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 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 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 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 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 & PCI_EXP_LNKSTA_CLS];
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;
583 pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
586 if (status & PCI_X_SSTATUS_533MHZ) {
587 max = PCI_SPEED_133MHz_PCIX_533;
588 } else if (status & PCI_X_SSTATUS_266MHZ) {
589 max = PCI_SPEED_133MHz_PCIX_266;
590 } else if (status & PCI_X_SSTATUS_133MHZ) {
591 if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2) {
592 max = PCI_SPEED_133MHz_PCIX_ECC;
594 max = PCI_SPEED_133MHz_PCIX;
597 max = PCI_SPEED_66MHz_PCIX;
600 bus->max_bus_speed = max;
601 bus->cur_bus_speed = pcix_bus_speed[
602 (status & PCI_X_SSTATUS_FREQ) >> 6];
607 pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
612 pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
613 bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
615 pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
616 pcie_update_link_speed(bus, linksta);
621 static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
622 struct pci_dev *bridge, int busnr)
624 struct pci_bus *child;
629 * Allocate a new bus, and inherit stuff from the parent..
631 child = pci_alloc_bus();
635 child->parent = parent;
636 child->ops = parent->ops;
637 child->sysdata = parent->sysdata;
638 child->bus_flags = parent->bus_flags;
640 /* initialize some portions of the bus device, but don't register it
641 * now as the parent is not properly set up yet.
643 child->dev.class = &pcibus_class;
644 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
647 * Set up the primary, secondary and subordinate
650 child->number = child->busn_res.start = busnr;
651 child->primary = parent->busn_res.start;
652 child->busn_res.end = 0xff;
655 child->dev.parent = parent->bridge;
659 child->self = bridge;
660 child->bridge = get_device(&bridge->dev);
661 child->dev.parent = child->bridge;
662 pci_set_bus_of_node(child);
663 pci_set_bus_speed(child);
665 /* Set up default resource pointers and names.. */
666 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
667 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
668 child->resource[i]->name = child->name;
670 bridge->subordinate = child;
673 ret = device_register(&child->dev);
676 pcibios_add_bus(child);
678 /* Create legacy_io and legacy_mem files for this bus */
679 pci_create_legacy_files(child);
684 struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr)
686 struct pci_bus *child;
688 child = pci_alloc_child_bus(parent, dev, busnr);
690 down_write(&pci_bus_sem);
691 list_add_tail(&child->node, &parent->children);
692 up_write(&pci_bus_sem);
697 static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
699 struct pci_bus *parent = child->parent;
701 /* Attempts to fix that up are really dangerous unless
702 we're going to re-assign all bus numbers. */
703 if (!pcibios_assign_all_busses())
706 while (parent->parent && parent->busn_res.end < max) {
707 parent->busn_res.end = max;
708 pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);
709 parent = parent->parent;
714 * If it's a bridge, configure it and scan the bus behind it.
715 * For CardBus bridges, we don't scan behind as the devices will
716 * be handled by the bridge driver itself.
718 * We need to process bridges in two passes -- first we scan those
719 * already configured by the BIOS and after we are done with all of
720 * them, we proceed to assigning numbers to the remaining buses in
721 * order to avoid overlaps between old and new bus numbers.
723 int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
725 struct pci_bus *child;
726 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
729 u8 primary, secondary, subordinate;
732 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
733 primary = buses & 0xFF;
734 secondary = (buses >> 8) & 0xFF;
735 subordinate = (buses >> 16) & 0xFF;
737 dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
738 secondary, subordinate, pass);
740 if (!primary && (primary != bus->number) && secondary && subordinate) {
741 dev_warn(&dev->dev, "Primary bus is hard wired to 0\n");
742 primary = bus->number;
745 /* Check if setup is sensible at all */
747 (primary != bus->number || secondary <= bus->number ||
748 secondary > subordinate)) {
749 dev_info(&dev->dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
750 secondary, subordinate);
754 /* Disable MasterAbortMode during probing to avoid reporting
755 of bus errors (in some architectures) */
756 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
757 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
758 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
760 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
761 !is_cardbus && !broken) {
764 * Bus already configured by firmware, process it in the first
765 * pass and just note the configuration.
771 * If we already got to this bus through a different bridge,
772 * don't re-add it. This can happen with the i450NX chipset.
