dt-bindings: watchdog: Add watchdog for StarFive JH7100 and JH7110

Add bindings to describe the watchdog for the StarFive JH7100/JH7110 SoC.
And Use JH7100 as first StarFive SoC with watchdog.
Signed-off-by: Xingyu Wu <xingyu.wu@starfivetech.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230314132437.121534-2-xingyu.wu@starfivetech.comSigned-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

Documentation/devicetree/bindings/watchdog/starfive,jh7100-wdt.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/watchdog/starfive,jh7100-wdt.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: StarFive Watchdog for JH7100 and JH7110 SoC
+
+maintainers:
+  - Xingyu Wu <xingyu.wu@starfivetech.com>
+  - Samin Guo <samin.guo@starfivetech.com>
+
+description:
+  The JH7100 and JH7110 watchdog both are 32 bit counters. JH7100 watchdog
+  has only one timeout phase and reboots. And JH7110 watchdog has two
+  timeout phases. At the first phase, the signal of watchdog interrupt
+  output(WDOGINT) will rise when counter is 0. The counter will reload
+  the timeout value. And then, if counter decreases to 0 again and WDOGINT
+  isn't cleared, the watchdog will reset the system unless the watchdog
+  reset is disabled.
+
+allOf:
+  - $ref: watchdog.yaml#
+
+properties:
+  compatible:
+    enum:
+      - starfive,jh7100-wdt
+      - starfive,jh7110-wdt
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: APB clock
+      - description: Core clock
+
+  clock-names:
+    items:
+      - const: apb
+      - const: core
+
+  resets:
+    items:
+      - description: APB reset
+      - description: Core reset
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - resets
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    watchdog@12480000 {
+        compatible = "starfive,jh7100-wdt";
+        reg = <0x12480000 0x10000>;
+        clocks = <&clk 171>,
+                 <&clk 172>;
+        clock-names = "apb", "core";
+        resets = <&rst 99>,
+                 <&rst 100>;
+    };