Re: [PATCH 1/2] dt-bindings: watchdog: intel: Add YAML Schemas for Watchdog timer

[Guenter Roeck <linux@roeck-us.net>]

On 6/7/20 10:49 PM, Dilip Kota wrote:
> Add YAML schemas for the watchdog timer on Intel Lightning
> Mountain SoC.
> 
> Signed-off-by: Dilip Kota <eswara.kota@linux.intel.com>
> ---
>  .../bindings/watchdog/intel,lgm-gptc-wdt.yaml      | 75 ++++++++++++++++++++++
>  1 file changed, 75 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/watchdog/intel,lgm-gptc-wdt.yaml
> 
> diff --git a/Documentation/devicetree/bindings/watchdog/intel,lgm-gptc-wdt.yaml b/Documentation/devicetree/bindings/watchdog/intel,lgm-gptc-wdt.yaml
> new file mode 100644
> index 0000000000000..83dc39a5090c1
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/watchdog/intel,lgm-gptc-wdt.yaml
> @@ -0,0 +1,75 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/watchdog/intel,lgm-gptc-wdt.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Intel Lightning Mountain Watchdog timer.
> +
> +maintainers:
> +  - Dilip Kota <eswara.kota@linux.intel.com>
> +
> +description: |
> +  Intel Lightning Mountain SoC has General Purpose Timer Counter(GPTC) which can
> +  be configured as Clocksource, real time clock and Watchdog timer.
> +  Each General Purpose Timer Counter has three timers. And total four General
> +  Purpose Timer Counters are present on Lightning Mountain SoC which sums up
> +  to 12 timers.
> +  Lightning Mountain has four CPUs and each CPU is configured with one GPTC
> +  timer as watchdog timer. Total four timers are configured as watchdog timers
> +  on Lightning Mountain SoC.
> +

Why not just one ? The watchdog subsystem does not monitor individual CPUs,
it monitors the system.

Guenter

> +allOf:
> +  - $ref: "watchdog.yaml#"
> +
> +properties:
> +  compatible:
> +    enum:
> +      - intel,lgm-gptc-wdt
> +
> +  reg:
> +    maxItems: 1
> +
> +  clocks:
> +    items:
> +      - description: Frequency clock
> +      - description: Core clock
> +
> +  clock-names:
> +    items:
> +      - const: freq
> +      - const: gptc
> +
> +  intel,wdt-rst-hndl:
> +    $ref: /schemas/types.yaml#/definitions/phandle
> +    description: Watchdog timer registers handle
> +
> +  intel,timer-cfg:
> +    description: Watchdog Timer id and CPU id
> +    allOf:
> +      - $ref: /schemas/types.yaml#/definitions/uint32-array
> +      - minItems: 2
> +        maxItems: 4
> +        items:
> +          minimum: 0
> +          maximum: 3
> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +  - clock-names
> +  - intel,wdt-rst-hndl
> +  - intel,timer-cfg
> +
> +examples:
> +  - |
> +    watchdog@e2500000 {
> +      compatible = "intel,lgm-gptc-wdt";
> +      reg = <0xe2500000 0x10000>;
> +      intel,wdt-rst-hndl = <&sysconf>;
> +      clocks = <&cgu0 31>, <&cgu0 136>;
> +      clock-names = "freq", "gptc";
> +      timeout-sec = <30>;
> +      intel,timer-cfg =  <1 0 2 1>;
> +    };
>