On 05/29 2023 21:01 Stan Johnson wrote:
I don't know anything about Apple_Boot, but you are likely right that it is also hidden from Mac OS 9 and Mac OS X. It appears Apple_Bootstrap is used only by NewWorld PowerPC Macs. It's just an HFS-formatted partition that is type Apple_Bootstrap instead of Apple_HFS, so while it can be mounted manually by Mac OS X, it isn't accessible by default. And I don't think it shows up in the boot selector menu (option key at boot).
Apple_Boot, Apple_Bootstrap, Apple_HFS, Apple_HFSX... doesn't matter for the OS Picker to list it. Only the filesystem is important (HFS and HFS+ support blessing), and if there's a blessed CHRP boot script or not. All you need to add is a CHRP boot script to make it appear on the OS Picker screen. That's actually easy: no matter what your boot file is, it's probably blessed. So, find which file that is. As an example, this might be grub.bin. So, now simply create a text file of any filename (it really doesn't matter!) with the following content: <CHRP-BOOT> <COMPATIBLE> MacRISC MacRISC3 MacRISC4 </COMPATIBLE> <OS-NAME> Debian GNU/Linux </OS-NAME> <BOOT-SCRIPT> " screen" output load-base release-load-area boot &device;,grub.bin </BOOT-SCRIPT> </CHRP-BOOT> Now, simply bless the CHRP boot script filename instead of the original one (grub.bin in the example). The CHRP script loads whatever you specify, so in the example the original grub.bin... Next time you boot, hold the option key and you should now see "Debian GNU/Linux" (or whatever you wrote in the <OS-NAME> field) as one option (with no icon). The important part really is that the <COMPATIBLE> field matches the actual hardware -- if it doesn't, it won't be shown by the OS Picker. Look at https://wiki.gentoo.org/wiki/GRUB_on_Open_Firmware_(PowerPC) for an example with the GNU icon, and also how to bless the CHRP boot script.
The last time I installed Debian SID with GRUB on a PowerBook Pismo, the Apple_Bootstrap partition was mounted as /boot/grub (it might have been /boot, I don't remember now). But it was a persistent mount. Everything worked, except Mac OS and Mac OS X volumes could not be boot from the menu (booting Mac OS X also doesn't work on an Intel Core 2 Duo system).
Actually, I was able to boot Mac OS X from GRUB. But if I remember correctly, I had to play with it a bit as it isn't intuitive... os-prober might be helpful as a starting point.
Unfortunately, I don't have the programming skills to fix it. If anyone has found or developed working grub.cfg entries that allow booting of Mac OS X and Mac OS 9, please let me know, as I would prefer to use GRUB if I can. Also, if anyone has GRUB working on a PowerBook Lombard, please let me know (AFAIK, that's the only NewWorld PowerMac that doesn't work at all with GRUB; its Firmware version may be too old for something that GRUB is doing.)
The oldest hardware I own is a Clamshell, original 1999 edition without firewire. I have getting Debian installed on it on my "hobby to-do list", but haven't found the time yet. Linux User #330250
