I'm working on getting a compute module working with Yocto using U-Boot
as bootloader, which mostly works thanks to previous work to get RPi 5
working.
However I'm running into a strange issue: if I turn on the CM5 without
the debug UART (which requires soldering a header onto the CM5)
attached, the Pi doesn't boot beyond showing the submarine splash
screen, if I boot it with the console attached it autoboots correctly.
If I attach the UART after the boot halted and press enter I get a
U-Boot console, and giving the boot command boots it normally.
And setting bootdelay=-2 in the env allows it to correctly boot.
Which leads me to believe there is perhaps a spurious input registered
by U-Boot which interrupts autobooting.
Is there a command that allows me to extract why U-Boot didn't continue
autobooting?
And anyone have a hint how this could perhaps be fixed in a more elegant
way (allowing interruptable autoboot).
The hardware I'm testing on is the CM5 devkit, I needed to make small
changes to yocto to get it working:
https://github.com/agherzan/meta-raspberrypi/pull/1397
No changes were needed in U-Boot to get it to boot
Thanks,
Gijs