774 * However, we continue to descend down the hierarchy and
775 * scan remaining child buses.
777 child = pci_find_bus(pci_domain_nr(bus), secondary);
779 child = pci_add_new_bus(bus, dev, secondary);
782 child->primary = primary;
783 pci_bus_insert_busn_res(child, secondary, subordinate);
784 child->bridge_ctl = bctl;
787 cmax = pci_scan_child_bus(child);
790 if (child->busn_res.end > max)
791 max = child->busn_res.end;
794 * We need to assign a number to this bus which we always
795 * do in the second pass.
798 if (pcibios_assign_all_busses() || broken)
799 /* Temporarily disable forwarding of the
800 configuration cycles on all bridges in
801 this bus segment to avoid possible
802 conflicts in the second pass between two
803 bridges programmed with overlapping
805 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
811 pci_write_config_word(dev, PCI_STATUS, 0xffff);
813 /* Prevent assigning a bus number that already exists.
814 * This can happen when a bridge is hot-plugged, so in
815 * this case we only re-scan this bus. */
816 child = pci_find_bus(pci_domain_nr(bus), max+1);
818 child = pci_add_new_bus(bus, dev, ++max);
821 pci_bus_insert_busn_res(child, max, 0xff);
823 buses = (buses & 0xff000000)
824 | ((unsigned int)(child->primary) << 0)
825 | ((unsigned int)(child->busn_res.start) << 8)
826 | ((unsigned int)(child->busn_res.end) << 16);
829 * yenta.c forces a secondary latency timer of 176.
830 * Copy that behaviour here.
833 buses &= ~0xff000000;
834 buses |= CARDBUS_LATENCY_TIMER << 24;
838 * We need to blast all three values with a single write.
840 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
843 child->bridge_ctl = bctl;
845 * Adjust subordinate busnr in parent buses.
846 * We do this before scanning for children because
847 * some devices may not be detected if the bios
850 pci_fixup_parent_subordinate_busnr(child, max);
851 /* Now we can scan all subordinate buses... */
852 max = pci_scan_child_bus(child);
854 * now fix it up again since we have found
855 * the real value of max.
857 pci_fixup_parent_subordinate_busnr(child, max);
860 * For CardBus bridges, we leave 4 bus numbers
861 * as cards with a PCI-to-PCI bridge can be
864 for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
865 struct pci_bus *parent = bus;
866 if (pci_find_bus(pci_domain_nr(bus),
869 while (parent->parent) {
870 if ((!pcibios_assign_all_busses()) &&
871 (parent->busn_res.end > max) &&
872 (parent->busn_res.end <= max+i)) {
875 parent = parent->parent;
879 * Often, there are two cardbus bridges
880 * -- try to leave one valid bus number
888 pci_fixup_parent_subordinate_busnr(child, max);
891 * Set the subordinate bus number to its real value.
893 pci_bus_update_busn_res_end(child, max);
894 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
898 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
899 pci_domain_nr(bus), child->number);
901 /* Has only triggered on CardBus, fixup is in yenta_socket */
902 while (bus->parent) {
903 if ((child->busn_res.end > bus->busn_res.end) ||
904 (child->number > bus->busn_res.end) ||
905 (child->number < bus->number) ||
906 (child->busn_res.end < bus->number)) {
907 dev_info(&child->dev, "%pR %s "
908 "hidden behind%s bridge %s %pR\n",
910 (bus->number > child->busn_res.end &&
911 bus->busn_res.end < child->number) ?
912 "wholly" : "partially",
913 bus->self->transparent ? " transparent" : "",
921 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
927 * Read interrupt line and base address registers.
928 * The architecture-dependent code can tweak these, of course.
930 static void pci_read_irq(struct pci_dev *dev)
934 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
937 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
941 void set_pcie_port_type(struct pci_dev *pdev)
946 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
950 pdev->pcie_cap = pos;
951 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
952 pdev->pcie_flags_reg = reg16;
953 pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16);
954 pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
957 void set_pcie_hotplug_bridge(struct pci_dev *pdev)
961 pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32);
962 if (reg32 & PCI_EXP_SLTCAP_HPC)
963 pdev->is_hotplug_bridge = 1;
966 #define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
969 * pci_setup_device - fill in class and map information of a device
970 * @dev: the device structure to fill
972 * Initialize the device structure with information about the device's
973 * vendor,class,memory and IO-space addresses,IRQ lines etc.
974 * Called at initialisation of the PCI subsystem and by CardBus services.
975 * Returns 0 on success and negative if unknown type of device (not normal,
976 * bridge or CardBus).
978 int pci_setup_device(struct pci_dev *dev)
982 struct pci_slot *slot;
984 struct pci_bus_region region;
985 struct resource *res;
987 if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
990 dev->sysdata = dev->bus->sysdata;
991 dev->dev.parent = dev->bus->bridge;
992 dev->dev.bus = &pci_bus_type;
993 dev->hdr_type = hdr_type & 0x7f;
994 dev->multifunction = !!(hdr_type & 0x80);
995 dev->error_state = pci_channel_io_normal;
996 set_pcie_port_type(dev);
998 list_for_each_entry(slot, &dev->bus->slots, list)
999 if (PCI_SLOT(dev->devfn) == slot->number)
1002 /* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
1003 set this higher, assuming the system even supports it. */
1004 dev->dma_mask = 0xffffffff;
1006 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
1007 dev->bus->number, PCI_SLOT(dev->devfn),
1008 PCI_FUNC(dev->devfn));
1010 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
1011 dev->revision = class & 0xff;
1012 dev->class = class >> 8; /* upper 3 bytes */
1014 dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %02x class %#08x\n",
1015 dev->vendor, dev->device, dev->hdr_type, dev->class);
1017 /* need to have dev->class ready */
1018 dev->cfg_size = pci_cfg_space_size(dev);
1020 /* "Unknown power state" */
1021 dev->current_state = PCI_UNKNOWN;
1023 /* Early fixups, before probing the BARs */
1024 pci_fixup_device(pci_fixup_early, dev);
1025 /* device class may be changed after fixup */
1026 class = dev->class >> 8;
1028 switch (dev->hdr_type) { /* header type */
1029 case PCI_HEADER_TYPE_NORMAL: /* standard header */
1030 if (class == PCI_CLASS_BRIDGE_PCI)
1033 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1034 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1035 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
1038 * Do the ugly legacy mode stuff here rather than broken chip
1039 * quirk code. Legacy mode ATA controllers have fixed
1040 * addresses. These are not always echoed in BAR0-3, and
1041 * BAR0-3 in a few cases contain junk!
1043 if (class == PCI_CLASS_STORAGE_IDE) {
1045 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1046 if ((progif & 1) == 0) {
1047 region.start = 0x1F0;
1049 res = &dev->resource[0];
1050 res->flags = LEGACY_IO_RESOURCE;
1051 pcibios_bus_to_resource(dev, res, ®ion);
1052 region.start = 0x3F6;
1054 res = &dev->resource[1];
1055 res->flags = LEGACY_IO_RESOURCE;
1056 pcibios_bus_to_resource(dev, res, ®ion);
1058 if ((progif & 4) == 0) {
1059 region.start = 0x170;
1061 res = &dev->resource[2];
1062 res->flags = LEGACY_IO_RESOURCE;
1063 pcibios_bus_to_resource(dev, res, ®ion);
1064 region.start = 0x376;
1066 res = &dev->resource[3];
1067 res->flags = LEGACY_IO_RESOURCE;
1068 pcibios_bus_to_resource(dev, res, ®ion);
1073 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1074 if (class != PCI_CLASS_BRIDGE_PCI)
1076 /* The PCI-to-PCI bridge spec requires that subtractive
1077 decoding (i.e. transparent) bridge must have programming
1078 interface code of 0x01. */
1080 dev->transparent = ((dev->class & 0xff) == 1);
1081 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1082 set_pcie_hotplug_bridge(dev);
1083 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1085 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1086 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1090 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1091 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1094 pci_read_bases(dev, 1, 0);
1095 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1096 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1099 default: /* unknown header */
1100 dev_err(&dev->dev, "unknown header type %02x, "
1101 "ignoring device\n", dev->hdr_type);
1105 dev_err(&dev->dev, "ignoring class %#08x (doesn't match header "
1106 "type %02x)\n", dev->class, dev->hdr_type);
1107 dev->class = PCI_CLASS_NOT_DEFINED;
1110 /* We found a fine healthy device, go go go... */
1114 static void pci_release_capabilities(struct pci_dev *dev)
1116 pci_vpd_release(dev);
1117 pci_iov_release(dev);
1118 pci_free_cap_save_buffers(dev);
1122 * pci_release_dev - free a pci device structure when all users of it are finished.
