From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757102AbbFQPNA (ORCPT ); Wed, 17 Jun 2015 11:13:00 -0400 Received: from bh-25.webhostbox.net ([208.91.199.152]:37124 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753443AbbFQPM6 (ORCPT ); Wed, 17 Jun 2015 11:12:58 -0400 Date: Wed, 17 Jun 2015 08:12:51 -0700 From: Guenter Roeck To: Wolfram Sang Cc: Andy Lutomirski , Boaz Harrosh , One Thousand Gnomes , Rui Wang , Jean Delvare , Alun Evans , Robert Elliott , "linux-i2c@vger.kernel.org" , Mauro Carvalho Chehab , Paul Bolle , Tony Luck , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v2 1/2] i2c_imc: New driver for Intel's iMC, found on LGA2011 chips Message-ID: <20150617151251.GA1043@roeck-us.net> References: <86c8b4d72f76cfdb7f76ad48825fb10e51634429.1425934386.git.luto@amacapital.net> <5503B59B.2020502@roeck-us.net> <20150617131841.GI13393@katana> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150617131841.GI13393@katana> User-Agent: Mutt/1.5.23 (2014-03-12) X-Authenticated_sender: guenter@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: guenter@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 17, 2015 at 03:18:42PM +0200, Wolfram Sang wrote: > > > > Having said that, I am still not convinced that the driver should be in the kernel > > > to start with. Browsing through Intel's datasheets, the registers are supported > > > in E5-2600 v1, v2, and v3. However, in v3 Intel added a note saying that the registers > > > should not be accessed by the OS directly, but only through the bios. Given that, > > > and if that is possible, it might make more sense to rely on ACPI. It would then > > > be up to the board and/or BIOS vendor to decide if the information should be available > > > to the OS or not. > > > > I think the plan is to add something to ACPI to tell us when we can > > use these registers. Unfortunately I'm not privy to whatever the ACPI > > committee is doing. > > Coming from the embedded world and not knowing much about this, I tend > to wait until the above issue is clear, meaning when and how this driver > is safe to be used. I hope you don't mind. Keeping your code up to date > and sharing it is much appreciated, though! As well as Guenter's comments. > When I suggested that we should rely on ACPI, I meant through ACPI SMBus CMI (i2c-scmi), not through some ACPI properties which would permit direct access. Thanks, Guenter From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guenter Roeck Subject: Re: [PATCH v2 1/2] i2c_imc: New driver for Intel's iMC, found on LGA2011 chips Date: Wed, 17 Jun 2015 08:12:51 -0700 Message-ID: <20150617151251.GA1043@roeck-us.net> References: <86c8b4d72f76cfdb7f76ad48825fb10e51634429.1425934386.git.luto@amacapital.net> <5503B59B.2020502@roeck-us.net> <20150617131841.GI13393@katana> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20150617131841.GI13393@katana> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Wolfram Sang Cc: Andy Lutomirski , Boaz Harrosh , One Thousand Gnomes , Rui Wang , Jean Delvare , Alun Evans , Robert Elliott , "linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Mauro Carvalho Chehab , Paul Bolle , Tony Luck , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: linux-i2c@vger.kernel.org On Wed, Jun 17, 2015 at 03:18:42PM +0200, Wolfram Sang wrote: > > > > Having said that, I am still not convinced that the driver should be in the kernel > > > to start with. Browsing through Intel's datasheets, the registers are supported > > > in E5-2600 v1, v2, and v3. However, in v3 Intel added a note saying that the registers > > > should not be accessed by the OS directly, but only through the bios. Given that, > > > and if that is possible, it might make more sense to rely on ACPI. It would then > > > be up to the board and/or BIOS vendor to decide if the information should be available > > > to the OS or not. > > > > I think the plan is to add something to ACPI to tell us when we can > > use these registers. Unfortunately I'm not privy to whatever the ACPI > > committee is doing. > > Coming from the embedded world and not knowing much about this, I tend > to wait until the above issue is clear, meaning when and how this driver > is safe to be used. I hope you don't mind. Keeping your code up to date > and sharing it is much appreciated, though! As well as Guenter's comments. > When I suggested that we should rely on ACPI, I meant through ACPI SMBus CMI (i2c-scmi), not through some ACPI properties which would permit direct access. Thanks, Guenter