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 #undef DEBUG
29
30 #include <linux/pci.h>
31 #include <asm/pci-bridge.h>
32 #include <asm/ppc-pci.h>
33 #include <asm/firmware.h>
34 #include <asm/eeh.h>
35
36 static struct pci_bus *
find_bus_among_children(struct pci_bus * bus,struct device_node * dn)37 find_bus_among_children(struct pci_bus *bus,
38 struct device_node *dn)
39 {
40 struct pci_bus *child = NULL;
41 struct list_head *tmp;
42 struct device_node *busdn;
43
44 busdn = pci_bus_to_OF_node(bus);
45 if (busdn == dn)
46 return bus;
47
48 list_for_each(tmp, &bus->children) {
49 child = find_bus_among_children(pci_bus_b(tmp), dn);
50 if (child)
51 break;
52 };
53 return child;
54 }
55
56 struct pci_bus *
pcibios_find_pci_bus(struct device_node * dn)57 pcibios_find_pci_bus(struct device_node *dn)
58 {
59 struct pci_dn *pdn = dn->data;
60
61 if (!pdn || !pdn->phb || !pdn->phb->bus)
62 return NULL;
63
64 return find_bus_among_children(pdn->phb->bus, dn);
65 }
66 EXPORT_SYMBOL_GPL(pcibios_find_pci_bus);
67
68 /**
69 * pcibios_remove_pci_devices - remove all devices under this bus
70 *
71 * Remove all of the PCI devices under this bus both from the
72 * linux pci device tree, and from the powerpc EEH address cache.
73 */
pcibios_remove_pci_devices(struct pci_bus * bus)74 void pcibios_remove_pci_devices(struct pci_bus *bus)
75 {
76 struct pci_dev *dev, *tmp;
77 struct pci_bus *child_bus;
78
79 /* First go down child busses */
80 list_for_each_entry(child_bus, &bus->children, node)
81 pcibios_remove_pci_devices(child_bus);
82
83 pr_debug("PCI: Removing devices on bus %04x:%02x\n",
84 pci_domain_nr(bus), bus->number);
85 list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
86 pr_debug(" * Removing %s...\n", pci_name(dev));
87 eeh_remove_bus_device(dev);
88 pci_remove_bus_device(dev);
89 }
90 }
91 EXPORT_SYMBOL_GPL(pcibios_remove_pci_devices);
92
93 /**
94 * pcibios_add_pci_devices - adds new pci devices to bus
95 *
96 * This routine will find and fixup new pci devices under
97 * the indicated bus. This routine presumes that there
98 * might already be some devices under this bridge, so
99 * it carefully tries to add only new devices. (And that
100 * is how this routine differs from other, similar pcibios
101 * routines.)
102 */
pcibios_add_pci_devices(struct pci_bus * bus)103 void pcibios_add_pci_devices(struct pci_bus * bus)
104 {
105 int slotno, num, mode, pass, max;
106 struct pci_dev *dev;
107 struct device_node *dn = pci_bus_to_OF_node(bus);
108
109 eeh_add_device_tree_early(dn);
110
111 mode = PCI_PROBE_NORMAL;
112 if (ppc_md.pci_probe_mode)
113 mode = ppc_md.pci_probe_mode(bus);
114
115 if (mode == PCI_PROBE_DEVTREE) {
116 /* use ofdt-based probe */
117 of_rescan_bus(dn, bus);
118 } else if (mode == PCI_PROBE_NORMAL) {
119 /* use legacy probe */
120 slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
121 num = pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
122 if (!num)
123 return;
124 pcibios_setup_bus_devices(bus);
125 max = bus->secondary;
126 for (pass=0; pass < 2; pass++)
127 list_for_each_entry(dev, &bus->devices, bus_list) {
128 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
129 dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
130 max = pci_scan_bridge(bus, dev, max, pass);
131 }
132 }
133 pcibios_finish_adding_to_bus(bus);
134 }
135 EXPORT_SYMBOL_GPL(pcibios_add_pci_devices);
136
init_phb_dynamic(struct device_node * dn)137 struct pci_controller * __devinit init_phb_dynamic(struct device_node *dn)
138 {
139 struct pci_controller *phb;
140 int primary;
141
142 pr_debug("PCI: Initializing new hotplug PHB %s\n", dn->full_name);
143
144 primary = list_empty(&hose_list);
145 phb = pcibios_alloc_controller(dn);
146 if (!phb)
147 return NULL;
148 rtas_setup_phb(phb);
149 pci_process_bridge_OF_ranges(phb, dn, 0);
150
151 pci_devs_phb_init_dynamic(phb);
152
153 if (dn->child)
154 eeh_add_device_tree_early(dn);
155
156 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