From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from service87.mimecast.com ([91.220.42.44]:50817 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932947AbaJ3RjT convert rfc822-to-8bit (ORCPT ); Thu, 30 Oct 2014 13:39:19 -0400 Date: Thu, 30 Oct 2014 17:39:15 +0000 From: Liviu Dudau To: Jason Gunthorpe Cc: Lorenzo Pieralisi , "linux-arm-kernel@lists.infradead.org" , "linux-pci@vger.kernel.org" , Krzysztof Halasa , Arnd Bergmann , Phil Edworthy , Jingoo Han , Bjorn Helgaas , Russell King , Mohit Kumar Subject: Re: [RFC PATCH 0/2] arm: pcibios: remove pci_sys_data domain Message-ID: <20141030173914.GS1069@e106497-lin.cambridge.arm.com> References: <1414669490-1217-1-git-send-email-lorenzo.pieralisi@arm.com> <20141030162552.GC26820@obsidianresearch.com> <20141030165246.GC2048@red-moon> <20141030170305.GE26820@obsidianresearch.com> MIME-Version: 1.0 In-Reply-To: <20141030170305.GE26820@obsidianresearch.com> Content-Type: text/plain; charset=UTF-8 Sender: linux-pci-owner@vger.kernel.org List-ID: On Thu, Oct 30, 2014 at 05:03:05PM +0000, Jason Gunthorpe wrote: > On Thu, Oct 30, 2014 at 04:52:46PM +0000, Lorenzo Pieralisi wrote: > > On Thu, Oct 30, 2014 at 04:25:52PM +0000, Jason Gunthorpe wrote: > > > On Thu, Oct 30, 2014 at 11:44:46AM +0000, Lorenzo Pieralisi wrote: > > > > > > > Code in drivers/pci/pci-mvebu.c has been changed to add a domain > > > > number to PCI resources by using the nr value coming from the setup > > > > pcibios32 callback, which may not be correct and should be considered > > > > a temporary solution waiting for review comments. > > > > > > The intent of the string was to have the domain number so that > > > resources in /proc/iomem can be correlated with lspci. > > > > > > This would be a 'best practice' - all PCI drivers need to request > > > resource, and the resource should be relatable back to the PCI > > > domain... So it would be best if the domain number was available at > > > this point in a driver's flow. > > > > It is not available with the new approach and the generic PCI domains since > > the set-up hook is called before creating the pci_bus. That's why > > I mentioned that in the cover letter, and that's good it caught your > > attention. > > > > On a side note, when the resources are parsed from DT ranges, ie in: > > > > of_pci_get_host_bridge_resources() > > > > the resources won't contain the domain number you are looking for here, for > > the records, so we'd better find an agreement sooner rather than later. > > Well, it is very unfortunate that things are globally not sequenced to > allow proper resource names :( But of_pci_get_host_bridge_resources() does not request the resources, it only creates them out of the DT ranges. If/when the driver decides the list of resources is correct and it can work with it can also request them and use whatever domain number allocation strategy it wants (auto-incrementing or DT based). So I don't think the global sequencing is broken here. Best regards, Liviu > > But it also isn't really a big deal in the grand scheme of > things. Maybe it can be fixed later :| > > > So basically I could go as far as sticking 0000 to the string given the > > current code. I did not drop the 0x04x entirely since I do not want to break > > userspace, I was tempted though, let me know if I am allowed to do that. > > I'd just drop it entirely then, nobody is going to parse /proc/iomem > > Jason > -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