Re: [PATCH] drm/i915/dp: Fix the PSR debugfs entries wrt. MST connectors

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

On Wed, 2024-01-03 at 13:20 +0200, Imre Deak wrote:
> On Wed, Jan 03, 2024 at 01:08:05PM +0200, Hogander, Jouni wrote:
> > On Wed, 2024-01-03 at 13:00 +0200, Imre Deak wrote:
> > > MST connectors don't have a static attached encoder, as their
> > > encoder
> > > can change depending on the pipe they use; so the encoder for an
> > > MST
> > > connector can't be retrieved using intel_dp_attached_encoder()
> > > (which
> > > may return NULL for MST). Most of the PSR debugfs entries depend
> > > on a
> > > static connector -> encoder mapping which is only true for eDP
> > > and
> > > SST
> > > DP connectors and not for MST. These debugfs entries were enabled
> > > for
> > > MST connectors as well recently to provide PR information for
> > > them,
> > > but
> > > handling MST connectors needs more changes. Fix this by re-
> > > disabling
> > > for
> > > now the PSR entries on MST connectors.
> > > 
> > > Fixes: ef75c25e8fed ("drm/i915/panelreplay: Debugfs support for
> > > panel
> > > replay")
> > > Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9850
> > > Cc: Animesh Manna <animesh.manna@intel.com>
> > > Cc: Jouni Högander <jouni.hogander@intel.com>
> > > Signed-off-by: Imre Deak <imre.deak@intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/display/intel_psr.c | 7 ++-----
> > >  1 file changed, 2 insertions(+), 5 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/display/intel_psr.c
> > > b/drivers/gpu/drm/i915/display/intel_psr.c
> > > index 494d08817d71e..b5b9340e505e3 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_psr.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> > > @@ -3310,11 +3310,8 @@ void
> > > intel_psr_connector_debugfs_add(struct
> > > intel_connector *connector)
> > >         struct drm_i915_private *i915 = to_i915(connector-
> > > >base.dev);
> > >         struct dentry *root = connector->base.debugfs_entry;
> > > 
> > > -       if (connector->base.connector_type !=
> > > DRM_MODE_CONNECTOR_eDP)
> > > {
> > > -               if (!(HAS_DP20(i915) &&
> > > -                     connector->base.connector_type ==
> > > DRM_MODE_CONNECTOR_DisplayPort))
> > > -                       return;
> > > -       }
> > > +       if (connector->base.connector_type !=
> > > DRM_MODE_CONNECTOR_eDP)
> > > +               return;
> > 
> > Would it be possible to disable it only for MST connector? I think
> > this
> > is disabling it also for DP SST, no?
> 
> Yes, it keeps it enabled only for eDP. It could be enabled for SST as
> well yes, but I thought as a fix the above is better, adding support
> for
> other connector types as a follow up.

if (connector->mst_port || !(HAS_DP20(i915) &&
connectorbase.connector_type == DRM_MODE_CONNECTOR_DisplayPort))
    return;

Is it possible to use this instead?

BR,

Jouni Högander

> 
> > BR,
> > 
> > Jouni Högander
> > > 
> > >         debugfs_create_file("i915_psr_sink_status", 0444, root,
> > >                             connector,
> > > &i915_psr_sink_status_fops);
> >