On Fri, Jan 06, 2023 at 09:30:56PM +0100, Daniel Vetter wrote: > On Fri, Jan 06, 2023 at 11:33:06AM -0800, Brian Norris wrote: > > On Fri, Jan 06, 2023 at 07:17:53PM +0100, Daniel Vetter wrote: > > > - fake vblanks with hrtimer, because on most hw when you turn off the crtc > > > the vblanks are also turned off, and so your compositor would still > > > hang. The vblank machinery already has all the code to make this happen > > > (and if it's not all, then i915 psr code should have it). > > > > Is a timer better than an interrupt? I'm pretty sure the vblank > > interrupts still can fire on Rockchip CRTC (VOP) (see also the other > > branch of this thread), so this isn't really necessary. (IGT vblank > > tests pass without hanging.) Unless you simply prefer a fake timer for > > some reason. > > > > Also, I still haven't found that fake timer machinery, but maybe I just > > don't know what I'm looking for. > > I ... didn't find it either. I'm honestly not sure whether this works for > intel, or whether we do something silly like disable self-refresh when a > vblank interrupt is pending :-/ Intel hardware doesn't enter PSR while the vblank interrupt is enabled. -- Ville Syrjälä Intel
