[Intel-gfx] [PATCH] drm/i915: Introduce struct class_instance for engines across the uAPI

[Chris Wilson]

Quoting Rodrigo Vivi (2019-04-29 18:08:24)
> On Fri, Apr 12, 2019 at 07:51:47AM +0100, Chris Wilson wrote:
> > SSEU reprogramming of the context introduced the notion of engine class
> > and instance for a forwards compatible method of describing any engine
> > beyond the old execbuf interface. We wish to adopt this class:instance
> > description for more interfaces, so pull it out into a separate type for
> > userspace convenience.
> > 
> > References: e46c2e99f600 ("drm/i915: Expose RPCS (SSEU) configuration to userspace (Gen11 only)")
> 
> I'm a bit confused here how/why this References become a Fixes.

It's required to make sure that the kernel was not released with
incompatible ABI.
-Chris