Re: [PATCHv2 1/4] dt-bindings: watchdog: Add support for TI K3 RTI watchdog

From: Rob Herring
Date: Tue Mar 10 2020 - 15:37:25 EST


On Mon, Mar 02, 2020 at 10:04:23PM +0200, Tero Kristo wrote:
> TI K3 SoCs contain an RTI (Real Time Interrupt) module which can be
> used to implement a windowed watchdog functionality. Windowed watchdog
> will generate an error if it is petted outside the time window, either
> too early or too late.
>
> Cc: Rob Herring <robh@xxxxxxxxxx>
> Cc: devicetree@xxxxxxxxxxxxxxx
> Signed-off-by: Tero Kristo <t-kristo@xxxxxx>
> ---
> .../bindings/watchdog/ti,rti-wdt.yaml | 52 +++++++++++++++++++
> 1 file changed, 52 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml
>
> diff --git a/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml b/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml
> new file mode 100644
> index 000000000000..3813f59fb6c3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/watchdog/ti,rti-wdt.yaml
> @@ -0,0 +1,52 @@
> +# SPDX-License-Identifier: GPL-2.0

Dual license new bindings please:

(GPL-2.0-only OR BSD-2-Clause)

> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/watchdog/ti,rti-wdt.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Texas Instruments K3 SoC Watchdog Timer
> +
> +maintainers:
> + - Tero Kristo <t-kristo@xxxxxx>
> +
> +description: |+

You can drop '|+' as there's no formatting to preserve.

> + The TI K3 SoC watchdog timer is implemented via the RTI (Real Time
> + Interrupt) IP module. This timer adds a support for windowed watchdog
> + mode, which will signal an error if it is pinged outside the watchdog
> + time window, meaning either too early or too late. The error signal
> + generated can be routed to either interrupt a safety controller or
> + to directly reset the SoC.
> +

Reference the common watchdog.yaml schema.

> +properties:
> + compatible:
> + enum:
> + - ti,rti-wdt

Should be SoC specific possibly with a fallback.

> +
> + reg:
> + maxItems: 1
> +
> + clocks:
> + maxItems: 1
> +
> +required:
> + - compatible
> + - reg
> + - clocks
> +
> +examples:
> + - |
> + /*
> + * RTI WDT in main domain on J721e SoC. Assigned clocks are used to
> + * select the source clock for the watchdog, forcing it to tick with
> + * a 32kHz clock in this case.
> + */
> + #include <dt-bindings/soc/ti,sci_pm_domain.h>
> +
> + main_rti0: rti@2200000 {

watchdog@...

> + compatible = "ti,rti-wdt";
> + reg = <0x0 0x2200000 0x0 0x100>;
> + clocks = <&k3_clks 252 1>;
> + power-domains = <&k3_pds 252 TI_SCI_PD_EXCLUSIVE>;

Not documented.

> + assigned-clocks = <&k3_clks 252 1>;
> + assigned-clock-parents = <&k3_clks 252 5>;

Not documented.

> + };
> --
> 2.17.1
>
> --
> Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki