Re: [PATCH v4 2/8] firmware: smccc: Add support for Live Firmware Activation (LFA)

[Sudeep Holla <sudeep.holla@kernel.org>]

On Wed, Sep 23, 2026 at 01:46:56PM +0200, Andre Przywara wrote:
> On 9/21/26 17:32, Sudeep Holla wrote:
> > 
> > DEN0147, Section 2.1.2, says that the caller must determine that
> > the SMCCC version is at least 1.2 before calling LFA_VERSION.  The generic
> > SMCCC probing path only checks that a conduit exists before invoking this
> > function ID. That could break our SMCCC bus logic. Assuming the firmware
> > can cope up, it is always good to check the SMCCC version >=v1.2 in the
> > probe which is not done currently.
> 
> So as said above, I am checking this in lfa_smccc_probe() now. If I get you
> right, then that's the right place to do? Or are you suggesting we should
> move that check into the SMCCC bus code? I think the version call is
> compliant with the SMCCC v1.0 calling convention, so should be safe to call
> in any case?
> 

I hope so. I was just thinking out loud here. My earlier comment to check
for SMCCC v1.2 before using LFA_VERSION conflicts with what SMCCC logic
as is. But yes it should be compliant, I was just thinking how one statement
from the spec I used to request you to add a check in probe conflict here.

Worst case we can add version based addition in that SMCCC device addition
if required in the future, shouldn't be a big deal.

-- 
Regards,
Sudeep