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.\" $NetBSD: boot.8,v 1.8 2017/07/03 21:31:00 wiz Exp $
.\"
.\" Copyright (c) 2003 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Michael Wolfson and Erik E. Fair.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.Dd February 17, 2017
.Dt BOOT 8 macppc
.Os
.Sh NAME
.Nm boot
.Nd Macppc system bootstrapping procedures
.Sh DESCRIPTION
.Ss Power fail and crash recovery
Normally, the system will reboot itself at power-up or after crashes.
An automatic consistency check of the file systems will be performed
as described in
.Xr fsck 8 ,
and unless this fails, the system will resume multi-user operations.
.Ss Cold starts
The boot ROM performs a Power On Self Test (POST) then loads Open
Firmware.
Depending on the Open Firmware variable
.Sq Ev auto-boot?
it will either stop at the Open Firmware
prompt or attempt to boot an operating system.
Depending on the contents
of the
.Sq Ev use-nvramrc? ,
.Sq Ev boot-command ,
.Sq Ev boot-device ,
and
.Sq Ev boot-file
Open Firmware variables, it will attempt to boot
.Tn MacOS ,
.Tn "MacOS X" ,
or
.Nx .
.Pp
To boot
.Nx ,
Open Firmware loads the bootloader
.Xr macppc/ofwboot 8
from the specified
.Sq Ev boot-device .
The bootloader then loads the kernel from the
.Sq Ev boot-file ,
.Pq if it exists .
Otherwise, it tries to load (in the following order):
.Pa netbsd , netbsd.gz ,
or
.Pa netbsd.macppc
on the
.Dq a
partition of the same device that had the bootloader.
.Ss "Open Firmware Commands"
An essential but incomplete list of Open Firmware commands follows.
A more thorough list is contained in the FAQ.
.Lk http://www.NetBSD.org/ports/macppc/faq.html#ofw-use
.Pp
.Ic boot
.Op Ar boot-device Op Ar boot-file
.Op Ar options
.Pp
Boot an operating system.
The default arguments for this command are taken from the Open Firmware
environment variables:
.Bl -tag -width boot-device -compact
.It Ar boot-device
primary bootloader location
.It Ar boot-file
kernel location
.It Ar options
flags passed to the kernel
.El
.Pp
.Ic reset-all
.Pp
Reset the system, and proceed as specified by the
.Sq Ev use-nvramrc?
and
.Sq Ev auto-boot?
variables.
If
.Sq Ev use-nvramrc?
is set to
.Sq Ev true ,
then the system will attempt to execute the commands stored in the
.Sq Ev nvramrc
variable.
If
.Sq Ev auto-boot?
is set to
.Sq Ev true ,
the system will attempt to use the values stored in
.Sq Ev boot-command ,
.Sq Ev boot-device ,
and
.Sq Ev boot-file
to boot the system.
If
.Sq Ev auto-boot?
is set to
.Sq Ev false ,
the system will halt at the Open Firmware prompt.
.Pp
.Ic shut-down
.Pp
Power off the system.
.Pp
.Ic setenv Ar variable Ar value
.Pp
Set an Open Firmware variable, e.g.,
.Bd -literal -offset indent
setenv auto-boot? false
setenv boot-device hd:,\eofwboot.xcf
setenv boot-file netbsd-GENERIC.gz
.Ed
.Pp
.Ic set-default Ar variable
.Pp
Set an Open Firmware variable to its default value.
.Pp
.Ic printenv Op Ar variable
.Pp
Show Open Firmware variables and values.
.Pp
.Ic eject fd
.Pp
Eject floppy disk on systems with on-board floppy drives.
.Pp
.Ic mac-boot
.Pp
Attempt to boot
.Tn MacOS
on an Open Firmware 3 system.
.Pp
.Ic bye
.Pp
Attempt to boot
.Tn MacOS
on an Open Firmware 1.0.5, 2.0.x, or 2.4 system.
.Ss "Open Firmware Variables"
An essential but incomplete list of Open Firmware variables follows.
A more thorough list is contained in the FAQ.
.Lk http://www.NetBSD.org/ports/macppc/faq.html#ofw-variables
.Bl -tag -width "ew*0_protocols"
.It Ev auto-boot?
What Open Firmware will do at system startup or reset:
.Bl -tag -width false
.It Ar true
automatically bootstrap an operating system using values from the
.Sq Ev boot-command ,
.Sq Ev boot-device ,
and
.Sq Ev boot-file
variables.
.It Ar false
stop at the Open Firmware prompt.
.El
.Pp
.It Ev use-nvramrc?
If
.Sq Ev true
runs commands in variable
.Sq Ev nvramrc .
.Pp
.It Ev real-base
Kernel memory location.
.Em "Do not modify this value on Open Firmware 3 systems \(em you may"
.Em "damage your computer" .
All other Open Firmware versions should use
.Li F00000 .
.Pp
.It Ev load-base
Bootloader memory location.
.Em "Do not modify this value on Open Firmware 3 systems \(em you may"
.Em "damage your computer" .
All other Open Firmware versions should use
.Li 600000 .
.Pp
.It Ev boot-command
The command to use for booting.
Typically, the default of
.Sq Ev boot
is used.
.Pp
.It Ev boot-device
Device from which to load primary bootloader.
Value depends on a variety of factors.
See
.Xr macppc/ofwboot 8 .
.It Ev boot-file
Kernel location.
Value depends on a variety of factors.
See
.Xr macppc/ofwboot 8 .
.Pp
.It Ev input-device
What type of console input device
.Po
.Tn ADB
keyboard,
.Tn USB
keyboard, or serial port
.Pc .
.Bl -tag -width ttya
.It Ar kbd
.Tn ADB
keyboard on models with
.Tn ADB ,
.Tn USB
keyboard on models with
.Tn USB ,
and built-in keyboard on laptops.
This is the default on some Open Firmware
2.0.x machines and all Open Firmware 2.4 and 3 machines.
.It Ar ttya
.Sq Modem
serial port on machines with serial ports.
Properties are 38400 bps, 8 bits, no parity, 1 stop bit, no handshaking.
This is the default on all
Open Firmware 1.0.5 systems and some Open Firmware 2.0.x systems.
.It Ar ttyb
.Sq Printer
serial port on machines with serial ports.
Properties are the same as the
.Sq Modem
port.
.It Ar scca
Serial port on Xserve models.
Properties are 57600 bps, 8 bits, no
parity, 1 stop bit, no handshaking.
.El
.Pp
.It output-device
What type of console output device (On-board video, AGP video, PCI video,
built-in LCD, or serial console).
Value depends on a variety of factors.
See
.Xr macppc/ofwboot 8
and
.Lk http://www.NetBSD.org/ports/macppc/faq.html#ofw-input-output-devices
.Pp
.It nvramrc
If
.Sq Ev use-nvramrc?
is set to true, these
.Tn FORTH
commands will be run when the computer is reset
.Pp
.El
.Ss "Normal Operation"
When Open Firmware loads the primary bootloader, it will print something
like the following:
.Bd -unfilled -offset indent
 loading XCOFF
 tsize=CC50 dsize=14AC bsize=2668 entry=640000
 SECTIONS:
 .text    00640000 00640000 0000CC50 000000E0
 .data    0064D000 0064D000 000014AC 0000CD30
 .bss     0064E4B0 0064E4B0 00002668 00000000
 loading .text, done..
 loading .data, done..
 clearing .bss, done..
.Ed
.Pp
When
.Xr macppc/ofwboot 8
is started, it prints something like the following:
.Bd -unfilled -offset indent
 >> NetBSD/macppc OpenFirmware Boot, Revision 1.7
 >> (autobuild@tgm.daemon.org, Thu Feb  6 17:50:27 UTC 2003)
.Ed
.Pp
When
.Xr macppc/ofwboot 8
is loading the kernel, it prints something like the following:
.Bd -unfilled -offset indent
 4395364+254568 [220144+193803]=0x4d477c
  start=0x100000
.Ed
.Pp
When the
.Nx
kernel has started it prints a banner similar to the following:
.Bd -literal -offset indent
 Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003
     The NetBSD Foundation, Inc.  All rights reserved.
 Copyright (c) 1982, 1986, 1989, 1991, 1993
     The Regents of the University of California.  All rights reserved.

 NetBSD 1.6ZC (GENERIC) #0: Tue Sep 30 13:09:10 UTC 2003
        autobuild@tgm.NetBSD.org:/autobuild/HEAD/macppc/OBJ/autobuild/HEAD/src/sys/arch/macppc/compile/GENERIC
.Ed
.Ss "After bootstrap"
Once the
.Nx Ns Tn /macppc
kernel is booted normally
it initializes itself and proceeds to start the system.
An automatic consistency check of the file systems takes place,
and unless this fails, the system comes up to multi-user operation.
.Pp
The proper way to shut the system down is with the
.Xr shutdown 8
command.
.Pp
If the system crashes, it will enter the kernel debugger,
.Xr ddb 4 ,
if it is configured in the kernel.
If the crash occurred during initialization and the debugger is
not present or is exited, the kernel will halt the system.
.Pp
If the crash occurred during normal operation and the debugger
is not present or is exited, the system will attempt a dump to the
configured dump device (which will be automatically recovered with
.Xr savecore 8
during the next bootstrap cycle), and after the dump is complete (successful
or not) the kernel will attempt a reboot.
.Sh FILES
.Bl -tag -width /usr/mdec/bootxx_cd9660 -compact
.It Pa /boot
.Nx
secondary bootstrap program (Open Firmware 1.x and 2.x)
.It Pa /netbsd
default
.Nx
system kernel
.It Pa /usr/mdec/bootxx
.Nx
primary bootstrap program (Open Firmware 1.x and 2.x) a.k.a.
.Dq "partition zero"
bootloader
.It Pa /usr/mdec/ofwboot
.Nx
secondary bootstrap program (Open Firmware 1.x and 2.x)
.It Pa /usr/mdec/ofwboot.xcf
primary bootstrap for netboot and
.Dq cd9660
.Pq Tn ISO 9660 ,
.Dq MS-DOS ,
.Dq HFS ,
and
.Dq HFS+
file systems.
.El
.Sh SEE ALSO
.Xr ddb 4 ,
.Xr intro 4 ,
.Xr diskless 8 ,
.Xr halt 8 ,
.Xr init 8 ,
.Xr installboot 8 ,
.Xr macppc/ofwboot 8 ,
.Xr rc 8 ,
.Xr reboot 8 ,
.Xr savecore 8 ,
.Xr shutdown 8
.Pp
.Lk http://www.NetBSD.org/ports/macppc/faq.html
.br
.Lk http://www.NetBSD.org/docs/network/netboot/
.Sh STANDARDS
.St -ieee1275-94
.Lk http://playground.sun.com/1275/home.html
.Sh BUGS
The device names used by
.Nx Ns Tn /macppc
and Open Firmware often have no relation to each other.
.Pp
Apple Computer's Open Firmware implementation is easily confused.
It is best to reboot your computer
after a failed boot attempt,
.Ic halt ,
or
.Ic "shutdown -h" .
Use the Open Firmware
.Ic reset-all
command.
.Pp
Apple Computer's Open Firmware implementation is notoriously bad.
Thorough instructions for installing and booting
.Nx
are in the install notes
.Pq Pa INSTALL.html
included with every release of
.Nx .