Help needed: EFI debug

[Michael Lawnick]

Hi,

I am trying to printf-debug EFI execution triggered by Linux call.
Specifically I remove a persistent variable via Linux console and want
to follow execution. Without any printf() this works fine. I need this
to refine existing implementation of saving variables to SPI flash.

While printf() works in U-Boot startup context it leads to crash when
EFI function was called from Linux. Same for putc().
Next I tried efi_st_printf() but this already crashes in U-Boot startup
context.
How do you achieve printf() debugging in this scenario?
Which initialization steps are required to get efi_st_printf() working
outside self_test context?

TIA & KR
Michael