Il giorno mar, 27/04/2010 alle 18.57 -0400, Alex Deucher ha scritto:
On Tue, Apr 27, 2010 at 6:24 PM, GhePeU ghepeu@virgilio.it wrote:
Il giorno mar, 27/04/2010 alle 18.11 -0400, Alex Deucher ha scritto:
On Tue, Apr 27, 2010 at 5:30 PM, GhePeU ghepeu@virgilio.it wrote:
Il giorno gio, 15/04/2010 alle 13.41 -0400, Alex Deucher ha scritto:
From 837feb147c531219c7315857a6f17e145af8f750 Mon Sep 17 00:00:00 2001
From: Alex Deucher alexdeucher@gmail.com Date: Thu, 15 Apr 2010 13:31:12 -0400 Subject: [PATCH] drm/radeon/kms: fix tv dac conflict resolver
Hi,
a few days ago I upgraded to the last 2.6.34 rc kernel and found that with KMS both the console and X were using a 800x600 resolution instead of my LCD display's native resolution of 1440x900 who was selected by default with 2.6.33 and previous kernels.
I tracked the problem to this patch, which causes the same issues also when manually applied to 2.6.33: apparently the kms radeon driver wrongly detects a TV connected to my card (I don't have one, only a LCD display connected to the DVI port) and forces the TV default resolution for all the outputs.
You issue is not related to the patch. What the patch does is allow you to use the digital part of DVI plus TV at the same time. The analog part of the DVI port and the TV share the same DAC so they can't be used at the same time. Prior to the patch, both the TV and DVI were detected as attached, but the TV was always disabled since it was wrongly seen as conflicting with the DVI.
Your issue is actually a matter of load detection for TV not always being reliable. I don't know what a proper fix would be. We could disable load detection for TV to avoid false positives, but that would prevent automatic detection of TV which does work in most cases.
Alex
With UMS however I don't have this problem, is the logic different?
Shouldn't the driver behavior with KMS be the same, in this case? At least there wouldn't be (apparent) regressions like the one I'm experiencing.
UMS does not enable load detection on TV by default while KMS does, the difference being KMS provides both the console and X so you want to make sure you put something up on whatever monitors or tvs happen to be attached. I'm not sure what the best answer is here.
Alex
Would it be possible to add a module option to disable tv load detection? As things are now I must always change back the resolution to 1440x900 and disable the TV.
By the way I just tested "radeon.tv=0" and both 2.6.33 and 2.6.34 rc5 fail with a "BUG: unable to handle kernel NULL pointer dereference". Syslog output attached.
Giacomo