drm/i915/dp: Reset intel_dp->link_trained before retraining the link

Regularly retraining a link during an atomic commit happens with the
given pipe/link already disabled and hence intel_dp->link_trained being
false. Ensure this also for retraining a DP SST link via direct calls to
the link training functions (vs. an actual commit as for DP MST). So far
nothing depended on this, however the next patch will depend on
link_trained==false for changing the LTTPR mode to non-transparent.

Cc: <stable@vger.kernel.org> # v5.15+
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240708190029.271247-2-imre.deak@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index edfb30857479ab06f11cf10453166ca76fa08b87..d4b1b18453dca504e5aadbd55d755602eb5102a0 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -5305,6 +5305,8 @@ static int intel_dp_retrain_link(struct intel_encoder *encoder,
                const struct intel_crtc_state *crtc_state =
                        to_intel_crtc_state(crtc->base.state);
 
+               intel_dp->link_trained = false;
+
                intel_dp_check_frl_training(intel_dp);
                intel_dp_pcon_dsc_configure(intel_dp, crtc_state);
                intel_dp_start_link_train(NULL, intel_dp, crtc_state);