Hi Akshay,

We've had an internal discussion and here's a digest (Marc and others, please chime in if required):

-Arm doesn't plan to implement FF-A notifications in the EL3 SPMC. Partner contributions are welcome.

-There are WIP changes [1] that may be of interest. Note, if those progress, final changes may support the spec only partially (e.g. no support for per vCPU notifications).

-The observation about EL3 SPMC returning FF-A v1.2 support per FFA_VERSION [2] may have to be fixed indeed. It should more likely return v1.1 with limitations that would have to be documented similarly to how the OP-TEE SPMC does [3].

-For the record, admitted this applies to recent chipsets implementing Armv8.4 FEAT_SEL2, Hafnium/S-EL2 SPMC implements the full FF-A notifications support [4].

Regards,

Olivier.

[1] https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/26591/

[2] https://git.trustedfirmware.org/plugins/gitiles/TF-A/trusted-firmware-a/+/refs/heads/master/services/std_svc/spm/el3_spmc/spmc_main.c#717

[3] https://optee.readthedocs.io/en/latest/architecture/spmc.html#ff-a-compliance

[4] https://hafnium.readthedocs.io/en/latest/secure-partition-manager/secure-partition-manager.html#notifications

From: Belsare, Akshay via TF-A <tf-a@lists.trustedfirmware.org>
Sent: 17 September 2024 10:01
To: Marc Bonnici <Marc.Bonnici@arm.com>; tf-a@lists.trustedfirmware.org <tf-a@lists.trustedfirmware.org>
Cc: Simek, Michal <michal.simek@amd.com>; Nagal, Amit <amit.nagal@amd.com>; Bollapalli, Maheedhar Sai <MaheedharSai.Bollapalli@amd.com>; Gudipalli, Sugadeesh <sugadeesh.gudipalli@amd.com>
Subject: [TF-A] TF-A EL3 SPMC upgrade to FF-A Spec v1.2

Hi Marc,

In TF-A, the FF-A version is currently set to v1.2, but I am unable to find the corresponding implementation for EL3 SPMC configuration.

I'm particularly interested in the support for FF-A Notification Mechanism. Could you please provide the timeline for when this will be added to the TF-A EL3 SPMC configuration?

Thank You!

Akshay Belsare