From: Benjamin Herrenschmidt <benh@kernel.crashing.org>

> My screen is still a bit garbeld after booting.
> Still like http://zodiac.dnsalias.org/images/garbage.jpg

Yes, usual boot-time x86 garbage. Well, let's imagine it's as simple
as clearing the framebuffer during boot :) Try this patch and let me
know. If that doesn't help, then the problem is definitely in fbcon.