Re: [Qemu-devel] [RFC] qemu VGA endian swap low level drawing changes

[Gerd Hoffmann]

On Mi, 2014-06-18 at 23:03 +1000, Benjamin Herrenschmidt wrote:
> On Wed, 2014-06-18 at 13:18 +0200, Gerd Hoffmann wrote:
> > The dispi interface has a versioned id too (VBE_DISPI_IDx) which we
> > could use too.  Which makes sense IMO if we add the register to the
> > bochs dispi registers.
> > 
> > We could also place the register in pci config space, then indicate it
> > exists by either creating it a vendor pci capability or by pci
> > revision.
> 
> I'm not fan of the config space option .. I don't like vendor specific
> stuff in PCI config space. I prefer adding a DISPI VBE register since
> we never compile that out (despite the ifdef's being still around) do
> we ?

Yes, the #ifdefs are a leftover, it is always compiled in.

> I've tried to engage with the Bochs folks on their mailing list to make
> sure they agree in principle at least but have had no reply yet.

If we can get to an agreement here -- perfectly fine.

If not -- then I prefer to play save and not use a vbe register to avoid
ending up with two incompatible bochs interface revisions.  If you don't
like the pci config space option -- the mmio bar has plenty of free
space left ;)

cheers,
  Gerd