Peach Pi/Pit boot failures in linux-next (was Re: [RFC PATCH 1/1] drm/exynos: Move platform drivers registration to module init)

[Javier Martinez Canillas <javier.martinez@collabora.co.uk>]

[adding Kukjin as cc and dropping dri-devel]

Hello Kevin,

On 11/20/2014 07:22 PM, Kevin Hilman wrote:
>> My kernel command line is almost the same with the difference that
>> I'm using clk_ignore_unused and I just checked that not passing
>> that parameter, makes linux-next to hang showing the same output
>> log that Kevin reported.
> 
> Ah!  Good find.  I confirm that adding clk_ignore_unused is getting
> me booting again, but of course that is just masking a problem, so I
> hope someone can shed light on which clock isn't being correctly
> managed.
> 

True, I'm renaming the thread subject to track these issues separately
of the original Exynos DRM bug since these are unrelated.

So, I see two different boot failures on the Peach Pi[t] Chromebooks:

1) next20141121 boot fails due snd-soc-snow

Disabling CONFIG_SND_SOC_SNOW makes the boot to got a little further
but still fails with the second issue:

2) next20141121 boot hangs if unused clocks are disabled.

I tried to root cause these two issues but didn't see anything evident
so I'll find a last known good commit and bisect. If anyone has an
idea of the possible causes for these issues that would be appreciated.
 
> Might I also suggest that folks have their default command-line to
> *not* use clk_ignore_unused, since it's primary job is to workaround
> clock bugs.
> 

Agreed, I disabled now as well to catch regressions early. I carried
those parameters from Snow since I needed clk_ignore_unused to have
simplefb working on that machine.

> Kevin
> 

Best regards,
Javier