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 <linux/of.h> 16 #include <asm/pci-bridge.h> 17 #include <asm/ppc-pci.h> 18 #include <asm/firmware.h> 19 #include <asm/eeh.h> 20 21 static struct pci_bus *find_bus_among_children(struct pci_bus *bus, 22 struct device_node *dn) 23 { 24 struct pci_bus *child = NULL; 25 struct pci_bus *tmp; 26 27 if (pci_bus_to_OF_node(bus) == dn) 28 return bus; 29 30 list_for_each_entry(tmp, &bus->children, node) { 31 child = find_bus_among_children(tmp, dn); 32 if (child) 33 break; 34 } 35 36 return child; 37 } 38 39 struct pci_bus *pci_find_bus_by_node(struct device_node *dn) 40 { 41 struct pci_dn *pdn = PCI_DN(dn); 42 43 if (!pdn || !pdn->phb || !pdn->phb->bus) 44 return NULL; 45 46 return find_bus_among_children(pdn->phb->bus, dn); 47 } 48 EXPORT_SYMBOL_GPL(pci_find_bus_by_node); 49 50 /** 51 * pcibios_release_device - release PCI device 52 * @dev: PCI device 53 * 54 * The function is called before releasing the indicated PCI device. 55 */ 56 void pcibios_release_device(struct pci_dev *dev) 57 { 58 struct pci_controller *phb = pci_bus_to_host(dev->bus); 59 struct pci_dn *pdn = pci_get_pdn(dev); 60 61 if (phb->controller_ops.release_device) 62 phb->controller_ops.release_device(dev); 63 64 /* free()ing the pci_dn has been deferred to us, do it now */ 65 if (pdn && (pdn->flags & PCI_DN_FLAG_DEAD)) { 66 pci_dbg(dev, "freeing dead pdn\n"); 67 kfree(pdn); 68 } 69 } 70 71 /** 72 * pci_hp_remove_devices - remove all devices under this bus 73 * @bus: the indicated PCI bus 74 * 75 * Remove all of the PCI devices under this bus both from the 76 * linux pci device tree, and from the powerpc EEH address cache. 77 */ 78 void pci_hp_remove_devices(struct pci_bus *bus) 79 { 80 struct pci_dev *dev, *tmp; 81 struct pci_bus *child_bus; 82 83 /* First go down child busses */ 84 list_for_each_entry(child_bus, &bus->children, node) 85 pci_hp_remove_devices(child_bus); 86 87 pr_debug("PCI: Removing devices on bus %04x:%02x\n", 88 pci_domain_nr(bus), bus->number); 89 list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) { 90 pr_debug(" Removing %s...\n", pci_name(dev)); 91 pci_stop_and_remove_bus_device(dev); 92 } 93 } 94 EXPORT_SYMBOL_GPL(pci_hp_remove_devices); 95 96 /** 97 * pci_hp_add_devices - adds new pci devices to bus 98 * @bus: the indicated PCI bus 99 * 100 * This routine will find and fixup new pci devices under 101 * the indicated bus. This routine presumes that there 102 * might already be some devices under this bridge, so 103 * it carefully tries to add only new devices. (And that 104 * is how this routine differs from other, similar pcibios 105 * routines.) 106 */ 107 void pci_hp_add_devices(struct pci_bus *bus) 108 { 109 int slotno, mode, max; 110 struct pci_dev *dev; 111 struct pci_controller *phb; 112 struct device_node *dn = pci_bus_to_OF_node(bus); 113 114 phb = pci_bus_to_host(bus); 115 116 mode = PCI_PROBE_NORMAL; 117 if (phb->controller_ops.probe_mode) 118 mode = phb->controller_ops.probe_mode(bus); 119 120 if (mode == PCI_PROBE_DEVTREE) { 121 /* use ofdt-based probe */ 122 of_rescan_bus(dn, bus); 123 } else if (mode == PCI_PROBE_NORMAL && 124 dn->child && PCI_DN(dn->child)) { 125 /* 126 * Use legacy probe. In the partial hotplug case, we 127 * probably have grandchildren devices unplugged. So 128 * we don't check the return value from pci_scan_slot() in 129 * order for fully rescan all the way down to pick them up. 130 * They can have been removed during partial hotplug. 131 */ 132 slotno = PCI_SLOT(PCI_DN(dn->child)->devfn); 133 pci_scan_slot(bus, PCI_DEVFN(slotno, 0)); 134 max = bus->busn_res.start; 135 /* 136 * Scan bridges that are already configured. We don't touch 137 * them unless they are misconfigured (which will be done in 138 * the second scan below). 139 */ 140 for_each_pci_bridge(dev, bus) 141 max = pci_scan_bridge(bus, dev, max, 0); 142 143 /* Scan bridges that need to be reconfigured */ 144 for_each_pci_bridge(dev, bus) 145 max = pci_scan_bridge(bus, dev, max, 1); 146 } 147 pcibios_finish_adding_to_bus(bus); 148 } 149 EXPORT_SYMBOL_GPL(pci_hp_add_devices); 150