Re: [PATCH v3 1/4] dt-bindings: mfd: aspeed: support for AST2700

[Krzysztof Kozlowski <krzk@kernel.org>]

On 19/09/2024 09:13, Ryan Chen wrote:
>> Subject: Re: [PATCH v3 1/4] dt-bindings: mfd: aspeed: support for AST2700
>>
>> On 19/09/2024 08:05, Ryan Chen wrote:
>>>>> diff --git
>>>>> a/Documentation/devicetree/bindings/mfd/aspeed,ast2x00-scu.yaml
>>>>> b/Documentation/devicetree/bindings/mfd/aspeed,ast2x00-scu.yaml
>>>>> index 86ee69c0f45b..127a357051cd 100644
>>>>> --- a/Documentation/devicetree/bindings/mfd/aspeed,ast2x00-scu.yaml
>>>>> +++ b/Documentation/devicetree/bindings/mfd/aspeed,ast2x00-scu.yaml
>>>>> @@ -9,6 +9,8 @@ title: Aspeed System Control Unit
>>>>>  description:
>>>>>    The Aspeed System Control Unit manages the global behaviour of
>>>>> the
>>>> SoC,
>>>>>    configuring elements such as clocks, pinmux, and reset.
>>>>> +  In AST2700 SOC which has two soc connection, each soc have its
>>>>> + own scu  register control, ast2700-scu0 for soc0, ast2700-scu1 for
>> soc1.
>>>>>
>>>>>  maintainers:
>>>>>    - Joel Stanley <joel@jms.id.au>
>>>>> @@ -21,6 +23,8 @@ properties:
>>>>>            - aspeed,ast2400-scu
>>>>>            - aspeed,ast2500-scu
>>>>>            - aspeed,ast2600-scu
>>>>> +          - aspeed,ast2700-scu0
>>>>> +          - aspeed,ast2700-scu1
>>>>>        - const: syscon
>>>>>        - const: simple-mfd
>>>>>
>>>>> @@ -30,10 +34,12 @@ properties:
>>>>>    ranges: true
>>>>>
>>>>>    '#address-cells':
>>>>> -    const: 1
>>>>> +    minimum: 1
>>>>> +    maximum: 2
>>>>>
>>>>>    '#size-cells':
>>>>> -    const: 1
>>>>> +    minimum: 1
>>>>> +    maximum: 2
>>>>
>>>> Why do the children have 64 bit addressing?
>>>
>>> AST2700 is 64bit address, so it also.
>>
>> But why do they need it?
>>
> Sorry, I may not understand your point.

I asked why do you think children require 64-bit addressing, instead of
working with existing 32-bit address.

> Since address-cell = <2>, Do you mean size-cell still 1?

No... although that's another point, how bug address size is there? For
the children?

> If yes. I do the dts check it need size-cells=<2>, when I do address-cells = <2>

Well, I talk about bus and children addressing. It's kind of obvious
that changing one property means using different reg...

Best regards,
Krzysztof