On Tue, Feb 13, 2024 at 01:30:57PM +0200, Jani Nikula wrote: > Rename intel_dp_can_mst() to intel_dp_mst_detect(), and move all DP MST > detect debug logging there. Debug log the sink's MST capability, > including single-stream sideband messaging support, and the decision > whether to enable MST mode or not. Do this regardless of whether we're > actually enabling MST or not. > > Cc: Arun R Murthy <arun.r.murthy@xxxxxxxxx> > Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> > --- > drivers/gpu/drm/i915/display/intel_dp.c | 45 +++++++++++++++++-------- > 1 file changed, 31 insertions(+), 14 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c > index a1c304f451bd..944f566525dd 100644 > --- a/drivers/gpu/drm/i915/display/intel_dp.c > +++ b/drivers/gpu/drm/i915/display/intel_dp.c > @@ -4007,31 +4007,48 @@ intel_dp_get_dpcd(struct intel_dp *intel_dp) > intel_dp->downstream_ports) == 0; > } > > +static const char *intel_dp_mst_mode_str(enum drm_dp_mst_mode mst_mode) > +{ > + if (mst_mode == DRM_DP_SST_SIDEBAND_MSG) > + return "single-stream sideband messaging"; > + else > + return str_yes_no(mst_mode == DRM_DP_MST); I wonder if this should also just say "sst"/"mst"/"sst sideband" etc. Shrug. Reviewed-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > +} > + > static bool > -intel_dp_can_mst(struct intel_dp *intel_dp) > +intel_dp_mst_detect(struct intel_dp *intel_dp) > { > struct drm_i915_private *i915 = dp_to_i915(intel_dp); > + struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base; > + enum drm_dp_mst_mode sink_mst_mode; > + enum drm_dp_mst_mode mst_detect; > + > + sink_mst_mode = drm_dp_read_mst_cap(&intel_dp->aux, intel_dp->dpcd); > + > + if (i915->display.params.enable_dp_mst && > + intel_dp_mst_source_support(intel_dp) && > + sink_mst_mode == DRM_DP_MST) > + mst_detect = DRM_DP_MST; > + else > + mst_detect = DRM_DP_SST; > > - return i915->display.params.enable_dp_mst && > - intel_dp_mst_source_support(intel_dp) && > - drm_dp_read_mst_cap(&intel_dp->aux, intel_dp->dpcd) == DRM_DP_MST; > + drm_dbg_kms(&i915->drm, > + "[ENCODER:%d:%s] MST support: port: %s, sink: %s, modparam: %s -> enable: %s\n", > + encoder->base.base.id, encoder->base.name, > + str_yes_no(intel_dp_mst_source_support(intel_dp)), > + intel_dp_mst_mode_str(sink_mst_mode), > + str_yes_no(i915->display.params.enable_dp_mst), > + intel_dp_mst_mode_str(mst_detect)); > + > + return mst_detect != DRM_DP_SST; > } > > static void > intel_dp_configure_mst(struct intel_dp *intel_dp) > { > struct drm_i915_private *i915 = dp_to_i915(intel_dp); > - struct intel_encoder *encoder = > - &dp_to_dig_port(intel_dp)->base; > bool sink_can_mst = drm_dp_read_mst_cap(&intel_dp->aux, intel_dp->dpcd) == DRM_DP_MST; > > - drm_dbg_kms(&i915->drm, > - "[ENCODER:%d:%s] MST support: port: %s, sink: %s, modparam: %s\n", > - encoder->base.base.id, encoder->base.name, > - str_yes_no(intel_dp_mst_source_support(intel_dp)), > - str_yes_no(sink_can_mst), > - str_yes_no(i915->display.params.enable_dp_mst)); > - > if (!intel_dp_mst_source_support(intel_dp)) > return; > > @@ -5390,7 +5407,7 @@ intel_dp_detect_dpcd(struct intel_dp *intel_dp) > connector_status_connected : connector_status_disconnected; > } > > - if (intel_dp_can_mst(intel_dp)) > + if (intel_dp_mst_detect(intel_dp)) > return connector_status_connected; > > /* If no HPD, poke DDC gently */ > -- > 2.39.2 -- Ville Syrjälä Intel