1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Derived from "arch/powerpc/platforms/pseries/pci_dlpar.c" 4 * 5 * Copyright (C) 2003 Linda Xie <lxie@us.ibm.com> 6 * Copyright (C) 2005 International Business Machines 7 * 8 * Updates, 2005, John Rose <johnrose@austin.ibm.com> 9 * Updates, 2005, Linas Vepstas <linas@austin.ibm.com> 10 * Updates, 2013, Gavin Shan <shangw@linux.vnet.ibm.com> 11 */ 12 13 #include <linux/pci.h> 14 #include <linux/export.h> 15 #include <asm/pci-bridge.h> 16 #include <asm/ppc-pci.h> 17 #include <asm/firmware.h> 18 #include <asm/eeh.h> 19 20 static struct pci_bus *find_bus_among_children(struct pci_bus *bus, 21 struct device_node *dn) 22 { 23 struct pci_bus *child = NULL; 24 struct pci_bus *tmp; 25 26 if (pci_bus_to_OF_node(bus) == dn) 27 return bus; 28 29 list_for_each_entry(tmp, &bus->children, node) { 30 child = find_bus_among_children(tmp, dn); 31 if (child) 32 break; 33 } 34 35 return child; 36 } 37 38 struct pci_bus *pci_find_bus_by_node(struct device_node *dn) 39 { 40 struct pci_dn *pdn = PCI_DN(dn); 41 42 if (!pdn || !pdn->phb || !pdn->phb->bus) 43 return NULL; 44 45 return find_bus_among_children(pdn->phb->bus, dn); 46 } 47 EXPORT_SYMBOL_GPL(pci_find_bus_by_node); 48 49 /** 50 * pcibios_release_device - release PCI device 51 * @dev: PCI device 52 * 53 * The function is called before releasing the indicated PCI device. 54 */ 55 void pcibios_release_device(struct pci_dev *dev) 56 { 57 struct pci_controller *phb = pci_bus_to_host(dev->bus); 58 struct pci_dn *pdn = pci_get_pdn(dev); 59 60 if (phb->controller_ops.release_device) 61 phb->controller_ops.release_device(dev); 62 63 /* free()ing the pci_dn has been deferred to us, do it now */ 64 if (pdn && (pdn->flags & PCI_DN_FLAG_DEAD)) { 65 pci_dbg(dev, "freeing dead pdn\n"); 66 kfree(pdn); 67 } 68 } 69 70 /** 71 * pci_hp_remove_devices - remove all devices under this bus 72 * @bus: the indicated PCI bus 73 * 74 * Remove all of the PCI devices under this bus both from the 75 * linux pci device tree, and from the powerpc EEH address cache. 76 */ 77 void pci_hp_remove_devices(struct pci_bus *bus) 78 { 79 struct pci_dev *dev, *tmp; 80 struct pci_bus *child_bus; 81 82 /* First go down child busses */ 83 list_for_each_entry(child_bus, &bus->children, node) 84 pci_hp_remove_devices(child_bus); 85 86 pr_debug("PCI: Removing devices on bus %04x:%02x\n", 87 pci_domain_nr(bus), bus->number); 88 list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) { 89 pr_debug(" Removing %s...\n", pci_name(dev)); 90 pci_stop_and_remove_bus_device(dev); 91 } 92 } 93 EXPORT_SYMBOL_GPL(pci_hp_remove_devices); 94 95 /** 96 * pci_hp_add_devices - adds new pci devices to bus 97 * @bus: the indicated PCI bus 98 * 99 * This routine will find and fixup new pci devices under 100 * the indicated bus. This routine presumes that there 101 * might already be some devices under this bridge, so 102 * it carefully tries to add only new devices. (And that 103 * is how this routine differs from other, similar pcibios 104 * routines.) 105 */ 106 void pci_hp_add_devices(struct pci_bus *bus) 107 { 108 int slotno, mode, max; 109 struct pci_dev *dev; 110 struct pci_controller *phb; 111 struct device_node *dn = pci_bus_to_OF_node(bus); 112 113 phb = pci_bus_to_host(bus); 114 115 mode = PCI_PROBE_NORMAL; 116 if (phb->controller_ops.probe_mode) 117 mode = phb->controller_ops.probe_mode(bus); 118 119 if (mode == PCI_PROBE_DEVTREE) { 120 /* use ofdt-based probe */ 121 of_rescan_bus(dn, bus); 122 } else if (mode == PCI_PROBE_NORMAL && 123 dn->child && PCI_DN(dn->child)) { 124 /* 125 * Use legacy probe. In the partial hotplug case, we 126 * probably have grandchildren devices unplugged. So 127 * we don't check the return value from pci_scan_slot() in 128 * order for fully rescan all the way down to pick them up. 129 * They can have been removed during partial hotplug. 130 */ 131 slotno = PCI_SLOT(PCI_DN(dn->child)->devfn); 132 pci_scan_slot(bus, PCI_DEVFN(slotno, 0)); 133 max = bus->busn_res.start; 134 /* 135 * Scan bridges that are already configured. We don't touch 136 * them unless they are misconfigured (which will be done in 137 * the second scan below). 138 */ 139 for_each_pci_bridge(dev, bus) 140 max = pci_scan_bridge(bus, dev, max, 0); 141 142 /* Scan bridges that need to be reconfigured */ 143 for_each_pci_bridge(dev, bus) 144 max = pci_scan_bridge(bus, dev, max, 1); 145 } 146 pcibios_finish_adding_to_bus(bus); 147 } 148 EXPORT_SYMBOL_GPL(pci_hp_add_devices); 149