Re: [PATCH 1/2] dt-bindings: Add mtk-systimer bindings

Stanley Chu
2018-06-26T06:36:24Z

On Mon, 2018-06-25 at 23:53 +0200, Daniel Lezcano wrote:
> On 25/06/2018 09:10, Stanley Chu wrote:
> > Add binding documentation for the System Timer driver of
> > the Mediatek SoCs.
> >
> > Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
> > ---
> > .../bindings/timer/mediatek,mtk-systimer.txt | 18 ++++++++++++++++++
> > 1 file changed, 18 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/timer/mediatek,mtk-systimer.txt
> >
> > diff --git a/Documentation/devicetree/bindings/timer/mediatek,mtk-systimer.txt b/Documentation/devicetree/bindings/timer/mediatek,mtk-systimer.txt
> > new file mode 100644
> > index 0000000..735a6fd
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/timer/mediatek,mtk-systimer.txt
> > @@ -0,0 +1,18 @@
> > +Mediatek System Timers
> > +----------------------
> > +
> > +Required properties:
> > +- compatible: should contain
> > + "mediatek,sys_timer" for those platforms which support system timer.
> > +- reg: Mandatory. The location and length for system timer registers.
> > +- clock-frequency: Optional. If not assigned specifically, default
> > + value 13000000 (means 13 MHz) would be applied.
>
> The driver tells there is an error if it is not defined, so it can't be
> optional.
>
> > +Examples:
> > +
> > + sys_timer@10017000 {
> > + compatible = "mediatek,sys_timer";
> > + reg = <0 0x10017000 0 0x1000>;
> > + interrupts = <GIC_SPI 194 IRQ_TYPE_LEVEL_HIGH>;
> > + clock-frequency = <13000000>;
>
> Replace it by a phandle to a 'fixed-clock'.
>
> eg.
>
> clocks = <&myclk>;
>
>
> > + };
>
> myclk: myclk {
> #clock-cells = <0>;
> compatible = "fixed-clock";
> clock-frequency = <13000000>;
> };
>
> Thanks
>
> -- DAniel
>
>
>
>
Hi Daniel,

13 MHz clock is necessary. We will fix it in v2 by using system's
fixed-clock.

Thanks.
Stanley Chu