OFWBOOT(8) | System Manager's Manual (macppc) | OFWBOOT(8) |
ofwboot
,
ofwboot.elf
, ofwboot.xcf
— Open Firmware boot command
ofwboot |
Open Firmware is a FORTH-like command interpreter started by the
BootROM after the power-on self test (POST). This command interpreter allows
the user flexibility in choosing how their machine boots an operating
system. NetBSD uses Open Firmware to initialize many
of the devices in a system and uses it to load the primary bootloader,
ofwboot
.
The information in this man page should only serve as a guideline for users. Apple has made many revisions to Open Firmware, and the earlier versions had many problems and inconsistencies. You may find that a boot command that works on one model will not work on another.
In this man page, only one Open Firmware command will be
described, boot
, because it is used to pass
arguments to ofwboot
. The Open Firmware
boot
command takes up to three arguments:
boot
[boot-device [boot-file]] [options]
where
The first argument, boot-device, actually designates the primary bootloader location and its name in the form:
device:
[partition-num][,\bootloader-filename]
A typical example, from a PowerBook (FireWire), is
/pci@f2000000/mac-io@17/ata-4@1f000/@0:9,\ofwboot.xcf
Note that colon (‘:
’)
delimits the device to the left, and comma
(‘,
’) separates the bootloader
filename from the first part. For Open Firmware versions before 3, the
primary bootloader is installed in partition “zero”, and it is
not necessary to specify the bootloader-filename. For
Open Firmware version 3, you must specify the bootloader filename.
Open Firmware stores aliases to common devices in NVRAM. In the
example the above,
/pci@f2000000/mac-io@17/ata-4@1f000/@0 is the path
on a PowerBook (FireWire) to the built-in ATA/100 hard drive. Use the
devalias
command in Open Firmware to print out a
list of common device names on a particular model. The
boot-device above could then be simplified to:
hd:9,\ofwboot.xcf
bootloader-filename is usually
ofwboot.xcf
. See also the
FILES section for further discussion.
If boot-device is omitted from the
boot
command, the Open Firmware variable
boot-device
is used.
It may be necessary to specify the boot-file if Open Firmware does not know where to find the kernel. The default is to load the file named netbsd on partition “a” from the device used to load the primary bootloader.
For systems with Open Firmware versions less than 3 which are set
up using sysinst
, the
boot-file argument is not necessary. Systems with Open
Firmware version 3 may need to specify the
boot-file.
The syntax is similar to the boot-device argument:
[boot-file-device:
partition-num/
][kernel-name]
This is a little different, since a kernel-name may be specified without listing a boot-file-device and partition-num. Additionally, a boot-file-device and partition-num may need to be specified, while using the default kernel-name.
If no kernel-name is specified, the primary bootloader will try to find kernels named either netbsd or netbsd.gz on the boot-device or (if specified) boot-file-device.
Possible options are:
If set, the following Open Firmware variables will be used to determine which boot-device and boot-file Open Firmware should use when booting a system. If the user specifies arguments on the command line, these values are overridden.
boot-device
boot-file
auto-boot?
false
will present the
user with an Open Firmware command prompt after power-on reset. A value of
true
will automatically boot the system using the
variables boot-device
and
boot-file
. (This is not really related to the boot
command, but is included for completeness.)To restore these variables to their default values, use the
set-default
Open Firmware command:
set-default boot-device
The three files ofwboot
,
ofwboot.elf
, and ofwboot.xcf
are the same program, in different executable formats.
ofwboot
is installed via
installboot(8) on
systems with Open Firmware versions less than 3. It is not necessary to
specify this file name on the Open Firmware boot
command, as it is stored in a special location in the
NetBSD partition that is marked
“bootable” in the Apple partition map entry. The bootable
partition can be specified as partition “zero”. For example,
the following command might be used to boot from a SCSI device with ID 2:
0 >boot scsi-int/sd@2:0
.ofwboot.xcf
is in XCOFF format. This file is used
on all Open Firmware 3 systems, and on Open Firmware systems prior to 3
when the bootloader is not installed in partition “zero”,
such as from an ISO-9660 format CD-ROM.ofwboot.elf
is in
elf(5) format and only
functions on systems with Open Firmware version 3. To avoid confusion, all
users should be using ofwboot.xcf
, as
ofwboot.elf
offers no additional functionality. It
is only included for historical reasons.ofwboot
), an
INSTALL kernel (with limited device drivers), and the
sysinst
utility in a RAM disk. Since Open Firmware
does not care what media files are loaded from, only whether they are
supported and in the correct format, this disk image may be placed on
media other than floppy disks, such as hard drives or Zip disks. Use
dd(1) on Unix, or
DiskCopy
on MacOS 9.1 or later, or
suntar
on any MacOS version to copy this image
onto the media.sysinst
included.In the following examples
‘0 >
’ is the Open
Firmware prompt.
0 > boot -s
0 > boot
hd:,\ofwboot.xcf
ofwboot
from the USB flash drive:
0 > boot
usb0/disk:,\ofwboot.elf hd/netbsd.new -d
0 > boot
usb1/disk:,\ofwboot.elf hd/netbsd.new -d
devalias
” and
“dev usb0 ls
” commands etc.0 > boot
cd:,\ofwboot.xcf
0 > boot
scsi/sd@3:0
0 > boot
usb0/disk@1:3,\ofwboot.xcf
0 > boot
usb1/disk@1:3,\ofwboot.xcf
0 > boot fd:0
0 > boot enet:0
0 > boot enet:0
ultra1:0
0 > boot
hd:,\\:tbxi
0 > boot
hd:10,\\:tbxi
DEFAULT CATCH!, code=FF00300 at %SRR0: FF80AD38 %SRR1: 00001070
Could be “device not found” or I/O errors on the
device. The numbers are just for example. If the error is caused by I/O
errors (especially on CD boot), retrying the same command after restarting
Open Firmware by reset-all
command might help.
CLAIM failed
real-base
variable settings.
Can't LOAD from this device
load
.
0 > boot yy:0/netbsd RESETing to change Configuration!
0 > boot ata/ata-disk@0:9 specified partition is not bootable ok
0 > boot ata/ata-disk@0:0 >> NetBSD/macppc OpenFirmware Boot, Revision 1.3 >> (root@nazuha, Fri Jun 8 22:21:55 JST 2001) no active package3337696/
Note: It is recommended to restart Open Firmware by
reset-all
command if you get these Open Firmware
errors, to avoid further unexpected random errors.
INSTALL.html
NetBSD/macppc Frequently Asked Questions
IEEE Std 1275-1994 (“Open Firmware”)
ofwboot
can only boot from devices
recognized by Open Firmware.
Early PowerMacintosh systems (particularly the 7500) seem to have problems with netbooting. Adding an arp entry at the tftp server with
arp -s booting-host-name
its-ethernet-address
may resolve this problem (see arp(8)).
Once boot failed,
0 > boot CLAIM failed ok
successive boots may not be possible. You need to type
reset-all
or power-cycle to re-initialize Open
Firmware.
June 9, 2024 | NetBSD 10.99 |