lvds downclocking breaks on G45/thinkpad T500
Andres Freund
On 2.6.33-rc1 I noticed that the display of my T500 with a G45 reacts very
slowly (you can see the text appearing) and colors take a time to "solidify".
I.e. making a white terminal black takes some seconds.
After some bisecting and guessing I recognized that the problem showed up
after:
commit 18f9ed12f8c977e25d65a16af8e8d73f72417ba1
Author: Zhao Yakui <yakui...@intel.com>
Date: Fri Nov 20 03:24:16 2009 +0000
drm/i915: Enable LVDS downclock feature through EDID.
If more than one mode with the same resolution defined in EDID has different
refresh rate, it is thought that the downclock is found for LVDS.
We will program the different FPx0/1 register so that we can select
dynamically
between the low and high frequency.
On the g4x platform we will use the CxSR feature to switch the different
refresh rate if the LVDS downclock feature is supported.
Signed-off-by: Zhao Yakui <yakui...@intel.com>
Reviewed-by: Jesse Barnes <jba...@virtuousgeek.org>
Signed-off-by: Eric Anholt <er...@anholt.net>
Setting dev_priv->lvds_downclock_avail = 0 in intel_find_lvds_downclock()
unsurprisingly avoids the issue.
Anything I can do to help analyzing the issue?
Andres
Andres Freund
> On 2.6.33-rc1 I noticed that the display of my T500 with a G45 reacts very
> slowly (you can see the text appearing) and colors take a time to
> "solidify". I.e. making a white terminal black takes some seconds.
> Anything I can do to help analyzing the issue?
a bit).
The missing config is attached now as well.
Andres
ykzhao
It will be great if you can open a new bug on
bugs.freedesktop.org(Product=xorg, component = driver/intel) and attach
the following info:
1. add the boot option of "drm.debug=0x06" and attach the output of
dmesg.
2. attach the output of "xrandr -q --verbose"
3. attach the vbios.dump, which can be obtained by using the
following command:
echo 1 > /sys/devices/pci0000:00/0000:00:02.0/rom
cat /sys/devices/pci0000:00/0000:00:02.0/rom
4. attach the output of Xorg.0.log
Thanks.
Yakui.
>
> Andres
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Andres Freund
> On Sun, 2009-12-27 at 01:41 +0800, Andres Freund wrote:
> > On Saturday 26 December 2009 17:49:29 Andres Freund wrote:
> > > On 2.6.33-rc1 I noticed that the display of my T500 with a G45 reacts
> > > very slowly (you can see the text appearing) and colors take a time to
> > > "solidify". I.e. making a white terminal black takes some seconds. ...
> > > Anything I can do to help analyzing the issue?
> >
> > Thats with recent git checkouts of xorg btw, if thats relevant (which I
> > doubt a bit).
> >
> > The missing config is attached now as well.
>
> It will be great if you can open a new bug on
> bugs.freedesktop.org(Product=xorg, component = driver/intel) and attach
> the following info:
> 1. add the boot option of "drm.debug=0x06" and attach the output of
> dmesg.
> 2. attach the output of "xrandr -q --verbose"
> 3. attach the vbios.dump, which can be obtained by using the
> following command:
> echo 1 > /sys/devices/pci0000:00/0000:00:02.0/rom
> cat /sys/devices/pci0000:00/0000:00:02.0/rom
> 4. attach the output of Xorg.0.log
ykzhao
> On Sunday 27 December 2009 14:10:55 ykzhao wrote:
> > On Sun, 2009-12-27 at 01:41 +0800, Andres Freund wrote:
> > > On Saturday 26 December 2009 17:49:29 Andres Freund wrote:
> > > > On 2.6.33-rc1 I noticed that the display of my T500 with a G45 reacts
> > > > very slowly (you can see the text appearing) and colors take a time to
> > > > "solidify". I.e. making a white terminal black takes some seconds. ...
> > > > Anything I can do to help analyzing the issue?
> > >
> > > Thats with recent git checkouts of xorg btw, if thats relevant (which I
> > > doubt a bit).
> > >
> > > The missing config is attached now as well.
> >
> > It will be great if you can open a new bug on
> > bugs.freedesktop.org(Product=xorg, component = driver/intel) and attach
> > the following info:
> > 1. add the boot option of "drm.debug=0x06" and attach the output of
> > dmesg.
> > 2. attach the output of "xrandr -q --verbose"
> > 3. attach the vbios.dump, which can be obtained by using the
> > following command:
> > echo 1 > /sys/devices/pci0000:00/0000:00:02.0/rom
> > cat /sys/devices/pci0000:00/0000:00:02.0/rom
> > 4. attach the output of Xorg.0.log
> Is it relevant whether I boot a kernel with the patch really enabled?
I don't know whether it is relevant with my patch. In fact my patch only
checks whether the LVDS downclock is found and then set the
corresponding flag.
Anyway, please open a new bug and I will investigate it.
thanks.
Yakui
Andres Freund
> On Sun, 2009-12-27 at 22:18 +0800, Andres Freund wrote:
> > On Sunday 27 December 2009 14:10:55 ykzhao wrote:
> > > On Sun, 2009-12-27 at 01:41 +0800, Andres Freund wrote:
> > > > On Saturday 26 December 2009 17:49:29 Andres Freund wrote:
> > > > > On 2.6.33-rc1 I noticed that the display of my T500 with a G45
> > > > > reacts very slowly (you can see the text appearing) and colors take
> > > > > a time to "solidify". I.e. making a white terminal black takes some
> > > > > seconds. ... Anything I can do to help analyzing the issue?
> > > >
> > > > Thats with recent git checkouts of xorg btw, if thats relevant (which
> > > > I doubt a bit).
> > > >
> > > > The missing config is attached now as well.
> > >
> > > It will be great if you can open a new bug on
> > > bugs.freedesktop.org(Product=xorg, component = driver/intel) and attach
> > > the following info:
> > > 1. add the boot option of "drm.debug=0x06" and attach the output of
> > > dmesg.
> > > 2. attach the output of "xrandr -q --verbose"
> > > 3. attach the vbios.dump, which can be obtained by using the
> > > following command:
> > > echo 1 > /sys/devices/pci0000:00/0000:00:02.0/rom
> > > cat /sys/devices/pci0000:00/0000:00:02.0/rom
> > > 4. attach the output of Xorg.0.log