Re: [PATCH v3 4/7] thermal/drivers/tegra: Add driver for Tegra30 thermal sensor
From: Daniel Lezcano <hidden>
Date: 2021-06-15 10:03:38
Also in:
linux-devicetree, linux-pm, lkml
From: Daniel Lezcano <hidden>
Date: 2021-06-15 10:03:38
Also in:
linux-devicetree, linux-pm, lkml
[Cc Viresh] On 29/05/2021 19:09, Dmitry Osipenko wrote:
All NVIDIA Tegra30 SoCs have a two-channel on-chip sensor unit which monitors temperature and voltage of the SoC. Sensors control CPU frequency throttling, which is activated by hardware once preprogrammed temperature level is breached, they also send signal to Power Management controller to perform emergency shutdown on a critical overheat of the SoC die. Add driver for the Tegra30 TSENSOR module, exposing it as a thermal sensor and a cooling device.
IMO it does not make sense to expose the hardware throttling mechanism as a cooling device because it is not usable anywhere from the thermal framework. Moreover, that will collide with the thermal / cpufreq framework mitigation (hardware sets the frequency but the software thinks the freq is different), right ? The hardware limiter should let know the cpufreq framework about the frequency change. https://lkml.org/lkml/2021/6/8/1792 May be post the sensor without the hw limiter for now and address that in a separate series ? -- Daniel -- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog