Bridges that need bus reassignment are scanned in two passes. Save the firmware secondary bus number during the first pass, before the bridge is disabled, and carry it to the bus created in the second pass. Initialize pci_dev from this preserved bus number so drivers can match firmware records after PCI bus renumbering.
Handle pci_alloc_dev(NULL) as well; some in-tree callers use it to allocate a standalone pci_dev. Signed-off-by: Mario Limonciello <[email protected]> --- drivers/pci/probe.c | 9 +++++++++ include/linux/pci.h | 3 +++ 2 files changed, 12 insertions(+) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 27008e2ea5afc..4ece4b70cdc15 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1012,6 +1012,7 @@ static int pci_register_host_bridge(struct pci_host_bridge *bridge) bus->sysdata = bridge->sysdata; bus->ops = bridge->ops; bus->number = bus->busn_res.start = bridge->busnr; + bus->initial_bus_number = bus->number; #ifdef CONFIG_PCI_DOMAINS_GENERIC if (bridge->domain_nr == PCI_DOMAIN_NR_NOT_SET) bus->domain_nr = pci_bus_find_domain_nr(bus, parent); @@ -1232,6 +1233,7 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent, /* Set up the primary, secondary and subordinate bus numbers */ child->number = child->busn_res.start = busnr; + child->initial_bus_number = busnr; child->primary = parent->busn_res.start; child->busn_res.end = 0xff; @@ -1470,6 +1472,7 @@ static int pci_scan_bridge_extend(struct pci_bus *bus, struct pci_dev *dev, child = pci_add_new_bus(bus, dev, secondary); if (!child) goto out; + child->initial_bus_number = secondary; child->primary = primary; pci_bus_insert_busn_res(child, secondary, subordinate); child->bridge_ctl = bctl; @@ -1491,6 +1494,8 @@ static int pci_scan_bridge_extend(struct pci_bus *bus, struct pci_dev *dev, * do in the second pass. */ if (!pass) { + if (!dev->initial_secondary_bus_number) + dev->initial_secondary_bus_number = secondary; if (pcibios_assign_all_busses() || broken) /* @@ -1526,6 +1531,9 @@ static int pci_scan_bridge_extend(struct pci_bus *bus, struct pci_dev *dev, child = pci_add_new_bus(bus, dev, next_busnr); if (!child) goto out; + if (dev->initial_secondary_bus_number) + child->initial_bus_number = + dev->initial_secondary_bus_number; pci_bus_insert_busn_res(child, next_busnr, bus->busn_res.end); } @@ -2508,6 +2516,7 @@ struct pci_dev *pci_alloc_dev(struct pci_bus *bus) INIT_LIST_HEAD(&dev->bus_list); dev->dev.type = &pci_dev_type; dev->bus = pci_bus_get(bus); + dev->initial_bus_number = bus ? bus->initial_bus_number : 0; dev->driver_exclusive_resource = (struct resource) { .name = "PCI Exclusive", .start = 0, diff --git a/include/linux/pci.h b/include/linux/pci.h index 5ffcf5ce8c966..f6b377dcf7a14 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -363,6 +363,8 @@ struct pci_dev { struct pci_slot *slot; /* Physical slot this device is in */ unsigned int devfn; /* Encoded device & function index */ + u8 initial_bus_number; /* Bus number when device was discovered */ + u8 initial_secondary_bus_number; /* Bus number behind this bridge */ unsigned short vendor; unsigned short device; unsigned short subsystem_vendor; @@ -724,6 +726,7 @@ struct pci_bus { struct proc_dir_entry *procdir; /* Directory entry in /proc/bus/pci */ unsigned char number; /* Bus number */ + unsigned char initial_bus_number; /* Bus number before reassignment */ unsigned char primary; /* Number of primary bridge */ unsigned char max_bus_speed; /* enum pci_bus_speed */ unsigned char cur_bus_speed; /* enum pci_bus_speed */ -- 2.43.0
