From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C8C3EC4BA01 for ; Tue, 25 Feb 2020 21:49:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 94C8320675 for ; Tue, 25 Feb 2020 21:49:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582667392; bh=HpOrLqgis/0esfG7dq2+OsTjc76h9zTqkjIJyDQmoKA=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=bvv0twlE1sdfiWlUxciFBMKVchmb2qGo9f32vME9kQEVHMnIVBiecQgvvO1HWvdXU xrP1PB4SZbGHS0Y89oNcWLdaT64NpBHYoKsyaGq3zMqvy0Kk3pOcTLlevZFX1AGmzx 4MWDxd9tiQRfUcd+IHXbqBqKG9eStvDRxA6n6i6c= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730014AbgBYVtv (ORCPT ); Tue, 25 Feb 2020 16:49:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:41228 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728162AbgBYVts (ORCPT ); Tue, 25 Feb 2020 16:49:48 -0500 Received: from mail-wr1-f48.google.com (mail-wr1-f48.google.com [209.85.221.48]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 879F721D7E for ; Tue, 25 Feb 2020 21:49:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582667387; bh=HpOrLqgis/0esfG7dq2+OsTjc76h9zTqkjIJyDQmoKA=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=gLhc7oCBf/dMrtwgyWAQsXlJBnnS8uxHJFBQTNslU/xlcEZ2XsI37rPDayexTl/na fUuMHI7ecFZvcl+kv3tj8ZSXWPVED6uI/6HeAmY/iraqGp56FGYmhadN6drQ3kLQ+1 Og4aSYroBhGJzgODXVENKVdfI5ISKrI2XKCmFvP0= Received: by mail-wr1-f48.google.com with SMTP id t3so477839wru.7 for ; Tue, 25 Feb 2020 13:49:47 -0800 (PST) X-Gm-Message-State: APjAAAWF/Zu9rmzg/aQe37e4c16Zu7g4QsGkBMMmAbOfIDvQAmgGutSF fUstQoVFYRyf85rRERTCoqGrHEdTXSZZksQEZaJi/g== X-Google-Smtp-Source: APXvYqwwlguw+9143UoHvRORjuDhvyP7pINZdcLc2/GmTaDHWw6AbKjBqD07WA/Fx7HmxjDN7uHVGZJ80tlj+nocYZ4= X-Received: by 2002:adf:df0c:: with SMTP id y12mr1116539wrl.257.1582667386041; Tue, 25 Feb 2020 13:49:46 -0800 (PST) MIME-Version: 1.0 References: <1582498270-50674-1-git-send-email-schaecsn@gmx.net> In-Reply-To: <1582498270-50674-1-git-send-email-schaecsn@gmx.net> From: Andy Lutomirski Date: Tue, 25 Feb 2020 13:49:34 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 0/1] i2c: imc: Add support for Intel iMC SMBus host controller. To: Stefan Schaeckeler Cc: linux-i2c@vger.kernel.org, LKML , Andy Lutomirski Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Feb 23, 2020 at 2:52 PM Stefan Schaeckeler wrote: > > 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?