Re: [PATCH v2] dt-bindings: interrupt-controller: loongson,liointc: Fix warnings about liointc-2.0

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 21/08/2023 08:13, Binbin Zhou wrote:
> Since commit f4dee5d8e1fa ("dt-bindings: interrupt-controller: Add
> Loongson-2K1000 LIOINTC"), the loongson liointc supports configuring
> routes for 64-bit interrupt sources.
> 
> For liointc-2.0, we need to define two liointc nodes in dts, one for
> "0-31" interrupt sources and the other for "32-63" interrupt sources.
> This applies to mips Loongson-2K1000.
> 
> Unfortunately, there are some warnings about "loongson,liointc-2.0":
> 1. "interrupt-names" should be "required", the driver gets the parent
> interrupts through it.

No, why? Parent? This does not make sense.

> 
> 2. Since not all CPUs are multicore, e.g. Loongson-2K0500 is a
> single-core CPU, there is no core1-related registers. So "reg" and
> "reg-names" should be set to "minItems 2".
> 
> 3. Routing interrupts from "int0" is a common solution in practice, but
> theoretically there is no such requirement, as long as conflicts are
> avoided. So "interrupt-names" should be defined by "pattern".

Why? What the pattern has to do with anything in routing or not routing
something?

> 
> This fixes dtbs_check warning:
> 
> DTC_CHK arch/mips/boot/dts/loongson/loongson64_2core_2k1000.dtb
> arch/mips/boot/dts/loongson/loongson64_2core_2k1000.dtb: interrupt-controller@1fe11440: interrupt-names:0: 'int0' was expected
>       From schema: Documentation/devicetree/bindings/interrupt-controller/loongson,liointc.yaml
> arch/mips/boot/dts/loongson/loongson64_2core_2k1000.dtb: interrupt-controller@1fe11440: Unevaluated properties are not allowed ('interrupt-names' was unexpected)
>       From schema: Documentation/devicetree/bindings/interrupt-controller/loongson,liointc.yaml
> 
> Fixes: f4dee5d8e1fa ("dt-bindings: interrupt-controller: Add Loongson-2K1000 LIOINTC")
> Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn>
> ---
> V2:
> 1. Update commit message;
> 2. "interruprt-names" should be "required", the driver gets the parent
> interrupts through it;
> 3. Add more descriptions to explain the rationale for multiple nodes;
> 4. Rewrite if-else statements.
> 
> Link to V1:
> https://lore.kernel.org/all/20230815084713.1627520-1-zhoubinbin@loongson.cn/
> 
>  .../loongson,liointc.yaml                     | 74 +++++++++----------
>  1 file changed, 37 insertions(+), 37 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/interrupt-controller/loongson,liointc.yaml b/Documentation/devicetree/bindings/interrupt-controller/loongson,liointc.yaml
> index 00b570c82903..f695d3a75ddf 100644
> --- a/Documentation/devicetree/bindings/interrupt-controller/loongson,liointc.yaml
> +++ b/Documentation/devicetree/bindings/interrupt-controller/loongson,liointc.yaml
> @@ -11,11 +11,11 @@ maintainers:
>  
>  description: |
>    This interrupt controller is found in the Loongson-3 family of chips and
> -  Loongson-2K1000 chip, as the primary package interrupt controller which
> +  Loongson-2K series chips, as the primary package interrupt controller which
>    can route local I/O interrupt to interrupt lines of cores.
> -
> -allOf:
> -  - $ref: /schemas/interrupt-controller.yaml#
> +  In particular, the Loongson-2K1000/2K0500 has 64 interrupt sources that we
> +  need to describe with two dts nodes. One for interrupt sources "0-31" and
> +  the other for interrupt sources "32-63".
>  
>  properties:
>    compatible:
> @@ -24,15 +24,9 @@ properties:
>        - loongson,liointc-1.0a
>        - loongson,liointc-2.0
>  
> -  reg:
> -    minItems: 1
> -    maxItems: 3
> +  reg: true

No. Constraints must be here.

>  
> -  reg-names:
> -    items:
> -      - const: main
> -      - const: isr0
> -      - const: isr1
> +  reg-names: true

No, keep at least min/maxItems here.

>  
>    interrupt-controller: true
>  
> @@ -45,11 +39,9 @@ properties:
>    interrupt-names:
>      description: List of names for the parent interrupts.
>      items:
> -      - const: int0
> -      - const: int1
> -      - const: int2
> -      - const: int3
> +      pattern: int[0-3]
>      minItems: 1
> +    maxItems: 4

I don't see reason behind it.

>  
>    '#interrupt-cells':
>      const: 2
> @@ -69,32 +61,41 @@ required:
>    - compatible
>    - reg
>    - interrupts
> +  - interrupt-names

Why? You are doing multiple things at once, without proper explanation.

>    - interrupt-controller
>    - '#interrupt-cells'
>    - loongson,parent_int_map
>  
> -
>  unevaluatedProperties: false
>  
> -if:
> -  properties:
> -    compatible:
> -      contains:
> -        enum:
> -          - loongson,liointc-2.0
> -
> -then:
> -  properties:
> -    reg:
> -      minItems: 3
> -
> -  required:
> -    - reg-names
> -
> -else:
> -  properties:
> -    reg:
> -      maxItems: 1
> +allOf:
> +  - $ref: /schemas/interrupt-controller.yaml#
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - loongson,liointc-2.0
> +    then:
> +      properties:
> +        reg:
> +          minItems: 2
> +          items:
> +            - description: Interrupt routing registers.
> +            - description: Low/high 32-bit interrupt status routed to core0.
> +            - description: Low/high 32-bit interrupt status routed to core1.
> +        reg-names:
> +          minItems: 2
> +          items:
> +            - const: main
> +            - const: isr0
> +            - const: isr1

Srsly, why this is moved here from the top? It does not make sense.

> +      required:
> +        - reg-names
> +    else:
> +      properties:
> +        reg:
> +          maxItems: 1

so reg-names can be "pink-pony"?

Best regards,
Krzysztof