linux-kernel - Re: [PATCH v7 3/3] arm64: dts: imx91: Add thermal-sensor and thermal-zone support

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] [day] [month] [year] [list]

Message-ID: <aPi4VqxIF/hltDC5@alb3rt0-ThinkPad-P15-Gen-1>
Date: Wed, 22 Oct 2025 12:56:22 +0200
From: Alberto Merciai <alb3rt0.m3rciai@...il.com>
To: Frank Li <Frank.Li@....com>
Cc: "Rafael J. Wysocki" <rafael@...nel.org>,
	Daniel Lezcano <daniel.lezcano@...aro.org>,
	Zhang Rui <rui.zhang@...el.com>, Lukasz Luba <lukasz.luba@....com>,
	Rob Herring <robh@...nel.org>,
	Krzysztof Kozlowski <krzk+dt@...nel.org>,
	Conor Dooley <conor+dt@...nel.org>, Shawn Guo <shawnguo@...nel.org>,
	Sascha Hauer <s.hauer@...gutronix.de>,
	Pengutronix Kernel Team <kernel@...gutronix.de>,
	Fabio Estevam <festevam@...il.com>,
	Pengfei Li <pengfei.li_1@....com>,
	Marco Felsch <m.felsch@...gutronix.de>, linux-pm@...r.kernel.org,
	devicetree@...r.kernel.org, imx@...ts.linux.dev,
	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
	ye.li@....com, joy.zou@....com
Subject: Re: [PATCH v7 3/3] arm64: dts: imx91: Add thermal-sensor and
 thermal-zone support

On Mon, Oct 20, 2025 at 03:00:42PM -0400, Frank Li wrote:
> Add thermal-sensor and thermal-zone support.
> 
> Signed-off-by: Frank Li <Frank.Li@....com>
> ---
> changes in v7
> - new patch
> ---
>  arch/arm64/boot/dts/freescale/imx91.dtsi | 58 ++++++++++++++++++++++++++++++++
>  1 file changed, 58 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/freescale/imx91.dtsi b/arch/arm64/boot/dts/freescale/imx91.dtsi
> index 4d8300b2a7bca33bd0613db9e79d2fba6b40c052..f075592bfc01f1eb94d2a2bd8eea907cc2aed090 100644
> --- a/arch/arm64/boot/dts/freescale/imx91.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx91.dtsi
> @@ -6,6 +6,54 @@
>  #include "imx91-pinfunc.h"
>  #include "imx91_93_common.dtsi"
>  
> +/{
> +	thermal-zones {
> +		cpu-thermal {
> +			polling-delay-passive = <250>;
> +			polling-delay = <2000>;
> +			thermal-sensors = <&tmu 0>;
> +
> +			trips {
> +				cpu_alert: cpu-alert {
> +					temperature = <80000>;
> +					hysteresis = <2000>;
> +					type = "passive";
> +				};
> +
> +				cpu_crit: cpu-crit {
> +					temperature = <90000>;
> +					hysteresis = <2000>;
> +					type = "critical";
> +				};
> +			};
> +
> +			cooling-maps {
> +				map0 {
> +					trip = <&cpu_alert>;
> +					cooling-device =
> +						<&A55_0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> +				};
> +			};
> +		};
> +	};
> +};

Here you define cooling-maps with passive and critical trip points. 

I was trying test that by enabling CONFIG_THERMAL_EMULATION and setting
the emulated temp via 

echo 85000 > /sys/class/thermal/thermal_zone0/emul_temp

By checking with mhz (from lmbench Yocto recipe) command I was expecting that the 91 start
throttling but is not the case, Am I missing something?

Thanks,
Alberto