Re: [PATCH v6 4/6] ARM: dts: Renesas RZ/N1 SoC base device tree file

From: M P
Date: Wed May 23 2018 - 07:00:27 EST


Hi Geert,

On Wed, 23 May 2018 at 12:18, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
wrote:

> Hi Michel,

> On Wed, May 23, 2018 at 11:20 AM, M P <buserror@xxxxxxxxx> wrote:
> > On Wed, 23 May 2018 at 10:12, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> > wrote:
> >> On Tue, May 22, 2018 at 12:01 PM, Michel Pollet
> >> <michel.pollet@xxxxxxxxxxxxxx> wrote:
> >> > + #address-cells = <1>;
> >> > + #size-cells = <1>;
> >> > +
> >> > + cpus {
> >> > + #address-cells = <1>;
> >> > + #size-cells = <0>;
> >> > + clocks = <&clock RZN1_DIV_CA7>;
> >
> >> I think the clocks property should be moved to the individual CPU
nodes.
> >
> > Ah, I had a look around, and I found some instances that are in the cpu
> > sub-node, and others that are not -- it seems that having it in the cpu
> > sub-node would implies it's core specific... here if that clock is
changed
> > both cores would change speed...

> Assumed the driver code knows to look in the parent node, which I doubt
> the cpufreq code does.

> > Either way, it's not used by the kernel in any way at the moment -- I
had
> > hoped cpufreq or something would claim it, but it's not the case.

> I guess you have to add your main SoC compatible value to the whitelist
> in drivers/cpufreq/cpufreq-dt-platdev.c first.

Most excellent tip here -- I'll add a further patch to enable this, after
this series eventually gets merged...

Cheers,
Michel