Re: [PATCH 3/3] thermal: qcom: tsens: Implement re-initialization workaround quirk

[bhupesh.sharma@linaro.org]

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 ?

Regards,
Bhupesh