- add an option for the output device in the hope that this can
be made non-blocking at some stage.
- define an alias for the disk device, required by dev/ofw/ofw_disk.c
- shift iobus to 0x9000000 so as not to clash with the OpenFirmware
entry point of 0x8000400 when address decoding.
- down-tone comments about the disk dev config :-)
the MacIO chip and PSIM's IOBus. Bus-specific drivers should
use the identify method to attach themselves to nexus so
interrupt can be allocated before the h/w is probed. The
'early attach' routine in openpic is used for this stage
of boot. When h/w is probed, the openpic can be attached
properly. It will enable interrupts allocated prior to
this.
