[RFC PATCH 1/1] dt-bindings: arm: Add scmi_devid property description for SCMI

[Oleksii Moisieiev]

Document scmi_devid property for the devices, using SCMI protocol
to work with clocks/resets/power-domains etc. This property is intended
to set the device id, which should be used to manage device permissions
in the firmware. Device permissions management is descibed in DEN 0056,
Section 4.2.2.10 [0].

This property is useful for the virtualized systems, when several agents
are running on the same platform. Agent term is descibed in Section
4.1.1 [0].

[0] https://developer.arm.com/documentation/den0056/latest

Signed-off-by: Oleksii Moisieiev <oleksii_moisieiev@xxxxxxxx>
---
 .../bindings/firmware/arm,scmi-devid.yaml     | 41 +++++++++++++++++++
 1 file changed, 41 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/firmware/arm,scmi-devid.yaml

diff --git a/Documentation/devicetree/bindings/firmware/arm,scmi-devid.yaml b/Documentation/devicetree/bindings/firmware/arm,scmi-devid.yaml
new file mode 100644
index 000000000000..b0949319e00b
--- /dev/null
+++ b/Documentation/devicetree/bindings/firmware/arm,scmi-devid.yaml
@@ -0,0 +1,41 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+# Copyright 2022 EPAM Systems.
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/firmware/arm,scmi-devid.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: System Control and Management Interface (SCMI) Device ID for permissions
+    handling
+
+maintainers:
+  - Oleksii Moisieiev <oleksii_moisieiev@xxxxxxxx>
+
+description: |
+  SCMI device id property is intended to set the device id, needed to manage
+  the device permissions via SCMI protocol in the firmware. The device Id
+  should match device ids, defined in the firmware so the device permissions
+  can be requested by sending BASE_SET_DEVICE_PERMISSIONS (see 4.2.2.10 of [0]).
+
+  This property is useful on the virtualized systems, when several agents are
+  running on the same time and permissions should be set for the devices,
+  related to different agents.
+
+  [0] https://developer.arm.com/documentation/den0056/latest
+
+properties:
+  scmi_devid:
+    description: Identifier of the device, matching device id, defined in
+      the firmware.
+    $ref: /schemas/types.yaml#/definitions/uint32
+
+additionalProperties: false
+
+examples:
+  - |
+    ohci1: usb@ee0a0000 {
+        /* ... */
+        reg = <0 0xee0a0000 0 0x100>;
+        scmi_devid = <11>;
+        clocks = <&scmi_clock 4>;
+    };
-- 
2.27.0