Re: Qemu / KVM On Powermac G5 MP970

[Dan Whitehouse]

Zoltan,
I have a “toy” macos9 install which works well (if extremely slowly).
I also have Debian powerpc (32-bit) installed and that works reasonably well 
but slowly too.
Finally after a lot of struggle over the weekend I have an install of Debian 
ppc64 (64-bit) which “works”.
It’s so slow it seems to always drop me to the emergency shell because of the 
filesystems timing out, but there may be a way to increase that in the kernel 
command line. It also doesn’t seem to want to shutdown or reboot properly - but 
maybe passing -M mac99,via=pdu may help that. I’m testing at the time of 
writing. So slow progress but I almost have something I can begin testing with.

Thanks,

Dan

> On 20 Jan 2023, at 23:05, BALATON Zoltan <balaton@eik.bme.hu> wrote:
> 
> Hello,
> 
> Keeping the qemi-ppc list posted in case there's anybody who could add 
> something to this or for later reference for the benefit of those trying it 
> later so they don't have to get through the same again.
> 
> On Thu, 19 Jan 2023, Dan Whitehouse wrote:
>> Thanks for your advice - attempting to install a 64-bit Debian guest was my 
>> next target, although I believe I struggled with that when I tried it before 
>> (hence the 32-bit guests!).
>> I wasn’t actually sure if KVM would work with a 32-bit guest even if I could 
>> get it working hence my question.
>> I’ll read through those links.
> 
> I came across this lengthy forum thread:
> 
> http://macos9lives.com/smforum/index.php/topic,4600.75.html
> 
> where they debugged booting MacOS9 on G5 and found the same dcbz problem the 
> other blog posts also mentioned and also rfi vs rfid which may be a problem 
> as well. It also shows how to enable debug logging in MacOS9 nanokernel with 
> the AAPL,debug property in the device tree which may be useful to know how 
> far it gets and what's happening.
> 
> After verifying KVM works with Linux guest you could go on to check if at 
> least these known instruction differences with G5 that cause problem with 
> MacOS9 are handled correctly by KVM or check you're not getting the same 
> problem. Even if these are handled there can be problem with BATs that aren't 
> there on G5 so maybe you'll need some patches to MacOS9 to boot. They used 
> QEMU with gdb to debug this but I think with TCG, don't know if the same also 
> works with KVM. This could give you some more info on where to go next or how 
> to debug this.
> 
> Regards,
> BALATON Zoltan