On Thu, May 23, 2024 at 06:43:40PM +0300, Ville Syrjälä wrote: > On Thu, May 23, 2024 at 06:29:21PM +0300, Imre Deak wrote: > > On Thu, May 23, 2024 at 06:08:40PM +0300, Ville Syrjälä wrote: > > > On Mon, May 20, 2024 at 09:58:10PM +0300, Imre Deak wrote: > > > > Simplify things by retraining a DP link if a bad link is detected in the > > > > connector detect handler from the encoder's check link state work, > > > > similarly to how this is done after a modeset link training failure. > > > > > > > > Signed-off-by: Imre Deak <[email protected]> > > > > --- > > > > drivers/gpu/drm/i915/display/intel_dp.c | 7 ++----- > > > > 1 file changed, 2 insertions(+), 5 deletions(-) > > > > > > > > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c > > > > b/drivers/gpu/drm/i915/display/intel_dp.c > > > > index ff4ed6bb520d8..70b00e5ae7ad7 100644 > > > > --- a/drivers/gpu/drm/i915/display/intel_dp.c > > > > +++ b/drivers/gpu/drm/i915/display/intel_dp.c > > > > @@ -5863,11 +5863,8 @@ intel_dp_detect(struct drm_connector *connector, > > > > * Some external monitors do not signal loss of link > > > > synchronization > > > > * with an IRQ_HPD, so force a link status check. > > > > */ > > > > - if (!intel_dp_is_edp(intel_dp)) { > > > > - ret = intel_dp_retrain_link(encoder, ctx); > > > > - if (ret) > > > > - return ret; > > > > - } > > > > + if (!intel_dp_is_edp(intel_dp)) > > > > + intel_dp_check_link_state(intel_dp); > > > > > > I would like to see this hack nuked entirely. But that > > > could be a followup. > > > > Okay. This tries to keep the current behavior, but can add a note that > > the above workaround can be removed after the link state is checked > > after modesets. > > > > I also wondered about the link state check in the hotplug handler. If > > that's only a way to defer doing this from the HPD IRQ handler - which > > is now changed by patch 13 - that could be also removed eventually? > > Not sure which one you want to removed exactly. I presume there > are still at least these cases we need to handle: > - long HDP dropped and came back without any userspace > initiated modeset in between > -> kick off a retrain from the long HPD handler
I meant this one, but didn't think of the case where the link can be actually retrained after a long HPD. I guess with a full modeset it works, so should continue doing that. > - short HPD indicated some link badness > -> kick off a retrain from the short HDP handler > - link dropped on its own soon after modeset without > any HPD for some reason > -> kick off a retrain from the post modeset link check > > And the one we should remove: > - something weird happened to the link and no one noticed, > and for some random reason userspace just happens to do > a getconnector() which ends up randomly fixing things Yes, this is clear. > Did I miss anything else? > > -- > Ville Syrjälä > Intel
