Re: [PATCH v5 1/4] dt-bindings: rtc: add schema for NXP S32G2/S32G3 SoCs

From: Krzysztof Kozlowski
Date: Tue Nov 26 2024 - 14:11:10 EST


On 26/11/2024 12:49, Ciprian Costea wrote:
> +
> +title: NXP S32G2/S32G3 Real Time Clock (RTC)
> +
> +maintainers:
> + - Bogdan Hamciuc <bogdan.hamciuc@xxxxxxx>
> + - Ciprian Marian Costea <ciprianmarian.costea@xxxxxxx>
> +
> +description:
> + RTC hardware module present on S32G2/S32G3 SoCs is used as a wakeup source.
> + It is not kept alive during system reset and it is not battery-powered.

Does this mean that this is not a standard RTC thus standard RTC schema
does not apply?

> +
> +properties:
> + compatible:
> + oneOf:
> + - enum:
> + - nxp,s32g2-rtc
> + - items:
> + - const: nxp,s32g3-rtc
> + - const: nxp,s32g2-rtc
> +
> + reg:
> + maxItems: 1
> +
> + interrupts:
> + maxItems: 1
> +
> + clocks:
> + items:
> + - description: ipg clock drives the access to the RTC iomapped registers
> + - description: Clock source for the RTC module. Can be selected between
> + 4 different clock sources using an integrated hardware mux.
> + On S32G2/S32G3 SoCs, 'source0' is the SIRC clock (~32KHz) and it is
> + available during standby and runtime. 'source1' is reserved and cannot

I am not sure what are the benefits of allowing to choose a clock which
cannot be used. I think source1 should be dropped.

> + be used. 'source2' is the FIRC clock and it is only available during
> + runtime providing a better resolution (~48MHz). 'source3' is an external
> + RTC clock source which can be additionally added in hardware.
> +
> + clock-names:
> + items:
> + - const: ipg
> + - enum: [ source0, source1, source2, source3 ]
> +
Best regards,
Krzysztof