From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752358AbbASKyu (ORCPT ); Mon, 19 Jan 2015 05:54:50 -0500 Received: from szxga02-in.huawei.com ([119.145.14.65]:47983 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752240AbbASKys (ORCPT ); Mon, 19 Jan 2015 05:54:48 -0500 Message-ID: <54BCE228.2020907@huawei.com> Date: Mon, 19 Jan 2015 18:53:28 +0800 From: Yijing Wang User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.0.1 MIME-Version: 1.0 To: Arnd Bergmann , CC: Liviu Dudau , Tony Luck , "Russell King" , Marc Zyngier , , , , "David S. Miller" , , Geert Uytterhoeven , , Bjorn Helgaas , , Thomas Gleixner , "Guan Xuetao" , Yinghai Lu , Jiang Liu Subject: Re: [PATCH 18/28] PCI/sparc: Use pci_scan_root_bridge() for simplicity References: <1421372666-12288-1-git-send-email-wangyijing@huawei.com> <2658988.B0VmbMPdJ9@wuerfel> <54BC772E.6020103@huawei.com> <7748275.Tf0dzsPZdA@wuerfel> In-Reply-To: <7748275.Tf0dzsPZdA@wuerfel> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.27.212] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2015/1/19 16:44, Arnd Bergmann wrote: > On Monday 19 January 2015 11:17:02 Yijing Wang wrote: >> On 2015/1/16 18:01, Arnd Bergmann wrote: >>> On Friday 16 January 2015 09:44:16 Yijing Wang wrote: >>>> +static void pci_host_bridge_probe_mode( >>>> + struct pci_host_bridge *host) >>>> +{ >>>> + host->of_scan = true; >>>> +} >>>> >>> >>> I probably missed something here, but where does host->of_scan >>> get used? >>> >> >> It is used in __pci_scan_root_bus() to detect whether of scan bus is needed in patch 11. > > Ok, I see it now. > >> @@ -2051,10 +2053,17 @@ static struct pci_bus *__pci_scan_root_bus( >> pci_bus_insert_busn_res(b, host->busnum, 255); >> } >> >> - max = pci_scan_child_bus(b); >> + if (host->ops && host->ops->phb_probe_mode) >> + host->ops->phb_probe_mode(host); >> >> - if (!found) >> - pci_bus_update_busn_res_end(b, max); >> + if (host->of_scan) { >> + if (host->ops &&host->ops->phb_of_scan_bus) >> + host->ops->phb_of_scan_bus(host); >> + } else { >> + max = pci_scan_child_bus(b); >> + if (!found) >> + pci_bus_update_busn_res_end(b, max); >> + } >> > > I think we can simplify this based on the knowledge that this code > will remain powerpc specific. How about removing the phb_probe_mode() > callback and replacing it with just a phb_scan_bus() callback that > will always get set on sparc, and do this on powerpc: > > +static void pci_host_bridge_of_scan_bus(struct pci_host_bridge *host) > +{ > + int mode = PCI_PROBE_NORMAL; > + struct pci_bus *bus = host->bus; > + struct pci_controller *hose = dev_get_drvdata(&host->dev); > + > + /* Get probe mode and perform scan */ > + if (hose->dn && ppc_md.pci_probe_mode) > + mode = ppc_md.pci_probe_mode(bus); > + > + pr_debug(" probe mode: %d\n", mode); > + if (mode == PCI_PROBE_DEVTREE) { > + of_scan_bus(host->dn, bus); > + return max; // XXX need to get this from somewhere > + } > + return pci_scan_child_bus(b); > +} > > Would that work? This looks good to me, it is more simple. Thanks! Yijing. > Arnd > > . > -- Thanks! Yijing