Quoting Souza, Jose (2021-01-04 14:50:59)
> On Thu, 2020-12-31 at 09:17 +0000, Chris Wilson wrote:
> > Quoting Almahallawy, Khaled (2020-12-31 01:24:34)
> > > On Wed, 2020-12-30 at 16:02 -0800, Matt Roper wrote:
> > > > On Wed, Dec 30, 2020 at 10:37:42AM +0000, Chris Wilson wrote:
> > > > > The timeouts are frequent and expected. We will complain if we
> > > > > retry so
> > > > > often as to lose patience and give up, so the cacophony from
> > > > > individual
> > > > > complaints is redundant.
> > > > > 
> > > > > Signed-off-by: Chris Wilson <[email protected]>
> > > > 
> > > > Reviewed-by: Matt Roper <[email protected]>
> > > > 
> > > > > ---
> > > > >  drivers/gpu/drm/i915/display/intel_dp.c | 2 --
> > > > >  1 file changed, 2 deletions(-)
> > > > > 
> > > > > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> > > > > b/drivers/gpu/drm/i915/display/intel_dp.c
> > > > > index 8ae769b18879..704e4cebf7f3 100644
> > > > > --- a/drivers/gpu/drm/i915/display/intel_dp.c
> > > > > +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> > > > > @@ -1613,8 +1613,6 @@ intel_dp_aux_xfer(struct intel_dp *intel_dp,
> > > > >     /* Timeouts occur when the device isn't connected, so they're
> > > > >      * "normal" -- don't fill the kernel log with these */
> > > > >     if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR) {
> > > > > -           drm_dbg_kms(&i915->drm, "%s: timeout (status
> > > > > 0x%08x)\n",
> > > > > -                       intel_dp->aux.name, status);
> > > 
> > > AUX timeout logs are very important for TGL TCSS Display debugging. We
> > > actually can get AUX timeout when the display is connected for the
> > > following reasons:
> > > * If AUX orientation is not configured correctly in BIOS
> > > * If USB3 dock is downgraded to USB2 and SBU/AUX lines are disabled
> > > * When LTTPR/Retimer started to act funny and not configured correctly
> > > by EC
> > > * When we have a bug in the PMC mux configuration because of bug in the
> > > following files: drivers/usb/typec/mux/intel_pmc_mux.c and
> > > drivers/platform/x86/intel_scu_ipc.c
> > > * When user space is not cleanly disconnected all MST connectors for
> > > disconnected MST hub with 2+ display. We will be left with enabled
> > > pipes although the cable is disconnected and next connect of type-c
> > > display will give aux timeout: 
> > >   ** User space fix in Chrome: 
> > > https://chromium-review.googlesource.com/c/chromium/src/+/2512550/ 
> > >   ** WA in driver: https://patchwork.freedesktop.org/patch/395901/ 
> > > 
> > > These logs are especially important for Chrome based platforms with
> > > type-C. Seeing these logs we can know who is screwing up (TCSS driver,
> > > CB, or EC).
> > 
> > Then capture the information you require to analyse your failures.
> > Flooding the debug log makes debugging everything else much, much harder.
> > -Chris
> 
> I agree with Khaled this message is helpful to debug why display is not 
> coming up.

Isn't that the case where it falls through to the later timeout warning?

If there's some information in there to explain a display failure, can
it be extracted automatically? Or to turn the table around, if it is so
useful to debug failures, why do we still see it in CI?
-Chris
_______________________________________________
Intel-gfx mailing list
[email protected]
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Reply via email to