dt-bindings: reset: microchip sparx5 reset driver bindings

Document the Sparx5 reset device driver bindings

The driver uses a syscon and an IO range on sparx5 for access to
the reset control and the reset status.

Sparx5 will no longer use the existing Ocelot chip reset driver, but use
this new switch reset driver as it has the reset controller interface that
allows the first client to perform the reset on behalf of all the Sparx5
component drivers.
Signed-off-by: Steen Hegelund <steen.hegelund@microchip.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

Documentation/devicetree/bindings/reset/microchip,rst.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/reset/microchip,rst.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: Microchip Sparx5 Switch Reset Controller
+
+maintainers:
+  - Steen Hegelund <steen.hegelund@microchip.com>
+  - Lars Povlsen <lars.povlsen@microchip.com>
+
+description: |
+  The Microchip Sparx5 Switch provides reset control and implements the following
+  functions
+    - One Time Switch Core Reset (Soft Reset)
+
+properties:
+  $nodename:
+    pattern: "^reset-controller@[0-9a-f]+$"
+
+  compatible:
+    const: microchip,sparx5-switch-reset
+
+  reg:
+    items:
+      - description: global control block registers
+
+  reg-names:
+    items:
+      - const: gcb
+
+  "#reset-cells":
+    const: 1
+
+  cpu-syscon:
+    $ref: "/schemas/types.yaml#/definitions/phandle"
+    description: syscon used to access CPU reset
+
+required:
+  - compatible
+  - reg
+  - reg-names
+  - "#reset-cells"
+  - cpu-syscon
+
+additionalProperties: false
+
+examples:
+  - |
+    reset: reset-controller@11010008 {
+        compatible = "microchip,sparx5-switch-reset";
+        reg = <0x11010008 0x4>;
+        reg-names = "gcb";
+        #reset-cells = <1>;
+        cpu-syscon = <&cpu_ctrl>;
+    };
+