linux-kernel - Re: [PATCH v8 1/2] dt-bindings: timer: Add bindings for Intel Keem Bay SoC Timer

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 22 Feb 2022 17:13:41 -0600
From:   Rob Herring <robh@...nel.org>
To:     shruthi.sanil@...el.com
Cc:     daniel.lezcano@...aro.org, tglx@...utronix.de,
        linux-kernel@...r.kernel.org, devicetree@...r.kernel.org,
        andriy.shevchenko@...ux.intel.com, mgross@...ux.intel.com,
        srikanth.thokala@...el.com, lakshmi.bai.raja.subramanian@...el.com,
        mallikarjunappa.sangannavar@...el.com
Subject: Re: [PATCH v8 1/2] dt-bindings: timer: Add bindings for Intel Keem
 Bay SoC Timer

On Tue, Feb 22, 2022 at 03:26:53PM +0530, shruthi.sanil@...el.com wrote:
> From: Shruthi Sanil <shruthi.sanil@...el.com>
> 
> Add Device Tree bindings for the Timer IP, which can be used as
> clocksource and clockevent device in the Intel Keem Bay SoC.
> 
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@...el.com>
> Signed-off-by: Shruthi Sanil <shruthi.sanil@...el.com>
> ---
>  .../bindings/timer/intel,keembay-timer.yaml   | 128 ++++++++++++++++++
>  1 file changed, 128 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/timer/intel,keembay-timer.yaml
> 
> diff --git a/Documentation/devicetree/bindings/timer/intel,keembay-timer.yaml b/Documentation/devicetree/bindings/timer/intel,keembay-timer.yaml
> new file mode 100644
> index 000000000000..9e6d46ecc2dc
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/timer/intel,keembay-timer.yaml
> @@ -0,0 +1,128 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/timer/intel,keembay-timer.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Intel Keem Bay SoC Timers
> +
> +maintainers:
> +  - Shruthi Sanil <shruthi.sanil@...el.com>
> +
> +description: |
> +  The Intel Keem Bay timer driver supports 1 free running counter and 8 timers.

Bindings describe the h/w, not what drivers support.

> +  Each timer is capable of generating inividual interrupt.
> +  Both the features are enabled through the timer general config register.
> +
> +  The parent node represents the common general configuration details and
> +  the child nodes represents the counter and timers.
> +
> +properties:
> +  compatible:
> +    oneOf:
> +      - items:

Don't need oneOf with only 1 entry.

> +          - enum:
> +              - intel,keembay-gpt-creg
> +          - const: simple-mfd
> +
> +  reg:
> +    description: General configuration register address and length.
> +    maxItems: 1
> +
> +  ranges: true
> +
> +  "#address-cells":
> +    const: 1
> +
> +  "#size-cells":
> +    const: 1
> +
> +required:
> +  - compatible
> +  - reg
> +  - ranges
> +  - "#address-cells"
> +  - "#size-cells"
> +
> +patternProperties:
> +  "^counter@[0-9a-f]+$":
> +    description: Properties for Intel Keem Bay counter.
> +    type: object
> +    properties:
> +      compatible:
> +        oneOf:

Don't need oneOf.

> +          - items:
> +              - enum:
> +                  - intel,keembay-counter
> +
> +      reg:
> +        maxItems: 1
> +
> +      clocks:
> +        maxItems: 1
> +
> +    required:
> +      - compatible
> +      - reg
> +      - clocks
> +
> +  "^timer@[0-9a-f]+$":
> +    description: Properties for Intel Keem Bay timer
> +    type: object
> +    properties:
> +      compatible:
> +        oneOf:
> +          - items:
> +              - enum:
> +                  - intel,keembay-timer
> +
> +      reg:
> +        maxItems: 1
> +
> +      interrupts:
> +        maxItems: 1
> +
> +      clocks:
> +        maxItems: 1
> +
> +    required:
> +      - compatible
> +      - reg
> +      - interrupts
> +      - clocks
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +    #define KEEM_BAY_A53_TIM
> +
> +    soc {
> +        #address-cells = <0x2>;
> +        #size-cells = <0x2>;
> +
> +        gpt@...31000 {
> +            compatible = "intel,keembay-gpt-creg", "simple-mfd";

It looks like you are splitting things based on Linux implementation 
details. Does this h/w block have different combinations of timers and 
counters? If not, then you don't need the child nodes at all. There's 
plenty of h/w blocks that get used as both a clocksource and clockevent.

Maybe I already raised this, but assume I don't remember and this patch 
needs to address any questions I already asked.

> +            reg = <0x0 0x20331000 0x0 0xc>;
> +            ranges = <0x0 0x0 0x20330000 0xF0>;
> +            #address-cells = <0x1>;
> +            #size-cells = <0x1>;
> +
> +            counter@e8 {
> +                compatible = "intel,keembay-counter";
> +                reg = <0xe8 0x8>;
> +                clocks = <&scmi_clk KEEM_BAY_A53_TIM>;
> +            };
> +
> +            timer@30 {
> +                compatible = "intel,keembay-timer";
> +                reg = <0x30 0xc>;
> +                interrupts = <GIC_SPI 0x5 IRQ_TYPE_LEVEL_HIGH>;
> +                clocks = <&scmi_clk KEEM_BAY_A53_TIM>;
> +            };
> +        };
> +    };
> +
> +...
> -- 
> 2.17.1
> 
>