[Intel-gfx] [PATCH] drm/i915: Verify power domains after enabling them

[Imre Deak]

On Fri, Aug 17, 2018 at 01:32:24PM +0100, Chris Wilson wrote:
> Quoting Imre Deak (2018-08-17 13:26:13)
> > After
> > commit 2cd9a689e97b ("Refactor intel_display_set_init_power() logic")
> > it makes more sense to check the power domain/well refcounts after
> > enabling the power domains functionality. Before that it's guaranteed
> > that most power wells (in the INIT domain) will have a reference held,
> > so not an interesting state.
> 
> Indeed, that is true. But it is also used to check that we do acquire
> the powerwells on init.

Yes, intel_power_domains_enable() is called both during init and system
resume, after HW readout and acquiring the needed power wells.

> I think it would sensible to include a verify state at the end of
> power_domains_init_hw, or do you think the sync_hw makes that
> superfluous?

We have all power wells in the INIT domain enabled there, so I thought
it's less interesting, but yes I can also add the check to init_hw,
fini_hw, enable/disable and suspend/resume steps.

--Imre