[PATCH 1/2] dt-bindings: mediatek: Add MT8173 cpufreq driver binding

Viresh Kumar viresh.kumar at linaro.org
Tue Jun 23 18:06:21 PDT 2015


Adding Mike's new email address..

On 23-06-15, 23:31, Pi-Cheng Chen wrote:
> On Mon, Jun 8, 2015 at 8:29 PM, Pi-Cheng Chen <pi-cheng.chen at linaro.org> wrote:
> > This patch adds device tree binding document for MT8173 cpufreq driver.
> >
> > Signed-off-by: Pi-Cheng Chen <pi-cheng.chen at linaro.org>
> > ---
> >  .../devicetree/bindings/cpufreq/cpufreq-mt8173.txt | 127 +++++++++++++++++++++
> >  1 file changed, 127 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/cpufreq/cpufreq-mt8173.txt
> >
> > diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-mt8173.txt b/Documentation/devicetree/bindings/cpufreq/cpufreq-mt8173.txt
> > new file mode 100644
> > index 0000000..7708a65
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-mt8173.txt
> > @@ -0,0 +1,127 @@
> > +
> > +Mediatek MT8173 cpufreq driver
> > +-------------------

Few more ---- required.

> > +
> > +Mediatek MT8173 cpufreq driver for CPU frequency scaling.
> > +
> > +Required properties:
> > +- clocks: A list of phandle + clock-specifier pairs for the clocks listed in clock names.
> > +- clock-names: Should contain the following:
> > +       "cpu"           - The multiplexer for clock input of CPU cluster.
> > +       "intermediate"  - A parent of "cpu" clock which is used as "intermediate" clock
> > +                         source (usually MAINPLL) when the original CPU PLL is under
> > +                         transition and not stable yet.

These belong to Mike.

> > +- operating-points: Table of frequencies and voltage CPU could be transitioned into,
> > +                   Frequency should be in KHz units and voltage should be in microvolts.

That's not complete. You should just mention the path to opp bindings
here. And that's it.

> > +- proc-supply: Regulator for Vproc of CPU cluster.
> > +
> > +Optional properties:
> > +- sram-supply: Regulator for Vsram of CPU cluster. When present, the cpufreq driver
> > +              needs to do "voltage trace" to step by step scale up/down Vproc and
> > +              Vsram to fit SoC specific needs. When absent, the voltage scaling
> > +              flow is handled by hardware, hence no software "voltage trace" is
> > +              needed.
> > +
> > +Example:
> > +--------
> > +       cpu0: cpu at 0 {
> > +               device_type = "cpu";
> > +               compatible = "arm,cortex-a53";
> > +               reg = <0x000>;
> > +               enable-method = "psci";
> > +               cpu-idle-states = <&CPU_SLEEP_0>;
> > +               clocks = <&infracfg CLK_INFRA_CA53SEL>,
> > +                        <&apmixedsys CLK_APMIXED_MAINPLL>;
> > +               clock-names = "cpu", "intermediate";
> > +               operating-points = <
> > +                       507000  859000
> > +                       702000  908000
> > +                       1001000 983000
> > +                       1105000 1009000
> > +                       1183000 1028000
> > +                       1404000 1083000
> > +                       1508000 1109000
> > +                       1573000 1125000
> > +               >;
> > +       };
> > +
> > +       cpu1: cpu at 1 {
> > +               device_type = "cpu";
> > +               compatible = "arm,cortex-a53";
> > +               reg = <0x001>;
> > +               enable-method = "psci";
> > +               cpu-idle-states = <&CPU_SLEEP_0>;
> > +               clocks = <&infracfg CLK_INFRA_CA53SEL>,
> > +                        <&apmixedsys CLK_APMIXED_MAINPLL>;
> > +               clock-names = "cpu", "intermediate";
> > +               operating-points = <
> > +                       507000  859000
> > +                       702000  908000
> > +                       1001000 983000
> > +                       1105000 1009000
> > +                       1183000 1028000
> > +                       1404000 1083000
> > +                       1508000 1109000
> > +                       1573000 1125000
> > +               >;
> > +       };
> > +
> > +       cpu2: cpu at 100 {
> > +               device_type = "cpu";
> > +               compatible = "arm,cortex-a57";
> > +               reg = <0x100>;
> > +               enable-method = "psci";
> > +               cpu-idle-states = <&CPU_SLEEP_0>;
> > +               clocks = <&infracfg CLK_INFRA_CA57SEL>,
> > +                        <&apmixedsys CLK_APMIXED_MAINPLL>;
> > +               clock-names = "cpu", "intermediate";
> > +               operating-points = <
> > +                       507000  828000
> > +                       702000  867000
> > +                       1001000 927000
> > +                       1209000 968000
> > +                       1404000 1007000
> > +                       1612000 1049000
> > +                       1807000 1089000
> > +                       1989000 1125000
> > +               >;
> > +       };
> > +
> > +       cpu3: cpu at 101 {
> > +               device_type = "cpu";
> > +               compatible = "arm,cortex-a57";
> > +               reg = <0x101>;
> > +               enable-method = "psci";
> > +               cpu-idle-states = <&CPU_SLEEP_0>;
> > +               clocks = <&infracfg CLK_INFRA_CA57SEL>,
> > +                        <&apmixedsys CLK_APMIXED_MAINPLL>;
> > +               clock-names = "cpu", "intermediate";
> > +               operating-points = <
> > +                       507000  828000
> > +                       702000  867000
> > +                       1001000 927000
> > +                       1209000 968000
> > +                       1404000 1007000
> > +                       1612000 1049000
> > +                       1807000 1089000
> > +                       1989000 1125000
> > +               >;
> > +       };

I remember Mark Rutland asking you about the replicated stuff for all
CPUs, but happened to his comments later on ? Were you asked to put
these for all the CPUs ?

-- 
viresh



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