[U-Boot] Getting the reboot/reset reason through to the kernel

[Chris Packham]

Hi List,

Sorry for a vague general post.

I know that a number of SoCs have a reset reason register so that they
can distinguish between power-on reset vs reset line input vs watchdog
timer etc.

Is there any standard thing in u-boot that looks at these to "do
stuff" e.g. to put peripherals through a manual reset or skip certain
parts of init.

Is there any standard way of getting this to the Linux kernel and
ultimately to userspace to generate a log?

Searching for "linux reboot reason" naturally leads to a zillion
results of people wanting to know why their server/laptop crashed so
my duckduckgo-fu (yeah I'm trying to make that a thing) is failing me.

Thanks,
Chris