aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/pci/bus.c
blob: eed67d9e73bcd6e3e9ac684342d460a1ac77c62b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
/*
 *	drivers/pci/bus.c
 *
 * From setup-res.c, by:
 *	Dave Rusling (david.rusling@reo.mts.dec.com)
 *	David Mosberger (davidm@cs.arizona.edu)
 *	David Miller (davem@redhat.com)
 *	Ivan Kokshaysky (ink@jurassic.park.msu.ru)
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/proc_fs.h>
#include <linux/init.h>

#include "pci.h"

/**
 * pci_bus_alloc_resource - allocate a resource from a parent bus
 * @bus: PCI bus
 * @res: resource to allocate
 * @size: size of resource to allocate
 * @align: alignment of resource to allocate
 * @min: minimum /proc/iomem address to allocate
 * @type_mask: IORESOURCE_* type flags
 * @alignf: resource alignment function
 * @alignf_data: data argument for resource alignment function
 *
 * Given the PCI bus a device resides on, the size, minimum address,
 * alignment and type, try to find an acceptable resource allocation
 * for a specific device resource.
 */
int
pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
	unsigned long size, unsigned long align, unsigned long min,
	unsigned int type_mask,
	void (*alignf)(void *, struct resource *,
			unsigned long, unsigned long),
	void *alignf_data)
{
	int i, ret = -ENOMEM;

	type_mask |= IORESOURCE_IO | IORESOURCE_MEM;

	for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
		struct resource *r = bus->resource[i];
		if (!r)
			continue;

		/* type_mask must match */
		if ((res->flags ^ r->flags) & type_mask)
			continue;

		/* We cannot allocate a non-prefetching resource
		   from a pre-fetching area */
		if ((r->flags & IORESOURCE_PREFETCH) &&
		    !(res->flags & IORESOURCE_PREFETCH))
			continue;

		/* Ok, try it out.. */
		ret = allocate_resource(r, res, size,
					r->start ? : min,
					-1, align,
					alignf, alignf_data);
		if (ret == 0)
			break;
	}
	return ret;
}

/**
 * add a single device
 * @dev: device to add
 *
 * This adds a single pci device to the global
 * device list and adds sysfs and procfs entries
 */
void __devinit pci_bus_add_device(struct pci_dev *dev)
{
	device_add(&dev->dev);

	spin_lock(&pci_bus_lock);
	list_add_tail(&dev->global_list, &pci_devices);
	spin_unlock(&pci_bus_lock);

	pci_proc_attach_device(dev);
	pci_create_sysfs_dev_files(dev);
}

/**
 * pci_bus_add_devices - insert newly discovered PCI devices
 * @bus: bus to check for new devices
 *
 * Add newly discovered PCI devices (which are on the bus->devices
 * list) to the global PCI device list, add the sysfs and procfs
 * entries.  Where a bridge is found, add the discovered bus to
 * the parents list of child buses, and recurse (breadth-first
 * to be compatible with 2.4)
 *
 * Call hotplug for each new devices.
 */
void __devinit pci_bus_add_devices(struct pci_bus *bus)
{
	struct pci_dev *dev;

	list_for_each_entry(dev, &bus->devices, bus_list) {
		/*
		 * Skip already-present devices (which are on the
		 * global device list.)
		 */
		if (!list_empty(&dev->global_list))
			continue;
		pci_bus_add_device(dev);
	}

	list_for_each_entry(dev, &bus->devices, bus_list) {

		BUG_ON(list_empty(&dev->global_list));

		/*
		 * If there is an unattached subordinate bus, attach
		 * it and then scan for unattached PCI devices.
		 */
		if (dev->subordinate) {
		       if (list_empty(&dev->subordinate->node)) {
			       spin_lock(&pci_bus_lock);
			       list_add_tail(&dev->subordinate->node,
					       &dev->bus->children);
			       spin_unlock(&pci_bus_lock);
		       }
			pci_bus_add_devices(dev->subordinate);

			sysfs_create_link(&dev->subordinate->class_dev.kobj, &dev->dev.kobj, "bridge");
		}
	}
}

void pci_enable_bridges(struct pci_bus *bus)
{
	struct pci_dev *dev;
	int retval;

	list_for_each_entry(dev, &bus->devices, bus_list) {
		if (dev->subordinate) {
			retval = pci_enable_device(dev);
			pci_set_master(dev);
			pci_enable_bridges(dev->subordinate);
		}
	}
}

/** pci_walk_bus - walk devices on/under bus, calling callback.
 *  @top      bus whose devices should be walked
 *  @cb       callback to be called for each device found
 *  @userdata arbitrary pointer to be passed to callback.
 *
 *  Walk the given bus, including any bridged devices
 *  on buses under this bus.  Call the provided callback
 *  on each device found.
 */
void pci_walk_bus(struct pci_bus *top, void (*cb)(struct pci_dev *, void *),
		  void *userdata)
{
	struct pci_dev *dev;
	struct pci_bus *bus;
	struct list_head *next;

	bus = top;
	spin_lock(&pci_bus_lock);
	next = top->devices.next;
	for (;;) {
		if (next == &bus->devices) {
			/* end of this bus, go up or finish */
			if (bus == top)
				break;
			next = bus->self->bus_list.next;
			bus = bus->self->bus;
			continue;
		}
		dev = list_entry(next, struct pci_dev, bus_list);
		pci_dev_get(dev);
		if (dev->subordinate) {
			/* this is a pci-pci bridge, do its devices next */
			next = dev->subordinate->devices.next;
			bus = dev->subordinate;
		} else
			next = dev->bus_list.next;
		spin_unlock(&pci_bus_lock);

		/* Run device routines with the bus unlocked */
		cb(dev, userdata);

		spin_lock(&pci_bus_lock);
		pci_dev_put(dev);
	}
	spin_unlock(&pci_bus_lock);
}
EXPORT_SYMBOL_GPL(pci_walk_bus);

EXPORT_SYMBOL(pci_bus_alloc_resource);
EXPORT_SYMBOL_GPL(pci_bus_add_device);
EXPORT_SYMBOL(pci_bus_add_devices);
EXPORT_SYMBOL(pci_enable_bridges);