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 <20230607124628.157465-10-ulf.hansson@linaro.org> <20230614230044.GA3019052-robh@kernel.org>
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From:   Ulf Hansson <ulf.hansson@linaro.org>
Date:   Thu, 15 Jun 2023 11:10:38 +0200
Message-ID: <CAPDyKFoDQ12yUB-3f_V222kcUivP_NUcvcM+8s7CraLaBy7tBQ@mail.gmail.com>
Subject: Re: [PATCH 09/16] dt-bindings: firmware: arm,scmi: Extend bindings
 for protocol@13
To:     Rob Herring <robh@kernel.org>
Cc:     Sudeep Holla <sudeep.holla@arm.com>,
        Cristian Marussi <cristian.marussi@arm.com>,
        Viresh Kumar <vireshk@kernel.org>, Nishanth Menon <nm@ti.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Nikunj Kela <nkela@quicinc.com>,
        Prasad Sodagudi <psodagud@quicinc.com>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>, devicetree@vger.kernel.org
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On Thu, 15 Jun 2023 at 01:00, Rob Herring <robh@kernel.org> wrote:
>
> On Wed, Jun 07, 2023 at 02:46:21PM +0200, Ulf Hansson wrote:
> > The protocol@13 node is describing the performance scaling option for the
> > ARM SCMI interface, as a clock provider. This is unnecessary limiting, as
> > performance scaling is in many cases not limited to switching a clock's
> > frequency.
> >
> > Therefore, let's extend the binding so the interface can be modelled as a
> > generic "performance domain" too. The common way to describe this, is to
> > use the "power-domain" bindings, so let's use that.
>
> What's wrong with the performance-domain binding?

In my opinion I think the performance-domain binding is superfluous.
We already have plenty of power-domains that do performance scaling
too - and they stick with the power-domain binding, as it's
sufficient.

That said, I would rather follow the defacto standard that has been
used for many years in the kernel. Do you have a preference that we
should stick to?

Kind regards
Uffe

>
> >
> > Cc: Rob Herring <robh+dt@kernel.org>
> > Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
> > Cc: Conor Dooley <conor+dt@kernel.org>
> > Cc: devicetree@vger.kernel.org
> > Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
> > ---
> >  Documentation/devicetree/bindings/firmware/arm,scmi.yaml | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml
> > index 5824c43e9893..cff9d1e4cea1 100644
> > --- a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml
> > +++ b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml
> > @@ -145,8 +145,8 @@ properties:
> >        '#clock-cells':
> >          const: 1
> >
> > -    required:
> > -      - '#clock-cells'
> > +      '#power-domain-cells':
> > +        const: 1
> >
> >    protocol@14:
> >      $ref: '#/$defs/protocol-node'
> > --
> > 2.34.1
> >