On 25 Apr 2021, at 18:01, James Madgwick wrote:
Ultimately I don't think being forced to use fbdev
really matters, these old GPUs have nothing to offer beyond 3D
acceleration - which has little application on this system in 2021. It
would however be interesting to see if this radeon slowness is
replicated on x86.
I’m using a Radeon HD 6570 now in a PowerMac11,2 and it works quite
well - it is as fast as I’d expect it to be from a machine of this
age. The PowerMac11,2 already has got PCIe (1.00) of course, so I
don’t know if it is specific to your machine’s architecture.
I’m experiencing the same issues with epiphany-browser as well though
(it’s quite fast, but colors are not ok), it does not work using
Wayland at all (only grey noise for the whole window). So this seems to
be specific to the ppc(64?) architecture.
I suppose the issues I’m experiencing (if not BigEndian errors) might
derive from the same source as the issues mentioned over there:
„X kinda works with the wsfb driver. Colours are all wrong because for
some reason the OF calls for colour map control don't work. Mine's got
a Radeon X1950, which the radeon driver of course supports, but for
some reason expects to find an x86 BIOS ROM with, which of course
doesn't exist on a mac. May or may not be easy to fix.“[1]
But I did not debug those yet.
I've also now created a new problem for myself. My system has two
disks,
one with MacOS and now one with Debian. I had disconnected the MacOS
disk while I installed Debian. After completing the installation, the
G5
would boot into Debian only if the Mac disk was unplugged. My mistake
was to then go into the startup disk utility on MacOS and see if I
could make Debian the startup disk. This didn't work and with the Mac
disk unplugged I now get the flashing "?" folder (I can still boot
manually from OpenFirmware). I guess MacOS has erased an nvram
variable
set by the Debian installer? Is there an easy way to reproduce what
the
installer did and get Debian booting automatically again?
You probably need to boot the install CD/image, mount your Debian root
and boot partitions, chroot into it and reinstall grub.[2] The device
IDs probably have changed by inserting the new drive. So, yes, it would
have been better to do the install with all disks inserted, I think.
Good luck
Johannes
[1] https://mail-index.netbsd.org/port-macppc/2017/10/01/msg002461.html
[2] Information about grub on PowerPC:
https://wiki.gentoo.org/wiki/GRUB_on_Open_Firmware_(PowerPC)
