[RFC PATCH v2 04/31] Documentation: Add binding for kalray,kv3-1-apic-mailbox

[Yann Sionneau]

From: Jules Maselbas <jmaselbas at kalray.eu>

Add documentation for `kalray,kv3-1-core-intc` binding.

Co-developed-by: Jules Maselbas <jmaselbas at kalray.eu>
Signed-off-by: Jules Maselbas <jmaselbas at kalray.eu>
Signed-off-by: Yann Sionneau <ysionneau at kalray.eu>
---

Notes:
    V1 -> V2: new patch

 .../kalray,kv3-1-apic-mailbox.yaml            | 75 +++++++++++++++++++
 1 file changed, 75 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/kalray,kv3-1-apic-mailbox.yaml

diff --git a/Documentation/devicetree/bindings/interrupt-controller/kalray,kv3-1-apic-mailbox.yaml b/Documentation/devicetree/bindings/interrupt-controller/kalray,kv3-1-apic-mailbox.yaml
new file mode 100644
index 000000000000..e1eb1c9fda0d
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/kalray,kv3-1-apic-mailbox.yaml
@@ -0,0 +1,75 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/interrupt-controller/kalray,kv3-1-apic-mailbox#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Kalray kv3-1 APIC-Mailbox
+
+description: |
+  Each cluster in the Coolidge SoC includes an Advanced Programmable Interrupt
+  Controller (APIC) which is split in two part:
+    - a Generic Interrupt Controller (referred as APIC-GIC)
+    - a Mailbox Controller           (referred as APIC-Mailbox)
+  The APIC-Mailbox contains 128 mailboxes of 8 bytes (size of a word),
+  this hardware block is basically a 1 KB of smart memory space.
+  Each mailbox can be independently configured with a trigger condition
+  and an input mode function.
+
+  Input mode are:
+   - write
+   - bitwise OR
+   - add
+
+  Interrupts are generated on a write when the mailbox content value
+  match the configured trigger condition.
+  Available conditions are:
+   - doorbell: always raise interruption on write
+   - match: when the mailbox's value equal the configured trigger value
+   - barrier: same as match but the mailbox's value is cleared on trigger
+   - threshold: when the mailbox's value is greater than, or equal to, the
+     configured trigger value
+
+  Since this hardware block generates IRQs based on writes to some memory
+  locations, it is both an interrupt controller and an MSI controller.
+
+allOf:
+  - $ref: /schemas/interrupt-controller.yaml#
+
+properties:
+  compatible:
+    const: kalray,kv3-1-apic-mailbox
+  "#interrupt-cells":
+    const: 1
+    description:
+      The IRQ number.
+  interrupt-controller: true
+  interrupt-parent: true
+  interrupts:
+    maxItems: 128
+    description: |
+     Specifies the interrupt line(s) in the interrupt-parent controller node;
+     valid values depend on the type of parent interrupt controller
+  msi-controller: true
+
+required:
+  - compatible
+  - reg
+  - "#interrupt-cells"
+  - interrupt-controller
+  - interrupt-parent
+  - interrupts
+  - msi-controller
+
+examples:
+  - |
+    apic_mailbox: interrupt-controller at a00000 {
+        compatible = "kalray,kv3-1-apic-gic";
+        reg = <0 0xa00000 0 0x0f200>;
+        #interrupt-cells = <1>;
+        interrupt-controller;
+        interrupt-parent = <&apic_gic>;
+        interrups = <0 1 2 3 4 5 6 7 8 9>;
+    };
+
+...
-- 
2.37.2