OpenFirmware Resources

Booting Linux

In order to boot a PPC image of Linux

From CD

1. Power on the Mac and immediately press and hold C.
2. Alternatively, press and hold Command + Option + Shift + Delete. This will bypass the internal HDD and instead opt for a CD, external HDD, or (occasionally) a USB drive.
3. Finally, you can also press and hold Option, which will present you with a graphical list of bootable devices connected the Mac (if any).

From USB

• First, try bringing up the graphical boot selection screen (press and hold Option while booting). If you don't see an option for the USB drive (you likely won't), then...
• Boot into OpenFirmware (press and hold Command + Option + O + F). You will be presented with a white screen and a command prompt that will looks something like this:

  ok
 0 > _

To confirm your USB drive is recognized, type:

 0 > dev usb1 ls
  ok
 0 > dev usb0 ls
 ffa03650: /disk@1
  ok

The second command returns a disk ID, showing that the system recognizes the USB drive. Note that each individual port on the mac is ennumerated as usb0, usb1, etc. Type the following to boot to USB:

 boot usb0/disk:2,\\yaboot

This will drop you to a black screen with a command prompt (yaboot). Type install and you will then be able to follow through with the rest of the installation.

Resources

http://mac.linux.be/content/guide-open-firmware-apple-bios-0

http://www.firmworks.com/QuickRef.html