[Intel-gfx] [PATCH 5/7] drm/i915/uc: Skip reset preparation if GuC is already dead

[Michal Wajdeczko]

On Fri, 17 May 2019 19:14:01 +0200, Chris Wilson  
<chris at chris-wilson.co.uk> wrote:

> Quoting Michal Wajdeczko (2019-05-17 18:11:07)
>> On Fri, 17 May 2019 18:31:31 +0200, Chris Wilson
>> <chris at chris-wilson.co.uk> wrote:
>>
>> > Quoting Michal Wajdeczko (2019-05-17 17:22:25)
>> >> We may skip reset preparation steps if GuC is already sanitized.
>> >>
>> >> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
>> >> Cc: Chris Wilson <chris at chris-wilson.co.uk>
>> >> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
>> >> ---
>> >>  drivers/gpu/drm/i915/intel_uc.c | 3 +++
>> >>  1 file changed, 3 insertions(+)
>> >>
>> >> diff --git a/drivers/gpu/drm/i915/intel_uc.c
>> >> b/drivers/gpu/drm/i915/intel_uc.c
>> >> index 86edfa5ad72e..36c53a42927c 100644
>> >> --- a/drivers/gpu/drm/i915/intel_uc.c
>> >> +++ b/drivers/gpu/drm/i915/intel_uc.c
>> >> @@ -499,6 +499,9 @@ void intel_uc_reset_prepare(struct  
>> drm_i915_private
>> >> *i915)
>> >>         if (!USES_GUC(i915))
>> >>                 return;
>> >>
>> >> +       if (!intel_guc_is_alive(guc))
>> >> +               return;
>> >
>> > Does it not replace "if (!USES_GUC(i915))"?
>>
>> Yes it can, as we will never fetch/upload fw if we don't plan to use it  
>> ;)
>>
>> Btw, I'm thinking of renaming intel_guc_is_alive to intel_guc_is_loaded
>> or intel_guc_is_started to better describe what this function is  
>> reporting,
>> as one can think that intel_guc_is_alive is actually checking that GuC  
>> fw
>> is responsive, which in general might not be the same as "loaded"
>
> Either seems reasonable, though there might be good reason to have both
> :)
>
> intel_guc_is_loaded
> intel_guc_has_started / intel_guc_is_active

On GuC load failure, or on reset, we immediately sanitize fw load status,
so until we provide real runtime connectivity check, if ever be required,
I assume we can stay with just one function: intel_guc_is_loaded, ok?

Michal