Elminate sparse __CHECK_ENDIAN__ warnings on port conversion
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / pci / probe.c
blob44cbbbaa499da6fc4ad886febdb5598af4993011
1 /*
2 * probe.c - PCI detection and setup code
3 */
5 #include <linux/kernel.h>
6 #include <linux/delay.h>
7 #include <linux/init.h>
8 #include <linux/pci.h>
9 #include <linux/slab.h>
10 #include <linux/module.h>
11 #include <linux/cpumask.h>
12 #include <linux/pci-aspm.h>
13 #include "pci.h"
15 #define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
16 #define CARDBUS_RESERVE_BUSNR 3
18 /* Ugh. Need to stop exporting this to modules. */
19 LIST_HEAD(pci_root_buses);
20 EXPORT_SYMBOL(pci_root_buses);
23 static int find_anything(struct device *dev, void *data)
25 return 1;
29 * Some device drivers need know if pci is initiated.
30 * Basically, we think pci is not initiated when there
31 * is no device to be found on the pci_bus_type.
33 int no_pci_devices(void)
35 struct device *dev;
36 int no_devices;
38 dev = bus_find_device(&pci_bus_type, NULL, NULL, find_anything);
39 no_devices = (dev == NULL);
40 put_device(dev);
41 return no_devices;
43 EXPORT_SYMBOL(no_pci_devices);
46 * PCI Bus Class Devices
48 static ssize_t pci_bus_show_cpuaffinity(struct device *dev,
49 int type,
50 struct device_attribute *attr,
51 char *buf)
53 int ret;
54 const struct cpumask *cpumask;
56 cpumask = cpumask_of_pcibus(to_pci_bus(dev));
57 ret = type?
58 cpulist_scnprintf(buf, PAGE_SIZE-2, cpumask) :
59 cpumask_scnprintf(buf, PAGE_SIZE-2, cpumask);
60 buf[ret++] = '\n';
61 buf[ret] = '\0';
62 return ret;
65 static ssize_t inline pci_bus_show_cpumaskaffinity(struct device *dev,
66 struct device_attribute *attr,
67 char *buf)
69 return pci_bus_show_cpuaffinity(dev, 0, attr, buf);
72 static ssize_t inline pci_bus_show_cpulistaffinity(struct device *dev,
73 struct device_attribute *attr,
74 char *buf)
76 return pci_bus_show_cpuaffinity(dev, 1, attr, buf);
79 DEVICE_ATTR(cpuaffinity, S_IRUGO, pci_bus_show_cpumaskaffinity, NULL);
80 DEVICE_ATTR(cpulistaffinity, S_IRUGO, pci_bus_show_cpulistaffinity, NULL);
83 * PCI Bus Class
85 static void release_pcibus_dev(struct device *dev)
87 struct pci_bus *pci_bus = to_pci_bus(dev);
89 if (pci_bus->bridge)
90 put_device(pci_bus->bridge);
91 pci_bus_remove_resources(pci_bus);
92 kfree(pci_bus);
95 static struct class pcibus_class = {
96 .name = "pci_bus",
97 .dev_release = &release_pcibus_dev,
100 static int __init pcibus_class_init(void)
102 return class_register(&pcibus_class);
104 postcore_initcall(pcibus_class_init);
107 * Translate the low bits of the PCI base
108 * to the resource type
110 static inline unsigned int pci_calc_resource_flags(unsigned int flags)
112 if (flags & PCI_BASE_ADDRESS_SPACE_IO)
113 return IORESOURCE_IO;
115 if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
116 return IORESOURCE_MEM | IORESOURCE_PREFETCH;
118 return IORESOURCE_MEM;
121 static u64 pci_size(u64 base, u64 maxbase, u64 mask)
123 u64 size = mask & maxbase; /* Find the significant bits */
124 if (!size)
125 return 0;
127 /* Get the lowest of them to find the decode size, and
128 from that the extent. */
129 size = (size & ~(size-1)) - 1;
131 /* base == maxbase can be valid only if the BAR has
132 already been programmed with all 1s. */
133 if (base == maxbase && ((base | size) & mask) != mask)
134 return 0;
136 return size;
139 static inline enum pci_bar_type decode_bar(struct resource *res, u32 bar)
141 if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
142 res->flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
143 return pci_bar_io;
146 res->flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
148 if (res->flags & PCI_BASE_ADDRESS_MEM_TYPE_64)
149 return pci_bar_mem64;
150 return pci_bar_mem32;
154 * pci_read_base - read a PCI BAR
155 * @dev: the PCI device
156 * @type: type of the BAR
157 * @res: resource buffer to be filled in
158 * @pos: BAR position in the config space
160 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
162 int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
163 struct resource *res, unsigned int pos)
165 u32 l, sz, mask;
166 u16 orig_cmd;
168 mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
170 if (!dev->mmio_always_on) {
171 pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
172 pci_write_config_word(dev, PCI_COMMAND,
173 orig_cmd & ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO));
176 res->name = pci_name(dev);
178 pci_read_config_dword(dev, pos, &l);
179 pci_write_config_dword(dev, pos, l | mask);
180 pci_read_config_dword(dev, pos, &sz);
181 pci_write_config_dword(dev, pos, l);
183 if (!dev->mmio_always_on)
184 pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
187 * All bits set in sz means the device isn't working properly.
188 * If the BAR isn't implemented, all bits must be 0. If it's a
189 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
190 * 1 must be clear.
192 if (!sz || sz == 0xffffffff)
193 goto fail;
196 * I don't know how l can have all bits set. Copied from old code.
197 * Maybe it fixes a bug on some ancient platform.
