Re: [PATCH v3 03/14] dt-bindings: fsi: Document the FSI2PIB engine

Eddie James
2024-04-29T14:42:54Z

On 4/28/24 11:41, Krzysztof Kozlowski wrote:
> On 26/04/2024 17:00, Eddie James wrote:
>> On 4/26/24 01:18, Krzysztof Kozlowski wrote:
>>> On 25/04/2024 23:36, Eddie James wrote:
>>>> The FSI2PIB or SCOM engine provides an interface to the POWER processor
>>>> PIB (Pervasive Interconnect Bus).
>>>>
>>>> Signed-off-by: Eddie James <eajames@linux.ibm.com>
>>>> ---
>>>> .../devicetree/bindings/fsi/ibm,fsi2pib.yaml | 38 +++++++++++++++++++
>>>> 1 file changed, 38 insertions(+)
>>>> create mode 100644 Documentation/devicetree/bindings/fsi/ibm,fsi2pib.yaml
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/fsi/ibm,fsi2pib.yaml b/Documentation/devicetree/bindings/fsi/ibm,fsi2pib.yaml
>>>> new file mode 100644
>>>> index 000000000000..4d557150c2e3
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/fsi/ibm,fsi2pib.yaml
>>>> @@ -0,0 +1,38 @@
>>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>>> +%YAML 1.2
>>>> +---
>>>> +$id: http://devicetree.org/schemas/fsi/ibm,fsi2pib.yaml#
>>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>>> +
>>>> +title: IBM FSI-attached SCOM engine
>>>> +
>>>> +maintainers:
>>>> + - Eddie James <eajames@linux.ibm.com>
>>>> +
>>>> +description:
>>>> + The SCOM engine is an interface to the POWER processor PIB (Pervasive
>>>> + Interconnect Bus). This node will always be a child of an FSI CFAM node;
>>>> + see fsi.txt for details on FSI slave and CFAM nodes.
>>>> +
>>>> +properties:
>>>> + compatible:
>>>> + enum:
>>>> + - ibm,fsi2pib
>>>> + - ibm,i2cr-scom
>>> Sometimes you call these p9, sometimes p10... what is the system or SoC
>>> here? Aren't you adding some generic compatibles? writing-bindings and
>>> numerous guides are clear on that.
>>
>> Open source FSI support started with P9 chips so we initially added
>> p9-sbefifo, p9-occ, etc. P10 has all of the same engines as P9 plus the
>> SPI controller, so that's why SPI is p10-spi. P11 has the same engines
>> as P10. For scom/fsi2pib we could call it p9-scom I suppose... This
>> series isn't just documentation for a new system, I'm adding
>> documentation that should have been added for P9. Anyway I'm not sure
>> what you mean about generic compatibles? You mean just add a "scom" or
>> "fsi2pib" compatible? writing-bindings says "DO make 'compatible'
>> properties specific"
> Usually it means that parts of SoC must have the name of the SoC, as
> first component of the name. Your boards are a bit different here,
> because I suppose no one will ever make a product except you, but still
> code could follow same set of rules.

OK, this wasn't mentioned when fsi2spi binding was merged, and I thought
to make fsi2pib the same. I can switch to p9-scom or something.

Thanks,

Eddie

>
> Best regards,
> Krzysztof
>