From c0fa40784cce9cc66b54499a3762cfe07e35353f Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Fri, 22 Jun 2012 14:55:17 +0800 Subject: x86/PCI: update MMCONFIG information when hot-plugging PCI host bridges This patch enhances x86 arch-specific code to update MMCONFIG information when PCI host bridge hotplug event happens. Reviewed-by: Yinghai Lu Signed-off-by: Jiang Liu Signed-off-by: Bjorn Helgaas --- arch/x86/pci/acpi.c | 93 +++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 90 insertions(+), 3 deletions(-) (limited to 'arch/x86/pci/acpi.c') diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c index 2bb885afe103..912b54b26d6a 100644 --- a/arch/x86/pci/acpi.c +++ b/arch/x86/pci/acpi.c @@ -13,6 +13,12 @@ struct pci_root_info { unsigned int res_num; struct resource *res; struct pci_sysdata sd; +#ifdef CONFIG_PCI_MMCONFIG + bool mcfg_added; + u16 segment; + u8 start_bus; + u8 end_bus; +#endif }; static bool pci_use_crs = true; @@ -119,6 +125,81 @@ void __init pci_acpi_crs_quirks(void) pci_use_crs ? "nocrs" : "use_crs"); } +#ifdef CONFIG_PCI_MMCONFIG +static int __devinit check_segment(u16 seg, struct device *dev, char *estr) +{ + if (seg) { + dev_err(dev, + "%s can't access PCI configuration " + "space under this host bridge.\n", + estr); + return -EIO; + } + + /* + * Failure in adding MMCFG information is not fatal, + * just can't access extended configuration space of + * devices under this host bridge. + */ + dev_warn(dev, + "%s can't access extended PCI configuration " + "space under this bridge.\n", + estr); + + return 0; +} + +static int __devinit setup_mcfg_map(struct pci_root_info *info, + u16 seg, u8 start, u8 end, + phys_addr_t addr) +{ + int result; + struct device *dev = &info->bridge->dev; + + info->start_bus = start; + info->end_bus = end; + info->mcfg_added = false; + + /* return success if MMCFG is not in use */ + if (raw_pci_ext_ops && raw_pci_ext_ops != &pci_mmcfg) + return 0; + + if (!(pci_probe & PCI_PROBE_MMCONF)) + return check_segment(seg, dev, "MMCONFIG is disabled,"); + + result = pci_mmconfig_insert(dev, seg, start, end, addr); + if (result == 0) { + /* enable MMCFG if it hasn't been enabled yet */ + if (raw_pci_ext_ops == NULL) + raw_pci_ext_ops = &pci_mmcfg; + info->mcfg_added = true; + } else if (result != -EEXIST) + return check_segment(seg, dev, + "fail to add MMCONFIG information,"); + + return 0; +} + +static void teardown_mcfg_map(struct pci_root_info *info) +{ + if (info->mcfg_added) { + pci_mmconfig_delete(info->segment, info->start_bus, + info->end_bus); + info->mcfg_added = false; + } +} +#else +static int __devinit setup_mcfg_map(struct pci_root_info *info, + u16 seg, u8 start, u8 end, + phys_addr_t addr) +{ + return 0; +} +static void teardown_mcfg_map(struct pci_root_info *info) +{ +} +#endif + static acpi_status resource_to_addr(struct acpi_resource *resource, struct acpi_resource_address64 *addr) @@ -331,8 +412,11 @@ static void __release_pci_root_info(struct pci_root_info *info) free_pci_root_info_res(info); + teardown_mcfg_map(info); + kfree(info); } + static void release_pci_root_info(struct pci_host_bridge *bridge) { struct pci_root_info *info = bridge->release_data; @@ -372,7 +456,7 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root) int domain = root->segment; int busnum = root->secondary.start; LIST_HEAD(resources); - struct pci_bus *bus; + struct pci_bus *bus = NULL; struct pci_sysdata *sd; int node; #ifdef CONFIG_ACPI_NUMA @@ -438,8 +522,11 @@ struct pci_bus * __devinit pci_acpi_scan_root(struct acpi_pci_root *root) x86_pci_root_bus_resources(busnum, &resources); } - bus = pci_create_root_bus(NULL, busnum, &pci_root_ops, sd, - &resources); + if (!setup_mcfg_map(info, domain, (u8)root->secondary.start, + (u8)root->secondary.end, root->mcfg_addr)) + bus = pci_create_root_bus(NULL, busnum, &pci_root_ops, + sd, &resources); + if (bus) { pci_scan_child_bus(bus); pci_set_host_bridge_release( -- cgit v1.2.3