[Intel-gfx] [PATCH v5 2/9] drm/i915: Define an engine class enum for the uABI

[Tvrtko Ursulin]

On 09/11/2017 09:13, Lionel Landwerlin wrote:
> On 08/11/17 19:14, Chris Wilson wrote:
>> +/*
>> + * Different engines serve different roles, and there may be more 
>> than one
>> + * engine serving each role. enum drm_i915_gem_engine_class provides a
>> + * classification of the role of the engine, which may be used when 
>> requesting
>> + * operations to be performed on a certain subset of engines, or for 
>> providing
>> + * information about that group.
>> + */
>> +enum drm_i915_gem_engine_class {
>> +    I915_ENGINE_CLASS_OTHER = 0,
>> +    I915_ENGINE_CLASS_RENDER = 1,
>> +    I915_ENGINE_CLASS_COPY = 2,
>> +    I915_ENGINE_CLASS_VIDEO = 3,
>> +    I915_ENGINE_CLASS_VIDEO_ENHANCE = 4,
>> +};
>> +
> I've tried to build a bit UI in GPUTop to show this.
> I'm a bit skeptical about the OTHER type because if this enum is meant 
> to be extended, then why do we need an OTHER class? We should create new 
> classes instead.

Good point, I agree that I cannot find a reason why we would have it in 
the uAPI. I suspect I was just doing a copy-paste-transform of the 
hardware definitions from i915_reg.h.

Regards,

Tvrtko