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Message-ID: <d5dd721e-b0d7-f76d-d40c-b4927c236460@somainline.org>
Date:   Tue, 19 Jul 2022 12:39:35 +0200
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Subject: Re: [PATCH 3/3] thermal: qcom: tsens: Implement re-initialization
 workaround quirk
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To:     bhupesh.sharma@linaro.org, linux-pm@vger.kernel.org,
        bhupesh.linux@gmail.com, linux-kernel@vger.kernel.org,
        bjorn.andersson@linaro.org, Amit Kucheria <amitk@kernel.org>,
        Thara Gopinath <thara.gopinath@gmail.com>,
        linux-arm-msm@vger.kernel.org
References: <20220701145815.2037993-1-bhupesh.sharma@linaro.org>
 <20220701145815.2037993-4-bhupesh.sharma@linaro.org>
 <09ff7e3a-7dd5-db35-3795-89151afb5363@somainline.org>
 <e69cb444-2bee-870e-08ca-bbe3237d8166@linaro.org>
From:   Konrad Dybcio <konrad.dybcio@somainline.org>
In-Reply-To: <e69cb444-2bee-870e-08ca-bbe3237d8166@linaro.org>
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On 18.07.2022 08:34, bhupesh.sharma@linaro.org wrote:
> Hi Konrad,
> 
> On 7/15/22 8:26 PM, Konrad Dybcio <konrad.dybcio@somainline.org> wrote:
>>
>>
>> On 1.07.2022 16:58, Bhupesh Sharma wrote:
>> > Since for some QCoM tsens controllers, its suggested to
>> > monitor the controller health periodically and in case an
>> > issue is detected, to re-initialize the tsens controller
>> > via trustzone, add the support for the same in the
>> > qcom tsens driver.
>> >
>> > Note that Once the tsens controller is reset using scm call,
>> > all SROT and TM region registers will enter the reset mode.
>> >
>> > While all the SROT registers will be re-programmed and
>> > re-enabled in trustzone prior to the scm call exit, the TM
>> > region registers will not re-initialized in trustzone and thus
>> > need to be handled by the tsens driver.
>> >
>> > Cc: Amit Kucheria <amitk@kernel.org>
>> > Cc: Thara Gopinath <thara.gopinath@gmail.com>
>> > Cc: linux-pm@vger.kernel.org
>> > Cc: linux-arm-msm@vger.kernel.org
>> > Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
>> > Reported-by: kernel test robot <lkp@intel.com>
>> > ---
>> Hi, I think this should be also checked and applied on init. This
>> seems required for at least SM6375, as the controller starts (or
>> well, doesn't start...) in an unknown state and the driver does
>> not like it, as the TSENS_EN indicates it is disabled.
>> Downstream runs this right at probe..
> 
> Hmm.. very interesting. I was not aware of the SM6375 case, as for SM8150
> the controller starts in a valid state but may require reinit during operation.
> 
> So, I did not use the downstream approach to do it right at _probe() and then
> later while get_temp() is called.
> 
> Let me add that in v2. BTW do you want me to set the need_reinit_wa as true
> for SM6375 as well, or would you like to add that with a followup-patch ?
Please set it, I'll happily test it!

Konrad
> 
> Regards,
> Bhupesh