Second stage bootloader in TF-M/MCUBoot

[Nano-HK]

Hey!

I'm been digging into documentation regarding implementation of second stage in MCUBoot - this is based on having secure immutable first stage bootloader.

TF-M documentation mentions briefly how MCUBoot together with TF-M can be used to create secure boot with second stage. Thus, the steps covered in the documentation doesn't really touch on how to build an example with second stage bootloader.

Is there any sample/example or approach I can do to create secure boot with second stage bootloader?
Would appreciate any help!

Regards,
Nano