From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755576AbbAFOiZ (ORCPT ); Tue, 6 Jan 2015 09:38:25 -0500 Received: from foss-mx-na.foss.arm.com ([217.140.108.86]:55987 "EHLO foss-mx-na.foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755268AbbAFOiU (ORCPT ); Tue, 6 Jan 2015 09:38:20 -0500 From: "Charles Garcia-Tobin" To: "Catalin Marinas" , "Arnd Bergmann" Cc: , , "Mark Rutland" , , "Will Deacon" , "Lv Zheng" , "Rob Herring" , "Lorenzo Pieralisi" , "Al Stone" , "Daniel Lezcano" , "Robert Moore" , , , , "Robert Richter" , "Jason Cooper" , "Marc Zyngier" , "Liviu Dudau" , "Mark Brown" , "Bjorn Helgaas" , , , "Randy Dunlap" , "Rafael J. Wysocki" , , "Sudeep Holla" , "Olof Johansson" References: <1413553034-20956-1-git-send-email-hanjun.guo@linaro.org> <54ABC2CB.6@linaro.org> <20150106112929.GB8829@e104818-lin.cambridge.arm.com> <2647669.mQf6pODdjV@wuerfel> <20150106141630.GG8829@e104818-lin.cambridge.arm.com> In-Reply-To: <20150106141630.GG8829@e104818-lin.cambridge.arm.com> Subject: RE: [PATCH v5 18/18] Documentation: ACPI for ARM64 Date: Tue, 6 Jan 2015 14:37:58 -0000 Message-ID: <000d01d029be$5ff967d0$1fec3770$@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 14.0 Thread-Index: AdApu2dAQ/qk54t+R8WKJdX+vWVJcwAAg8kQ Content-Language: en-gb Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > -----Original Message----- > From: Catalin Marinas [mailto:catalin.marinas@arm.com] > Sent: 06 January 2015 14:17 > To: Arnd Bergmann > Cc: linux-arm-kernel@lists.infradead.org; hanjun.guo@linaro.org; Mark > Rutland; linaro-acpi@lists.linaro.org; Will Deacon; Lv Zheng; Rob > Herring; Lorenzo Pieralisi; Al Stone; Daniel Lezcano; Robert Moore; > linux-acpi@vger.kernel.org; jcm@redhat.com; grant.likely@linaro.org; > Charles Garcia-Tobin; Robert Richter; Jason Cooper; Marc Zyngier; Liviu > Dudau; Mark Brown; Bjorn Helgaas; graeme.gregory@linaro.org; > Kangkang.Shen@huawei.com; Randy Dunlap; Rafael J. Wysocki; linux- > kernel@vger.kernel.org; Sudeep Holla; Olof Johansson > Subject: Re: [PATCH v5 18/18] Documentation: ACPI for ARM64 > > On Tue, Jan 06, 2015 at 02:05:12PM +0000, Arnd Bergmann wrote: > > On Tuesday 06 January 2015 11:29:29 Catalin Marinas wrote: > > > > >> We will work on this both on ASWG and linux ACPI driver side, > as Dong > > > > >> and Charles pointed out, _OSI things can be solved in ACPI > spec, when > > > > >> that is done, we can modify the kernel driver to fix the > problems above. > > > > > > > > > > Which driver? > > > > > > > > the ACPICA core driver as you suggested, sorry for the confusion. > > > > > > > > > What about ACPI_OS_NAME? Would you suggest it is fine to report > > > > > "Microsoft Windows NT" on an ARM system? That _OS_ not _OSI. > > > > > > > > No, not at all. I prefer "Linux" > > > > In include/acpi/acconfig.h, when ACPI_OS_NAME defined, it says: > > > > "OS name, used for the _OS object. The _OS object is essentially > > > > obsolete,..." > > > > for some legacy reasons, we needed "Microsoft Windows NT", but > ACPI > > > > for ARM64 on linux is totally new, I think we can change it to > > > > "Linux" when CONFIG_ARM64 as you suggested. > > > > > > We could ignore this change for now if we don't expect the _OS > object to > > > be used at all. But do we have any other way to check the AML code > for > > > this? Would FWTS catch such obsolete cases? > > > > How about just leaving it out? It's clearly not used for anything > > good, so I don't see the point in passing either Linux or "Microsoft > > Windows NT" here. > > Do you mean defining it to NULL (so it ends up as NULL in > acpi_gbl_pre_defined_names) or removing "_OS_" entirely from that > array? > I really can't tell what the implications are. To me, given that we don't want to use it in ARM64, it would make sense to have some method to configurably: 0. Leave as is 1. Warn for usage 2. Panic With a configurability method that allows FWTS to make use of it, and therefore catch usages of the method. Cheers Charles > > -- > Catalin