Re: Switching debian-installer CD images to GRUB

[John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>]

On 5/1/19 7:43 PM, Thomas Schmitt wrote:
> You need to enable HFS+ production (or maybe future HFS production)
> 
>           xorriso_push ("-hfsplus");
>           xorriso_push ("-apm-block-size");
>           xorriso_push ("2048");

Gotcha.

> The block size might be adjustable to 512, if a reason arises.
> File data start address granularity will be 2048, because of ISO 9660.

Ok.

> Type "tbxi" has not been used by grub-mkrescue yet. Googling ...
> It seems to be appropriate for BootX.
> 
> Did we have a link to this text already ?
>   https://opensource.apple.com/source/bless/bless-11/README.BOOTING
> It has a section  "== Old World booting from HFS+ ==".
> 
> Blessing "p" was not tested yet. You should use some Mac tool to
> verify that it gets correcty applied by libisofs.

Isn't the fact that my iBook G4 booted the grub-mkrescue image just
find proof enough?

> Is option
>   -sysid PPC
> really needed ?

No idea. But when I add it, xorriso actually complains.

> The old powerpc 6.0.5 and 8.0.0 netinst ISOs do not contain a BootX
> file or a /System/Library/CoreServices directory. 9.4.0-ppc64el does not
> either.
> 
> So i have to make it somewhat artificial on a x86 grub-mkrescue ISO,
> which has HFS+ for x86 Macs. I simulate the missing file BootX by a copy
> of the ISO's EFI image:
> 
>   mount /dvdbuffer/grub-mkrescue-original.iso /mnt/iso
> 
>   xorriso -as mkisofs \
>      -o test.iso \
>      -hfsplus \
>      -apm-block-size 2048 \
>      -hfsplus-file-creator-type chrp tbxi \
>                                 /System/Library/CoreServices/BootX \
>      -hfs-bless-by p /System/Library/CoreServices \
>      -sysid PPC \
>      -chrp-boot-part \
>      -graft-points \
>      /mnt/iso \
>      /System/Library/CoreServices/BootX=/mnt/iso/efi.img

Looking at the grub-mkrescue.c source, I figured the proper linking would be:

      xorriso_link ("/System/Library/CoreServices/grub.elf", "/boot/grub/powerpc-ieee1275/core.elf");
      xorriso_link ("/boot/grub/powerpc.elf", "/boot/grub/powerpc-ieee1275/core.elf");

> An ISO emerges.
I will give it a try, however with the matching that for the elf files as mkrescue
uses it. That's what works, after all.

Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer - glaubitz@debian.org
`. `'   Freie Universitaet Berlin - glaubitz@physik.fu-berlin.de
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