All rights reserved.
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: releng/10.2/share/man/man4/nvram2env.4 233648 2012-03-29 05:02:12Z eadler $
.Dd April 3, 2011 .Dt NVRAM2ENV 4 .Os .Sh NAME .Nm nvram2env .Nd "copy nvram-like data into kernel environment" .Sh SYNOPSIS .Cd "device nvram2env" .Sh DESCRIPTION .Nm implements a simple method of reading the NVRAM-like data and information stored in flash and storing it in the kernel environment. It can then be used by various device drivers at boot-time.
p The NVRAM-like data is an array of zero terminated strings. Each string contains the string name, "=" delimiter and the string value.
p .Nm copies the environment values into kernel environment using the kernel setenv call.
p Configuration of .Nm is done in .Xr device.hints 5 defining the NVRAM base address, fallback base address, maxsize and flags.
p .Nm is currently MIPS-specific. .Ss base base - physical address where data block is stored. .Ss fallbackbase fallbackbase - physical address where data block is stored, but only if not found at base. .Ss maxsize maxsize - maximum size of data block. .Ss flags flags - control flags, used to select nvram type and enable/disable CRC check. l -tag -width indent t Fa 0x0001 Avoid CRC checking. Currently CRC checking is not implemented, so to be future compatible, please set it to "1". t Fa 0x0002 Use format "Generic", skip uint32_t field, then zero terminating array of strings. t Fa 0x0004 Use Broadcom CFE format. uint32_t signature "FLSH", uint32_t size, three unused fields uint32_t, then data. t Fa 0x0008 Use U-Boot format, uint32_t crc, then zero terminating array of strings. .El .Sh EXAMPLES Usage in U-Boot case: d -literal -offset indent hint.nvram.0.base=0x1f030000 hint.nvram.0.maxsize=0x2000 hint.nvram.0.flags=3 # 1 = No check, 2 = Format Generic hint.nvram.1.base=0x1f032000 hint.nvram.1.maxsize=0x4000 hint.nvram.1.flags=3 # 1 = No check, 2 = Format Generic .Ed
p CFE nvram with fallback: d -literal -offset indent hint.nvram.0.base=0x1fff8000 hint.nvram.0.fallbackbase=0x1fc00400 hint.nvram.0.flags=4 # 4 = Format Broadcom .Ed
p but seems for CFE nvram preferred to read both blocks:
p NVRAM partition: Static, CFE internal d -literal -offset indent hint.nvram.0.flags=0x05 # Broadcom + nocheck hint.nvram.0.base=0x1fc00400 .Ed
p Dynamic, editable form CFE, override values from first d -literal -offset indent hint.nvram.1.flags=0x05 # Broadcom + nocheck hint.nvram.1.base=0x1cff8000 .Ed .Sh SEE ALSO .Xr kenv 1 , .Xr kenv 2 . .Sh HISTORY .Nm first appeared in .Fx 9.0 . .Sh AUTHORS .An -nosplit .Nm .An Aleksandr Rybalko Aq ray@ddteam.net .