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
prev parent 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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).