Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755977AbaLIKCw (ORCPT ); Tue, 9 Dec 2014 05:02:52 -0500 Received: from foss-mx-na.foss.arm.com ([217.140.108.86]:46779 "EHLO foss-mx-na.foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755864AbaLIKCt (ORCPT ); Tue, 9 Dec 2014 05:02:49 -0500 Message-ID: <5486C8BA.8030608@arm.com> Date: Tue, 09 Dec 2014 10:02:34 +0000 From: Marc Zyngier User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.2.0 MIME-Version: 1.0 To: Yijing Wang , Bjorn Helgaas , Thomas Gleixner , Jiang Liu CC: "linux-arm-kernel@lists.infradead.org" , "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Will Deacon , "suravee.suthikulpanit@amd.com" Subject: Re: [PATCH 2/6] PCI/MSI: add hooks to populate the msi_domain field References: <1418069543-21969-1-git-send-email-marc.zyngier@arm.com> <1418069543-21969-3-git-send-email-marc.zyngier@arm.com> <5486585B.40000@huawei.com> In-Reply-To: <5486585B.40000@huawei.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Yijing, On 09/12/14 02:03, Yijing Wang wrote: > On 2014/12/9 4:12, Marc Zyngier wrote: >> In order to be able to populate the device msi_domain field, >> add the necesary hooks to propagate the PHB msi_domain across >> secondary busses to devices. >> >> So far, nobody populates the initial msi_domain. >> >> Signed-off-by: Marc Zyngier >> --- >> drivers/pci/probe.c | 24 ++++++++++++++++++++++++ >> include/linux/pci.h | 1 + >> 2 files changed, 25 insertions(+) >> >> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c >> index c8ca98c..d1009a2 100644 >> --- a/drivers/pci/probe.c >> +++ b/drivers/pci/probe.c >> @@ -670,6 +670,20 @@ static void pci_set_bus_speed(struct pci_bus *bus) >> } >> } >> >> +void __weak pcibios_set_phb_msi_domain(struct pci_bus *bus) >> +{ >> +} >> + >> +static void pci_set_bus_msi_domain(struct pci_bus *bus) >> +{ >> + struct pci_dev *bridge = bus->self; >> + >> + if (!bridge) >> + pcibios_set_phb_msi_domain(bus); >> + else >> + dev_set_msi_domain(&bus->dev, dev_get_msi_domain(&bridge->dev)); >> +} > > > Hi Marc, we can not assume pci devices under same phb share the same msi irq domain, > now in x86, pci devices under the same phb may associate different msi irq domain. Well, this is not supposed to be a perfect solution yet, but instead a basis for discussion. What I'd like to find out is: - What is the minimum granularity for associating a device with its MSI domain in existing platforms? - What topology data structures do you use to find out what MSI controller a device should be matched with? - What in-tree platform already has this requirements? Thanks, M. -- Jazz is not dead. It just smells funny... -- 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/