[Intel-gfx] [PATCH] drm/i915/display: Reduce log level for DP command signal timeout

[Vanshidhar Konda]

On Thu, Mar 14, 2019 at 10:47:56PM +0200, Ville Syrjälä wrote:
>On Thu, Mar 14, 2019 at 01:26:00PM -0700, Vanshidhar Konda wrote:
>> On Thu, Mar 14, 2019 at 08:39:11PM +0200, Ville Syrjälä wrote:
>> >On Thu, Mar 14, 2019 at 10:58:49AM -0700, Vanshidhar Konda wrote:
>> >> The log level for timeout after waiting for a signal on the  DP aux
>> >> channel control register is set to DRM_ERROR. But this is timeout not a
>> >> fatal error as the driver is expected to retry the command. Failure
>> >> after all retries is already captured as an error. Hence, reducing the
>> >> log for a timeout to warning instead of error.
>> >> ---
>> >>  drivers/gpu/drm/i915/intel_dp.c | 2 +-
>> >>  1 file changed, 1 insertion(+), 1 deletion(-)
>> >>
>> >> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
>> >> index 47857f96c3b1..f51e8b2ccb17 100644
>> >> --- a/drivers/gpu/drm/i915/intel_dp.c
>> >> +++ b/drivers/gpu/drm/i915/intel_dp.c
>> >> @@ -1069,7 +1069,7 @@ intel_dp_aux_wait_done(struct intel_dp *intel_dp)
>> >>  	trace_i915_reg_rw(false, ch_ctl, status, sizeof(status), true);
>> >>
>> >>  	if (!done)
>> >> -		DRM_ERROR("dp aux hw did not signal timeout!\n");
>> >> +		DRM_WARN("dp aux hw did not signal timeout!\n");
>> >
>> >IIRC this indicates the hw is broken.
>> >
>> Does this indicate an issue with Intel GFX/display device, or the
>> display/monitor connected to the DP port?
>>
>> FYI, this is for FDO #109982
>> (https://bugzilla.freedesktop.org/show_bug.cgi?id=109982).
>
>There's nothing connected I believe. But in either case I believe

>From the two logs for the issue, e-DP1 is the only display connected to
the test machine when it generated this error.

>the aux hw should terminate with a proper timeout. I'm tempted to

If we think that there should be no timeout, would it make more sense to
return an error to the caller and having the caller handle the error?

>blame the typec/tbt stuff here too.
>
>>
>> >From the logs, it seems like this timeout only occurs once. The next try
>> succeeds without issues.
>>
>> >>  #undef C
>> >>
>> >>  	return status;
>> >> --
>> >> 2.20.1
>> >>
>> >> _______________________________________________
>> >> Intel-gfx mailing list
>> >> Intel-gfx at lists.freedesktop.org
>> >> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
>> >
>> >--
>> >Ville Syrjälä
>> >Intel
>
>-- 
>Ville Syrjälä
>Intel