Wouldn't that be a uboot issue?
Perhaps you could piggy-back on this effort.
https://www.reddit.com/r/OrangePI/comments/1buzts4/uboot_v20...
https://www.reddit.com/r/OrangePI/comments/1buzts4/uboot_v20...
It's an archlinux PKGBUILD that applies a couple patches for the device drivers and HDMI. This can probably be repurposed to build on any linux distro. Obviously flash your firmware with caution, but it's been booting from SPI to NVME without any issue for a while now.
If there is more interest in this, I can fully flesh this out.
The board boots Armbian fine with nothing connected to the serial port.
[1] https://github.com/Joshua-Riek/ubuntu-rockchip/issues/1073