[RFC PATCH v1 09/10] dt-bindings: timer: Add ACLINT MSWI and SSWI bindings

[Anup Patel <anup.patel@wdc.com>]

We add DT bindings documentation for the ACLINT MSWI and SSWI
devices found on RISC-V SOCs.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
---
 .../riscv,aclint-swi.yaml                     | 82 +++++++++++++++++++
 1 file changed, 82 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/riscv,aclint-swi.yaml

diff --git a/Documentation/devicetree/bindings/interrupt-controller/riscv,aclint-swi.yaml b/Documentation/devicetree/bindings/interrupt-controller/riscv,aclint-swi.yaml
new file mode 100644
index 000000000000..bed15411c18f
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/riscv,aclint-swi.yaml
@@ -0,0 +1,82 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/interrupt-controller/riscv,aclint-swi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RISC-V ACLINT Software Interrupt Devices
+
+maintainers:
+  - Anup Patel <anup.patel@wdc.com>
+
+description:
+  RISC-V SOCs include an implementation of the M-level software interrupt
+  (MSWI) device and the S-level software interrupt (SSWI) device defined
+  in the RISC-V Advanced Core Local Interruptor (ACLINT) specification.
+
+  The ACLINT MSWI (and SSWI) devices are documented in the RISC-V ACLINT
+  specification located at
+  https://github.com/riscv/riscv-aclint/blob/main/riscv-aclint.adoc.
+
+  The ACLINT MSWI and SSWI devices directly connect to the M-level and
+  S-level software interrupt lines of various HARTs (or CPUs) respectively
+  so the RISC-V per-HART (or per-CPU) local interrupt controller is the
+  parent interrupt controller for the ACLINT MSWI and SSWI devices.
+
+allOf:
+  - $ref: /schemas/interrupt-controller.yaml#
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - riscv,aclint-mswi
+          - riscv,aclint-sswi
+
+    description:
+      Should be "<vendor>,<chip>-aclint-mswi" and "riscv,aclint-mswi" OR
+      "<vendor>,<chip>-aclint-sswi" and "riscv,aclint-sswi".
+
+  reg:
+    maxItems: 1
+
+  "#interrupt-cells":
+    const: 0
+
+  interrupts-extended:
+    minItems: 1
+
+  interrupt-controller: true
+
+additionalProperties: false
+
+required:
+  - compatible
+  - reg
+  - interrupts-extended
+  - interrupt-controller
+  - "#interrupt-cells"
+
+examples:
+  - |
+    // Example 1 (RISC-V MSWI device used by Linux RISC-V NoMMU kernel):
+
+    interrupt-controller@2000000 {
+      compatible = "riscv,aclint-mswi";
+      interrupts-extended = <&cpu1intc 3 &cpu2intc 3 &cpu3intc 3 &cpu4intc 3>;
+      reg = <0x2000000 0x4000>;
+      interrupt-controller;
+      #interrupt-cells = <0>;
+    };
+
+  - |
+    // Example 2 (RISC-V SSWI device used by Linux RISC-V MMU kernel):
+
+    interrupt-controller@2100000 {
+      compatible = "riscv,aclint-sswi";
+      interrupts-extended = <&cpu1intc 1 &cpu2intc 1 &cpu3intc 1 &cpu4intc 1>;
+      reg = <0x2100000 0x4000>;
+      interrupt-controller;
+      #interrupt-cells = <0>;
+    };
+...
-- 
2.25.1