linux-kernel - Re: [TEGRA194_CPUFREQ PATCH v5 1/4] dt-bindings: arm: Add t194 ccplex compatible and bpmp property

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]

Message-ID: <20200713164214.GA341271@bogus>
Date:   Mon, 13 Jul 2020 10:42:14 -0600
From:   Rob Herring <robh@...nel.org>
To:     Sumit Gupta <sumitg@...dia.com>
Cc:     rjw@...ysocki.net, viresh.kumar@...aro.org,
        catalin.marinas@....com, will@...nel.org, thierry.reding@...il.com,
        mirq-linux@...e.qmqm.pl, devicetree@...r.kernel.org,
        jonathanh@...dia.com, talho@...dia.com, linux-pm@...r.kernel.org,
        linux-tegra@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-kernel@...r.kernel.org, bbasu@...dia.com,
        mperttunen@...dia.com
Subject: Re: [TEGRA194_CPUFREQ PATCH v5 1/4] dt-bindings: arm: Add t194
 ccplex compatible and bpmp property

On Mon, Jul 13, 2020 at 07:36:46PM +0530, Sumit Gupta wrote:
> To do frequency scaling on all CPUs within T194 CPU Complex, we need
> to query BPMP for data on valid operating points. Document a compatible
> string under 'cpus' node to represent the CPU Complex for binding drivers
> like cpufreq which don't have their node or CPU Complex node to bind to.
> Also, document a property to point to the BPMP device that can be queried
> for all CPUs.

The cpus.yaml binding documents what's in 'cpu' nodes, not 'cpus' 
node. AIUI, the latter is what you want. You should do your own schema 
file here.

> 
> Signed-off-by: Sumit Gupta <sumitg@...dia.com>
> ---
>  Documentation/devicetree/bindings/arm/cpus.yaml | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/arm/cpus.yaml b/Documentation/devicetree/bindings/arm/cpus.yaml
> index a018147..9b328e3 100644
> --- a/Documentation/devicetree/bindings/arm/cpus.yaml
> +++ b/Documentation/devicetree/bindings/arm/cpus.yaml
> @@ -162,6 +162,7 @@ properties:
>        - nvidia,tegra132-denver
>        - nvidia,tegra186-denver
>        - nvidia,tegra194-carmel
> +      - nvidia,tegra194-ccplex

Tegra194 has 2 different CPUs?

>        - qcom,krait
>        - qcom,kryo
>        - qcom,kryo260
> @@ -255,6 +256,15 @@ properties:
>  
>        where voltage is in V, frequency is in MHz.
>  
> +  nvidia,bpmp:
> +    $ref: '/schemas/types.yaml#/definitions/phandle'
> +    description: |
> +      Specifies the bpmp node that needs to be queried to get
> +      operating point data for all CPUs.
> +
> +      Optional for systems that have a "compatible"
> +      property value of "nvidia,tegra194-ccplex".
> +
>    power-domains:
>      $ref: '/schemas/types.yaml#/definitions/phandle-array'
>      description:
> @@ -340,6 +350,7 @@ required:
>  
>  dependencies:
>    rockchip,pmu: [enable-method]
> +  nvidia,bpmp: [compatible]
>  
>  examples:
>    - |
> -- 
> 2.7.4
>