Re: [RFC PATCH v2 2/2] dt-bindings: cpufreq: Document Krait CPU Cache scaling

Sudeep Holla
2020-08-10T08:01:58Z

On Sat, Aug 08, 2020 at 01:49:12AM +0200, Ansuel Smith wrote:
> Document dedicated Krait CPU Cache Scaling driver.
>
> Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
> ---
> .../bindings/cpufreq/krait-cache-scale.yaml | 92 +++++++++++++++++++
> 1 file changed, 92 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/cpufreq/krait-cache-scale.yaml
>
> diff --git a/Documentation/devicetree/bindings/cpufreq/krait-cache-scale.yaml b/Documentation/devicetree/bindings/cpufreq/krait-cache-scale.yaml
> new file mode 100644
> index 000000000000..f10b1f386a99
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/cpufreq/krait-cache-scale.yaml
> @@ -0,0 +1,92 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/cpufreq/krait-cache-scale.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Krait Cpu Cache Frequency Scaling dedicated driver
> +
> +maintainers:
> + - Ansuel Smith <ansuelsmth@gmail.com>
> +
> +description: |
> + This Scale the Krait CPU Cache Frequency and optionally voltage
> + when the Cpu Frequency is changed (using the cpufreq notifier).
> +
> + Cache is scaled with the max frequency across all core and the cache
> + frequency will scale based on the configured threshold in the dts.
> +
> + The cache is hardcoded to 3 frequency bin, idle, nominal and high.
> +
> +properties:
> + compatible:
> + const: qcom,krait-cache
> +

How does this fit in the standard cache hierarchy nodes ? Extend the
example to cover that.

> + clocks:
> + description: Phandle to the L2 CPU clock
> +
> + clock-names:
> + const: "l2"
> +
> + voltage-tolerance:
> + description: Same voltage tollerance of the Krait CPU
> +
> + l2-rates:
> + description: |
> + Frequency the L2 cache will be scaled at.
> + Value is in Hz.
> + $ref: /schemas/types.yaml#/definitions/uint32-array
> + items:
> + - description: idle
> + - description: nominal
> + - description: high
> +

Why can't you re-use the standard OPP v2 bindings ?

--
Regards,
Sudeep