On 14/08/2022 16:47, Conor.Dooley@xxxxxxxxxxxxx wrote:
> On 12/08/2022 08:35, Krzysztof Kozlowski wrote:
>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>>
>> On 11/08/2022 23:33, Conor Dooley wrote:
>>> From: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
>>>
>>> Upgrading dt-schema to v2022.08 reveals unevaluatedProperties issues
>>> that were not previously visible, such as the missing clocks and
>>> clock-names properties for PolarFire SoC's PCI controller:
>>> arch/riscv/boot/dts/microchip/mpfs-icicle-kit.dtb: pcie@2000000000: Unevaluated properties are not allowed ('clock-names', 'clocks', 'legacy-interrupt-controller', 'microchip,axi-m-atr0' were unexpected)
>>> From schema: Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
>>>
>>> The clocks are required to enable interfaces between the FPGA fabric
>>> and the core complex, so add them to the binding.
>>>
>>> Fixes: 6ee6c89aac35 ("dt-bindings: PCI: microchip: Add Microchip PolarFire host binding")
>>> Signed-off-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
>>> ---
>>> .../bindings/pci/microchip,pcie-host.yaml | 25 +++++++++++++++++++
>>> 1 file changed, 25 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml b/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
>>> index edb4f81253c8..2a2166f09e2c 100644
>>> --- a/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
>>> +++ b/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
>>> @@ -25,6 +25,31 @@ properties:
>>> - const: cfg
>>> - const: apb
>>>
>>> + clocks:
>>> + description:
>>> + Fabric Interface Controllers, FICs, are the interface between the FPGA
>>> + fabric and the core complex on PolarFire SoC. The FICs require two clocks,
>>> + one from each side of the interface. The "FIC clocks" described by this
>>> + property are on the core complex side & communication through a FIC is not
>>> + possible unless it's corresponding clock is enabled. A clock must be
>>> + enabled for each of the interfaces the root port is connected through.
>>> + minItems: 1
>>> + items:
>>> + - description: FIC0's clock
>>> + - description: FIC1's clock
>>> + - description: FIC2's clock
>>> + - description: FIC3's clock
>>> +
>>> + clock-names:
>>> + items:
>>> + enum:
>>> + - fic0
>>> + - fic1
>>> + - fic2
>>> + - fic3
>>> + minItems: 1
>>> + maxItems: 4
>>
>> No need for maxItems.
>
> I brought this up on IRC, but transferring it here since it's been
> an (understandable!!) few days & just didn't want things to get lost
> if my net died. Cutting out the back & forth, in summary:
> "
> I'm trying to remove the maxItems from the clock-names array you
> didn't like - but I can't figure out what to do instead that doesn't
> trigger errors. All 4 clocks are optional, the only requirement is
> that any one of them is present. Either I seem to get complaints that
> my property is not an array (simply removing the maxItems) or complaints
> that because I have clock0,1,3 and not 2 that clock3 is unexpected.
Eh, I misread the code and thought that you list the items, but you just
enumerate the schema for each item. My advice was wrong, you need maxItems.
> The root port is physically on the opposite side of the FPGA to the cpus
> & the AXI connection is through the FPGA fabric. There are 4 AXI
> interconnects to the fabric which the PCI controller could in theory be
> connected to all 4, but it only needs to be connected to one.. I had
> done done minItems and maxItems a la:
> devicetree/bindings/watchdog/st,stm32-iwdg.yaml
> b/c that seems to have two clocks that it doesnt care about the order of
> "
>
> Rob then suggested:
> "
> I would remove the 'items' list in 'clocks' and make the description
> clear that any of clocks is possible. It's not ideal, but it's a case of
> that's what is already there.
> "
>
> I'd then have something along the lines of:
> clocks:
> description:
> Fabric Interface Controllers, FICs, are the interface between the FPGA
> fabric and the core complex on PolarFire SoC. The FICs require two clocks,
> one from each side of the interface. The "FIC clocks" described by this
> property are on the core complex side & communication through a FIC is not
> possible unless it's corresponding clock is enabled. A clock must be
> enabled for each of the interfaces the root port is connected through.
> This could in theory be all 4 interfaces, one interface or any combination
> in between.
> minItems: 1
> maxItems: 4
>
> clock-names:
> items:
> enum:
> - fic0
> - fic1
> - fic2
> - fic3
> minItems: 1
> maxItems: 4
>
> Does that seem reasonable to you?
Yes.
Best regards,
Krzysztof
