[PATCH 2/5] dt-bindings: firmware: Add RPMI performance service bindings

[Joshua Yeong]

Add device tree bindings for the RPMI performance service group based
controller for the supervisor software.

The RPMI performance service group is defined by the RISC-V Platform
Management Interface (RPMI) specification.

Signed-off-by: Joshua Yeong <joshua.yeong at starfivetech.com>
---
 .../firmware/riscv,rpmi-performance.yaml      | 62 +++++++++++++++++++
 1 file changed, 62 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/firmware/riscv,rpmi-performance.yaml

diff --git a/Documentation/devicetree/bindings/firmware/riscv,rpmi-performance.yaml b/Documentation/devicetree/bindings/firmware/riscv,rpmi-performance.yaml
new file mode 100644
index 000000000000..61adf6b1bed8
--- /dev/null
+++ b/Documentation/devicetree/bindings/firmware/riscv,rpmi-performance.yaml
@@ -0,0 +1,62 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/firmware/riscv,rpmi-performance.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RISC-V RPMI performance service group based cpufreq controller
+
+maintainers:
+  - Joshua Yeong <joshua.yeong at starfivetech.com>
+
+description: |
+  The RISC-V Platform Management Interface (RPMI) [1] defines a modular and
+  extensible messaging protocol for platform management functions. The supervisor
+  software can send and receive RPMI messages via SBI MPXY extension [2]
+  or via a dedicated supervisor-mode RPMI transport.
+
+  The RPMI specification [1] defines performance service group (performance
+  domain) for accessing and controlling platform-managed performance-related
+  resources, as implemented by a platform microcontroller. Supervisor software
+  can interact with the RPMI performance service group through an SBI MPXY
+  channel or through a dedicated supervisor-mode RPMI transport.
+
+  ===========================================
+  References
+  ===========================================
+
+  [1] RISC-V Platform Management Interface (RPMI) v1.0 (or higher)
+      https://github.com/riscv-non-isa/riscv-rpmi/releases
+
+  [2] RISC-V Supervisor Binary Interface (SBI) v3.0 (or higher)
+      https://github.com/riscv-non-isa/riscv-sbi-doc/releases
+
+properties:
+  compatible:
+    description:
+      Intended for use by the supervisor software.
+    const: riscv,rpmi-performance
+
+  mboxes:
+    maxItems: 1
+    description:
+      Mailbox channel of the underlying RPMI transport or SBI message proxy channel.
+
+  "#performance-domain-cells":
+    const: 1
+
+required:
+  - compatible
+  - mboxes
+  - "#performance-domain-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    performance: rpmi-performance {
+        compatible = "riscv,rpmi-performance";
+        mboxes = <&mpxy_mbox 0x1001 0x0>;
+        #performance-domain-cells = <0x01>;
+    };
+...
-- 
2.43.0