Re: i915 wakes from suspend to RAM with blank screen after commit cd9dde44f47501394b9f0715b6a36a92aa74c0d0

[Lubos Kolouch <lubos.kolouch@gmail.com>]

Keith Packard, Sat, 21 Jan 2012 10:15:24 -0800:

> On Sat, 21 Jan 2012 10:32:14 +0000 (UTC), Lubos Kolouch
> <lubos.kolouch@gmail.com> wrote:
> 
>> I git bisected it to commit cd9dde44f47501394b9f0715b6a36a92aa74c0d0 is
>> the first bad commit commit cd9dde44f47501394b9f0715b6a36a92aa74c0d0
>> Author: Adam Jackson <ajax@redhat.com>
>> Date:   Fri Oct 14 12:43:49 2011 -0400
> 
> Did you try reverting this single commit on top of 3.3-rc1?
> 
> And, can you collect the dmesg output with the kernel parameter
> drm.debug=0xe added to the boot line, both messages at boot time *and*
> messages during resume would be needed. If it works at boot time, I'm
> quite surprised it somehow doesn't work at resume...

I tried now and when I revert this line :

- return (pixel_clock * bpp + 7) / 8;
+ return (pixel_clock * bpp + 9) / 10;

resume works OK for me with 3.3-rc1.

Before change (failed)
----------------------
dmesg after boot - http://paste.pocoo.org/show/538343/
dmesg after failed resume -  http://paste.pocoo.org/show/538344/

After change (OK)
-----------------
dmesg after boot - http://paste.pocoo.org/show/538345/
dmesg after OK resume - http://paste.pocoo.org/show/538346/

Luboš Kolouch