RiscV SBI incompatibilities?

[Martin Husemann <martin@NetBSD.org>]

Hi folks,

maybe I tried something stupid, but it felt like a good idea at first.

I am updating my VisionFive 2 board from an oldish installation with
U-Boot 2024.10.

To have as few moving parts as possible, I build 2026.10 with the same SBI
that I had lying around from the original 2024.10 build, which happend
to be OpenSBI 1.4.

This failed spectacularily: most sbc_* calls for HSM fail with 
-3 (SBI_ERR_INVALID_PARAM).

A few calls worked, like sbi_hart_start() and sbi_hart_get_status(),
which told me the hartids I was using were valid, but then doing
e.g. sbi_send_ipi() or sbi_remote_sfence_vma() failed.

Does this ring a bell? Is it expected? Did I overlook a "minimal SBI version
1.X" somewhere?

Martin