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>
13 #include <asm-generic/pci-bridge.h>
16 #define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
17 #define CARDBUS_RESERVE_BUSNR 3
19 struct resource busn_resource = {
23 .flags = IORESOURCE_BUS,
26 /* Ugh. Need to stop exporting this to modules. */
27 LIST_HEAD(pci_root_buses);
28 EXPORT_SYMBOL(pci_root_buses);
30 static LIST_HEAD(pci_domain_busn_res_list);
32 struct pci_domain_busn_res {
33 struct list_head list;
38 static struct resource *get_pci_domain_busn_res(int domain_nr)
40 struct pci_domain_busn_res *r;
42 list_for_each_entry(r, &pci_domain_busn_res_list, list)
43 if (r->domain_nr == domain_nr)
46 r = kzalloc(sizeof(*r), GFP_KERNEL);
50 r->domain_nr = domain_nr;
53 r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
55 list_add_tail(&r->list, &pci_domain_busn_res_list);
60 static int find_anything(struct device *dev, void *data)
66 * Some device drivers need know if pci is initiated.
67 * Basically, we think pci is not initiated when there
68 * is no device to be found on the pci_bus_type.
70 int no_pci_devices(void)
75 dev = bus_find_device(&pci_bus_type, NULL, NULL, find_anything);
76 no_devices = (dev == NULL);
80 EXPORT_SYMBOL(no_pci_devices);
85 static void release_pcibus_dev(struct device *dev)
87 struct pci_bus *pci_bus = to_pci_bus(dev);
90 put_device(pci_bus->bridge);
91 pci_bus_remove_resources(pci_bus);
92 pci_release_bus_of_node(pci_bus);
96 static struct class pcibus_class = {
98 .dev_release = &release_pcibus_dev,
99 .dev_attrs = pcibus_dev_attrs,
102 static int __init pcibus_class_init(void)
104 return class_register(&pcibus_class);
106 postcore_initcall(pcibus_class_init);
108 static u64 pci_size(u64 base, u64 maxbase, u64 mask)
110 u64 size = mask & maxbase; /* Find the significant bits */
114 /* Get the lowest of them to find the decode size, and
115 from that the extent. */
116 size = (size & ~(size-1)) - 1;
118 /* base == maxbase can be valid only if the BAR has
119 already been programmed with all 1s. */
120 if (base == maxbase && ((base | size) & mask) != mask)
126 static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
131 if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
132 flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
133 flags |= IORESOURCE_IO;
137 flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
138 flags |= IORESOURCE_MEM;
139 if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
140 flags |= IORESOURCE_PREFETCH;
142 mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
144 case PCI_BASE_ADDRESS_MEM_TYPE_32:
146 case PCI_BASE_ADDRESS_MEM_TYPE_1M:
147 /* 1M mem BAR treated as 32-bit BAR */
149 case PCI_BASE_ADDRESS_MEM_TYPE_64:
150 flags |= IORESOURCE_MEM_64;
153 /* mem unknown type treated as 32-bit BAR */
160 * pci_read_base - read a PCI BAR
161 * @dev: the PCI device
162 * @type: type of the BAR
163 * @res: resource buffer to be filled in
164 * @pos: BAR position in the config space
166 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
168 int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
169 struct resource *res, unsigned int pos)
173 struct pci_bus_region region;
174 bool bar_too_big = false, bar_disabled = false;
176 mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
178 /* No printks while decoding is disabled! */
179 if (!dev->mmio_always_on) {
180 pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
181 pci_write_config_word(dev, PCI_COMMAND,
182 orig_cmd & ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO));
185 res->name = pci_name(dev);
187 pci_read_config_dword(dev, pos, &l);
188 pci_write_config_dword(dev, pos, l | mask);
189 pci_read_config_dword(dev, pos, &sz);
190 pci_write_config_dword(dev, pos, l);
193 * All bits set in sz means the device isn't working properly.
194 * If the BAR isn't implemented, all bits must be 0. If it's a
195 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
198 if (!sz || sz == 0xffffffff)
202 * I don't know how l can have all bits set. Copied from old code.
203 * Maybe it fixes a bug on some ancient platform.
208 if (type == pci_bar_unknown) {
209 res->flags = decode_bar(dev, l);
210 res->flags |= IORESOURCE_SIZEALIGN;
211 if (res->flags & IORESOURCE_IO) {
212 l &= PCI_BASE_ADDRESS_IO_MASK;
213 mask = PCI_BASE_ADDRESS_IO_MASK & (u32) IO_SPACE_LIMIT;
215 l &= PCI_BASE_ADDRESS_MEM_MASK;
216 mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
219 res->flags |= (l & IORESOURCE_ROM_ENABLE);
220 l &= PCI_ROM_ADDRESS_MASK;
221 mask = (u32)PCI_ROM_ADDRESS_MASK;
224 if (res->flags & IORESOURCE_MEM_64) {
227 u64 mask64 = mask | (u64)~0 << 32;
229 pci_read_config_dword(dev, pos + 4, &l);
230 pci_write_config_dword(dev, pos + 4, ~0);
231 pci_read_config_dword(dev, pos + 4, &sz);
232 pci_write_config_dword(dev, pos + 4, l);
234 l64 |= ((u64)l << 32);
235 sz64 |= ((u64)sz << 32);
237 sz64 = pci_size(l64, sz64, mask64);
242 if ((sizeof(resource_size_t) < 8) && (sz64 > 0x100000000ULL)) {
247 if ((sizeof(resource_size_t) < 8) && l) {
248 /* Address above 32-bit boundary; disable the BAR */
249 pci_write_config_dword(dev, pos, 0);
250 pci_write_config_dword(dev, pos + 4, 0);
253 pcibios_bus_to_resource(dev, res, ®ion);
257 region.end = l64 + sz64;
258 pcibios_bus_to_resource(dev, res, ®ion);
261 sz = pci_size(l, sz, mask);
268 pcibios_bus_to_resource(dev, res, ®ion);
277 if (!dev->mmio_always_on)
278 pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
281 dev_err(&dev->dev, "reg %x: can't handle 64-bit BAR\n", pos);
282 if (res->flags && !bar_disabled)
283 dev_printk(KERN_DEBUG, &dev->dev, "reg %x: %pR\n", pos, res);
285 return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
288 static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
290 unsigned int pos, reg;
292 for (pos = 0; pos < howmany; pos++) {
