An OpenWrt UBI Installer Image Generator for CreatLentem CLT-R30B1

Warning

This will replace the bootloader (TF-A 2.13, U-Boot 2025.10) and convert the flash layout of the device to an all-in-UBI layout. The installer stores a copy of the previous bootchain in a dedicated UBI volume boot_backup.

Caution

Re-flashing the installer when the device is already using UBI flash layout will erase the previously backed up bootchain, which in most cases would be the vendor/official one.

If you plan to ever go back to the stock firmware, you will need a backup of the vendor bootchain and firmware.

Caution

The installer is meant to be executed only once per device.

Table of Contents

• Script information
• Installing OpenWrt
• Enter recovery mode under OpenWrt

Script information

This script downloads the OpenWrt ImageBuilder to generate a firmware upgrade image compatible with the stock firmware which will automatically carry out the installation. The process involves re-packaging the initramfs image to contain everything necessary for a permanent installation of a replacement Das U-Boot bootloader, ARM TrustedFirmware-A and an OpenWrt recovery (initramfs) image within the NAND flash, plus the installer script itself.

You'll need the below to use the script to generate the installer image:

• All prerequisites of the OpenWrt ImageBuilder
• libfdt-dev
• cmake
• zstd

If you are not interested in building yourself, the pre-built files are available here.

Installing OpenWrt all-in-UBI

1. Ensure your router is running the latest generic OpenWrt firmware. Upgrade it if necessary.

2. Assign IP 192.168.1.254/24 to your computer's Ethernet port

3. Connect Ethernet to the 1GE LAN port

4. Open browser and visit http://192.168.1.1

5. Flash openwrt-[version]-mediatek-filogic-creatlentem_clt-r30b1-ubi-initramfs-recovery-installer.itb via sysupgrade.

6. Once OpenWrt initramfs system comes up, do sysupgrade using openwrt-[version]-mediatek-filogic-creatlentem_clt-r30b1-ubi-squashfs-sysupgrade.itb

Backup stock/vendor bootchain

Connect to the device via SSH and enter the following command:

cat /dev/ubi0_6 | tar xzv -C /tmp

Then, copy the files under /tmp/boot_backup using scp to your computer. These files are needed in case you want to restore the original/vendor firmware. They can also be used in emergency case for reflashing via [UART].

Enter recovery mode under OpenWrt

Using the RESET button:

1. Hold down the "reset" button whilst powering on the device.

2. Release the button once the status LED turns into red.

This will remove any user configuration and allow restoring or upgrading from ssh/http/tftp.

Using PSTORE/ramoops

1. While running the production firmware enter this command in the shell

   echo c > /proc/sysrq-trigger

2. Once the router has rebooted into recovery mode, clear PSTORE to make it reboot into production mode again:

   rm /sys/fs/pstore/*

This keep user configuration but still allow restoring or upgrading from ssh/http/tftp.