Re: [PATCH v2 0/8] target/ppc: powerpc_excp improvements [74xx] (5/n)

[BALATON Zoltan]

On Thu, 27 Jan 2022, Mark Cave-Ayland wrote:
> On 27/01/2022 20:11, Fabiano Rosas wrote:
>
> > Changes from v1:
> >
> > - Restored the 'sc 1' support to avoid breaking the pegasos2 machine.
> >
> > I tested this version in the G4 with the following OSes:
> >
> > - Linux 5.15 (5.16 seems to be broken, even with master)
> > - FreeBSD 13
> > - Mac OS 9.2
> > - Mac OS Darwin 6.0
> > - Mac OS X 10.4
> > - MorphOS 3.15 (-M pegasos2 and -M mac99,via=pmu)
> >
> > Based on legoater/ppc-7.0
> >
> > v1:
> > 20220126164200.1048677-1-farosas@linux.ibm.com">https://lore.kernel.org/r/20220126164200.1048677-1-farosas@linux.ibm.com
> >
> > Fabiano Rosas (8):
> >    target/ppc: Introduce powerpc_excp_74xx
> >    target/ppc: Simplify powerpc_excp_74xx
> >    target/ppc: 74xx: Machine Check exception cleanup
> >    target/ppc: 74xx: External interrupt cleanup
> >    target/ppc: 74xx: Program exception cleanup
> >    target/ppc: 74xx: System Call exception cleanup
> >    target/ppc: 74xx: System Reset interrupt cleanup
> >    target/ppc: 74xx: Set SRRs directly in exception code
> >
> >   target/ppc/excp_helper.c | 197 +++++++++++++++++++++++++++++++++++++++
> >   1 file changed, 197 insertions(+)
>
> That certainly covers a good range MacOS images so I'm happy to give:
>
> Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
>
> Just out of curiosity have you tried booting MacOS 9.2 under KVM-PR? Last 
> time I tried on my G4 Mac Mini here, OS X worked fine but 9.2 failed early 
> after jumping into the 68k emulator. Unfortunately due to the split real mode 
> (see 
> https://github.com/torvalds/linux/commit/c01e3f66cd5cdc1f727f4c7b0c10b3e3bdb91ba7 
> where MSR_IR != MSR_DR) I can't step through with QEMU's gdbstub to see what 
> is going wrong...

Can't comment on that as I don't have PPC hardware but in case you don't 
know it yet, check out this blog entry (and its part 2):

https://www.talospace.com/2018/08/making-your-talos-ii-into-power-mac.html

which talks about running KVM-PR on POWER9 and why MacOS may not work at 
least with newer POWER CPUs. But if you run G4 code on G4 it may be a 
different problem but still an interesting article and may give you some 
ideas.

Regards,
BALATON Zoltan