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Subject: Re: [PATCH v6 0/6] Introduce Power domain based warming device driver
To:     Pavel Machek <pavel@ucw.cz>
Cc:     rui.zhang@intel.com, ulf.hansson@linaro.org,
        daniel.lezcano@linaro.org, bjorn.andersson@linaro.org,
        agross@kernel.org, robh@kernel.org, amit.kucheria@verdurent.com,
        mark.rutland@arm.com, rjw@rjwysocki.net, linux-pm@vger.kernel.org,
        devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20200604015317.31389-1-thara.gopinath@linaro.org>
 <20200616105325.GH1718@bug>
From:   Thara Gopinath <thara.gopinath@linaro.org>
Message-ID: <0eb2e140-9c9c-4777-9916-d81eddc793ca@linaro.org>
Date:   Tue, 16 Jun 2020 13:24:16 -0400
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On 6/16/20 6:53 AM, Pavel Machek wrote:
> Hi!
> 
>> Certain resources modeled as a generic power domain in linux kernel can be
>> used to warm up the SoC (mx power domain on sdm845) if the temperature
>> falls below certain threshold. These power domains can be considered as
>> thermal warming devices.  (opposite of thermal cooling devices).
> 
> Would you explain when this is needed?
> 
> I'd normally expect "too low" temperature to be a problem during power-on, but at
> that time Linux is not running so it can not provide the heating...
Hi Pavel,

This is more in the scenario if the system in on and temperature is 
dipping (I have been told in colder climates). Idea is to turn on 
resources so as to prevent further dipping of temperature if possible.

> 
> Best regards,
> 
> 									Pavel
> 

-- 
Warm Regards
Thara