The radeon drivers doesn't work with the iMac. The integrated screen gets dark (no backlight even). Xorg: xorg-server-1.7.7 Driver: x11-drivers/xf86-video-ati-6.13.2 Works fine with vesafb driver, but at reduced resolution only and slow. See detailed hardware info and logs attached. I am happy to help trying out patches and config options.
Created attachment 39023 [details] Xorg.0.log
Created attachment 39024 [details] hwinfo --vbe
Created attachment 39025 [details] xrandr output
Created attachment 39026 [details] lspci -nnv
Created attachment 39027 [details] dmesg
This is UMS, not KMS. I have tried KMS as well, but that crashes the kernel while loading the firmware blob.
Outdated information. Now using KMS but still black screen. Will open a new bug.
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