Block storage device mapping for OpenFirmware accessibility

[Rob Ballantyne]

Hello,

  Out of curiosity and self education I’m trying to setup a dev environment 
where I can experiment with early boot stages on PPC/PPC64 machines.

  I started out trying to get my local filesystem mapped through via VFAT to a 
fat based filesystem (floppy or otherwise) to a OF device that I can use to 
load/execute boot code.  No luck.  

  I tried creating fat floppy filesystems (Mtools) also no luck.

  I also tried building iso images (using hdiutil, I’m using a Mac) without 
luck.

  There must be something fundamental I’m missing about how the details of the 
-drive directive work.  And there must be something about how I’m creating the 
ISO image (because I can attach a FreeBSD ppc ISO and see its filesystem as OF 
device “cd:,\”

  Is there an easy way to create/build an image (or directory—if VFAT can be 
made to work) that can be attached via command line options and have it visible 
as a source of files for booting the ppc/ppc64 emulated environment?

Thanks!

Rob