Re: [PATCH 01/10] dt-bindings: thermal: tegra: Document throttle temperature

Krzysztof Kozlowski
2023-04-14T21:48:03Z

On 14/04/2023 14:57, Thierry Reding wrote:
> From: Thierry Reding <treding@nvidia.com>
>
> Each throttling configuration needs to specify the temperature threshold
> at which it should start throttling. Previously this was tied to a given
> trip point as a cooling device and used the temperature specified for
> that trip point. This doesn't work well because the throttling mechanism
> is not a cooling device in the traditional sense.
>
> Instead, allow device trees to specify the throttle temperature in the
> throttle configuration directly so that the throttle doesn't need to be
> exposed as a cooling device.
>
> Signed-off-by: Thierry Reding <treding@nvidia.com>
> ---
> .../bindings/thermal/nvidia,tegra124-soctherm.yaml | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/thermal/nvidia,tegra124-soctherm.yaml b/Documentation/devicetree/bindings/thermal/nvidia,tegra124-soctherm.yaml
> index 4677ad6645a5..37dac851f486 100644
> --- a/Documentation/devicetree/bindings/thermal/nvidia,tegra124-soctherm.yaml
> +++ b/Documentation/devicetree/bindings/thermal/nvidia,tegra124-soctherm.yaml

File does not exist in next and no dependency is mentioned, so tricky to
review and figure out context. Without context the comment is:

> @@ -120,6 +120,13 @@ properties:
> # high (85%, TEGRA_SOCTHERM_THROT_LEVEL_HIGH)
> - 3
>
> + temperature:
> + $ref: /schemas/types.yaml#/definitions/int32

Use -millicelsius suffix instead:
https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/property-units.yaml

> + minimum: -273000
> + maximum: 200000
> + description: The temperature threshold (in millicelsius) that,
> + when crossed, will trigger the configured automatic throttling.

Don't you want some hysteresis? Or is it already using trips binding?
But in that case you should skip the $ref and maximum - they come from
thermal-zones, don't they?

Best regards,
Krzysztof