1123 * @dev: device that's been disconnected
1125 * Will be called only by the device core when all users of this pci device are
1128 static void pci_release_dev(struct device *dev)
1130 struct pci_dev *pci_dev;
1132 pci_dev = to_pci_dev(dev);
1133 pci_release_capabilities(pci_dev);
1134 pci_release_of_node(pci_dev);
1139 * pci_cfg_space_size - get the configuration space size of the PCI device.
1142 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1143 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1144 * access it. Maybe we don't have a way to generate extended config space
1145 * accesses, or the device is behind a reverse Express bridge. So we try
1146 * reading the dword at 0x100 which must either be 0 or a valid extended
1147 * capability header.
1149 int pci_cfg_space_size_ext(struct pci_dev *dev)
1152 int pos = PCI_CFG_SPACE_SIZE;
1154 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1156 if (status == 0xffffffff)
1159 return PCI_CFG_SPACE_EXP_SIZE;
1162 return PCI_CFG_SPACE_SIZE;
1165 int pci_cfg_space_size(struct pci_dev *dev)
1171 class = dev->class >> 8;
1172 if (class == PCI_CLASS_BRIDGE_HOST)
1173 return pci_cfg_space_size_ext(dev);
1175 if (!pci_is_pcie(dev)) {
1176 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1180 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1181 if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
1185 return pci_cfg_space_size_ext(dev);
1188 return PCI_CFG_SPACE_SIZE;
1191 static void pci_release_bus_bridge_dev(struct device *dev)
1193 struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
1195 if (bridge->release_fn)
1196 bridge->release_fn(bridge);
1198 pci_free_resource_list(&bridge->windows);
1203 struct pci_dev *alloc_pci_dev(void)
1205 struct pci_dev *dev;
1207 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
1211 INIT_LIST_HEAD(&dev->bus_list);
1212 dev->dev.type = &pci_dev_type;
1216 EXPORT_SYMBOL(alloc_pci_dev);
1218 bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
1223 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1226 /* some broken boards return 0 or ~0 if a slot is empty: */
1227 if (*l == 0xffffffff || *l == 0x00000000 ||
1228 *l == 0x0000ffff || *l == 0xffff0000)
1231 /* Configuration request Retry Status */
1232 while (*l == 0xffff0001) {
1238 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1240 /* Card hasn't responded in 60 seconds? Must be stuck. */
1241 if (delay > crs_timeout) {
1242 printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not "
1243 "responding\n", pci_domain_nr(bus),
1244 bus->number, PCI_SLOT(devfn),
1252 EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
1255 * Read the config data for a PCI device, sanity-check it
1256 * and fill in the dev structure...
1258 static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
1260 struct pci_dev *dev;
1263 if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
1266 dev = alloc_pci_dev();
1272 dev->vendor = l & 0xffff;
1273 dev->device = (l >> 16) & 0xffff;
1275 pci_set_of_node(dev);
1277 if (pci_setup_device(dev)) {
1285 static void pci_init_capabilities(struct pci_dev *dev)
1287 /* MSI/MSI-X list */
1288 pci_msi_init_pci_dev(dev);
1290 /* Buffers for saving PCIe and PCI-X capabilities */
1291 pci_allocate_cap_save_buffers(dev);
1293 /* Power Management */
1296 /* Vital Product Data */
1297 pci_vpd_pci22_init(dev);
1299 /* Alternative Routing-ID Forwarding */
1300 pci_configure_ari(dev);
1302 /* Single Root I/O Virtualization */
1305 /* Enable ACS P2P upstream forwarding */
1306 pci_enable_acs(dev);
1309 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
1313 device_initialize(&dev->dev);
1314 dev->dev.release = pci_release_dev;
1316 set_dev_node(&dev->dev, pcibus_to_node(bus));
1317 dev->dev.dma_mask = &dev->dma_mask;
1318 dev->dev.dma_parms = &dev->dma_parms;
1319 dev->dev.coherent_dma_mask = 0xffffffffull;
1321 pci_set_dma_max_seg_size(dev, 65536);
1322 pci_set_dma_seg_boundary(dev, 0xffffffff);
1324 /* Fix up broken headers */
1325 pci_fixup_device(pci_fixup_header, dev);
1327 /* moved out from quirk header fixup code */
1328 pci_reassigndev_resource_alignment(dev);
1330 /* Clear the state_saved flag. */
1331 dev->state_saved = false;
1333 /* Initialize various capabilities */
1334 pci_init_capabilities(dev);
1337 * Add the device to our list of discovered devices
1338 * and the bus list for fixup functions, etc.
