From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423363AbcBQOH3 (ORCPT ); Wed, 17 Feb 2016 09:07:29 -0500 Received: from mail-wm0-f47.google.com ([74.125.82.47]:38729 "EHLO mail-wm0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1423147AbcBQOH0 (ORCPT ); Wed, 17 Feb 2016 09:07:26 -0500 Subject: Re: [PATCH V5 07/15] pci, acpi: Provide generic way to assign bus domain number. To: Jayachandran Chandrashekaran Nair References: <1455630825-27253-1-git-send-email-tn@semihalf.com> <1455630825-27253-8-git-send-email-tn@semihalf.com> Cc: Bjorn Helgaas , Arnd Bergmann , will.deacon@arm.com, catalin.marinas@arm.com, rafael@kernel.org, hanjun.guo@linaro.org, Lorenzo Pieralisi , okaya@codeaurora.org, jiang.liu@linux.intel.com, Jayachandran Chandrashekaran Nair , Stefano.Stabellini@eu.citrix.com, robert.richter@caviumnetworks.com, mw@semihalf.com, Liviu.Dudau@arm.com, ddaney@caviumnetworks.com, wangyijing@huawei.com, 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, jcm@redhat.com From: Tomasz Nowicki Message-ID: <56C47E9A.5010901@semihalf.com> Date: Wed, 17 Feb 2016 15:07:22 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Firefox/38.0 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 17.02.2016 14:44, Jayachandran Chandrashekaran Nair wrote: > Tomasz, Lorenzo, > > On Tue, Feb 16, 2016 at 7:23 PM, Tomasz Nowicki wrote: >> >As we now have valid PCI host bridge device reference we can >> >introduce code that is going to find its bus domain number using >> >ACPI _SEG method. >> > >> >Note that _SEG method is optional, therefore _SEG absence means >> >that all PCI buses belong to domain 0. >> > >> >While at it, for the sake of code clarity we put ACPI and DT domain >> >assign methods into the corresponding helpers. > In my patchset, I had a slightly different and I think better approach for > this without calling the _SEG method again. Please see > http://www.spinics.net/lists/arm-kernel/msg478167.html > at the last part ofhttp://www.spinics.net/lists/arm-kernel/msg478169.html Relying on NULL parent device to make decision on boot method is really ugly way. This may hit us again once we want to obtain another firmware specific info e.g. numa node. IMO we need to fix it this way. Tomasz