dt-bindings: rtc: Add Amlogic A4 and A5 RTC

Add documentation describing the Amlogic A4(A113L2) and A5(A113X2) RTC.

Signed-off-by: Yiting Deng <yiting.deng@amlogic.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Xianwei Zhao <xianwei.zhao@amlogic.com>
Link: https://lore.kernel.org/r/20241112-rtc-v6-1-a71b60d2f354@amlogic.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

Documentation/devicetree/bindings/rtc/amlogic,a4-rtc.yaml

@@ -0,0 +1,63 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# Copyright (C) 2024 Amlogic, Inc. All rights reserved
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/rtc/amlogic,a4-rtc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Amlogic A4 and A5 RTC
+
+maintainers:
+  - Yiting Deng <yiting.deng@amlogic.com>
+  - Xianwei Zhao <xianwei.zhao@amlogic.com>
+
+allOf:
+  - $ref: rtc.yaml#
+
+properties:
+  compatible:
+    enum:
+      - amlogic,a4-rtc
+      - amlogic,a5-rtc
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: RTC clock source, available 24M or 32K crystal
+          oscillator source. when using 24M, need to divide 24M into 32K.
+      - description: RTC module accesses the clock of the apb bus.
+
+  clock-names:
+    items:
+      - const: osc
+      - const: sys
+
+  interrupts:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - interrupts
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    apb {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        rtc@8e600 {
+            compatible = "amlogic,a4-rtc";
+            reg = <0x0 0x8e600 0x0 0x38>;
+            clocks = <&xtal_32k>, <&clkc_periphs 1>;
+            clock-names = "osc", "sys";
+            interrupts = <GIC_SPI 131 IRQ_TYPE_EDGE_RISING>;
+        };
+    };