[PATCH v6 05/10] dt-bindings: mailbox: add cix,sky1-mbox

Peter Chen
2025-04-15T07:27:30Z

From: Guomin Chen <Guomin.Chen@cixtech.com>

Add a dt-binding for the Cixtech Mailbox Controller.

Reviewed-by: Peter Chen <peter.chen@cixtech.com>
Signed-off-by: Lihua Liu <Lihua.Liu@cixtech.com>
Signed-off-by: Guomin Chen <Guomin.Chen@cixtech.com>
---
Changes for v3:
- Replace the direction attribute of the mailbox with the strings "rx" and "tx"

.../bindings/mailbox/cix,sky1-mbox.yaml | 71 +++++++++++++++++++
1 file changed, 71 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mailbox/cix,sky1-mbox.yaml

diff --git a/Documentation/devicetree/bindings/mailbox/cix,sky1-mbox.yaml b/Documentation/devicetree/bindings/mailbox/cix,sky1-mbox.yaml
new file mode 100644
index 000000000000..216186f7cc4d
--- /dev/null
+++ b/Documentation/devicetree/bindings/mailbox/cix,sky1-mbox.yaml
@@ -0,0 +1,71 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mailbox/cix,sky1-mbox.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Cixtech mailbox controller
+
+maintainers:
+ - Guomin Chen <Guomin.Chen@cixtech.com>
+
+description:
+ The Cixtech mailbox controller, used in the Cixtech Sky1 SoC,
+ is used for message transmission between multiple processors
+ within the SoC, such as the AP, PM, audio DSP, SensorHub MCU,
+ and others
+
+ Each Cixtech mailbox controller is unidirectional, so they are
+ typically used in pairs-one for receiving and one for transmitting.
+
+ Each Cixtech mailbox supports 11 channels with different transmission modes
+ channel 0-7 - Fast channel with 32bit transmit register and IRQ support
+ channel 8 - Doorbell mode,using the mailbox as an interrupt-generating
+ mechanism.
+ channel 9 - Fifo based channel with 32*32bit depth fifo and IRQ support
+ channel 10 - Reg based channel with 32*32bit transmit register and
+ Doorbell+transmit acknowledgment IRQ support
+
+properties:
+ compatible:
+ const: cix,sky1-mbox
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ "#mbox-cells":
+ const: 1
+
+ cix,mbox-dir:
+ $ref: /schemas/types.yaml#/definitions/string
+ description: Direction of the mailbox relative to the AP
+ enum: [tx, rx]
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - "#mbox-cells"
+ - cix,mbox-dir
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+ soc {
+ #address-cells = <2>;
+ #size-cells = <2>;
+
+ mbox_ap2pm: mailbox@30000000 {
+ compatible = "cix,sky1-mbox";
+ reg = <0 0x30000000 0 0x10000>;
+ interrupts = <GIC_SPI 136 IRQ_TYPE_LEVEL_HIGH 0>;
+ #mbox-cells = <1>;
+ cix,mbox-dir = "tx";
+ };
+ };
--
2.25.1