[SeaBIOS] [PATCH 2/2] accept MADT over fw_cfg

[Michael S. Tsirkin]

On Thu, Mar 21, 2013 at 01:14:38PM +0000, David Woodhouse wrote:
> On Thu, 2013-03-21 at 15:12 +0200, Michael S. Tsirkin wrote:
> > On Thu, Mar 21, 2013 at 01:04:35PM +0000, David Woodhouse wrote:
> > > On Thu, 2013-03-21 at 13:56 +0100, Laszlo Ersek wrote:
> > > > - for an earlier qemu, the option must be set,
> > > > - for a later qemu the option must be clear &&
> > > >   (no -acpitable switch must be specified on the qemu cmldine ||
> > > >    one -acpitable switch must load a MADT)
> > > 
> > > Hm, that sounds like it won't be possible to build one version of
> > > SeaBIOS that works for *both* old and new qemu. That doesn't seem like a
> > > great idea. I'd prefer something like:
> > > 
> > > - If Qemu provides the 'core' ACPI tables (i.e. not just SSDT) then 
> > >   SeaBIOS uses them.
> > > - Otherwise, it makes its own.
> > > 
> > > 
> > > -- 
> > > dwmw2
> > 
> > It might simplify life for someone bisecting qemu
> > as you don't need to rebuild seabios after each
> > bisect but is this really a common workflow?
> 
> Not bisection, but perhaps switching between an old and a new version of
> qemu.
> 
> > Anyway, I am not against such runtime flags.
> > 
> > If we add to this an option to build a minimal BIOS
> > that only works with the new QEMU, do we have a deal?
> 
> Yeah, definitely. The code for SeaBIOS to build its own should certainly
> be optional. It should be possible to build a minimal SeaBIOS which
> *can't*.

Okay that's exactly what me and Laszlo are working on.
We want to add a special way to build qemu and seabios
such that they work with tables in qemu, then add
runtime detection on top.

The advantage is that we can make progress
without keeping lots of patches out of tree.
Unless of course Kevin nacks this all ...

> -- 
> dwmw2