xref: /openbsd/distrib/notes/macppc/prep (revision d485f761)
1To be able to boot the OpenBSD/MACHINE installation program, you will
2need to acquire some limited knowledge of OpenFirmware, the low-level
3process that controls the microprocessor after hardware initialization
4and diagnostics are performed but before control is handed to the
5operating system.
6
7To access Open Firmware you should simultaneously hold down the
8Command, Option, O and F keys immediately upon booting.  You will
9be presented with information and a ">" prompt that will look something
10like this (example taken from a Power Macintosh G4):
11
12Apple PowerMac3,1 2.4f1 BootROM built on 02/18/00 at 09:44:35
13Copyright 1994-2000 Apple Computer, Inc.
14All Rights Reserved
15
16Welcome to Open Firmware
17To continue booting, type "mac-boot" and press return
18To shut down, type "shut-down" and press return
19
20 ok
210 >
22
23
24Important Open Firmware command examples:
25
26boot cd:,ofwboot /OSREV/MACHINE/bsd.rd
27		(boot from an appropriately prepared
28		OpenBSD CD in the CD/DVD drive)
29
30boot enet:,ofwboot /bsd.rd
31		(netboot from a pre-configured bootp/tftp/nfs
32		server containing the "ofwboot" and "bsd.rd"
33		files at the root directory of the tftp server)
34
35boot ide1:,ofwboot /bsd
36		(After installation, boot /bsd from the slave
37		 device on the second ATA bus)
38
39mac-boot	(boot into MacOS)
40reset-all	(reboot the machine)
41shut-down	(halt the machine; shutdown)
42printenv	(print current machine variables)
43setenv		(set a machine variable)
44devalias	(list device aliases; useful for locating other
45		devices in the machine such as hard drives etc)
46
47As seen above, device aliases typically take the form of "ide", "cd"
48etc.  To boot to an alternative device you may substitute them
49with entries from this list (example devices taken from a Power
50Macintosh G4):
51
52ultra0 = hd = master device, primary ATA bus (factory-installed drive)
53ultra1 =      slave device, primary ATA bus
54ide0   = cd = master device, secondary ATA bus (CD/DVD drive)
55ide1   =      slave device, secondary ATA bus (Zip drive, if installed)
56enet   =      motherboard ethernet device
57
58
59Other Open Firmware command examples:
60
61setenv auto-boot? false
62		(force the machine to wait at Open Firmware
63		for user input at next reboot; options are true/false)
64
65setenv boot-device ide:,ofwboot
66		(force the machine to boot into OpenBSD
67		automatically at next reboot)
68
69dev /		(change to root level of the device tree)
70pwd		(show current location in the device tree)
71ls		(show items at current location in the device tree)
72words		(show methods of items at current location in the device tree)
73.properties	(show properties of items at current location in the device tree)
74
75
76To reset a Power Macintosh to the factory-configure Open Firmware settings,
77simultaneously hold down the Command, Option, P, R keys immediately upon
78booting.  Typically the machine will then attempt to load Mac OS, if
79available.
80
81
82Sharing a disk with MacOS:
83
84OpenBSD/MACHINE is capable of booting either from a dedicated disk using
85a MBR partitioned disk or sharing a disk with MacOS.
86
87If the disk is to be shared between MacOS and OpenBSD, it is necessary
88to reformat and install the MacOS partitions first, using "Drive Setup",
89leaving space on the disk as an "Unused" partition.
90If the disk was previously partitioned, it is possible to reuse a Partition
91for OpenBSD, as long as it is not the first Partition on the disk.
92The bootloader is expected to be found in that first (HFS) Partition.
93
94For dedicated disks, MACHINE port boots off a boot program in
95an MSDOS filesystem. This is set up by the install program
96and no special setup is required.
97