293 struct resource *res = &dev->resource[pos];
294 reg = PCI_BASE_ADDRESS_0 + (pos << 2);
295 pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
299 struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
300 dev->rom_base_reg = rom;
301 res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
302 IORESOURCE_READONLY | IORESOURCE_CACHEABLE |
303 IORESOURCE_SIZEALIGN;
304 __pci_read_base(dev, pci_bar_mem32, res, rom);
308 static void __devinit pci_read_bridge_io(struct pci_bus *child)
310 struct pci_dev *dev = child->self;
311 u8 io_base_lo, io_limit_lo;
312 unsigned long io_mask, io_granularity, base, limit;
313 struct pci_bus_region region;
314 struct resource *res;
316 io_mask = PCI_IO_RANGE_MASK;
317 io_granularity = 0x1000;
318 if (dev->io_window_1k) {
319 /* Support 1K I/O space granularity */
320 io_mask = PCI_IO_1K_RANGE_MASK;
321 io_granularity = 0x400;
324 res = child->resource[0];
325 pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
326 pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
327 base = (io_base_lo & io_mask) << 8;
328 limit = (io_limit_lo & io_mask) << 8;
330 if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
331 u16 io_base_hi, io_limit_hi;
333 pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
334 pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
335 base |= ((unsigned long) io_base_hi << 16);
336 limit |= ((unsigned long) io_limit_hi << 16);
340 res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
342 region.end = limit + io_granularity - 1;
343 pcibios_bus_to_resource(dev, res, ®ion);
344 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
348 static void __devinit pci_read_bridge_mmio(struct pci_bus *child)
350 struct pci_dev *dev = child->self;
351 u16 mem_base_lo, mem_limit_lo;
352 unsigned long base, limit;
353 struct pci_bus_region region;
354 struct resource *res;
356 res = child->resource[1];
357 pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
358 pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
359 base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
360 limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
362 res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
364 region.end = limit + 0xfffff;
365 pcibios_bus_to_resource(dev, res, ®ion);
366 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
370 static void __devinit pci_read_bridge_mmio_pref(struct pci_bus *child)
372 struct pci_dev *dev = child->self;
373 u16 mem_base_lo, mem_limit_lo;
374 unsigned long base, limit;
375 struct pci_bus_region region;
376 struct resource *res;
378 res = child->resource[2];
379 pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
380 pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
381 base = ((unsigned long) mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
382 limit = ((unsigned long) mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
384 if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
385 u32 mem_base_hi, mem_limit_hi;
387 pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
388 pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
391 * Some bridges set the base > limit by default, and some
392 * (broken) BIOSes do not initialize them. If we find
393 * this, just assume they are not being used.
395 if (mem_base_hi <= mem_limit_hi) {
396 #if BITS_PER_LONG == 64
397 base |= ((unsigned long) mem_base_hi) << 32;
398 limit |= ((unsigned long) mem_limit_hi) << 32;
400 if (mem_base_hi || mem_limit_hi) {
401 dev_err(&dev->dev, "can't handle 64-bit "
402 "address space for bridge\n");
409 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
410 IORESOURCE_MEM | IORESOURCE_PREFETCH;
411 if (res->flags & PCI_PREF_RANGE_TYPE_64)
412 res->flags |= IORESOURCE_MEM_64;
414 region.end = limit + 0xfffff;
415 pcibios_bus_to_resource(dev, res, ®ion);
416 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
420 void __devinit pci_read_bridge_bases(struct pci_bus *child)
422 struct pci_dev *dev = child->self;
423 struct resource *res;
426 if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
429 dev_info(&dev->dev, "PCI bridge to %pR%s\n",
431 dev->transparent ? " (subtractive decode)" : "");
433 pci_bus_remove_resources(child);
434 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
435 child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
437 pci_read_bridge_io(child);
438 pci_read_bridge_mmio(child);
439 pci_read_bridge_mmio_pref(child);
441 if (dev->transparent) {
442 pci_bus_for_each_resource(child->parent, res, i) {
444 pci_bus_add_resource(child, res,
445 PCI_SUBTRACTIVE_DECODE);
446 dev_printk(KERN_DEBUG, &dev->dev,
447 " bridge window %pR (subtractive decode)\n",
454 static struct pci_bus * pci_alloc_bus(void)
458 b = kzalloc(sizeof(*b), GFP_KERNEL);
460 INIT_LIST_HEAD(&b->node);
461 INIT_LIST_HEAD(&b->children);
462 INIT_LIST_HEAD(&b->devices);
463 INIT_LIST_HEAD(&b->slots);
464 INIT_LIST_HEAD(&b->resources);
465 b->max_bus_speed = PCI_SPEED_UNKNOWN;
466 b->cur_bus_speed = PCI_SPEED_UNKNOWN;
471 static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b)
473 struct pci_host_bridge *bridge;
475 bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
477 INIT_LIST_HEAD(&bridge->windows);
484 static unsigned char pcix_bus_speed[] = {
485 PCI_SPEED_UNKNOWN, /* 0 */
486 PCI_SPEED_66MHz_PCIX, /* 1 */
487 PCI_SPEED_100MHz_PCIX, /* 2 */
488 PCI_SPEED_133MHz_PCIX, /* 3 */
489 PCI_SPEED_UNKNOWN, /* 4 */
490 PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
491 PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
492 PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
493 PCI_SPEED_UNKNOWN, /* 8 */
494 PCI_SPEED_66MHz_PCIX_266, /* 9 */
495 PCI_SPEED_100MHz_PCIX_266, /* A */
496 PCI_SPEED_133MHz_PCIX_266, /* B */
497 PCI_SPEED_UNKNOWN, /* C */
498 PCI_SPEED_66MHz_PCIX_533, /* D */
499 PCI_SPEED_100MHz_PCIX_533, /* E */
500 PCI_SPEED_133MHz_PCIX_533 /* F */
503 static unsigned char pcie_link_speed[] = {
504 PCI_SPEED_UNKNOWN, /* 0 */
505 PCIE_SPEED_2_5GT, /* 1 */
506 PCIE_SPEED_5_0GT, /* 2 */
507 PCIE_SPEED_8_0GT, /* 3 */
508 PCI_SPEED_UNKNOWN, /* 4 */
509 PCI_SPEED_UNKNOWN, /* 5 */
510 PCI_SPEED_UNKNOWN, /* 6 */
511 PCI_SPEED_UNKNOWN, /* 7 */
512 PCI_SPEED_UNKNOWN, /* 8 */
513 PCI_SPEED_UNKNOWN, /* 9 */
514 PCI_SPEED_UNKNOWN, /* A */
515 PCI_SPEED_UNKNOWN, /* B */
516 PCI_SPEED_UNKNOWN, /* C */
517 PCI_SPEED_UNKNOWN, /* D */
518 PCI_SPEED_UNKNOWN, /* E */
519 PCI_SPEED_UNKNOWN /* F */
522 void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
524 bus->cur_bus_speed = pcie_link_speed[linksta & 0xf];
526 EXPORT_SYMBOL_GPL(pcie_update_link_speed);
528 static unsigned char agp_speeds[] = {
536 static enum pci_bus_speed agp_speed(int agp3, int agpstat)
542 else if (agpstat & 2)
544 else if (agpstat & 1)
556 return agp_speeds[index];
560 static void pci_set_bus_speed(struct pci_bus *bus)
562 struct pci_dev *bridge = bus->self;
565 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
567 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
571 pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
572 bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
574 pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
575 bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
578 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
581 enum pci_bus_speed max;
582 pci_read_config_word(bridge, pos + 2, &status);
584 if (status & 0x8000) {
585 max = PCI_SPEED_133MHz_PCIX_533;
586 } else if (status & 0x4000) {
587 max = PCI_SPEED_133MHz_PCIX_266;
588 } else if (status & 0x0002) {
589 if (((status >> 12) & 0x3) == 2) {
590 max = PCI_SPEED_133MHz_PCIX_ECC;
592 max = PCI_SPEED_133MHz_PCIX;
595 max = PCI_SPEED_66MHz_PCIX;
598 bus->max_bus_speed = max;
599 bus->cur_bus_speed = pcix_bus_speed[(status >> 6) & 0xf];
604 pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
609 pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
610 bus->max_bus_speed = pcie_link_speed[linkcap & 0xf];
612 pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
613 pcie_update_link_speed(bus, linksta);
618 static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
619 struct pci_dev *bridge, int busnr)
621 struct pci_bus *child;
625 * Allocate a new bus, and inherit stuff from the parent..
627 child = pci_alloc_bus();
631 child->parent = parent;
632 child->ops = parent->ops;
633 child->sysdata = parent->sysdata;
634 child->bus_flags = parent->bus_flags;
636 /* initialize some portions of the bus device, but don't register it
637 * now as the parent is not properly set up yet. This device will get
638 * registered later in pci_bus_add_devices()
640 child->dev.class = &pcibus_class;
641 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
644 * Set up the primary, secondary and subordinate
647 child->number = child->busn_res.start = busnr;
648 child->primary = parent->busn_res.start;
649 child->busn_res.end = 0xff;
654 child->self = bridge;
655 child->bridge = get_device(&bridge->dev);
656 pci_set_bus_of_node(child);
657 pci_set_bus_speed(child);
659 /* Set up default resource pointers and names.. */
660 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
661 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
662 child->resource[i]->name = child->name;
664 bridge->subordinate = child;
669 struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr)
671 struct pci_bus *child;
673 child = pci_alloc_child_bus(parent, dev, busnr);
675 down_write(&pci_bus_sem);
676 list_add_tail(&child->node, &parent->children);
677 up_write(&pci_bus_sem);
682 static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
684 struct pci_bus *parent = child->parent;
686 /* Attempts to fix that up are really dangerous unless
687 we're going to re-assign all bus numbers. */
688 if (!pcibios_assign_all_busses())
691 while (parent->parent && parent->busn_res.end < max) {
692 parent->busn_res.end = max;
693 pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);
694 parent = parent->parent;
699 * If it's a bridge, configure it and scan the bus behind it.
700 * For CardBus bridges, we don't scan behind as the devices will
701 * be handled by the bridge driver itself.
703 * We need to process bridges in two passes -- first we scan those
704 * already configured by the BIOS and after we are done with all of
705 * them, we proceed to assigning numbers to the remaining buses in
706 * order to avoid overlaps between old and new bus numbers.
708 int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
710 struct pci_bus *child;
711 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
714 u8 primary, secondary, subordinate;
717 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
718 primary = buses & 0xFF;
719 secondary = (buses >> 8) & 0xFF;
720 subordinate = (buses >> 16) & 0xFF;
722 dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
723 secondary, subordinate, pass);
725 if (!primary && (primary != bus->number) && secondary && subordinate) {
726 dev_warn(&dev->dev, "Primary bus is hard wired to 0\n");
727 primary = bus->number;
730 /* Check if setup is sensible at all */
732 (primary != bus->number || secondary <= bus->number)) {
733 dev_dbg(&dev->dev, "bus configuration invalid, reconfiguring\n");
737 /* Disable MasterAbortMode during probing to avoid reporting
738 of bus errors (in some architectures) */
739 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
740 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
741 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
743 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
744 !is_cardbus && !broken) {
747 * Bus already configured by firmware, process it in the first
748 * pass and just note the configuration.
