All of lore.kernel.org
 help / color / mirror / Atom feed
From: Andy Lutomirski <luto@kernel.org>
To: Stefan Schaeckeler <schaecsn@gmx.net>
Cc: Wolfram Sang <wsa@the-dreams.de>,
	Andrew Lutomirski <luto@kernel.org>,
	linux-i2c@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
	Andy Shevchenko <andy.shevchenko@gmail.com>
Subject: Re: [PATCH 0/1] i2c: imc: Add support for Intel iMC SMBus host controller.
Date: Sun, 5 Apr 2020 15:51:29 -0700	[thread overview]
Message-ID: <CALCETrVUWEOwpMOLAPieU5mffaA6vJPWQov5N82gtcBo04JsyA@mail.gmail.com> (raw)
In-Reply-To: <20200405214059.91F97899799@corona.crabdance.com>

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

      reply	other threads:[~2020-04-05 22:51 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-23 22:51 [PATCH 0/1] i2c: imc: Add support for Intel iMC SMBus host controller Stefan Schaeckeler
2020-02-23 22:51 ` [PATCH 1/1] " Stefan Schaeckeler
2020-02-25  8:22 ` [PATCH 0/1] " Andy Shevchenko
2020-02-25 21:49 ` Andy Lutomirski
2020-03-01 19:02   ` Stefan Schaeckeler
2020-04-05 18:05   ` Wolfram Sang
2020-04-05 21:40     ` Stefan Schaeckeler
2020-04-05 22:51       ` Andy Lutomirski [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CALCETrVUWEOwpMOLAPieU5mffaA6vJPWQov5N82gtcBo04JsyA@mail.gmail.com \
    --to=luto@kernel.org \
    --cc=andy.shevchenko@gmail.com \
    --cc=linux-i2c@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=schaecsn@gmx.net \
    --cc=wsa@the-dreams.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.