2 * probe.c - PCI detection and setup code
5 #include <linux/kernel.h>
6 #include <linux/delay.h>
7 #include <linux/init.h>
9 #include <linux/slab.h>
10 #include <linux/module.h>
11 #include <linux/cpumask.h>
12 #include <linux/pci-aspm.h>
15 #define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
16 #define CARDBUS_RESERVE_BUSNR 3
18 /* Ugh. Need to stop exporting this to modules. */
19 LIST_HEAD(pci_root_buses
);
20 EXPORT_SYMBOL(pci_root_buses
);
23 static int find_anything(struct device
*dev
, void *data
)
29 * Some device drivers need know if pci is initiated.
30 * Basically, we think pci is not initiated when there
31 * is no device to be found on the pci_bus_type.
33 int no_pci_devices(void)
38 dev
= bus_find_device(&pci_bus_type
, NULL
, NULL
, find_anything
);
39 no_devices
= (dev
== NULL
);
43 EXPORT_SYMBOL(no_pci_devices
);
48 static void release_pcibus_dev(struct device
*dev
)
50 struct pci_bus
*pci_bus
= to_pci_bus(dev
);
53 put_device(pci_bus
->bridge
);
54 pci_bus_remove_resources(pci_bus
);
55 pci_release_bus_of_node(pci_bus
);
59 static struct class pcibus_class
= {
61 .dev_release
= &release_pcibus_dev
,
62 .dev_attrs
= pcibus_dev_attrs
,
65 static int __init
pcibus_class_init(void)
67 return class_register(&pcibus_class
);
69 postcore_initcall(pcibus_class_init
);
71 static u64
pci_size(u64 base
, u64 maxbase
, u64 mask
)
73 u64 size
= mask
& maxbase
; /* Find the significant bits */
77 /* Get the lowest of them to find the decode size, and
78 from that the extent. */
79 size
= (size
& ~(size
-1)) - 1;
81 /* base == maxbase can be valid only if the BAR has
82 already been programmed with all 1s. */
83 if (base
== maxbase
&& ((base
| size
) & mask
) != mask
)
89 static inline unsigned long decode_bar(struct pci_dev
*dev
, u32 bar
)
94 if ((bar
& PCI_BASE_ADDRESS_SPACE
) == PCI_BASE_ADDRESS_SPACE_IO
) {
95 flags
= bar
& ~PCI_BASE_ADDRESS_IO_MASK
;
96 flags
|= IORESOURCE_IO
;
100 flags
= bar
& ~PCI_BASE_ADDRESS_MEM_MASK
;
101 flags
|= IORESOURCE_MEM
;
102 if (flags
& PCI_BASE_ADDRESS_MEM_PREFETCH
)
103 flags
|= IORESOURCE_PREFETCH
;
105 mem_type
= bar
& PCI_BASE_ADDRESS_MEM_TYPE_MASK
;
107 case PCI_BASE_ADDRESS_MEM_TYPE_32
:
109 case PCI_BASE_ADDRESS_MEM_TYPE_1M
:
110 dev_info(&dev
->dev
, "1M mem BAR treated as 32-bit BAR\n");
112 case PCI_BASE_ADDRESS_MEM_TYPE_64
:
113 flags
|= IORESOURCE_MEM_64
;
117 "mem unknown type %x treated as 32-bit BAR\n",
125 * pci_read_base - read a PCI BAR
126 * @dev: the PCI device
127 * @type: type of the BAR
128 * @res: resource buffer to be filled in
129 * @pos: BAR position in the config space
131 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
133 int __pci_read_base(struct pci_dev
*dev
, enum pci_bar_type type
,
134 struct resource
*res
, unsigned int pos
)
139 mask
= type
? PCI_ROM_ADDRESS_MASK
: ~0;
141 if (!dev
->mmio_always_on
) {
142 pci_read_config_word(dev
, PCI_COMMAND
, &orig_cmd
);
143 pci_write_config_word(dev
, PCI_COMMAND
,
144 orig_cmd
& ~(PCI_COMMAND_MEMORY
| PCI_COMMAND_IO
));
147 res
->name
= pci_name(dev
);
149 pci_read_config_dword(dev
, pos
, &l
);
150 pci_write_config_dword(dev
, pos
, l
| mask
);
151 pci_read_config_dword(dev
, pos
, &sz
);
152 pci_write_config_dword(dev
, pos
, l
);
154 if (!dev
->mmio_always_on
)
155 pci_write_config_word(dev
, PCI_COMMAND
, orig_cmd
);
158 * All bits set in sz means the device isn't working properly.
159 * If the BAR isn't implemented, all bits must be 0. If it's a
160 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
163 if (!sz
|| sz
== 0xffffffff)
167 * I don't know how l can have all bits set. Copied from old code.
