Re: [PATCH v3 0/1] dt-bindings: Add device-perms property description
From: Stefano Stabellini
Date: Thu Jun 02 2022 - 21:19:28 EST
On Wed, 1 Jun 2022, Rob Herring wrote:
> On Thu, May 05, 2022 at 11:23:50AM +0000, Oleksii Moisieiev wrote:
> > Introduce device-perms property which is intended to set the device
> > permissions for the System Management interfaces.
> > An example of this interface is SCMI (System Control and Management
> > Interface) which controls clocks/power-domains/resets etc from the
> > Firmware. This property sets the device_id to set the device permissions
> > for the Fimware using BASE_SET_DEVICE_PERMISSIONS message (see 4.2.2.10 of [0]).
>
> Is that an exhaustive list of controls? Seems like there would be a
> GET_DEVICE_PERMISSIONS.
>
> > Device permissions management described in DEN 0056, Section 4.2.2.10 [0].
> > Given parameter should set the device_id, needed to set device
> > permissions in the Firmware.
> > This property is used by trusted Agent to set permissions for the devices,
> > passed-through to the non-trusted Agents. Trusted Agent will use device-perms to
> > set the Device permissions for the Firmware (See Section 4.2.2.10 [0]
> > for details).
> > Agents concept is described in Section 4.2.1 [0].
>
> As I said on the call discussing this, this looks very similar to other
> proposals wanting to control or check permissions on devices handled by
> some provider. While the consumer of the binding is different in various
> proposals, that doesn't really matter from a DT perspective. DT is just
> describing some type of connection between nodes. So I'm looking for
> collaboration here with folks that have made prior proposals. To put it
> another way, for a new common binding like this, I want to see more than
> one user.
Do you have a pointer to another similar proposal or the name of someone
that might be interested and might be having a second use-case for this?