[Intel-gfx] [PATCH] drm/i915: Recognise non-VGA display devices

[Chris Wilson]

On Fri, 21 Jan 2011 08:49:59 +1000, Dave Airlie <airlied at gmail.com> wrote:
> On Fri, Jan 21, 2011 at 1:07 AM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> > Starting with SandyBridge (though possible with earlier hacked BIOSes),
> > the BIOS may initialise the IGFX as secondary to a discrete GPU. Prior,
> > it would simply disable the integrated GPU. In such a configuration, the
> > IGFX is not a primary VGA controller and so should not take part in VGA
> > arbitration.
> 
> VGA arb shouldn't happen for any devices not VGA class, it shouldn't place the
> devices into the arb list at all in this case.

Right, it doesn't happen, but i915 also need not to throw an error when
vgaarb rejects the device as being !DISPLAY_VGA.

I'll try and update the comments to explain why I've chosen to handle it
this way.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre