On 04/06/2025 12:05, Qiang Yu wrote: >>>>> Signed-off-by: Ziyue Zhang <quic_ziyuzhan@xxxxxxxxxxx> >>>>> --- >>>>> .../devicetree/bindings/pci/qcom,pcie-sa8775p.yaml | 13 +++++++++---- >>>>> 1 file changed, 9 insertions(+), 4 deletions(-) >>>>> >>>>> diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie-sa8775p.yaml b/Documentation/devicetree/bindings/pci/qcom,pcie-sa8775p.yaml >>>>> index e3fa232da2ca..805258cbcf2f 100644 >>>>> --- a/Documentation/devicetree/bindings/pci/qcom,pcie-sa8775p.yaml >>>>> +++ b/Documentation/devicetree/bindings/pci/qcom,pcie-sa8775p.yaml >>>>> @@ -61,11 +61,14 @@ properties: >>>>> - const: global >>>>> resets: >>>>> - maxItems: 1 >>>>> + minItems: 1 >>>>> + maxItems: 2 >>>> Shouldn't we just update this to maxItems:2 / minItems:2 and drop >>>> minItems:1 from the next clause? >>> Hi Dmitry, >>> >>> link_down reset is optional. In many other platforms, like sm8550 >>> and x1e80100, link_down reset is documented as a optional reset. >>> PCIe will works fine without link_down reset. So I think setting it >>> as optional is better. >> You are describing a hardware. How can a reset be optional in the >> _hardware_? It's either routed or not. > > I feel a bit confused. According to the theory above, everything seems to > be non-optional when describing hardware, such as registers, clocks, > resets, regulators, and interrupts—all of them either exist or do not. Can you construct a DTS being fully complete and correct picture of hardware without these? If not, they are not optional, because correct hardware representation would need them. > > Seems like I misunderstand the concept of 'optional'? Is 'optional' only > used for compatibility across different platforms? > > Additionally, we have documented the PCIe global interrupt as optional. I > was taught that, in the PCIe driver, this interrupt is retrieved using the > platform_get_irq_byname_optional API, so it can be documented as optional. > However, this still seems to contradict the theory mentioned earlier. ABI is just one side of the required properties. Best regards, Krzysztof
