Currently, after pci_create_bus(), resources available on the bus could be handled by pci_scan_child_bus(). The problem is that, in pci_scan_child_bus(), before calling arch-dependent pcibios_fixup_bus(), PCI quirks will probably conflict (while doing pci_claim_resource()) with resources like system controller's I/O resource that have not yet been added to the bus. One can see that, by default, ioport_resource and iomem_resource are filled into the bus->resource[] array as the initial resources in pci_create_bus(). So, to avoid such conflicts, add those really available resources right before returning the newly created bus in pci_create_bus() whose interface should then be extended to receive them. A related discussion thread can be found here: http://www.spinics.net/lists/mips/msg41654.html Signed-off-by: Deng-Cheng Zhu <dczhu@xxxxxxxx> --- Changes (v3 - v2): None Changes (v2 - v1): o Add more info to the patch description. o Fix arch breaks in default resource setup discovered by Bjorn Helgaas. arch/microblaze/pci/pci-common.c | 3 ++- arch/powerpc/kernel/pci-common.c | 3 ++- arch/sparc/kernel/pci.c | 3 ++- arch/x86/pci/acpi.c | 2 +- drivers/pci/probe.c | 15 +++++++++++---- include/linux/pci.h | 3 ++- 6 files changed, 20 insertions(+), 9 deletions(-) diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c index 4cfae20..9c35aa6 100644 --- a/arch/microblaze/pci/pci-common.c +++ b/arch/microblaze/pci/pci-common.c @@ -1581,7 +1581,8 @@ static void __devinit pcibios_scan_phb(struct pci_controller *hose) node ? node->full_name : "<NO NAME>"); /* Create an empty bus for the toplevel */ - bus = pci_create_bus(hose->parent, hose->first_busno, hose->ops, hose); + bus = pci_create_bus(hose->parent, hose->first_busno, + hose->ops, hose, NULL); if (bus == NULL) { printk(KERN_ERR "Failed to create bus for PCI domain %04x\n", hose->global_number); diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index 32656f1..2ede26a 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -1703,7 +1703,8 @@ void __devinit pcibios_scan_phb(struct pci_controller *hose) node ? node->full_name : "<NO NAME>"); /* Create an empty bus for the toplevel */ - bus = pci_create_bus(hose->parent, hose->first_busno, hose->ops, hose); + bus = pci_create_bus(hose->parent, hose->first_busno, + hose->ops, hose, NULL); if (bus == NULL) { pr_err("Failed to create bus for PCI domain %04x\n", hose->global_number); diff --git a/arch/sparc/kernel/pci.c b/arch/sparc/kernel/pci.c index 1e94f94..77c38bb 100644 --- a/arch/sparc/kernel/pci.c +++ b/arch/sparc/kernel/pci.c @@ -689,7 +689,8 @@ struct pci_bus * __devinit pci_scan_one_pbm(struct pci_pbm_info *pbm, printk("PCI: Scanning PBM %s\n", node->full_name); - bus = pci_create_bus(parent, pbm->pci_first_busno, pbm->pci_ops, pbm); + bus = pci_create_bus(parent, pbm->pci_first_busno, + pbm->pci_ops, pbm, NULL); if (!bus) { printk(KERN_ERR "Failed to create bus for %s\n", node->full_name); diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c index c953302..bab2113 100644 --- a/arch/x86/pci/acpi.c +++ b/arch/x86/pci/acpi.c @@ -353,7 +353,7 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root) memcpy(bus->sysdata, sd, sizeof(*sd)); kfree(sd); } else { - bus = pci_create_bus(NULL, busnum, &pci_root_ops, sd); + bus = pci_create_bus(NULL, busnum, &pci_root_ops, sd, NULL); if (bus) { get_current_resources(device, busnum, domain, bus); bus->subordinate = pci_scan_child_bus(bus); diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 8473727..47a364c 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1516,7 +1516,8 @@ unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus) } struct pci_bus * pci_create_bus(struct device *parent, - int bus, struct pci_ops *ops, void *sysdata) + int bus, struct pci_ops *ops, void *sysdata, + struct pci_bus_resource *bus_res) { int error; struct pci_bus *b, *b2; @@ -1570,8 +1571,14 @@ struct pci_bus * pci_create_bus(struct device *parent, pci_create_legacy_files(b); b->number = b->secondary = bus; - b->resource[0] = &ioport_resource; - b->resource[1] = &iomem_resource; + + /* Add initial resources to the bus */ + if (bus_res != NULL) + list_add_tail(&b->resources, &bus_res->list); + else { + b->resource[0] = &ioport_resource; + b->resource[1] = &iomem_resource; + } return b; @@ -1592,7 +1599,7 @@ struct pci_bus * __devinit pci_scan_bus_parented(struct device *parent, { struct pci_bus *b; - b = pci_create_bus(parent, bus, ops, sysdata); + b = pci_create_bus(parent, bus, ops, sysdata, NULL); if (b) b->subordinate = pci_scan_child_bus(b); return b; diff --git a/include/linux/pci.h b/include/linux/pci.h index 8c230cb..5e1bacd 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -666,7 +666,8 @@ static inline struct pci_bus * __devinit pci_scan_bus(int bus, struct pci_ops *o return root_bus; } struct pci_bus *pci_create_bus(struct device *parent, int bus, - struct pci_ops *ops, void *sysdata); + struct pci_ops *ops, void *sysdata, + struct pci_bus_resource *bus_res); struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr); void pcie_update_link_speed(struct pci_bus *bus, u16 link_status); -- 1.7.1