Date:   Mon, 27 Dec 2021 12:23:52 -0400
From:   Rob Herring <robh@kernel.org>
To:     David Heidelberg <david@ixit.cz>
Cc:     Andy Gross <agross@kernel.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        ~okias/devicetree@lists.sr.ht, linux-arm-msm@vger.kernel.org,
        linux-kernel@vger.kernel.org, devicetree@vger.kernel.org
Subject: Re: [PATCH] dt-bindings: timer: convert MSM timer to yaml
Message-ID: <YcnomHO8isHkxVIQ@robh.at.kernel.org>
References: <20211224234607.109049-1-david@ixit.cz>
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On Sat, Dec 25, 2021 at 12:46:06AM +0100, David Heidelberg wrote:
> Convert Qualcomm MSM Timer to yaml format.
> 
> Signed-off-by: David Heidelberg <david@ixit.cz>
> 
> ---
> It has currently issue, that it fights with watchdog/qcom-wdt.yaml
> Both bindings and drivers use similar sets of compatibles and qcom-wdt
> isn't very strictly defined.

What a mess... They should be merged most likely.

> 
>  .../bindings/timer/qcom,msm-timer.txt         | 47 -----------
>  .../bindings/timer/qcom,msm-timer.yaml        | 78 +++++++++++++++++++
>  2 files changed, 78 insertions(+), 47 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/timer/qcom,msm-timer.txt
>  create mode 100644 Documentation/devicetree/bindings/timer/qcom,msm-timer.yaml
> 
> diff --git a/Documentation/devicetree/bindings/timer/qcom,msm-timer.txt b/Documentation/devicetree/bindings/timer/qcom,msm-timer.txt
> deleted file mode 100644
> index 5e10c345548f..000000000000
> --- a/Documentation/devicetree/bindings/timer/qcom,msm-timer.txt
> +++ /dev/null
> @@ -1,47 +0,0 @@
> -* MSM Timer
> -
> -Properties:
> -
> -- compatible : Should at least contain "qcom,msm-timer". More specific
> -               properties specify which subsystem the timers are paired with.
> -
> -               "qcom,kpss-timer" - krait subsystem
> -               "qcom,scss-timer" - scorpion subsystem
> -
> -- interrupts : Interrupts for the debug timer, the first general purpose
> -               timer, and optionally a second general purpose timer, and
> -               optionally as well, 2 watchdog interrupts, in that order.
> -
> -- reg : Specifies the base address of the timer registers.
> -
> -- clocks: Reference to the parent clocks, one per output clock. The parents
> -          must appear in the same order as the clock names.
> -
> -- clock-names: The name of the clocks as free-form strings. They should be in
> -               the same order as the clocks.
> -
> -- clock-frequency : The frequency of the debug timer and the general purpose
> -                    timer(s) in Hz in that order.
> -
> -Optional:
> -
> -- cpu-offset : per-cpu offset used when the timer is accessed without the
> -               CPU remapping facilities. The offset is
> -               cpu-offset + (0x10000 * cpu-nr).
> -
> -Example:
> -
> -       timer@200a000 {
> -               compatible = "qcom,scss-timer", "qcom,msm-timer";
> -               interrupts = <1 1 0x301>,
> -                            <1 2 0x301>,
> -                            <1 3 0x301>,
> -                            <1 4 0x301>,
> -                            <1 5 0x301>;
> -               reg = <0x0200a000 0x100>;
> -               clock-frequency = <19200000>,
> -                                 <32768>;
> -               clocks = <&sleep_clk>;
> -               clock-names = "sleep";
> -               cpu-offset = <0x40000>;
> -       };
> diff --git a/Documentation/devicetree/bindings/timer/qcom,msm-timer.yaml b/Documentation/devicetree/bindings/timer/qcom,msm-timer.yaml
> new file mode 100644
> index 000000000000..238eb985d0fb
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/timer/qcom,msm-timer.yaml
> @@ -0,0 +1,78 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/timer/qcom,msm-timer.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm MSM Timer
> +
> +maintainers:
> +  - Rob Herring <robh@kernel.org>
> +
> +properties:
> +  $nodename:
> +    pattern: '^timer@[a-f0-9]+$'
> +
> +  compatible:
> +    oneOf:
> +      - items:
> +          - const: qcom,kpss-timer
> +          - enum:
> +              - qcom,kpss-wdt-apq8064
> +              - qcom,kpss-wdt-ipq8064
> +              - qcom,kpss-wdt-msm8960

Wrong order here. qcom,kpss-timer should be after these as it is less 
specific.
> +          - const: qcom,msm-timer

Drop this compatible string. It is unused and pointless.

> +      - items:
> +          - enum:
> +              - qcom,kpss-timer  # Krait subsystem
> +              - qcom,scss-timer  # Scorpion subsystem
> +          - const: qcom,msm-timer
> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    minItems: 1
> +    items:
> +      - description: 1st purpose timer
> +      - description: 2nd general purpose timer
> +      - description: 1st watchdog interrupt
> +      - description: 2nd watchdog interrupt
> +      - description: 3nd watchdog interrupt
> +
> +  clocks: true

You must define how many.

> +
> +  clock-names: true
> +
> +  clock-frequency: true
> +
> +  cpu-offset:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: >
> +      Per-cpu offset used when the timer is accessed without the
> +      CPU remapping facilities. The offset is cpu-offset + (0x10000 * cpu-nr).
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - clock-frequency
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    timer@200a000 {
> +        compatible = "qcom,scss-timer", "qcom,msm-timer";
> +        interrupts = <1 1 0x301>,
> +                     <1 2 0x301>,
> +                     <1 3 0x301>,
> +                     <1 4 0x301>,
> +                     <1 5 0x301>;
> +        reg = <0x0200a000 0x100>;
> +        clock-frequency = <19200000>,
> +                          <32768>;
> +        clocks = <&sleep_clk>;
> +        clock-names = "sleep";
> +        cpu-offset = <0x40000>;
> +    };
> -- 
> 2.34.1
> 
>