[igt-dev] [Intel-gfx] [PATCH igt] igt/kms_frontbuffer_tracking: Wait for PSR to be disabled

[Chris Wilson]

Quoting Daniel Vetter (2018-02-20 15:44:38)
> On Tue, Feb 20, 2018 at 02:33:08PM +0000, Chris Wilson wrote:
> > PSR may not exit instantaneously, so while asserting that PSR is
> > disabled after an action, we may have to wait a short while. Currently
> > that wait is waiting for PSR to enabled and expecting to timeout; this
> > fails when we start the assertion with PSR already enabled. Fix the wait
> > to wait until PSR is disabled rather than timeout.
> > 
> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> 
> I guess that's the reply to my question about the earlier
> kms_frontbuffer_tracking patch?

Which, the -ENODEV? I thought I explained that was purely to cope with
the i915_fbc_info API for !HAS_FBC machines, as we are running
kms_frontbuffer_tracking across farm1 in idle time.
https://intel-gfx-ci.01.org/tree/drm-tip/kasan2.html
 
> Makes a bunch more sense to me.

There's the question of whether to apply this to
fbc_wait_until_disabled() as well, but I guess fbc behaves slightly
differently as we don't see the assert failure there.
-Chris