blob: 659eaa0fc48facf81dad9c0b5c430498e01398e3 [file] [log] [blame]
Alex Chiangf46753c2008-06-10 15:28:50 -06001/*
2 * drivers/pci/slot.c
3 * Copyright (C) 2006 Matthew Wilcox <matthew@wil.cx>
Alex Chiang62795042009-02-04 11:25:22 -07004 * Copyright (C) 2006-2009 Hewlett-Packard Development Company, L.P.
5 * Alex Chiang <achiang@hp.com>
Alex Chiangf46753c2008-06-10 15:28:50 -06006 */
7
8#include <linux/kobject.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +09009#include <linux/slab.h>
Alex Chiangf46753c2008-06-10 15:28:50 -060010#include <linux/pci.h>
11#include <linux/err.h>
12#include "pci.h"
13
14struct kset *pci_slots_kset;
15EXPORT_SYMBOL_GPL(pci_slots_kset);
16
17static ssize_t pci_slot_attr_show(struct kobject *kobj,
18 struct attribute *attr, char *buf)
19{
20 struct pci_slot *slot = to_pci_slot(kobj);
21 struct pci_slot_attribute *attribute = to_pci_slot_attr(attr);
22 return attribute->show ? attribute->show(slot, buf) : -EIO;
23}
24
25static ssize_t pci_slot_attr_store(struct kobject *kobj,
26 struct attribute *attr, const char *buf, size_t len)
27{
28 struct pci_slot *slot = to_pci_slot(kobj);
29 struct pci_slot_attribute *attribute = to_pci_slot_attr(attr);
30 return attribute->store ? attribute->store(slot, buf, len) : -EIO;
31}
32
Emese Revfy52cf25d2010-01-19 02:58:23 +010033static const struct sysfs_ops pci_slot_sysfs_ops = {
Alex Chiangf46753c2008-06-10 15:28:50 -060034 .show = pci_slot_attr_show,
35 .store = pci_slot_attr_store,
36};
37
38static ssize_t address_read_file(struct pci_slot *slot, char *buf)
39{
40 if (slot->number == 0xff)
41 return sprintf(buf, "%04x:%02x\n",
42 pci_domain_nr(slot->bus),
43 slot->bus->number);
44 else
45 return sprintf(buf, "%04x:%02x:%02x\n",
46 pci_domain_nr(slot->bus),
47 slot->bus->number,
48 slot->number);
49}
50
Matthew Wilcox3749c512009-12-13 08:11:32 -050051/* these strings match up with the values in pci_bus_speed */
52static char *pci_bus_speed_strings[] = {
53 "33 MHz PCI", /* 0x00 */
54 "66 MHz PCI", /* 0x01 */
55 "66 MHz PCI-X", /* 0x02 */
56 "100 MHz PCI-X", /* 0x03 */
57 "133 MHz PCI-X", /* 0x04 */
58 NULL, /* 0x05 */
59 NULL, /* 0x06 */
60 NULL, /* 0x07 */
61 NULL, /* 0x08 */
62 "66 MHz PCI-X 266", /* 0x09 */
63 "100 MHz PCI-X 266", /* 0x0a */
64 "133 MHz PCI-X 266", /* 0x0b */
Matthew Wilcox45b4cdd52009-12-13 08:11:34 -050065 "Unknown AGP", /* 0x0c */
66 "1x AGP", /* 0x0d */
67 "2x AGP", /* 0x0e */
68 "4x AGP", /* 0x0f */
69 "8x AGP", /* 0x10 */
Matthew Wilcox3749c512009-12-13 08:11:32 -050070 "66 MHz PCI-X 533", /* 0x11 */
71 "100 MHz PCI-X 533", /* 0x12 */
72 "133 MHz PCI-X 533", /* 0x13 */
73 "2.5 GT/s PCIe", /* 0x14 */
74 "5.0 GT/s PCIe", /* 0x15 */
Matthew Wilcox9dfd97f2009-12-13 08:11:35 -050075 "8.0 GT/s PCIe", /* 0x16 */
Matthew Wilcox3749c512009-12-13 08:11:32 -050076};
77
78static ssize_t bus_speed_read(enum pci_bus_speed speed, char *buf)
79{
80 const char *speed_string;
81
82 if (speed < ARRAY_SIZE(pci_bus_speed_strings))
83 speed_string = pci_bus_speed_strings[speed];
84 else
85 speed_string = "Unknown";
86
87 return sprintf(buf, "%s\n", speed_string);
88}
89
90static ssize_t max_speed_read_file(struct pci_slot *slot, char *buf)
91{
92 return bus_speed_read(slot->bus->max_bus_speed, buf);
93}
94
95static ssize_t cur_speed_read_file(struct pci_slot *slot, char *buf)
96{
97 return bus_speed_read(slot->bus->cur_bus_speed, buf);
98}
99
Alex Chiangf46753c2008-06-10 15:28:50 -0600100static void pci_slot_release(struct kobject *kobj)
101{
Alex Chiangcef354d2008-09-02 09:40:51 -0600102 struct pci_dev *dev;
Alex Chiangf46753c2008-06-10 15:28:50 -0600103 struct pci_slot *slot = to_pci_slot(kobj);
104
Alex Chiang62795042009-02-04 11:25:22 -0700105 dev_dbg(&slot->bus->dev, "dev %02x, released physical slot %s\n",
106 slot->number, pci_slot_name(slot));
Alex Chiangf46753c2008-06-10 15:28:50 -0600107
Alex Chiangcef354d2008-09-02 09:40:51 -0600108 list_for_each_entry(dev, &slot->bus->devices, bus_list)
109 if (PCI_SLOT(dev->devfn) == slot->number)
110 dev->slot = NULL;
111
Alex Chiangf46753c2008-06-10 15:28:50 -0600112 list_del(&slot->list);
113
114 kfree(slot);
115}
116
117static struct pci_slot_attribute pci_slot_attr_address =
118 __ATTR(address, (S_IFREG | S_IRUGO), address_read_file, NULL);
Matthew Wilcox3749c512009-12-13 08:11:32 -0500119static struct pci_slot_attribute pci_slot_attr_max_speed =
120 __ATTR(max_bus_speed, (S_IFREG | S_IRUGO), max_speed_read_file, NULL);
121static struct pci_slot_attribute pci_slot_attr_cur_speed =
122 __ATTR(cur_bus_speed, (S_IFREG | S_IRUGO), cur_speed_read_file, NULL);
Alex Chiangf46753c2008-06-10 15:28:50 -0600123
124static struct attribute *pci_slot_default_attrs[] = {
125 &pci_slot_attr_address.attr,
Matthew Wilcox3749c512009-12-13 08:11:32 -0500126 &pci_slot_attr_max_speed.attr,
127 &pci_slot_attr_cur_speed.attr,
Alex Chiangf46753c2008-06-10 15:28:50 -0600128 NULL,
129};
130
131static struct kobj_type pci_slot_ktype = {
132 .sysfs_ops = &pci_slot_sysfs_ops,
133 .release = &pci_slot_release,
134 .default_attrs = pci_slot_default_attrs,
135};
136
Alex Chiang5fe6cc62008-10-20 17:41:02 -0600137static char *make_slot_name(const char *name)
138{
139 char *new_name;
140 int len, max, dup;
141
142 new_name = kstrdup(name, GFP_KERNEL);
143 if (!new_name)
144 return NULL;
145
146 /*
147 * Make sure we hit the realloc case the first time through the
148 * loop. 'len' will be strlen(name) + 3 at that point which is
149 * enough space for "name-X" and the trailing NUL.