754 * If we already got to this bus through a different bridge,
755 * don't re-add it. This can happen with the i450NX chipset.
757 * However, we continue to descend down the hierarchy and
758 * scan remaining child buses.
760 child = pci_find_bus(pci_domain_nr(bus), secondary);
762 child = pci_add_new_bus(bus, dev, secondary);
765 child->primary = primary;
766 pci_bus_insert_busn_res(child, secondary, subordinate);
767 child->bridge_ctl = bctl;
770 cmax = pci_scan_child_bus(child);
773 if (child->busn_res.end > max)
774 max = child->busn_res.end;
777 * We need to assign a number to this bus which we always
778 * do in the second pass.
781 if (pcibios_assign_all_busses() || broken)
782 /* Temporarily disable forwarding of the
783 configuration cycles on all bridges in
784 this bus segment to avoid possible
785 conflicts in the second pass between two
786 bridges programmed with overlapping
788 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
794 pci_write_config_word(dev, PCI_STATUS, 0xffff);
796 /* Prevent assigning a bus number that already exists.
797 * This can happen when a bridge is hot-plugged, so in
798 * this case we only re-scan this bus. */
799 child = pci_find_bus(pci_domain_nr(bus), max+1);
801 child = pci_add_new_bus(bus, dev, ++max);
804 pci_bus_insert_busn_res(child, max, 0xff);
806 buses = (buses & 0xff000000)
807 | ((unsigned int)(child->primary) << 0)
808 | ((unsigned int)(child->busn_res.start) << 8)
809 | ((unsigned int)(child->busn_res.end) << 16);
812 * yenta.c forces a secondary latency timer of 176.
813 * Copy that behaviour here.
816 buses &= ~0xff000000;
817 buses |= CARDBUS_LATENCY_TIMER << 24;
821 * We need to blast all three values with a single write.
823 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
826 child->bridge_ctl = bctl;
828 * Adjust subordinate busnr in parent buses.
829 * We do this before scanning for children because
830 * some devices may not be detected if the bios
833 pci_fixup_parent_subordinate_busnr(child, max);
834 /* Now we can scan all subordinate buses... */
835 max = pci_scan_child_bus(child);
837 * now fix it up again since we have found
838 * the real value of max.
840 pci_fixup_parent_subordinate_busnr(child, max);
843 * For CardBus bridges, we leave 4 bus numbers
844 * as cards with a PCI-to-PCI bridge can be
847 for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
848 struct pci_bus *parent = bus;
849 if (pci_find_bus(pci_domain_nr(bus),
852 while (parent->parent) {
853 if ((!pcibios_assign_all_busses()) &&
854 (parent->busn_res.end > max) &&
855 (parent->busn_res.end <= max+i)) {
858 parent = parent->parent;
862 * Often, there are two cardbus bridges
863 * -- try to leave one valid bus number
871 pci_fixup_parent_subordinate_busnr(child, max);
874 * Set the subordinate bus number to its real value.
876 pci_bus_update_busn_res_end(child, max);
877 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
881 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
882 pci_domain_nr(bus), child->number);
884 /* Has only triggered on CardBus, fixup is in yenta_socket */
885 while (bus->parent) {
886 if ((child->busn_res.end > bus->busn_res.end) ||
887 (child->number > bus->busn_res.end) ||
888 (child->number < bus->number) ||
889 (child->busn_res.end < bus->number)) {
890 dev_info(&child->dev, "%pR %s "
891 "hidden behind%s bridge %s %pR\n",
893 (bus->number > child->busn_res.end &&
894 bus->busn_res.end < child->number) ?
895 "wholly" : "partially",
896 bus->self->transparent ? " transparent" : "",
904 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
910 * Read interrupt line and base address registers.
911 * The architecture-dependent code can tweak these, of course.
913 static void pci_read_irq(struct pci_dev *dev)
917 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
920 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
924 void set_pcie_port_type(struct pci_dev *pdev)
929 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
933 pdev->pcie_cap = pos;
934 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
935 pdev->pcie_flags_reg = reg16;
936 pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16);
937 pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
940 void set_pcie_hotplug_bridge(struct pci_dev *pdev)
944 pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32);
945 if (reg32 & PCI_EXP_SLTCAP_HPC)
946 pdev->is_hotplug_bridge = 1;
949 #define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
952 * pci_setup_device - fill in class and map information of a device
953 * @dev: the device structure to fill
955 * Initialize the device structure with information about the device's
956 * vendor,class,memory and IO-space addresses,IRQ lines etc.
957 * Called at initialisation of the PCI subsystem and by CardBus services.
958 * Returns 0 on success and negative if unknown type of device (not normal,
959 * bridge or CardBus).
961 int pci_setup_device(struct pci_dev *dev)
965 struct pci_slot *slot;
967 struct pci_bus_region region;
968 struct resource *res;
970 if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
973 dev->sysdata = dev->bus->sysdata;
974 dev->dev.parent = dev->bus->bridge;
975 dev->dev.bus = &pci_bus_type;
976 dev->hdr_type = hdr_type & 0x7f;
977 dev->multifunction = !!(hdr_type & 0x80);
978 dev->error_state = pci_channel_io_normal;
979 set_pcie_port_type(dev);
981 list_for_each_entry(slot, &dev->bus->slots, list)
982 if (PCI_SLOT(dev->devfn) == slot->number)
985 /* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
986 set this higher, assuming the system even supports it. */
987 dev->dma_mask = 0xffffffff;
989 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
990 dev->bus->number, PCI_SLOT(dev->devfn),
991 PCI_FUNC(dev->devfn));
993 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
994 dev->revision = class & 0xff;
995 dev->class = class >> 8; /* upper 3 bytes */
997 dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %02x class %#08x\n",
998 dev->vendor, dev->device, dev->hdr_type, dev->class);
1000 /* need to have dev->class ready */
1001 dev->cfg_size = pci_cfg_space_size(dev);
1003 /* "Unknown power state" */
1004 dev->current_state = PCI_UNKNOWN;
1006 /* Early fixups, before probing the BARs */
1007 pci_fixup_device(pci_fixup_early, dev);
1008 /* device class may be changed after fixup */
1009 class = dev->class >> 8;
1011 switch (dev->hdr_type) { /* header type */
1012 case PCI_HEADER_TYPE_NORMAL: /* standard header */
1013 if (class == PCI_CLASS_BRIDGE_PCI)
1016 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1017 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1018 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
1021 * Do the ugly legacy mode stuff here rather than broken chip
1022 * quirk code. Legacy mode ATA controllers have fixed
1023 * addresses. These are not always echoed in BAR0-3, and
1024 * BAR0-3 in a few cases contain junk!
