Re: [Qemu-devel] [ADD] PPC processor emulation

[Chad Page]

On 18 Nov 2003, Jocelyn Mayer wrote:

> Well, you're right, in some way:
> there is no syscall emulation to do for vl. But you have to emulate
> a machine that looks like a real one. I think most of the softmmu code
> for ix86 could be re-used for PPC and that peripheral emulation could be
> separated into hardware emulation, independant from the target, and 
> bus-glue, which defines how the device will be accessed for a given
> target. I think that trying to have some code to emulate a CHRP or a
> PREP machine would be a good start, but we _need_ PCI for those targets.
> But, if we get one of those hardware emulated, with improvements for
> the CPU emulation to handle supervisor instructions and exceptions,
> we would be able to try to boot AIX, Linux, maybe AUX & old MacOSes.
> 
> It would be great to do this !

        AUX was 68K only IIRC.  But on the MacOS front if we can glom code
from MacOnLinux - or beef up user space mode and emulate the MOL kernel
module - then we could get everything from 8.6 to 10.3 working.  The older
MacOS's are actually tougher because you have to have a Mac ROM.

        MOL can't run a "stock" Linux kernel, yet... the problem with
LinuxPPC is there *is* no such thing as a stock kernel, unless you
actually emulate Mac HW.

> In my opinion, the hardest points are: PPC emulation improvement,
> cleaning the current vl code to separate x86 dedicated parts from
> generic ones and PCI. But I don't think we have to worry about PCI: x86
> emulation will need it too :=)

        Yup... it's kind of surreal to play with Linux under qemu - "ppro"
cpu, but with 486-era peripherals... and more importantly using bus
mastered IO will be much more efficient.  I wonder if the bochs code could
be used as a reference for at least some of it, although I think they
mostly emulate ISA stuff too (and yet need the speed boost much more ;) )

        - Chad
 
> Regards.
> -- 
> Jocelyn Mayer <address@hidden>
> Never organized
> 
> 
> 
> _______________________________________________
> Qemu-devel mailing list
> address@hidden
> http://mail.nongnu.org/mailman/listinfo/qemu-devel
>