Upgrade from Kernel Space

Copy the U-Boot debian package to your board and install it directly.

$ sudo dpkg -i linux-u-boot-vim4-vendor_xxxx-2019.01_arm64.deb
$ sync
$ sudo reboot

Upgrade from U-Boot Console

You need to setup Seria Debug Tool first, then follow the steps bellow to upgrade the U-Boot:

• Power on the board and hit SPACE key to enter the U-Boot command line
• Copy u-boot.bin.signed into an SD card or thumbdrive which is located at build/u-boot/fip/_tmp/u-boot.bin.signed
• Insert the SD card or thumbdrive into the board
• Execute the following commands to upgrade U-Boot

  kvim4# usb_update bootloader u-boot.bin.signed
  kvim4# reboot