Creating bootable CD images for sparc64

[John Paul Adrian Glaubitz]

Hi!

I'm currently working on switching Debian's installation CDs for sparc
and sparc64 to use GRUB instead of SILO for booting from CD.

I have modified debian-installer to call grub-mkimage to generate an image
of the type sparc64-ieee1275-cdcore which generates a GRUB image for booting.
See [1] for a list of modifications that I have made so far (including patches).

What I don't know yet is how to actually boot this image. My understanding
is that one needs to inject the 512-byte long cdrom.img into a CD using
genisoimage or similar tools. But how does the initial boot loader know
where to find the GRUB image? Is that actually a fixed string for CD boot?
I could not find any reference for that in the GRUB sources.

I have briefly also analyzed the DVD image for Oracle Linux for SPARC [2]
but that one has both SILO and GRUB files in its boot directory, so
I have no idea what it actually uses.

Adrian

> [1] https://lists.debian.org/debian-sparc/2019/04/msg00036.html
> [2] https://mirrors.dotsrc.org/oracle-linux/OL6/U9/x86_64/

-- 
 .''`.  John Paul Adrian Glaubitz
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