68030 kernel port of Plan 9

Existing 68020 and 68040 ports formed the basis for a port to the 68030-based Eltec Eurocom-6 in a VME crate. This port was used for student project work at the University of York: developing neural network software to control a robot. The robot's camera was attached to a VME frame grabber card in the Eltec crate; connections from a parallel port controlled the robot's motors; input from a joystick allowed manual control. The devices could be controlled by programs running in the crate (as a CPU server), or imported by another machine running Plan 9 (a Sun-3) for transparent remote control.

Some of the work might be useful to people considering a port to other 68030 platforms, such as the Amiga or the older 68030-based NeXt cube not supported by the Plan 9 distribution. In particular:

• Modifications are needed to the Plan 9 distribution's 680x0 compiler suite to support the 68030 MMU instructions. These are available now, as separate boddle files:
  • updates to the assembler, /sys/src/cmd/2a
  • updates to the loader, /sys/src/cmd/2l
  • updates to the machine definition 2.out.h in /sys/src/cmd/2c
• The 68040 MMU code for the NeXt needs significant changes to support the 68030's related but different MMU.

The Plan 9 kernel for the Eltec, including MMU support and drivers, is also available, as a boddle against /sys/src/9/next:

• Fetch the boddle, and create /sys/src/9/eltec by doing the following:
  
  1. cd /sys/src/9
     
  2. rc 9eltec.rc -X /n/cd/sys/src/9/next
     
  3. mv 889686630 eltec
     
  (where the last argument to the rc command refers to your CDROM source for the NeXt kernel).
• Several drivers included in that boddle are available separately if you haven't got Plan 9 source code: Zilog 8536 CIO and VIP-1024 VME frame grabber drivers.
• I am happy to make the source code of the replacement Eltec boot ROM available to anyone with a Plan 9 licence who needs it. (It uses stripped-down versions of some Plan 9 drivers.) See my mail address below.