[Intel-gfx] [PATCH 3/7] drm/i915: Always enable execlists on BDW for vgpu

[Zhiyuan Lv]

Hi Daniel,

On Wed, Aug 26, 2015 at 10:50:23AM +0200, Daniel Vetter wrote:
> > > @@ -332,6 +332,12 @@ int i915_gem_context_init(struct drm_device 
> > > *dev)
> > >         if (WARN_ON(dev_priv->ring[RCS].default_context))
> > >                 return 0;
> > >  
> > > +       if (intel_vgpu_active(dev)) {
> > > +               if (WARN_ON(HAS_LOGICAL_RING_CONTEXTS(dev) &&
> > > +                           !i915.enable_execlist))
> > > +                       return 0;
> > > +       }
> > > +
> > 
> > This looks fine to me. Maybe comment might be in place stating that
> > support is not yet implemented, but could be.
> 
> You should fail this instead so that i915.ko knows that the render side of
> the gpu doesn't work. And maybe just DRM_INFO with a useful informational
> notice?

Thanks for the comments! Will change.

> 
> Also same comment here: Don't we need to coordinate this a bit better with
> the host?

In host side, if driver is running in ring buffer mode, we will let GVT-g
initialization fail, so that guest cannot set vgpu active. Would that be good
enough? Thanks!

> -Daniel
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch