Configuring the Bootloader

Change the Device Tree

By default, U-Boot loads a device tree binary (dtb) file named oftree during boot. The oftree file is a copy of k3-am62p5-phyflex-libra-rdk.dts. This portion of the guide will instruct how to change U-boot to load different device trees.

Power on the board and press any key to stop autoboot when prompted by the Bootloader.
Use the following command to list the available file’s within the boot media’s Boot partition (this is typically where binaries used for boot are stored):

uboot:~# ls mmc 1:1
 22311424   Image
     2466   boot.scr.uimg
    67368   k3-am62p5-phyflex-libra-rdk.dtb
    67368   oftree
       37   overlays.txt
  3784287   ti-boot-container.img
   294230   tiboot3.bin
  1480343   tispl.bin
  1162847   u-boot.img

9 file(s), 0 dir(s)

We can check which file is the active device tree like so:
```
uboot:~# printenv fdtfile
```

Change the default device tree.

uboot:~# setenv fdtfile <dtb name>
uboot:~# saveenv
uboot:~# boot

U-boot will now load the dtb file named <dtb name> automatically during subsequent boots (just replace it with the appropriate file name when you run the command).

Reset the U-Boot Environment to Default Settings

In order to revert the U-Boot environment back to its original settings, run the following:

uboot:~# env default -f -a
uboot:~# saveenv
uboot:~# boot

Note

When booting from the SD card, if you have saved changes to the environment using saveenv, the changes may persist across flashes of the SD card. It is a good idea to default your environment after flashing.