OpenWrt sysupgrade support

sysupgrade is an OpenWrt invention that allows the rootfs to be updated to another firmware.

The sysupgrade script for the Gateworks products provides:

• the /sbin/sysupgrade script on the target will flash the kernel/rootfs contained in a specified image
• the image contents will be validated via an md5 checksum in the image header
• the kernel and rootfs will be updated (squashfs+jffs2, jffs2 supported, or ubi)
• standard system config files will be retained (saved, then restored) (unless the -n cmdline option is provided)
• the -c command-line argument will save all files on the overlay filesystem

A standard make in the OpenWrt buildroot tree will create a sysupgrade image for your target by default named:

• newport: use the compressed disk image: openwrt-20.06-newport.img.gz
• ventana: use the ubi image: bin/imx6/*-squashfs-nand_*.ubi
• laguna: use the sysupgrade image: bin/<target>/*-sysupgrade.bin

You can find more information about sysupgrade on the OpenWrt wiki ​here

Sysupgrade via command line

Examples:

• Upgrade a 256MB flash device:

  cd /tmp
  wget http://192.168.1.175/openwrt/imx6/gateworks-imx6-ventana-squashfs-nand_normal.ubi
  sysupgrade -v gateworks-imx6-ventana-squashfs-nand_normal.ubi
  

• from a URL:

  sysupgrade -v http://192.168.1.175/openwrt/imx6/gateworks-imx6-ventana-squashfs-nand_normal.ubi
  

Using LuCI Web-Admin

To perform a sysupgrade using the OpenWrt WebGUI, please use an ubi file, such as ​ventana-owrt-20.06-normal.ubi

Go to the top System tab, then the lower tab should be selected as Backup / Flash Firmware.

Under 'Flash new firmware image' please select the ubi from the location on the desktop PC.

In the background, this is what is happening on the serial console

Switching to ramdisk...
[  447.449487] UBIFS: background thread "ubifs_bgt0_0" stops
[  447.519016] UBIFS: un-mount UBI device 0, volume 0
[  447.585743] UBI: detaching mtd2 from ubi0
[  447.591108] UBI: mtd2 is detached from ubi0
ubiformat: mtd2 (nand), size 250609664 bytes (239.0 MiB), 1912 eraseblocks of 131072 bytes (128.0 KiB), min. I/O size 2048 bytes
libscan: scanning eraseblock 1911 -- 100 % complete
ubiformat: 1912 eraseblocks have valid erase counter, mean value is 1
ubiformat: flashing eraseblock 154 -- 100 % complete
ubiformat: formatting eraseblo[  467.802383] UBI: attaching mtd2 to ubi0
ubiformat: formatting eraseblock 1911 -- 100 % complete
[  468.505882] UBI: scanning is finished
[  468.525333] UBI: volume 0 ("rootfs") re-sized from 153 to 1868 LEBs
[  468.532619] UBI: attached mtd2 (name "rootfs", size 239 MiB) to ubi0
[  468.539101] UBI: PEB size: 131072 bytes (128 KiB), LEB size: 126976 bytes
[  468.545937] UBI: min./max. I/O unit sizes: 2048/2048, sub-page size 2048
[  468.552783] UBI: VID header offset: 2048 (aligned 2048), data offset: 4096
[  468.559702] UBI: good PEBs: 1912, bad PEBs: 0, corrupted PEBs: 0
[  468.565719] UBI: user volume: 1, internal volumes: 1, max. volumes count: 128
[  468.572885] UBI: max/mean erase counter: 4/2, WL threshold: 4096, image sequence number: 250308913
[  468.581878] UBI: available PEBs: 0, total reserved PEBs: 1912, PEBs reserved for bad PEB handling: 40
[  468.591156] UBI: background thread "ubi_bgt0d" started, PID 4603
UBI device number 0, total 1912 LEBs (242778112 bytes, 231.5 MiB), available 0 LEBs (0 bytes), LEB size 126976 bytes (124.0 KiB)
[  468.666681] UBIFS: background thread "ubifs_bgt0_0" started, PID 4621
[  468.686194] UBIFS: start fixing up free space
[  469.759179] UBIFS: free space fixup complete
[  469.782548] UBIFS: mounted UBI device 0, volume 0, name "rootfs"
[  469.788572] UBIFS: LEB size: 126976 bytes (124 KiB), min./max. I/O unit sizes: 2048 bytes/2048 bytes
[  469.797786] UBIFS: FS size: 235794432 bytes (224 MiB, 1857 LEBs), journal size 9023488 bytes (8 MiB, 72 LEBs)
[  469.807805] UBIFS: reserved for root: 0 bytes (0 KiB)
[  469.812924] UBIFS: media format: w4/r0 (latest is w4/r0), UUID 58020D53-74F0-4A4C-83AA-B2FB6B08508F, small LPT model
[  469.877200] UBIFS: un-mount UBI device 0, volume 0
[  469.882090] UBIFS: background thread "ubifs_bgt0_0" stops
sysupgrade successful
[  469.904545] imx2-wdt 20bc000.wdog: Device shutdown: Expect reboot!
[  469.910875] reboot: Restarting system

Customizing Sysupgrade

There is a specified set of files that get backed up and restored to the newly upgraded image along with all of UCI. This is configured in /etc/sysupgrade.conf. If you want your init changes to persist across a sysupgrade be sure to configure things properly. You may want to create an OpenWrt package and use UCI configuration to help do that for you.