install a smp kernel indeed.
sudo apt install linux-image-powerpc-smp
My PoweMac G5 has 4 processors that are not recognized and thus I've installed that smp kernel. However when booting immediately after the installation, and when choosing linux, I am greeted by a white screen stating something like:
Invalid memory access at SSR 00000000.00C304C SSR1 10000000.0008303c
Apple Mac PowerPC (blá blá)
Welcome to open firmware. To continue booting type "mac-boot" and press return.
To shut-down type "shut-down" and press return.
Release keys to continue!
The thing is that the keyboard is not even responsive. A forced shutdown and reboot with "X" option gets me into OSX without problems, but I can't seem to be able to enter mintPPC.
This happened just now that even BBC radio 4 streaming was working