Re: [PATCH 06/12] riscv: dts: allwinner: Add the D1 SoC base devicetree

From: Heiko Stübner
Date: Tue Aug 16 2022 - 05:55:41 EST


Am Dienstag, 16. August 2022, 09:49:58 CEST schrieb Jernej Škrabec:
> Dne torek, 16. avgust 2022 ob 09:41:45 CEST je Krzysztof Kozlowski napisal(a):
> > On 15/08/2022 08:08, Samuel Holland wrote:
> > > +
> > > + de: display-engine {
> > > + compatible = "allwinner,sun20i-d1-display-engine";
> > > + allwinner,pipelines = <&mixer0>, <&mixer1>;
> > > + status = "disabled";
> > > + };
> > > +
> > > + osc24M: osc24M-clk {
> >
> > lowercase
> >
> > > + compatible = "fixed-clock";
> > > + clock-frequency = <24000000>;
> >
> > This is a property of the board, not SoC.
>
> SoC needs 24 MHz oscillator for correct operation, so each and every board has
> it. Having it here simplifies board DT files.

I guess the oscillator is a separate component on each board, right?
And DT obvious is meant to describe the hardware - independently from
implementation-specific choices.

Starting to discuss which exceptions to allow then might lead to even more
exceptions.

Also having to look for a board-component in the soc dtsi also is surprising
if one gets to the party later on :-) .