Requirements for Grub2 PPC install

[jon]

I'm sorry for posting to the list, but I've had some trouble tracking down
the answers I need..

I've tried following the instructions on the Wiki for installing grub2/ppc
on a clean, basic (working) Gentoo install with yaboot.  My partitions
were set up as:

p1: Apple partition map
p2: Apple bootloader
p3: 512MB Swap
p4: 40GB ext3 as /

When I tried to boot against it, I saw the initial Grub welcome message,
but it immediately gave an error message.  I don't have the error message
to show as I've rebuilt the machine with extra partitions this
time.  I can now try dedicating one for /boot and possibly one for grub
itself (running the grub-install seemed to insist on one).

My question isn't so much why my original try failed, but what are the
requirements for setting up grub2 on ppc's?  (req'd partitions,
filesystems, sizes, initrd? etc.)  I'd appreciate if someone could work
with me on setting this up offline.  Once I understand what is needed and
can get it reliably installed, I will happily update the documentation to
help the next guy (or gal).

Alternatively, is there a description of the layout of the grub2 code so I
can follow the process myself to figure it out?  I'm a developer, but I'm
having some difficulty figuring out the organization as I poke around.
Would the documentation for grub legacy help?  Is there some general
information floating around that I haven't found yet?

Thanks.. (and sorry again for the noob questions)

Jon