1340 down_write(&pci_bus_sem);
1341 list_add_tail(&dev->bus_list, &bus->devices);
1342 up_write(&pci_bus_sem);
1344 ret = pcibios_add_device(dev);
1347 /* Notifier could use PCI capabilities */
1348 dev->match_driver = false;
1349 ret = device_add(&dev->dev);
1352 pci_proc_attach_device(dev);
1355 struct pci_dev *__ref pci_scan_single_device(struct pci_bus *bus, int devfn)
1357 struct pci_dev *dev;
1359 dev = pci_get_slot(bus, devfn);
1365 dev = pci_scan_device(bus, devfn);
1369 pci_device_add(dev, bus);
1373 EXPORT_SYMBOL(pci_scan_single_device);
1375 static unsigned next_fn(struct pci_bus *bus, struct pci_dev *dev, unsigned fn)
1381 if (pci_ari_enabled(bus)) {
1384 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1388 pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap);
1389 next_fn = PCI_ARI_CAP_NFN(cap);
1391 return 0; /* protect against malformed list */
1396 /* dev may be NULL for non-contiguous multifunction devices */
1397 if (!dev || dev->multifunction)
1398 return (fn + 1) % 8;
1403 static int only_one_child(struct pci_bus *bus)
1405 struct pci_dev *parent = bus->self;
1407 if (!parent || !pci_is_pcie(parent))
1409 if (pci_pcie_type(parent) == PCI_EXP_TYPE_ROOT_PORT)
1411 if (pci_pcie_type(parent) == PCI_EXP_TYPE_DOWNSTREAM &&
1412 !pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
1418 * pci_scan_slot - scan a PCI slot on a bus for devices.
1419 * @bus: PCI bus to scan
1420 * @devfn: slot number to scan (must have zero function.)
1422 * Scan a PCI slot on the specified PCI bus for devices, adding
1423 * discovered devices to the @bus->devices list. New devices
1424 * will not have is_added set.
1426 * Returns the number of new devices found.
1428 int pci_scan_slot(struct pci_bus *bus, int devfn)
1430 unsigned fn, nr = 0;
1431 struct pci_dev *dev;
1433 if (only_one_child(bus) && (devfn > 0))
1434 return 0; /* Already scanned the entire slot */
1436 dev = pci_scan_single_device(bus, devfn);
1442 for (fn = next_fn(bus, dev, 0); fn > 0; fn = next_fn(bus, dev, fn)) {
1443 dev = pci_scan_single_device(bus, devfn + fn);
1447 dev->multifunction = 1;
1451 /* only one slot has pcie device */
1452 if (bus->self && nr)
1453 pcie_aspm_init_link_state(bus->self);
1458 static int pcie_find_smpss(struct pci_dev *dev, void *data)
1462 if (!pci_is_pcie(dev))
1465 /* For PCIE hotplug enabled slots not connected directly to a
1466 * PCI-E root port, there can be problems when hotplugging
1467 * devices. This is due to the possibility of hotplugging a
1468 * device into the fabric with a smaller MPS that the devices
1469 * currently running have configured. Modifying the MPS on the
1470 * running devices could cause a fatal bus error due to an
1471 * incoming frame being larger than the newly configured MPS.
1472 * To work around this, the MPS for the entire fabric must be
1473 * set to the minimum size. Any devices hotplugged into this
1474 * fabric will have the minimum MPS set. If the PCI hotplug
1475 * slot is directly connected to the root port and there are not
1476 * other devices on the fabric (which seems to be the most
1477 * common case), then this is not an issue and MPS discovery
1478 * will occur as normal.
