Re: Creating a bootable CD for RS/6000

["Leigh Brown" <leigh@solinno.co.uk>]

Germán Poó Caamaño said:
> May someone give me some pointer to create a bootable CD for
> RS/6000 (CHRP64)?
>
> I'm not pretty sure that instructions shown at
> http://lists.penguinppc.org/yaboot-users/2002/yaboot-users-200212/msg00002.html
> can be applied for a RS/6000 (but I'll try it right now),
> because of the filesystems.
>
> I'll appreciate any pointer.

CHRP booting is described here:

http://playground.sun.com/1275/bindings/chrp/chrp1_7a.ps

Using the above, the procedure is:

1. Create a directory called ./ppc below the root of the CD-ROM tree.

2. Create a file called bootinfo.txt in the directory with the following
contents:

-------8<-------
<chrp-boot>
<description>Debian/GNU Linux Installation</description>
<os-name>Debian/GNU Linux</os-name>
<boot-script>boot &device;:\ppc\chrp\yaboot</boot-script>
<icon size=64,64 color-space=3,3,2>
<bitmap>
FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF
(another 127 lines of "FF FF ...")
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
(another 127 lines of "00 00 ...")
</bitmap> </icon> </chrp-boot>
------->8-------

I believe that due to firmware issues the bitmap must always be
specified.  It's probably best not to get to inventive in the
formatting of bootinfo.txt.

4. Create a directory called ./ppc/chrp below the root of the CD-ROM
tree.

5. Copy the following files into ./ppc/chrp:

   a. A yaboot binary that has had the note section added;
   b. One or more kernel images;
   c. One or more initial ramdisks.

   NB These could be placed elsewhere, I suppose, and the yaboot.conf
   modified appropriately (see below).

6. Create a directory called ./etc below the root of the CD-ROM tree.

7. Copy an appropriate yaboot.conf into ./etc, e.g.:

-------8<-------
init-message = "\nWelcome to Debian/GNU Linux\nHit <TAB> for boot
options.\n\n"
timeout=6000
default=linux

image=ppc/chrp/vmlinux-2.4.22-powerpc
        label=linux
        initrd=ppc/chrp/ramdisk.image-2.4.22-powerpc.gz
        read-only
(further images as required)...
------->8-------

8. Having assembled the rest of the CD-ROM image, you can now run
mkisofs.  I have created a patch to cdrtools to allow a RS/6000
bootable image to be created:

http://www.solinno.co.uk/leigh/cdrtools-2.00.3-chrp-boot.diff

You then run the mkisofs command as normal, however you must specify
-chrp-boot and -U options in addition to your normal command.  The
-U option is required because the firmware expects filenames to match
Unix conventions, but doesn't understand Rock Ridge.

Having done the above, you should be able to automatically boot
from the created CD.

*NOTES*

1. This is from memory so expect a few coasters.

2. With the patch to mkisofs you should be able to create a CD-ROM
that boots on PReP, CHRP and Macintosh, although I've not tried
the latter.

3. If the auto-boot fails, you should try to manually boot (e.g.
boot cdrom:/ppc/chrp/yaboot) to see if the yaboot installation
was okay.

4. You could probably create a CD that booted a Linux kernel
directly, but it wouldn't be sufficiently flexible for general use,
IMO.

Let me know if you have any problems, or if any of the above doesn't
make sense.

Cheers,

Leigh.