svn commit: r203053 - head/share/man/man4

[Xin LI]

Author: delphij
Date: Wed Jan 27 00:34:52 2010
New Revision: 203053
URL: http://svn.freebsd.org/changeset/base/203053

Log:
  Add a manual page for nvram(4).
  
  MFC after:	2 weeks

Added:
  head/share/man/man4/nvram.4   (contents, props changed)
Modified:
  head/share/man/man4/Makefile

Modified: head/share/man/man4/Makefile
==============================================================================
--- head/share/man/man4/Makefile	Wed Jan 27 00:30:07 2010	(r203052)
+++ head/share/man/man4/Makefile	Wed Jan 27 00:34:52 2010	(r203053)
@@ -293,6 +293,7 @@ MAN=	aac.4 \
 	nsp.4 \
 	null.4 \
 	${_nve.4} \
+	${_nvram.4} \
 	${_nxge.4} \
 	ohci.4 \
 	orm.4 \
@@ -645,6 +646,7 @@ _ndis.4=	ndis.4
 _nfe.4=		nfe.4
 _nfsmb.4=	nfsmb.4
 _nve.4=		nve.4
+_nvram.4=	nvram.4
 _nxge.4=	nxge.4
 _rr232x.4=	rr232x.4
 _speaker.4=	speaker.4

Added: head/share/man/man4/nvram.4
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ head/share/man/man4/nvram.4	Wed Jan 27 00:34:52 2010	(r203053)
@@ -0,0 +1,93 @@
+.\"
+.\"Copyright (c) 2010 iXsystems, Inc.
+.\"All rights reserved.
+.\" written by: Xin LI <delphij at FreeBSD.org>
+.\"
+.\"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 AUTHOR 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 AUTHOR 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.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd January 27, 2010
+.Dt NVRAM 4 i386
+.Os
+.Sh NAME
+.Nm nvram
+.Nd "non-volatile RAM"
+.Sh SYNOPSIS
+To compile this driver into the kernel,
+place the following line in your
+kernel configuration file:
+.Bd -ragged -offset indent
+.Cd "device nvram"
+.Ed
+.Pp
+Alternatively, to load the driver as a
+module at boot time, place the following line in
+.Xr loader.conf 5 :
+.Bd -literal -offset indent
+nvram_load="YES"
+.Ed
+.Sh DESCRIPTION
+The
+.Nm
+driver provides access to BIOS configuration NVRAM on i386 and amd64
+systems.
+.Pp
+PC motherboard uses a small non-volatile memory to store BIOS settings
+which is usually part of its clock chip and sometimes referred as
+.Dq CMOS SRAM .
+This driver exposes bytes 14 through 128 of the NVRAM, or a total of
+114 bytes, at offset zero of the device file
+.Pa /dev/nvram .
+.Pp
+This driver is useful for cloning machines that shares the same hardware
+configuration and need same BIOS setting tweaks.
+.Sh IMPLEMENTATION NOTES
+The BIOS NVRAM's bytes 16 through 31 are checksummed at byte 32.
+This driver
+.Em does not
+take care for these checksums.
+.Sh EXAMPLES
+Backup existing BIOS NVRAM to
+.Pa nvram.bin :
+.Pp
+.Dl dd if=/dev/nvram of=nvram.bin
+.Pp
+Restore BIOS NVRAM from
+.Pa nvram.bin :
+.Pp
+.Dl dd if=nvram.bin of=/dev/nvram
+.Sh SEE ALSO
+.Xr dd 1
+.Sh HISTORY
+The
+.Nm
+device driver first appeared in
+.Fx 6.4 .
+.Sh AUTHORS
+.An -nosplit
+The
+.Nm
+device driver was written by
+.An Peter Wemm .
+This manual page was written by
+.An Xin LI .