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

From: Geert Uytterhoeven
Date: Wed May 23 2018 - 06:25:19 EST


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.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds