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Booting a GUID disk on PowerPC Macs
- Thread starter LightBulbFun
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I Just made a very cool discovery while playing around in OpenFirmware on my G5 Quad that I think is worth sharing
which is that its OpenFirmware implementation can read disks with GUID partition schemes!
after discovering this I quickly cloned Leopard onto a GUID disk and I was able to boot from it(so much for people saying PowerPC macs can only boot from Apple partition Map!
this is very good news especially for anyone who has a larger then 2.2TB drive that they wish to use in their PowerPC Mac as their startup disk (as APM only works properly with drives bellow 2.2TB)
however I suspect that this functionality is only available on the very last (Late?) 2005 PowerPC Macs, ill be testing more of my PPC systems for GUID boot-ability and updating this thread as I do
For some reason doesn’t seem to work on my Quad. Neither System preferences recognize a GUID-partitioned FW drive as bootable nor Open Firmware.
Disk is readable without issues, but is not seen as bootable.
By chance, have you tested this GUID-partitioned internally via one of the two SATA connections?
I’ve not tried booting a GUID-partitioned disk from an external enclosure on the late 2005 PowerBooks/iBooks — only when the drive was on the internal bus. (Ultimately, after learning that GUID/GPT could boot on those, I ran into a couple of annoying snags along the way — enough to warrant just reformatting with an APM scheme and sticking with that.)
I know for sure system preferences will not show it as bootable
I cant recall if the OpenFirmware boot picker did or did not, but its certainly is bootable if you manually do so in OpenFirmware
but first of all make sure you do have Leopard 10.5.8 on that drive
(and that it is indeed bootable on say an intel mac or such)but first of all make sure you do have Leopard 10.5.8 on that drive
Ah so it won’t work with 10.6 PPC?
What's the problem, guys? Didn't test GPT with FireWire disk (just don't have such boxes). In theory it have to boot like any other drive. What OF says ? (BTW I didn't use System Prefernces for boot switching because it works only for MAc OS versions, never seen it detects Linux drives ).
Didn't test GPT with FireWire disk (just don't have such boxes). In theory it have to boot like any other drive. What OF says ? (BTW I didn't use System Prefernces for boot switching because it works only for MAc OS versions, never seen it detects Linux drives ).It does, I have 10.6, 10.4.11 and 3 Linux distros on the same hard drive, formatted to gpt
Booting from gpt allows OpenSuse Tumbleweed to be installed on PM G5s. The way to go about it using an empty drive in the top bay:
1) Format your empty drive using the GUID partition scheme
2) Install OpenSuse Tumbleweed ppc64, let the installer use the entire drive, it should result in /dev/sda1 PreP, /dev/sda2 root, /dev/sda3 swap (the installer might complain about not being able to install grub). The installation won't be able to boot as the prep partition is not formatted as HFS and won't be seen by OpenFirmware on bootup
3) Reboot using a liveCD e.g. Adelie Linux, type c to access the grub command line
4) Type the following:
(adjust ultra0 and sda to which hard disk, 0/a is top, 1/b is bottom on the G5; also adjust sda2/gpt2 to your root partition)
5) This should boot you into opensuse
6) You might need to adjust the grub command line to suit your hardware, to do so go to Yast/boot loader and edit the default append. I have edited mine to work with a Radeon HD 5770:
7) If /boot/grub2/grub.cfg is already present, you can skip this step. If not, then go to Yast/Boot Loader and save the configuration. If /boot/grub2/grub.cfg is still not there, then you need to fully install grub, not just the yast bootloader frontend. In terminal type:
8) You will need to create a CHRP file called ofboot.b. This file will be allow your boot partition to be selectable in the startup menu (holding down Option). The file also contains a badge icon. A template can be downloaded here:
wiki.gentoo.org
(look for ofboot.b)
Type:
(paste the file contents)
Edit the openfirmware boot line
to suit your needs, e.g:
save (Ctrl-O)
9) You now need to make your prep partition bootable to openfirmware. You need to adjust /dev/sda1 if this is not your PreP partition.
You should have openSuse up and running and selectable in the boot menu.
If you want to set it as the default boot device, you will need to run
(adjust 0:1 to your drive : PreP-partition)
OpenSuse is pretty snappy on the PM G5 quad and, frankly, visually quite impressive. OpenGL and OpenCL work fine, there is out-of-the-box support for Radeon HD cards AND unlike under Ubuntu and Debian, Gnome/Wayland is fully supported on the GF7800 GTX (only flashback works with the latter under those). If you do end up using the GF7800 GTX change your grub append to:
EDIT: for now don't update to kernel 5.15.8, acpi doesn't seem to work all the time anymore, but you can stick to 5.12.X
Cheers,
And thanks to @LightBulbFun, @mansley12 and @LuigiBurdo whose posts got me to get this to work
1) Format your empty drive using the GUID partition scheme
2) Install OpenSuse Tumbleweed ppc64, let the installer use the entire drive, it should result in /dev/sda1 PreP, /dev/sda2 root, /dev/sda3 swap (the installer might complain about not being able to install grub). The installation won't be able to boot as the prep partition is not formatted as HFS and won't be seen by OpenFirmware on bootup
3) Reboot using a liveCD e.g. Adelie Linux, type c to access the grub command line
4) Type the following:
Code:
root=(ieee1275/ultra0,gpt2)
linux /boot/vmlinuz root=/dev/sda2
initrd /boot/initrd
boot5) This should boot you into opensuse
6) You might need to adjust the grub command line to suit your hardware, to do so go to Yast/boot loader and edit the default append. I have edited mine to work with a Radeon HD 5770:
Code:
video=offb:off video=nouveaufb:off video=radeonfb:off radeon.modeset=1 radeon.dpm=1 radeon.agpmode=-1 pci=realloc nouveau.modeset=0 quiet acpi=force loglevel=0 splash7) If /boot/grub2/grub.cfg is already present, you can skip this step. If not, then go to Yast/Boot Loader and save the configuration. If /boot/grub2/grub.cfg is still not there, then you need to fully install grub, not just the yast bootloader frontend. In terminal type:
Code:
sudo zypper install grub2
sudo grub2-install
sudo grub2-mkconfig -o /boot/grub2/grub.cfg8) You will need to create a CHRP file called ofboot.b. This file will be allow your boot partition to be selectable in the startup menu (holding down Option). The file also contains a badge icon. A template can be downloaded here:
GRUB on Open Firmware (PowerPC) - Gentoo wiki
Type:
Code:
nano ~/ofboot.bEdit the openfirmware boot line
Code:
boot hd:3,\grub\grub.img
Code:
boot ultra0:1,grubsave (Ctrl-O)
9) You now need to make your prep partition bootable to openfirmware. You need to adjust /dev/sda1 if this is not your PreP partition.
Code:
sudo zypper install hfsutils
#(be sure that this is your PreP partition, adjust otherwisde)
sudo hformat /dev/sda1
sudo hmount /dev/sda1
sudo hcopy /boot/grub2/grub :grub
sudo hcopy /boot/grub2/grub.cfg :grub.cfg
sudo hcopy ~/ofboot.b :ofboot.b
sudo hattrib -t tbxi :ofboot.b
sudo hattrib -b :
sudo humountYou should have openSuse up and running and selectable in the boot menu.
If you want to set it as the default boot device, you will need to run
Code:
nvram --update-config boot-device='first-boot/@0:1,\\:tbxi'(adjust 0:1 to your drive : PreP-partition)
OpenSuse is pretty snappy on the PM G5 quad and, frankly, visually quite impressive. OpenGL and OpenCL work fine, there is out-of-the-box support for Radeon HD cards AND unlike under Ubuntu and Debian, Gnome/Wayland is fully supported on the GF7800 GTX (only flashback works with the latter under those). If you do end up using the GF7800 GTX change your grub append to:
Code:
video=offb:off video=nouveaufb:off video=radeonfb:off nouveau.modeset=1 nouveau.config=NvMSI=0 radeon.modeset=0 quiet acpi=force loglevel=0 splashEDIT: for now don't update to kernel 5.15.8, acpi doesn't seem to work all the time anymore, but you can stick to 5.12.X
Cheers,
And thanks to @LightBulbFun, @mansley12 and @LuigiBurdo whose posts got me to get this to work
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Last edited:
Internal, bottom drive, will take a screenshot from diskutil and post it later on today.
It should work as an external install mind you, haven't tried that yet but if I remember correctly I did manage to boot gpt formatted usb drives
Last edited:
There you go
Attachments
Awesome, thanks.
I am waiting for a second SSD to arrive, once it does, I will try partitioning it to GUID, and hopefully I can make it bootable on the Quad.
P. S. Is that 10A190?
Yes it is, it's currently sitting on a 40Gb partition; to get it to work I had to restore it to an 80Gb partition (on the GUID-partitioned drive), and then shrink down it to 40Gb as somehow restoring it directly to the 40Gb image didn't work (the image was a backup of mine from 10A190, it could well be that I had files fragmented past the 40Gb mark). In any case restoring to a 80Gb partition on a GUID drive should work straight out of the box for you, hopefully!
Cheers,
Note that this only applies as-is to Quad G5s and possibly DC G5s and iMacs G5 iSight. For other machines, you will need to clone your partitions onto an Apple-partitioned drive as those models do not support booting from GPT. Thus untested on those other machines, but in theory the above-mentioned instructions should work after cloning the PReP and root partitions onto an Apple-partitioned drive. Obviously, your machine needs to support ppc64 for the current versions of Tumbleweed!Booting from gpt allows OpenSuse Tumbleweed to be installed on PM G5s. The way to go about it using an empty drive in the top bay:
1) Format your empty drive using the GUID partition scheme
2) Install OpenSuse Tumbleweed ppc64, let the installer use the entire drive, it should result in /dev/sda1 PreP, /dev/sda2 root, /dev/sda3 swap (the installer might complain about not being able to install grub). The installation won't be able to boot as the prep partition is not formatted as HFS and won't be seen by OpenFirmware on bootup
3) Reboot using a liveCD e.g. Adelie Linux, type c to access the grub command line
4) Type the following:
(adjust ultra0 and sda to which hard disk, 0/a is top, 1/b is bottom on the G5; also adjust sda2/gpt2 to your root partition)Code:root=(ieee1275/ultra0,gpt2) linux /boot/vmlinuz root=/dev/sda2 initrd /boot/initrd boot
5) This should boot you into opensuse
6) You might need to adjust the grub command line to suit your hardware, to do so go to Yast/boot loader and edit the default append. I have edited mine to work with a Radeon HD 5770:
Code:video=offb:off video=nouveaufb:off video=radeonfb:off radeon.modeset=1 radeon.dpm=1 radeon.agpmode=-1 pci=realloc nouveau.modeset=0 quiet acpi=force loglevel=0 splash
7) If /boot/grub2/grub.cfg is already present, you can skip this step. If not, then go to Yast/Boot Loader and save the configuration. If /boot/grub2/grub.cfg is still not there, then you need to fully install grub, not just the yast bootloader frontend. In terminal type:
Code:sudo zypper install grub2 sudo grub2-install sudo grub2-mkconfig -o /boot/grub2/grub.cfg
8) You will need to create a CHRP file called ofboot.b. This file will be allow your boot partition to be selectable in the startup menu (holding down Option). The file also contains a badge icon. A template can be downloaded here:
(look for ofboot.b)GRUB on Open Firmware (PowerPC) - Gentoo wiki
Type:
(paste the file contents)Code:nano ~/ofboot.b
Edit the openfirmware boot line
to suit your needs, e.g:Code:boot hd:3,\grub\grub.img
Code:boot ultra0:1,grub
save (Ctrl-O)
9) You now need to make your prep partition bootable to openfirmware. You need to adjust /dev/sda1 if this is not your PreP partition.