199 if (l == 0xffffffff)
200 l = 0;
202 if (type == pci_bar_unknown) {
203 type = decode_bar(res, l);
204 res->flags |= pci_calc_resource_flags(l) | IORESOURCE_SIZEALIGN;
205 if (type == pci_bar_io) {
206 l &= PCI_BASE_ADDRESS_IO_MASK;
207 mask = PCI_BASE_ADDRESS_IO_MASK & IO_SPACE_LIMIT;
208 } else {
209 l &= PCI_BASE_ADDRESS_MEM_MASK;
210 mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
212 } else {
213 res->flags |= (l & IORESOURCE_ROM_ENABLE);
214 l &= PCI_ROM_ADDRESS_MASK;
215 mask = (u32)PCI_ROM_ADDRESS_MASK;
218 if (type == pci_bar_mem64) {
219 u64 l64 = l;
220 u64 sz64 = sz;
221 u64 mask64 = mask | (u64)~0 << 32;
223 pci_read_config_dword(dev, pos + 4, &l);
224 pci_write_config_dword(dev, pos + 4, ~0);
225 pci_read_config_dword(dev, pos + 4, &sz);
226 pci_write_config_dword(dev, pos + 4, l);
228 l64 |= ((u64)l << 32);
229 sz64 |= ((u64)sz << 32);
231 sz64 = pci_size(l64, sz64, mask64);
233 if (!sz64)
234 goto fail;
236 if ((sizeof(resource_size_t) < 8) && (sz64 > 0x100000000ULL)) {
237 dev_err(&dev->dev, "reg %x: can't handle 64-bit BAR\n",
238 pos);
239 goto fail;
242 res->flags |= IORESOURCE_MEM_64;
243 if ((sizeof(resource_size_t) < 8) && l) {
244 /* Address above 32-bit boundary; disable the BAR */
245 pci_write_config_dword(dev, pos, 0);
246 pci_write_config_dword(dev, pos + 4, 0);
247 res->start = 0;
248 res->end = sz64;
249 } else {
250 res->start = l64;
251 res->end = l64 + sz64;
252 dev_printk(KERN_DEBUG, &dev->dev, "reg %x: %pR\n",
253 pos, res);
255 } else {
256 sz = pci_size(l, sz, mask);
258 if (!sz)
259 goto fail;
261 res->start = l;
262 res->end = l + sz;
264 dev_printk(KERN_DEBUG, &dev->dev, "reg %x: %pR\n", pos, res);
267 out:
268 return (type == pci_bar_mem64) ? 1 : 0;
269 fail:
270 res->flags = 0;
271 goto out;
274 static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
276 unsigned int pos, reg;
278 for (pos = 0; pos < howmany; pos++) {
279 struct resource *res = &dev->resource[pos];
280 reg = PCI_BASE_ADDRESS_0 + (pos << 2);
281 pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
284 if (rom) {
285 struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
286 dev->rom_base_reg = rom;
287 res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
288 IORESOURCE_READONLY | IORESOURCE_CACHEABLE |
289 IORESOURCE_SIZEALIGN;
290 __pci_read_base(dev, pci_bar_mem32, res, rom);
294 static void __devinit pci_read_bridge_io(struct pci_bus *child)
296 struct pci_dev *dev = child->self;
297 u8 io_base_lo, io_limit_lo;
298 unsigned long base, limit;
299 struct resource *res;
301 res = child->resource[0];
302 pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
303 pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
304 base = (io_base_lo & PCI_IO_RANGE_MASK) << 8;
305 limit = (io_limit_lo & PCI_IO_RANGE_MASK) << 8;
307 if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
308 u16 io_base_hi, io_limit_hi;
309 pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
310 pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
311 base |= (io_base_hi << 16);
312 limit |= (io_limit_hi << 16);
315 if (base && base <= limit) {
316 res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
317 if (!res->start)
318 res->start = base;
319 if (!res->end)
320 res->end = limit + 0xfff;
321 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
322 } else {
323 dev_printk(KERN_DEBUG, &dev->dev,
324 " bridge window [io %#06lx-%#06lx] (disabled)\n",
325 base, limit);
329 static void __devinit pci_read_bridge_mmio(struct pci_bus *child)
331 struct pci_dev *dev = child->self;
332 u16 mem_base_lo, mem_limit_lo;
333 unsigned long base, limit;
334 struct resource *res;
336 res = child->resource[1];
337 pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
338 pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
339 base = (mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
340 limit = (mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
341 if (base && base <= limit) {
342 res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
343 res->start = base;
344 res->end = limit + 0xfffff;
345 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
346 } else {
347 dev_printk(KERN_DEBUG, &dev->dev,
348 " bridge window [mem %#010lx-%#010lx] (disabled)\n",
349 base, limit + 0xfffff);
353 static void __devinit pci_read_bridge_mmio_pref(struct pci_bus *child)
355 struct pci_dev *dev = child->self;
356 u16 mem_base_lo, mem_limit_lo;
357 unsigned long base, limit;
358 struct resource *res;
360 res = child->resource[2];
361 pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
362 pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
363 base = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
364 limit = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
366 if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
367 u32 mem_base_hi, mem_limit_hi;
368 pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
369 pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
372 * Some bridges set the base > limit by default, and some
373 * (broken) BIOSes do not initialize them. If we find
374 * this, just assume they are not being used.
