2 * probe.c - PCI detection and setup code
5 #include <linux/kernel.h>
6 #include <linux/delay.h>
7 #include <linux/init.h>
9 #include <linux/slab.h>
10 #include <linux/module.h>
11 #include <linux/cpumask.h>
12 #include <linux/pci-aspm.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)
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)
38 dev = bus_find_device(&pci_bus_type, NULL, NULL, find_anything);
39 no_devices = (dev == NULL);
43 EXPORT_SYMBOL(no_pci_devices);
48 static void release_pcibus_dev(struct device *dev)
50 struct pci_bus *pci_bus = to_pci_bus(dev);
53 put_device(pci_bus->bridge);
54 pci_bus_remove_resources(pci_bus);
55 pci_release_bus_of_node(pci_bus);
59 static struct class pcibus_class = {
61 .dev_release = &release_pcibus_dev,
62 .dev_attrs = pcibus_dev_attrs,
65 static int __init pcibus_class_init(void)
67 return class_register(&pcibus_class);
69 postcore_initcall(pcibus_class_init);
71 static u64 pci_size(u64 base, u64 maxbase, u64 mask)
73 u64 size = mask & maxbase; /* Find the significant bits */
77 /* Get the lowest of them to find the decode size, and
78 from that the extent. */
79 size = (size & ~(size-1)) - 1;
81 /* base == maxbase can be valid only if the BAR has
82 already been programmed with all 1s. */
83 if (base == maxbase && ((base | size) & mask) != mask)
89 static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
94 if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
95 flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
96 flags |= IORESOURCE_IO;
100 flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
101 flags |= IORESOURCE_MEM;
102 if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
103 flags |= IORESOURCE_PREFETCH;
105 mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
107 case PCI_BASE_ADDRESS_MEM_TYPE_32:
109 case PCI_BASE_ADDRESS_MEM_TYPE_1M:
110 dev_info(&dev->dev, "1M mem BAR treated as 32-bit BAR\n");
112 case PCI_BASE_ADDRESS_MEM_TYPE_64:
113 flags |= IORESOURCE_MEM_64;
117 "mem unknown type %x treated as 32-bit BAR\n",
125 * pci_read_base - read a PCI BAR
126 * @dev: the PCI device
127 * @type: type of the BAR
128 * @res: resource buffer to be filled in
129 * @pos: BAR position in the config space
131 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
133 int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
134 struct resource *res, unsigned int pos)
139 mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
141 if (!dev->mmio_always_on) {
142 pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
143 pci_write_config_word(dev, PCI_COMMAND,
144 orig_cmd & ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO));
147 res->name = pci_name(dev);
149 pci_read_config_dword(dev, pos, &l);
150 pci_write_config_dword(dev, pos, l | mask);
151 pci_read_config_dword(dev, pos, &sz);
152 pci_write_config_dword(dev, pos, l);
154 if (!dev->mmio_always_on)
155 pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
158 * All bits set in sz means the device isn't working properly.
159 * If the BAR isn't implemented, all bits must be 0. If it's a
160 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
163 if (!sz || sz == 0xffffffff)
167 * I don't know how l can have all bits set. Copied from old code.
168 * Maybe it fixes a bug on some ancient platform.
173 if (type == pci_bar_unknown) {
174 res->flags = decode_bar(dev, l);
175 res->flags |= IORESOURCE_SIZEALIGN;
176 if (res->flags & IORESOURCE_IO) {
177 l &= PCI_BASE_ADDRESS_IO_MASK;
178 sz &= PCI_BASE_ADDRESS_IO_MASK;
179 mask = PCI_BASE_ADDRESS_IO_MASK & (u32) IO_SPACE_LIMIT;
181 l &= PCI_BASE_ADDRESS_MEM_MASK;
182 sz &= PCI_BASE_ADDRESS_MEM_MASK;
183 mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
186 res->flags |= (l & IORESOURCE_ROM_ENABLE);
187 l &= PCI_ROM_ADDRESS_MASK;
188 sz &= PCI_ROM_ADDRESS_MASK;
189 mask = (u32)PCI_ROM_ADDRESS_MASK;
192 if (res->flags & IORESOURCE_MEM_64) {
195 u64 mask64 = mask | (u64)~0 << 32;
197 pci_read_config_dword(dev, pos + 4, &l);
198 pci_write_config_dword(dev, pos + 4, ~0);
199 pci_read_config_dword(dev, pos + 4, &sz);
200 pci_write_config_dword(dev, pos + 4, l);
202 l64 |= ((u64)l << 32);
203 sz64 |= ((u64)sz << 32);
205 sz64 = pci_size(l64, sz64, mask64);
210 if ((sizeof(resource_size_t) < 8) && (sz64 > 0x100000000ULL)) {
211 dev_err(&dev->dev, "reg %x: can't handle 64-bit BAR\n",
216 if ((sizeof(resource_size_t) < 8) && l) {
217 /* Address above 32-bit boundary; disable the BAR */
218 pci_write_config_dword(dev, pos, 0);
219 pci_write_config_dword(dev, pos + 4, 0);
224 res->end = l64 + sz64;
225 dev_printk(KERN_DEBUG, &dev->dev, "reg %x: %pR\n",
229 sz = pci_size(l, sz, mask);
237 dev_printk(KERN_DEBUG, &dev->dev, "reg %x: %pR\n", pos, res);
241 return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
247 static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
249 unsigned int pos, reg;
251 for (pos = 0; pos < howmany; pos++) {
