Mac Pro (late 2013 model) EFI and iPXE booting

[kiwi66]

I have documented my work here:

http://www.fink.org/netboot/netbooting.html

it includes a script to build a NBI from the src directly.
Now I can boot from the network into IPXE , fetch my config via HTTP from my webserver and then load linux kernel and ramdisk.

There's a few things which don't work when trying to build IPXE on MacOS X, namely it uses clang and not gcc and that spills out some warnings as errors which then stop the compilation. But compiling it under Linux and using it on a Mac works just fine.