Behind The Driver

Installing Debian on a 2005 model PowerMac G5

26 Dec 2012

I have a 2005 model PowerMac G5. This is the later generation. It is distinguished from the earlier generation by the presence of PCIe instead of PCI-X and AGP. It also uses DDR2 memory instead of DDR and uses a Dual-Core G5 CPU instead of the Dual Single-Core CPUs found in the earlier models.

As it is too old to run any current versions of OSX ( it stops at 10.5 ) and it is not binary compatible with most of the OSX apps I use now, I decided to give it a new life running the latest version of Debian Linux 7.0 Wheezy. Wheezy is currently in the testing branch but it is very close to release in stable.

So naturally, I did what you would probably expect. I went to debian.org, downloaded the latest PowerPC ISO for testing ( wheezy at the time of writing ) and burned it to a blank DVD. Unfortunately I had forgotten that the G5 had a faulty ATA ( the hdds are sata, optical is ata ) DVD-RW drive. The next step was to take the FireWire DVD-RW drive I had and hook that up. Unfortunately at some point in its years of storage it has decided that it no longer likes to power on. The next step was to try out my USB 2.0 BD-ROM/DVD-RW drive. I was hesitant to try this option in the first place because I remember reading that PowerMac G5 machines don’t like to boot from USB.

Sure enough, the reports turned out to be true. This is how it appeared on the surface at least. Booting the machine while holding the ‘c’ key to try and make it load the installer from the CD ( or DVD ) drive did nothing. Reports ( lies, hearsay, and forum posts of questionable technical accuracy ) on the internet showed that the Macs running open firmware should be able to boot from USB, but the PowerMac G5 was the exception.

I decided to boot the machine into open firmware mode to investigate. This is really the first time I’ve booted a machine into open firmware to do anything other than marvel at its bare command prompt. I found several very useful guides online explaining some open firmware commands. ( here, here, here, and here )

At the prompt I entered ‘devailias’ and was informed that there were two distinct devices in the system for CD and USB disk. One was named ‘cd’ and the other ‘ud’. Determining which of those was the DVD-ROM and which was the USB Disk is left as an exercise to the reader.

After finding out the disk I was looking for was named ‘ud’, a helpful mailing list post informed me the command I want to use is ‘boot ud:,\\yaboot’. After a moment yaboot loaded and I was able to install debian from the USB DVD-ROM. I won’t go into the details of the process because after yaboot had loaded the debian installer everything worked as it would in a normal x86 debian install. The bootloader was automatically installed onto the G5 properly without any input from me. All of the hardware save the WiFi card appears to work. The WiFi card reports missing firmware.