[Intel-gfx] [PATCH] drm/i915/dp: return proper DPRX link training result

[Vudum, Lakshminarayana]

Here is the gitlab issue https://gitlab.freedesktop.org/drm/intel/-/issues/4002

Lakshmi.
-----Original Message-----
From: Saarinen, Jani <jani.saarinen at intel.com> 
Sent: Monday, August 23, 2021 1:39 AM
To: Ville Syrjälä <ville.syrjala at linux.intel.com>; Deak, Imre <imre.deak at intel.com>; Vudum, Lakshminarayana <lakshminarayana.vudum at intel.com>
Cc: Lee, Shawn C <shawn.c.lee at intel.com>; Almahallawy, Khaled <khaled.almahallawy at intel.com>; intel-gfx at lists.freedesktop.org; Chiou, Cooper <cooper.chiou at intel.com>; Tseng, William <william.tseng at intel.com>
Subject: RE: [Intel-gfx] [PATCH] drm/i915/dp: return proper DPRX link training result

Hi, 

> -----Original Message-----
> From: Intel-gfx <intel-gfx-bounces at lists.freedesktop.org> On Behalf Of 
> Ville Syrjälä
> Sent: lauantai 21. elokuuta 2021 1.20
> To: Deak, Imre <imre.deak at intel.com>
> Cc: Lee, Shawn C <shawn.c.lee at intel.com>; Almahallawy, Khaled 
> <khaled.almahallawy at intel.com>; intel-gfx at lists.freedesktop.org; 
> Chiou, Cooper <cooper.chiou at intel.com>; Tseng, William 
> <william.tseng at intel.com>
> Subject: Re: [Intel-gfx] [PATCH] drm/i915/dp: return proper DPRX link 
> training result
> 
> On Wed, Aug 18, 2021 at 07:17:12PM +0300, Imre Deak wrote:
> > On Wed, Aug 18, 2021 at 06:09:43PM +0300, Lee, Shawn C wrote:
> > > On Tue, 2021-07-07, Lee Shawn C <shawn.c.lee at intel.com> wrote:
> > > >On Tue, 2021-07-07, Almahallawy, Khaled 
> > > ><khaled.almahallawy at intel.com>
> wrote:
> > > >>I believe Imre's LT fallback:
> > > >>https://github.com/ideak/linux/commits/linktraining-fallback-fix  
> > > >>and Chrome
> user space fix:
> > > >>https://chromium-review.googlesource.com/c/chromium/src/+/300348
> > > >>7 should address Chrome concerns for LT failure and LTTPRs
> > > >>
> > > >
> > > >Thanks for comment! The new fallback patch should help on this DPRX problem.
> > > >One more thing. If driver did not handle DPRX link train failed properly.
> > > >It would impact link layer compliance test case in below.
> > > >
> > > >400.3.1.3
> > > >400.3.1.4
> > > >400.3.1.6
> > > >400.3.1.12
> > > >400.3.1.13
> > > >400.3.1.14
> > > >
> > > >Best regards,
> > > >Shawn
> > > >
> > >
> > > Hi all, before Imre's patch series land on upstream driver. The 
> > > link train failed handling works for LTTPR only. But DPRX does 
> > > not. Could you please consider to have this change as temporary solution? Thanks!
> >
> > I sent already fixing this, see
> > https://lore.kernel.org/intel-gfx/20201027133600.3656665-1-imre.deak
> > @i
> > ntel.com/
> >
> > but it fell through the cracks. Applied now your patch, thanks.
> 
> We seem to have a tgl that fails consistently at DPRX link training:
> https://intel-gfx-ci.01.org/tree/drm-tip/fi-tgl-1115g4.html
Yes, @Vudum, Lakshminarayana what is gitlab issue for this? 
[Lakshmi] https://gitlab.freedesktop.org/drm/intel/-/issues/4002
> 
> Previously the error went unnoticed.
> 
> --
> Ville Syrjälä
> Intel