376 if (mem_base_hi <= mem_limit_hi) {
377 #if BITS_PER_LONG == 64
378 base |= ((long) mem_base_hi) << 32;
379 limit |= ((long) mem_limit_hi) << 32;
380 #else
381 if (mem_base_hi || mem_limit_hi) {
382 dev_err(&dev->dev, "can't handle 64-bit "
383 "address space for bridge\n");
384 return;
386 #endif
389 if (base && base <= limit) {
390 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
391 IORESOURCE_MEM | IORESOURCE_PREFETCH;
392 if (res->flags & PCI_PREF_RANGE_TYPE_64)
393 res->flags |= IORESOURCE_MEM_64;
394 res->start = base;
395 res->end = limit + 0xfffff;
396 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
397 } else {
398 dev_printk(KERN_DEBUG, &dev->dev,
399 " bridge window [mem %#010lx-%#010lx pref] (disabled)\n",
400 base, limit + 0xfffff);
404 void __devinit pci_read_bridge_bases(struct pci_bus *child)
406 struct pci_dev *dev = child->self;
407 struct resource *res;
408 int i;
410 if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
411 return;
413 dev_info(&dev->dev, "PCI bridge to [bus %02x-%02x]%s\n",
414 child->secondary, child->subordinate,
415 dev->transparent ? " (subtractive decode)" : "");
417 pci_bus_remove_resources(child);
418 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
419 child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
421 pci_read_bridge_io(child);
422 pci_read_bridge_mmio(child);
423 pci_read_bridge_mmio_pref(child);
425 if (dev->transparent) {
426 pci_bus_for_each_resource(child->parent, res, i) {
427 if (res) {
428 pci_bus_add_resource(child, res,
429 PCI_SUBTRACTIVE_DECODE);
430 dev_printk(KERN_DEBUG, &dev->dev,
431 " bridge window %pR (subtractive decode)\n",
432 res);
438 static struct pci_bus * pci_alloc_bus(void)
440 struct pci_bus *b;
442 b = kzalloc(sizeof(*b), GFP_KERNEL);
443 if (b) {
444 INIT_LIST_HEAD(&b->node);
445 INIT_LIST_HEAD(&b->children);
446 INIT_LIST_HEAD(&b->devices);
447 INIT_LIST_HEAD(&b->slots);
448 INIT_LIST_HEAD(&b->resources);
449 b->max_bus_speed = PCI_SPEED_UNKNOWN;
450 b->cur_bus_speed = PCI_SPEED_UNKNOWN;
452 return b;
455 static unsigned char pcix_bus_speed[] = {
456 PCI_SPEED_UNKNOWN, /* 0 */
457 PCI_SPEED_66MHz_PCIX, /* 1 */
458 PCI_SPEED_100MHz_PCIX, /* 2 */
459 PCI_SPEED_133MHz_PCIX, /* 3 */
460 PCI_SPEED_UNKNOWN, /* 4 */
461 PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
462 PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
463 PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
464 PCI_SPEED_UNKNOWN, /* 8 */
465 PCI_SPEED_66MHz_PCIX_266, /* 9 */
466 PCI_SPEED_100MHz_PCIX_266, /* A */
467 PCI_SPEED_133MHz_PCIX_266, /* B */
468 PCI_SPEED_UNKNOWN, /* C */
469 PCI_SPEED_66MHz_PCIX_533, /* D */
470 PCI_SPEED_100MHz_PCIX_533, /* E */
471 PCI_SPEED_133MHz_PCIX_533 /* F */
474 static unsigned char pcie_link_speed[] = {
475 PCI_SPEED_UNKNOWN, /* 0 */
476 PCIE_SPEED_2_5GT, /* 1 */
477 PCIE_SPEED_5_0GT, /* 2 */
478 PCIE_SPEED_8_0GT, /* 3 */
479 PCI_SPEED_UNKNOWN, /* 4 */
480 PCI_SPEED_UNKNOWN, /* 5 */
481 PCI_SPEED_UNKNOWN, /* 6 */
482 PCI_SPEED_UNKNOWN, /* 7 */
483 PCI_SPEED_UNKNOWN, /* 8 */
484 PCI_SPEED_UNKNOWN, /* 9 */
485 PCI_SPEED_UNKNOWN, /* A */
486 PCI_SPEED_UNKNOWN, /* B */
487 PCI_SPEED_UNKNOWN, /* C */
488 PCI_SPEED_UNKNOWN, /* D */
489 PCI_SPEED_UNKNOWN, /* E */
490 PCI_SPEED_UNKNOWN /* F */
493 void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
495 bus->cur_bus_speed = pcie_link_speed[linksta & 0xf];
497 EXPORT_SYMBOL_GPL(pcie_update_link_speed);
499 static unsigned char agp_speeds[] = {
500 AGP_UNKNOWN,
501 AGP_1X,
502 AGP_2X,
503 AGP_4X,
504 AGP_8X
507 static enum pci_bus_speed agp_speed(int agp3, int agpstat)
509 int index = 0;
511 if (agpstat & 4)
512 index = 3;
513 else if (agpstat & 2)
514 index = 2;
515 else if (agpstat & 1)
516 index = 1;
517 else
518 goto out;
520 if (agp3) {
521 index += 2;
522 if (index == 5)
523 index = 0;
526 out:
527 return agp_speeds[index];
531 static void pci_set_bus_speed(struct pci_bus *bus)
533 struct pci_dev *bridge = bus->self;
534 int pos;
536 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
537 if (!pos)
538 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
539 if (pos) {
540 u32 agpstat, agpcmd;
542 pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
543 bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
545 pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
546 bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
549 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
550 if (pos) {
551 u16 status;
552 enum pci_bus_speed max;
553 pci_read_config_word(bridge, pos + 2, &status);
555 if (status & 0x8000) {
556 max = PCI_SPEED_133MHz_PCIX_533;
557 } else if (status & 0x4000) {
558 max = PCI_SPEED_133MHz_PCIX_266;
559 } else if (status & 0x0002) {
560 if (((status >> 12) & 0x3) == 2) {
561 max = PCI_SPEED_133MHz_PCIX_ECC;
562 } else {
563 max = PCI_SPEED_133MHz_PCIX;
565 } else {
566 max = PCI_SPEED_66MHz_PCIX;
569 bus->max_bus_speed = max;
570 bus->cur_bus_speed = pcix_bus_speed[(status >> 6) & 0xf];
572 return;
575 pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
576 if (pos) {
577 u32 linkcap;
578 u16 linksta;
580 pci_read_config_dword(bridge, pos + PCI_EXP_LNKCAP, &linkcap);
581 bus->max_bus_speed = pcie_link_speed[linkcap & 0xf];
583 pci_read_config_word(bridge, pos + PCI_EXP_LNKSTA, &linksta);
584 pcie_update_link_speed(bus, linksta);
589 static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
590 struct pci_dev *bridge, int busnr)
592 struct pci_bus *child;
593 int i;
596 * Allocate a new bus, and inherit stuff from the parent..
