Re: [Qemu-devel] [PATCH 11/25] q35: Introduce q35 pc based chipset emulator

[Michael S. Tsirkin]

On Sun, Sep 16, 2012 at 09:48:25AM -0500, Anthony Liguori wrote:
> > I wonder if it's possible for q35 to have no devices
> > at all in the default machine and have it
> > fully qualified by -device switches?
> >
> > I envision -M qemu-1.3 switch that does exactly that,
> > so that machine type only handles things like
> > cross version compatibility.
> 
> It's more than just "no devices".  It's a matter of proper modeling of
> the chipset, the super I/O chip, and peripherals.

OK I guess the answer us no then.

However, if you look at hw/pc_piix.c you see a bunch of version
compatiblity code. Other systems do not have this I guess
mostly because they worry less about compatibility ATM.

Looks like if we start bothering about compatibility
for both q35 and piix we'll have a lot of
code duplication between the two.

This problem is not limited to pc though,
I expect it with time we'll have it for power and arm.

I wonder what the solution is. Move compat
code out of pc_piix, making it non pc specific?

-- 
MST