Re: [PATCH v5 6/6] arm64: dts: qcom: Enable cpu cooling devices for QCS9075 platforms

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 29.12.2024 4:23 PM, Wasim Nazir wrote:
> From: Manaf Meethalavalappu Pallikunhi <quic_manafm@quicinc.com>
> 
> In QCS9100 SoC, the safety subsystem monitors all thermal sensors and
> does corrective action for each subsystem based on sensor violation
> to comply safety standards. But as QCS9075 is non-safe SoC it
> requires conventional thermal mitigation to control thermal for
> different subsystems.
> 
> The cpu frequency throttling for different cpu tsens is enabled in
> hardware as first defense for cpu thermal control. But QCS9075 SoC
> has higher ambient specification. During high ambient condition, even
> lowest frequency with multi cores can slowly build heat over the time
> and it can lead to thermal run-away situations. This patch restrict
> cpu cores during this scenario helps further thermal control and
> avoids thermal critical violation.
> 
> Add cpu idle injection cooling bindings for cpu tsens thermal zones
> as a mitigation for cpu subsystem prior to thermal shutdown.
> 
> Add cpu frequency cooling devices that will be used by userspace
> thermal governor to mitigate skin thermal management.
> 
> Signed-off-by: Manaf Meethalavalappu Pallikunhi <quic_manafm@quicinc.com>
> ---

Does this bring measurable benefits over just making the CPU a cooling
device and pointing the thermal zones to it (and not the idle subnode)?

Konrad