diff mbox series

ARM: dts: imx7ulp: Add cpu clock-frequency property

Message ID 1572918578-13544-1-git-send-email-Anson.Huang@nxp.com (mailing list archive)
State New, archived
Headers show
Series ARM: dts: imx7ulp: Add cpu clock-frequency property | expand

Commit Message

Anson Huang Nov. 5, 2019, 1:49 a.m. UTC
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@nxp.com>
---
 arch/arm/boot/dts/imx7ulp.dtsi | 1 +
 1 file changed, 1 insertion(+)

Comments

Shawn Guo Dec. 2, 2019, 1:47 p.m. UTC | #1
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@nxp.com>
> ---
>  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?

Shawn

>  		};
>  	};
>  
> -- 
> 2.7.4
>
Anson Huang Dec. 3, 2019, 1:09 a.m. UTC | #2
> 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@nxp.com>
> > ---
> >  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
Shawn Guo Dec. 4, 2019, 2:02 a.m. UTC | #3
+ Vincent

On Tue, Dec 03, 2019 at 01:09:22AM +0000, Anson Huang wrote:
> 
> > 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@nxp.com>
> > > ---
> > >  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                 }

Yes, I can find the code, but not bindings for it.  Considering
frequency of a CPU can be scaled in a quite wide range, we need
a clear understanding on this property.  IIUIC, the property is used to
calculate the capacity of CPU, it should be the maximum frequency the
CPU could possibly scale to?

Shawn
diff mbox series

Patch

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>;
 		};
 	};