1026 if (class == PCI_CLASS_STORAGE_IDE) {
1028 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1029 if ((progif & 1) == 0) {
1030 region.start = 0x1F0;
1032 res = &dev->resource[0];
1033 res->flags = LEGACY_IO_RESOURCE;
1034 pcibios_bus_to_resource(dev, res, ®ion);
1035 region.start = 0x3F6;
1037 res = &dev->resource[1];
1038 res->flags = LEGACY_IO_RESOURCE;
1039 pcibios_bus_to_resource(dev, res, ®ion);
1041 if ((progif & 4) == 0) {
1042 region.start = 0x170;
1044 res = &dev->resource[2];
1045 res->flags = LEGACY_IO_RESOURCE;
1046 pcibios_bus_to_resource(dev, res, ®ion);
1047 region.start = 0x376;
1049 res = &dev->resource[3];
1050 res->flags = LEGACY_IO_RESOURCE;
1051 pcibios_bus_to_resource(dev, res, ®ion);
1056 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1057 if (class != PCI_CLASS_BRIDGE_PCI)
1059 /* The PCI-to-PCI bridge spec requires that subtractive
1060 decoding (i.e. transparent) bridge must have programming
1061 interface code of 0x01. */
1063 dev->transparent = ((dev->class & 0xff) == 1);
1064 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1065 set_pcie_hotplug_bridge(dev);
1066 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1068 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1069 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1073 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1074 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1077 pci_read_bases(dev, 1, 0);
1078 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1079 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1082 default: /* unknown header */
1083 dev_err(&dev->dev, "unknown header type %02x, "
1084 "ignoring device\n", dev->hdr_type);
1088 dev_err(&dev->dev, "ignoring class %#08x (doesn't match header "
1089 "type %02x)\n", dev->class, dev->hdr_type);
1090 dev->class = PCI_CLASS_NOT_DEFINED;
1093 /* We found a fine healthy device, go go go... */
1097 static void pci_release_capabilities(struct pci_dev *dev)
1099 pci_vpd_release(dev);
1100 pci_iov_release(dev);
1101 pci_free_cap_save_buffers(dev);
1105 * pci_release_dev - free a pci device structure when all users of it are finished.
1106 * @dev: device that's been disconnected
1108 * Will be called only by the device core when all users of this pci device are
1111 static void pci_release_dev(struct device *dev)
1113 struct pci_dev *pci_dev;
1115 pci_dev = to_pci_dev(dev);
1116 pci_release_capabilities(pci_dev);
1117 pci_release_of_node(pci_dev);
1122 * pci_cfg_space_size - get the configuration space size of the PCI device.
1125 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1126 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1127 * access it. Maybe we don't have a way to generate extended config space
1128 * accesses, or the device is behind a reverse Express bridge. So we try
1129 * reading the dword at 0x100 which must either be 0 or a valid extended
1130 * capability header.
1132 int pci_cfg_space_size_ext(struct pci_dev *dev)
1135 int pos = PCI_CFG_SPACE_SIZE;
1137 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1139 if (status == 0xffffffff)
1142 return PCI_CFG_SPACE_EXP_SIZE;
1145 return PCI_CFG_SPACE_SIZE;
1148 int pci_cfg_space_size(struct pci_dev *dev)
1154 class = dev->class >> 8;
1155 if (class == PCI_CLASS_BRIDGE_HOST)
1156 return pci_cfg_space_size_ext(dev);
1158 if (!pci_is_pcie(dev)) {
1159 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1163 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1164 if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
1168 return pci_cfg_space_size_ext(dev);
1171 return PCI_CFG_SPACE_SIZE;
1174 static void pci_release_bus_bridge_dev(struct device *dev)
1176 struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
1178 if (bridge->release_fn)
1179 bridge->release_fn(bridge);
1181 pci_free_resource_list(&bridge->windows);
1186 struct pci_dev *alloc_pci_dev(void)
1188 struct pci_dev *dev;
1190 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
1194 INIT_LIST_HEAD(&dev->bus_list);
1198 EXPORT_SYMBOL(alloc_pci_dev);
1200 bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
1205 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1208 /* some broken boards return 0 or ~0 if a slot is empty: */
1209 if (*l == 0xffffffff || *l == 0x00000000 ||
1210 *l == 0x0000ffff || *l == 0xffff0000)
1213 /* Configuration request Retry Status */
1214 while (*l == 0xffff0001) {
1220 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1222 /* Card hasn't responded in 60 seconds? Must be stuck. */
1223 if (delay > crs_timeout) {
1224 printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not "
1225 "responding\n", pci_domain_nr(bus),
1226 bus->number, PCI_SLOT(devfn),
1234 EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
1237 * Read the config data for a PCI device, sanity-check it
1238 * and fill in the dev structure...
