At present these values are open-coded in a few places. Add constants so
the meaning is clear.
Also add a comment to cmd_get_data_size()
Signed-off-by: Simon Glass <sjg@chromium.org>
This is defined only when __lp64__ is defined. That means that ulong is
64 bits long. Therefore we don't need to use a separate u64 type on those
architectures.
Fix up the code to take advantage of that, removing the preprocessor
conditions.
Also include the header file that defines MEM_SUPPORT_64BIT_DATA. It is
included by env.h in this file, but that might not last forever.
Signed-off-by: Simon Glass <sjg@chromium.org>
Define this macro always so we don't need the preprocessor to check it.
Convert the users to #if instead of #ifdef.
Note that '#if MEM_SUPPORT_64BIT_DATA' does not give an error if the
macro is not define. It just assumes zero.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stefan Roese <sr@denx.de>
We should not use typedefs in U-Boot. They cannot be used as forward
declarations which means that header files must include the full header to
access them.
Drop the typedef and rename the struct to remove the _s suffix which is
now not useful.
This requires quite a few header-file additions.
Signed-off-by: Simon Glass <sjg@chromium.org>
This is not really a CONFIG since it is not intended to be set by boards.
Move it into the compiler header with other similar defines, and rename
it.
Signed-off-by: Simon Glass <sjg@chromium.org>
All platforms which are using MANUAL_RELOC are jumping back to origin
location when repeatable command is called. The reason is that cmd_rep link
is not updated properly. Issue can be reproduced by rewriting origin
U-Boot location through (for example) file download by tftp command.
Fixes: 80a48dd47e ("common: command: Rework the 'cmd is repeatable' logic")
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
At present we have environment.h but this file includes all the
environment-related header files as well as internals such as
default_environment.
It seems desirable to have a new header to hold the commonly used
environment functions, so that most files can avoid including all of this
unnecessary stuff.
Create a new env.h header and move one function over to it.
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Reviewed-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
The autocompletion did not work if CONFIG_CMDLINE_PS_SUPPORT was enabled
because U-Boot was comparing the prompt string with CONFIG_SYS_PROMPT .
While this works if CONFIG_CMDLINE_PS_SUPPORT is disabled, this no longer
works if it's enabled because user can override the PS1 . Fix this by
checking prompt string against the current PS1 value.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Tom Rini <trini@konsulko.com>
When using boot scripts it can become quite hard to understand
which commands are actually executed during bootup (e.g. where
is a kernel image loaded from or which DTB is in use).
Shell scripts suffer from a similar problem and many shells address
this problem with a command execution tracer (e.g. BASH has xtrace,
which can be enabled by "set -x").
This patch introduces a command tracer for U-Boot, which prints
every command with its arguments before it is executed.
Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
Reviewed-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Add the dollar_complete() function to auto-complete arguments starting
with a '$' and use it in the cmd_auto_complete() path such that all
args starting with a $ can be auto-completed based on the available env
vars.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
[trini: Fix some linking problems]
Signed-off-by: Tom Rini <trini@konsulko.com>
The repeatable property is currently attached to the main command and
sub-commands have no way to change the repeatable value (the
->repeatable field in sub-command entries is ignored).
Replace the ->repeatable field by an extended ->cmd() hook (called
->cmd_rep()) which takes a new int pointer to store the repeatable cap
of the command being executed.
With this trick, we can let sub-commands decide whether they are
repeatable or not.
We also patch mmc and dtimg who are testing the ->repeatable field
directly (they now use cmd_is_repeatable() instead), and fix the help
entry manually since it doesn't use the U_BOOT_CMD() macro.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Some commands have a table of sub-commands. With minor adjustments,
complete_cmdv() is able to provide auto-completion for sub-commands
(it's just about passing the table of commands instead of taking the
global one).
We rename this function into complete_subcmd() and implement
complete_cmdv() as a wrapper around complete_subcmdv().
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
When auto-completing command arguments, the last argument is not
necessarily the one we need to auto-complete. When the last character is
a space, a tab or '\0' what we want instead is list all possible values,
or if there's only one possible value, place this value on the command
line instead of trying to suffix the last valid argument with missing
chars.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
command_ret_t enum contains 3 return values but only two are handled
now. Extend cmd_process_error() and handle CMD_RET_USAGE separately.
These commands are affected by this change.
cmd/demo.c
cmd/efi.c
cmd/gpio.c
cmd/qfw.c
cmd/x86/fsp.c
test/dm/cmd_dm.c
And scripts shouldn't be affected because return value is not 0. But
every command implementation can choose what it is correct to pass.
I would expect that RET_USAGE is called when parameters are not
correctly passed (have incorrect value, missing parameters)
and RET_FAILURE when correct parameters are passed but command fails.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Simon Glass <sjg@chromum.org>
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from. So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry. Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.
In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.
This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents. There's also a few places where I found we did not have a tag
and have introduced one.
Signed-off-by: Tom Rini <trini@konsulko.com>
When copying the command line buffer the target array should
at least have the same size.
Cf. definition of console_buffer in common/cli_readline.c.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Command parsing and processing code is not needed when the command line is
disabled. Remove this code in that case.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
The console includes a global variable and several functions that are only
used by a small subset of U-Boot files. Before adding more functions, move
the definitions into their own header file.
Signed-off-by: Simon Glass <sjg@chromium.org>
Add '\n' for debug msg.
Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
Cc: Tom Rini <trini@konsulko.com>
Cc: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
- Do not insert a whitespace between a function name and
an open paranthesis
- Fix comment style
- Do not split an error message into multiple lines
even if it exceeds 80 columns
- Do not split "for" statement where it fits in 80 columns
- Do not use assignment in if condition
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Simon Glass <sjg@chromium.org>
Add 64-bit data for memory commands, such as md, mw, mm, cmp. The new
size ".q " is introduced.
For 64-bit architecture, 64-bit data is enabled by default, by detecting
compiler __LP64__. It is optional for other architectures.
Signed-off-by: York Sun <yorksun@freescale.com>
U-Boot now uses errors defined in include/errno.h which are negative
integers. Commands which fail need to report the error and return 1
to indicate failure. Add this functionality in cmd_process_error().
For now this merely reports the error number. It would be possible
also to produce a helpful error message by storing the error strings
in U-Boot.
Signed-off-by: Simon Glass <sjg@chromium.org>
Compiling of full list of commands does not advance the counter,
so it always results in an empty list.
This seems to be (inadvertently?) introduced by commit
6c7c946cad.
Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>
As far as every arch has a get_timer function,
run_command_and_time_it code can now disappear.
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Acked-By: Che-Liang Chiou <clchiou@chromium.org>
[trini: s/ulong/unsigned long/ in command.h portion]
Signed-off-by: Tom Rini <trini@ti.com>
commit 199adb601f "common/misc: sparse
fixes" broke the help command trying to fix the sparse error
"command.c:44:38: error: bad constant expression".
As Henrik points out, the fix was bad because the commit used
CONFIG_SYS_MAXARGS whereas the code intended to use the maximum
number of commands (not arguments to a command).
Revert command.c changes to the original code as asked by Wolfgang.
Reported-by: Henrik Nordström <henrik@henriknordstrom.net>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
command.c:44:38: error: bad constant expression
dlmalloc.c:1468:2: warning: Using plain integer as NULL pointer
dlmalloc.c:1468:5: warning: Using plain integer as NULL pointer
dlmalloc.c:2176:12: warning: Using plain integer as NULL pointer
dlmalloc.c:2179:31: warning: Using plain integer as NULL pointer
dlmalloc.c:2382:14: warning: Using plain integer as NULL pointer
dlmalloc.c:2436:14: warning: Using plain integer as NULL pointer
dlmalloc.c:2582:31: warning: Using plain integer as NULL pointer
dlmalloc.c:2585:17: warning: Using plain integer as NULL pointer
dlmalloc.c:2646:14: warning: Using plain integer as NULL pointer
dlmalloc.c:2659:19: warning: Using plain integer as NULL pointer
dlmalloc.c:2692:19: warning: Using plain integer as NULL pointer
dlmalloc.c:2707:19: warning: Using plain integer as NULL pointer
dlmalloc.c:2708:14: warning: Using plain integer as NULL pointer
dlmalloc.c:2786:31: warning: Using plain integer as NULL pointer
dlmalloc.c:2801:12: warning: Using plain integer as NULL pointer
dlmalloc.c:2801:22: warning: Using plain integer as NULL pointer
dlmalloc.c:2926:27: warning: Using plain integer as NULL pointer
dlmalloc.c:2928:14: warning: Using plain integer as NULL pointer
dlmalloc.c:2929:12: warning: Using plain integer as NULL pointer
dlmalloc.c:3075:14: warning: Using plain integer as NULL pointer
hush.c:292:14: warning: symbol 'last_return_code' was not declared. Should it be static?
hush.c:293:5: warning: symbol 'nesting_level' was not declared. Should it be static?
hush.c:2175:20: warning: Using plain integer as NULL pointer
hush.c:2175:34: warning: Using plain integer as NULL pointer
hush.c:2210:41: warning: Using plain integer as NULL pointer
hush.c:2216:45: warning: Using plain integer as NULL pointer
hush.c:2249:25: warning: Using plain integer as NULL pointer
hush.c:2332:13: warning: symbol 'new_pipe' was not declared. Should it be static?
hush.c:2390:5: warning: symbol 'reserved_word' was not declared. Should it be static?
hush.c:2927:5: warning: symbol 'parse_stream' was not declared. Should it be static?
hush.c:3127:6: warning: symbol 'mapset' was not declared. Should it be static?
hush.c:3133:6: warning: symbol 'update_ifs_map' was not declared. Should it be static?
hush.c:3161:5: warning: symbol 'parse_stream_outer' was not declared. Should it be static?
hush.c:3295:34: warning: Using plain integer as NULL pointer
hush.c:3631:5: warning: symbol 'do_showvar' was not declared. Should it be static
image.c:1282:29: warning: Using plain integer as NULL pointer
image.c:1315:41: warning: Using plain integer as NULL pointer
image.c:1330:25: warning: Using plain integer as NULL pointer
image.c:1706:25: warning: Using plain integer as NULL pointer
main.c:510:10: warning: symbol 'hist_num' was not declared. Should it be static?
main.c:512:5: warning: symbol 'hist_list' was not declared. Should it be static?
main.c:513:6: warning: symbol 'hist_lines' was not declared. Should it be static?
usb_storage.c:195:6: warning: symbol 'usb_show_progress' was not declared. Should it be static?
usb_storage.c:440:48: warning: Using plain integer as NULL pointer
usb_storage.c:503:5: warning: symbol 'usb_stor_BBB_comdat' was not declared. Should it be static?
usb_storage.c:551:5: warning: symbol 'usb_stor_CB_comdat' was not declared. Should it be static?
usb_storage.c:629:55: warning: Using plain integer as NULL pointer
usb_storage.c:620:5: warning: symbol 'usb_stor_CBI_get_status' was not declared. Should it be static?
usb_storage.c:675:43: warning: Using plain integer as NULL pointer
usb_storage.c:668:5: warning: symbol 'usb_stor_BBB_clear_endpt_stall' was not declared. Should it be static?
usb_storage.c:679:5: warning: symbol 'usb_stor_BBB_transport' was not declared. Should it be static?
usb_storage.c:801:5: warning: symbol 'usb_stor_CB_transport' was not declared. Sh
xyzModem.c:104:1: warning: symbol 'CYGACC_COMM_IF_GETC_TIMEOUT' was not declared. Should it be static?
xyzModem.c:122:1: warning: symbol 'CYGACC_COMM_IF_PUTC' was not declared. Should it be static?
xyzModem.c:169:1: warning: symbol 'parse_num' was not declared. Should it be stat
note: hush.c's nesting_level deleted because not used.
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
This patch converts the old method of creating a list of command
onto the new LG-arrays code. The old u_boot_cmd section is converted
to new u_boot_list_cmd subsection and LG-array macros used as needed.
Minor adjustments had to be made to the common code to work with the
LG-array macros, mostly the fixup_cmdtable() calls are now passed the
ll_entry_start and ll_entry_count instead of linker-generated symbols.
The command.c had to be adjusted as well so it would use the newly
introduced LG-array API instead of directly using linker-generated
symbols.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Joe Hershberger <joe.hershberger@gmail.com>
Cc: Mike Frysinger <vapier@gentoo.org>
We currently have the same code in hush.c and main.c. This brings the
code into one place.
As an added feature, if the command function returns CMD_RET_USAGE then
cmd_process() will print a usage message for the command before
returning the standard failure code of 1.
ARM code size increases about 32 bytes with this clean-up.
Signed-off-by: Simon Glass <sjg@chromium.org>
In commit fa28bd2eef patch v1 was applied
instead of v2. This is an incremental patch to update that commit
to version 2.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
The command auto-completion does not work on architectures relying
on CONFIG_NEEDS_MANUAL_RELOC like MIPS. Cause is the missing function
pointer fixup for cmd_tbl_t::complete function in fixup_cmdtable().
This patch adds the missing pointer fixup in case of CONFIG_AUTO_COMPLETE
is defined.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
Rather than add runtime overhead of installing completion handlers, do it
statically at build time. This requires a new build time helper macro to
declare a command and the completion handler at the same time. Then we
convert the env related funcs over to this.
This gives an opportunity to also unify the U_BOOT_CMD macros.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Guard strchr/strlen from being called with NULL pointer.
This line is crashing when command "env" is called without subcommand.
The cmd is NULL in this case because the calling function "do_env"
decremented the argc without checking if there are still arguments available.
Signed-off-by: Thomas Weber <weber@corscience.de>
By now, the majority of architectures have working relocation
support, so the few remaining architectures have become exceptions.
To make this more obvious, we make working relocation now the default
case, and flag the remaining cases with CONFIG_NEEDS_MANUAL_RELOC.
Signed-off-by: Wolfgang Denk <wd@denx.de>
Tested-by: Heiko Schocher <hs@denx.de>
Tested-by: Reinhard Meyer <u-boot@emk-elektronik.de>
fixup_cmdtable() did all work for fixing up the cmdtable,
if CONFIG_RELOC_FIXUP_WORKS is not defined.
CONFIG_RELOC_FIXUP_WORKS is missing for i386! I talked
with Graeme Russ, and he will fix this soon.
Portions of this work were supported by funding from
the CE Linux Forum.
Signed-off-by: Heiko Schocher <hs@denx.de>
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>
Lots of code use this construct:
cmd_usage(cmdtp);
return 1;
Change cmd_usage() let it return 1 - then we can replace all these
ocurrances by
return cmd_usage(cmdtp);
This fixes a few places with incorrect return code handling, too.
Signed-off-by: Wolfgang Denk <wd@denx.de>
The hush shell dynamically allocates (and re-allocates) memory for the
argument strings in the "char *argv[]" argument vector passed to
commands. Any code that modifies these pointers will cause serious
corruption of the malloc data structures and crash U-Boot, so make
sure the compiler can check that no such modifications are being done
by changing the code into "char * const argv[]".
This modification is the result of debugging a strange crash caused
after adding a new command, which used the following argument
processing code which has been working perfectly fine in all Unix
systems since version 6 - but not so in U-Boot:
int main (int argc, char **argv)
{
while (--argc > 0 && **++argv == '-') {
/* ====> */ while (*++*argv) {
switch (**argv) {
case 'd':
debug++;
break;
...
default:
usage ();
}
}
}
...
}
The line marked "====>" will corrupt the malloc data structures and
usually cause U-Boot to crash when the next command gets executed by
the shell. With the modification, the compiler will prevent this with
an
error: increment of read-only location '*argv'
N.B.: The code above can be trivially rewritten like this:
while (--argc > 0 && **++argv == '-') {
char *arg = *argv;
while (*++arg) {
switch (*arg) {
...
Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Enable the auto completion (with TAB) of the environment variable name
after the editenv command.
Signed-off-by: Ralf Trbenbach <ralf.truebenbach@men.de>
Many of the help messages were not really helpful; for example, many
commands that take no arguments would not print a correct synopsis
line, but "No additional help available." which is not exactly wrong,
but not helpful either.
Commit ``Make "usage" messages more helpful.'' changed this
partially. But it also became clear that lots of "Usage" and "Help"
messages (fields "usage" and "help" in struct cmd_tbl_s respective)
were actually redundant.
This patch cleans this up - for example:
Before:
=> help dtt
dtt - Digital Thermometer and Thermostat
Usage:
dtt - Read temperature from digital thermometer and thermostat.
After:
=> help dtt
dtt - Read temperature from Digital Thermometer and Thermostat
Usage:
dtt
Signed-off-by: Wolfgang Denk <wd@denx.de>
In case of incorrect command invocations U-Boot used to print pretty
useless "usage" messages, for example:
=> nand markbad
Usage:
nand - NAND sub-system
In the result, the user would have to run the "help" command to get
the (available) information about correct command usage. Change this,
so that this information gets always printed.
Note that this changes the user interface of all commands, but
hopefully to the better.
Signed-off-by: Wolfgang Denk <wd@denx.de>
Other commands implementing subcommands can reuse this code nicely.
Signed-off-by: Detlev Zundel <dzu@denx.de>
Signed-off-by: Andreas Pfefferle <ap@denx.de>
