commands: loady: fix bug with netconsole ...

Netconsole doesn't have a baudrate. Loady supposes a console has one,
and tries to compute the console's baudrate variable value, regardless
of its existence.

This triggers a NULL pointer dereference on netconsole. If attempting
loady on a netconsole is a bit useless, barebox should not panic. Fix
this by checking the variable exists before reading its value.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Do not use macros in command help ...

The help texts are parsed by sphinx which cannot handle macros, so
replace them with their values.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

commands: harmonize in-barebox documentation ...

This patch does probably too much, but it's hard (and very
cumbersome/time consuming) to break it out. What is does is this:

* each command has one short description, e.g. "list MUX configuration"
* made sure the short descriptions start lowercase
* each command has one usage. That string contains just the
  options, e.g. "[-npn]". It's not part of the long help text.
* that is, it doesn't say "[OPTIONS]" anymore, every usable option
  is listed by character in this (short) option string (the long
  description is in the long help text, as before)
* help texts have been reworked, to make them
  - sometimes smaller
  - sometimes describe the options better
  - more often present themselves in a nicer format
* all long help texts are now created with BUSYBOX_CMD_HELP_
  macros, no more 'static const __maybe_unused char cmd_foobar_help[]'
* made sure the long help texts starts uppercase
* because cmdtp->name and cmdtp->opts together provide the new usage,
  all "Usage: foobar" texts have been removed from the long help texts
* BUSYBOX_CMD_HELP_TEXT() provides the trailing newline by itself, this
  is nicer in the source code
* BUSYBOX_CMD_HELP_OPT() provides the trailing newline by itself
* made sure no line gets longer than 77 characters
* delibertely renamed cmdtp->usage, so that we can get compile-time
  errors (e.g. in out-of-tree modules that use register_command()
* the 'help' command can now always emit the usage, even without
  compiled long help texts
* 'help -v' gives a list of commands with their short description, this
  is similar like the old "help" command before my patchset
* 'help -a' gives out help of all commands

Signed-off-by: Holger Schurig <holgerschurig@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

commands: group 'help' output ...

The old output of "help" was just producing a long list, that usually
scrolled of the screen (even on a X11 terminal). This list is more
compact, and also sorted by groups.

The old output format (plus grouping) is now available with 'help -v'.

Example:

   Information commands:
     ?, devinfo, help, iomem, meminfo, version
   Boot commands:
     boot, bootm, go, loadb, loads, loadx, loady, saves, uimage
   ...

Signed-off-by: Holger Schurig <holgerschurig@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Fix the options and protocols used by the loadx command. ...

From 3cd9702 Mon Sep 17 00:00:00 2001
From: Owen Kirby <osk@exegin.com>
Date: Thu, 8 May 2014 13:27:11 -0700
Subject: [PATCH] Fix the options and protocols used by the loadx command.

It seems like the loadx command was improperly copy/pasted from the loady
implementation, and was trying to load files using the ymodem protocol. This
patch should fix the command so that it uses xmodem, implements the -t option
and outputs the correct baudrate being used.

Signed-off-by: Owen Kirby <osk@exegin.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

commands: loady: fix Y-Modem/G option name in help message ...

Actually loady command uses '-g' option for Y-Modem/G mode
selection; see loady() function:

    while ((opt = getopt(argc, argv, "b:t:g")) > 0) {
        switch (opt) {
    ...
        case 'g':
            is_ymodemg = 1;
            break;

By mistake help message show '-y' option for Y-Modem/G mode
selection.

This patch fixes the problem.

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

console: factorise function to get the first enabled console ...

rename it to console_get_first_active

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

commands: remove old Y-Modem implementation ...

As a new implementation of Y-Modem protocol is available,
switch from old implementation to the new one :
 - remove old xyzModem* files
 - remove old command loady2
 - rename command loady2 to loady

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Tested-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

commands: change Y-Modem implementation ...

The current Y-Modem implementation has some limitations:
 - Y-Modem/G protocol is not supported
 - Multiple files (aka. batch) transfers are not supported
 - Transfer speed over fast lines (USB console) is slow
 - Code is not trivial to maintain (personnal opinion)

This implementation tries to address all these points by
introducing loady2 command.

The effects are :
 - transfer speed for Y-Modem over USB jumps from 2kBytes/s
   to 180kBytes/s
 - transfer speed for Y-Modem/G jumps to 200kBytes/s
 - multiple file transfers are possible

This command was tested on a USB console and UART 9600bps
serial line :
 - NAKs (and retransmissions) were tested for faulty
   serial lines
 - multiple file transfers were tested
 - Y-Modem, Y-Modem/G and X-Modem transfers were tested

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Tested-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>