From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from szxga03-in.huawei.com ([119.145.14.66]:18114 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751000AbbAMMeL (ORCPT ); Tue, 13 Jan 2015 07:34:11 -0500 Message-ID: <54B510BA.7030202@huawei.com> Date: Tue, 13 Jan 2015 20:34:02 +0800 From: Yijing Wang MIME-Version: 1.0 To: Marc Zyngier , Bjorn Helgaas , Thomas Gleixner , Jiang Liu CC: , , , Suravee Suthikulpanit Subject: Re: [PATCH v2 2/8] PCI/MSI: Add hooks to populate the msi_domain field References: <1420736772-11088-1-git-send-email-marc.zyngier@arm.com> <1420736772-11088-3-git-send-email-marc.zyngier@arm.com> In-Reply-To: <1420736772-11088-3-git-send-email-marc.zyngier@arm.com> Content-Type: text/plain; charset="UTF-8" Sender: linux-pci-owner@vger.kernel.org List-ID: > static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent, > struct pci_dev *bridge, int busnr) > { > @@ -713,6 +727,7 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent, > bridge->subordinate = child; > > add_dev: > + pci_set_bus_msi_domain(child); > ret = device_register(&child->dev); > WARN_ON(ret < 0); > > @@ -1507,6 +1522,17 @@ static void pci_init_capabilities(struct pci_dev *dev) > pci_enable_acs(dev); > } > > +static void pci_set_msi_domain(struct pci_dev *dev) > +{ > + /* > + * If no domain has been set through the pcibios callback, > + * inherit the default from the bus device. > + */ > + if (!dev_get_msi_domain(&dev->dev)) > + dev_set_msi_domain(&dev->dev, > + dev_get_msi_domain(&dev->bus->dev)); > +} Hi Marc, now we have two ways to associate the pci_dev and msi_domain, right ? 1. associate pci_dev and msi_domain in pcibios_add_device() like x86. 2. Inherit msi_domain from pci_dev->bus. My question is if all pci devices inherit msi_domain from the pci_bus, so all pci devices under same pci host bridge have the same msi_domain assigned by weak pcibios_set_phb_msi_domain(). So why not save the pci host bridge specific msi_domain in pci_host_bridge. Then pci devices could inherit the msi_domain from its pci host bridge directly, no need to involve pci bus in the assignment. If I misunderstood, please let me know, :) Thanks! Yijing. > + > void pci_device_add(struct pci_dev *dev, struct pci_bus *bus) > { > int ret; > @@ -1547,6 +1573,9 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus) > ret = pcibios_add_device(dev); > WARN_ON(ret < 0); > > + /* Setup MSI irq domain */ > + pci_set_msi_domain(dev); > + > /* Notifier could use PCI capabilities */ > dev->match_driver = false; > ret = device_add(&dev->dev); > @@ -1937,6 +1966,7 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, > b->bridge = get_device(&bridge->dev); > device_enable_async_suspend(b->bridge); > pci_set_bus_of_node(b); > + pci_set_bus_msi_domain(b); > > if (!parent) > set_dev_node(b->bridge, pcibus_to_node(b)); > diff --git a/include/linux/pci.h b/include/linux/pci.h > index 360a966..13c65ab 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -1640,6 +1640,7 @@ int pcibios_set_pcie_reset_state(struct pci_dev *dev, > int pcibios_add_device(struct pci_dev *dev); > void pcibios_release_device(struct pci_dev *dev); > void pcibios_penalize_isa_irq(int irq, int active); > +void pcibios_set_phb_msi_domain(struct pci_bus *bus); > > #ifdef CONFIG_HIBERNATE_CALLBACKS > extern struct dev_pm_ops pcibios_pm_ops; > -- Thanks! Yijing