2 .\"Copyright (c) 2010 iXsystems, Inc.
3 .\"All rights reserved.
4 .\" written by: Xin LI <delphij@FreeBSD.org>
6 .\"Redistribution and use in source and binary forms, with or without
7 .\"modification, are permitted provided that the following conditions
9 .\"1. Redistributions of source code must retain the above copyright
10 .\" notice, this list of conditions and the following disclaimer.
11 .\"2. Redistributions in binary form must reproduce the above copyright
12 .\" notice, this list of conditions and the following disclaimer in the
13 .\" documentation and/or other materials provided with the distribution.
15 .\"THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 .\"ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 .\"IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 .\"ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 .\"FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 .\"DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 .\"OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 .\"HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 .\"LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 .\"OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 .Nd "non-volatile RAM"
36 To compile this driver into the kernel,
37 place the following line in your
38 kernel configuration file:
39 .Bd -ragged -offset indent
43 Alternatively, to load the driver as a
44 module at boot time, place the following line in
46 .Bd -literal -offset indent
52 driver provides access to BIOS configuration NVRAM on i386 and amd64
55 PC motherboard uses a small non-volatile memory to store BIOS settings
56 which is usually part of its clock chip and sometimes referred as
58 This driver exposes bytes 14 through 128 of the NVRAM, or a total of
59 114 bytes, at offset zero of the device file
62 This driver is useful for cloning machines that shares the same hardware
63 configuration and need same BIOS setting tweaks.
64 .Sh IMPLEMENTATION NOTES
65 The BIOS NVRAM's bytes 16 through 31 are checksummed at byte 32.
68 take care for these checksums.
70 Backup existing BIOS NVRAM to
73 .Dl dd if=/dev/nvram of=nvram.bin
75 Restore BIOS NVRAM from
78 .Dl dd if=nvram.bin of=/dev/nvram
84 device driver first appeared in
90 device driver was written by
92 This manual page was written by