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

From: Rob Herring <robh@kernel.org>
To: Tero Kristo <t-kristo@ti.com>
Cc: wim@linux-watchdog.org, linux@roeck-us.net,
	linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org,
	devicetree@vger.kernel.org
Subject: Re: [PATCHv2 1/4] dt-bindings: watchdog: Add support for TI K3 RTI watchdog
Date: Tue, 10 Mar 2020 14:37:21 -0500	[thread overview]
Message-ID: <20200310193721.GA24150@bogus> (raw)
In-Reply-To: <20200302200426.6492-2-t-kristo@ti.com>

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@kernel.org>
> Cc: devicetree@vger.kernel.org
> Signed-off-by: Tero Kristo <t-kristo@ti.com>
> ---
>  .../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@ti.com>
> +
> +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
> 
> --
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