[OpenBIOS] [Qemu-ppc] [PATCH] ppc: Add MacOS VGA driver ROM

[Benjamin Herrenschmidt]

On Tue, 2016-08-02 at 09:33 +0100, Mark Cave-Ayland wrote:
> >> Perhaps a bit misleading, but I meant the installation DVD boots to
> >> the installer without the driver. It takes a long time before the
> >> installer shows.
> >> Picture is here: http://www.open.ou.nl/hsp/images/qemu/qemu_leopard.j
> >> pg
> >> I already have no keyboard at the OpenBIOS prompt when using
> >> -usbdevice keyboard, so perhaps someone else has better luck.
> > 
> > One thing I noticed too is that the first boot after a 10.4 install
> > takes a very very long time on the gray apple before making progress.
> > 
> > I'm not 100% certain at this stage but I *suspect* the kext cache
> > isn't created, causing BootX to read all of their plists, which means
> > doing a *lot* of file IOs via OpenBIOS, and I have the nagging feeling
> > that it's a pretty slow path ;-)
> 
> Hmmm yes. That's a single sector read interface wrapped by deblocker so
> it's not going to be amazingly fast. For comparison the posted virtio
> driver puts the start sector, target address and length directly into
> the descriptor so large reads there are reasonably efficient.

Looking at a verbose boot, I'd say the long delays are more caused by the
lack of a PMU or SMU, so OS X times out in multiple places waiting for a
real time clock. I'll cook something up.

Cheers,
Ben.