Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752681AbbLUXM5 (ORCPT ); Mon, 21 Dec 2015 18:12:57 -0500 Received: from mx5-phx2.redhat.com ([209.132.183.37]:39831 "EHLO mx5-phx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752589AbbLUXMz convert rfc822-to-8bit (ORCPT ); Mon, 21 Dec 2015 18:12:55 -0500 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8BIT From: Jon Masters MIME-Version: 1.0 Subject: Re: [PATCH V2 22/23] pci, acpi: Match PCI config space accessors against platfrom specific quirks. Message-Id: <335CDE2E-B588-43A8-8665-6023AFD0EA04@redhat.com> Date: Mon, 21 Dec 2015 18:10:58 -0500 (EST) References: <1450278993-12664-1-git-send-email-tn@semihalf.com> <1450278993-12664-23-git-send-email-tn@semihalf.com> <201512211510.32029.arnd@arndb.de> To: Arnd Bergmann In-Reply-To: <201512211510.32029.arnd@arndb.de> Cc: Gabriele Paoloni , Tomasz Nowicki , "bhelgaas@google.com" , "will.deacon@arm.com" , "catalin.marinas@arm.com" , "rjw@rjwysocki.net" , "hanjun.guo@linaro.org" , "Lorenzo.Pieralisi@arm.com" , "okaya@codeaurora.org" , "jiang.liu@linux.intel.com" , "Stefano.Stabellini@eu.citrix.com" , "robert.richter@caviumnetworks.com" , "mw@semihalf.com" , "Liviu.Dudau@arm.com" , "ddaney@caviumnetworks.com" , "tglx@linutronix.de" , Wangyijing , "Suravee.Suthikulpanit@amd.com" , "msalter@redhat.com" , "linux-pci@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-acpi@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linaro-acpi@lists.linaro.org" , "jchandra@broadcom.com" X-Mailer: Zimbra 8.0.6_GA_5922 (MobileSync - Apple-iPhone7C1/1303.75) Thread-Topic: pci, acpi: Match PCI config space accessors against platfrom specific quirks. Thread-Index: C4h9wYLoK3yOkaf1kTjTrXEjuV/yng== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1950 Lines: 40 Sorry for top-posting. A quick note that SMBIOS3 is required by SBBR so it can be presumed that compliant platforms will provide quirks via DMI. -- Computer Architect | Sent from my 64-bit #ARM Powered phone > On Dec 21, 2015, at 09:11, Arnd Bergmann wrote: > > On Monday 21 December 2015, Gabriele Paoloni wrote: >>> -----Original Message----- >>> From: linux-kernel-owner@vger.kernel.org [mailto:linux-kernel- >>> owner@vger.kernel.org] On Behalf Of Tomasz Nowicki > >>> Some platforms may not be fully compliant with generic set of PCI >>> config accessors. For these cases we implement the way to overwrite >>> accessors set before PCI buses enumeration. Algorithm that overwrite >>> accessors matches against platform ID (DMI), domain and bus number, >>> hopefully enough for all cases. All quirks can be defined using: >>> DECLARE_ACPI_MCFG_FIXUP() and keep self contained. >> >> I've got a couple of comments/questions about this patch.. >> >> 1) So according to this mechanism quirks would be supported only by >> vendors whose BIOS are SMBIOS compliant. Now personally I am ok >> with this but I don't know if this is OK in general as it would >> narrow down the number of platforms that would be able to define >> the quirks... >> Lorenzo, Arnd what is your opinion here? > > I'd rather not see the quirks in mainline at all, and only support > SBSA compliant machines, or require the BIOS to work around the hardware > quirks differently (e.g. by trapping config space access through secure > firmware, or going through an AML method to be defined). I'm certainly > ok with making it depend on SMBIOS if we are going to use something like this. > > Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/