@hijax_pl You need to install the rockpi4-dtbo package from the radxa apt repo to get /boot/hw_intfc.conf (and the corresponding overlay files).
update: it appears that you also need to install rockpi4b-rk-u-boot-latest and run “sudo /usr/local/sbin/rockpi4b_upgrade_bootloader.sh” then reboot to get the overlays to work.