version of the system for 68030 cards

[forsyth@plan9.cs.york.ac.uk forsyth@plan9.cs.york.ac.uk]

a student here, Dave Stringer-Calvert, attempted to port the system to a Sun-3/80.
he got most of the way through, but foundered on a lack of information from Sun
about the way the Lance and DVMA interacted.
i've now revised and completed the work to make a port of the Plan 9 cpu/terminal kernel
to a 68030 VME system, the Eltec Eurocom 6.  we inherited
quite a few of those cards, and we've now got some student projects using them under Plan 9.

if anyone else has some Eltec 6 cards and is interested, let me know.
the only bit still causing trouble is the wd33c93a scsi interface,
where there seems to be some Eltec-specific subtlety. sometimes
it works, but often it doesn't.  (i currently think they botched
the interaction between DBA and single-byte mode.)  the system runs
happily over the net from our file server, using the local bus Lance card.
i have a replacement boot PROM for the card that will boot a kernel using
BOOTP and TFTP.  i've also got reasonable drivers for the 8536 CIO that controls the parallel ports,
and for a VIP-1024 VME frame grabber, which were needed for a project.
the frame grabber provides both a file interface in '#v' and a segattach interface
(doing the latter was fiddly, but i don't think it's my fault -- the mapping
interface looks incomplete).

i haven't done a 68k Alef port yet, but i'm thinking about it, because
i'm fed up with not having it!

i intend to port any new release of Plan 9 to the Eltec environment.