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2016-10-08spl: saveenv: adding saveenv support in SPLB, Ravi1-1/+1
By default saveenv option is not supported for SPL. This patch enable the support for save environment variable for SPL build. Enable save environment support in SPL after setenv. By default the saveenv option is not provided in SPL, but some boards need this support in 'Falcon' boot, where SPL need to boot from different images based on environment variable set by OS. For example OS may set "reboot_image" environment variable to "recovery" inorder to boot recovery image by SPL. The SPL read "reboot_image" and act accordingly and change the reboot_image to default mode using setenv and save the environemnt. Signed-off-by: Ravi Babu <ravibabu@ti.com> Reviewed-by: Simon Glass <sig@chromium.org> change in v1: - dropped SUPPORT, use CONFIG_SPL_SAVEENV - updates the comments in mmc_private.h
2016-10-06Various, accumulated typos collected from around the tree.Robert P. J. Day1-1/+1
Fix various misspellings of: * deprecated * partition * preceding,preceded * preparation * its versus it's * export * existing * scenario * redundant * remaining * value * architecture Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Reviewed-by: Jagan Teki <jteki@openedev.com> Reviewed-by: Stefan Roese <sr@denx.de>
2016-07-25hashtable: Fix compiler warning on 32-bit sandboxSimon Glass1-5/+5
This fixes a mismatch between the %zu format and the type used on sandbox. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Tom Rini <trini@konsulko.com>
2016-07-16Various, unrelated tree-wide typo fixes.Robert P. J. Day1-1/+1
Fix a number of typos, including: * "compatble" -> "compatible" * "eanbeld" -> "enabled" * "envrionment" -> "environment" * "FTD" -> "FDT" (for "flattened device tree") * "ommitted" -> "omitted" * "overriden" -> "overridden" * "partiton" -> "partition" * "propogate" -> "propagate" * "resourse" -> "resource" * "rest in piece" -> "rest in peace" * "suport" -> "support" * "varible" -> "variable" Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
2015-09-15env: import: hashtable: Free memory allocated before exiting from himport_r()Lukasz Majewski1-1/+4
ithout this patch memory is not released on early exit. Signed-off-by: Lukasz Majewski <l.majewski@majess.pl>
2015-09-15env: import: hashtable: Prevent buffer overrun when importing environment ↵Lukasz Majewski1-2/+3
from file Lets consider following scenario: - One uses echo -n "key=value" to define environment variable in a file (single variable) - The file content is "key=value" without any terminating byte (e.g. 0x0a or 0x0d). - The file is loaded to u-boot non zero'ed RAM buffer (with load command). - Then "env import -t -r $loadaddr $filesize" is executed. - Due to lack of proper termination byte we have classical example of buffer overrun. This patch prevents from this by allocating one extra byte than size and explicitly null terminate it. There should be no change for normal env import operation after applying this patch. Signed-off-by: Lukasz Majewski <l.majewski@majess.pl>
2014-07-22Add option -r to env import to allow import of text files with CRLF as line ↵Alexander Holler1-1/+16
endings When this option is enabled, CRLF is treated like LF when importing environments from text files, which means CRs ('\r') in front of LFs ('\n') are just ignored. Drawback of enabling this option is that (maybe exported) variables which have a trailing CR in their content will get imported without that CR. But this drawback is very unlikely and the big advantage of letting Windows user create a *working* uEnv.txt too is likely more welcome. Signed-off-by: Alexander Holler <holler@ahsoftware.de>
2013-11-08env: fix the env export varnamePierre Aubert1-1/+1
The env export command doesn't export the first variable of the list since commit 5a31ea04c9ee5544fbb70ad7597ea4b294840eab "env grep" - reimplement command using hexport_r() Signed-off-by: Pierre Aubert <p.aubert@staubli.com>
2013-09-20Cosmetic: Fix a number of typos, no functional changes.Robert P. J. Day1-1/+1
Fix various misspellings of things like "environment", "kernel", "default" and "volatile", and throw in a couple grammar fixes. Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
2013-07-24Add LGPL-2.1+ SPDX-License-Identifier to source filesWolfgang Denk1-14/+1
Signed-off-by: Wolfgang Denk <wd@denx.de>
2013-05-09env: throw an error when an empty key is usedLucian Cojocar1-0/+6
If the environment contains an entry like "=value" "\0" we should throw an error when parsing the environment. Otherwise, U-Boot will enter in an infinite loop. Signed-off-by: Lucian Cojocar <cojocar@gmail.com>
2013-05-01"env grep" - add support for regular expression matchesWolfgang Denk1-3/+26
When CONFIG_REGEX is enabled, the new option "-e" becomes available which causes regular expression matches to be used. This allows for example things like these: - print all MAC addresses: => env grep -e eth.*addr eth1addr=00:10:ec:80:c5:15 ethaddr=00:10:ec:00:c5:15 - print all variables that have at least 2 colons in their value: => env grep -v -e :.*: addip=setenv bootargs ${bootargs} ip=${ipaddr}:${serverip}:${gatewayip}:${netmask}:${hostname}:${netdev}:off panic=1 eth1addr=00:10:ec:80:c5:15 ethaddr=00:10:ec:00:c5:15 ver=U-Boot 2013.04-rc1-00289-g497746b-dirty (Mar 22 2013 - 12:50:25) etc. Signed-off-by: Wolfgang Denk <wd@denx.de>
2013-05-01"env grep" - reimplement command using hexport_r()Wolfgang Denk1-36/+28
Also drop hstrstr_r() which is not needed any more. The new code is way more flexible. Signed-off-by: Wolfgang Denk <wd@denx.de>
2013-05-01hashtable: preparations to use hexport_r() for "env grep"Wolfgang Denk1-8/+24
The output of "env grep" is unsorted, and printing is done by a private implementation to parse the hash table. We have all the needed code in place in hexport_r() alsready, so let's use this instead. Here we prepare the code for this, without any functional changes yet. Signed-off-by: Wolfgang Denk <wd@denx.de>
2012-12-13env: Add environment variable flagsJoe Hershberger1-0/+4
Currently just validates variable types as decimal, hexidecimal, boolean, ip address, and mac address. If the entry is not found in the env ".flags", then look in the static one. This allows the env to override the static definitions, but prevents the need to have every definition in the environment distracting you. Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
2012-12-13env: Add support for callbacks to environment varsJoe Hershberger1-4/+63
Add support for per-variable callbacks to the "hashtable" functions. Signed-off-by: Joe Hershberger <joe.hershberger@ni.com> !!!fix comment in callback
2012-12-13env: Hide '.' variables in env print by defaultJoe Hershberger1-1/+4
When printing all variables with env print, don't print variables that begin with '.'. If env print is called with a '-a' switch, then include variables that begin with '.' (just like the ls command). Variables printed explicitly will be printed even without the -a. Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
2012-12-13env: Refactor apply into change_okJoe Hershberger1-27/+43
Move the read of the old value to inside the check function. In some cases it can be avoided all together and at the least the code is only called from one place. Also name the function and the callback to more clearly describe what it does. Pass the ENTRY instead of just the name for direct access to the whole data structure. Pass an enum to the callback that specifies the operation being approved. Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
2012-12-13env: Consolidate common code in hsearch_r()Joe Hershberger1-34/+37
The same chunk of code was replicated in two places and the following changes will make that chunk grow a bit, so combine into a static func. Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
2012-12-13env: Refactor do_apply to a flagJoe Hershberger1-17/+20
Use a flag in hsearch_r for insert mode passed from import to allow the behavior be different based on use. Now that "do_check" is called for all imports, ensure console init is complete before updating the console on relocation import Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
2012-10-01OMAP: networking support for SPLIlya Yanok1-0/+2
This patch adds support for networking in SPL. Some devices are capable of loading SPL via network so it makes sense to load the main U-Boot binary via network too. This patch tries to use existing network code as much as possible. Unfortunately, it depends on environment which in turn depends on other code so SPL size is increased significantly. No effort was done to decouple network code and environment so far. Signed-off-by: Ilya Yanok <ilya.yanok@cogentembedded.com> Acked-by: Joe Hershberger <joe.hershberger@ni.com> Signed-off-by: Tom Rini <trini@ti.com>
2012-09-18env: delete selected vars not present in imported envGerlando Falauto1-8/+42
When variables explicitly specified on the command line are not present in the imported env, delete them from the running env. If the variable is also missing from the running env, issue a warning. Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com> Reviewed-by: Marek Vasut <marex@denx.de>
2012-09-18env: check and apply changes on delete/destroyGerlando Falauto1-6/+10
Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com> Reviewed-by: Marek Vasut <marex@denx.de>
2012-09-18env: add check/apply logic to himport_r()Gerlando Falauto1-1/+19
Change hashtable so that a callback function will decide whether a variable can be overwritten, and possibly apply the changes. So add a new field to struct hsearch_data: o "apply" callback function to check whether a variable can be overwritten, and possibly immediately apply the changes; when NULL, no check is performed. And a new argument to himport_r(): o "do_apply": whether to call the apply callback function NOTE: This patch does not change the current behavior. Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com> Reviewed-by: Marek Vasut <marex@denx.de>
2012-09-18env: make himport_r() selective on variablesGerlando Falauto1-1/+26
Add 2 new arguments to himport_r(): o "nvars", "vars": number and list of variables to take into account (0 means ALL) NOTE: This patch does not change the current behaviour. Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com> Reviewed-by: Marek Vasut <marex@denx.de>
2011-11-22sandbox: Fix warnings in hashtable.cSimon Glass1-5/+5
This fixes a few printf() strings for size_t which are missing the 'z' modifier. Signed-off-by: Simon Glass <sjg@chromium.org> Acked-by: Mike Frysinger <vapier@gentoo.org>
2011-11-08env: allow to export only selected variablesWolfgang Denk1-2/+13
New syntax: env export [-t | -b | -c] [-s size] addr [var ...] With this change it is possible to provide a list of variables names that shall be exported. Whenno arguments are given, the whole environment gets exported. NOTE: The new handling of the "size" argument means a change to the user API. Signed-off-by: Wolfgang Denk <wd@denx.de>
2011-10-17Replace space and tab checks with isblankJason Hobbs1-1/+3
These are various places I found that checked for conditions equivalent to isblank. Signed-off-by: Jason Hobbs <jason.hobbs@calxeda.com>
2011-07-30Constify getenv(), setenv() and hash code functionsWolfgang Denk1-3/+3
This is needed to get rid of build warnings like main.c:311: warning: passing argument 2 of 'setenv' discards qualifiers from pointer target type which result from commit 09c2e90 "unify version_string". Signed-off-by: Wolfgang Denk <wd@denx.de> Cc: Andreas Bießmann <andreas.devel@googlemail.com>
2011-04-28common: add a grepenv commandKim Phillips1-0/+23
u-boot environments, esp. when boards are shared across multiple users, can get pretty large and time consuming to visually parse. The grepenv command this patch adds can be used in lieu of printenv to facilitate searching. grepenv works like printenv but limits its output only to environment strings (variable name and value pairs) that match the user specified substring. the following examples are on a board with a 5313 byte environment that spans multiple screen pages: Example 1: summarize ethernet configuration: => grepenv eth TSEC etact=FM1@DTSEC2 eth=FM1@DTSEC4 ethact=FM1@DTSEC2 eth1addr=00:E0:0C:00:8b:01 eth2addr=00:E0:0C:00:8b:02 eth3addr=00:E0:0C:00:8b:03 eth4addr=00:E0:0C:00:8b:04 eth5addr=00:E0:0C:00:8b:05 eth6addr=00:E0:0C:00:8b:06 eth7addr=00:E0:0C:00:8b:07 eth8addr=00:E0:0C:00:8b:08 eth9addr=00:E0:0C:00:8b:09 ethaddr=00:E0:0C:00:8b:00 netdev=eth0 uprcw=setenv ethact $eth;setenv filename p4080ds/R_PPSXX_0xe/rcw_0xe_2sgmii_rev2_high.bin;setenv start 0xe8000000;protect off all;run upimage;protect on all upuboot=setenv ethact $eth;setenv filename u-boot.bin;setenv start eff80000;protect off all;run upimage;protect on all upucode=setenv ethact $eth;setenv filename fsl_fman_ucode_P4080_101_6.bin;setenv start 0xef000000;protect off all;run upimage;protect on all usdboot=setenv ethact $eth;tftp 1000000 $dir/$bootfile;tftp 2000000 $dir/initramfs.cpio.gz.uboot;tftp c00000 $dir/p4080ds-usdpaa.dtb;setenv bootargs root=/dev/ram rw console=ttyS0,115200 $othbootargs;bootm 1000000 2000000 c00000; => Example 2: detect unused env vars: => grepenv etact etact=FM1@DTSEC2 => Example 3: reveal hardcoded variables; e.g., for fdtaddr: => grepenv fdtaddr fdtaddr=c00000 nfsboot=setenv bootargs root=/dev/nfs rw nfsroot=$serverip:$rootpath ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname:$netdev:off console=$consoledev,$baudrate $othbootargs;tftp $loadaddr $bootfile;tftp $fdtaddr $fdtfile;bootm $loadaddr - $fdtaddr ramboot=setenv bootargs root=/dev/ram rw console=$consoledev,$baudrate $othbootargs;tftp $ramdiskaddr $ramdiskfile;tftp $loadaddr $bootfile;tftp $fdtaddr $fdtfile;bootm $loadaddr $ramdiskaddr $fdtaddr => grep $fdtaddr fdtaddr=c00000 my_boot=bootm 0x40000000 0x41000000 0x00c00000 my_dtb=tftp 0x00c00000 $prefix/p4080ds.dtb nohvboot=tftp 1000000 $dir/$bootfile;tftp 2000000 $dir/$ramdiskfile;tftp c00000 $dir/$fdtfile;setenv bootargs root=/dev/ram rw ramdisk_size=0x10000000 console=ttyS0,115200;bootm 1000000 2000000 c00000; => This patch also enables the grepenv command by default on corenet_ds based boards (and repositions the DHCP command entry to keep the list sorted). Signed-off-by: Kim Phillips <kim.phillips@freescale.com> Cc: Kumar Gala <kumar.gala@freescale.com> Cc: Andy Fleming <afleming@freescale.com>
2011-04-28env: fix env var autocompletionKim Phillips1-1/+1
commit 560d424b6d7cd4205b062ad95f1b104bd4f8bcc3 "env: re-add support for auto-completion" fell short of its description - the 'used' logic in hmatch_r was reversed - 'used' is 0 if the hash table entry is not used, or -1 if deleted. This patch makes hmatch_r actually match on valid ('used') entries, instead of skipping them and failing to match anything. typing 'printenv tft' and hitting 'tab' now displays valid choices for variable names. Signed-off-by: Kim Phillips <kim.phillips@freescale.com> Cc: Mike Frysinger <vapier@gentoo.org> Tested-by: Mike Frysinger <vapier@gentoo.org>
2011-03-22Fix hash table deletion to prevent lost entriesPeter Barada1-5/+13
Use negative used value to mark deleted entry. Search keeps probing past deleted entries. Adding an entry uses first deleted entry when it hits end of probe chain. Initially found that "ramdiskimage" and "preboot" collide modulus 347, causing "preboot" to be inserted at idx 190, "ramdiskimage" at idx 191. Previous to this fix when "preboot" is deleted, "ramdiskimage" is orphaned. Signed-off-by: Peter Barada <peter.barada@logicpd.com> Tested-by: Wolfgang Denk <wd@denx.de>
2011-01-09env: re-add support for auto-completionMike Frysinger1-0/+20
Currently, only basic completion is supported (no globs), but this is what we had previously. Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2010-12-17hashtable: drop all non-reentrant versionsMike Frysinger1-38/+2
The non-reentrant versions of the hashtable functions operate on a single shared hashtable. So if two different people try using these funcs for two different purposes, they'll cause problems for the other. Avoid this by converting all existing hashtable consumers over to the reentrant versions and then punting the non-reentrant ones. Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2010-10-27Coding Style cleanupWolfgang Denk1-6/+6
Signed-off-by: Wolfgang Denk <wd@denx.de>
2010-10-06lib/hashtable.c: add CONFIG_ENV_MIN_ENTRIESAndreas Bießmann1-4/+8
This patch adds a new config parameter for adjusting the calculation of hash table size when importing a buffer. When importing a extremely small buffer (e.g. the default_environment) the old calculation generated a hash table which could hold at most the buffer content but no more entires. The new calculation add a fixed number of entries to the result to fit better for small import buffers. This amount may be configured by the user in board file to adjust the behaviour. Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
2010-09-19New implementation for internal handling of environment variables.Wolfgang Denk1-9/+23
Motivation: * Old environment code used a pessimizing implementation: - variable lookup used linear search => slow - changed/added variables were added at the end, i. e. most frequently used variables had the slowest access times => slow - each setenv() would calculate the CRC32 checksum over the whole environment block => slow * "redundant" envrionment was locked down to two copies * No easy way to implement features like "reset to factory defaults", or to select one out of several pre-defined (previously saved) sets of environment settings ("profiles") * No easy way to import or export environment settings ====================================================================== API Changes: - Variable names starting with '#' are no longer allowed I didn't find any such variable names being used; it is highly recommended to follow standard conventions and start variable names with an alphanumeric character - "printenv" will now print a backslash at the end of all but the last lines of a multi-line variable value. Multi-line variables have never been formally defined, allthough there is no reason not to use them. Now we define rules how to deal with them, allowing for import and export. - Function forceenv() and the related code in saveenv() was removed. At the moment this is causing build problems for the only user of this code (schmoogie - which has no entry in MAINTAINERS); may be fixed later by implementing the "env set -f" feature. Inconsistencies: - "printenv" will '\\'-escape the '\n' in multi-line variables, while "printenv var" will not do that. ====================================================================== Advantages: - "printenv" output much better readable (sorted) - faster! - extendable (additional variable properties can be added) - new, powerful features like "factory reset" or easy switching between several different environment settings ("profiles") Disadvantages: - Image size grows by typically 5...7 KiB (might shrink a bit again on systems with redundant environment with a following patch series) ====================================================================== Implemented: - env command with subcommands: - env print [arg ...] same as "printenv": print environment - env set [-f] name [arg ...] same as "setenv": set (and delete) environment variables ["-f" - force setting even for read-only variables - not implemented yet.] - end delete [-f] name not implemented yet ["-f" - force delete even for read-only variables] - env save same as "saveenv": save environment - env export [-t | -b | -c] addr [size] export internal representation (hash table) in formats usable for persistent storage or processing: -t: export as text format; if size is given, data will be padded with '\0' bytes; if not, one terminating '\0' will be added (which is included in the "filesize" setting so you can for exmple copy this to flash and keep the termination). -b: export as binary format (name=value pairs separated by '\0', list end marked by double "\0\0") -c: export as checksum protected environment format as used for example by "saveenv" command addr: memory address where environment gets stored size: size of output buffer With "-c" and size is NOT given, then the export command will format the data as currently used for the persistent storage, i. e. it will use CONFIG_ENV_SECT_SIZE as output block size and prepend a valid CRC32 checksum and, in case of resundant environment, a "current" redundancy flag. If size is given, this value will be used instead of CONFIG_ENV_SECT_SIZE; again, CRC32 checksum and redundancy flag will be inserted. With "-b" and "-t", always only the real data (including a terminating '\0' byte) will be written; here the optional size argument will be used to make sure not to overflow the user provided buffer; the command will abort if the size is not sufficient. Any remainign space will be '\0' padded. On successful return, the variable "filesize" will be set. Note that filesize includes the trailing/terminating '\0' byte(s). Usage szenario: create a text snapshot/backup of the current settings: => env export -t 100000 => era ${backup_addr} +${filesize} => cp.b 100000 ${backup_addr} ${filesize} Re-import this snapshot, deleting all other settings: => env import -d -t ${backup_addr} - env import [-d] [-t | -b | -c] addr [size] import external format (text or binary) into hash table, optionally deleting existing values: -d: delete existing environment before importing; otherwise overwrite / append to existion definitions -t: assume text format; either "size" must be given or the text data must be '\0' terminated -b: assume binary format ('\0' separated, "\0\0" terminated) -c: assume checksum protected environment format addr: memory address to read from size: length of input data; if missing, proper '\0' termination is mandatory - env default -f reset default environment: drop all environment settings and load default environment - env ask name [message] [size] same as "askenv": ask for environment variable - env edit name same as "editenv": edit