[Intel-gfx] [PATCH] drm/i915: Fix __intel_wait_for_register_fw to not sleep in atomic

[Daniel Vetter]

On Wed, May 10, 2017 at 05:06:38PM +0100, Chris Wilson wrote:
> On Wed, May 10, 2017 at 05:19:32PM +0200, Daniel Vetter wrote:
> > The unconditionally fallback to the blocking wait_for resulted in
> > impressive fireworks at boot-up on my snb here. Make sure if we set
> > the slow timeout to 0 that we never ever sleep. The tail of the
> > callchain was
> > 
> > intel_wait_for_register
> > -> __intel_wait_for_register_fw
> >   -> usleep_range
> >      -> BOOM
> > 
> > It blew up in intel_crt_detect load detection code on the
> > ADPA_CRT_HOTPLUG_FORCE_TRIGGER in the ADPA register.
> > 
> > v2: Shut up gcc.
> 
> u32 uninitialized_var(reg_value) ?

Polished to v3 and applied, thanks for your review.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch