[Intel-gfx] [PATCH v4 02/22] drm/i915/guc: Don't allow GuC submission

[Michal Wajdeczko]

On Mon, 27 May 2019 13:40:25 +0200, Joonas Lahtinen  
<joonas.lahtinen at linux.intel.com> wrote:

> Quoting Michal Wajdeczko (2019-05-24 02:30:29)
>> Due to the upcoming changes to the GuC ABI interface, we must
>> disable GuC submission mode until final ABI will be available
>> on all GuC firmwares.
>>
>> To avoid regressions on systems configured to run with no longer
>> supported configuration "enable_guc=3" or "enable_guc=1" clear
>> GuC submission bit.
>>
>> v2: force switch to non-GuC submission mode
>>
>> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
>> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
>> Cc: Chris Wilson <chris at chris-wilson.co.uk>
>> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
>> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
>> Cc: John Spotswood <john.a.spotswood at intel.com>
>> Cc: Vinay Belgaumkar <vinay.belgaumkar at intel.com>
>> Cc: Tony Ye <tony.ye at intel.com>
>> Cc: Anusha Srivatsa <anusha.srivatsa at intel.com>
>> Cc: Jeff Mcgee <jeff.mcgee at intel.com>
>> Cc: Antonio Argenziano <antonio.argenziano at intel.com>
>> Cc: Sujaritha Sundaresan <sujaritha.sundaresan at intel.com>
>> Cc: Martin Peres <martin.peres at linux.intel.com>
>> Acked-by: Martin Peres <martin.peres at linux.intel.com>
>
>> diff --git a/drivers/gpu/drm/i915/intel_uc.c  
>> b/drivers/gpu/drm/i915/intel_uc.c
>> index 1a265fbd95c7..f66105d756df 100644
>> --- a/drivers/gpu/drm/i915/intel_uc.c
>> +++ b/drivers/gpu/drm/i915/intel_uc.c
>> @@ -298,6 +307,10 @@ int intel_uc_init(struct drm_i915_private *i915)
>>         if (!HAS_GUC(i915))
>>                 return -ENODEV;
>>
>> +       /* XXX: GuC submission is unavailable for now */
>> +       if (USES_GUC_SUBMISSION(i915))
>> +               return -EIO;
>> +
>
> This would be a driver programmer error, wouldn't it?
>
> Maybe add GEM_BUG_ON() to the later branch that does the check?

Yes as this should never happen now as in v2 we forced non-GuC submission
mode (it was needed only in v1 where we were just printing message)

Thanks for catching that!

>
> Regards, Joonas