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
find_bus_among_children(struct pci_bus * bus,struct device_node * dn)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
pci_find_bus_by_node(struct device_node * dn)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 */
pcibios_release_device(struct pci_dev * dev)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 */
pci_hp_remove_devices(struct pci_bus * bus)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 */
pci_hp_add_devices(struct pci_bus * bus)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