dt-bindings: soc: add loongson-2 chipid

Add the Loongson-2 SoC chipid binding with DT schema format using
json-schema.
Signed-off-by: Yinbo Zhu <zhuyinbo@loongson.cn>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20221111054201.18528-2-zhuyinbo@loongson.cn'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Documentation/devicetree/bindings/hwinfo/loongson,ls2k-chipid.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/hwinfo/loongson,ls2k-chipid.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Loongson-2 SoC ChipID
+
+maintainers:
+  - Yinbo Zhu <zhuyinbo@loongson.cn>
+
+description: |
+  Loongson-2 SoC contains many groups of global utilities register
+  blocks, of which the ChipID group registers record SoC version,
+  feature, vendor and id information.
+
+properties:
+  compatible:
+    const: loongson,ls2k-chipid
+
+  reg:
+    maxItems: 1
+
+  little-endian: true
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    chipid: chipid@1fe00000 {
+        compatible = "loongson,ls2k-chipid";
+        reg = <0x1fe00000 0x3ffc>;
+        little-endian;
+    };

MAINTAINERS

@@ -12012,6 +12012,7 @@ LOONGSON-2 SOC SERIES GUTS DRIVER
 M:	Yinbo Zhu <zhuyinbo@loongson.cn>
 L:	loongarch@lists.linux.dev
 S:	Maintained
+F:	Documentation/devicetree/bindings/hwinfo/loongson,ls2k-chipid.yaml
 F:	drivers/soc/loongson/loongson2_guts.c
 
 LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI)