dt-bindings: fu540: prci: convert PRCI bindings to json-schema

FU540-C000 SoC from SiFive has a PRCI block, here we convert
the device tree bindings from txt to YAML.
Signed-off-by: Sagar Kadam <sagar.kadam@sifive.com>
Link: https://lore.kernel.org/r/1601393531-2402-2-git-send-email-sagar.kadam@sifive.comSigned-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/clock/sifive/fu540-prci.txt

-SiFive FU540 PRCI bindings
-
-On the FU540 family of SoCs, most system-wide clock and reset integration
-is via the PRCI IP block.
-
-Required properties:
-- compatible: Should be "sifive,<chip>-prci".  Only one value is
-	supported: "sifive,fu540-c000-prci"
-- reg: Should describe the PRCI's register target physical address region
-- clocks: Should point to the hfclk device tree node and the rtcclk
-          device tree node.  The RTC clock here is not a time-of-day clock,
-	  but is instead a high-stability clock source for system timers
-	  and cycle counters.
-- #clock-cells: Should be <1>
-
-The clock consumer should specify the desired clock via the clock ID
-macros defined in include/dt-bindings/clock/sifive-fu540-prci.h.
-These macros begin with PRCI_CLK_.
-
-The hfclk and rtcclk nodes are required, and represent physical
-crystals or resonators located on the PCB.  These nodes should be present
-underneath /, rather than /soc.
-
-Examples:
-
-/* under /, in PCB-specific DT data */
-hfclk: hfclk {
-	#clock-cells = <0>;
-	compatible = "fixed-clock";
-	clock-frequency = <33333333>;
-	clock-output-names = "hfclk";
-};
-rtcclk: rtcclk {
-	#clock-cells = <0>;
-	compatible = "fixed-clock";
-	clock-frequency = <1000000>;
-	clock-output-names = "rtcclk";
-};
-
-/* under /soc, in SoC-specific DT data */
-prci: clock-controller@10000000 {
-	compatible = "sifive,fu540-c000-prci";
-	reg = <0x0 0x10000000 0x0 0x1000>;
-	clocks = <&hfclk>, <&rtcclk>;
-	#clock-cells = <1>;
-};

Documentation/devicetree/bindings/clock/sifive/fu540-prci.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# Copyright (C) 2020 SiFive, Inc.
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/sifive/fu540-prci.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SiFive FU540 Power Reset Clock Interrupt Controller (PRCI)
+
+maintainers:
+  - Sagar Kadam <sagar.kadam@sifive.com>
+  - Paul Walmsley  <paul.walmsley@sifive.com>
+
+description:
+  On the FU540 family of SoCs, most system-wide clock and reset integration
+  is via the PRCI IP block.
+  The clock consumer should specify the desired clock via the clock ID
+  macros defined in include/dt-bindings/clock/sifive-fu540-prci.h.
+  These macros begin with PRCI_CLK_.
+
+  The hfclk and rtcclk nodes are required, and represent physical
+  crystals or resonators located on the PCB.  These nodes should be present
+  underneath /, rather than /soc.
+
+properties:
+  compatible:
+    const: sifive,fu540-c000-prci
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: high frequency clock.
+      - description: RTL clock.
+
+  clock-names:
+    items:
+      - const: hfclk
+      - const: rtcclk
+
+  "#clock-cells":
+    const: 1
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - "#clock-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    prci: clock-controller@10000000 {
+      compatible = "sifive,fu540-c000-prci";
+      reg = <0x10000000 0x1000>;
+      clocks = <&hfclk>, <&rtcclk>;
+      #clock-cells = <1>;
+    };