150 */
151 len = strlen(name) + 2;
152 max = 1;
153 dup = 1;
154
155 for (;;) {
156 struct kobject *dup_slot;
157 dup_slot = kset_find_obj(pci_slots_kset, new_name);
158 if (!dup_slot)
159 break;
160 kobject_put(dup_slot);
161 if (dup == max) {
162 len++;
163 max *= 10;
164 kfree(new_name);
165 new_name = kmalloc(len, GFP_KERNEL);
166 if (!new_name)
167 break;
168 }
169 sprintf(new_name, "%s-%d", name, dup++);
170 }
171
172 return new_name;
173}
174
175static int rename_slot(struct pci_slot *slot, const char *name)
176{
177 int result = 0;
178 char *slot_name;
179
Alex Chiang0ad772e2008-10-20 17:41:07 -0600180 if (strcmp(pci_slot_name(slot), name) == 0)
Alex Chiang5fe6cc62008-10-20 17:41:02 -0600181 return result;
182
183 slot_name = make_slot_name(name);
184 if (!slot_name)
185 return -ENOMEM;
186
187 result = kobject_rename(&slot->kobj, slot_name);
188 kfree(slot_name);
189
190 return result;
191}
192
193static struct pci_slot *get_slot(struct pci_bus *parent, int slot_nr)
194{
195 struct pci_slot *slot;
196 /*
197 * We already hold pci_bus_sem so don't worry
198 */
199 list_for_each_entry(slot, &parent->slots, list)
200 if (slot->number == slot_nr) {
201 kobject_get(&slot->kobj);
202 return slot;
203 }
204
205 return NULL;
206}
207
Alex Chiangf46753c2008-06-10 15:28:50 -0600208/**
209 * pci_create_slot - create or increment refcount for physical PCI slot
210 * @parent: struct pci_bus of parent bridge
211 * @slot_nr: PCI_SLOT(pci_dev->devfn) or -1 for placeholder
212 * @name: user visible string presented in /sys/bus/pci/slots/<name>
Alex Chiang828f3762008-10-20 17:40:52 -0600213 * @hotplug: set if caller is hotplug driver, NULL otherwise
Alex Chiangf46753c2008-06-10 15:28:50 -0600214 *
215 * PCI slots have first class attributes such as address, speed, width,
216 * and a &struct pci_slot is used to manage them. This interface will
217 * either return a new &struct pci_slot to the caller, or if the pci_slot
218 * already exists, its refcount will be incremented.
219 *
Alex Chiang5fe6cc62008-10-20 17:41:02 -0600220 * Slots are uniquely identified by a @pci_bus, @slot_nr tuple.
221 *
222 * There are known platforms with broken firmware that assign the same
223 * name to multiple slots. Workaround these broken platforms by renaming
224 * the slots on behalf of the caller. If firmware assigns name N to
225 * multiple slots:
226 *
227 * The first slot is assigned N
228 * The second slot is assigned N-1
229 * The third slot is assigned N-2
230 * etc.
Alex Chiangf46753c2008-06-10 15:28:50 -0600231 *
232 * Placeholder slots:
233 * In most cases, @pci_bus, @slot_nr will be sufficient to uniquely identify
234 * a slot. There is one notable exception - pSeries (rpaphp), where the
235 * @slot_nr cannot be determined until a device is actually inserted into
236 * the slot. In this scenario, the caller may pass -1 for @slot_nr.
237 *
238 * The following semantics are imposed when the caller passes @slot_nr ==
Alex Chiang5fe6cc62008-10-20 17:41:02 -0600239 * -1. First, we no longer check for an existing %struct pci_slot, as there
240 * may be many slots with @slot_nr of -1. The other change in semantics is
Alex Chiangf46753c2008-06-10 15:28:50 -0600241 * user-visible, which is the 'address' parameter presented in sysfs will
242 * consist solely of a dddd:bb tuple, where dddd is the PCI domain of the
243 * %struct pci_bus and bb is the bus number. In other words, the devfn of
244 * the 'placeholder' slot will not be displayed.
245 */
Alex Chiangf46753c2008-06-10 15:28:50 -0600246struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
Alex Chiang828f3762008-10-20 17:40:52 -0600247 const char *name,
248 struct hotplug_slot *hotplug)
Alex Chiangf46753c2008-06-10 15:28:50 -0600249{
Alex Chiangcef354d2008-09-02 09:40:51 -0600250 struct pci_dev *dev;
Alex Chiangf46753c2008-06-10 15:28:50 -0600251 struct pci_slot *slot;
Alex Chiang5fe6cc62008-10-20 17:41:02 -0600252 int err = 0;
253 char *slot_name = NULL;
Alex Chiangf46753c2008-06-10 15:28:50 -0600254
255 down_write(&pci_bus_sem);
256
257 if (slot_nr == -1)
258 goto placeholder;
259
Alex Chiang5fe6cc62008-10-20 17:41:02 -0600260 /*
261 * Hotplug drivers are allowed to rename an existing slot,
262 * but only if not already claimed.
