Re: [PATCH v3 1/6] dt-bindings: PCI: Add binding for qps615

Krishna Chaitanya Chundru
2025-01-07T14:28:38Z

On 12/30/2024 11:52 PM, Manivannan Sadhasivam wrote:
> On Mon, Dec 23, 2024 at 08:57:37PM +0200, Dmitry Baryshkov wrote:
>
> [...]
>
>>> This switch allows us to configure both upstream, downstream ports and
>>> also embedded Ethernet port which is internal to the switch. These
>>> properties are applicable for all of those.
>>>>> +
>>>>> + allOf:
>>>>> + - $ref: /schemas/pci/pci-bus.yaml#
>>>>
>>>> pci-pci-bridge.yaml is more specific and closer to what this device is.
>>>>
>>> I tried this now, I was getting warning saying the compatible
>>> /local/mnt/workspace/skales/kobj/Documentation/devicetree/bindings/pci/qcom,qps615.example.dtb:
>>> pcie@0,0: compatible: ['pci1179,0623'] does not contain items matching the
>>> given schema
>>> from schema $id: http://devicetree.org/schemas/pci/qcom,qps615.yaml#
>>> /local/mnt/workspace/skales/kobj/Documentation/devicetree/bindings/pci/qcom,qps615.example.dtb:
>>> pcie@0,0: Unevaluated properties are not allowed ('#address-cells',
>>> '#size-cells', 'bus-range', 'device_type', 'ranges' were unexpected)
>>>
>>> I think pci-pci-bridge is expecting the compatible string in this format
>>> only "pciclass,0604".
>>
>> I think the pci-pci-bridge schema requires to have "pciclass,0604" among
>> other compatibles. So you should be able to do something like:
>>
>> compatible = "pci1179,0623", "pciclass,0604";
>>
>
> Even though a PCIe switch is supposed to be a network of PCI bridges, using
> PCI bridge fallback for this switch is not technically correct IMO. Mostly
> because, this switch requires other configurations which are not applicable to
> PCI bridges. So the drivers matching against the bridge compatible won't be able
> to use this switch.
>
> - Mani
Rob,

Using pci-pci-bridge expects to use compatible as pciclass,0604, we
can't use as this switch is doing other configurations which are
applicable to PCI bridges. can we continue to use pci-bus.yaml.

- Krishna Chaitanya.
>