Re: [PATCH] dt-bindings: marvell: Update Armada 37xx platform bindings

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 09/08/2022 16:13, Pali Rohár wrote:
> On Tuesday 09 August 2022 08:58:50 Krzysztof Kozlowski wrote:
>> On 08/08/2022 23:23, Pali Rohár wrote:
>>> PING?
>>>
>>> On Wednesday 13 July 2022 22:01:23 Pali Rohár wrote:
>>>> Distinguish between Armada 3700 family, Armada 3710 SoC and Armada 3720 SoC.
>>>> Armada 3720 DB is name of the board with Armada 3720 SoC, so correctly
>>>> indicate SoC in example.
>>>>
>>>> Signed-off-by: Pali Rohár <pali@kernel.org>
>>>> ---
>>>>  .../devicetree/bindings/arm/marvell/armada-37xx.txt        | 7 ++++++-
>>>>  1 file changed, 6 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/arm/marvell/armada-37xx.txt b/Documentation/devicetree/bindings/arm/marvell/armada-37xx.txt
>>>> index f6d6642d81c0..d2ca008de266 100644
>>>> --- a/Documentation/devicetree/bindings/arm/marvell/armada-37xx.txt
>>>> +++ b/Documentation/devicetree/bindings/arm/marvell/armada-37xx.txt
>>>> @@ -4,6 +4,11 @@ Marvell Armada 37xx Platforms Device Tree Bindings
>>>>  Boards using a SoC of the Marvell Armada 37xx family must carry the
>>>>  following root node property:
>>>>  
>>>> + - compatible: must contain "marvell,armada3700"
>>>> +
>>>> +In addition, boards using the Marvell Armada 3710 SoC shall have the
>>>> +following property before the previous one:
>>>> +
>>
>> The change is an ABI break, which looks reasonable, but still platform
>> maintainer should comment on it. Especially on the aspect why the
>> marvell,armada3710 fallback was chosen at the first place.
> 
> I do not think this is ABI break but rather incorrect documentation and
> bug in some board dts files.

This documentation is the ABI, especially if actually implemented in the
DTS files, therefore by all definitions of DT ABI this is an ABI break.

What you are saying about "incorrect documentation and bug in some DTS
files" is a good reason to break the ABI, but it is still a break.

Best regards,
Krzysztof