arm64: dts: Revert "specify console via command line"
[linux/fpc-iii.git] / arch / powerpc / kernel / pci-hotplug.c
blobd6a67f814983d05c1b6fa299f3db638c1b216df3
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Derived from "arch/powerpc/platforms/pseries/pci_dlpar.c"
5 * Copyright (C) 2003 Linda Xie <lxie@us.ibm.com>
6 * Copyright (C) 2005 International Business Machines
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>
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>
20 static struct pci_bus *find_bus_among_children(struct pci_bus *bus,
21 struct device_node *dn)
23 struct pci_bus *child = NULL;
24 struct pci_bus *tmp;
26 if (pci_bus_to_OF_node(bus) == dn)
27 return bus;
29 list_for_each_entry(tmp, &bus->children, node) {
30 child = find_bus_among_children(tmp, dn);
31 if (child)
32 break;
35 return child;
38 struct pci_bus *pci_find_bus_by_node(struct device_node *dn)
40 struct pci_dn *pdn = PCI_DN(dn);
42 if (!pdn || !pdn->phb || !pdn->phb->bus)
43 return NULL;
45 return find_bus_among_children(pdn->phb->bus, dn);
47 EXPORT_SYMBOL_GPL(pci_find_bus_by_node);
49 /**
50 * pcibios_release_device - release PCI device
51 * @dev: PCI device
53 * The function is called before releasing the indicated PCI device.
55 void pcibios_release_device(struct pci_dev *dev)
57 struct pci_controller *phb = pci_bus_to_host(dev->bus);
58 struct pci_dn *pdn = pci_get_pdn(dev);
60 eeh_remove_device(dev);
62 if (phb->controller_ops.release_device)
63 phb->controller_ops.release_device(dev);
65 /* free()ing the pci_dn has been deferred to us, do it now */
66 if (pdn && (pdn->flags & PCI_DN_FLAG_DEAD)) {
67 pci_dbg(dev, "freeing dead pdn\n");
68 kfree(pdn);
72 /**
73 * pci_hp_remove_devices - remove all devices under this bus
74 * @bus: the indicated PCI bus
76 * Remove all of the PCI devices under this bus both from the
77 * linux pci device tree, and from the powerpc EEH address cache.
79 void pci_hp_remove_devices(struct pci_bus *bus)
81 struct pci_dev *dev, *tmp;
82 struct pci_bus *child_bus;
84 /* First go down child busses */
85 list_for_each_entry(child_bus, &bus->children, node)
86 pci_hp_remove_devices(child_bus);
88 pr_debug("PCI: Removing devices on bus %04x:%02x\n",
89 pci_domain_nr(bus), bus->number);
90 list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
91 pr_debug(" Removing %s...\n", pci_name(dev));
92 pci_stop_and_remove_bus_device(dev);
95 EXPORT_SYMBOL_GPL(pci_hp_remove_devices);
97 /**
98 * pci_hp_add_devices - adds new pci devices to bus
99 * @bus: the indicated PCI bus
101 * This routine will find and fixup new pci devices under
102 * the indicated bus. This routine presumes that there
103 * might already be some devices under this bridge, so
104 * it carefully tries to add only new devices. (And that
105 * is how this routine differs from other, similar pcibios
106 * routines.)
108 void pci_hp_add_devices(struct pci_bus *bus)
110 int slotno, mode, max;
111 struct pci_dev *dev;
112 struct pci_controller *phb;
113 struct device_node *dn = pci_bus_to_OF_node(bus);
115 eeh_add_device_tree_early(PCI_DN(dn));
117 phb = pci_bus_to_host(bus);
119 mode = PCI_PROBE_NORMAL;
120 if (phb->controller_ops.probe_mode)
121 mode = phb->controller_ops.probe_mode(bus);
123 if (mode == PCI_PROBE_DEVTREE) {
124 /* use ofdt-based probe */
125 of_rescan_bus(dn, bus);
126 } else if (mode == PCI_PROBE_NORMAL &&
127 dn->child && PCI_DN(dn->child)) {
129 * Use legacy probe. In the partial hotplug case, we
130 * probably have grandchildren devices unplugged. So
131 * we don't check the return value from pci_scan_slot() in
132 * order for fully rescan all the way down to pick them up.
133 * They can have been removed during partial hotplug.
135 slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
136 pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
137 max = bus->busn_res.start;
139 * Scan bridges that are already configured. We don't touch
140 * them unless they are misconfigured (which will be done in
141 * the second scan below).
143 for_each_pci_bridge(dev, bus)
144 max = pci_scan_bridge(bus, dev, max, 0);
146 /* Scan bridges that need to be reconfigured */
147 for_each_pci_bridge(dev, bus)
148 max = pci_scan_bridge(bus, dev, max, 1);
150 pcibios_finish_adding_to_bus(bus);
152 EXPORT_SYMBOL_GPL(pci_hp_add_devices);