263 */
264 slot = get_slot(parent, slot_nr);
265 if (slot) {
266 if (hotplug) {
267 if ((err = slot->hotplug ? -EBUSY : 0)
268 || (err = rename_slot(slot, name))) {
269 kobject_put(&slot->kobj);
270 slot = NULL;
271 goto err;
272 }
Alex Chiangf46753c2008-06-10 15:28:50 -0600273 }
Alex Chiang5fe6cc62008-10-20 17:41:02 -0600274 goto out;
Alex Chiangf46753c2008-06-10 15:28:50 -0600275 }
276
277placeholder:
278 slot = kzalloc(sizeof(*slot), GFP_KERNEL);
279 if (!slot) {
Alex Chiang5fe6cc62008-10-20 17:41:02 -0600280 err = -ENOMEM;
281 goto err;
Alex Chiangf46753c2008-06-10 15:28:50 -0600282 }
283
284 slot->bus = parent;
285 slot->number = slot_nr;
286
287 slot->kobj.kset = pci_slots_kset;
Alex Chiang5fe6cc62008-10-20 17:41:02 -0600288
289 slot_name = make_slot_name(name);
290 if (!slot_name) {
291 err = -ENOMEM;
Alex Chiangf46753c2008-06-10 15:28:50 -0600292 goto err;
293 }
294
Alex Chiang5fe6cc62008-10-20 17:41:02 -0600295 err = kobject_init_and_add(&slot->kobj, &pci_slot_ktype, NULL,
296 "%s", slot_name);
297 if (err)
298 goto err;
299
Alex Chiangf46753c2008-06-10 15:28:50 -0600300 INIT_LIST_HEAD(&slot->list);
301 list_add(&slot->list, &parent->slots);
302
Alex Chiangcef354d2008-09-02 09:40:51 -0600303 list_for_each_entry(dev, &parent->devices, bus_list)
304 if (PCI_SLOT(dev->devfn) == slot_nr)
305 dev->slot = slot;
306
Alex Chiang62795042009-02-04 11:25:22 -0700307 dev_dbg(&parent->dev, "dev %02x, created physical slot %s\n",
308 slot_nr, pci_slot_name(slot));
Alex Chiangf46753c2008-06-10 15:28:50 -0600309
Alex Chiang5fe6cc62008-10-20 17:41:02 -0600310out:
Alex Chiang3b5dd452008-12-01 18:17:21 -0700311 kfree(slot_name);
Alex Chiangf46753c2008-06-10 15:28:50 -0600312 up_write(&pci_bus_sem);
313 return slot;
Alex Chiang5fe6cc62008-10-20 17:41:02 -0600314err:
Alex Chiangf46753c2008-06-10 15:28:50 -0600315 kfree(slot);
316 slot = ERR_PTR(err);
317 goto out;
318}
319EXPORT_SYMBOL_GPL(pci_create_slot);
320
321/**
Alex Chiangd25b7c82008-10-20 17:40:47 -0600322 * pci_renumber_slot - update %struct pci_slot -> number
Randy Dunlapcffb2fa2009-04-10 15:17:50 -0700323 * @slot: &struct pci_slot to update
324 * @slot_nr: new number for slot
Alex Chiangf46753c2008-06-10 15:28:50 -0600325 *
326 * The primary purpose of this interface is to allow callers who earlier
327 * created a placeholder slot in pci_create_slot() by passing a -1 as
328 * slot_nr, to update their %struct pci_slot with the correct @slot_nr.
