[PATCH v2 2/3] dt-bindings: mailbox: add binding for Microchip IPC mailbox controller

[Valentina Fernandez]

Add a dt-binding for the Microchip Inter-Processor Communication (IPC)
mailbox controller.

Signed-off-by: Valentina Fernandez <valentina.fernandezalanis at microchip.com>
---
 .../bindings/mailbox/microchip,sbi-ipc.yaml   | 108 ++++++++++++++++++
 1 file changed, 108 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mailbox/microchip,sbi-ipc.yaml

diff --git a/Documentation/devicetree/bindings/mailbox/microchip,sbi-ipc.yaml b/Documentation/devicetree/bindings/mailbox/microchip,sbi-ipc.yaml
new file mode 100644
index 000000000000..90a7932118b5
--- /dev/null
+++ b/Documentation/devicetree/bindings/mailbox/microchip,sbi-ipc.yaml
@@ -0,0 +1,108 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mailbox/microchip,sbi-ipc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Microchip Inter-processor communication (IPC) mailbox controller
+
+maintainers:
+  - Valentina Fernandez <valentina.fernandezalanis at microchip.com>
+
+description:
+  The Microchip Inter-processor Communication (IPC) facilitates
+  message passing between processors using an interrupt signaling
+  mechanism.
+  This SBI interface is compatible with the Mi-V Inter-hart
+  Communication (IHC) IP.
+  The microchip,sbi-ipc compatible string is inteded for use by software
+  running in supervisor privileged mode (s-mode). The SoC-specific
+  compatibles are inteded for use by the SBI implementation in machine
+  mode (m-mode).
+
+properties:
+  compatible:
+    enum:
+      - microchip,sbi-ipc
+      - microchip,miv-ihc-rtl-v2
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    minItems: 1
+    maxItems: 5
+
+  interrupt-names:
+    minItems: 1
+    maxItems: 5
+    items:
+      pattern: "^hart-[0-5]+$"
+
+  "#mbox-cells":
+    description:
+      For the SBI "device", the cell represents the global "logical" channel IDs.
+      The meaning of channel IDs are platform firmware dependent. The
+      SoC-specific compatibles are intended for use by the SBI implementation,
+      rather than s-mode software. There the cell would represent the physical
+      channel and do not vary depending on platform firmware.
+    const: 1
+
+  microchip,ihc-chan-disabled-mask:
+    description:
+      Represents the enable/disable state of the bi-directional IHC channels
+      within the MIV-IHC IP configuration. The mask is a 16-bit value, but only
+      the first 15 bits are utilized.Each of the bits corresponds to
+      one of the 15 IHC channels.
+      A bit set to '1' indicates that the corresponding channel is disabled,
+      and any read or write operations to that channel will return zero.
+      A bit set to '0' indicates that the corresponding channel is enabled
+      and will be accessible through its dedicated address range registers.
+      The remaining bit of the 16-bit mask is reserved and should be ignored.
+      The actual enable/disable state of each channel is determined by the
+      IP block’s configuration.
+    $ref: /schemas/types.yaml#/definitions/uint16
+    default: 0
+
+required:
+  - compatible
+  - interrupts
+  - interrupt-names
+  - "#mbox-cells"
+
+additionalProperties: false
+
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: microchip,sbi-ipc
+    then:
+      properties:
+        reg: false
+        microchip,ihc-chan-disabled-mask: false
+    else:
+      required:
+        - reg
+        - microchip,ihc-chan-disabled-mask
+
+examples:
+  - |
+    mailbox {
+      compatible = "microchip,sbi-ipc";
+      interrupt-parent = <&plic>;
+      interrupts = <180>, <179>, <178>;
+      interrupt-names = "hart-1", "hart-2", "hart-3";
+      #mbox-cells = <1>;
+    };
+  - |
+    mailbox at 50000000 {
+      compatible = "microchip,miv-ihc-rtl-v2";
+      microchip,ihc-chan-disabled-mask=  /bits/ 16 <0>;
+      reg = <0x50000000 0x1C000>;
+      interrupt-parent = <&plic>;
+      interrupts = <180>, <179>, <178>;
+      interrupt-names = "hart-1", "hart-2", "hart-3";
+      #mbox-cells = <1>;
+    };
-- 
2.34.1