252 struct resource *res = &dev->resource[pos];
253 reg = PCI_BASE_ADDRESS_0 + (pos << 2);
254 pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
258 struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
259 dev->rom_base_reg = rom;
260 res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
261 IORESOURCE_READONLY | IORESOURCE_CACHEABLE |
262 IORESOURCE_SIZEALIGN;
263 __pci_read_base(dev, pci_bar_mem32, res, rom);
267 static void __devinit pci_read_bridge_io(struct pci_bus *child)
269 struct pci_dev *dev = child->self;
270 u8 io_base_lo, io_limit_lo;
271 unsigned long base, limit;
272 struct resource *res;
274 res = child->resource[0];
275 pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
276 pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
277 base = (io_base_lo & PCI_IO_RANGE_MASK) << 8;
278 limit = (io_limit_lo & PCI_IO_RANGE_MASK) << 8;
280 if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
281 u16 io_base_hi, io_limit_hi;
282 pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
283 pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
284 base |= (io_base_hi << 16);
285 limit |= (io_limit_hi << 16);
288 if (base && base <= limit) {
289 res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
293 res->end = limit + 0xfff;
294 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
298 static void __devinit pci_read_bridge_mmio(struct pci_bus *child)
300 struct pci_dev *dev = child->self;
301 u16 mem_base_lo, mem_limit_lo;
302 unsigned long base, limit;
303 struct resource *res;
305 res = child->resource[1];
306 pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
307 pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
308 base = (mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
309 limit = (mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
310 if (base && base <= limit) {
311 res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
313 res->end = limit + 0xfffff;
314 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
318 static void __devinit pci_read_bridge_mmio_pref(struct pci_bus *child)
320 struct pci_dev *dev = child->self;
321 u16 mem_base_lo, mem_limit_lo;
322 unsigned long base, limit;
323 struct resource *res;
325 res = child->resource[2];
326 pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
327 pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
328 base = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
329 limit = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
331 if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
332 u32 mem_base_hi, mem_limit_hi;
333 pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
334 pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
337 * Some bridges set the base > limit by default, and some
338 * (broken) BIOSes do not initialize them. If we find
339 * this, just assume they are not being used.
341 if (mem_base_hi <= mem_limit_hi) {
342 #if BITS_PER_LONG == 64
343 base |= ((long) mem_base_hi) << 32;
344 limit |= ((long) mem_limit_hi) << 32;
346 if (mem_base_hi || mem_limit_hi) {
347 dev_err(&dev->dev, "can't handle 64-bit "
348 "address space for bridge\n");
354 if (base && base <= limit) {
355 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
356 IORESOURCE_MEM | IORESOURCE_PREFETCH;
357 if (res->flags & PCI_PREF_RANGE_TYPE_64)
358 res->flags |= IORESOURCE_MEM_64;
360 res->end = limit + 0xfffff;
361 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
365 void __devinit pci_read_bridge_bases(struct pci_bus *child)
367 struct pci_dev *dev = child->self;
368 struct resource *res;
371 if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
374 dev_info(&dev->dev, "PCI bridge to [bus %02x-%02x]%s\n",
375 child->secondary, child->subordinate,
376 dev->transparent ? " (subtractive decode)" : "");
378 pci_bus_remove_resources(child);
379 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
380 child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
382 pci_read_bridge_io(child);
383 pci_read_bridge_mmio(child);
384 pci_read_bridge_mmio_pref(child);
386 if (dev->transparent) {
387 pci_bus_for_each_resource(child->parent, res, i) {
389 pci_bus_add_resource(child, res,
390 PCI_SUBTRACTIVE_DECODE);
391 dev_printk(KERN_DEBUG, &dev->dev,
392 " bridge window %pR (subtractive decode)\n",
399 static struct pci_bus * pci_alloc_bus(void)
403 b = kzalloc(sizeof(*b), GFP_KERNEL);
405 INIT_LIST_HEAD(&b->node);
406 INIT_LIST_HEAD(&b->children);
407 INIT_LIST_HEAD(&b->devices);
408 INIT_LIST_HEAD(&b->slots);
409 INIT_LIST_HEAD(&b->resources);
410 b->max_bus_speed = PCI_SPEED_UNKNOWN;
411 b->cur_bus_speed = PCI_SPEED_UNKNOWN;
416 static unsigned char pcix_bus_speed[] = {
417 PCI_SPEED_UNKNOWN, /* 0 */
418 PCI_SPEED_66MHz_PCIX, /* 1 */
419 PCI_SPEED_100MHz_PCIX, /* 2 */
420 PCI_SPEED_133MHz_PCIX, /* 3 */
421 PCI_SPEED_UNKNOWN, /* 4 */
422 PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
