Re: [PATCH 0/1] i2c: imc: Add support for Intel iMC SMBus host controller.

[Stefan Schaeckeler]

Hello Wolfram,

> > > This patch is based on Andy Lutomirski's iMC SMBus driver patch-set
> > > https://lkml.org/lkml/2016/4/28/926. It never made it into the kernel. I hope
> > > this rewrite will:
> > >
> > >
> > > Overview
> > >
> > > Modern Intel memory controllers host an SMBus controller and connection to
> > > DIMMs and their thermal sensors. The memory controller firmware has three modes
> > > of operation: Closed Loop Thermal Throttling (CLTT), Open Loop Thermal
> > > Throttling (OLTT) and none.
> > >
> > > - CLTT: The memory controller firmware is periodically accessing the DIMM
> > >   temperature sensor over the SMBus.
> > >
> >
> >
> > I think this is great!  One question, though: what happens if the
> > system is in CLTT mode but you disable CLTT and claim the bus for too
> > long?  For example, if there's an infinite loop or other lockup which
> > you have the tsod polling interval set to 0?  Does the system catch
> > fire or does the system do something intelligent like temporarily
> > switching to open loop?
>
> Any news on this question?

Thank you for your interest in this patch. You can read my reply here
https://lkml.org/lkml/2020/3/1/216

 Stefan