|This page describes how to produce a CD-ROM (or DVD, for that matter) which can boot Darwin on both EFI- and BIOS-based systems.
Master a CD from which both EFI- (Intel Mac) and BIOS-based (PC) systems can boot.
An Intel-based Macintosh will actually be able to boot the volume either through EFI (right-hand side) or through its Compatibility Support Module ("Boot Camp") BIOS emulation (left-hand side, misleadingly labeled "Windows").
The key is to use a HFS+ filesystem for the image (thus, making a ".dmg" rather than a ".iso") and "injecting" parts of an El Torito ISO into it, This is called a "hybrid image".
To create a hybrid image, you can use the pd_makedmg script. It is based on darwinmaster.sh, and has been extended to support EFI booting in addition to BIOS booting. Its syntax is as follows:
pd_makedmg /Volumes/PureDarwinDisk /tmp/puredarwin.dmg PureDarwin
This would take the files located at /Volumes/PureDarwinDisk (which should contain a working Darwin installation) and turn them into a disk image located at /tmp/puredarwin.dmg with the name of "PureDarwin", which could be burned to a CD e.g., using Disk Utility.
Note that pd_makedmg currently needs a Mac to run, since it makes use of commands like hdiutil which are not part of Darwin.
Here is what it essentially does:
Following the instructions from above should produce a CD that boots at least to the point "Still waiting for root device...". For the kernel to be able to access the CD, the necessary kexts need to be installed of course. These are, in addition to the minimal set of kexts: