View source for Filesystem from flash script

While there is no issue in executing filesystem_from_usb when booted from SD (provided there are no flash partitions mounted), further preparation is required in order to successfully boot from eMMC/NAND, and use the USB update functionality to update the flash.  A USB device is required to have the the Debian distribution on the first partition and a specific set of steps in the "tsinit" script - this ensures that all flash partitions are safely unmounted and the necessary tools are available.  See the [[#From_USB_storage_device_.28USB_update_mechanism.29|initramfs USB scripting]] section for more information on setting up the "tsinit" script.

Using a linux host PC, format a USB drive with the first partition (min. 2GB) formatted ext2/3.  Download the [https://files.embeddedTS.com/ts-arm-sbc/ts-7670-linux/distributions/ts7670_7400v2-debian-wheezy-arm-latest.tar.bz2 distribution tarball] and extract it to first partition of the USB drive.

Next, set up the "tsinit" file with the following script outline:
<source lang="bash">
#!/bin/sh

#We only need unmount /mnt/root and use USB if booted from NAND/eMMC
if [ "$bootmode" == "0x1" ]; then
  killall mdnsd >/dev/null #Required to cleanly umount /etc
  sleep 1
  if [ -e /dev/mtd0 ]; then
    umount /mnt/root/ts
  fi
  umount /etc
  umount /mnt/root

  mount -obind /mnt/usbdev /mnt/root
  mount -obind /mnt/root/etc /etc/
fi

echo ""
source /ts.subr
tshwctl --greenledon --redledon
echo "Flashing kernel"
kernel_from_usb >/dev/null 2>&1
if [ "$?" != "0" ]; then
  echo "Failed flashing kernel"
  tshwctl --greenledoff
  while true; do tshwctl --redledon; sleep .5; tshwctl --redledoff; sleep .5 ; done &
  return 1
fi
echo "Flashing filesystem"
eval `filesystem_from_usb`
if [ "$prog_ok" != "1" ] ; then
  echo "Failed flashing filesystem"
  tshwctl --greenledoff
  while true; do tshwctl --redledon; sleep .5; tshwctl --redledoff; sleep .5 ; done &
  return 1
fi

#We only need unmount /mnt/root and use USB if booted from NAND
if [ "$bootmode" == "0x1" ]; then
  umount /etc
  umount /mnt/root
fi

echo "Done"
while true; do tshwctl --greenledon; sleep .5; tshwctl --greenledoff; sleep .5 ; done &
</source>