arm64: Hook up efi_rt_arch_call in efirt.ko

[jhb]

Summary

Note that this requires marking efi_rt_fault as a non-preemptible
local symbol.

Co-authored-by: Jessica Clarke <[e-mail]>
Obtained from: CheriBSD
Fixes: d7f930b80e89 ("arm64: Implement efi_rt_arch_call")

[andrew]

sys/arm64/arm64/efirt_support.S

99

sys/modules/efirt/Makefile

15

Is this needed? We only build this module on arm64 and amd64.

[jhb]

sys/modules/efirt/Makefile

15

I think there is a desire to have EFI on RISC-V, so leaving this MD might be prudent.

[imp]

sys/modules/efirt/Makefile

15

Maybe just make it unconditional then. Stubs for this one routine are trivial.

[jhb]

Fix LEND

[andrew]

sys/modules/efirt/Makefile

15

I would hope new architectures would implement the fault safe efi_rt_arch_call so at some point we could remove efi_rt_arch_call_nofault if we decided it was no longer useful.

[imp]

sys/modules/efirt/Makefile

15

Right.
We also have to implement PA != VA for these calls for LinuxBoot to work since Linux sers that up and we are stuck with it.

[jhb]

sys/modules/efirt/Makefile

15

CHERI can't yet have a nofault variant until we have a CHERI-aware firmware since kernel fault handlers don't work. But I could remove this .if I guess if you feel strongly.

[jhb]

Drop an .if