598 child = pci_alloc_bus();
599 if (!child)
600 return NULL;
602 child->parent = parent;
603 child->ops = parent->ops;
604 child->sysdata = parent->sysdata;
605 child->bus_flags = parent->bus_flags;
607 /* initialize some portions of the bus device, but don't register it
608 * now as the parent is not properly set up yet. This device will get
609 * registered later in pci_bus_add_devices()
611 child->dev.class = &pcibus_class;
612 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
615 * Set up the primary, secondary and subordinate
616 * bus numbers.
618 child->number = child->secondary = busnr;
619 child->primary = parent->secondary;
620 child->subordinate = 0xff;
622 if (!bridge)
623 return child;
625 child->self = bridge;
626 child->bridge = get_device(&bridge->dev);
628 pci_set_bus_speed(child);
630 /* Set up default resource pointers and names.. */
631 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
632 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
633 child->resource[i]->name = child->name;
635 bridge->subordinate = child;
637 return child;
640 struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr)
642 struct pci_bus *child;
644 child = pci_alloc_child_bus(parent, dev, busnr);
645 if (child) {
646 down_write(&pci_bus_sem);
647 list_add_tail(&child->node, &parent->children);
648 up_write(&pci_bus_sem);
650 return child;
653 static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
655 struct pci_bus *parent = child->parent;
657 /* Attempts to fix that up are really dangerous unless
658 we're going to re-assign all bus numbers. */
659 if (!pcibios_assign_all_busses())
660 return;
662 while (parent->parent && parent->subordinate < max) {
663 parent->subordinate = max;
664 pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);
665 parent = parent->parent;
670 * If it's a bridge, configure it and scan the bus behind it.
671 * For CardBus bridges, we don't scan behind as the devices will
672 * be handled by the bridge driver itself.
674 * We need to process bridges in two passes -- first we scan those
675 * already configured by the BIOS and after we are done with all of
676 * them, we proceed to assigning numbers to the remaining buses in
677 * order to avoid overlaps between old and new bus numbers.
679 int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
681 struct pci_bus *child;
682 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
683 u32 buses, i, j = 0;
684 u16 bctl;
685 u8 primary, secondary, subordinate;
686 int broken = 0;
688 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
689 primary = buses & 0xFF;
690 secondary = (buses >> 8) & 0xFF;
691 subordinate = (buses >> 16) & 0xFF;
693 dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
694 secondary, subordinate, pass);
696 /* Check if setup is sensible at all */
697 if (!pass &&
698 (primary != bus->number || secondary <= bus->number)) {
699 dev_dbg(&dev->dev, "bus configuration invalid, reconfiguring\n");
700 broken = 1;
703 /* Disable MasterAbortMode during probing to avoid reporting
704 of bus errors (in some architectures) */
705 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
706 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
707 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
709 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
710 !is_cardbus && !broken) {
711 unsigned int cmax;
713 * Bus already configured by firmware, process it in the first
714 * pass and just note the configuration.
716 if (pass)
717 goto out;
720 * If we already got to this bus through a different bridge,
721 * don't re-add it. This can happen with the i450NX chipset.
723 * However, we continue to descend down the hierarchy and
724 * scan remaining child buses.
726 child = pci_find_bus(pci_domain_nr(bus), secondary);
727 if (!child) {
728 child = pci_add_new_bus(bus, dev, secondary);
729 if (!child)
730 goto out;
731 child->primary = primary;
732 child->subordinate = subordinate;
733 child->bridge_ctl = bctl;
736 cmax = pci_scan_child_bus(child);
737 if (cmax > max)
738 max = cmax;
739 if (child->subordinate > max)
740 max = child->subordinate;
741 } else {
743 * We need to assign a number to this bus which we always
744 * do in the second pass.
746 if (!pass) {
747 if (pcibios_assign_all_busses() || broken)
748 /* Temporarily disable forwarding of the
749 configuration cycles on all bridges in
750 this bus segment to avoid possible
751 conflicts in the second pass between two
752 bridges programmed with overlapping
753 bus ranges. */
754 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
755 buses & ~0xffffff);
756 goto out;
759 /* Clear errors */
760 pci_write_config_word(dev, PCI_STATUS, 0xffff);
762 /* Prevent assigning a bus number that already exists.
763 * This can happen when a bridge is hot-plugged */
764 if (pci_find_bus(pci_domain_nr(bus), max+1))
765 goto out;
766 child = pci_add_new_bus(bus, dev, ++max);
767 if (!child)
768 goto out;
769 buses = (buses & 0xff000000)
770 | ((unsigned int)(child->primary) << 0)
771 | ((unsigned int)(child->secondary) << 8)
772 | ((unsigned int)(child->subordinate) << 16);
775 * yenta.c forces a secondary latency timer of 176.
776 * Copy that behaviour here.
778 if (is_cardbus) {
779 buses &= ~0xff000000;
780 buses |= CARDBUS_LATENCY_TIMER << 24;
784 * We need to blast all three values with a single write.
786 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
788 if (!is_cardbus) {
789 child->bridge_ctl = bctl;
791 * Adjust subordinate busnr in parent buses.
792 * We do this before scanning for children because
793 * some devices may not be detected if the bios
794 * was lazy.
796 pci_fixup_parent_subordinate_busnr(child, max);
797 /* Now we can scan all subordinate buses... */
798 max = pci_scan_child_bus(child);
800 * now fix it up again since we have found
801 * the real value of max.
803 pci_fixup_parent_subordinate_busnr(child, max);
804 } else {
806 * For CardBus bridges, we leave 4 bus numbers
807 * as cards with a PCI-to-PCI bridge can be
808 * inserted later.
810 for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
811 struct pci_bus *parent = bus;
812 if (pci_find_bus(pci_domain_nr(bus),
813 max+i+1))
814 break;
815 while (parent->parent) {
816 if ((!pcibios_assign_all_busses()) &&
817 (parent->subordinate > max) &&
818 (parent->subordinate <= max+i)) {
819 j = 1;
821 parent = parent->parent;
823 if (j) {
825 * Often, there are two cardbus bridges
826 * -- try to leave one valid bus number
827 * for each one.
829 i /= 2;
830 break;
833 max += i;
834 pci_fixup_parent_subordinate_busnr(child, max);
837 * Set the subordinate bus number to its real value.
839 child->subordinate = max;
840 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
843 sprintf(child->name,
844 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
845 pci_domain_nr(bus), child->number);
847 /* Has only triggered on CardBus, fixup is in yenta_socket */
848 while (bus->parent) {
849 if ((child->subordinate > bus->subordinate) ||
850 (child->number > bus->subordinate) ||
851 (child->number < bus->number) ||
852 (child->subordinate < bus->number)) {
853 dev_info(&child->dev, "[bus %02x-%02x] %s "
854 "hidden behind%s bridge %s [bus %02x-%02x]\n",
855 child->number, child->subordinate,
856 (bus->number > child->subordinate &&
857 bus->subordinate < child->number) ?
858 "wholly" : "partially",
859 bus->self->transparent ? " transparent" : "",
860 dev_name(&bus->dev),
861 bus->number, bus->subordinate);
863 bus = bus->parent;
866 out:
867 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
869 return max;
873 * Read interrupt line and base address registers.
874 * The architecture-dependent code can tweak these, of course.
876 static void pci_read_irq(struct pci_dev *dev)
878 unsigned char irq;
880 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
881 dev->pin = irq;
882 if (irq)
883 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
884 dev->irq = irq;
887 void set_pcie_port_type(struct pci_dev *pdev)
889 int pos;
890 u16 reg16;
892 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
893 if (!pos)
894 return;
895 pdev->is_pcie = 1;
896 pdev->pcie_cap = pos;
897 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, &reg16);
898 pdev->pcie_type = (reg16 & PCI_EXP_FLAGS_TYPE) >> 4;
901 void set_pcie_hotplug_bridge(struct pci_dev *pdev)
903 int pos;
904 u16 reg16;
905 u32 reg32;
907 pos = pci_pcie_cap(pdev);
908 if (!pos)
909 return;
910 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, &reg16);
911 if (!(reg16 & PCI_EXP_FLAGS_SLOT))
912 return;
913 pci_read_config_dword(pdev, pos + PCI_EXP_SLTCAP, &reg32);
914 if (reg32 & PCI_EXP_SLTCAP_HPC)
915 pdev->is_hotplug_bridge = 1;
918 #define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
921 * pci_setup_device - fill in class and map information of a device
922 * @dev: the device structure to fill
924 * Initialize the device structure with information about the device's
925 * vendor,class,memory and IO-space addresses,IRQ lines etc.
926 * Called at initialisation of the PCI subsystem and by CardBus services.
927 * Returns 0 on success and negative if unknown type of device (not normal,
928 * bridge or CardBus).
930 int pci_setup_device(struct pci_dev *dev)
932 u32 class;
933 u8 hdr_type;
934 struct pci_slot *slot;
935 int pos = 0;
937 if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
938 return -EIO;
940 dev->sysdata = dev->bus->sysdata;
941 dev->dev.parent = dev->bus->bridge;
942 dev->dev.bus = &pci_bus_type;
943 dev->hdr_type = hdr_type & 0x7f;
944 dev->multifunction = !!(hdr_type & 0x80);
945 dev->error_state = pci_channel_io_normal;
946 set_pcie_port_type(dev);
948 list_for_each_entry(slot, &dev->bus->slots, list)
949 if (PCI_SLOT(dev->devfn) == slot->number)
950 dev->slot = slot;
952 /* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
953 set this higher, assuming the system even supports it. */
954 dev->dma_mask = 0xffffffff;
956 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
957 dev->bus->number, PCI_SLOT(dev->devfn),
958 PCI_FUNC(dev->devfn));
960 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
961 dev->revision = class & 0xff;
962 class >>= 8; /* upper 3 bytes */
963 dev->class = class;
964 class >>= 8;
966 dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %d class %#08x\n",
967 dev->vendor, dev->device, dev->hdr_type, class);
969 /* need to have dev->class ready */
970 dev->cfg_size = pci_cfg_space_size(dev);
972 /* "Unknown power state" */
973 dev->current_state = PCI_UNKNOWN;
975 /* Early fixups, before probing the BARs */
976 pci_fixup_device(pci_fixup_early, dev);
977 /* device class may be changed after fixup */
978 class = dev->class >> 8;
980 switch (dev->hdr_type) { /* header type */
981 case PCI_HEADER_TYPE_NORMAL: /* standard header */
982 if (class == PCI_CLASS_BRIDGE_PCI)
983 goto bad;
984 pci_read_irq(dev);
985 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
986 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
987 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
990 * Do the ugly legacy mode stuff here rather than broken chip
991 * quirk code. Legacy mode ATA controllers have fixed
992 * addresses. These are not always echoed in BAR0-3, and
993 * BAR0-3 in a few cases contain junk!