environment variable - env run same as "run": run commands in an environment variable ====================================================================== TODO: - drop default env as implemented now; provide a text file based initialization instead (eventually using several text files to incrementally build it from common blocks) and a tool to convert it into a binary blob / object file. - It would be nice if we could add wildcard support for environment variables; this is needed for variable name auto-completion, but it would also be nice to be able to say "printenv ip*" or "printenv *addr*" - Some boards don't link any more due to the grown code size: DU405, canyonlands, sequoia, socrates. => cc: Matthias Fuchs <matthias.fuchs@esd-electronics.com>, Stefan Roese <sr@denx.de>, Heiko Schocher <hs@denx.de> - Dropping forceenv() causes build problems on schmoogie => cc: Sergey Kubushyn <ksi@koi8.net> - Build tested on PPC and ARM only; runtime tested with NOR and NAND flash only => needs testing!! Signed-off-by: Wolfgang Denk <wd@denx.de> Cc: Matthias Fuchs <matthias.fuchs@esd-electronics.com>, Cc: Stefan Roese <sr@denx.de>, Cc: Heiko Schocher <hs@denx.de> Cc: Sergey Kubushyn <ksi@koi8.net>
2010-09-19Add hash table support as base for new environment codeWolfgang Denk1-0/+721
This implementation is based on code from uClibc-0.9.30.3 but was modified and extended for use within U-Boot. Major modifications and extensions: * hsearch() [modified / extended]: - While the standard version does not make any assumptions about the type of the stored data objects at all, this implementation works with NUL terminated strings only. - Instead of storing just pointers to the original objects, we create local copies so the caller does not need to care about the data any more. - The standard implementation does not provide a way to update an existing entry. This version will create a new entry or update an existing one when both "action == ENTER" and "item.data != NULL". - hsearch_r(): Instead of returning 1 on success, we return the index into the internal hash table, which is also guaranteed to be positive. This allows us direct access to the found hash table slot for example for functions like hdelete(). * hdelete() [added]: - The standard implementation of hsearch(3) does not provide any way to delete any entries from the hash table. We extend the code to do that. * hexport() [added]: - Export the data stored in the hash table in linearized form: Entries are exported as "name=value" strings, separated by an arbitrary (non-NUL, of course) separator character. This allows to use this function both when formatting the U-Boot environment for external storage (using '\0' as separator), but also when using it for the "printenv" command to print all variables, simply by using as '\n" as separator. This can also be used for new features like exporting the environment data as text file, including the option for later re-import. - The entries in the result list will be sorted by ascending key values. * himport() [added]: - Import linearized data into hash table. This is the inverse function to hexport(): it takes a linear list of "name=value" pairs and creates hash table entries from it. - Entries without "value", i. e. consisting of only "name" or "name=", will cause this entry to be deleted from the hash table. - The "flag" argument can be used to control the behaviour: when the H_NOCLEAR bit is set, then an existing hash table will kept, i. e. new data will be added to an existing hash table; otherwise, old data will be discarded and a new hash table will be created. - The separator character for the "name=value" pairs can be selected, so we both support importing from externally stored environment data (separated by NUL characters) and from plain text files (entries separated by newline characters). - To allow for nicely formatted text input, leading white space (sequences of SPACE and TAB chars) is ignored, and entries starting (after removal of any leading white space) with a '#' character are considered comments and ignored. - NOTE: this means that a variable name cannot start with a '#' character. - When using a non-NUL separator character, backslash is used as escape character in the value part, allowing for example fo multi-line values. - In theory, arbitrary separator characters can be used, but only '\0' and '\n' have really been tested. Signed-off-by: Wolfgang Denk <wd@denx.de>