This is an issue for both “official” images here https://github.com/radxa-build/radxa-cm3-io/releases/tag/20221001-0126
1) No /boot/uEnv.txt
radxa-cm3-io-debian-bullseye-xfce4-arm64-20221001-0439-gpt.img.xz
2) No /boot/uEnv.txt
radxa-cm3-io-ubuntu-focal-server-arm64-20221001-0229-gpt.img.xz
Even worse, the instructions in /boot/config.txt don’t seem to work. Am I supposed to put my compiled dtbo in /boot/dtbs/$(uname -r)/rockchip/overlay/ ? Then I run /usr/local/sbin/update_extlinux.sh as instructed? My dtbo file is gone.
Can anyone please help? I will pay. Please DM me.
Ref: No /boot/uEnv.txt file after flash the ubuntu img to sd card