423 PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
424 PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
425 PCI_SPEED_UNKNOWN, /* 8 */
426 PCI_SPEED_66MHz_PCIX_266, /* 9 */
427 PCI_SPEED_100MHz_PCIX_266, /* A */
428 PCI_SPEED_133MHz_PCIX_266, /* B */
429 PCI_SPEED_UNKNOWN, /* C */
430 PCI_SPEED_66MHz_PCIX_533, /* D */
431 PCI_SPEED_100MHz_PCIX_533, /* E */
432 PCI_SPEED_133MHz_PCIX_533 /* F */
435 static unsigned char pcie_link_speed[] = {
436 PCI_SPEED_UNKNOWN, /* 0 */
437 PCIE_SPEED_2_5GT, /* 1 */
438 PCIE_SPEED_5_0GT, /* 2 */
439 PCIE_SPEED_8_0GT, /* 3 */
440 PCI_SPEED_UNKNOWN, /* 4 */
441 PCI_SPEED_UNKNOWN, /* 5 */
442 PCI_SPEED_UNKNOWN, /* 6 */
443 PCI_SPEED_UNKNOWN, /* 7 */
444 PCI_SPEED_UNKNOWN, /* 8 */
445 PCI_SPEED_UNKNOWN, /* 9 */
446 PCI_SPEED_UNKNOWN, /* A */
447 PCI_SPEED_UNKNOWN, /* B */
448 PCI_SPEED_UNKNOWN, /* C */
449 PCI_SPEED_UNKNOWN, /* D */
450 PCI_SPEED_UNKNOWN, /* E */
451 PCI_SPEED_UNKNOWN /* F */
454 void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
456 bus->cur_bus_speed = pcie_link_speed[linksta & 0xf];
458 EXPORT_SYMBOL_GPL(pcie_update_link_speed);
460 static unsigned char agp_speeds[] = {
468 static enum pci_bus_speed agp_speed(int agp3, int agpstat)
474 else if (agpstat & 2)
476 else if (agpstat & 1)
488 return agp_speeds[index];
492 static void pci_set_bus_speed(struct pci_bus *bus)
494 struct pci_dev *bridge = bus->self;
497 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
499 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
503 pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
504 bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
506 pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
507 bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
510 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
513 enum pci_bus_speed max;
514 pci_read_config_word(bridge, pos + 2, &status);
516 if (status & 0x8000) {
517 max = PCI_SPEED_133MHz_PCIX_533;
518 } else if (status & 0x4000) {
519 max = PCI_SPEED_133MHz_PCIX_266;
520 } else if (status & 0x0002) {
521 if (((status >> 12) & 0x3) == 2) {
522 max = PCI_SPEED_133MHz_PCIX_ECC;
524 max = PCI_SPEED_133MHz_PCIX;
527 max = PCI_SPEED_66MHz_PCIX;
530 bus->max_bus_speed = max;
531 bus->cur_bus_speed = pcix_bus_speed[(status >> 6) & 0xf];
536 pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
541 pci_read_config_dword(bridge, pos + PCI_EXP_LNKCAP, &linkcap);
542 bus->max_bus_speed = pcie_link_speed[linkcap & 0xf];
544 pci_read_config_word(bridge, pos + PCI_EXP_LNKSTA, &linksta);
545 pcie_update_link_speed(bus, linksta);
550 static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
551 struct pci_dev *bridge, int busnr)
553 struct pci_bus *child;
557 * Allocate a new bus, and inherit stuff from the parent..
559 child = pci_alloc_bus();
563 child->parent = parent;
564 child->ops = parent->ops;
565 child->sysdata = parent->sysdata;
566 child->bus_flags = parent->bus_flags;
568 /* initialize some portions of the bus device, but don't register it
569 * now as the parent is not properly set up yet. This device will get
570 * registered later in pci_bus_add_devices()
572 child->dev.class = &pcibus_class;
573 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
576 * Set up the primary, secondary and subordinate
579 child->number = child->secondary = busnr;
580 child->primary = parent->secondary;
581 child->subordinate = 0xff;
586 child->self = bridge;
587 child->bridge = get_device(&bridge->dev);
588 pci_set_bus_of_node(child);
589 pci_set_bus_speed(child);
591 /* Set up default resource pointers and names.. */
592 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
593 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
594 child->resource[i]->name = child->name;
596 bridge->subordinate = child;
601 struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr)
603 struct pci_bus *child;
605 child = pci_alloc_child_bus(parent, dev, busnr);
607 down_write(&pci_bus_sem);
608 list_add_tail(&child->node, &parent->children);
609 up_write(&pci_bus_sem);
614 static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
616 struct pci_bus *parent = child->parent;
618 /* Attempts to fix that up are really dangerous unless
619 we're going to re-assign all bus numbers. */
620 if (!pcibios_assign_all_busses())
623 while (parent->parent && parent->subordinate < max) {
624 parent->subordinate = max;
625 pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);
626 parent = parent->parent;
631 * If it's a bridge, configure it and scan the bus behind it.
632 * For CardBus bridges, we don't scan behind as the devices will
633 * be handled by the bridge driver itself.
635 * We need to process bridges in two passes -- first we scan those
636 * already configured by the BIOS and after we are done with all of
637 * them, we proceed to assigning numbers to the remaining buses in
638 * order to avoid overlaps between old and new bus numbers.
640 int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
642 struct pci_bus *child;
643 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
646 u8 primary, secondary, subordinate;
649 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
650 primary = buses & 0xFF;
651 secondary = (buses >> 8) & 0xFF;
652 subordinate = (buses >> 16) & 0xFF;
654 dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
655 secondary, subordinate, pass);
657 if (!primary && (primary != bus->number) && secondary && subordinate) {
658 dev_warn(&dev->dev, "Primary bus is hard wired to 0\n");
659 primary = bus->number;
662 /* Check if setup is sensible at all */
664 (primary != bus->number || secondary <= bus->number ||
665 secondary > subordinate)) {
666 dev_info(&dev->dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
667 secondary, subordinate);
671 /* Disable MasterAbortMode during probing to avoid reporting
672 of bus errors (in some architectures) */
673 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
674 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
675 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
677 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
678 !is_cardbus && !broken) {
681 * Bus already configured by firmware, process it in the first
682 * pass and just note the configuration.
688 * If we already got to this bus through a different bridge,
689 * don't re-add it. This can happen with the i450NX chipset.
691 * However, we continue to descend down the hierarchy and
692 * scan remaining child buses.
694 child = pci_find_bus(pci_domain_nr(bus), secondary);
696 child = pci_add_new_bus(bus, dev, secondary);
699 child->primary = primary;
700 child->subordinate = subordinate;
701 child->bridge_ctl = bctl;
704 cmax = pci_scan_child_bus(child);
707 if (child->subordinate > max)
708 max = child->subordinate;
711 * We need to assign a number to this bus which we always
712 * do in the second pass.
715 if (pcibios_assign_all_busses() || broken)
716 /* Temporarily disable forwarding of the
717 configuration cycles on all bridges in
718 this bus segment to avoid possible
719 conflicts in the second pass between two
720 bridges programmed with overlapping
722 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
728 pci_write_config_word(dev, PCI_STATUS, 0xffff);
730 /* Prevent assigning a bus number that already exists.
731 * This can happen when a bridge is hot-plugged, so in
732 * this case we only re-scan this bus. */
733 child = pci_find_bus(pci_domain_nr(bus), max+1);
735 child = pci_add_new_bus(bus, dev, ++max);
739 buses = (buses & 0xff000000)
740 | ((unsigned int)(child->primary) << 0)
741 | ((unsigned int)(child->secondary) << 8)
742 | ((unsigned int)(child->subordinate) << 16);
745 * yenta.c forces a secondary latency timer of 176.
746 * Copy that behaviour here.
749 buses &= ~0xff000000;
750 buses |= CARDBUS_LATENCY_TIMER << 24;
754 * We need to blast all three values with a single write.
756 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
759 child->bridge_ctl = bctl;
761 * Adjust subordinate busnr in parent buses.
762 * We do this before scanning for children because
763 * some devices may not be detected if the bios
766 pci_fixup_parent_subordinate_busnr(child, max);
767 /* Now we can scan all subordinate buses... */
768 max = pci_scan_child_bus(child);
770 * now fix it up again since we have found
771 * the real value of max.
773 pci_fixup_parent_subordinate_busnr(child, max);
776 * For CardBus bridges, we leave 4 bus numbers
777 * as cards with a PCI-to-PCI bridge can be
780 for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
781 struct pci_bus *parent = bus;
782 if (pci_find_bus(pci_domain_nr(bus),
785 while (parent->parent) {
786 if ((!pcibios_assign_all_busses()) &&
787 (parent->subordinate > max) &&
788 (parent->subordinate <= max+i)) {
791 parent = parent->parent;
795 * Often, there are two cardbus bridges
796 * -- try to leave one valid bus number
804 pci_fixup_parent_subordinate_busnr(child, max);
807 * Set the subordinate bus number to its real value.
809 child->subordinate = max;
810 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
814 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
815 pci_domain_nr(bus), child->number);
817 /* Has only triggered on CardBus, fixup is in yenta_socket */
818 while (bus->parent) {
819 if ((child->subordinate > bus->subordinate) ||
820 (child->number > bus->subordinate) ||
821 (child->number < bus->number) ||
822 (child->subordinate < bus->number)) {
823 dev_info(&child->dev, "[bus %02x-%02x] %s "
824 "hidden behind%s bridge %s [bus %02x-%02x]\n",
825 child->number, child->subordinate,
826 (bus->number > child->subordinate &&
827 bus->subordinate < child->number) ?
828 "wholly" : "partially",
829 bus->self->transparent ? " transparent" : "",
831 bus->number, bus->subordinate);
837 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
843 * Read interrupt line and base address registers.
844 * The architecture-dependent code can tweak these, of course.
846 static void pci_read_irq(struct pci_dev *dev)
850 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
853 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
857 void set_pcie_port_type(struct pci_dev *pdev)
862 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
866 pdev->pcie_cap = pos;
867 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
868 pdev->pcie_type = (reg16 & PCI_EXP_FLAGS_TYPE) >> 4;
869 pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16);
870 pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
873 void set_pcie_hotplug_bridge(struct pci_dev *pdev)
879 pos = pci_pcie_cap(pdev);
882 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
883 if (!(reg16 & PCI_EXP_FLAGS_SLOT))
885 pci_read_config_dword(pdev, pos + PCI_EXP_SLTCAP, ®32);
886 if (reg32 & PCI_EXP_SLTCAP_HPC)
887 pdev->is_hotplug_bridge = 1;
890 #define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
893 * pci_setup_device - fill in class and map information of a device
894 * @dev: the device structure to fill
896 * Initialize the device structure with information about the device's
897 * vendor,class,memory and IO-space addresses,IRQ lines etc.