995 if (class == PCI_CLASS_STORAGE_IDE) {
996 u8 progif;
997 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
998 if ((progif & 1) == 0) {
999 dev->resource[0].start = 0x1F0;
1000 dev->resource[0].end = 0x1F7;
1001 dev->resource[0].flags = LEGACY_IO_RESOURCE;
1002 dev->resource[1].start = 0x3F6;
1003 dev->resource[1].end = 0x3F6;
1004 dev->resource[1].flags = LEGACY_IO_RESOURCE;
1006 if ((progif & 4) == 0) {
1007 dev->resource[2].start = 0x170;
1008 dev->resource[2].end = 0x177;
1009 dev->resource[2].flags = LEGACY_IO_RESOURCE;
1010 dev->resource[3].start = 0x376;
1011 dev->resource[3].end = 0x376;
1012 dev->resource[3].flags = LEGACY_IO_RESOURCE;
1015 break;
1017 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1018 if (class != PCI_CLASS_BRIDGE_PCI)
1019 goto bad;
1020 /* The PCI-to-PCI bridge spec requires that subtractive
1021 decoding (i.e. transparent) bridge must have programming
1022 interface code of 0x01. */
1023 pci_read_irq(dev);
1024 dev->transparent = ((dev->class & 0xff) == 1);
1025 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1026 set_pcie_hotplug_bridge(dev);
1027 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1028 if (pos) {
1029 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1030 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1032 break;
1034 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1035 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1036 goto bad;
1037 pci_read_irq(dev);
1038 pci_read_bases(dev, 1, 0);
1039 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1040 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1041 break;
1043 default: /* unknown header */
1044 dev_err(&dev->dev, "unknown header type %02x, "
1045 "ignoring device\n", dev->hdr_type);
1046 return -EIO;
1048 bad:
1049 dev_err(&dev->dev, "ignoring class %02x (doesn't match header "
1050 "type %02x)\n", class, dev->hdr_type);
1051 dev->class = PCI_CLASS_NOT_DEFINED;
1054 /* We found a fine healthy device, go go go... */
1055 return 0;
1058 static void pci_release_capabilities(struct pci_dev *dev)
1060 pci_vpd_release(dev);
1061 pci_iov_release(dev);
1065 * pci_release_dev - free a pci device structure when all users of it are finished.
1066 * @dev: device that's been disconnected
1068 * Will be called only by the device core when all users of this pci device are
1069 * done.
1071 static void pci_release_dev(struct device *dev)
1073 struct pci_dev *pci_dev;
1075 pci_dev = to_pci_dev(dev);
1076 pci_release_capabilities(pci_dev);
1077 kfree(pci_dev);
1081 * pci_cfg_space_size - get the configuration space size of the PCI device.
1082 * @dev: PCI device
1084 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1085 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1086 * access it. Maybe we don't have a way to generate extended config space
1087 * accesses, or the device is behind a reverse Express bridge. So we try
1088 * reading the dword at 0x100 which must either be 0 or a valid extended
1089 * capability header.
1091 int pci_cfg_space_size_ext(struct pci_dev *dev)
1093 u32 status;
1094 int pos = PCI_CFG_SPACE_SIZE;
1096 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1097 goto fail;
1098 if (status == 0xffffffff)
1099 goto fail;
1101 return PCI_CFG_SPACE_EXP_SIZE;
1103 fail:
1104 return PCI_CFG_SPACE_SIZE;
1107 int pci_cfg_space_size(struct pci_dev *dev)
1109 int pos;
1110 u32 status;
1111 u16 class;
1113 class = dev->class >> 8;
1114 if (class == PCI_CLASS_BRIDGE_HOST)
1115 return pci_cfg_space_size_ext(dev);
1117 pos = pci_pcie_cap(dev);
1118 if (!pos) {
1119 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1120 if (!pos)
1121 goto fail;
1123 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1124 if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
1125 goto fail;
1128 return pci_cfg_space_size_ext(dev);
1130 fail:
1131 return PCI_CFG_SPACE_SIZE;
1134 static void pci_release_bus_bridge_dev(struct device *dev)
1136 kfree(dev);
1139 struct pci_dev *alloc_pci_dev(void)
1141 struct pci_dev *dev;
1143 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
1144 if (!dev)
1145 return NULL;
1147 INIT_LIST_HEAD(&dev->bus_list);
1149 return dev;
1151 EXPORT_SYMBOL(alloc_pci_dev);
1154 * Read the config data for a PCI device, sanity-check it
1155 * and fill in the dev structure...
