Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756718AbaDPVVW (ORCPT ); Wed, 16 Apr 2014 17:21:22 -0400 Received: from quartz.orcorp.ca ([184.70.90.242]:60955 "EHLO quartz.orcorp.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753049AbaDPVVU (ORCPT ); Wed, 16 Apr 2014 17:21:20 -0400 Date: Wed, 16 Apr 2014 15:21:04 -0600 From: Jason Gunthorpe To: Rob Herring , Tanmay Inamdar , Bjorn Helgaas , Arnd Bergmann , Grant Likely , Rob Herring , Catalin Marinas , Rob Landley , Liviu Dudau , "linux-pci@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-doc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "patches@apm.com" , "jcm@redhat.com" Subject: Re: [PATCH v5 2/4] arm64: dts: APM X-Gene PCIe device tree nodes Message-ID: <20140416212104.GA3469@obsidianresearch.com> References: <1395270762-6055-1-git-send-email-tinamdar@apm.com> <1395270762-6055-3-git-send-email-tinamdar@apm.com> <20140416170545.GD4858@bart> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140416170545.GD4858@bart> User-Agent: Mutt/1.5.21 (2010-09-15) X-Broken-Reverse-DNS: no host name found for IP address 10.0.0.161 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 16, 2014 at 06:05:45PM +0100, Liviu Dudau wrote: > I have found out that we cannot pasd the config ranges from the DT into the > pci_host_bridge structure as the PCI framework doesn't have a resource type > for config resources. Leaving the translation between range flags and > resource type as is (filtered through the IORESOURCE_TYPE_BITS) will lead > to a resource type of value zero, which is not recognised by any resource > handling API so bridge configuration and bus scanning will barf. > > I'm looking for suggestions here, as Jason Gunthorpe suggested that we > should be able to parse config ranges if they conform to the ECAM part > of the PCI standard. The thinking here is the ranges should be well defined and general, it isn't a dumping ground for driver specific stuff. No spec says you can put config space into the ranges at all, nobody should be doing that today, obviously some cases were missed during review.. The comment about ECAM was intended as a general guidance on what config space in ranges could/should be used for. Right now config space shouldn't propagate out side any driver, so you can probably just filter it in your generic code, and make it very hard and obviously wrong for a driver to parse ranges for config space, so we don't get more usages. Jason -- 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/