Re: [PATCH v2] dt-bindings: interrupt-controller: Convert Atmel AIC to json-schema

[Dharma.B]

Hi Rob,

On 12/02/24 7:38 pm, Rob Herring wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> On Fri, Feb 09, 2024 at 03:31:22PM +0530, Dharma Balasubiramani wrote:
>> Convert the Atmel AIC binding document to DT schema format using
>> json-schema.
>>
>> Signed-off-by: Dharma Balasubiramani <dharma.b@xxxxxxxxxxxxx>
>> ---
>> Changelog
>> v1 -> v2
>> - Drop the '|' as there is no formatting to preserve.
>> - Remove unnecessary marketing statement from description.
>> - Drop the description for interrupts and reg, it's obvious.
>> - Put reg after compatible.
>> - Drop comment in example.
>> - Drop the example of device that is wired to an AIC as it's(dma) binding is
>>    not yet available.
>> ---
>>   .../interrupt-controller/atmel,aic.txt        | 43 -----------
>>   .../interrupt-controller/atmel,aic.yaml       | 74 +++++++++++++++++++
>>   2 files changed, 74 insertions(+), 43 deletions(-)
>>   delete mode 100644 Documentation/devicetree/bindings/interrupt-controller/atmel,aic.txt
>>   create mode 100644 Documentation/devicetree/bindings/interrupt-controller/atmel,aic.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/interrupt-controller/atmel,aic.txt b/Documentation/devicetree/bindings/interrupt-controller/atmel,aic.txt
>> deleted file mode 100644
>> index 7079d44bf3ba..000000000000
>> --- a/Documentation/devicetree/bindings/interrupt-controller/atmel,aic.txt
>> +++ /dev/null
>> @@ -1,43 +0,0 @@
>> -* Advanced Interrupt Controller (AIC)
>> -
>> -Required properties:
>> -- compatible: Should be:
>> -    - "atmel,<chip>-aic" where  <chip> can be "at91rm9200", "sama5d2",
>> -      "sama5d3" or "sama5d4"
>> -    - "microchip,<chip>-aic" where <chip> can be "sam9x60"
>> -
>> -- interrupt-controller: Identifies the node as an interrupt controller.
>> -- #interrupt-cells: The number of cells to define the interrupts. It should be 3.
>> -  The first cell is the IRQ number (aka "Peripheral IDentifier" on datasheet).
>> -  The second cell is used to specify flags:
>> -    bits[3:0] trigger type and level flags:
>> -      1 = low-to-high edge triggered.
>> -      2 = high-to-low edge triggered.
>> -      4 = active high level-sensitive.
>> -      8 = active low level-sensitive.
>> -      Valid combinations are 1, 2, 3, 4, 8.
>> -      Default flag for internal sources should be set to 4 (active high).
>> -  The third cell is used to specify the irq priority from 0 (lowest) to 7
>> -  (highest).
>> -- reg: Should contain AIC registers location and length
>> -- atmel,external-irqs: u32 array of external irqs.
>> -
>> -Examples:
>> -     /*
>> -      * AIC
>> -      */
>> -     aic: interrupt-controller@fffff000 {
>> -             compatible = "atmel,at91rm9200-aic";
>> -             interrupt-controller;
>> -             #interrupt-cells = <3>;
>> -             reg = <0xfffff000 0x200>;
>> -     };
>> -
>> -     /*
>> -      * An interrupt generating device that is wired to an AIC.
>> -      */
>> -     dma: dma-controller@ffffec00 {
>> -             compatible = "atmel,at91sam9g45-dma";
>> -             reg = <0xffffec00 0x200>;
>> -             interrupts = <21 4 5>;
>> -     };
>> diff --git a/Documentation/devicetree/bindings/interrupt-controller/atmel,aic.yaml b/Documentation/devicetree/bindings/interrupt-controller/atmel,aic.yaml
>> new file mode 100644
>> index 000000000000..df81115a8b7f
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/interrupt-controller/atmel,aic.yaml
>> @@ -0,0 +1,74 @@
>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/interrupt-controller/atmel,aic.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Advanced Interrupt Controller (AIC)
>> +
>> +maintainers:
>> +  - Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx>
>> +  - Dharma balasubiramani <dharma.b@xxxxxxxxxxxxx>
>> +
>> +description:
>> +  The Advanced Interrupt Controller (AIC) is an 8-level priority, individually
>> +  maskable, vectored interrupt controller providing handling of up to one
>> +  hundred and twenty-eight interrupt sources.
>> +
>> +allOf:
>> +  - $ref: /schemas/interrupt-controller.yaml#
>> +
>> +properties:
>> +  compatible:
>> +    enum:
>> +      - atmel,at91rm9200-aic
>> +      - atmel,sama5d2-aic
>> +      - atmel,sama5d3-aic
>> +      - atmel,sama5d4-aic
>> +      - microchip,sam9x60-aic
>> +
>> +  reg:
>> +    maxItems: 1
>> +
>> +  interrupt-controller: true
>> +
>> +  "#interrupt-cells":
>> +    const: 3
>> +    description: |
>> +      The 1st cell is the IRQ number (Peripheral IDentifier on datasheet).
>> +      The 2nd cell specifies flags:
>> +        bits[3:0] trigger type and level flags:
>> +          1 = low-to-high edge triggered.
>> +          2 = high-to-low edge triggered.
>> +          4 = active high level-sensitive.
>> +          8 = active low level-sensitive.
>> +        Valid combinations: 1, 2, 3, 4, 8.
>> +        Default for internal sources: 4 (active high).
>> +      The 3rd cell specifies irq priority from 0 (lowest) to 7 (highest).
>> +
>> +  interrupts:
>> +    maxItems: 1
>> +
>> +  atmel,external-irqs:
>> +    $ref: /schemas/types.yaml#/definitions/uint32-array
>> +    description: u32 array of external irqs.
> 
> Constraints on the array size and/or entry values?

The hardware's support for external IRQs may differ, which is why a u32 
array is utilized. This choice is based on the fact that IRQ numbers are 
commonly expressed as integers, and a 32-bit unsigned integer provides a 
standardized size capable of representing a broad range of numbers. This 
size is more than adequate for accommodating IRQ numbering.


> 
>> +
>> +required:
>> +  - compatible
>> +  - reg
>> +  - interrupt-controller
>> +  - "#interrupt-cells"
>> +  - atmel,external-irqs
>> +
>> +unevaluatedProperties: false
>> +
>> +examples:
>> +  - |
>> +    interrupt-controller@fffff000 {
>> +      compatible = "atmel,at91rm9200-aic";
>> +      interrupt-controller;
>> +      #interrupt-cells = <3>;
>> +      reg = <0xfffff000 0x200>;
>> +      atmel,external-irqs = <31>;
>> +    };
>> +...
>>
>> base-commit: 0dd3ee31125508cd67f7e7172247f05b7fd1753a
>> --
>> 2.25.1
>>

-- 
With Best Regards,
Dharma B.