1157 static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
1159 struct pci_dev *dev;
1160 u32 l;
1161 int delay = 1;
1163 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, &l))
1164 return NULL;
1166 /* some broken boards return 0 or ~0 if a slot is empty: */
1167 if (l == 0xffffffff || l == 0x00000000 ||
1168 l == 0x0000ffff || l == 0xffff0000)
1169 return NULL;
1171 /* Configuration request Retry Status */
1172 while (l == 0xffff0001) {
1173 msleep(delay);
1174 delay *= 2;
1175 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, &l))
1176 return NULL;
1177 /* Card hasn't responded in 60 seconds? Must be stuck. */
1178 if (delay > 60 * 1000) {
1179 printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not "
1180 "responding\n", pci_domain_nr(bus),
1181 bus->number, PCI_SLOT(devfn),
1182 PCI_FUNC(devfn));
1183 return NULL;
1187 dev = alloc_pci_dev();
1188 if (!dev)
1189 return NULL;
1191 dev->bus = bus;
1192 dev->devfn = devfn;
1193 dev->vendor = l & 0xffff;
1194 dev->device = (l >> 16) & 0xffff;
1196 if (pci_setup_device(dev)) {
1197 kfree(dev);
1198 return NULL;
1201 return dev;
1204 static void pci_init_capabilities(struct pci_dev *dev)
1206 /* MSI/MSI-X list */
1207 pci_msi_init_pci_dev(dev);
1209 /* Buffers for saving PCIe and PCI-X capabilities */
1210 pci_allocate_cap_save_buffers(dev);
1212 /* Power Management */
1213 pci_pm_init(dev);
1214 platform_pci_wakeup_init(dev);
1216 /* Vital Product Data */
1217 pci_vpd_pci22_init(dev);
1219 /* Alternative Routing-ID Forwarding */
1220 pci_enable_ari(dev);
1222 /* Single Root I/O Virtualization */
1223 pci_iov_init(dev);
1225 /* Enable ACS P2P upstream forwarding */
1226 pci_enable_acs(dev);
1229 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
1231 device_initialize(&dev->dev);
1232 dev->dev.release = pci_release_dev;
1233 pci_dev_get(dev);
1235 dev->dev.dma_mask = &dev->dma_mask;
1236 dev->dev.dma_parms = &dev->dma_parms;
1237 dev->dev.coherent_dma_mask = 0xffffffffull;
1239 pci_set_dma_max_seg_size(dev, 65536);
1240 pci_set_dma_seg_boundary(dev, 0xffffffff);
1242 /* Fix up broken headers */
1243 pci_fixup_device(pci_fixup_header, dev);
1245 /* Clear the state_saved flag. */
1246 dev->state_saved = false;
1248 /* Initialize various capabilities */
1249 pci_init_capabilities(dev);
1252 * Add the device to our list of discovered devices
1253 * and the bus list for fixup functions, etc.
1255 down_write(&pci_bus_sem);
1256 list_add_tail(&dev->bus_list, &bus->devices);
1257 up_write(&pci_bus_sem);
1260 struct pci_dev *__ref pci_scan_single_device(struct pci_bus *bus, int devfn)
1262 struct pci_dev *dev;
1264 dev = pci_get_slot(bus, devfn);
1265 if (dev) {
1266 pci_dev_put(dev);
1267 return dev;
1270 dev = pci_scan_device(bus, devfn);
1271 if (!dev)
1272 return NULL;
1274 pci_device_add(dev, bus);
1276 return dev;
1278 EXPORT_SYMBOL(pci_scan_single_device);
1280 static unsigned next_ari_fn(struct pci_dev *dev, unsigned fn)
1282 u16 cap;
1283 unsigned pos, next_fn;
1285 if (!dev)
1286 return 0;
1288 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1289 if (!pos)
1290 return 0;
1291 pci_read_config_word(dev, pos + 4, &cap);
1292 next_fn = cap >> 8;
1293 if (next_fn <= fn)
1294 return 0;
1295 return next_fn;
1298 static unsigned next_trad_fn(struct pci_dev *dev, unsigned fn)
1300 return (fn + 1) % 8;
1303 static unsigned no_next_fn(struct pci_dev *dev, unsigned fn)
1305 return 0;
1308 static int only_one_child(struct pci_bus *bus)
1310 struct pci_dev *parent = bus->self;
1311 if (!parent || !pci_is_pcie(parent))
1312 return 0;
1313 if (parent->pcie_type == PCI_EXP_TYPE_ROOT_PORT ||
1314 parent->pcie_type == PCI_EXP_TYPE_DOWNSTREAM)
1315 return 1;
1316 return 0;
1320 * pci_scan_slot - scan a PCI slot on a bus for devices.
1321 * @bus: PCI bus to scan
1322 * @devfn: slot number to scan (must have zero function.)
1324 * Scan a PCI slot on the specified PCI bus for devices, adding
1325 * discovered devices to the @bus->devices list. New devices
1326 * will not have is_added set.
1328 * Returns the number of new devices found.
1330 int pci_scan_slot(struct pci_bus *bus, int devfn)
1332 unsigned fn, nr = 0;
1333 struct pci_dev *dev;
1334 unsigned (*next_fn)(struct pci_dev *, unsigned) = no_next_fn;
1336 if (only_one_child(bus) && (devfn > 0))
1337 return 0; /* Already scanned the entire slot */
1339 dev = pci_scan_single_device(bus, devfn);
1340 if (!dev)
1341 return 0;
1342 if (!dev->is_added)
1343 nr++;
1345 if (pci_ari_enabled(bus))
1346 next_fn = next_ari_fn;
1347 else if (dev->multifunction)
1348 next_fn = next_trad_fn;
1350 for (fn = next_fn(dev, 0); fn > 0; fn = next_fn(dev, fn)) {
1351 dev = pci_scan_single_device(bus, devfn + fn);
1352 if (dev) {
1353 if (!dev->is_added)
1354 nr++;
1355 dev->multifunction = 1;
1359 /* only one slot has pcie device */
1360 if (bus->self && nr)
1361 pcie_aspm_init_link_state(bus->self);
1363 return nr;
1366 unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
1368 unsigned int devfn, pass, max = bus->secondary;
1369 struct pci_dev *dev;
1371 dev_dbg(&bus->dev, "scanning bus\n");
1373 /* Go find them, Rover! */
1374 for (devfn = 0; devfn < 0x100; devfn += 8)
1375 pci_scan_slot(bus, devfn);
1377 /* Reserve buses for SR-IOV capability. */
1378 max += pci_iov_bus_range(bus);
1381 * After performing arch-dependent fixup of the bus, look behind
1382 * all PCI-to-PCI bridges on this bus.
