Re: [PATCH v9 1/7] firmware: smccc: Add an Arm SMCCC bus

On Fri, Sep 04, 2026 at 03:27:27PM +0100, Sudeep Holla wrote:

quoted

IMHO to lean into the bus design I would have a discovery SMCCC that
returns a list of supported ABIs, something like (spec, spec version,
ABI, FID, feature supported bitmap).  There could be overlaps if the
FW supports several ABI incompatible versions, like RSI v1 and RSI v2.

But then we will have to wait for that discovery SMCCC ABI first and that
mean how will it work on existing deployed systems ? But I like the idea.

Oh, I wasn't saying to wait for anything. This is good enough as is.

I was suggesting a next step to make this even better and solve some
of the real problem the ecosystem feels with the FW/kernel ABI.

the software that purely relies on feature bits. So a big yes for that
idea and I think some specs and in some form are doing it. I can't
recall specific but I have seen it. We just need push only for that
in future specs.

I was advocating the approach of a discovery spec that codifies
exactly how all this should work. So each team writing a new spec
doesn't have to reinvent it.

Jason