On 10/03/2018 03:17 PM, Jens Wiklander wrote:
On Wed, Oct 3, 2018 at 2:27 PM, Jorge Ramirez-Ortiz jramirez@baylibre.com wrote:
I am upstreaming TF-A support for the Renesas R-car gen3 platforms [1].
In order to prevent the boot cpu from being switched off (hotpluged) I am having to work around the fact that OPTEE_OS does not support MIGRATE_INFO_TYPE or MIGRATE_INFO_UP_CPU.
Why should OP-TEE care about that?
the boot cpu boots OP-TEE; when OP-TEE has migration requirements the boot cpu must not be hot-plugged. So OP-TEE in away should care about implementing those interfaces (unless every OP-TEE ever created is guaranteed to have no migration restrictions).
Its SPD at TF-A level [2] returns that the TrustedOS if fully MP aware and has not special requirements for migration.
Isn't that true for upstream OP-TEE?
? but what happens if the user is working with a non-upstream OP-TEE? The way TF-A has been written hard-codes the requirement of an OP-TEE with no migration restrictions.
IMO the code at this level should be generic and always query. why dont you see it this way?
The work around I implemented (patch below and [3]) will query the platform whenever the opteed SPD indicates that it has no migration restrictions (which currently is always)
Is there any work ongoing on OPTEE_OS to support MIGRATE_INFO and update the TF-A SPD or am I missing some fundamental point?
No, there's no work ongoing in this area. Please elaborate on why this is needed.
see the above comments (should I elaborate more? not sure what else to add :))