[Intel-gfx] [PATCH] drm/i915: Return early when pipes are not available

[Ville Syrjälä]

On Thu, Nov 09, 2017 at 01:11:05PM +0200, Mika Kahola wrote:
> On Thu, 2017-11-09 at 11:01 +0000, Chris Wilson wrote:
> > Quoting Mika Kahola (2017-11-09 10:49:52)
> > > 
> > > At least in Coffee Lake it happens that we start initiliazing audio
> > > when
> > > no display is connected. This was discovered by CI when running IGT
> > > test
> > > case
> > > 
> > > drv_module_reload --r basic-no-display
> > > 
> > > The issue here is that the 'intel_device_info_runtime_init()' sets
> > > num_pipes to 0 but before this happens the audio part has already
> > > started
> > > to initialize itself. Later on the num_pipes is updated to 0 in
> > > intel_device_info_runtime_init() and we hit that when audio part is
> > > digging
> > > out ELD. This causes a warning in dmesg. To fix this issue, let's
> > > check the
> > > number of available pipes when trying to read out ELD.
> > dev_info_runtime_init() is too late. It depends on mmio being enabled
> > to
> > probe the HW and nothing else; so move it to i915_driver_init_mmio()?
> Ok. I could try that. I was also thinking that is there a way to
> postpone audio initialization?

We probably shouldn't be registering the audio thing until we've
actually set up the outputs.

-- 
Ville Syrjälä
Intel OTC