898 * Called at initialisation of the PCI subsystem and by CardBus services.
899 * Returns 0 on success and negative if unknown type of device (not normal,
900 * bridge or CardBus).
902 int pci_setup_device(struct pci_dev *dev)
906 struct pci_slot *slot;
909 if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
912 dev->sysdata = dev->bus->sysdata;
913 dev->dev.parent = dev->bus->bridge;
914 dev->dev.bus = &pci_bus_type;
915 dev->hdr_type = hdr_type & 0x7f;
916 dev->multifunction = !!(hdr_type & 0x80);
917 dev->error_state = pci_channel_io_normal;
918 set_pcie_port_type(dev);
920 list_for_each_entry(slot, &dev->bus->slots, list)
921 if (PCI_SLOT(dev->devfn) == slot->number)
924 /* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
925 set this higher, assuming the system even supports it. */
926 dev->dma_mask = 0xffffffff;
928 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
929 dev->bus->number, PCI_SLOT(dev->devfn),
930 PCI_FUNC(dev->devfn));
932 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
933 dev->revision = class & 0xff;
934 class >>= 8; /* upper 3 bytes */
938 dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %d class %#08x\n",
939 dev->vendor, dev->device, dev->hdr_type, class);
941 /* need to have dev->class ready */
942 dev->cfg_size = pci_cfg_space_size(dev);
944 /* "Unknown power state" */
945 dev->current_state = PCI_UNKNOWN;
947 /* Early fixups, before probing the BARs */
948 pci_fixup_device(pci_fixup_early, dev);
949 /* device class may be changed after fixup */
950 class = dev->class >> 8;
952 switch (dev->hdr_type) { /* header type */
953 case PCI_HEADER_TYPE_NORMAL: /* standard header */
954 if (class == PCI_CLASS_BRIDGE_PCI)
957 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
958 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
959 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
962 * Do the ugly legacy mode stuff here rather than broken chip
963 * quirk code. Legacy mode ATA controllers have fixed
964 * addresses. These are not always echoed in BAR0-3, and
965 * BAR0-3 in a few cases contain junk!
967 if (class == PCI_CLASS_STORAGE_IDE) {
969 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
970 if ((progif & 1) == 0) {
971 dev->resource[0].start = 0x1F0;
972 dev->resource[0].end = 0x1F7;
973 dev->resource[0].flags = LEGACY_IO_RESOURCE;
974 dev->resource[1].start = 0x3F6;
975 dev->resource[1].end = 0x3F6;
976 dev->resource[1].flags = LEGACY_IO_RESOURCE;
978 if ((progif & 4) == 0) {
979 dev->resource[2].start = 0x170;
980 dev->resource[2].end = 0x177;
981 dev->resource[2].flags = LEGACY_IO_RESOURCE;
982 dev->resource[3].start = 0x376;
983 dev->resource[3].end = 0x376;
984 dev->resource[3].flags = LEGACY_IO_RESOURCE;
989 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
990 if (class != PCI_CLASS_BRIDGE_PCI)
992 /* The PCI-to-PCI bridge spec requires that subtractive
993 decoding (i.e. transparent) bridge must have programming
994 interface code of 0x01. */
996 dev->transparent = ((dev->class & 0xff) == 1);
997 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
998 set_pcie_hotplug_bridge(dev);
999 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1001 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1002 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1006 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1007 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1010 pci_read_bases(dev, 1, 0);
1011 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1012 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1015 default: /* unknown header */
1016 dev_err(&dev->dev, "unknown header type %02x, "
1017 "ignoring device\n", dev->hdr_type);
1021 dev_err(&dev->dev, "ignoring class %02x (doesn't match header "
1022 "type %02x)\n", class, dev->hdr_type);
1023 dev->class = PCI_CLASS_NOT_DEFINED;
1026 /* We found a fine healthy device, go go go... */
1030 static void pci_release_capabilities(struct pci_dev *dev)
1032 pci_vpd_release(dev);
1033 pci_iov_release(dev);
1037 * pci_release_dev - free a pci device structure when all users of it are finished.
1038 * @dev: device that's been disconnected
1040 * Will be called only by the device core when all users of this pci device are
1043 static void pci_release_dev(struct device *dev)
1045 struct pci_dev *pci_dev;
1047 pci_dev = to_pci_dev(dev);
1048 pci_release_capabilities(pci_dev);
1049 pci_release_of_node(pci_dev);
1054 * pci_cfg_space_size - get the configuration space size of the PCI device.
1057 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1058 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1059 * access it. Maybe we don't have a way to generate extended config space
1060 * accesses, or the device is behind a reverse Express bridge. So we try
1061 * reading the dword at 0x100 which must either be 0 or a valid extended
1062 * capability header.
