1.\" $NetBSD: boot.8,v 1.2 2013/10/05 08:20:22 skrll Exp $ 2.\" 3.\" Copyright (c) 2010 Microsoft Corp. 4.\" Copyright (c) 2010 NetBSD Foundation, Inc. 5.\" All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.Dd October 5, 2013 29.Dt BOOT 8 emips 30.Os 31.Sh NAME 32.Nm boot 33.Nd system bootstrapping procedures 34.Sh DESCRIPTION 35The 36.Nx 37kernel is started by placing it near the beginning of physical 38memory and transferring to the entry point. 39Since the system is not reenterable, 40it is necessary to read it in from disk or the network 41each time it is to be bootstrapped. 42.Ss Power fail and crash recovery 43FPGA devices lose their content upon loss of power and must be re-programmed. 44This is usually accomplished via a JTAG cable programmer, or using a FLASH device. 45Once the eMIPS processor has been programmed into the FPGA, the system will normally boot itself. 46An automatic consistency check of the file systems will be performed, 47and unless this fails, the system will resume multi-user operations. 48.Sh Xilinx XUP, ML401 and ML402 49On these systems the kernel is normally read in from disk. The path used for automatic booting is 50.Nm /netbsd , 51but it can be overridden in the optional file 52.Nm /boot.config 53stored in the root of the disk filesystem. The user can also type a different filename and a combination of boot options. 54.Sh BeSquare BEE3 55On this system there is no local disk and booting over the network is the only option. 56Network boot can also be explicitly selected by hitting 57.Nm f 58at the boot loader prompt. 59.Sh KERNEL ARGUMENTS 60At the boot loader prompt, the user may boot 61.Nx 62with a number of options that are passed to the kernel unmodified. Parsing of these options is 63defined in the file 64.Nm /sys/boot_flag.h 65Some additional flags are as follows. 66.Bl -tag -width xxx -offset indent 67.It Li e 68Empty -- this argument requests 69.Nx 70to ignore all symbolic information and empty its initial symbol table. 71.It Li n 72Name -- Prompt for the root file system device, the system crash dump 73device, and the path to 74.Xr init 8 . 75.It Li N 76NoName -- Do not prompt for the root file system device, the system crash dump 77device, and the path to 78.Xr init 8 . 79If the configured-in devices are present, use them. 80.It Li s 81Single -- Boot only to single-user mode. 82.El 83.Sh SEE ALSO 84.Xr ddb 4 , 85.Xr halt 8 , 86.Xr init 8 , 87.Xr installboot 8 , 88.Xr rc 8 , 89.Xr reboot 8 , 90.Xr savecore 8 , 91.Xr shutdown 8 92.Sh HISTORY 93The 94.Nm 95command is 96.Ud . 97