RE: [PATCH] ARM: dts: imx7ulp: Add cpu clock-frequency property

From: Anson Huang
Date: Mon Dec 02 2019 - 20:09:30 EST



> Subject: Re: [PATCH] ARM: dts: imx7ulp: Add cpu clock-frequency property
>
> On Tue, Nov 05, 2019 at 09:49:38AM +0800, Anson Huang wrote:
> > Add "clock-frequency" property to avoid below warning on i.MX7ULP:
> >
> > [ 0.011762] /cpus/cpu@0 missing clock-frequency property
> >
> > Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
> > ---
> > arch/arm/boot/dts/imx7ulp.dtsi | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/arm/boot/dts/imx7ulp.dtsi
> > b/arch/arm/boot/dts/imx7ulp.dtsi index d37a192..87b2237 100644
> > --- a/arch/arm/boot/dts/imx7ulp.dtsi
> > +++ b/arch/arm/boot/dts/imx7ulp.dtsi
> > @@ -41,6 +41,7 @@
> > compatible = "arm,cortex-a7";
> > device_type = "cpu";
> > reg = <0>;
> > + clock-frequency = <500210526>;
>
> I cannot find the binding doc for this property. What is the definition of it,
> the maximum frequency that the cpu could possibly run at?


The code is as below, maybe the property is missing from the beginning of this code,
this property should mean the current frequency of CPU running at I think:

arch/arm/kernel/topology.c

122 rate = of_get_property(cn, "clock-frequency", &len);
123 if (!rate || len != 4) {
124 pr_err("%pOF missing clock-frequency property\n", cn);
125 continue;
126 }

Thanks,
Anson