dt-bindings: riscv: convert plic bindings to json-schema

Convert device tree bindings for SiFive's PLIC to YAML format
Signed-off-by: Sagar Kadam <sagar.kadam@sifive.com>
Link: https://lore.kernel.org/r/1601393531-2402-3-git-send-email-sagar.kadam@sifive.comSigned-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/interrupt-controller/sifive,plic-1.0.0.txt

-SiFive Platform-Level Interrupt Controller (PLIC)
--------------------------------------------------
-
-SiFive SOCs include an implementation of the Platform-Level Interrupt Controller
-(PLIC) high-level specification in the RISC-V Privileged Architecture
-specification.  The PLIC connects all external interrupts in the system to all
-hart contexts in the system, via the external interrupt source in each hart.
-
-A hart context is a privilege mode in a hardware execution thread.  For example,
-in an 4 core system with 2-way SMT, you have 8 harts and probably at least two
-privilege modes per hart; machine mode and supervisor mode.
-
-Each interrupt can be enabled on per-context basis.  Any context can claim
-a pending enabled interrupt and then release it once it has been handled.
-
-Each interrupt has a configurable priority.  Higher priority interrupts are
-serviced first.  Each context can specify a priority threshold. Interrupts
-with priority below this threshold will not cause the PLIC to raise its
-interrupt line leading to the context.
-
-While the PLIC supports both edge-triggered and level-triggered interrupts,
-interrupt handlers are oblivious to this distinction and therefore it is not
-specified in the PLIC device-tree binding.
-
-While the RISC-V ISA doesn't specify a memory layout for the PLIC, the
-"sifive,plic-1.0.0" device is a concrete implementation of the PLIC that
-contains a specific memory layout, which is documented in chapter 8 of the
-SiFive U5 Coreplex Series Manual <https://static.dev.sifive.com/U54-MC-RVCoreIP.pdf>.
-
-Required properties:
-- compatible : "sifive,plic-1.0.0" and a string identifying the actual
-  detailed implementation in case that specific bugs need to be worked around.
-- #address-cells : should be <0> or more.
-- #interrupt-cells : should be <1> or more.
-- interrupt-controller : Identifies the node as an interrupt controller.
-- reg : Should contain 1 register range (address and length).
-- interrupts-extended : Specifies which contexts are connected to the PLIC,
-  with "-1" specifying that a context is not present.  Each node pointed
-  to should be a riscv,cpu-intc node, which has a riscv node as parent.
-- riscv,ndev: Specifies how many external interrupts are supported by
-  this controller.
-
-Example:
-
-	plic: interrupt-controller@c000000 {
-		#address-cells = <0>;
-		#interrupt-cells = <1>;
-		compatible = "sifive,plic-1.0.0", "sifive,fu540-c000-plic";
-		interrupt-controller;
-		interrupts-extended = <
-			&cpu0-intc 11
-			&cpu1-intc 11 &cpu1-intc 9
-			&cpu2-intc 11 &cpu2-intc 9
-			&cpu3-intc 11 &cpu3-intc 9
-			&cpu4-intc 11 &cpu4-intc 9>;
-		reg = <0xc000000 0x4000000>;
-		riscv,ndev = <10>;
-	};

Documentation/devicetree/bindings/interrupt-controller/sifive,plic-1.0.0.yaml

+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+# Copyright (C) 2020 SiFive, Inc.
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/interrupt-controller/sifive,plic-1.0.0.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SiFive Platform-Level Interrupt Controller (PLIC)
+
+description:
+  SiFive SOCs include an implementation of the Platform-Level Interrupt Controller
+  (PLIC) high-level specification in the RISC-V Privileged Architecture
+  specification. The PLIC connects all external interrupts in the system to all
+  hart contexts in the system, via the external interrupt source in each hart.
+
+  A hart context is a privilege mode in a hardware execution thread. For example,
+  in an 4 core system with 2-way SMT, you have 8 harts and probably at least two
+  privilege modes per hart; machine mode and supervisor mode.
+
+  Each interrupt can be enabled on per-context basis. Any context can claim
+  a pending enabled interrupt and then release it once it has been handled.
+
+  Each interrupt has a configurable priority. Higher priority interrupts are
+  serviced first.  Each context can specify a priority threshold. Interrupts
+  with priority below this threshold will not cause the PLIC to raise its
+  interrupt line leading to the context.
+
+  While the PLIC supports both edge-triggered and level-triggered interrupts,
+  interrupt handlers are oblivious to this distinction and therefore it is not
+  specified in the PLIC device-tree binding.
+
+  While the RISC-V ISA doesn't specify a memory layout for the PLIC, the
+  "sifive,plic-1.0.0" device is a concrete implementation of the PLIC that
+  contains a specific memory layout, which is documented in chapter 8 of the
+  SiFive U5 Coreplex Series Manual <https://static.dev.sifive.com/U54-MC-RVCoreIP.pdf>.
+
+maintainers:
+  - Sagar Kadam <sagar.kadam@sifive.com>
+  - Paul Walmsley  <paul.walmsley@sifive.com>
+  - Palmer Dabbelt <palmer@dabbelt.com>
+
+properties:
+  compatible:
+    items:
+      - const: sifive,fu540-c000-plic
+      - const: sifive,plic-1.0.0
+
+  reg:
+    maxItems: 1
+
+  '#address-cells':
+    const: 0
+
+  '#interrupt-cells':
+    const: 1
+
+  interrupt-controller: true
+
+  interrupts-extended:
+    minItems: 1
+    description:
+      Specifies which contexts are connected to the PLIC, with "-1" specifying
+      that a context is not present. Each node pointed to should be a
+      riscv,cpu-intc node, which has a riscv node as parent.
+
+  riscv,ndev:
+    $ref: "/schemas/types.yaml#/definitions/uint32"
+    description:
+      Specifies how many external interrupts are supported by this controller.
+
+required:
+  - compatible
+  - '#address-cells'
+  - '#interrupt-cells'
+  - interrupt-controller
+  - reg
+  - interrupts-extended
+  - riscv,ndev
+
+additionalProperties: false
+
+examples:
+  - |
+    plic: interrupt-controller@c000000 {
+      #address-cells = <0>;
+      #interrupt-cells = <1>;
+      compatible = "sifive,fu540-c000-plic", "sifive,plic-1.0.0";
+      interrupt-controller;
+      interrupts-extended = <
+        &cpu0_intc 11
+        &cpu1_intc 11 &cpu1_intc 9
+        &cpu2_intc 11 &cpu2_intc 9
+        &cpu3_intc 11 &cpu3_intc 9
+        &cpu4_intc 11 &cpu4_intc 9>;
+      reg = <0xc000000 0x4000000>;
+      riscv,ndev = <10>;
+    };