Bug 26616

Summary:

[KMS] cannot find CRTC for LVDS; regression

Product:

xorg

Reporter:

Oldrich Jedlicka <oldium.pro>

Component:

Driver/Radeon

Assignee:

xf86-video-ati maintainers <xorg-driver-ati>

Status:

RESOLVED FIXED

QA Contact:

Xorg Project Team <xorg-team>

Severity:

major

Priority:

medium

Version:

git

Hardware:

x86 (IA32)

OS:

Linux (All)

Whiteboard:

i915 platform:

i915 features:

Attachments:

Description	Flags
Output from `dmesg`	none
Xorg.0.log	none
fix shared ddc detection	none
dmesg	none
Xorg.0.log	none

Description Oldrich Jedlicka 2010-02-17 12:31:47 UTC

Created attachment 33367 [details]
Output from `dmesg`

There is currently a regression in drm-radeon-testing branch of GIT kernel source. The problem was originally fixed in bug #25150.

Symptoms:

LVDS shows only horizontal stripes during boot and changes color to white. Monitor connected to DVI-0 runs well, X.org starts and runs on DVI-0 only. Running

  xrandr --output LVDS --auto

shows "cannot find crtc for LVDS", but running 

  xrandr --output DVI-0 --off
  xrandr --output HDMI-0 --off
  xrandr --output LVDS --auto
  xrandr --output DVI-0 --auto

shows the screen correctly. I've bisected the drm-radeon-testing branch and the first problematic commit is bcc1c2a1d22974215e39dc87ce746ba9a39223e5 "drm/radeon/kms: add initial Evergreen support (Radeon HD 5xxx)".

dmesg and Xorg.log attached.

Comment 1 Oldrich Jedlicka 2010-02-17 12:32:47 UTC

Created attachment 33368 [details]
Xorg.0.log

Comment 2 Oldrich Jedlicka 2010-02-17 12:34:52 UTC

I have ATI Mobility Radeon HD 3470, I'm running xorg-server 1.7.5, libdrm git, xf86-video-ati git, mesa git, kernel branch radeon-drm-testing (as shown above).

The problem can be seen from the first moments of kernel switching to graphics during boot.

Comment 3 Alex Deucher 2010-02-18 23:16:58 UTC

Created attachment 33410 [details] [review]
fix shared ddc detection

This should do the trick.

Comment 4 Oldrich Jedlicka 2010-02-21 14:48:02 UTC

(In reply to comment #3)
> Created an attachment (id=33410) [details]
> fix shared ddc detection
> 
> This should do the trick.

Yes, that does the trick. Works for me. dmesg and Xorg.0.log attached.

Comment 5 Oldrich Jedlicka 2010-02-21 14:49:04 UTC

Created attachment 33476 [details]
dmesg

Comment 6 Oldrich Jedlicka 2010-02-21 14:49:31 UTC

Created attachment 33477 [details]
Xorg.0.log

Comment 7 Alex Deucher 2010-02-21 14:56:02 UTC

Pushed upsteam.

Comment 8 Oldrich Jedlicka 2010-02-21 15:09:57 UTC

And thanks for quick response (as usual) :-)

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