Re: [PATCH 1/2] dt-bindings: mediatek: Add MT8173 cpufreq driver binding
From: Michael Turquette
Date: Mon Jun 29 2015 - 17:54:15 EST
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 <pi-cheng.chen@xxxxxxxxxx> wrote:
> > > This patch adds device tree binding document for MT8173 cpufreq driver.
> > >
> > > Signed-off-by: Pi-Cheng Chen <pi-cheng.chen@xxxxxxxxxx>
> > > ---
> > > .../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 <mturquette@xxxxxxxxxxxx>
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@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@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@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@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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