Trying to use Radeon driver on Apple eMac

Alex Deucher alexdeucher at
Mon Dec 8 23:24:43 PST 2008

On Tue, Dec 9, 2008 at 1:58 AM, Joseph Adams <joeyadams3.14159 at> wrote:
> I tried every single combination of ConnectorTable entry you
> suggested, but none of them seemed to have any effect.  However, I did
> try all the MacModel s.  I found that for every powerbook-* option,
> the screen would flash the correct image, then would go to black right
> away (when the server is started or VT-switched to).  The image looked
> fine on the bottom half, but the top half was covered in trash.

Can you attach a log from one of your attempts with the ConnectorTable
options I suggested?

> The flash I'm referring to shows the image at 1024x768, then goes to
> black in about a fifth of a second.  The image pulses in an expanding
> motion (this is a CRT monitor) then immediately blanks with no monitor
> glow.

The powerbook settings are certainly wrong for your system as it does
not use LVDS or TMDS.  It's going to be some combination of the
primary dac (probably the internal screen) and the tv dac (probably
the external connector) since both outputs are analog.

> I tried running glxgears in the few-millisecond interval, but that
> requires me killing it through SSH.  It displays the correct image,
> though.
> I took a screenshot with xwd, and the screenshot is fine.  The image
> is 1280x1024, and the GNOME panels line up to 1024x768.  The 1024x768
> is the resolution I see in that quick flash.

The framebuffer is set up fine, we need to sort out the the proper
display controller setup.

> In these attempts, I get the following xrandr output:
> Screen 0: minimum 320 x 200, current 1280 x 960, maximum 2048 x 1200
> LVDS connected 1024x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm
>   1024x768       60.0*+   60.0
>   800x600        60.3
>   640x480        59.9
> DVI-0 connected 1280x960+0+0 (normal left inverted right x axis y
> axis) 0mm x 0mm
>   1280x960       60.0*+   59.9
>   1024x768       60.0
>   800x600        60.3
>   640x480        59.9
> S-video disconnected (normal left inverted right x axis y axis)
> I still cannot change Xorg modes through xrandr due to the same error messages.
> I played around with the Radeon driver source by adding an eMac entry
> but essentially copying it from the PowerBook stuff.  I have made a
> rather makeshift patch against xf86-video-ati-6.9.0 which has some
> unneeded garbage in it (it can also be downloaded at
> ), but it might be
> helpful.  With that patch and with that driver, I get the flash effect
> described above without any special xorg.conf options, and my
> Xorg.0.log mentions eMac.

You'll want to start with the settings in my ConnectorTable option.

> My cat /proc/cpuinfo is:
> processor       : 0
> cpu             : 7455, altivec supported
> clock           : 999.999997MHz
> revision        : 0.3 (pvr 8001 0303)
> bogomips        : 66.04
> timebase        : 33179574
> platform        : PowerMac
> model           : PowerMac4,4
> machine         : PowerMac4,4
> motherboard     : PowerMac4,4 MacRISC2 MacRISC Power Macintosh
> detected as     : 80 (eMac)
> pmac flags      : 00000010
> L2 cache        : 256K unified
> pmac-generation : NewWorld
> (hehehe, not quite a gigahertz)
> Anyway, what might be causing the image to have garbage and to
> immediately disappear?  Thanks.

It's not actually working.  the flash is just a byproduct of using the
powerbook settings which are wrong for your setup.


> On Mon, Dec 8, 2008 at 6:22 PM, Alex Deucher <alexdeucher at> wrote:
>> On Mon, Dec 8, 2008 at 2:01 PM, Joseph Adams <joeyadams3.14159 at> wrote:
>>> I'm struggling to get the Radeon driver to work on my eMac G4's Radeon
>>> 7500 card (the fbdev driver works fine at 1024x768 with no
>>> acceleration).  On both Fedora 8 and Fedora 10 with default xorg.conf,
>>> the screen is blank (the CRT doesn't glow or anything).  I have a CRT
>>> monitor that supports up to 1280x960.  The eMac also has a video out
>>> port.  I suspect that video may show up on an external monitor, but I
>>> can't test that until my adapter arrives.
>> Mac cards don't have a connector table and are always wired up
>> strangely.  We'll probably need to add a custom connector table for
>> your card as it's currently falling back to the default which is
>> probably wrong for your card.  Can you send me the output of
>> /proc/cpuinfo?
>> Try the following option and let me know which combinations work:
>> Option "ConnectorTable" "i,1,0,1,j,2,0,1"
>> where i and j are one of the following:
>> 96, 100, 104, or 108
>> and i != j.
>> i and j specify the gpio line used for ddc, so when you get the right
>> combination, you should see the driver picking up an edid if your
>> monitor supports it.  If the built in monitor doesn't supply an edid,
>> we'll have to add a quirk for that as well.
>> Alex

More information about the xorg mailing list