Re: [PATCH 1/2] dt-bindings: watchdog: airoha: document watchdog for Airoha EN7581

From: Christian Marangi
Date: Thu Sep 19 2024 - 08:40:23 EST


On Thu, Sep 19, 2024 at 02:35:02PM +0200, Krzysztof Kozlowski wrote:
> On 19/09/2024 14:26, Christian Marangi wrote:
> > Document watchdog for Airoha EN7581. This SoC implement a simple
> > watchdog that supports a max timeout of 28 seconds.
> >
> > The watchdog ticks on half the BUS clock and require the BUS frequency
> > to be provided.
>
> Clock provider should implement clk_get_rate()...
>

The BUS clock is internal and not exposed to the system hence
clk_get_rate is not possible saddly.

> >
>
> ...
>
> > +maintainers:
> > + - Christian Marangi <ansuelsmth@xxxxxxxxx>
> > +
> > +allOf:
> > + - $ref: watchdog.yaml#
> > +
> > +properties:
> > + compatible:
> > + const: airoha,en7581-wdt
> > +
> > + reg:
> > + maxItems: 1
> > +
> > + clock-frequency:
> > + description: BUS frequency in Hz (timer ticks at half the BUS freq)
> > + const: 300000000
>
> Which bus frequency? Aren't you missing here clock input?

I'm putting here property to describe the internal clock to what the
watchdog is attached. Should I drop this and just hardcode it
internally to the driver or maybe declare the clock to be 150000000
directly?

Tick frequency is already not well defined so I tought it was a good
idea to describe it in DT.

--
Ansuel