Dual head on ATI FirePro M5800

[Ole Tange]

On Tue, Oct 5, 2010 at 1:37 AM, Alex Deucher <alexdeucher at gmail.com> wrote:
> On Mon, Oct 4, 2010 at 5:37 PM, Ole Tange <ole at tange.dk> wrote:
>> I am trying to get dual head on ATI FirePro M5800 working. LVDS works,
>> but VGA-0 is in power save mode no matter what I do.
>>
>> My colleague got the non-free driver working, but I would prefer using
>> the free driver. My research seems to indicate the chipset is called
>> Redwood or r8xx or RV830 or r800 or Evergreen - but I could be wrong.
>>
>> I have been unable to find a guide for this card and the obvious
>> (xrandr --output LVDS --output VGA-0 --left-of LVDS) does not work.
>> Neither does KDE's gui config of display.
>>
>> Below is some output that may help.
>
> If you are not already, your best bet is to use KMS.  Some evergreen
> vbioses had a bug in the i2c table for the VGA port.  Make sure your
> kernel has this patch:
> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=ea39302b87b8d944d567ef29c0647c09da5743fa
> or better yet, try 2.6.36.

Now I have upgraded the Linux kernel to 2.6.36. I can now make the
VGA-0 go from powersave to an odd shade of greenish gray if I use
KDE's systemsettings to change the screen. I could not replicate that
using xrandr, though.

So it seems I am still stuck with one screen if I want to use the free driver.

Ideas?


/Ole