Re: [PATCH 0/2] Add quirk to disable PSR 2 on Tongfang PHxTxX1 and PHxTQx1

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

On Thu, 2023-02-23 at 20:02 +0100, Werner Sembach wrote:
> 
> Am 23.02.23 um 19:56 schrieb Werner Sembach:
> > 
> > Am 23.02.23 um 19:26 schrieb Hogander, Jouni:
> > > On Wed, 2023-02-22 at 15:17 +0100, Werner Sembach wrote:
> > > > On these Barebones PSR 2 is recognized as supported but is very
> > > > buggy:
> > > > - Upper third of screen does sometimes not updated, resulting
> > > > in
> > > > disappearing cursors or ghosts of already closed Windows saying
> > > > behind.
> > > > - Approximately 40 px from the bottom edge a 3 pixel wide strip
> > > > of
> > > > randomly
> > > > colored pixels is flickering.
> > > > 
> > > > PSR 1 is working fine however.
> > > > 
> > > > This patchset introduces a new quirk to disable PSR 2
> > > > specifically on
> > > > known
> > > > buggy devices and applies it to the Tongfang PHxTxX1 and
> > > > PHxTQx1
> > > > barebones.
> > > I've been thinking something similar as there is still at least
> > > one
> > > issue which seems to be like panel side issue:
> > > 
> > > https://gitlab.freedesktop.org/drm/intel/-/issues/7836
> > > 
> > > Did you considered dpcd_quirk_list in
> > > drivers/gpu/drm/drm_dp_helper.c?
> > > 
> > > I'm not sure which one is more correct though...
> > Imho, since the proper fix lies within the Intel driver the quirk
> > should also 
> > lie within the Intel driver, because even if the panel has the same
> > problem 
> > combined with an AMD or NVIDIA card the proper fix for them will
> > most likely 
> > be land in the same kernel version. So there could be a period
> > where you no 
> > longer want the quirk for devices combining the panel with an Intel
> > gpu but 
> > still with an AMD GPU or vice versa.
> *the proper fix for them will most likely not be in the same kernel
> version.

Yeah, you are right here. Let's target fixing rootcause for your setup.
First patch from your set could be anyways used for issue mentioned
above.

> > > 
> > > > Signed-off-by: Werner Sembach <wse@tuxedocomputers.com>
> > > > Cc: <stable@vger.kernel.org>
> > > > 
> > > > 

BR,

Jouni Högander