Re: [PATCH 2/4] dt-bindings: net: dsa: Add SoC-e switch IP and DSA bindings

[Vasilij Strassheim <v.strassheim@linutronix.de>]

On Tue, 2026-08-04 at 08:25 +0200, Krzysztof Kozlowski wrote:
> On 03/08/2026 18:15, Vasilij Strassheim wrote:
> > On Thu, 2026-07-30 at 10:56 +0200, Krzysztof Kozlowski wrote:
> > > On Wed, Jul 29, 2026 at 06:36:55PM +0200, Vasilij Strassheim wrote:
> > > > Add DT schema documentation for SoC-e FPGA switch devices.
> > > > The binding is split into:
> > > >  - a switch IP node describing the MMIO register block
> > > >  - a DSA MDIO node describing the DSA-facing switch instance
> > > > Both nodes are linked through the soce,switch-ip phandle.
> > > > 
> > > > Signed-off-by: Vasilij Strassheim <v.strassheim@linutronix.de>
> > > > ---
> > > >  .../bindings/net/dsa/soce,switch-dsa.yaml          | 195 +++++++++++++++++++++
> > > >  .../bindings/net/dsa/soce,switch-ip.yaml           |  54 ++++++
> > > >  2 files changed, 249 insertions(+)
> > > > 
> > > > diff --git a/Documentation/devicetree/bindings/net/dsa/soce,switch-dsa.yaml b/Documentation/devicetree/bindings/net/dsa/soce,switch-dsa.yaml
> > > > new file mode 100644
> > > > index 000000000000..a04e2838d14e
> > > > --- /dev/null
> > > > +++ b/Documentation/devicetree/bindings/net/dsa/soce,switch-dsa.yaml
> > > 
[...]
> > > > +
> > > > +  compatible:
> > > > +    const: soce,switch-dsa
> > > 
> > > Way too generic. I understand that SoCe will NEVER - and you certify
> > > that - develop a second, different "switch-dsa" model and they call this
> > > one like this?
> > 
> > It is intentionally generic to cover the common basics of all variants and
> > configurations of the synthesized switch in DSA.
> 
> Compatible must not be generic, as expressed hundreds times and
> documented in writing bindings.

I probably misunderstood a few concepts around bindings, and I apologize
for that. For the next version, I would base it on the existing SoC-e IP
core families. Single DT binding file should then be sufficient.

I think a suitable filename would be something like soce,switch.yaml. That's
roughly in line with the existing nxp,netc-switch.yaml.
Or soce,swip.yaml, as in lantiq,gswip.yaml.

> 
> > I'm not sure what kind of guarantee I'm supposed to provide here regarding
> > SoCe. If switch-dsa is already mainline in the future, then a different
> > compatible will be needed for incompatible new models.
> 
> I also don't know what guarantee you must provide, it's you who wants to
> add an exception.

Okay, there's no need to make an exception for this case, I will change
the compatible to something suitable.

I also understand now, that the DT bindings are not necessarily used
only in Linux. However, I would like to use them for the DSA driver of the
Soft IP Core Switch. The driver can be adapted so that it reads a
wide variety of configurations and versions from the synthesized switch
and deal with them without any additional properties.

Would “soce,mrs” be suitable as “compatible” in this case? If that's
still too generic maybe “soce,mrs-switch-v1.0”
I will think more about it in the next few weeks, before I submit the
new version. Would be happy to hear any better suggestions that you, or
someone else, might have.

> ...
> 
> > > > +
> > > > +examples:
> > > > +  - |
> > > > +    switch_ip: switch@80020000 {
> > > 
> > > ethernet-switch
> > > 
> > > And drop unused label.
> > 
> > I will adjust it.
> > 
> > > 
> > > Considering this wasn't tested I should not even give here review...
> > > 
> > Thank you very much for the review!
> > I'm not sure what you mean by not tested. I ran make dt_binding_check` few
> > times, but forgot to do it after making the latest adjustments.
> 
> Untested as it has an obvious failure as reported by bot.

I know better now, that should not happen again in the future.

> 
> Best regards,
> Krzysztof

Thanks,
Vasilij