[Intel-gfx] [PATCH v3] drm/i915: Add Guc/HuC firmware details to error state

[Chris Wilson]

Quoting Michal Wajdeczko (2017-10-20 13:36:59)
> On Fri, 20 Oct 2017 14:21:16 +0200, Chris Wilson  
> <chris at chris-wilson.co.uk> wrote:
> 
> > Quoting Michal Wajdeczko (2017-10-20 13:14:45)
> >> On Fri, 20 Oct 2017 13:44:04 +0200, Chris Wilson
> >> <chris at chris-wilson.co.uk> wrote:
> >>
> >> > Quoting Joonas Lahtinen (2017-10-20 10:41:57)
> >> >> On Thu, 2017-10-19 at 20:23 +0000, Michal Wajdeczko wrote:
> >> >> > @@ -774,6 +793,11 @@ int i915_error_state_to_str(struct
> >> >> drm_i915_error_state_buf *m,
> >> >> >       err_print_capabilities(m, &error->device_info);
> >> >> >       err_print_params(m, &error->params);
> >> >> >
> >> >> > +     if (error->device_info.has_guc) {
> >> >> > +             intel_uc_fw_dump(&error->guc_fw, &p);
> >> >> > +             intel_uc_fw_dump(&error->huc_fw, &p);
> >> >> > +     }
> >> >>
> >> >> I might use "error->{g,h}uc_fw.path" as the condition, for both
> >> >> individually. We will have DMC here in the future, too.
> >> >
> >> > That's the type of predicate I was looking for. If we can tell when  
> >> the
> >> > fw has been loaded just by looking at the uc_fw struct, please do so.
> >>
> >> If you want to include uc fw info only when fw was loaded at capture
> >> moment,
> >> then we can look directly at its "load_status" field:
> >>
> >>         if (error->guc_fw.load_status == INTEL_UC_FIRMWARE_SUCCESS)
> >>
> >> But what if fw was loaded earlier, before error capture is started?
> >> Don't we want to capture whole driver configuration?
> >
> > The goal is to know what the driver/hw was doing at the time of the
> > capture (which we presume is still identical to the hang).
> >
> > At this point, we are just asking ourselves what is the most unambiguous
> > way of printing valid data. We already show has_guc in the output, so it
> > boils down to what was the uc_fw state. It doesn't need to be
> > load_status == SUCCESS, as we should show a failed attempt to upload the
> > fw as well.
> >
> > So intel_uc_fw.size?
> 
> But then in case of zero size fw you will not get info about load failure  
> ;)

Heh, I would just go back and make sure we had a clear well of deducing
when fw was being utilised. Maybe 

	if (uc_fw.load_status != INTEL_UC_FIRMWARE_NONE)

?
-Chris