Re: [SeaBIOS] [PATCH v3 0/3] usb: add xhci support

[Gerd Hoffmann]

On Mo, 2013-11-04 at 14:06 +0200, Michael S. Tsirkin wrote:
> On Mon, Nov 04, 2013 at 09:52:42AM +0100, Gerd Hoffmann wrote:
> > > Looks like this breaks isapc support in qemu.
> > > To test: check out qemu 1.6 (latest version has other bugs)
> >
> > Any chance this is just the size of the bios, i.e. isapc not being able
> > to deal with a 256k bios?
> >
> > cheers,
> >   Gerd
>
> Possibly. But what exactly is the issue?

Given that the top 128k of the bios are mapped below 1M there is a high
chance that jumping from 128k to 256k causes issues, especially as
adding the xhci driver doesn't touch any code path which would actually
be executed on a isapc machine ...

Didn't investigate in detail.  Maybe isapc memory init is different.

cheers,
  Gerd