Apple PowerPC computers always need `radeon.agpmode=-1` as default
|Reporter||A. Wilcox (awilfox)|
|Assignee||Horst Burkhardt (mc68030)|
|Reported||2018-02-01 12:06:29 -0600|
|Modified||2019-09-28 13:29:25 -0500|
|Hardware||Adélie Linux / PowerPC (32-bit)|
|Importance||Normal / normal|
AGP acceleration in the Radeon KMS driver has been broken on Apple PPC since the 2.6 series, and most developers are in agreement that since UniNorth is underdocumented, it probably won't ever be fixed.
We need a way to add
radeon.agpmode=-1 to the kernel command line automatically on Apple computers. I am not sure if any non-Apple PowerPC machines ever shipped with AGP slots. Almost certainly any newer PPC systems are using PCI-e (even the Apple G5). I am thinking that we could add something to the GRUB 2 configuration system that determines if the machine is Apple (perhaps looking for Platform: PowerMac in /proc/cpuinfo) and then conditionally add it there. I am not sure of the feasibility of this.