329 */
Alex Chiangd25b7c82008-10-20 17:40:47 -0600330void pci_renumber_slot(struct pci_slot *slot, int slot_nr)
Alex Chiangf46753c2008-06-10 15:28:50 -0600331{
Alex Chiangf46753c2008-06-10 15:28:50 -0600332 struct pci_slot *tmp;
333
334 down_write(&pci_bus_sem);
335
336 list_for_each_entry(tmp, &slot->bus->slots, list) {
337 WARN_ON(tmp->number == slot_nr);
Alex Chiangd25b7c82008-10-20 17:40:47 -0600338 goto out;
Alex Chiangf46753c2008-06-10 15:28:50 -0600339 }
340
Alex Chiangf46753c2008-06-10 15:28:50 -0600341 slot->number = slot_nr;
Alex Chiangd25b7c82008-10-20 17:40:47 -0600342out:
Alex Chiangf46753c2008-06-10 15:28:50 -0600343 up_write(&pci_bus_sem);
344}
Alex Chiangd25b7c82008-10-20 17:40:47 -0600345EXPORT_SYMBOL_GPL(pci_renumber_slot);
Alex Chiangf46753c2008-06-10 15:28:50 -0600346
347/**
348 * pci_destroy_slot - decrement refcount for physical PCI slot
349 * @slot: struct pci_slot to decrement
350 *
351 * %struct pci_slot is refcounted, so destroying them is really easy; we
352 * just call kobject_put on its kobj and let our release methods do the
353 * rest.
354 */
Alex Chiangf46753c2008-06-10 15:28:50 -0600355void pci_destroy_slot(struct pci_slot *slot)
356{
Alex Chiang62795042009-02-04 11:25:22 -0700357 dev_dbg(&slot->bus->dev, "dev %02x, dec refcount to %d\n",
358 slot->number, atomic_read(&slot->kobj.kref.refcount) - 1);
Alex Chiangf46753c2008-06-10 15:28:50 -0600359
360 down_write(&pci_bus_sem);
361 kobject_put(&slot->kobj);
362 up_write(&pci_bus_sem);
363}
364EXPORT_SYMBOL_GPL(pci_destroy_slot);
365
Kenji Kaneshigec825bc92009-06-16 11:01:25 +0900366#if defined(CONFIG_HOTPLUG_PCI) || defined(CONFIG_HOTPLUG_PCI_MODULE)
367#include <linux/pci_hotplug.h>
368/**
369 * pci_hp_create_link - create symbolic link to the hotplug driver module.
Randy Dunlap503998c2009-06-24 09:18:14 -0700370 * @pci_slot: struct pci_slot
Kenji Kaneshigec825bc92009-06-16 11:01:25 +0900371 *
372 * Helper function for pci_hotplug_core.c to create symbolic link to
373 * the hotplug driver module.
374 */
375void pci_hp_create_module_link(struct pci_slot *pci_slot)
376{
377 struct hotplug_slot *slot = pci_slot->hotplug;
378 struct kobject *kobj = NULL;
379 int no_warn;
380
381 if (!slot || !slot->ops)
382 return;
383 kobj = kset_find_obj(module_kset, slot->ops->mod_name);
384 if (!kobj)
385 return;
386 no_warn = sysfs_create_link(&pci_slot->kobj, kobj, "module");
387 kobject_put(kobj);
388}
389EXPORT_SYMBOL_GPL(pci_hp_create_module_link);
390
391/**
392 * pci_hp_remove_link - remove symbolic link to the hotplug driver module.
Randy Dunlap503998c2009-06-24 09:18:14 -0700393 * @pci_slot: struct pci_slot
Kenji Kaneshigec825bc92009-06-16 11:01:25 +0900394 *
395 * Helper function for pci_hotplug_core.c to remove symbolic link to
396 * the hotplug driver module.
397 */
398void pci_hp_remove_module_link(struct pci_slot *pci_slot)
399{
400 sysfs_remove_link(&pci_slot->kobj, "module");
401}
402EXPORT_SYMBOL_GPL(pci_hp_remove_module_link);
403#endif
404
Alex Chiangf46753c2008-06-10 15:28:50 -0600405static int pci_slot_init(void)
406{
407 struct kset *pci_bus_kset;
408
409 pci_bus_kset = bus_get_kset(&pci_bus_type);
410 pci_slots_kset = kset_create_and_add("slots", NULL,
411 &pci_bus_kset->kobj);
412 if (!pci_slots_kset) {
413 printk(KERN_ERR "PCI: Slot initialization failure\n");
414 return -ENOMEM;
415 }
416 return 0;
417}
418
419subsys_initcall(pci_slot_init);