Re: [PATCH] drm/i915: Assert we hold the CRTC powerwell for generating vblank interrupts

Chris Wilson
2016-10-13T15:06:43Z

On Thu, Oct 13, 2016 at 04:17:07PM +0200, Daniel Vetter wrote:
> On Wed, Oct 12, 2016 at 07:21:44AM +0200, Maarten Lankhorst wrote:
> > I don't see a nice way to do this, it probably means we shouldn't do this at all..
> > Maybe have a function look at dev_priv->power_domains.domain_use_count[[POWER_DOMAIN_PIPE(pipe)] >= 1?
> > It's potentially racy but I don't see a nice way to check, apart from hoping we handle the drm vblank on/off
> > calls correctly.
> >
> > The only other way I see is demidlayering vblank.
>
> Or switch over power domains over to the core power domain stuff. There's
> a reason those are protected with spinlocks, so that you can do these
> kinds of checks ;-)

Why not both! They're on the wishlist somewhere.
-Chris

--
Chris Wilson, Intel Open Source Technology Centre