On Tue, Dec 30, 2025 at 5:10 AM Sumit Garg sumit.garg@kernel.org wrote:
On Mon, Dec 29, 2025 at 05:25:30PM -0600, Rob Herring wrote:
On Wed, Dec 17, 2025 at 04:39:12PM +0100, Arnaud Pouliquen wrote:
Add a device tree binding for the TEE-based remote processor control service implemented as an OP-TEE Trusted Application identified by UUID 80a4c275-0a47-4905-8285-1486a9771a08.
The TEE service node is a child of the "linaro,optee-tz" firmware node and acts as a container for remoteproc devices that are controlled via TEE.
Is this generic for any remoteproc device or just ST's remoteproc. Looks like the latter to me.
That's true, the DT description of the remoteproc subnode is very specific to the vendor which in this case is ST.
In addition, the "linaro,optee-tz" binding is updated to specify the '#address-cells' and '#size-cells' values used for child TEE service nodes.
I'm pretty sure I already rejected per service/app child nodes for OP-TEE when its binding was submitted.
That was the reason to have discoverable TEE bus in first place and I have been motivating people to dynamically discover firmware properties rather than hardcoding in the DT.
If we do need something in DT to define some resources, then can't we have some sort of standard/common communications channel? I don't care to see some sort of free-for-all where we have every vendor doing their own thing. OP-TEE needs to standarize this.
I suppose this requires a wider scope work as you can see the DT resource dependence from here [1]. By standardize communication channel, do you mean to say if adding an alternative backend to fwnode for TEE in parallel to DT, ACPI or swnode is the way to go for discovering fw properties?
No, not at all.
Or do you have any other suggestion here?
What I mean is why doesn't the TEE define the communication channel (mailbox+shmem and notification interrupt) rather than each TEE app?
More generally, is having TEE apps depending on random DT resources really a box we want to open? Is the next thing going to be a TEE clock/reset/gpio/power provider? Where do we draw the line?
Rob