Re: [PATCH v2] dt-bindings: mailbox: add Versal IPI bindings

[Krzysztof Kozlowski]

On 13/12/2023 00:03, Tanmay Shah wrote:
> Add documentation for AMD-Xilinx Versal platform Inter Processor Interrupt
> controller. Versal IPI controller contains buffer-less IPI which do not
> have buffers for message passing. For such IPI channels message buffers
> are not expected and only notification to/from remote agent is expected.
> 
> Signed-off-by: Tanmay Shah <tanmay.shah@xxxxxxx>
> ---
> 


>  properties:
>    compatible:
> -    const: xlnx,zynqmp-ipi-mailbox
> +    enum:
> +      - xlnx,zynqmp-ipi-mailbox
> +      - xlnx,versal-ipi-mailbox
>  
>    method:
>      description: |
>        The method of calling the PM-API firmware layer.
> -      Permitted values are.
> -      - "smc" : SMC #0, following the SMCCC
> -      - "hvc" : HVC #0, following the SMCCC
> -

Independent change. Please do not mix logical changes in one patch.

>      $ref: /schemas/types.yaml#/definitions/string
>      enum:
>        - smc
> @@ -58,16 +56,26 @@ properties:
>    '#size-cells':
>      const: 2
>  
> -  xlnx,ipi-id:
> -    description: |
> -      Remote Xilinx IPI agent ID of which the mailbox is connected to.
> -    $ref: /schemas/types.yaml#/definitions/uint32
> +  reg:
> +    minItems: 1
> +    maxItems: 2
> +
> +  reg-names:
> +    minItems: 1
> +    maxItems: 2

I don't understand why this change is here. Previously you did not have
MMIO address space? If yes, then where do you restrict the old device to
disallow these?


>  
>    interrupts:
>      maxItems: 1
>  
>    ranges: true
>  
> +  xlnx,ipi-id:
> +    description: |
> +      Remote Xilinx IPI agent ID of which the mailbox is connected to.
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    minimum: 0
> +    maximum: 64
> +
>  patternProperties:
>    '^mailbox@[0-9a-f]+$':
>      description: Internal ipi mailbox node
> @@ -76,57 +84,116 @@ patternProperties:
>      properties:
>  
>        compatible:
> -        const: xlnx,zynqmp-ipi-dest-mailbox
> +        enum:
> +          - xlnx,zynqmp-ipi-dest-mailbox
> +          - xlnx,versal-ipi-dest-mailbox
>  
> -      xlnx,ipi-id:
> -        description:
> -          Remote Xilinx IPI agent ID of which the mailbox is connected to.
> -        $ref: /schemas/types.yaml#/definitions/uint32
> +      reg:
> +        minItems: 1
> +        maxItems: 4
> +
> +      reg-names:
> +        minItems: 1
> +        maxItems: 4

Same concern.

>  
>        '#mbox-cells':
>          const: 1
>          description:
>            It contains tx(0) or rx(1) channel IPI id number.
>  
> -      reg:
> -        maxItems: 4
> -
> -      reg-names:
> -        items:
> -          - const: local_request_region
> -          - const: local_response_region
> -          - const: remote_request_region
> -          - const: remote_response_region
> +      xlnx,ipi-id:
> +        description:
> +          Remote Xilinx IPI agent ID of which the mailbox is connected to.
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        minimum: 0
> +        maximum: 64
>  
>      required:
>        - compatible
>        - reg
>        - reg-names
>        - "#mbox-cells"
> -
> -additionalProperties: false
> -
> +      - xlnx,ipi-id
> +
> +    allOf:
> +      - if:
> +          properties:
> +            compatible:
> +              contains:
> +                enum:
> +                  - xlnx,zynqmp-ipi-dest-mailbox
> +        then:
> +          properties:
> +            reg:
> +              items:
> +                - description: Host agent request message buffer
> +                - description: Host agent response message buffer
> +                - description: Remote agent request message buffer
> +                - description: Remote agent response message buffer
> +
> +            reg-names:
> +              items:
> +                - const: local_request_region
> +                - const: local_response_region
> +                - const: remote_request_region
> +                - const: remote_response_region
> +        else:
> +          properties:
> +            reg:
> +              minItems: 1
> +              items:
> +                - description: Remote IPI agent control register
> +                - description: Remote IPI agent optional message buffer

Were these described in old binding? If not, it's a separate change.

> +
> +            reg-names:
> +              minItems: 1
> +              items:
> +                - const: ctrl
> +                - const: msg

Blank line

>  required:
>    - compatible
> -  - interrupts
>    - '#address-cells'
>    - '#size-cells'
> +  - interrupts

Separate change with its own rationale. Trivial cleanups can be
organized in one patch, but should not be mixed with adding new devices.

>    - xlnx,ipi-id
>  
> +allOf:
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - xlnx,versal-ipi-mailbox
> +    then:
> +      properties:
> +        reg:
> +          items:
> +            - description: Host IPI agent control registers
> +            - description: Host IPI agent optional message buffers
> +
> +        reg-names:
> +          items:
> +            - const: ctrl
> +            - const: msg
> +
> +      required:
> +        - reg
> +        - reg-names
> +
> +additionalProperties: false
> +
> +

Just one blank line.

>  examples:
>    - |
>      #include<dt-bindings/interrupt-controller/arm-gic.h>
>  
> -    amba {
> -      #address-cells = <0x2>;
> -      #size-cells = <0x2>;
> +    bus {
>        zynqmp-mailbox {
>          compatible = "xlnx,zynqmp-ipi-mailbox";
>          interrupts = <GIC_SPI 29 IRQ_TYPE_LEVEL_HIGH>;
>          xlnx,ipi-id = <0>;
>          #address-cells = <2>;
>          #size-cells = <2>;
> -        ranges;

How is this related to Versal?

>  
>          mailbox: mailbox@ff9905c0 {
>            compatible = "xlnx,zynqmp-ipi-dest-mailbox";
> @@ -144,4 +211,41 @@ examples:
>        };
>      };
>  
> +  - |
> +    #include<dt-bindings/interrupt-controller/arm-gic.h>
> +
> +    bus {
> +      #address-cells = <2>;
> +      #size-cells = <2>;
> +      zynqmp-mailbox@ff300000 {

mailbox@

> +        compatible = "xlnx,versal-ipi-mailbox";
> +        interrupts = <GIC_SPI 29 IRQ_TYPE_LEVEL_HIGH>;
> +        #address-cells = <2>;
> +        #size-cells = <2>;
> +        reg = <0x0 0xff300000 0x0 0x1000>,
> +              <0x0 0xff990000 0x0 0x1ff>;
> +        reg-names = "ctrl", "msg";
> +        xlnx,ipi-id = <0>;
> +        ranges;
> +


Best regards,
Krzysztof