[Intel-gfx] Regression on 5.19.12, display flickering on Framework laptop

Tue Oct 4 12:57:38 UTC 2022

On Tue, Oct 04, 2022 at 03:35:44PM +0300, Ville Syrjälä wrote:
> On Mon, Oct 03, 2022 at 08:28:50PM +0200, Thorsten Leemhuis wrote:
> > 
> > 
> > On 03.10.22 19:48, Ville Syrjälä wrote:
> > > On Mon, Oct 03, 2022 at 08:45:18PM +0300, Ville Syrjälä wrote:
> > >> On Sat, Oct 01, 2022 at 12:07:39PM +0200, Thorsten Leemhuis wrote:
> > >>> On 30.09.22 14:26, Jerry Ling wrote:
> > >>>>
> > >>>> looks like someone has done it:
> > >>>> https://bbs.archlinux.org/viewtopic.php?pid=2059823#p2059823
> > >>>>
> > >>>> and the bisect points to:
> > >>>>
> > >>>> |# first bad commit: [fc6aff984b1c63d6b9e54f5eff9cc5ac5840bc8c]
> > >>>> drm/i915/bios: Split VBT data into per-panel vs. global parts Best, Jerry |
> > >>>
> > >>> FWIW, that's 3cf050762534 in mainline. Adding Ville, its author to the
> > >>> list of recipients.
> > >>
> > >> I definitely had no plans to backport any of that stuff,
> > >> but I guess the automagics did it anyway.
> > >>
> > >> Looks like stable is at least missing this pile of stuff:
> > >> 50759c13735d drm/i915/pps: Keep VDD enabled during eDP probe
> > >> 67090801489d drm/i915/pps: Reinit PPS delays after VBT has been fully parsed
> > >> 8e75e8f573e1 drm/i915/pps: Split PPS init+sanitize in two
> > >> 586294c3c186 drm/i915/pps: Stash away original BIOS programmed PPS delays
> > >> 89fcdf430599 drm/i915/pps: Don't apply quirks/etc. to the VBT PPS delays if they haven't been initialized
> > >> 60b02a09598f drm/i915/pps: Introduce pps_delays_valid()
> > >>
> > >> But dunno if even that is enough.
> > 
> > If you need testers: David (now CCed) apparently has a affected machine
> > and offered to test patches in a different subthread of this thread.
> > 
> > >> This bug report is probably the same thing:
> > >> https://gitlab.freedesktop.org/drm/intel/-/issues/7013
> > 
> > Sounds like it.
> > 
> >  > Also cc intel-gfx...
> > 
> > Ahh, sorry, should have done that when I CCed you.
> 
> After looking at some logs we do end up with potentially bogus
> panel power sequencing delays, which may harm the LCD panel.
> 
> 
> Greg, I recommend immediate revert of this stuff, and new stable
> release ASAP. Plus a recommendation that no one using laptops
> with Intel GPUs run 5.19.12.

Ok, will do, I'll go do that right now, thanks and sorry for the
problems.

greg k-h