xref: /linux/arch/powerpc/kernel/pci-hotplug.c (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
1 /*
2  * Derived from "arch/powerpc/platforms/pseries/pci_dlpar.c"
3  *
4  * Copyright (C) 2003 Linda Xie <lxie@us.ibm.com>
5  * Copyright (C) 2005 International Business Machines
6  *
7  * Updates, 2005, John Rose <johnrose@austin.ibm.com>
8  * Updates, 2005, Linas Vepstas <linas@austin.ibm.com>
9  * Updates, 2013, Gavin Shan <shangw@linux.vnet.ibm.com>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  */
16 
17 #include <linux/pci.h>
18 #include <linux/export.h>
19 #include <asm/pci-bridge.h>
20 #include <asm/ppc-pci.h>
21 #include <asm/firmware.h>
22 #include <asm/eeh.h>
23 
24 /**
25  * pcibios_release_device - release PCI device
26  * @dev: PCI device
27  *
28  * The function is called before releasing the indicated PCI device.
29  */
30 void pcibios_release_device(struct pci_dev *dev)
31 {
32 	struct pci_controller *phb = pci_bus_to_host(dev->bus);
33 
34 	eeh_remove_device(dev);
35 
36 	if (phb->controller_ops.release_device)
37 		phb->controller_ops.release_device(dev);
38 }
39 
40 /**
41  * pcibios_remove_pci_devices - remove all devices under this bus
42  * @bus: the indicated PCI bus
43  *
44  * Remove all of the PCI devices under this bus both from the
45  * linux pci device tree, and from the powerpc EEH address cache.
46  */
47 void pcibios_remove_pci_devices(struct pci_bus *bus)
48 {
49 	struct pci_dev *dev, *tmp;
50 	struct pci_bus *child_bus;
51 
52 	/* First go down child busses */
53 	list_for_each_entry(child_bus, &bus->children, node)
54 		pcibios_remove_pci_devices(child_bus);
55 
56 	pr_debug("PCI: Removing devices on bus %04x:%02x\n",
57 		 pci_domain_nr(bus),  bus->number);
58 	list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
59 		pr_debug("   Removing %s...\n", pci_name(dev));
60 		pci_stop_and_remove_bus_device(dev);
61 	}
62 }
63 
64 EXPORT_SYMBOL_GPL(pcibios_remove_pci_devices);
65 
66 /**
67  * pcibios_add_pci_devices - adds new pci devices to bus
68  * @bus: the indicated PCI bus
69  *
70  * This routine will find and fixup new pci devices under
71  * the indicated bus. This routine presumes that there
72  * might already be some devices under this bridge, so
73  * it carefully tries to add only new devices.  (And that
74  * is how this routine differs from other, similar pcibios
75  * routines.)
76  */
77 void pcibios_add_pci_devices(struct pci_bus * bus)
78 {
79 	int slotno, mode, pass, max;
80 	struct pci_dev *dev;
81 	struct pci_controller *phb;
82 	struct device_node *dn = pci_bus_to_OF_node(bus);
83 
84 	eeh_add_device_tree_early(PCI_DN(dn));
85 
86 	phb = pci_bus_to_host(bus);
87 
88 	mode = PCI_PROBE_NORMAL;
89 	if (phb->controller_ops.probe_mode)
90 		mode = phb->controller_ops.probe_mode(bus);
91 
92 	if (mode == PCI_PROBE_DEVTREE) {
93 		/* use ofdt-based probe */
94 		of_rescan_bus(dn, bus);
95 	} else if (mode == PCI_PROBE_NORMAL) {
96 		/*
97 		 * Use legacy probe. In the partial hotplug case, we
98 		 * probably have grandchildren devices unplugged. So
99 		 * we don't check the return value from pci_scan_slot() in
100 		 * order for fully rescan all the way down to pick them up.
101 		 * They can have been removed during partial hotplug.
102 		 */
103 		slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
104 		pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
105 		pcibios_setup_bus_devices(bus);
106 		max = bus->busn_res.start;
107 		for (pass = 0; pass < 2; pass++) {
108 			list_for_each_entry(dev, &bus->devices, bus_list) {
109 				if (pci_is_bridge(dev))
110 					max = pci_scan_bridge(bus, dev,
111 							      max, pass);
112 			}
113 		}
114 	}
115 	pcibios_finish_adding_to_bus(bus);
116 }
117 EXPORT_SYMBOL_GPL(pcibios_add_pci_devices);
118