linux-kernel - Re: [PATCH v5 2/4] dt-bindings: opp: opp-v2-kryo-cpu: Document named opp-microvolt property

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Date:   Mon, 2 Oct 2023 21:10:35 +0200
From:   Christian Marangi <ansuelsmth@...il.com>
To:     Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
Cc:     Robert Marko <robimarko@...il.com>, ilia.lin@...nel.org,
        vireshk@...nel.org, nm@...com, sboyd@...nel.org,
        robh+dt@...nel.org, krzysztof.kozlowski+dt@...aro.org,
        conor+dt@...nel.org, agross@...nel.org, andersson@...nel.org,
        konrad.dybcio@...aro.org, rafael@...nel.org,
        linux-pm@...r.kernel.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-arm-msm@...r.kernel.org
Subject: Re: [PATCH v5 2/4] dt-bindings: opp: opp-v2-kryo-cpu: Document named
 opp-microvolt property

On Mon, Oct 02, 2023 at 10:07:44PM +0300, Dmitry Baryshkov wrote:
> On Sat, 30 Sept 2023 at 13:22, Robert Marko <robimarko@...il.com> wrote:
> >
> > From: Christian Marangi <ansuelsmth@...il.com>
> >
> > Document named opp-microvolt property for opp-v2-kryo-cpu schema.
> > This property is used to declare multiple voltage ranges selected on the
> > different values read from efuses. The selection is done based on the
> > speed pvs values and the named opp-microvolt property is selected by the
> > qcom-cpufreq-nvmem driver.
> >
> > Signed-off-by: Christian Marangi <ansuelsmth@...il.com>
> > Signed-off-by: Robert Marko <robimarko@...il.com>
> > ---
> > Changes v5:
> > * Fix typo in opp items
> >
> > Changes v4:
> > * Address comments from Rob (meaning of pvs, drop of
> >   driver specific info, drop of legacy single voltage OPP,
> >   better specify max regulators supported)
> >
> >  .../bindings/opp/opp-v2-kryo-cpu.yaml         | 39 +++++++++++++++++++
> >  1 file changed, 39 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/opp/opp-v2-kryo-cpu.yaml b/Documentation/devicetree/bindings/opp/opp-v2-kryo-cpu.yaml
> > index 27ea7eca73e5..8d2a47e9a854 100644
> > --- a/Documentation/devicetree/bindings/opp/opp-v2-kryo-cpu.yaml
> > +++ b/Documentation/devicetree/bindings/opp/opp-v2-kryo-cpu.yaml
> > @@ -65,6 +65,12 @@ patternProperties:
> >            5:  MSM8996SG, speedbin 1
> >            6:  MSM8996SG, speedbin 2
> >            7-31:  unused
> > +
> > +          Bitmap for IPQ806X SoC:
> > +          0:  IPQ8062
> > +          1:  IPQ8064/IPQ8066/IPQ8068
> > +          2:  IPQ8065/IPQ8069
> > +          3-31:  unused
> >          enum: [0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7,
> >                 0x9, 0xd, 0xe, 0xf,
> >                 0x10, 0x20, 0x30, 0x70]
> > @@ -73,6 +79,23 @@ patternProperties:
> >
> >        required-opps: true
> >
> > +    patternProperties:
> > +      '^opp-microvolt-speed[0-9]+-pvs[0-9]+$':
> > +        description: |
> > +          Named opp-microvolt property following the same generic
> > +          binding for named opp-microvolt.
> > +
> > +          The correct voltage range is selected based on the values
> > +          in the efuse for the speed and the pvs (power variable
> > +          scaling).
> 
> I suppose that simple 'true' schema should be enough since this is
> already mostly described in opp/opp-v2-base.yaml
>

Mhhh an example of the following implementation?

> > +        minItems: 1
> > +        maxItems: 4 # Up to 4 regulators: Core, Mem, Dig and HFPLL
> > +        items:
> > +          items:
> > +            - description: nominal voltage
> > +            - description: minimum voltage
> > +            - description: maximum voltage
> > +
> >      required:
> >        - opp-hz
> >
> > @@ -258,6 +281,22 @@ examples:
> >              };
> >          };
> >
> > +        /* Dummy opp table to give example for named opp-microvolt */
> > +        opp-table-2 {
> > +            compatible = "operating-points-v2-kryo-cpu";
> > +            nvmem-cells = <&speedbin_efuse>;
> > +
> > +            opp-384000000 {
> > +                opp-hz = /bits/ 64 <384000000>;
> > +                opp-microvolt-speed0-pvs0 = <1000000 950000 1050000>;
> > +                opp-microvolt-speed0-pvs1 = <925000 878750 971250>;
> > +                opp-microvolt-speed0-pvs2 = <875000 831250 918750>;
> > +                opp-microvolt-speed0-pvs3 = <800000 760000 840000>;
> > +                opp-supported-hw = <0x7>;
> > +                clock-latency-ns = <100000>;
> > +            };
> > +        };
> > +
> >          smem {
> >              compatible = "qcom,smem";
> >              memory-region = <&smem_mem>;
> > --
> > 2.41.0
> >
> 
> 
> -- 
> With best wishes
> Dmitry

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