1480 if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) ||
1482 pci_pcie_type(dev->bus->self) != PCI_EXP_TYPE_ROOT_PORT)))
1485 if (*smpss > dev->pcie_mpss)
1486 *smpss = dev->pcie_mpss;
1491 static void pcie_write_mps(struct pci_dev *dev, int mps)
1495 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
1496 mps = 128 << dev->pcie_mpss;
1498 if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
1500 /* For "Performance", the assumption is made that
1501 * downstream communication will never be larger than
1502 * the MRRS. So, the MPS only needs to be configured
1503 * for the upstream communication. This being the case,
1504 * walk from the top down and set the MPS of the child
1505 * to that of the parent bus.
1507 * Configure the device MPS with the smaller of the
1508 * device MPSS or the bridge MPS (which is assumed to be
1509 * properly configured at this point to the largest
1510 * allowable MPS based on its parent bus).
1512 mps = min(mps, pcie_get_mps(dev->bus->self));
1515 rc = pcie_set_mps(dev, mps);
1517 dev_err(&dev->dev, "Failed attempting to set the MPS\n");
1520 static void pcie_write_mrrs(struct pci_dev *dev)
1524 /* In the "safe" case, do not configure the MRRS. There appear to be
1525 * issues with setting MRRS to 0 on a number of devices.
1527 if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
1530 /* For Max performance, the MRRS must be set to the largest supported
1531 * value. However, it cannot be configured larger than the MPS the
1532 * device or the bus can support. This should already be properly
1533 * configured by a prior call to pcie_write_mps.
1535 mrrs = pcie_get_mps(dev);
1537 /* MRRS is a R/W register. Invalid values can be written, but a
1538 * subsequent read will verify if the value is acceptable or not.
1539 * If the MRRS value provided is not acceptable (e.g., too large),
1540 * shrink the value until it is acceptable to the HW.
1542 while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
1543 rc = pcie_set_readrq(dev, mrrs);
1547 dev_warn(&dev->dev, "Failed attempting to set the MRRS\n");
1552 dev_err(&dev->dev, "MRRS was unable to be configured with a "
1553 "safe value. If problems are experienced, try running "
1554 "with pci=pcie_bus_safe.\n");
1557 static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
1561 if (!pci_is_pcie(dev))
1564 mps = 128 << *(u8 *)data;
1565 orig_mps = pcie_get_mps(dev);
1567 pcie_write_mps(dev, mps);
1568 pcie_write_mrrs(dev);
1570 dev_info(&dev->dev, "PCI-E Max Payload Size set to %4d/%4d (was %4d), "
1571 "Max Read Rq %4d\n", pcie_get_mps(dev), 128 << dev->pcie_mpss,
1572 orig_mps, pcie_get_readrq(dev));
1577 /* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down,
1578 * parents then children fashion. If this changes, then this code will not
1581 void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss)
1585 if (!pci_is_pcie(bus->self))
1588 if (pcie_bus_config == PCIE_BUS_TUNE_OFF)
1591 /* FIXME - Peer to peer DMA is possible, though the endpoint would need
1592 * to be aware to the MPS of the destination. To work around this,
1593 * simply force the MPS of the entire system to the smallest possible.
1595 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
1598 if (pcie_bus_config == PCIE_BUS_SAFE) {
1601 pcie_find_smpss(bus->self, &smpss);
1602 pci_walk_bus(bus, pcie_find_smpss, &smpss);
1605 pcie_bus_configure_set(bus->self, &smpss);
1606 pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
1608 EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
1610 unsigned int pci_scan_child_bus(struct pci_bus *bus)
1612 unsigned int devfn, pass, max = bus->busn_res.start;
1613 struct pci_dev *dev;
1615 dev_dbg(&bus->dev, "scanning bus\n");
1617 /* Go find them, Rover! */
1618 for (devfn = 0; devfn < 0x100; devfn += 8)
1619 pci_scan_slot(bus, devfn);
1621 /* Reserve buses for SR-IOV capability. */
1622 max += pci_iov_bus_range(bus);
1625 * After performing arch-dependent fixup of the bus, look behind
1626 * all PCI-to-PCI bridges on this bus.
1628 if (!bus->is_added) {
1629 dev_dbg(&bus->dev, "fixups for bus\n");
1630 pcibios_fixup_bus(bus);
1634 for (pass=0; pass < 2; pass++)
1635 list_for_each_entry(dev, &bus->devices, bus_list) {
1636 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
1637 dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
1638 max = pci_scan_bridge(bus, dev, max, pass);
1642 * We've scanned the bus and so we know all about what's on
1643 * the other side of any bridges that may be on this bus plus
1646 * Return how far we've got finding sub-buses.
