radeon kms, LCD timing info

[Howard Chu]

Howard Chu wrote:
> Alex Deucher wrote:
>> On Sat, Oct 31, 2009 at 6:41 PM, Howard Chu<hyc at symas.com>  wrote:
>>> I have an HP dv5z laptop with HD3450 GPU. It came with a 1680x1050 LCD panel
>>> and I'm currently trying to use a 1920x1200 panel instead. The panel that I
>>> have seems to work fine as far as booting and text mode goes, but when I start
>>> up X I get a black screen. By the way, this is currently running Ubuntu Jaunty
>>> but with a self-compiled 2.6.32-rc4 kernel and X stuff from the xorg-edgers
>>> ppa, so fairly bleeding edge driver and mesa.
>>>
>>> Another interesting bit is that with the fbcon driver, the VTs also work fine,
>>> and I have 75 rows x 240 columns of text. So it appears that the radeon driver
>>> is using acceptable timing parameters at startup, but when the X server starts
>>> it switches to a set of timing parameters that don't work.
>>>
>>> First question: how do I find out what timing parameters are in use at boot,
>>> and what's in use by radeon+fbcon?
>>>
>>> Second question: how do I set the correct timing parameters while X is
>>> running? Just playing with modelines doesn't seem to be sufficient. X boots up
>>> with several modelines but most of them are defective. E.g., 1920x1080
>>> actually displays the desktop instead of just a black screen, but it is
>>> shifted right by about an inch, and has a cyclic fade-to-white going on. Many
>>> of the other modes do the same thing, and a few (like 640x480) just display black.
>>>
>>> Any help would be much appreciated, thanks.
>>
>> Please post your xorg log and dmesg output.  The driver gets the panel
>> timing information from a table in the bios.  With the new panel, the
>> driver is probably still getting the old timing from the vbios.
>
> Posted at
>    http://highlandsun.com/hyc/dmesg.txt
> and
>    http://highlandsun.com/hyc/Xorg.0.log
>
Another note - I normally have vga=6 on my kernel command line. With this set, 
I see a lot of black horizontal lines running through the text. If I remove 
this setting, the screen is usually pretty solid (in text mode). Still no luck 
on 1920x1200 in X; I see the screen paint for a second and then it goes black.

-- 
   -- Howard Chu
   CTO, Symas Corp.           http://www.symas.com
   Director, Highland Sun     http://highlandsun.com/hyc/
   Chief Architect, OpenLDAP  http://www.openldap.org/project/