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

From: [email-masked] (Michael Turquette)
Date: Mon, 29 Jun 2015 14:53:40 -0700

Quoting Viresh Kumar (2015-06-23 18:06:21)
> 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 <[email-masked]> wrote:
> > > This patch adds device tree binding document for MT8173 cpufreq driver.
> > >
> > > Signed-off-by: Pi-Cheng Chen <[email-masked]>
> > > ---
> > >  .../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.

Everything looks good. This is a typical clock consumer based on the
generic clock-binding. You might want to reference that this cpufreq
binding uses the "Clock consumers" portion of the clock binding and
reference its location:

Documentation/devicetree/bindings/clock/clock-bindings.txt

Please add,

Reviewed-by: Michael Turquette <[email-masked]>

Thanks,
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