Re: [PATCH v6 09/52] dt-bindings: memory: tegra30: mc: Document new interconnect property

[Dmitry Osipenko]

27.10.2020 12:05, Krzysztof Kozlowski пишет:
> On Mon, Oct 26, 2020 at 01:16:52AM +0300, Dmitry Osipenko wrote:
>> Memory controller is interconnected with memory clients and with the
>> External Memory Controller. Document new interconnect property which
>> turns memory controller into interconnect provider.
>>
>> Acked-by: Rob Herring <robh@xxxxxxxxxx>
>> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
>> ---
>>  .../bindings/memory-controllers/nvidia,tegra30-mc.yaml       | 5 +++++
>>  1 file changed, 5 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra30-mc.yaml b/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra30-mc.yaml
>> index 84fd57bcf0dc..5436e6d420bc 100644
>> --- a/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra30-mc.yaml
>> +++ b/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra30-mc.yaml
>> @@ -57,6 +57,9 @@ properties:
>>    "#iommu-cells":
>>      const: 1
>>  
>> +  "#interconnect-cells":
>> +    const: 1
>> +
>>  patternProperties:
>>    "^emc-timings-[0-9]+$":
>>      type: object
>> @@ -120,6 +123,7 @@ required:
>>    - clock-names
>>    - "#reset-cells"
>>    - "#iommu-cells"
>> +  - "#interconnect-cells"
> 
> Rob,
> 
> You were fine with adding a new required property which breaks all
> existing DTBs?

This is a required property for the new bindings and optional for the
older. Does it really need to be made optional in the binding?

> Were these bindings marked as unstable? The patchset does not even
> say/scream that it breaks the ABI, so this might be quite a surprise for
> someone...

Please see tegra_mc_interconnect_setup() in "memory: tegra-mc: Add
interconnect framework" patch, which check presence of the new ICC DT
property.