Code:sudo zypper install hfsutils #(be sure that this is your PreP partition, adjust otherwisde) sudo hformat /dev/sda1 sudo hmount /dev/sda1 sudo hcopy /boot/grub2/grub :grub sudo hcopy /boot/grub2/grub.cfg :grub.cfg sudo hcopy ~/ofboot.b :ofboot.b sudo hattrib -t tbxi :ofboot.b sudo hattrib -b : sudo humount
You should have openSuse up and running and selectable in the boot menu.
If you want to set it as the default boot device, you will need to run
Code:nvram --update-config boot-device='first-boot/@0:1,\\:tbxi'
(adjust 0:1 to your drive : PreP-partition)
OpenSuse is pretty snappy on the PM G5 quad and, frankly, visually quite impressive. OpenGL and OpenCL work fine, there is out-of-the-box support for Radeon HD cards AND unlike under Ubuntu and Debian, Gnome/Wayland is fully supported on the GF7800 GTX (only flashback works with the latter under those). If you do end up using the GF7800 GTX change your grub append to:
Code:video=offb:off video=nouveaufb:off video=radeonfb:off nouveau.modeset=1 nouveau.config=NvMSI=0 radeon.modeset=0 quiet acpi=force loglevel=0 splash
EDIT: for now don't update to kernel 5.15.8, acpi doesn't seem to work all the time anymore, but you can stick to 5.12.X
Cheers,
And thanks to @LightBulbFun, @mansley12 and @LuigiBurdo whose posts got me to get this to work
Cheers,
It also would apply to final-run PowerBook G4s with the redesigned logic boards (i.e., the A1138 and A1139 from late 2005), as these are known to boot successfully from a GPT-formatted volume.
I should remember to try this. Most of my drives are formatted with Apple Partition (I only need PPC machines to be bootable from external drive), but I got a couple of spare ones. USB however (one got FW400 in it too, but I can’t make it recognized over FW for w/e reason).
Wasn't the last iBook also in that list? Not sure about the silently upgraded Mac Mini G4.
It works on the Late 2005 iBook's too( R9550 gfx ), I've tested it. It does not work on the R9200 GFX iBook G4's.
I feel like I’ve booted GPT on my Mini. I can’t remember though. I’ll give it a shot this week and let you guys know.
Hi Alice,
So I can confirm that the Mini G4 (silent upgrade version) does indeed boot from GUID, at least from FireWire, from target mode from a Quad, and to be sure that the Quad wasn't providing GUID to the mini via some OpenFirmware commands I booted SL from a GUID-formatted USB external hard drive via
Code:
boot ud:2;\\:tbxiSo yes we can add the mini G4 (silent upgrade) to the list of ppc macs that can boot from GUID, along with the G5 Quad, G5 DC, iMac G5 iSight. I would also try on the PB G4 DSLD.
We would need to try it on the regular mini G4 to be sure it's not a silent upgrade -specific feature.
Btw since the iMac G5 iSight and Quad (the latter via manual insertion of RAM sizes in OF) supports 4Gb RAM sticks and booting from GUID, could it be that the mini G4 (silent upgrade) supports 2Gb PC-3200 sticks? It would have to be out-of-the box support though like for the iMac G5 iSight, since without a stick directly recognised by OF (and there's only one DIMM slot) it won't even make it to OF to manually insert the bank-sizes into.
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I can also confirm that the G5 DP does not boot from GUID, but I think this was known and is a showstopper for the current version of OpenSUSE Tumbleweed. The one way I can think of, apart from cloning a working partition from a GUID disk onto an Apple one, would be to install an old version of Tumbleweed (the 2015 version doesn't require GUID, it sees the Apple partitions and would have let me install it if I hadn't messed up the PReP partition; the current version absolutely requires GUID and won't even see the disk during install if it's Apple-partitioned) and update from there on...
I would also give it a try on the regular iMac G5, since it's AGP and also has PC-3200 like the mini G4, I'll let you know after the DSLD which sounds promising (it does have DDR2 like the iMac G5 iSight and G5 Quad/DC so more modern architecture even than the mini G4)