Re: [PATCH 1/2] dt-bindings: PCI: xilinx-cpm: Add compatible string for CPM5 controller-1.

Krzysztof Kozlowski
2024-09-06T12:19:27Z

On 06/09/2024 12:50, Havalige, Thippeswamy wrote:
> Hi Krzysztof,
>
>> -----Original Message-----
>> From: Krzysztof Kozlowski <krzk@kernel.org>
>> Sent: Friday, September 6, 2024 4:16 PM
>> To: Havalige, Thippeswamy <thippeswamy.havalige@amd.com>;
>> manivannan.sadhasivam@linaro.org; robh@kernel.org; linux-
>> pci@vger.kernel.org; bhelgaas@google.com; linux-arm-
>> kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
>> krzk+dt@kernel.org; conor+dt@kernel.org; devicetree@vger.kernel.org
>> Cc: Gogada, Bharat Kumar <bharat.kumar.gogada@amd.com>; Simek,
>> Michal <michal.simek@amd.com>; lpieralisi@kernel.org; kw@linux.com
>> Subject: Re: [PATCH 1/2] dt-bindings: PCI: xilinx-cpm: Add compatible string
>> for CPM5 controller-1.
>>
>> On 06/09/2024 12:43, Havalige, Thippeswamy wrote:
>>> Hi Krzysztof
>>>
>>>> -----Original Message-----
>>>> From: Krzysztof Kozlowski <krzk@kernel.org>
>>>> Sent: Friday, September 6, 2024 3:26 PM
>>>> To: Havalige, Thippeswamy <thippeswamy.havalige@amd.com>;
>>>> manivannan.sadhasivam@linaro.org; robh@kernel.org; linux-
>>>> pci@vger.kernel.org; bhelgaas@google.com; linux-arm-
>>>> kernel@lists.infradead.org; linux-kernel@vger.kernel.org;
>>>> krzk+dt@kernel.org; conor+dt@kernel.org; devicetree@vger.kernel.org
>>>> Cc: Gogada, Bharat Kumar <bharat.kumar.gogada@amd.com>; Simek,
>> Michal
>>>> <michal.simek@amd.com>; lpieralisi@kernel.org; kw@linux.com
>>>> Subject: Re: [PATCH 1/2] dt-bindings: PCI: xilinx-cpm: Add compatible
>>>> string for CPM5 controller-1.
>>>>
>>>> On 06/09/2024 11:31, Thippeswamy Havalige wrote:
>>>>> The Xilinx Versal premium series has CPM5 block which supports two
>>>>> typeA Root Port controller functionality at Gen5 speed.
>>>>>
>>>>> Add compatible string to distinguish between two CPM5 rootport
>>>> controller1.
>>>>
>>>> Subjects NEVER end with full stops.
>>> Thanks, Update in the next patch series.
>>>>>
>>>>> Error interrupt register and bits for both the controllers are at
>>>>> different.
>>>>>
>>>>> Signed-off-by: Thippeswamy Havalige <thippesw@amd.com>
>>>>> ---
>>>>> Documentation/devicetree/bindings/pci/xilinx-versal-cpm.yaml | 1 +
>>>>> 1 file changed, 1 insertion(+)
>>>>>
>>>>> diff --git
>>>>> a/Documentation/devicetree/bindings/pci/xilinx-versal-cpm.yaml
>>>>> b/Documentation/devicetree/bindings/pci/xilinx-versal-cpm.yaml
>>>>> index 989fb0fa2577..b63a759ec2d7 100644
>>>>> --- a/Documentation/devicetree/bindings/pci/xilinx-versal-cpm.yaml
>>>>> +++ b/Documentation/devicetree/bindings/pci/xilinx-versal-cpm.yaml
>>>>> @@ -17,6 +17,7 @@ properties:
>>>>> enum:
>>>>> - xlnx,versal-cpm-host-1.00
>>>>> - xlnx,versal-cpm5-host
>>>>> + - xlnx,versal-cpm5-host1
>>>>
>>>> That's poor naming. "-1.00" and now "1". Get your naming reasonable...
>>> Here 1.00 represents the IP versioning and host1 represents controller-1.
>>
>> I understand but you repeating the same is not helping. Make it better and
>> next time upstream "host1-1" compatible.
>>
>> Number of ports, BTW, comes from ports, right? So no need for the
>> compatible.
>
> To differentiate between the registers for Controller-0 and Controller-1, I am utilizing a compatible string in the driver. This approach enables the driver to identify and manage the registers associated with each controller based on the specified compatible string.
>

Please don't state the obvious... I know how Linux kernel works. But
maybe I wasn't clear - do you have ports property there? I guess not, as
it is PCI.

What I claim here, is that you have exactly the same hardware. Same
hardware, same compatible.

Best regards,
Krzysztof