Re: [PATCH 3/6] dt-bindings: pci/qcom-pcie: specify reg-names explicitly

[Dmitry Baryshkov <dmitry.baryshkov@linaro.org>]

On 22/04/2022 18:51, Krzysztof Kozlowski wrote:
> On 22/04/2022 17:47, Dmitry Baryshkov wrote:
>> On Fri, 22 Apr 2022 at 15:55, Krzysztof Kozlowski
>> <krzysztof.kozlowski@linaro.org> wrote:
>>>
>>> On 22/04/2022 13:48, Dmitry Baryshkov wrote:
>>>> Instead of specifying the enum of possible reg-names, specify them
>>>> explicitly. This allows us to specify which chipsets need the "atu"
>>>> regions, which do not. Also it clearly describes which platforms
>>>> enumerate PCIe cores using the dbi region and which use parf region for
>>>> that.
>>>>
>>>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>>>> ---
>>>>   .../devicetree/bindings/pci/qcom,pcie.yaml    | 96 ++++++++++++++++---
>>>>   1 file changed, 81 insertions(+), 15 deletions(-)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
>>>> index 7210057d1511..e78e63ea4b25 100644
>>>> --- a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
>>>> +++ b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
>>>> @@ -35,21 +35,6 @@ properties:
>>>>             - qcom,pcie-ipq6018
>>>>         - const: snps,dw-pcie
>>>>
>>>> -  reg:
>>>> -    minItems: 4
>>>> -    maxItems: 5
>>>
>>> This should stay.
>>>
>>>> -
>>>> -  reg-names:
>>>> -    minItems: 4
>>>> -    maxItems: 5
>>>> -    items:
>>>> -      enum:
>>>> -        - parf # Qualcomm specific registers
>>>> -        - dbi # DesignWare PCIe registers
>>>> -        - elbi # External local bus interface registers
>>>> -        - config # PCIe configuration space
>>>> -        - atu # ATU address space (optional)
>>>
>>> Move one of your lists for specific compatibles here and name last
>>> element optional (minItems: 4).
>>>
>>> You will need to fix the order of regs in DTS to match the one defined here.
>>
>> I see your idea. I wanted to be explicit, which platforms need atu and
>> which do not. You'd prefer not to.
> 
> Opposite, I wish platforms to be specific, which need atu which not.
> However I wish the strictly defined, same order for everyone because it
> looks possible.

Well, the same order is not possible, since for some devices the first, 
address-defining reg is "parf", for others it is "dbi". So, there will 
be two "families" of the devices. Unless we want to change the DT 
address of the unit.

>> Let's probably drop this for now. The bindings proposed in patch 1
>> work for now. I will work on updating reg-names later.
> 
> 
> Best regards,
> Krzysztof


-- 
With best wishes
Dmitry