diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index bbba97c956a297a8204d58a7e3933988410424a2..7765a8b95b9dc51cf47f656568681326b5e3851f 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -468,6 +468,15 @@ int intel_dp_get_link_train_fallback_values(struct intel_dp *intel_dp, struct drm_i915_private *i915 = dp_to_i915(intel_dp); int index; + /* + * TODO: Enable fallback on MST links once MST link compute can handle + * the fallback params. + */ + if (intel_dp->is_mst) { + drm_err(&i915->drm, "Link Training Unsuccessful\n"); + return -1; + } + index = intel_dp_rate_index(intel_dp->common_rates, intel_dp->num_common_rates, link_rate); @@ -6165,7 +6174,17 @@ intel_dp_detect(struct drm_connector *connector, goto out; } - if (intel_dp->reset_link_params) { + /* Read DP Sink DSC Cap DPCD regs for DP v1.4 */ + if (INTEL_GEN(dev_priv) >= 11) + intel_dp_get_dsc_sink_cap(intel_dp); + + intel_dp_configure_mst(intel_dp); + + /* + * TODO: Reset link params when switching to MST mode, until MST + * supports link training fallback params. + */ + if (intel_dp->reset_link_params || intel_dp->is_mst) { /* Initial max link lane count */ intel_dp->max_link_lane_count = intel_dp_max_common_lane_count(intel_dp); @@ -6177,12 +6196,6 @@ intel_dp_detect(struct drm_connector *connector, intel_dp_print_rates(intel_dp); - /* Read DP Sink DSC Cap DPCD regs for DP v1.4 */ - if (INTEL_GEN(dev_priv) >= 11) - intel_dp_get_dsc_sink_cap(intel_dp); - - intel_dp_configure_mst(intel_dp); - if (intel_dp->is_mst) { /* * If we are in MST mode then this connector