dt-bindings: display: convert Arm Komeda to DT schema

The Arm Komeda (aka Mali-D71) is a display controller that scans out a
framebuffer and hands a signal to a digital encoder to generate a DVI
or HDMI signal. It supports up to two pipelines, each frame can be
composed of up to four layers.

Convert the existing DT binding to DT schema.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Signed-off-by: NRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220506140533.3566431-12-andre.przywara@arm.com

Documentation/devicetree/bindings/display/arm,komeda.txt

-Device Tree bindings for Arm Komeda display driver
-
-Required properties:
-- compatible: Should be "arm,mali-d71"
-- reg: Physical base address and length of the registers in the system
-- interrupts: the interrupt line number of the device in the system
-- clocks: A list of phandle + clock-specifier pairs, one for each entry
-    in 'clock-names'
-- clock-names: A list of clock names. It should contain:
-      - "aclk": for the main processor clock
-- #address-cells: Must be 1
-- #size-cells: Must be 0
-- iommus: configure the stream id to IOMMU, Must be configured if want to
-    enable iommu in display. for how to configure this node please reference
-        devicetree/bindings/iommu/arm,smmu-v3.txt,
-        devicetree/bindings/iommu/iommu.txt
-
-Required properties for sub-node: pipeline@nq
-Each device contains one or two pipeline sub-nodes (at least one), each
-pipeline node should provide properties:
-- reg: Zero-indexed identifier for the pipeline
-- clocks: A list of phandle + clock-specifier pairs, one for each entry
-    in 'clock-names'
-- clock-names: should contain:
-      - "pxclk": pixel clock
-
-- port: each pipeline connect to an encoder input port. The connection is
-    modeled using the OF graph bindings specified in
-    Documentation/devicetree/bindings/graph.txt
-
-Optional properties:
-  - memory-region: phandle to a node describing memory (see
-    Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt)
-    to be used for the framebuffer; if not present, the framebuffer may
-    be located anywhere in memory.
-
-Example:
-/ {
-	...
-
-	dp0: display@c00000 {
-		#address-cells = <1>;
-		#size-cells = <0>;
-		compatible = "arm,mali-d71";
-		reg = <0xc00000 0x20000>;
-		interrupts = <0 168 4>;
-		clocks = <&dpu_aclk>;
-		clock-names = "aclk";
-		iommus = <&smmu 0>, <&smmu 1>, <&smmu 2>, <&smmu 3>,
-			<&smmu 4>, <&smmu 5>, <&smmu 6>, <&smmu 7>,
-			<&smmu 8>, <&smmu 9>;
-
-		dp0_pipe0: pipeline@0 {
-			clocks = <&fpgaosc2>;
-			clock-names = "pxclk";
-			reg = <0>;
-
-			port {
-				dp0_pipe0_out: endpoint {
-					remote-endpoint = <&db_dvi0_in>;
-				};
-			};
-		};
-
-		dp0_pipe1: pipeline@1 {
-			clocks = <&fpgaosc2>;
-			clock-names = "pxclk";
-			reg = <1>;
-
-			port {
-				dp0_pipe1_out: endpoint {
-					remote-endpoint = <&db_dvi1_in>;
-				};
-			};
-		};
-	};
-	...
-};

Documentation/devicetree/bindings/display/arm,komeda.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/arm,komeda.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Arm Komeda display processor
+
+maintainers:
+  - Liviu Dudau <Liviu.Dudau@arm.com>
+  - Andre Przywara <andre.przywara@arm.com>
+
+description:
+  The Arm Mali D71 display processor supports up to two displays with up
+  to a 4K resolution each. Each pipeline can be composed of up to four
+  layers. It is typically connected to a digital display connector like HDMI.
+
+properties:
+  compatible:
+    oneOf:
+      - items:
+          - const: arm,mali-d32
+          - const: arm,mali-d71
+      - const: arm,mali-d71
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clock-names:
+    const: aclk
+
+  clocks:
+    maxItems: 1
+    description: The main DPU processor clock
+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 0
+
+  memory-region:
+    maxItems: 1
+    description:
+      Phandle to a node describing memory to be used for the framebuffer.
+      If not present, the framebuffer may be located anywhere in memory.
+
+  iommus:
+    description:
+      The stream IDs for each of the used pipelines, each four IDs for the
+      four layers, plus one for the write-back stream.
+    minItems: 5
+    maxItems: 10
+
+patternProperties:
+  '^pipeline@[01]$':
+    type: object
+    description:
+      clocks
+
+    properties:
+      reg:
+        enum: [ 0, 1 ]
+
+      clock-names:
+        const: pxclk
+
+      clocks:
+        maxItems: 1
+        description: The input reference for the pixel clock.
+
+      port:
+        $ref: /schemas/graph.yaml#/$defs/port-base
+        unevaluatedProperties: false
+
+additionalProperties: false
+
+required:
+  - "#address-cells"
+  - "#size-cells"
+  - compatible
+  - reg
+  - interrupts
+  - clock-names
+  - clocks
+  - pipeline@0
+
+examples:
+  - |
+    display@c00000 {
+        #address-cells = <1>;
+        #size-cells = <0>;
+        compatible = "arm,mali-d71";
+        reg = <0xc00000 0x20000>;
+        interrupts = <168>;
+        clocks = <&dpu_aclk>;
+        clock-names = "aclk";
+        iommus = <&smmu 0>, <&smmu 1>, <&smmu 2>, <&smmu 3>,
+                 <&smmu 8>,
+                 <&smmu 4>, <&smmu 5>, <&smmu 6>, <&smmu 7>,
+                 <&smmu 9>;
+
+        dp0_pipe0: pipeline@0 {
+            clocks = <&fpgaosc2>;
+            clock-names = "pxclk";
+            reg = <0>;
+
+            port {
+                dp0_pipe0_out: endpoint {
+                    remote-endpoint = <&db_dvi0_in>;
+                };
+            };
+        };
+
+        dp0_pipe1: pipeline@1 {
+            clocks = <&fpgaosc2>;
+            clock-names = "pxclk";
+            reg = <1>;
+
+            port {
+                dp0_pipe1_out: endpoint {
+                    remote-endpoint = <&db_dvi1_in>;
+                };
+            };
+        };
+    };
+...