mac68k

OpenBSD/mac68k used to run on many of the Motorola 680x0-based Apple Macintosh computers. It used to require a Motorola 68020 or better processor, with an external Motorola 68851 PMMU in case of a 68020. The OpenBSD/mac68k port was discontinued after the 5.1 release.

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History:

The mac68k port of OpenBSD was derived from NetBSD/mac68k, and it used to support most of the same hardware as NetBSD.

Active building and testing of OpenBSD/mac68k was discontinued after OpenBSD 4.6 due to lack of interest with developers and builder.

Eventually the lack of a proper firmware interface, requiring the use of a MacOS application as the bootloader, with little or no possibility of updating this application to match progress in OpenBSD (let alone rebuild it with a free software toolchain) convinced the developers to give up supporting this port, and remove the code from the tree.

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Supported hardware:

Supported models

OpenBSD/mac68k used to run on a large part of the 680x0-based Macintosh computers. The kernel itself had support for the following processor combinations:

• 68020 with 68851 PMMU and 68881 FPU
• 68030 with 68882 FPU
• 68040 (not including the 68LC040)

The following Macintosh models used to be supported and tested. This means that at least the SCSI controller, serial console and on-board ethernet would function on these models. On some of these machines, a full 68040 CPU was required to replace the default 68LC040 CPU.

• Classic family: SE30
• LC family: LC, LC II, LC III, LC III+, LC475, Performa 400-430, Performa 450, Performa 460, Performa 475, Performa 476
• Centris family: 610, 650
• Quadra family: 605, 610, 630, 650, 660AV, 700, 800, 840AV, 900, 950

Supported devices

• Internal SCSI controllers and peripherals:
  • Quadra/Centris series' onboard NCR 53c96 SCSI controller (esp).
  • Macintosh II-series', Performa, and LC-series' onboard NCR 5380 SCSI controller (ncrscsi, sbc).
  • SCSI disk drives (sd).
  • SCSI cdrom drives (cd).
  • Autochangers (ch).
  • Tape drives (st).
• Internal sound (asc).
• NuBus internal expansion bus (nubus).
• Internal video and most NuBus video cards (macfb).
• Both internal serial ports (zsc).
• ADB keyboards and mice (adb) (except on the IIfx, Quadra 900 and 950).
• Ethernet cards based on the Natl. Semiconductor 8390 (Asante, Apple, and a few others) (ae).
• Quadra/Centris AV series' onboard MACE ethernet (mc).
• Some ethernet cards based on the SONIC chip including internal Ethernet on many of Apple's non-AV Quadras/Centrises (sn).

Untested systems

The following Macintosh models used to be untested, and/or lacked support for major subsystems.

• Classic family: Color Classic, Classic II
• Macintosh II family: Mac II, IIx, IIcx, IIci, IIsi, IIfx, IIvi, IIvx, Performa 600
• 500 family: 520, 550, 575, 580, Mac TV

Unsupported systems

• PowerPC-based Macs. Some of these are supported in the OpenBSD/macppc port.
• Powerbook family. Hardware capabilities limit the usability of these systems.
• Machines based on the 68LC040 processor. Unfortunately, the chip itself contains a major bug for which there is no software workaround available in OpenBSD.

Unsupported devices

• Apple Communication Slot (CS) ethernet cards.
• Any other NuBus card not listed above.
• Floppy drive.
• IOP ADB subsystem on the IIfx, Quadra 900 and 950.
• IDE drives.

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Getting and installing OpenBSD/mac68k:

The last supported OpenBSD/mac68k release was OpenBSD 5.1.