From mboxrd@z Thu Jan  1 00:00:00 1970
From: christian.gmeiner@gmail.com (Christian Gmeiner)
Date: Tue, 28 Jan 2014 09:29:17 +0100
Subject: imx-drm: screen flickering
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References: <CAH9NwWe673znThNPWRvOCyAU2o7M-oouHD7+1tyRcmWTeJ8YFw@mail.gmail.com>
Message-ID: <CAH9NwWfjsGbLiuY_cDOrUUQFpeSumVVkr-kV2BRAKtsRgGaYGw@mail.gmail.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

2014-01-28 Christian Gmeiner <christian.gmeiner@gmail.com>:
> Hi all.
>
> From time to time it happens that my LVDS display is flickering (look
> at scroll bar in the video).
> https://drive.google.com/file/d/0B_fznDimUHVubWtvVFlMTkdBbUU/edit?usp=sharing
>
> I really want to find the root cause of it, but I do not know where to
> start. I can trigger this
> sometimes after xscreensever "blanks" the screen and the screensafer
> gets disabled
> via user input.
>
> Any hints?

I forgot to add some details. I am using a 3.12.4 kernel with some a
some patches (dts, ..). As root filesystem
I am using debian 7 and this is how my xorg.conf looks like:

root at OT:/sys/kernel/debug# cat /etc/X11/xorg.conf
#
# DO NOT TOUCH - AUTOGENERATED FILE
#

Section "Device"
        Identifier      "Card0"
        Driver          "modesetting"

EndSection

Section "InputClass"
        Identifier      "keyboard layout"
        MatchIsKeyboard "on"
        MatchDevicePath "/dev/input/event*"
        Driver          "evdev"
        Option          "XkbLayout" "us"
EndSection


xscreensaver makes use of DPMS. So I think that the the problem could
be related to DPMS somehow.

greets
--
Christian Gmeiner, MSc