Power & Source of Big Ideas

Hi all in the forum
Is it possible to build a realtime kernel which runs on the RK3399 nanopi M4 platform?
If it is, where may I find instructions on how to do that?
Hi all,
because of difficult to access SD slot in our product equipped with nanopi M1 plus, is there any possibility to configure U-boot to boot from USB bootable stick instead of sd card?
I'm looking for either a permanent setup or a transient once boot has been stopped by pressing space bar.