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

Chris Wilson
2015-08-20T08:34:15Z

On Thu, Aug 20, 2015 at 03:45:20PM +0800, Zhiyuan Lv wrote:
> Broadwell hardware supports both ring buffer mode and execlist mode.
> When i915 runs inside a VM with Intel GVT-g, we allow execlist mode
> only. The reason is that GVT-g does not support the dynamic mode
> switch between ring buffer mode and execlist mode when running
> multiple virtual machines. Consider that ring buffer mode is legacy
> mode, it makes sense to drop it inside virtual machines.

If that is the case, you should query the host as to what mode it is
running.
-Chris

--
Chris Wilson, Intel Open Source Technology Centre