1064 int pci_cfg_space_size_ext(struct pci_dev *dev)
1067 int pos = PCI_CFG_SPACE_SIZE;
1069 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1071 if (status == 0xffffffff)
1074 return PCI_CFG_SPACE_EXP_SIZE;
1077 return PCI_CFG_SPACE_SIZE;
1080 int pci_cfg_space_size(struct pci_dev *dev)
1086 class = dev->class >> 8;
1087 if (class == PCI_CLASS_BRIDGE_HOST)
1088 return pci_cfg_space_size_ext(dev);
1090 pos = pci_pcie_cap(dev);
1092 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1096 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1097 if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
1101 return pci_cfg_space_size_ext(dev);
1104 return PCI_CFG_SPACE_SIZE;
1107 static void pci_release_bus_bridge_dev(struct device *dev)
1112 struct pci_dev *alloc_pci_dev(void)
1114 struct pci_dev *dev;
1116 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
1120 INIT_LIST_HEAD(&dev->bus_list);
1124 EXPORT_SYMBOL(alloc_pci_dev);
1127 * Read the config data for a PCI device, sanity-check it
1128 * and fill in the dev structure...
1130 static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
1132 struct pci_dev *dev;
1136 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, &l))
1139 /* some broken boards return 0 or ~0 if a slot is empty: */
1140 if (l == 0xffffffff || l == 0x00000000 ||
1141 l == 0x0000ffff || l == 0xffff0000)
1144 /* Configuration request Retry Status */
1145 while (l == 0xffff0001) {
1148 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, &l))
1150 /* Card hasn't responded in 60 seconds? Must be stuck. */
1151 if (delay > 60 * 1000) {
1152 printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not "
1153 "responding\n", pci_domain_nr(bus),
1154 bus->number, PCI_SLOT(devfn),
1160 dev = alloc_pci_dev();
1166 dev->vendor = l & 0xffff;
1167 dev->device = (l >> 16) & 0xffff;
1169 pci_set_of_node(dev);
1171 if (pci_setup_device(dev)) {
1179 static void pci_init_capabilities(struct pci_dev *dev)
1181 /* MSI/MSI-X list */
1182 pci_msi_init_pci_dev(dev);
1184 /* Buffers for saving PCIe and PCI-X capabilities */
1185 pci_allocate_cap_save_buffers(dev);
1187 /* Power Management */
1189 platform_pci_wakeup_init(dev);
1191 /* Vital Product Data */
1192 pci_vpd_pci22_init(dev);
1194 /* Alternative Routing-ID Forwarding */
1195 pci_enable_ari(dev);
1197 /* Single Root I/O Virtualization */
1200 /* Enable ACS P2P upstream forwarding */
1201 pci_enable_acs(dev);
1204 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
1206 device_initialize(&dev->dev);
1207 dev->dev.release = pci_release_dev;
1210 dev->dev.dma_mask = &dev->dma_mask;
1211 dev->dev.dma_parms = &dev->dma_parms;
1212 dev->dev.coherent_dma_mask = 0xffffffffull;
1214 pci_set_dma_max_seg_size(dev, 65536);
1215 pci_set_dma_seg_boundary(dev, 0xffffffff);
1217 /* Fix up broken headers */
1218 pci_fixup_device(pci_fixup_header, dev);
1220 /* Clear the state_saved flag. */
1221 dev->state_saved = false;
1223 /* Initialize various capabilities */
1224 pci_init_capabilities(dev);
1227 * Add the device to our list of discovered devices
1228 * and the bus list for fixup functions, etc.
1230 down_write(&pci_bus_sem);
1231 list_add_tail(&dev->bus_list, &bus->devices);
1232 up_write(&pci_bus_sem);
1235 struct pci_dev *__ref pci_scan_single_device(struct pci_bus *bus, int devfn)
1237 struct pci_dev *dev;
1239 dev = pci_get_slot(bus, devfn);
1245 dev = pci_scan_device(bus, devfn);
1249 pci_device_add(dev, bus);
1253 EXPORT_SYMBOL(pci_scan_single_device);
1255 static unsigned next_ari_fn(struct pci_dev *dev, unsigned fn)
1258 unsigned pos, next_fn;
1263 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1266 pci_read_config_word(dev, pos + 4, &cap);
1273 static unsigned next_trad_fn(struct pci_dev *dev, unsigned fn)
1275 return (fn + 1) % 8;
1278 static unsigned no_next_fn(struct pci_dev *dev, unsigned fn)
1283 static int only_one_child(struct pci_bus *bus)
1285 struct pci_dev *parent = bus->self;
1286 if (!parent || !pci_is_pcie(parent))
1288 if (parent->pcie_type == PCI_EXP_TYPE_ROOT_PORT ||
1289 parent->pcie_type == PCI_EXP_TYPE_DOWNSTREAM)
1295 * pci_scan_slot - scan a PCI slot on a bus for devices.
1296 * @bus: PCI bus to scan
1297 * @devfn: slot number to scan (must have zero function.)
1299 * Scan a PCI slot on the specified PCI bus for devices, adding
1300 * discovered devices to the @bus->devices list. New devices
1301 * will not have is_added set.
