I just set up my new HC-4 with Armbian 23.02.2 Bullseye following the instructions at https://www.armbian.com/odroid-hc4/
Unfortunately, I have exactly the same problem as themole.
On the installed kernel 6.1.11-meson64, I don't see the mtd-devices.
I downgraded to 5.10.16-meson64. Still no mtd-devices.
I started the HC-4 without pressing the button, in the hope to apply the method "Petitboot Console Method" from the instructions. But then, nothing happens. The screen stays dark.
Unlike themole, I don't have the USB-serial-cable around that I could use. So please, could you give me a hint how I can get rid of petitboot. Is there a specific kernel version I should boot? Or a specific image for the SD-card that I should use?
Here is the output of armbianmonitor -u (on 6.1.11-meson64 kernel):
https://paste.armbian.com/sapizoqiva