Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934493AbaDIXu7 (ORCPT ); Wed, 9 Apr 2014 19:50:59 -0400 Received: from gate.crashing.org ([63.228.1.57]:44507 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933495AbaDIXu4 (ORCPT ); Wed, 9 Apr 2014 19:50:56 -0400 Message-ID: <1397087391.3671.153.camel@pasglop> Subject: Re: [PATCH v7 4/6] pci: Introduce a domain number for pci_host_bridge. From: Benjamin Herrenschmidt To: Bjorn Helgaas Cc: linux-pci , Catalin Marinas , Will Deacon , linaro-kernel , Arnd Bergmann , LKML , "devicetree@vger.kernel.org" , LAKML , Tanmay Inamdar , Grant Likely Date: Thu, 10 Apr 2014 09:49:51 +1000 In-Reply-To: References: <1394811272-1547-1-git-send-email-Liviu.Dudau@arm.com> <1394811272-1547-5-git-send-email-Liviu.Dudau@arm.com> <20140405000007.GD15806@google.com> <20140407084623.GG17163@e106497-lin.cambridge.arm.com> <1396862058.3671.40.camel@pasglop> <20140407100715.GI17163@e106497-lin.cambridge.arm.com> <20140408102043.GV17163@e106497-lin.cambridge.arm.com> <20140409120750.GN985@e106497-lin.cambridge.arm.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.11.90 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2014-04-09 at 08:02 -0600, Bjorn Helgaas wrote: > It's possible we could manage domain numbers in the core. On ACPI > systems, we currently we use the ACPI _SEG value as the domain. In > some cases, e.g., on ia64, config space access is done via firmware > interfaces, and those interfaces expect the _SEG values. We could > conceivably maintain a mapping between _SEG and domain, but I'm not > sure there's an advantage there. I'd rather keep the ability for the architecture to assign domain numbers. I'm working on making them relate to the physical slot numbers on our new systems so we get predictable PCI IDs which helps with some stuff like the new network device naming scheme etc... Predictability is a good thing :-) > I probably don't understand what you intend by reversing the order. > Are you suggesting something like new pcibios_*() interfaces the arch > can use to get the host bridge apertures and domain number? Cheers, Ben. -- 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/