[PATCH v1] imx: Fix critical thermal threshold

[Peng Fan]

> Subject: Re: [PATCH v1] imx: Fix critical thermal threshold
> 
> Hello Peng,
> 
> On Wed, Nov 13, 2024 at 05:27:23AM +0000, Peng Fan wrote:
> > > Subject: [PATCH v1] imx: Fix critical thermal threshold
> > >
> > > From: Francesco Dolcini <francesco.dolcini at toradex.com>
> > >
> > > Fix the critical thermal threshold for i.MX processors, this was
> > > changed while moving the code from imx8m/imx9 directories into
> a
> > > shared place.
> > >
> > > There is no need to keep the critical threshold 5 degrees less than
> > > the SoC maximum temperature threshold, what is actually going to
> > > happen in practice is that we are going to power-off the board
> when
> > > the SoC is still within its working temperature range.
> >
> > Should we leave some margin for the critical temperature?
> 
> What's the point of such a margin? For doing what?
> 
> What is happening is that the OS takes some drastic measure when the
> critical threshold is reached, for example rebooting or shutting down
> the system. Why would I want to deliberately remove 5 Celsius degrees
> of valid working temperature range from my SoC?

The maxc means the maximum temperature that the soc might run at.
If the current temperature >= maxc, the chip might be broken.
And temperature sensor may have some deviation.
So leave margin for SW to shutdown the system. 

Regards,
Peng.
> 
> Eventually, assuming such a use case would exist, it must be made
> configurable.
> The change you implemented is just creating a regression for existing
> users (this is the reason I noticed, it broke our device functionality).
> 
> Francesco