1240 static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
1242 struct pci_dev *dev;
1245 if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
1248 dev = alloc_pci_dev();
1254 dev->vendor = l & 0xffff;
1255 dev->device = (l >> 16) & 0xffff;
1257 pci_set_of_node(dev);
1259 if (pci_setup_device(dev)) {
1267 static void pci_init_capabilities(struct pci_dev *dev)
1269 /* MSI/MSI-X list */
1270 pci_msi_init_pci_dev(dev);
1272 /* Buffers for saving PCIe and PCI-X capabilities */
1273 pci_allocate_cap_save_buffers(dev);
1275 /* Power Management */
1277 platform_pci_wakeup_init(dev);
1279 /* Vital Product Data */
1280 pci_vpd_pci22_init(dev);
1282 /* Alternative Routing-ID Forwarding */
1283 pci_enable_ari(dev);
1285 /* Single Root I/O Virtualization */
1288 /* Enable ACS P2P upstream forwarding */
1289 pci_enable_acs(dev);
1292 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
1294 device_initialize(&dev->dev);
1295 dev->dev.release = pci_release_dev;
1298 dev->dev.dma_mask = &dev->dma_mask;
1299 dev->dev.dma_parms = &dev->dma_parms;
1300 dev->dev.coherent_dma_mask = 0xffffffffull;
1302 pci_set_dma_max_seg_size(dev, 65536);
1303 pci_set_dma_seg_boundary(dev, 0xffffffff);
1305 /* Fix up broken headers */
1306 pci_fixup_device(pci_fixup_header, dev);
1308 /* moved out from quirk header fixup code */
1309 pci_reassigndev_resource_alignment(dev);
1311 /* Clear the state_saved flag. */
1312 dev->state_saved = false;
1314 /* Initialize various capabilities */
1315 pci_init_capabilities(dev);
1318 * Add the device to our list of discovered devices
1319 * and the bus list for fixup functions, etc.
1321 down_write(&pci_bus_sem);
1322 list_add_tail(&dev->bus_list, &bus->devices);
1323 up_write(&pci_bus_sem);
1326 struct pci_dev *__ref pci_scan_single_device(struct pci_bus *bus, int devfn)
1328 struct pci_dev *dev;
1330 dev = pci_get_slot(bus, devfn);
1336 dev = pci_scan_device(bus, devfn);
1340 pci_device_add(dev, bus);
1344 EXPORT_SYMBOL(pci_scan_single_device);
1346 static unsigned next_ari_fn(struct pci_dev *dev, unsigned fn)
1349 unsigned pos, next_fn;
1354 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1357 pci_read_config_word(dev, pos + 4, &cap);
1364 static unsigned next_trad_fn(struct pci_dev *dev, unsigned fn)
1366 return (fn + 1) % 8;
1369 static unsigned no_next_fn(struct pci_dev *dev, unsigned fn)
1374 static int only_one_child(struct pci_bus *bus)
1376 struct pci_dev *parent = bus->self;
1378 if (!parent || !pci_is_pcie(parent))
1380 if (pci_pcie_type(parent) == PCI_EXP_TYPE_ROOT_PORT)
1382 if (pci_pcie_type(parent) == PCI_EXP_TYPE_DOWNSTREAM &&
1383 !pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
1389 * pci_scan_slot - scan a PCI slot on a bus for devices.
1390 * @bus: PCI bus to scan
1391 * @devfn: slot number to scan (must have zero function.)
1393 * Scan a PCI slot on the specified PCI bus for devices, adding
1394 * discovered devices to the @bus->devices list. New devices
1395 * will not have is_added set.
1397 * Returns the number of new devices found.
1399 int pci_scan_slot(struct pci_bus *bus, int devfn)
1401 unsigned fn, nr = 0;
1402 struct pci_dev *dev;
1403 unsigned (*next_fn)(struct pci_dev *, unsigned) = no_next_fn;
1405 if (only_one_child(bus) && (devfn > 0))
1406 return 0; /* Already scanned the entire slot */
1408 dev = pci_scan_single_device(bus, devfn);
1414 if (pci_ari_enabled(bus))
1415 next_fn = next_ari_fn;
1416 else if (dev->multifunction)
1417 next_fn = next_trad_fn;
1419 for (fn = next_fn(dev, 0); fn > 0; fn = next_fn(dev, fn)) {
1420 dev = pci_scan_single_device(bus, devfn + fn);
1424 dev->multifunction = 1;
1428 /* only one slot has pcie device */
1429 if (bus->self && nr)
1430 pcie_aspm_init_link_state(bus->self);
1435 static int pcie_find_smpss(struct pci_dev *dev, void *data)
1439 if (!pci_is_pcie(dev))
1442 /* For PCIE hotplug enabled slots not connected directly to a
1443 * PCI-E root port, there can be problems when hotplugging
1444 * devices. This is due to the possibility of hotplugging a
1445 * device into the fabric with a smaller MPS that the devices
1446 * currently running have configured. Modifying the MPS on the
1447 * running devices could cause a fatal bus error due to an
1448 * incoming frame being larger than the newly configured MPS.
1449 * To work around this, the MPS for the entire fabric must be
1450 * set to the minimum size. Any devices hotplugged into this
1451 * fabric will have the minimum MPS set. If the PCI hotplug
1452 * slot is directly connected to the root port and there are not
1453 * other devices on the fabric (which seems to be the most
1454 * common case), then this is not an issue and MPS discovery
1455 * will occur as normal.
1457 if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) ||
1459 pci_pcie_type(dev->bus->self) != PCI_EXP_TYPE_ROOT_PORT)))
1462 if (*smpss > dev->pcie_mpss)
1463 *smpss = dev->pcie_mpss;
1468 static void pcie_write_mps(struct pci_dev *dev, int mps)
1472 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
1473 mps = 128 << dev->pcie_mpss;
1475 if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
1477 /* For "Performance", the assumption is made that
1478 * downstream communication will never be larger than
1479 * the MRRS. So, the MPS only needs to be configured
1480 * for the upstream communication. This being the case,
1481 * walk from the top down and set the MPS of the child
1482 * to that of the parent bus.
1484 * Configure the device MPS with the smaller of the
1485 * device MPSS or the bridge MPS (which is assumed to be
1486 * properly configured at this point to the largest
1487 * allowable MPS based on its parent bus).
1489 mps = min(mps, pcie_get_mps(dev->bus->self));
1492 rc = pcie_set_mps(dev, mps);
1494 dev_err(&dev->dev, "Failed attempting to set the MPS\n");
1497 static void pcie_write_mrrs(struct pci_dev *dev)
1501 /* In the "safe" case, do not configure the MRRS. There appear to be
1502 * issues with setting MRRS to 0 on a number of devices.
1504 if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
1507 /* For Max performance, the MRRS must be set to the largest supported
1508 * value. However, it cannot be configured larger than the MPS the
1509 * device or the bus can support. This should already be properly
1510 * configured by a prior call to pcie_write_mps.
1512 mrrs = pcie_get_mps(dev);
1514 /* MRRS is a R/W register. Invalid values can be written, but a
1515 * subsequent read will verify if the value is acceptable or not.
1516 * If the MRRS value provided is not acceptable (e.g., too large),
1517 * shrink the value until it is acceptable to the HW.
1519 while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
1520 rc = pcie_set_readrq(dev, mrrs);
1524 dev_warn(&dev->dev, "Failed attempting to set the MRRS\n");
1529 dev_err(&dev->dev, "MRRS was unable to be configured with a "
1530 "safe value. If problems are experienced, try running "
1531 "with pci=pcie_bus_safe.\n");
1534 static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
1538 if (!pci_is_pcie(dev))
1541 mps = 128 << *(u8 *)data;
1542 orig_mps = pcie_get_mps(dev);
1544 pcie_write_mps(dev, mps);
1545 pcie_write_mrrs(dev);
1547 dev_info(&dev->dev, "PCI-E Max Payload Size set to %4d/%4d (was %4d), "
1548 "Max Read Rq %4d\n", pcie_get_mps(dev), 128 << dev->pcie_mpss,
1549 orig_mps, pcie_get_readrq(dev));
1554 /* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down,
1555 * parents then children fashion. If this changes, then this code will not
1558 void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss)
1562 if (!pci_is_pcie(bus->self))
1565 if (pcie_bus_config == PCIE_BUS_TUNE_OFF)
1568 /* FIXME - Peer to peer DMA is possible, though the endpoint would need
1569 * to be aware to the MPS of the destination. To work around this,
1570 * simply force the MPS of the entire system to the smallest possible.
1572 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
1575 if (pcie_bus_config == PCIE_BUS_SAFE) {
1578 pcie_find_smpss(bus->self, &smpss);
1579 pci_walk_bus(bus, pcie_find_smpss, &smpss);
1582 pcie_bus_configure_set(bus->self, &smpss);
1583 pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
1585 EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
1587 unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
1589 unsigned int devfn, pass, max = bus->busn_res.start;
1590 struct pci_dev *dev;
1592 dev_dbg(&bus->dev, "scanning bus\n");
1594 /* Go find them, Rover! */
1595 for (devfn = 0; devfn < 0x100; devfn += 8)
1596 pci_scan_slot(bus, devfn);
1598 /* Reserve buses for SR-IOV capability. */
1599 max += pci_iov_bus_range(bus);
1602 * After performing arch-dependent fixup of the bus, look behind
1603 * all PCI-to-PCI bridges on this bus.
1605 if (!bus->is_added) {
1606 dev_dbg(&bus->dev, "fixups for bus\n");
1607 pcibios_fixup_bus(bus);
1608 if (pci_is_root_bus(bus))
1612 for (pass=0; pass < 2; pass++)
1613 list_for_each_entry(dev, &bus->devices, bus_list) {
1614 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
1615 dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
1616 max = pci_scan_bridge(bus, dev, max, pass);
1620 * We've scanned the bus and so we know all about what's on
1621 * the other side of any bridges that may be on this bus plus
1624 * Return how far we've got finding sub-buses.
1626 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
1630 struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
1631 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1634 struct pci_host_bridge *bridge;
1635 struct pci_bus *b, *b2;
1636 struct pci_host_bridge_window *window, *n;
1637 struct resource *res;
1638 resource_size_t offset;
1643 b = pci_alloc_bus();
1647 b->sysdata = sysdata;
1649 b2 = pci_find_bus(pci_domain_nr(b), bus);
1651 /* If we already got to this bus through a different bridge, ignore it */
1652 dev_dbg(&b2->dev, "bus already known\n");
1656 bridge = pci_alloc_host_bridge(b);
1660 bridge->dev.parent = parent;
1661 bridge->dev.release = pci_release_bus_bridge_dev;
1662 dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
1663 error = device_register(&bridge->dev);
1665 goto bridge_dev_reg_err;
1666 b->bridge = get_device(&bridge->dev);
1667 device_enable_async_suspend(b->bridge);
1668 pci_set_bus_of_node(b);
1671 set_dev_node(b->bridge, pcibus_to_node(b));
1673 b->dev.class = &pcibus_class;
1674 b->dev.parent = b->bridge;
1675 dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
1676 error = device_register(&b->dev);
1678 goto class_dev_reg_err;
1680 /* Create legacy_io and legacy_mem files for this bus */
1681 pci_create_legacy_files(b);
1683 b->number = b->busn_res.start = bus;
1686 dev_info(parent, "PCI host bridge to bus %s\n", dev_name(&b->dev));
1688 printk(KERN_INFO "PCI host bridge to bus %s\n", dev_name(&b->dev));
1690 /* Add initial resources to the bus */