1303 * Returns the number of new devices found.
1305 int pci_scan_slot(struct pci_bus *bus, int devfn)
1307 unsigned fn, nr = 0;
1308 struct pci_dev *dev;
1309 unsigned (*next_fn)(struct pci_dev *, unsigned) = no_next_fn;
1311 if (only_one_child(bus) && (devfn > 0))
1312 return 0; /* Already scanned the entire slot */
1314 dev = pci_scan_single_device(bus, devfn);
1320 if (pci_ari_enabled(bus))
1321 next_fn = next_ari_fn;
1322 else if (dev->multifunction)
1323 next_fn = next_trad_fn;
1325 for (fn = next_fn(dev, 0); fn > 0; fn = next_fn(dev, fn)) {
1326 dev = pci_scan_single_device(bus, devfn + fn);
1330 dev->multifunction = 1;
1334 /* only one slot has pcie device */
1335 if (bus->self && nr)
1336 pcie_aspm_init_link_state(bus->self);
1341 static int pcie_find_smpss(struct pci_dev *dev, void *data)
1345 if (!pci_is_pcie(dev))
1348 /* For PCIE hotplug enabled slots not connected directly to a
1349 * PCI-E root port, there can be problems when hotplugging
1350 * devices. This is due to the possibility of hotplugging a
1351 * device into the fabric with a smaller MPS that the devices
1352 * currently running have configured. Modifying the MPS on the
1353 * running devices could cause a fatal bus error due to an
1354 * incoming frame being larger than the newly configured MPS.
1355 * To work around this, the MPS for the entire fabric must be
1356 * set to the minimum size. Any devices hotplugged into this
1357 * fabric will have the minimum MPS set. If the PCI hotplug
1358 * slot is directly connected to the root port and there are not
1359 * other devices on the fabric (which seems to be the most
1360 * common case), then this is not an issue and MPS discovery
1361 * will occur as normal.
1363 if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) ||
1365 dev->bus->self->pcie_type != PCI_EXP_TYPE_ROOT_PORT)))
1368 if (*smpss > dev->pcie_mpss)
1369 *smpss = dev->pcie_mpss;
1374 static void pcie_write_mps(struct pci_dev *dev, int mps)
1378 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
1379 mps = 128 << dev->pcie_mpss;
1381 if (dev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && dev->bus->self)
1382 /* For "Performance", the assumption is made that
1383 * downstream communication will never be larger than
1384 * the MRRS. So, the MPS only needs to be configured
1385 * for the upstream communication. This being the case,
1386 * walk from the top down and set the MPS of the child
1387 * to that of the parent bus.
1389 * Configure the device MPS with the smaller of the
1390 * device MPSS or the bridge MPS (which is assumed to be
1391 * properly configured at this point to the largest
1392 * allowable MPS based on its parent bus).
1394 mps = min(mps, pcie_get_mps(dev->bus->self));
1397 rc = pcie_set_mps(dev, mps);
1399 dev_err(&dev->dev, "Failed attempting to set the MPS\n");
1402 static void pcie_write_mrrs(struct pci_dev *dev)
1406 /* In the "safe" case, do not configure the MRRS. There appear to be
1407 * issues with setting MRRS to 0 on a number of devices.
1409 if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
1412 /* For Max performance, the MRRS must be set to the largest supported
1413 * value. However, it cannot be configured larger than the MPS the
1414 * device or the bus can support. This should already be properly
1415 * configured by a prior call to pcie_write_mps.
1417 mrrs = pcie_get_mps(dev);
1419 /* MRRS is a R/W register. Invalid values can be written, but a
1420 * subsequent read will verify if the value is acceptable or not.
1421 * If the MRRS value provided is not acceptable (e.g., too large),
1422 * shrink the value until it is acceptable to the HW.
1424 while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
1425 rc = pcie_set_readrq(dev, mrrs);
1429 dev_warn(&dev->dev, "Failed attempting to set the MRRS\n");
1434 dev_err(&dev->dev, "MRRS was unable to be configured with a "
1435 "safe value. If problems are experienced, try running "
1436 "with pci=pcie_bus_safe.\n");
1439 static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
1443 if (!pci_is_pcie(dev))
1446 mps = 128 << *(u8 *)data;
1447 orig_mps = pcie_get_mps(dev);
1449 pcie_write_mps(dev, mps);
1450 pcie_write_mrrs(dev);
1452 dev_info(&dev->dev, "PCI-E Max Payload Size set to %4d/%4d (was %4d), "
1453 "Max Read Rq %4d\n", pcie_get_mps(dev), 128 << dev->pcie_mpss,
1454 orig_mps, pcie_get_readrq(dev));
1459 /* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down,
1460 * parents then children fashion. If this changes, then this code will not
1463 void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss)
1467 if (!pci_is_pcie(bus->self))
1470 if (pcie_bus_config == PCIE_BUS_TUNE_OFF)
1473 /* FIXME - Peer to peer DMA is possible, though the endpoint would need
1474 * to be aware to the MPS of the destination. To work around this,
1475 * simply force the MPS of the entire system to the smallest possible.
