Re: [Qemu-devel] [PULL for-1.3 0/3] seabios: q35 update

[Jason Baron]

On Tue, Dec 04, 2012 at 08:40:27AM +0100, Gerd Hoffmann wrote:
>   Hi,
> 
> > 1) legacy ide mode
> > 
> > I can currently create a ide controller on the command-line using
> > '-device'. However, on the real h/w there is an IDE compatibility mode
> > which essentially advertises an ide controller at the same location that
> > the ahci lives at. In fact, it changes the PCI device id. To deal with
> > the fact that AHCI has 6 ports and thus 6 possible devices, it then adds
> > a second controller for the remaining 2 disks. This shouldn't be too
> > hard to emulate. But I'm wondering what we want the qemu interface
> > to look like? A -machine options such as:
> > '-machine q35,diskmode=ahci,ide,raid'? 
> 
> I'm wondering whenever we want to deal with that at all?
> 
> "If your guest is too old to handle ahci natively, just stick to piix."
> is a sensible policy IMHO.
> 

There was some discussion of trying to make q35 the default for 1.4, in
which case it may be important to support older OS's such as WinXP.

Anthony, do you have any opinion on this?


> > 2) HPET ACPI error
> > 
> > This line: 'IRQNoFlags () {2, 8}' in the HPET acpi table is causing the
> > folloing ACPI message (removing it makes it go away):
> 
> Hmm.  That was added to make macos x happy and is also present on real
> hardware, so I'm wondering what is going on here.
> 

I also noticed that on Windows 7, the 'IRQNoFlags' line above makes the RTC
clock complain that it does not have resources available. While removing the
above line, removes that error.

thanks,

-Jason