Re: [PATCH 1/3] dt-bindings: PHY: P2U: Add PCIe lane margining support

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

On 30/11/2022 16:11, Manikanta Maddireddy wrote:
> Thank you for quick review. I will wait for other reviewers to review 
> patch 2 & 3.
> I will address all review comments and sendnew revision.
> 
> On 11/24/2022 2:15 PM, Krzysztof Kozlowski wrote:
>> External email: Use caution opening links or attachments
>>
>>
>> On 24/11/2022 09:35, Manikanta Maddireddy wrote:
>>> Tegra234 supports PCIe lane margining. P2U HW acts as a relay to exchange
>> typo: merging?
> It is not typo, it is PCIe feature lane margining.
> https://pcisig.com/pushing-limits-understanding-lane-margining-pcie%C2%AE
>>
>>> margin control data and margin status between PCIe controller and UPHY.
>> Please use scripts/get_maintainers.pl to get a list of necessary people
>> and lists to CC.  It might happen, that command when run on an older
>> kernel, gives you outdated entries.  Therefore please be sure you base
>> your patches on recent Linux kernel.
> I verified these patches on 6.0.0-rc6 kernel and executed get_maintainers.pl
> script on it. Did I miss anyone here?

Yes. At least Rob, maybe more. You need to CC all
maintainers/reviewers/supporters and all mailing lists.

It's not my task to verify each of these addresses to check whether you
really missed someone or not. I spotted at least one missing address so
just run get_maintainers.pl and use all entries from there.


>>
>>
>>> Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
>>> ---
>>>   .../bindings/phy/phy-tegra194-p2u.yaml        | 50 +++++++++++++++++++
>>>   1 file changed, 50 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/phy/phy-tegra194-p2u.yaml b/Documentation/devicetree/bindings/phy/phy-tegra194-p2u.yaml
>>> index 4dc5205d893b..0ba3f6a0b474 100644
>>> --- a/Documentation/devicetree/bindings/phy/phy-tegra194-p2u.yaml
>>> +++ b/Documentation/devicetree/bindings/phy/phy-tegra194-p2u.yaml
>>> @@ -40,6 +40,51 @@ properties:
>>>     '#phy-cells':
>>>       const: 0
>>>
>>> +  interrupts:
>>> +    items:
>>> +      description: P2U interrupt for Gen4 lane margining functionality.
>> typo: merging?
> It is not typo, it is PCIe feature lane margining.
> https://pcisig.com/pushing-limits-understanding-lane-margining-pcie%C2%AE
>>
>>> +
>>> +  interrupt-names:
>>> +    items:
>>> +      - const: intr
>> Drop entire property, not really useful.
> In driver, I am using platform_get_irq_byname(), I will change it to 
> platform_get_irq()
> and drop this property.
>>
>>> +
>>> +  nvidia,bpmp:
>>> +    $ref: /schemas/types.yaml#/definitions/phandle-array
>>> +    description: Must contain a pair of phandles to BPMP controller node followed by P2U ID.
>>> +    items:
>>> +      - items:
>>> +          - description: phandle to BPMP controller node
>>> +          - description: P2U instance ID
>>> +            maximum: 24
>>> +
>>> +allOf:
>>> +  - if:
>>> +      properties:
>>> +        compatible:
>>> +          contains:
>>> +            enum:
>>> +              - nvidia,tegra194-p2u
>>> +    then:
>>> +      required:
>>> +        - reg
>>> +        - reg-names
>>> +        - '#phy-cells'
>> That's not how it should be done. You have only two variants here, so
>> add a "required:" block with above and only one if:then: clause for
>> interrupts and nvidia,bpmp.
>>
>> Requiring reg/reg-names/phy-cells should be in separate patch with its
>> own reasoning.
> Ok, I will create two separate patches and add if:then clause only for 
> tegra234.
> As per understanding final change will look like below, right?
> 
> 
> required:
>    - reg
>    - reg-names
>    - '#phy-cells'
> 
> allOf:
>    - if:
>        properties:
>          compatible:
>            contains:
>              enum:
>                - nvidia,tegra234-p2u
>      then:
>        required:
>          - interrupts
>          - nvidia,bpmp

yes

Best regards,
Krzysztof