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

From: Rob Herring
Date: Mon Jul 13 2020 - 12:42:20 EST


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@xxxxxxxxxx>
> ---
> 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
>