Re: [PATCH v3 1/4] dt-bindings: clock: mediatek,mtmips-sysc: Adapt compatible for MT7688 boards

[Krzysztof Kozlowski <krzk@kernel.org>]

On 24/06/2025 11:08, Ezra Buehler wrote:
>> On 20 Jun 2025, at 09:42, Krzysztof Kozlowski <krzk@kernel.org> wrote:
>>
>> On Thu, Jun 19, 2025 at 10:34:59PM GMT, Ezra Buehler wrote:
>>> From: Ezra Buehler <ezra.buehler@husqvarnagroup.com>
>>>
>>> As the MT7628 and MT7688 are identical in most respects, mt7628a.dtsi is
>>> used for both SoCs. To prevent "Kernel panic - not syncing: unable to
>>> get CPU clock, err=-2" and allow an MT7688-based board to boot, the
>>> following must be allowed:
>>>
>>>    compatible = "ralink,mt7628-sysc", "ralink,mt7688-sysc", "syscon";
>>>
>>> Signed-off-by: Ezra Buehler <ezra.buehler@husqvarnagroup.com>
>>> ---
>>> .../bindings/clock/mediatek,mtmips-sysc.yaml  | 27 ++++++++++---------
>>> 1 file changed, 15 insertions(+), 12 deletions(-)
>>>
>>> diff --git a/Documentation/devicetree/bindings/clock/mediatek,mtmips-sysc.yaml b/Documentation/devicetree/bindings/clock/mediatek,mtmips-sysc.yaml
>>> index 83c1803ffd16..3fabaa8acc10 100644
>>> --- a/Documentation/devicetree/bindings/clock/mediatek,mtmips-sysc.yaml
>>> +++ b/Documentation/devicetree/bindings/clock/mediatek,mtmips-sysc.yaml
>>> @@ -26,18 +26,21 @@ description: |
>>>
>>> properties:
>>>   compatible:
>>> -    items:
>>> -      - enum:
>>> -          - ralink,mt7620-sysc
>>> -          - ralink,mt7628-sysc
>>> -          - ralink,mt7688-sysc
>>
>> I do not understand why this is removed and commit msg explains nothing
>> about it. Re-add it back.
> 
> OK, so you suggest we allow
> 
> compatible = "ralink,mt7628-sysc", "ralink,mt7688-sysc", "syscon";
> 
> and
> 
> compatible = "ralink,mt7688-sysc", "syscon";
> 
> I'll adapt my patch accordingly.
> 
> Still, as AFAIK the MT7628 and MT7688 are identical in this regard,

Standard rules apply expressed in writing bindings, some talks/guides
and all modern SoCs...


> 
> compatible = "ralink,mt7688-sysc", "ralink,mt7628-sysc", "syscon";
> 
> would technically be valid too. Could you elaborate why that is not a
> good idea? The MT7688 is basically a subset of the MT7628.

You did not send such patch.

Best regards,
Krzysztof