Comment # 25 on bug 1119621 from Takashi Iwai

(In reply to Tejas Guruswamy from comment #24)
> I finally had a chance to test again. Summary is unfortunately
> kernel-default-4.20.5-1.1.ge544b4e.x86_64 from home:tiwai did not fix my
> problem. i915.fastboot=1 still works though.

Thanks for testing.  That's what I was afraid of :-<
So apparently we're looking at multiple issues.

> Note that
> fastboot=Y appears to be the default in 4.20.6 and drm-tip.

Really?  I couldn't find anything that changed the default in the kernel
source.

In theory we can flip fastboot=y as default.  It's been disabled due to the
regression seen on a Chromebook with some funky firmware.
But it's no right "fix", and the option can be given easily via boot option,
let's try to track the right cause for now.