Introduce the mailbox module for AST27XX series SoC, which is responsible
for interchanging messages between asymmetric processors.

Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com>
---
 .../mailbox/aspeed,ast2700-mailbox.yaml       | 61 +++++++++++++++++++
 1 file changed, 61 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mailbox/aspeed,ast2700-mailbox.yaml

diff --git a/Documentation/devicetree/bindings/mailbox/aspeed,ast2700-mailbox.yaml b/Documentation/devicetree/bindings/mailbox/aspeed,ast2700-mailbox.yaml
new file mode 100644
index 000000000000..27738c462e33
--- /dev/null
+++ b/Documentation/devicetree/bindings/mailbox/aspeed,ast2700-mailbox.yaml
@@ -0,0 +1,61 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mailbox/aspeed,ast2700-mailbox.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ASPEED AST2700 mailbox controller
+
+maintainers:
+  - Jammy Huang <jammy_huang@aspeedtech.com>
+
+description:
+  ASPEED AST2700 has multiple processors that need to communicate with each
+  other. The mailbox controller provides a way for these processors to send
+  messages to each other. It is a hardware-based inter-processor communication
+  mechanism that allows processors to send and receive messages through
+  dedicated channels.
+  The mailbox's tx/rx are independent, meaning that one processor can send a
+  message while another processor is receiving a message simultaneously.
+  There are 4 channels available for both tx and rx operations. Each channel
+  has a FIFO buffer that can hold messages of a fixed size (32 bytes in this
+  case).
+  The mailbox controller also supports interrupt generation, allowing
+  processors to notify each other when a message is available or when an event
+  occurs.
+
+properties:
+  compatible:
+    const: aspeed,ast2700-mailbox
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  "#mbox-cells":
+    const: 1
+    description: |
+      <&phandle channel>
+      phandle : Label name of mailbox controller
+      channel : 0-3, Channel index
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - "#mbox-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    mbox@12c1c200 {
+        compatible = "aspeed,ast2700-mailbox";
+        reg = <0x0 0x12c1c200 0x0 0x200>;
+        interrupts = <GIC_SPI 103 IRQ_TYPE_LEVEL_HIGH>;
+        #mbox-cells = <1>;
+    };
-- 
2.25.1

On Tue, 03 Jun 2025 15:54:49 +0800, Jammy Huang wrote:
> Introduce the mailbox module for AST27XX series SoC, which is responsible
> for interchanging messages between asymmetric processors.
> 
> Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com>
> ---
>  .../mailbox/aspeed,ast2700-mailbox.yaml       | 61 +++++++++++++++++++
>  1 file changed, 61 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mailbox/aspeed,ast2700-mailbox.yaml
> 

My bot found errors running 'make dt_binding_check' on your patch:

yamllint warnings/errors:

dtschema/dtc warnings/errors:
Error: Documentation/devicetree/bindings/mailbox/aspeed,ast2700-mailbox.example.dts:29.27-28 syntax error
FATAL ERROR: Unable to parse input tree
make[2]: *** [scripts/Makefile.dtbs:131: Documentation/devicetree/bindings/mailbox/aspeed,ast2700-mailbox.example.dtb] Error 1
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [/builds/robherring/dt-review-ci/linux/Makefile:1519: dt_binding_check] Error 2
make: *** [Makefile:248: __sub-make] Error 2

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20250603075450.133604-2-jammy_huang@aspeedtech.com

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

On 03/06/2025 09:54, Jammy Huang wrote:
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  "#mbox-cells":
> +    const: 1
> +    description: |
> +      <&phandle channel>
> +      phandle : Label name of mailbox controller
> +      channel : 0-3, Channel index

Drop description, pretty obvious (or just say that second argument is
channel number).

> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - "#mbox-cells"
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +
> +    mbox@12c1c200 {

mailbox@

With these fixed:

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>


Best regards,
Krzysztof

On 03/06/2025 11:22, Krzysztof Kozlowski wrote:
>> +required:
>> +  - compatible
>> +  - reg
>> +  - interrupts
>> +  - "#mbox-cells"
>> +
>> +additionalProperties: false
>> +
>> +examples:
>> +  - |
>> +    #include <dt-bindings/interrupt-controller/irq.h>
>> +
>> +    mbox@12c1c200 {
> 
> mailbox@
> 
> With these fixed:
> 
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Huh, not tested.... so obviously un-reviewed.

Test your code BEFORE you send, not via community services.

Best regards,
Krzysztof