1 /*
2 * PCI Dynamic LPAR, PCI Hot Plug and PCI EEH recovery code
3 * for RPA-compliant PPC64 platform.
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 *
10 * All rights reserved.
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or (at
15 * your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful, but
18 * WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
20 * NON INFRINGEMENT. See the GNU General Public License for more
21 * details.
22 *
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26 */
27
28 #include <linux/pci.h>
29 #include <linux/export.h>
30 #include <asm/pci-bridge.h>
31 #include <asm/ppc-pci.h>
32 #include <asm/firmware.h>
33 #include <asm/eeh.h>
34
35 static struct pci_bus *
find_bus_among_children(struct pci_bus * bus,struct device_node * dn)36 find_bus_among_children(struct pci_bus *bus,
37 struct device_node *dn)
38 {
39 struct pci_bus *child = NULL;
40 struct list_head *tmp;
41 struct device_node *busdn;
42
43 busdn = pci_bus_to_OF_node(bus);
44 if (busdn == dn)
45 return bus;
46
47 list_for_each(tmp, &bus->children) {
48 child = find_bus_among_children(pci_bus_b(tmp), dn);
49 if (child)
50 break;
51 };
52 return child;
53 }
54
55 struct pci_bus *
pcibios_find_pci_bus(struct device_node * dn)56 pcibios_find_pci_bus(struct device_node *dn)
57 {
58 struct pci_dn *pdn = dn->data;
59
60 if (!pdn || !pdn->phb || !pdn->phb->bus)
61 return NULL;
62
63 return find_bus_among_children(pdn->phb->bus, dn);
64 }
65 EXPORT_SYMBOL_GPL(pcibios_find_pci_bus);
66
67 /**
68 * pcibios_remove_pci_devices - remove all devices under this bus
69 *
70 * Remove all of the PCI devices under this bus both from the
71 * linux pci device tree, and from the powerpc EEH address cache.
72 */
pcibios_remove_pci_devices(struct pci_bus * bus)73 void pcibios_remove_pci_devices(struct pci_bus *bus)
74 {
75 struct pci_dev *dev, *tmp;
76 struct pci_bus *child_bus;
77
78 /* First go down child busses */
79 list_for_each_entry(child_bus, &bus->children, node)
80 pcibios_remove_pci_devices(child_bus);
81
82 pr_debug("PCI: Removing devices on bus %04x:%02x\n",
83 pci_domain_nr(bus), bus->number);
84 list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
85 pr_debug(" * Removing %s...\n", pci_name(dev));
86 eeh_remove_bus_device(dev);
87 pci_stop_and_remove_bus_device(dev);
88 }
89 }
90 EXPORT_SYMBOL_GPL(pcibios_remove_pci_devices);
91
92 /**
93 * pcibios_add_pci_devices - adds new pci devices to bus
94 *
95 * This routine will find and fixup new pci devices under
96 * the indicated bus. This routine presumes that there
97 * might already be some devices under this bridge, so
98 * it carefully tries to add only new devices. (And that
99 * is how this routine differs from other, similar pcibios
100 * routines.)
101 */
pcibios_add_pci_devices(struct pci_bus * bus)102 void pcibios_add_pci_devices(struct pci_bus * bus)
103 {
104 int slotno, num, mode, pass, max;
105 struct pci_dev *dev;
106 struct device_node *dn = pci_bus_to_OF_node(bus);
107
108 eeh_add_device_tree_early(dn);
109
110 mode = PCI_PROBE_NORMAL;
111 if (ppc_md.pci_probe_mode)
112 mode = ppc_md.pci_probe_mode(bus);
113
114 if (mode == PCI_PROBE_DEVTREE) {
115 /* use ofdt-based probe */
116 of_rescan_bus(dn, bus);
117 } else if (mode == PCI_PROBE_NORMAL) {
118 /* use legacy probe */
119 slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
120 num = pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
121 if (!num)
122 return;
123 pcibios_setup_bus_devices(bus);
124 max = bus->secondary;
125 for (pass=0; pass < 2; pass++)
126 list_for_each_entry(dev, &bus->devices, bus_list) {
127 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
128 dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
129 max = pci_scan_bridge(bus, dev, max, pass);
130 }
131 }
132 pcibios_finish_adding_to_bus(bus);
133 }
134 EXPORT_SYMBOL_GPL(pcibios_add_pci_devices);
135
init_phb_dynamic(struct device_node * dn)136 struct pci_controller * __devinit init_phb_dynamic(struct device_node *dn)
137 {
138 struct pci_controller *phb;
139
140 pr_debug("PCI: Initializing new hotplug PHB %s\n", dn->full_name);
141
142 phb = pcibios_alloc_controller(dn);
143 if (!phb)
144 return NULL;
145 rtas_setup_phb(phb);
146 pci_process_bridge_OF_ranges(phb, dn, 0);
147
148 pci_devs_phb_init_dynamic(phb);
149
150 /* Create EEH devices for the PHB */
151 eeh_dev_phb_init_dynamic(phb);
152
153 if (dn->child)
154 eeh_add_device_tree_early(dn);
155
156 pcibios_scan_phb(phb);
157 pcibios_finish_adding_to_bus(phb->bus);
158
159 return phb;
160 }
161 EXPORT_SYMBOL_GPL(init_phb_dynamic);
162
163 /* RPA-specific bits for removing PHBs */
remove_phb_dynamic(struct pci_controller * phb)164 int remove_phb_dynamic(struct pci_controller *phb)
165 {
166 struct pci_bus *b = phb->bus;
167 struct resource *res;
168 int rc, i;
169
170 pr_debug("PCI: Removing PHB %04x:%02x...\n",
171 pci_domain_nr(b), b->number);
172
173 /* We cannot to remove a root bus that has children */
174 if (!(list_empty(&b->children) && list_empty(&b->devices)))
175 return -EBUSY;
176
177 /* We -know- there aren't any child devices anymore at this stage
178 * and thus, we can safely unmap the IO space as it's not in use
179 */
180 res = &phb->io_resource;
181 if (res->flags & IORESOURCE_IO) {
182 rc = pcibios_unmap_io_space(b);
183 if (rc) {
184 printk(KERN_ERR "%s: failed to unmap IO on bus %s\n",
185 __func__, b->name);
186 return 1;
187 }
188 }
189
190 /* Unregister the bridge device from sysfs and remove the PCI bus */
191 device_unregister(b->bridge);
192 phb->bus = NULL;
193 pci_remove_bus(b);
194
195 /* Now release the IO resource */
196 if (res->flags & IORESOURCE_IO)
197 release_resource(res);
198
199 /* Release memory resources */
200 for (i = 0; i < 3; ++i) {
201 res = &phb->mem_resources[i];
202 if (!(res->flags & IORESOURCE_MEM))
203 continue;
204 release_resource(res);
205 }
206
207 /* Free pci_controller data structure */
208 pcibios_free_controller(phb);
209
210 return 0;
211 }
212 EXPORT_SYMBOL_GPL(remove_phb_dynamic);
213