A recent U-Boot will serve as well to get the board running, and meanwhile the Leap installer got updated to recognise the SD card.
Regarding the supply voltage I can only confirm that a USB power supply with working PD runs fine here after one without PD failed (reboot loops). Beyond that I didn't have to tune anything. The actual voltage is available as VIN6 to the SARADC (Schematics p29, R95132 and R95133 right hs down). The only remaining downside is that the screens stay black, because the DT does not show anything connected to the display engines yet. WiP. I've created an HCL page: https://en.opensuse.org/HCL:ROCK_Pi_5 Torsten
