Ts4300 initrd

After the board is first booted you will be at this shell:

  Finished booting in 0.514 seconds
  Type 'tshelp' for help
  [root@4300 /]# 

Note:

Your version dates may be different depending on ship date and the image used.

This is a busybox shell which presents you with a very minimalistic system. While this has access to many Debian applications, it is important to note that this is not Debian. This environment will allow very fast boot times closer to 2-4 seconds, while Debian takes closer to 30-45 seconds but provides an init system and a more standard environment. As described in the previous section, the kernel and initrd are copied into RAM so any changes to this filesystem are temporary. You can commit changes using the "save" command.

For most development you will want to boot to the Debian filesystem which can be reached by typing "exit" through the serial console, or by relinking the linuxrc script to make the board automatically boot to Debian:

rm linuxrc; ln -s /linuxrc-sdroot /linuxrc; save

The linuxrc-sdroot script will actually mount and boot to the Debian filesystem on the SD or XNAND depending which device you used to boot. You can boot to a different Debian partition by using one of the other linuxrc scripts:

Script	Function
linuxrc-fastboot (default)	Boots immediately to a shell in ramdisk. This will mount whichever boot medium you have selected to /mnt/root/. When you type 'exit', it will boot to that medium.
linuxrc-sdmount	Same as the linuxrc-fastboot script, but will mount and boot the debian partition from SD.
linuxrc-sdroot	Boots immediately to the Debian stored on either SD or NAND depending on which media the SBC was booted from.
linuxrc-sdroot-readonly	Same as linuxrc-sdroot, except it will mount the Debian partition read only while creating a unionfs with a ramdisk. Changes will only happen in memory and not on disk.

Once you have booted to Debian you can force the boot process to stop in the fastboot shell/initd on next bootup with:

touch /fastboot

The small default initrd is only 2Mbyte but there is space for approximately 800 Kbyte of additional user applications. This constraint is important if you are running your application without Debian, but only from the initrd. If you have the Debian partition available you can access that partition under /mnt/root/ to run your application.

The compiled instance of busybox includes several internal commands listed below:

   # /bin/busybox --help
   BusyBox v1.14.2 (2009-08-07 14:43:48 MST) multi-call binary
   Copyright (C) 1998-2008 Erik Andersen, Rob Landley, Denys Vlasenko
   and others. Licensed under GPLv2.
   See source distribution for full notice.
   
   Usage: busybox [function] [arguments]...
      or: function [arguments]...
   
           BusyBox is a multi-call binary that combines many common Unix
           utilities into a single executable.  Most people will create a
           link to busybox for each function they wish to use and BusyBox
           will act like whatever it was invoked as!
   
   Currently defined functions:
           [, [[, ash, basename, cat, chgrp, chmod, chown, chroot, cmp, cp,
           cpio, cttyhack, cut, date, dd, depmod, devmem, df, dirname, dmesg,
           du, echo, egrep, env, expr, false, fdisk, fgrep, find, grep, gunzip,
           gzip, halt, head, hostname, hush, ifconfig, insmod, kill, killall,
           ln, login, ls, lsmod, md5sum, mdev, mkdir, mknod, modprobe, more,
           mount, msh, mv, netstat, ping, pivot_root, poweroff, printf, ps,
           pwd, reboot, rm, rmdir, rmmod, route, rx, sed, setconsole, setsid,
           sh, sleep, stty, sync, tail, tar, telnetd, test, tftp, top, tr,
           true, udhcpc, umount, unzip, usleep, uudecode, uuencode, vi, wget,
           xargs, yes, zcat

Also on the initrd are the TS specific applications: sdctl, ts4300ctl, canctl, and xuartctl. We also provide the ts4300.subr which provides the following functions:

 cvtime()
 usbload()
 sdsave()
 spiflashsave()
 save()
 sd2spiflash()
 spiflash2sd()
 setdiopin()
 getdiopin()
 setrelay()
 setout()
 getin()
 tshelp()
 gettemp()

To use these functions you must source the subr file:

. /ts4300.subr
## or from Debian 
# . /initrd/ts4300.subr
tshelp