Problems with ati driver on Tibook

[John R. Dunning]

Hi driver maintainers.  My apologies for going straight to this list,
but I seem to have run out of options.

I have a titanium powerbook with a radeon ati mobility M6 LY
controller.  I'm running gentoo linux on it.  Everything worked fine
until I upgraded (due to having the disk fail) and now I can't seem to
get the video to work.  

The symptom is that when I startx, the screen flashes, I get a fixed
(nonblinking) cursor in the upper left corner, and the rest of the
screen does this sort of "bloom" of white, fading to black, starting
more or less in the center and spreading to the edges.  It looks like
the backlight is doing some funky, or something.

The system is not dead, if I kill X it unwinds and I'm back to the
character console.

I've turned up logging in X, and it spews lots of debug, but nothing
is jumping out at me.  I've tried a couple versions of the ati driver,
all did the same thing.

I wasn't sure what would be useful to provide as info.  

    alien ~ # equery l xorg-server          
    [ Searching for package 'xorg-server' in all categories among: ]
     * installed packages
    [I--] [  ] x11-base/xorg-server-1.6.3.901-r2 (0)
    alien ~ # equery l video-ati   
    [ Searching for package 'video-ati' in all categories among: ]
     * installed packages
    [I--] [ ~] x11-drivers/xf86-video-ati-6.11.0 (0)
    alien ~ # lspci
    0000:00:0b.0 Host bridge: Apple Computer Inc. UniNorth 1.5 AGP
    0000:00:10.0 VGA compatible controller: ATI Technologies Inc Radeon Mobility M6 LY
    0001:10:0b.0 Host bridge: Apple Computer Inc. UniNorth 1.5 PCI
    0001:10:17.0 Class ff00: Apple Computer Inc. KeyLargo Mac I/O (rev 03)
    0001:10:18.0 USB Controller: Apple Computer Inc. KeyLargo USB
    0001:10:19.0 USB Controller: Apple Computer Inc. KeyLargo USB
    0001:10:1a.0 CardBus bridge: Texas Instruments PCI1410 PC card Cardbus Controller (rev 02)
    0002:24:0b.0 Host bridge: Apple Computer Inc. UniNorth 1.5 Internal PCI
    0002:24:0e.0 FireWire (IEEE 1394): Agere Systems FW323
    0002:24:0f.0 Ethernet controller: Apple Computer Inc. UniNorth GMAC (Sun GEM) (rev 01)

If it's useful I can provide x logs etc.

If there's a better place to ask this please redirect me.  I've tried
the gentoo ppc lists and gotten nothing useful.

Thanks in advance...