How to create the ecoff boot image:
-----------------------------------

tip22 <vmlinux> <initrd> <outputfile>

- vmlinux is an ELF Linux kernel. You currently need to apply an extra 
  patch for correct commandline parsing (see /usr/share/doc/tip22/examples)
- initrd is the gzip compressed initial ramdisk you want add
- outputfile is the ECOFF bootimage. You can for example tfpboot this image on
  an SGI Indy using the bootp(): command in the prom.

it basically works like this:
-----------------------------
- tftpload.o is a relocatable object created during package build time
- the tip22 script converts the ramdisk and vmlinux to ecoff relocatable objects
  using linker scripts including symbols that mark the beginning and end of
  kernel and ramdisk
- those are linked together into the output file using yet another linker script
- when executed by the prom the embedded loader:
   - memcopies the kernel to its loadaddress
   - memcopies the initrd after the kernel to a page boundary
   - parses the command line and everything within an append="..." statement is passed on
     to the kernel, e.g. 'bootp(): append="console=ttyS0"'
   - jumps into the kernel passing the start address and size of the initrd on the
     command line

 -- Thu,  15 May 2002 23:07:18 +0200 Guido Guenther <agx@sigxcpu.org>
