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 <asm/pci-bridge.h>
30 #include <asm/ppc-pci.h>
31 #include <asm/firmware.h>
32 #include <asm/eeh.h>
33 
34 static struct pci_bus *
35 find_bus_among_children(struct pci_bus *bus,
36                         struct device_node *dn)
37 {
38 	struct pci_bus *child = NULL;
39 	struct list_head *tmp;
40 	struct device_node *busdn;
41 
42 	busdn = pci_bus_to_OF_node(bus);
43 	if (busdn == dn)
44 		return bus;
45 
46 	list_for_each(tmp, &bus->children) {
47 		child = find_bus_among_children(pci_bus_b(tmp), dn);
48 		if (child)
49 			break;
50 	};
51 	return child;
52 }
53 
54 struct pci_bus *
55 pcibios_find_pci_bus(struct device_node *dn)
56 {
57 	struct pci_dn *pdn = dn->data;
58 
59 	if (!pdn  || !pdn->phb || !pdn->phb->bus)
60 		return NULL;
61 
62 	return find_bus_among_children(pdn->phb->bus, dn);
63 }
64 EXPORT_SYMBOL_GPL(pcibios_find_pci_bus);
65 
66 /**
67  * pcibios_remove_pci_devices - remove all devices under this bus
68  *
69  * Remove all of the PCI devices under this bus both from the
70  * linux pci device tree, and from the powerpc EEH address cache.
71  */
72 void
73 pcibios_remove_pci_devices(struct pci_bus *bus)
74 {
75 	struct pci_dev *dev, *tmp;
76 
77 	list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
78 		eeh_remove_bus_device(dev);
79 		pci_remove_bus_device(dev);
80 	}
81 }
82 EXPORT_SYMBOL_GPL(pcibios_remove_pci_devices);
83 
84 /* Must be called before pci_bus_add_devices */
85 void
86 pcibios_fixup_new_pci_devices(struct pci_bus *bus, int fix_bus)
87 {
88 	struct pci_dev *dev;
89 
90 	list_for_each_entry(dev, &bus->devices, bus_list) {
91 		/*
92 		 * Skip already-present devices (which are on the
93 		 * global device list.)
94 		 */
95 		if (list_empty(&dev->global_list)) {
96 			int i;
97 
98 			/* Fill device archdata and setup iommu table */
99 			pcibios_setup_new_device(dev);
100 
101 			if(fix_bus)
102 				pcibios_fixup_device_resources(dev, bus);
103 			pci_read_irq_line(dev);
104 			for (i = 0; i < PCI_NUM_RESOURCES; i++) {
105 				struct resource *r = &dev->resource[i];
106 
107 				if (r->parent || !r->start || !r->flags)
108 					continue;
109 				pci_claim_resource(dev, i);
110 			}
111 		}
112 	}
113 }
114 EXPORT_SYMBOL_GPL(pcibios_fixup_new_pci_devices);
115 
116 static int
117 pcibios_pci_config_bridge(struct pci_dev *dev)
118 {
119 	u8 sec_busno;
120 	struct pci_bus *child_bus;
121 
122 	/* Get busno of downstream bus */
123 	pci_read_config_byte(dev, PCI_SECONDARY_BUS, &sec_busno);
124 
125 	/* Add to children of PCI bridge dev->bus */
126 	child_bus = pci_add_new_bus(dev->bus, dev, sec_busno);
127 	if (!child_bus) {
128 		printk (KERN_ERR "%s: could not add second bus\n", __FUNCTION__);
129 		return -EIO;
130 	}
131 	sprintf(child_bus->name, "PCI Bus #%02x", child_bus->number);
132 
133 	pci_scan_child_bus(child_bus);
134 
135 	/* Fixup new pci devices without touching bus struct */
136 	pcibios_fixup_new_pci_devices(child_bus, 0);
137 
138 	/* Make the discovered devices available */
139 	pci_bus_add_devices(child_bus);
140 
141 	eeh_add_device_tree_late(child_bus);
142 	return 0;
143 }
144 
145 /**
146  * pcibios_add_pci_devices - adds new pci devices to bus
147  *
148  * This routine will find and fixup new pci devices under
149  * the indicated bus. This routine presumes that there
150  * might already be some devices under this bridge, so
151  * it carefully tries to add only new devices.  (And that
152  * is how this routine differs from other, similar pcibios
153  * routines.)
154  */
155 void
156 pcibios_add_pci_devices(struct pci_bus * bus)
157 {
158 	int slotno, num, mode;
159 	struct pci_dev *dev;
160 	struct device_node *dn = pci_bus_to_OF_node(bus);
161 
162 	eeh_add_device_tree_early(dn);
163 
164 	mode = PCI_PROBE_NORMAL;
165 	if (ppc_md.pci_probe_mode)
166 		mode = ppc_md.pci_probe_mode(bus);
167 
168 	if (mode == PCI_PROBE_DEVTREE) {
169 		/* use ofdt-based probe */
170 		of_scan_bus(dn, bus);
171 		if (!list_empty(&bus->devices)) {
172 			pcibios_fixup_new_pci_devices(bus, 0);
173 			pci_bus_add_devices(bus);
174 			eeh_add_device_tree_late(bus);
175 		}
176 	} else if (mode == PCI_PROBE_NORMAL) {
177 		/* use legacy probe */
178 		slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
179 		num = pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
180 		if (num) {
181 			pcibios_fixup_new_pci_devices(bus, 1);
182 			pci_bus_add_devices(bus);
183 			eeh_add_device_tree_late(bus);
184 		}
185 
186 		list_for_each_entry(dev, &bus->devices, bus_list)
187 			if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
188 				pcibios_pci_config_bridge(dev);
189 	}
190 }
191 EXPORT_SYMBOL_GPL(pcibios_add_pci_devices);
192 
193 struct pci_controller * __devinit init_phb_dynamic(struct device_node *dn)
194 {
195 	struct pci_controller *phb;
196 	int primary;
197 
198 	primary = list_empty(&hose_list);
199 	phb = pcibios_alloc_controller(dn);
200 	if (!phb)
201 		return NULL;
202 	rtas_setup_phb(phb);
203 	pci_process_bridge_OF_ranges(phb, dn, 0);
204 
205 	pci_devs_phb_init_dynamic(phb);
206 
207 	if (dn->child)
208 		eeh_add_device_tree_early(dn);
209 
210 	scan_phb(phb);
211 	pcibios_fixup_new_pci_devices(phb->bus, 0);
212 	pci_bus_add_devices(phb->bus);
213 	eeh_add_device_tree_late(phb->bus);
214 
215 	return phb;
216 }
217 EXPORT_SYMBOL_GPL(init_phb_dynamic);
218