1384 if (!bus->is_added) {
1385 dev_dbg(&bus->dev, "fixups for bus\n");
1386 pcibios_fixup_bus(bus);
1387 if (pci_is_root_bus(bus))
1388 bus->is_added = 1;
1391 for (pass=0; pass < 2; pass++)
1392 list_for_each_entry(dev, &bus->devices, bus_list) {
1393 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
1394 dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
1395 max = pci_scan_bridge(bus, dev, max, pass);
1399 * We've scanned the bus and so we know all about what's on
1400 * the other side of any bridges that may be on this bus plus
1401 * any devices.
1403 * Return how far we've got finding sub-buses.
1405 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
1406 return max;
1409 struct pci_bus * pci_create_bus(struct device *parent,
1410 int bus, struct pci_ops *ops, void *sysdata)
1412 int error;
1413 struct pci_bus *b, *b2;
1414 struct device *dev;
1416 b = pci_alloc_bus();
1417 if (!b)
1418 return NULL;
1420 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1421 if (!dev){
1422 kfree(b);
1423 return NULL;
1426 b->sysdata = sysdata;
1427 b->ops = ops;
1429 b2 = pci_find_bus(pci_domain_nr(b), bus);
1430 if (b2) {
1431 /* If we already got to this bus through a different bridge, ignore it */
1432 dev_dbg(&b2->dev, "bus already known\n");
1433 goto err_out;
1436 down_write(&pci_bus_sem);
1437 list_add_tail(&b->node, &pci_root_buses);
1438 up_write(&pci_bus_sem);
1440 dev->parent = parent;
1441 dev->release = pci_release_bus_bridge_dev;
1442 dev_set_name(dev, "pci%04x:%02x", pci_domain_nr(b), bus);
1443 error = device_register(dev);
1444 if (error)
1445 goto dev_reg_err;
1446 b->bridge = get_device(dev);
1447 device_enable_async_suspend(b->bridge);
1449 if (!parent)
1450 set_dev_node(b->bridge, pcibus_to_node(b));
1452 b->dev.class = &pcibus_class;
1453 b->dev.parent = b->bridge;
1454 dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
1455 error = device_register(&b->dev);
1456 if (error)
1457 goto class_dev_reg_err;
1458 error = device_create_file(&b->dev, &dev_attr_cpuaffinity);
1459 if (error)
1460 goto dev_create_file_err;
1462 /* Create legacy_io and legacy_mem files for this bus */
1463 pci_create_legacy_files(b);
1465 b->number = b->secondary = bus;
1466 b->resource[0] = &ioport_resource;
1467 b->resource[1] = &iomem_resource;
1469 return b;
1471 dev_create_file_err:
1472 device_unregister(&b->dev);
1473 class_dev_reg_err:
1474 device_unregister(dev);
1475 dev_reg_err:
1476 down_write(&pci_bus_sem);
1477 list_del(&b->node);
1478 up_write(&pci_bus_sem);
1479 err_out:
1480 kfree(dev);
1481 kfree(b);
1482 return NULL;
1485 struct pci_bus * __devinit pci_scan_bus_parented(struct device *parent,
1486 int bus, struct pci_ops *ops, void *sysdata)
1488 struct pci_bus *b;
1490 b = pci_create_bus(parent, bus, ops, sysdata);
1491 if (b)
1492 b->subordinate = pci_scan_child_bus(b);
1493 return b;
1495 EXPORT_SYMBOL(pci_scan_bus_parented);
1497 #ifdef CONFIG_HOTPLUG
1499 * pci_rescan_bus - scan a PCI bus for devices.
1500 * @bus: PCI bus to scan
1502 * Scan a PCI bus and child buses for new devices, adds them,
1503 * and enables them.
1505 * Returns the max number of subordinate bus discovered.
1507 unsigned int __ref pci_rescan_bus(struct pci_bus *bus)
1509 unsigned int max;
1510 struct pci_dev *dev;
1512 max = pci_scan_child_bus(bus);
1514 down_read(&pci_bus_sem);
1515 list_for_each_entry(dev, &bus->devices, bus_list)
1516 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
1517 dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
1518 if (dev->subordinate)
1519 pci_bus_size_bridges(dev->subordinate);
1520 up_read(&pci_bus_sem);
1522 pci_bus_assign_resources(bus);
1523 pci_enable_bridges(bus);
1524 pci_bus_add_devices(bus);
1526 return max;
1528 EXPORT_SYMBOL_GPL(pci_rescan_bus);
1530 EXPORT_SYMBOL(pci_add_new_bus);
1531 EXPORT_SYMBOL(pci_scan_slot);
1532 EXPORT_SYMBOL(pci_scan_bridge);
1533 EXPORT_SYMBOL_GPL(pci_scan_child_bus);
1534 #endif
1536 static int __init pci_sort_bf_cmp(const struct device *d_a, const struct device *d_b)
1538 const struct pci_dev *a = to_pci_dev(d_a);
1539 const struct pci_dev *b = to_pci_dev(d_b);
1541 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
1542 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
1544 if (a->bus->number < b->bus->number) return -1;
1545 else if (a->bus->number > b->bus->number) return 1;
1547 if (a->devfn < b->devfn) return -1;
1548 else if (a->devfn > b->devfn) return 1;
1550 return 0;
1553 void __init pci_sort_breadthfirst(void)
1555 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);