I wanted to start a new thread to deal with Grub/Grub2 on PowerPC systems.
First, a little news, Apple PPC systems that support GPT disks do support booting ELF binaries off a FAT32 partition on a GPT Disk. Not huge news, but it will allow use to boot off a GUID disk and keep our bootloader on the FAT32 partition.
I suppose that we could setup a GPT disk and load an ELF binary of an HFS+ partition, but I'd just rather maintain some continuity with EFI/UEFI systems as far as bootloaders being on the FAT32 partition.
As we know GPT disks should support drives larger than 2.2TB, but I don't have any of those disks to test with OF/PPC.
As this pertains to GRUB/GRUB2 we can build binaries larger than 800k( for those that don't know, the 800k limitation of an APPLE_BOOT HFS partition is a holdover from 800k floppy drives ).
As to why we still need to use these 800k partitions to boot other OS's is a mystery to me, but Open Firmware and Apples Boot Selector will look for a bootable :tbxi on the APPLE_BOOT partition, so we've always used it on New World Mac's.
I doubt Apple's Boot Selector will see an ELF binary on any partition as blessed, only a :tbxi resource, but I haven't tested.
Overcoming the 800k limitation is important if, like me, we want to load up Grub/Grub2 with modules.
As an aside, I don't see an i2c module, but it shouldn't be too hard to port one. I'd like to use Grub/Grub2 to poke around the I2C bus on my G5's to see if, maybe, I can find a programmable PLL and overclock the G5. Perhaps @dosdude1 or @LightBulbFun could offer some insight there.
Ok, time for a little Q & A;
Could someone offer some guidance as to setting up a bootable grub.cfg on PPC?
I can't for the life of me boot from Grub.
I have a Linux Ext4 partion with my /boot and /home file systems on partition 3 of my first SATA drive, but even tho I give the UUID of the partiton in my grub.cfg, I still just end up at the Grub Command Line.
First, a little news, Apple PPC systems that support GPT disks do support booting ELF binaries off a FAT32 partition on a GPT Disk. Not huge news, but it will allow use to boot off a GUID disk and keep our bootloader on the FAT32 partition.
I suppose that we could setup a GPT disk and load an ELF binary of an HFS+ partition, but I'd just rather maintain some continuity with EFI/UEFI systems as far as bootloaders being on the FAT32 partition.
As we know GPT disks should support drives larger than 2.2TB, but I don't have any of those disks to test with OF/PPC.
As this pertains to GRUB/GRUB2 we can build binaries larger than 800k( for those that don't know, the 800k limitation of an APPLE_BOOT HFS partition is a holdover from 800k floppy drives ).
As to why we still need to use these 800k partitions to boot other OS's is a mystery to me, but Open Firmware and Apples Boot Selector will look for a bootable :tbxi on the APPLE_BOOT partition, so we've always used it on New World Mac's.
I doubt Apple's Boot Selector will see an ELF binary on any partition as blessed, only a :tbxi resource, but I haven't tested.
Overcoming the 800k limitation is important if, like me, we want to load up Grub/Grub2 with modules.
As an aside, I don't see an i2c module, but it shouldn't be too hard to port one. I'd like to use Grub/Grub2 to poke around the I2C bus on my G5's to see if, maybe, I can find a programmable PLL and overclock the G5. Perhaps @dosdude1 or @LightBulbFun could offer some insight there.
Ok, time for a little Q & A;
Could someone offer some guidance as to setting up a bootable grub.cfg on PPC?
I can't for the life of me boot from Grub.
I have a Linux Ext4 partion with my /boot and /home file systems on partition 3 of my first SATA drive, but even tho I give the UUID of the partiton in my grub.cfg, I still just end up at the Grub Command Line.
Code:
search --no-floppy --fs-uuid --set=root 5a61aaaa-bb3a-4b3b-9590-9662366079e5
set prefix=($root)/boot/grub