dt-bindings: soc: socionext: Add UniPhier AHCI glue layer

Add DT binding schema for components belonging to the platform-specific
AHCI glue layer implemented in UniPhier SoCs.

This AHCI glue layer works as a sideband logic for the host controller,
including core reset, PHYs, and some signals to the controller.
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20221213082449.2721-18-hayashi.kunihiko@socionext.comSigned-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/soc/socionext/socionext,uniphier-ahci-glue.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/soc/socionext/socionext,uniphier-ahci-glue.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Socionext UniPhier SoC AHCI glue layer
+
+maintainers:
+  - Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
+
+description: |+
+  AHCI glue layer implemented on Socionext UniPhier SoCs is a sideband
+  logic handling signals to AHCI host controller inside AHCI component.
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - socionext,uniphier-pro4-ahci-glue
+          - socionext,uniphier-pxs2-ahci-glue
+          - socionext,uniphier-pxs3-ahci-glue
+      - const: simple-mfd
+
+  reg:
+    maxItems: 1
+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 1
+
+  ranges: true
+
+patternProperties:
+  "^reset-controller@[0-9a-f]+$":
+    $ref: /schemas/reset/socionext,uniphier-glue-reset.yaml#
+
+  "phy@[0-9a-f]+$":
+    $ref: /schemas/phy/socionext,uniphier-ahci-phy.yaml#
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    sata-controller@65700000 {
+        compatible = "socionext,uniphier-pxs3-ahci-glue", "simple-mfd";
+        reg = <0x65b00000 0x400>;
+        #address-cells = <1>;
+        #size-cells = <1>;
+        ranges = <0 0x65700000 0x100>;
+
+        reset-controller@0 {
+            compatible = "socionext,uniphier-pxs3-ahci-reset";
+            reg = <0x0 0x4>;
+            clock-names = "link";
+            clocks = <&sys_clk 28>;
+            reset-names = "link";
+            resets = <&sys_rst 28>;
+            #reset-cells = <1>;
+        };
+
+        phy@10 {
+            compatible = "socionext,uniphier-pxs3-ahci-phy";
+            reg = <0x10 0x10>;
+            clock-names = "link", "phy";
+            clocks = <&sys_clk 28>, <&sys_clk 30>;
+            reset-names = "link", "phy";
+            resets = <&sys_rst 28>, <&sys_rst 30>;
+            #phy-cells = <0>;
+        };
+    };