should reduce pipe_bpp across
> - * the board until things start to fit. Until then we
> - * limit to <= 8bpc since that's what was hardcoded for all
> - * MST streams previously. This hack should be removed once
> - * we have the proper retry logic in place.
> - */
> - limits.max_bpp = min(pipe_config->pipe_bpp, 24);
> -
> - intel_dp_adjust_compliance_config(intel_dp, pipe_config, &limits);
> + intel_dp_mst_compute_config_limits(intel_dp, pipe_config, &limits);
>
> ret = intel_dp_mst_compute_link_config(encoder, pipe_config,
> conn_state, &limits);
> --
> 2.37.2
--
Ville Syrjälä
Intel
