[Intel-gfx] [PATCH 4/5] drm/i915: Provide more information on DP AUX failures

[Lucas De Marchi]

On Fri, Oct 25, 2019 at 04:06:22PM -0700, Matt Roper wrote:
>We're seeing some failures where an aux transaction still shows as
>'busy' well after the timeout limit that the hardware is supposed to
>enforce.  Improve the error message so that we can see exactly which aux
>channel this error happened on and what the status bits were during this
>case that isn't supposed to happen.
>
>Signed-off-by: Matt Roper <matthew.d.roper at intel.com>
>---
> drivers/gpu/drm/i915/display/intel_dp.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
>diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
>index 65bab46f7b43..2b4915b5cf52 100644
>--- a/drivers/gpu/drm/i915/display/intel_dp.c
>+++ b/drivers/gpu/drm/i915/display/intel_dp.c
>@@ -1190,7 +1190,8 @@ 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_ERROR("%s did not complete or timeout within 10ms (status 0x%08x)\n",
>+			  intel_dp->aux.name ?: "AUX", status);

maybe a "const timeout_msec = 10" and use it both here and above to
avoid mismatch in future? However I'm not sure it's worth... up to you.

intel_dp_aux_init set aux.name to kasprintf() and we can't possibly
initiate aux transactions before that init.
intel_dp_connector_register() also doesn't handle aux.name == NULL, so
whay are we checking it heere?

Lucas De Marchi

> #undef C
>
> 	return status;
>-- 
>2.21.0
>
>_______________________________________________
>Intel-gfx mailing list
>Intel-gfx at lists.freedesktop.org
>https://lists.freedesktop.org/mailman/listinfo/intel-gfx