1648 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
1653 * pcibios_root_bridge_prepare - Platform-specific host bridge setup.
1654 * @bridge: Host bridge to set up.
1656 * Default empty implementation. Replace with an architecture-specific setup
1657 * routine, if necessary.
1659 int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
1664 void __weak pcibios_add_bus(struct pci_bus *bus)
1668 void __weak pcibios_remove_bus(struct pci_bus *bus)
1672 struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
1673 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1676 struct pci_host_bridge *bridge;
1677 struct pci_bus *b, *b2;
1678 struct pci_host_bridge_window *window, *n;
1679 struct resource *res;
1680 resource_size_t offset;
1684 b = pci_alloc_bus();
1688 b->sysdata = sysdata;
1690 b->number = b->busn_res.start = bus;
1691 b2 = pci_find_bus(pci_domain_nr(b), bus);
1693 /* If we already got to this bus through a different bridge, ignore it */
1694 dev_dbg(&b2->dev, "bus already known\n");
1698 bridge = pci_alloc_host_bridge(b);
1702 bridge->dev.parent = parent;
1703 bridge->dev.release = pci_release_bus_bridge_dev;
1704 dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
1705 error = pcibios_root_bridge_prepare(bridge);
1707 goto bridge_dev_reg_err;
1709 error = device_register(&bridge->dev);
1711 goto bridge_dev_reg_err;
1712 b->bridge = get_device(&bridge->dev);
1713 device_enable_async_suspend(b->bridge);
1714 pci_set_bus_of_node(b);
1717 set_dev_node(b->bridge, pcibus_to_node(b));
1719 b->dev.class = &pcibus_class;
1720 b->dev.parent = b->bridge;
1721 dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
1722 error = device_register(&b->dev);
1724 goto class_dev_reg_err;
1728 /* Create legacy_io and legacy_mem files for this bus */
1729 pci_create_legacy_files(b);
1732 dev_info(parent, "PCI host bridge to bus %s\n", dev_name(&b->dev));
1734 printk(KERN_INFO "PCI host bridge to bus %s\n", dev_name(&b->dev));
1736 /* Add initial resources to the bus */
1737 list_for_each_entry_safe(window, n, resources, list) {
1738 list_move_tail(&window->list, &bridge->windows);
1740 offset = window->offset;
1741 if (res->flags & IORESOURCE_BUS)
1742 pci_bus_insert_busn_res(b, bus, res->end);
1744 pci_bus_add_resource(b, res, 0);
1746 if (resource_type(res) == IORESOURCE_IO)
1747 fmt = " (bus address [%#06llx-%#06llx])";
1749 fmt = " (bus address [%#010llx-%#010llx])";
1750 snprintf(bus_addr, sizeof(bus_addr), fmt,
1751 (unsigned long long) (res->start - offset),
1752 (unsigned long long) (res->end - offset));
1755 dev_info(&b->dev, "root bus resource %pR%s\n", res, bus_addr);
1758 down_write(&pci_bus_sem);
1759 list_add_tail(&b->node, &pci_root_buses);
1760 up_write(&pci_bus_sem);
1765 put_device(&bridge->dev);
1766 device_unregister(&bridge->dev);
1774 int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
1776 struct resource *res = &b->busn_res;
1777 struct resource *parent_res, *conflict;
1781 res->flags = IORESOURCE_BUS;
1783 if (!pci_is_root_bus(b))
1784 parent_res = &b->parent->busn_res;
1786 parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
1787 res->flags |= IORESOURCE_PCI_FIXED;
1790 conflict = insert_resource_conflict(parent_res, res);
1793 dev_printk(KERN_DEBUG, &b->dev,
1794 "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
1795 res, pci_is_root_bus(b) ? "domain " : "",
1796 parent_res, conflict->name, conflict);
1798 return conflict == NULL;
1801 int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
1803 struct resource *res = &b->busn_res;
1804 struct resource old_res = *res;
1805 resource_size_t size;
1808 if (res->start > bus_max)
1811 size = bus_max - res->start + 1;
1812 ret = adjust_resource(res, res->start, size);
1813 dev_printk(KERN_DEBUG, &b->dev,
1814 "busn_res: %pR end %s updated to %02x\n",
