> A lot of information, like the memory mapping and configuration, video
> mode(s) and frame buffer addreses, etc.  Stuff that we can't really get
> any other (reasonable) way given the dearth of documentation that Apple
> makes available.

I don't think any of the information we get from MacOS anymore is really
critical. We scan the memory mapping left by "MacOS" but by the time
MacOS is loaded the ROMs have already set up the "MacOS" memory map.

The code in INTVIDTEST2 should eliminate the need to wory about stuff like
checking video modes and frame buffer addresses. 

Video device initialization is done *extremely* late in the game under
NetBSD, which is bad. However, if memory serves, the ROMs know what screen
is the console (and it's base address) which they store in a low-mem global
that MacOS reads. We could do the same and use that as a place to do printfs
until video is properly initialized. I suppose that's no worse than what
the Linux-pmac folks do with the Open Firmware console.