Re: [PATCH 09/10] arm64: tegra: Rework SOCTHERM on Tegra132 and Tegra210

[Daniel Lezcano <daniel.lezcano@linaro.org>]

On 14/04/2023 14:57, Thierry Reding wrote:
> From: Thierry Reding <treding@nvidia.com>
> 
> The "heavy throttle" cooling device that SOCTHERM uses isn't a cooling
> device in the traditional sense. It's an automatic mechanism that cannot
> be actively controlled. Do not expose it as a cooling device and instead
> of tying it to a specific trip point, hard-code the temperature at which
> the automatic throttling will begin.
> 
> While at it, clean up the trip point names to reflect the names used by
> the thermal device tree bindings.
> 
> Signed-off-by: Thierry Reding <treding@nvidia.com>
> ---
>   arch/arm64/boot/dts/nvidia/tegra132.dtsi | 63 +++++-------------
>   arch/arm64/boot/dts/nvidia/tegra210.dtsi | 83 +++++++-----------------
>   2 files changed, 39 insertions(+), 107 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/nvidia/tegra132.dtsi b/arch/arm64/boot/dts/nvidia/tegra132.dtsi
> index 8b78be8f4f9d..11ebf7517df1 100644
> --- a/arch/arm64/boot/dts/nvidia/tegra132.dtsi
> +++ b/arch/arm64/boot/dts/nvidia/tegra132.dtsi
> @@ -876,11 +876,10 @@ soctherm: thermal-sensor@700e2000 {
>   		#thermal-sensor-cells = <1>;
>   
>   		throttle-cfgs {
> -			throttle_heavy: heavy {
> +			heavy {
>   				nvidia,priority = <100>;
>   				nvidia,cpu-throt-level = <TEGRA_SOCTHERM_THROT_LEVEL_HIGH>;
> -
> -				#cooling-cells = <2>;
> +				temperature = <102000>;
>   			};
>   		};
>   	};
> @@ -1136,114 +1135,84 @@ cpu-thermal {
>   			polling-delay-passive = <1000>;
>   			polling-delay = <0>;
>   
> -			thermal-sensors =
> -				<&soctherm TEGRA124_SOCTHERM_SENSOR_CPU>;
> +			thermal-sensors = <&soctherm TEGRA124_SOCTHERM_SENSOR_CPU>;
>   
>   			trips {
> -				cpu_shutdown_trip {
> +				critical {
>   					temperature = <105000>;
>   					hysteresis = <1000>;
>   					type = "critical";
>   				};
>   
> -				cpu_throttle_trip: throttle-trip {
> +				hot {
>   					temperature = <102000>;
>   					hysteresis = <1000>;
>   					type = "hot";
>   				};
>   			};
> -
> -			cooling-maps {
> -				map0 {
> -					trip = <&cpu_throttle_trip>;
> -					cooling-device = <&throttle_heavy 1 1>;
> -				};
> -			};

If the hardware mitigation is 'heavy', don't you want to have DVFS 
acting before hardware throttling ?

[ ... ]

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