Art, any comment here? I just checked and the W/a 1143 is implemented as described, but it is failing HDMI on this hybrid system. > On Aug 12, 2020, at 9:07 PM, Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> wrote: > > Hi, > > There's a regression reported that HDMI output stops working after os upgrade: > https://bugs.launchpad.net/bugs/1871721 > > Here's the bisect result: > 0519c102f5285476d7868a387bdb6c58385e4074 is the first bad commit > commit 0519c102f5285476d7868a387bdb6c58385e4074 > Author: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Date: Mon Jan 22 19:41:31 2018 +0200 > > drm/i915: Implement display w/a #1143 > > Apparently SKL/KBL/CFL need some manual help to get the > programmed HDMI vswing to stick. Implement the relevant > workaround (display w/a #1143). > > Note that the relevant chicken bits live in a transcoder register > even though the bits affect a specific DDI port rather than a > specific transcoder. Hence we must pick the correct transcoder > register instance based on the port rather than based on the > cpu_transcoder. > > Also note that for completeness I included support for DDI A/E > in the code even though we never have HDMI on those ports. > > v2: CFL needs the w/a as well (Rodrigo and Art) > > Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> > Cc: Art Runyan <arthur.j.runyan@xxxxxxxxx> > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Link: https://patchwork.freedesktop.org/patch/msgid/20180122174131.28046-1-ville.syrjala@xxxxxxxxxxxxxxx > Reviewed-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> > > > dmesg from drm-tip with drm.debug=0xe can be found here: > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1871721/comments/64 > > Kai-Heng _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