1477 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
1480 if (pcie_bus_config == PCIE_BUS_SAFE) {
1483 pcie_find_smpss(bus->self, &smpss);
1484 pci_walk_bus(bus, pcie_find_smpss, &smpss);
1487 pcie_bus_configure_set(bus->self, &smpss);
1488 pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
1490 EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
1492 unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
1494 unsigned int devfn, pass, max = bus->secondary;
1495 struct pci_dev *dev;
1497 dev_dbg(&bus->dev, "scanning bus\n");
1499 /* Go find them, Rover! */
1500 for (devfn = 0; devfn < 0x100; devfn += 8)
1501 pci_scan_slot(bus, devfn);
1503 /* Reserve buses for SR-IOV capability. */
1504 max += pci_iov_bus_range(bus);
1507 * After performing arch-dependent fixup of the bus, look behind
1508 * all PCI-to-PCI bridges on this bus.
1510 if (!bus->is_added) {
1511 dev_dbg(&bus->dev, "fixups for bus\n");
1512 pcibios_fixup_bus(bus);
1513 if (pci_is_root_bus(bus))
1517 for (pass=0; pass < 2; pass++)
1518 list_for_each_entry(dev, &bus->devices, bus_list) {
1519 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
1520 dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
1521 max = pci_scan_bridge(bus, dev, max, pass);
1525 * We've scanned the bus and so we know all about what's on
1526 * the other side of any bridges that may be on this bus plus
1529 * Return how far we've got finding sub-buses.
1531 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
1535 struct pci_bus * pci_create_bus(struct device *parent,
1536 int bus, struct pci_ops *ops, void *sysdata)
1539 struct pci_bus *b, *b2;
1542 b = pci_alloc_bus();
1546 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1552 b->sysdata = sysdata;
1555 b2 = pci_find_bus(pci_domain_nr(b), bus);
1557 /* If we already got to this bus through a different bridge, ignore it */
1558 dev_dbg(&b2->dev, "bus already known\n");
1562 down_write(&pci_bus_sem);
1563 list_add_tail(&b->node, &pci_root_buses);
1564 up_write(&pci_bus_sem);
1566 dev->parent = parent;
1567 dev->release = pci_release_bus_bridge_dev;
1568 dev_set_name(dev, "pci%04x:%02x", pci_domain_nr(b), bus);
1569 error = device_register(dev);
1572 b->bridge = get_device(dev);
1573 device_enable_async_suspend(b->bridge);
1574 pci_set_bus_of_node(b);
1577 set_dev_node(b->bridge, pcibus_to_node(b));
1579 b->dev.class = &pcibus_class;
1580 b->dev.parent = b->bridge;
1581 dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
1582 error = device_register(&b->dev);
1584 goto class_dev_reg_err;
1586 /* Create legacy_io and legacy_mem files for this bus */
1587 pci_create_legacy_files(b);
1589 b->number = b->secondary = bus;
1590 b->resource[0] = &ioport_resource;
1591 b->resource[1] = &iomem_resource;
1596 device_unregister(dev);
1598 down_write(&pci_bus_sem);
1600 up_write(&pci_bus_sem);
1607 struct pci_bus * __devinit pci_scan_bus_parented(struct device *parent,
1608 int bus, struct pci_ops *ops, void *sysdata)
1612 b = pci_create_bus(parent, bus, ops, sysdata);
1614 b->subordinate = pci_scan_child_bus(b);
1617 EXPORT_SYMBOL(pci_scan_bus_parented);
1619 #ifdef CONFIG_HOTPLUG
1621 * pci_rescan_bus - scan a PCI bus for devices.
1622 * @bus: PCI bus to scan
1624 * Scan a PCI bus and child buses for new devices, adds them,
1627 * Returns the max number of subordinate bus discovered.
1629 unsigned int __ref pci_rescan_bus(struct pci_bus *bus)
1632 struct pci_dev *dev;
1634 max = pci_scan_child_bus(bus);
1636 down_read(&pci_bus_sem);
1637 list_for_each_entry(dev, &bus->devices, bus_list)
1638 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
1639 dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
1640 if (dev->subordinate)
1641 pci_bus_size_bridges(dev->subordinate);
1642 up_read(&pci_bus_sem);
1644 pci_bus_assign_resources(bus);
1645 pci_enable_bridges(bus);
1646 pci_bus_add_devices(bus);
1650 EXPORT_SYMBOL_GPL(pci_rescan_bus);
1652 EXPORT_SYMBOL(pci_add_new_bus);
1653 EXPORT_SYMBOL(pci_scan_slot);
1654 EXPORT_SYMBOL(pci_scan_bridge);
1655 EXPORT_SYMBOL_GPL(pci_scan_child_bus);
1658 static int __init pci_sort_bf_cmp(const struct device *d_a, const struct device *d_b)
1660 const struct pci_dev *a = to_pci_dev(d_a);
1661 const struct pci_dev *b = to_pci_dev(d_b);
1663 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
1664 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
1666 if (a->bus->number < b->bus->number) return -1;
1667 else if (a->bus->number > b->bus->number) return 1;
1669 if (a->devfn < b->devfn) return -1;
1670 else if (a->devfn > b->devfn) return 1;
1675 void __init pci_sort_breadthfirst(void)
1677 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);