1815 &old_res, ret ? "can not be" : "is", bus_max);
1817 if (!ret && !res->parent)
1818 pci_bus_insert_busn_res(b, res->start, res->end);
1823 void pci_bus_release_busn_res(struct pci_bus *b)
1825 struct resource *res = &b->busn_res;
1828 if (!res->flags || !res->parent)
1831 ret = release_resource(res);
1832 dev_printk(KERN_DEBUG, &b->dev,
1833 "busn_res: %pR %s released\n",
1834 res, ret ? "can not be" : "is");
1837 struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
1838 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1840 struct pci_host_bridge_window *window;
1845 list_for_each_entry(window, resources, list)
1846 if (window->res->flags & IORESOURCE_BUS) {
1851 b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
1857 "No busn resource found for root bus, will use [bus %02x-ff]\n",
1859 pci_bus_insert_busn_res(b, bus, 255);
1862 max = pci_scan_child_bus(b);
1865 pci_bus_update_busn_res_end(b, max);
1867 pci_bus_add_devices(b);
1870 EXPORT_SYMBOL(pci_scan_root_bus);
1872 /* Deprecated; use pci_scan_root_bus() instead */
1873 struct pci_bus *pci_scan_bus_parented(struct device *parent,
1874 int bus, struct pci_ops *ops, void *sysdata)
1876 LIST_HEAD(resources);
1879 pci_add_resource(&resources, &ioport_resource);
1880 pci_add_resource(&resources, &iomem_resource);
1881 pci_add_resource(&resources, &busn_resource);
1882 b = pci_create_root_bus(parent, bus, ops, sysdata, &resources);
1884 pci_scan_child_bus(b);
1886 pci_free_resource_list(&resources);
1889 EXPORT_SYMBOL(pci_scan_bus_parented);
1891 struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
1894 LIST_HEAD(resources);
1897 pci_add_resource(&resources, &ioport_resource);
1898 pci_add_resource(&resources, &iomem_resource);
1899 pci_add_resource(&resources, &busn_resource);
1900 b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
1902 pci_scan_child_bus(b);
1903 pci_bus_add_devices(b);
1905 pci_free_resource_list(&resources);
1909 EXPORT_SYMBOL(pci_scan_bus);
1912 * pci_rescan_bus_bridge_resize - scan a PCI bus for devices.
1913 * @bridge: PCI bridge for the bus to scan
1915 * Scan a PCI bus and child buses for new devices, add them,
1916 * and enable them, resizing bridge mmio/io resource if necessary
1917 * and possible. The caller must ensure the child devices are already
1918 * removed for resizing to occur.
1920 * Returns the max number of subordinate bus discovered.
1922 unsigned int __ref pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
1925 struct pci_bus *bus = bridge->subordinate;
1927 max = pci_scan_child_bus(bus);
1929 pci_assign_unassigned_bridge_resources(bridge);
1931 pci_bus_add_devices(bus);
1937 * pci_rescan_bus - scan a PCI bus for devices.
1938 * @bus: PCI bus to scan
1940 * Scan a PCI bus and child buses for new devices, adds them,
1943 * Returns the max number of subordinate bus discovered.
1945 unsigned int __ref pci_rescan_bus(struct pci_bus *bus)
1949 max = pci_scan_child_bus(bus);
1950 pci_assign_unassigned_bus_resources(bus);
1951 pci_enable_bridges(bus);
1952 pci_bus_add_devices(bus);
1956 EXPORT_SYMBOL_GPL(pci_rescan_bus);
1958 EXPORT_SYMBOL(pci_add_new_bus);
1959 EXPORT_SYMBOL(pci_scan_slot);
1960 EXPORT_SYMBOL(pci_scan_bridge);
1961 EXPORT_SYMBOL_GPL(pci_scan_child_bus);
1963 static int __init pci_sort_bf_cmp(const struct device *d_a, const struct device *d_b)
1965 const struct pci_dev *a = to_pci_dev(d_a);
1966 const struct pci_dev *b = to_pci_dev(d_b);
1968 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
1969 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
1971 if (a->bus->number < b->bus->number) return -1;
1972 else if (a->bus->number > b->bus->number) return 1;
1974 if (a->devfn < b->devfn) return -1;
1975 else if (a->devfn > b->devfn) return 1;
1980 void __init pci_sort_breadthfirst(void)
1982 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);