Re: [Qemu-devel] PPC emulation on Qemu

[J. Mayer]

On Mon, 2004-02-16 at 08:09, Benjamin Herrenschmidt wrote:
> > > What is OpenPPC standard ? So far, the most "standard" PPCs are
> > > PowerMacs ;) 
> > 
> > Well, G4 Macs are close to OpenPPC standard, which is an open platform
> > which has been described by IBM. I like it has a reference because it's
> > nearly Macs and because AIX, MacOS (X I suppose) and Linux should be
> > able to run on it.
> 
> You mean CHRP ? Hrm... AIX ? hehe, I wouldn't bet on that :) OS X
> neither. But at least for OS X, you can write your own drivers,
> like MOL does.
> 

No, I meant OpenPPC, but it seems that IBM doesn't promote it anymore:
the pages disapeared from their site.... So maybe it's now another
virtual standard platform :-(

> > Yes I know it can run Linux, but what I wanted to point is that (if I'm
> > not wrong) it's not able to run any OS (ie AIX or pegasos or, why not
> > (?), BeOS or AmigaOS) like a real machine would.
> 
> It could. All depends on which HW you emulate.

Yes, I'd like qemu to be able to emulate the largest combination of
hw... I don't really know if I will ever try to emulate Amiga, but as
the main use of PPC is embedded hardwares, it sounds good to have an
easily "hw" tunable emulator...

> > I agree that MOL exactly intend to do this, and does it well, but I
> > think qemu should really emulate the whole execution environment...
> > 
> > Does the OSI calls mechanism needs patched OS and/or firmware ?
> 
> It's an addition. MOL can run without it, it's just an optimisation
> so you can load special drivers into the host OS to makes things
> much faster / more useable.

All right, it seems to me that you can not always patch the emulated
system for different reasons...

> On MacOS, it makes a lot of sense since the drivers can be provided
> by the bootloader at boot or even in the ROM of some PCI cards, so
> MOL can transparently get those loaded into the host operating
> system when it's MacOS 9 or X.

OK, seems a good way for proceeding.

> Also, for OS X, MOL actually loads a special kext that patches the
> kernel to remove it's use of MMU split mode, which isn't necessary
> under emulation and actually very slow to emulate.

This, I'd like to avoid, as I'd like to keep the system in the state it
is... But I may change my mind.

I just rsync'ed the latest mol, and it appears to me that openbios isn't
inside. It seems that it's only available through proprietary bk
software...
Is there a way to get it using a standard open mechanism (ie rsync or
CVS ?). It would be glad, as I cannot and never want to use any
proprietary software on my linux boxes...

-- 
J. Mayer <address@hidden>
Never organized