Re: [PATCH 5/8] drm/i915/psr: Clear pr_dpcd as well on disconnect

["Hogander, Jouni" <jouni.hogander@intel.com>]

On Mon, 2025-12-01 at 12:53 +0200, Imre Deak wrote:
> On Fri, Nov 21, 2025 at 01:16:52PM +0200, Jouni Högander wrote:
> > Currently we are leaving pr_dpcd containing Panel Replay capability
> > DPCD
> > registers as it is on disconnect. Clear it as well on disconnect.
> > 
> > Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_dp.c | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> > b/drivers/gpu/drm/i915/display/intel_dp.c
> > index 62808cd35f5f2..7195c408d93ab 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> > @@ -6050,6 +6050,7 @@ intel_dp_detect(struct drm_connector
> > *_connector,
> >  	if (status == connector_status_disconnected) {
> >  		intel_dp_test_reset(intel_dp);
> >  		memset(connector->dp.dsc_dpcd, 0,
> > sizeof(connector->dp.dsc_dpcd));
> > +		memset(connector->dp.pr_dpcd, 0, sizeof(connector-
> > >dp.pr_dpcd));
> 
> What about psr_dpcd?

PSR is only for eDP and can't be disconnected.

> 
> All these resetting of the caps cause a problem if the connector
> needs
> to be modeset after the sink is disconnected (since then the state
> computation for the connector will fail seeing these caps being
> reset).
> Instead the caps should be kept intact here, resetting/reiniting them
> only when a new sink is connected. Since this is a pre-existing
> issue,
> could you add for now a corrsponding FIXME: comment in this patch?

Thank you for pointing this out. I will add the FIXME.

BR,

Jouni Högander

> 
> >  		intel_dp->psr.sink_panel_replay_support = false;
> >  		intel_dp->psr.sink_panel_replay_su_support =
> > false;
> >  		intel_dp->psr.sink_panel_replay_dsc_support =
> > -- 
> > 2.43.0
> >