1691 list_for_each_entry_safe(window, n, resources, list) {
1692 list_move_tail(&window->list, &bridge->windows);
1694 offset = window->offset;
1695 if (res->flags & IORESOURCE_BUS)
1696 pci_bus_insert_busn_res(b, bus, res->end);
1698 pci_bus_add_resource(b, res, 0);
1700 if (resource_type(res) == IORESOURCE_IO)
1701 fmt = " (bus address [%#06llx-%#06llx])";
1703 fmt = " (bus address [%#010llx-%#010llx])";
1704 snprintf(bus_addr, sizeof(bus_addr), fmt,
1705 (unsigned long long) (res->start - offset),
1706 (unsigned long long) (res->end - offset));
1709 dev_info(&b->dev, "root bus resource %pR%s\n", res, bus_addr);
1712 down_write(&pci_bus_sem);
1713 list_add_tail(&b->node, &pci_root_buses);
1714 up_write(&pci_bus_sem);
1719 put_device(&bridge->dev);
1720 device_unregister(&bridge->dev);
1728 int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
1730 struct resource *res = &b->busn_res;
1731 struct resource *parent_res, *conflict;
1735 res->flags = IORESOURCE_BUS;
1737 if (!pci_is_root_bus(b))
1738 parent_res = &b->parent->busn_res;
1740 parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
1741 res->flags |= IORESOURCE_PCI_FIXED;
1744 conflict = insert_resource_conflict(parent_res, res);
1747 dev_printk(KERN_DEBUG, &b->dev,
1748 "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
1749 res, pci_is_root_bus(b) ? "domain " : "",
1750 parent_res, conflict->name, conflict);
1752 dev_printk(KERN_DEBUG, &b->dev,
1753 "busn_res: %pR is inserted under %s%pR\n",
1754 res, pci_is_root_bus(b) ? "domain " : "",
1757 return conflict == NULL;
1760 int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
1762 struct resource *res = &b->busn_res;
1763 struct resource old_res = *res;
1764 resource_size_t size;
1767 if (res->start > bus_max)
1770 size = bus_max - res->start + 1;
1771 ret = adjust_resource(res, res->start, size);
1772 dev_printk(KERN_DEBUG, &b->dev,
1773 "busn_res: %pR end %s updated to %02x\n",
1774 &old_res, ret ? "can not be" : "is", bus_max);
1776 if (!ret && !res->parent)
1777 pci_bus_insert_busn_res(b, res->start, res->end);
1782 void pci_bus_release_busn_res(struct pci_bus *b)
1784 struct resource *res = &b->busn_res;
1787 if (!res->flags || !res->parent)
1790 ret = release_resource(res);
1791 dev_printk(KERN_DEBUG, &b->dev,
1792 "busn_res: %pR %s released\n",
1793 res, ret ? "can not be" : "is");
1796 struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
1797 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1799 struct pci_host_bridge_window *window;
1804 list_for_each_entry(window, resources, list)
1805 if (window->res->flags & IORESOURCE_BUS) {
1810 b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
1816 "No busn resource found for root bus, will use [bus %02x-ff]\n",
1818 pci_bus_insert_busn_res(b, bus, 255);
1821 max = pci_scan_child_bus(b);
1824 pci_bus_update_busn_res_end(b, max);
1826 pci_bus_add_devices(b);
1829 EXPORT_SYMBOL(pci_scan_root_bus);
1831 /* Deprecated; use pci_scan_root_bus() instead */
1832 struct pci_bus * __devinit pci_scan_bus_parented(struct device *parent,
1833 int bus, struct pci_ops *ops, void *sysdata)
1835 LIST_HEAD(resources);
1838 pci_add_resource(&resources, &ioport_resource);
1839 pci_add_resource(&resources, &iomem_resource);
1840 pci_add_resource(&resources, &busn_resource);
1841 b = pci_create_root_bus(parent, bus, ops, sysdata, &resources);
1843 pci_scan_child_bus(b);
1845 pci_free_resource_list(&resources);
1848 EXPORT_SYMBOL(pci_scan_bus_parented);
1850 struct pci_bus * __devinit pci_scan_bus(int bus, struct pci_ops *ops,
1853 LIST_HEAD(resources);
1856 pci_add_resource(&resources, &ioport_resource);
1857 pci_add_resource(&resources, &iomem_resource);
1858 pci_add_resource(&resources, &busn_resource);
1859 b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
1861 pci_scan_child_bus(b);
1862 pci_bus_add_devices(b);
1864 pci_free_resource_list(&resources);
1868 EXPORT_SYMBOL(pci_scan_bus);
1870 #ifdef CONFIG_HOTPLUG
1872 * pci_rescan_bus_bridge_resize - scan a PCI bus for devices.
1873 * @bridge: PCI bridge for the bus to scan
1875 * Scan a PCI bus and child buses for new devices, add them,
1876 * and enable them, resizing bridge mmio/io resource if necessary
1877 * and possible. The caller must ensure the child devices are already
1878 * removed for resizing to occur.
1880 * Returns the max number of subordinate bus discovered.
1882 unsigned int __ref pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
1885 struct pci_bus *bus = bridge->subordinate;
1887 max = pci_scan_child_bus(bus);
1889 pci_assign_unassigned_bridge_resources(bridge);
1891 pci_bus_add_devices(bus);
1896 EXPORT_SYMBOL(pci_add_new_bus);
1897 EXPORT_SYMBOL(pci_scan_slot);
1898 EXPORT_SYMBOL(pci_scan_bridge);
1899 EXPORT_SYMBOL_GPL(pci_scan_child_bus);
1902 static int __init pci_sort_bf_cmp(const struct device *d_a, const struct device *d_b)
1904 const struct pci_dev *a = to_pci_dev(d_a);
1905 const struct pci_dev *b = to_pci_dev(d_b);
1907 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
1908 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
1910 if (a->bus->number < b->bus->number) return -1;
1911 else if (a->bus->number > b->bus->number) return 1;
1913 if (a->devfn < b->devfn) return -1;
1914 else if (a->devfn > b->devfn) return 1;
1919 void __init pci_sort_breadthfirst(void)
1921 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);