lkml.org 
[lkml]   [2020]   [Apr]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH 0/1] i2c: imc: Add support for Intel iMC SMBus host controller.
On Sun, Apr 5, 2020 at 2:41 PM Stefan Schaeckeler <schaecsn@gmx.net> wrote:
>
> 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

I think it could make sense to upstream this driver but to require a
scary boot-time option to enable it. Maybe i2c_imc.dangerous=1?

>
> Stefan

\
 
 \ /
  Last update: 2020-04-06 00:52    [W:0.044 / U:0.176 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site