168 * Maybe it fixes a bug on some ancient platform.
173 if (type
== pci_bar_unknown
) {
174 res
->flags
= decode_bar(dev
, l
);
175 res
->flags
|= IORESOURCE_SIZEALIGN
;
176 if (res
->flags
& IORESOURCE_IO
) {
177 l
&= PCI_BASE_ADDRESS_IO_MASK
;
178 mask
= PCI_BASE_ADDRESS_IO_MASK
& (u32
) IO_SPACE_LIMIT
;
180 l
&= PCI_BASE_ADDRESS_MEM_MASK
;
181 mask
= (u32
)PCI_BASE_ADDRESS_MEM_MASK
;
184 res
->flags
|= (l
& IORESOURCE_ROM_ENABLE
);
185 l
&= PCI_ROM_ADDRESS_MASK
;
186 mask
= (u32
)PCI_ROM_ADDRESS_MASK
;
189 if (res
->flags
& IORESOURCE_MEM_64
) {
192 u64 mask64
= mask
| (u64
)~0 << 32;
194 pci_read_config_dword(dev
, pos
+ 4, &l
);
195 pci_write_config_dword(dev
, pos
+ 4, ~0);
196 pci_read_config_dword(dev
, pos
+ 4, &sz
);
197 pci_write_config_dword(dev
, pos
+ 4, l
);
199 l64
|= ((u64
)l
<< 32);
200 sz64
|= ((u64
)sz
<< 32);
202 sz64
= pci_size(l64
, sz64
, mask64
);
207 if ((sizeof(resource_size_t
) < 8) && (sz64
> 0x100000000ULL
)) {
208 dev_err(&dev
->dev
, "reg %x: can't handle 64-bit BAR\n",
213 if ((sizeof(resource_size_t
) < 8) && l
) {
214 /* Address above 32-bit boundary; disable the BAR */
215 pci_write_config_dword(dev
, pos
, 0);
216 pci_write_config_dword(dev
, pos
+ 4, 0);
221 res
->end
= l64
+ sz64
;
222 dev_printk(KERN_DEBUG
, &dev
->dev
, "reg %x: %pR\n",
226 sz
= pci_size(l
, sz
, mask
);
234 dev_printk(KERN_DEBUG
, &dev
->dev
, "reg %x: %pR\n", pos
, res
);
238 return (res
->flags
& IORESOURCE_MEM_64
) ? 1 : 0;
244 static void pci_read_bases(struct pci_dev
*dev
, unsigned int howmany
, int rom
)
246 unsigned int pos
, reg
;
248 for (pos
= 0; pos
< howmany
; pos
++) {
249 struct resource
*res
= &dev
->resource
[pos
];
250 reg
= PCI_BASE_ADDRESS_0
+ (pos
<< 2);
251 pos
+= __pci_read_base(dev
, pci_bar_unknown
, res
, reg
);
255 struct resource
*res
= &dev
->resource
[PCI_ROM_RESOURCE
];
256 dev
->rom_base_reg
= rom
;
257 res
->flags
= IORESOURCE_MEM
| IORESOURCE_PREFETCH
|
258 IORESOURCE_READONLY
| IORESOURCE_CACHEABLE
|
259 IORESOURCE_SIZEALIGN
;
260 __pci_read_base(dev
, pci_bar_mem32
, res
, rom
);
264 static void __devinit
pci_read_bridge_io(struct pci_bus
*child
)
266 struct pci_dev
*dev
= child
->self
;
267 u8 io_base_lo
, io_limit_lo
;
268 unsigned long base
, limit
;
269 struct resource
*res
;
271 res
= child
->resource
[0];
272 pci_read_config_byte(dev
, PCI_IO_BASE
, &io_base_lo
);
273 pci_read_config_byte(dev
, PCI_IO_LIMIT
, &io_limit_lo
);
274 base
= (io_base_lo
& PCI_IO_RANGE_MASK
) << 8;
275 limit
= (io_limit_lo
& PCI_IO_RANGE_MASK
) << 8;
277 if ((io_base_lo
& PCI_IO_RANGE_TYPE_MASK
) == PCI_IO_RANGE_TYPE_32
) {
278 u16 io_base_hi
, io_limit_hi
;
279 pci_read_config_word(dev
, PCI_IO_BASE_UPPER16
, &io_base_hi
);
280 pci_read_config_word(dev
, PCI_IO_LIMIT_UPPER16
, &io_limit_hi
);
281 base
|= (io_base_hi
<< 16);
282 limit
|= (io_limit_hi
<< 16);
285 if (base
&& base
<= limit
) {
286 res
->flags
= (io_base_lo
& PCI_IO_RANGE_TYPE_MASK
) | IORESOURCE_IO
;
290 res
->end
= limit
+ 0xfff;
291 dev_printk(KERN_DEBUG
, &dev
->dev
, " bridge window %pR\n", res
);
295 static void __devinit
pci_read_bridge_mmio(struct pci_bus
*child
)
297 struct pci_dev
*dev
= child
->self
;
298 u16 mem_base_lo
, mem_limit_lo
;
299 unsigned long base
, limit
;
300 struct resource
*res
;
302 res
= child
->resource
[1];
303 pci_read_config_word(dev
, PCI_MEMORY_BASE
, &mem_base_lo
);
304 pci_read_config_word(dev
, PCI_MEMORY_LIMIT
, &mem_limit_lo
);
305 base
= (mem_base_lo
& PCI_MEMORY_RANGE_MASK
) << 16;
306 limit
= (mem_limit_lo
& PCI_MEMORY_RANGE_MASK
) << 16;
307 if (base
&& base
<= limit
) {
308 res
->flags
= (mem_base_lo
& PCI_MEMORY_RANGE_TYPE_MASK
) | IORESOURCE_MEM
;
310 res
->end
= limit
+ 0xfffff;
311 dev_printk(KERN_DEBUG
, &dev
->dev
, " bridge window %pR\n", res
);
315 static void __devinit
pci_read_bridge_mmio_pref(struct pci_bus
*child
)
317 struct pci_dev
*dev
= child
->self
;
318 u16 mem_base_lo
, mem_limit_lo
;
319 unsigned long base
, limit
;
320 struct resource
*res
;
322 res
= child
->resource
[2];
323 pci_read_config_word(dev
, PCI_PREF_MEMORY_BASE
, &mem_base_lo
);
324 pci_read_config_word(dev
, PCI_PREF_MEMORY_LIMIT
, &mem_limit_lo
);
325 base
= (mem_base_lo
& PCI_PREF_RANGE_MASK
) << 16;
326 limit
= (mem_limit_lo
& PCI_PREF_RANGE_MASK
) << 16;
328 if ((mem_base_lo
& PCI_PREF_RANGE_TYPE_MASK
) == PCI_PREF_RANGE_TYPE_64
) {
329 u32 mem_base_hi
, mem_limit_hi
;
330 pci_read_config_dword(dev
, PCI_PREF_BASE_UPPER32
, &mem_base_hi
);
331 pci_read_config_dword(dev
, PCI_PREF_LIMIT_UPPER32
, &mem_limit_hi
);
334 * Some bridges set the base > limit by default, and some
335 * (broken) BIOSes do not initialize them. If we find
336 * this, just assume they are not being used.
338 if (mem_base_hi
<= mem_limit_hi
) {
339 #if BITS_PER_LONG == 64
340 base
|= ((long) mem_base_hi
) << 32;
341 limit
|= ((long) mem_limit_hi
) << 32;
343 if (mem_base_hi
|| mem_limit_hi
) {
344 dev_err(&dev
->dev
, "can't handle 64-bit "
345 "address space for bridge\n");
351 if (base
&& base
<= limit
) {
352 res
->flags
= (mem_base_lo
& PCI_PREF_RANGE_TYPE_MASK
) |
353 IORESOURCE_MEM
| IORESOURCE_PREFETCH
;
354 if (res
->flags
& PCI_PREF_RANGE_TYPE_64
)
355 res
->flags
|= IORESOURCE_MEM_64
;
357 res
->end
= limit
+ 0xfffff;
358 dev_printk(KERN_DEBUG
, &dev
->dev
, " bridge window %pR\n", res
);
362 void __devinit
pci_read_bridge_bases(struct pci_bus
*child
)
364 struct pci_dev
*dev
= child
->self
;
365 struct resource
*res
;
368 if (pci_is_root_bus(child
)) /* It's a host bus, nothing to read */
371 dev_info(&dev
->dev
, "PCI bridge to [bus %02x-%02x]%s\n",
372 child
->secondary
, child
->subordinate
,
373 dev
->transparent
? " (subtractive decode)" : "");
375 pci_bus_remove_resources(child
);
376 for (i
= 0; i
< PCI_BRIDGE_RESOURCE_NUM
; i
++)
377 child
->resource
[i
] = &dev
->resource
[PCI_BRIDGE_RESOURCES
+i
];
379 pci_read_bridge_io(child
);
380 pci_read_bridge_mmio(child
);
381 pci_read_bridge_mmio_pref(child
);
383 if (dev
->transparent
) {
384 pci_bus_for_each_resource(child
->parent
, res
, i
) {
386 pci_bus_add_resource(child
, res
,
387 PCI_SUBTRACTIVE_DECODE
);
388 dev_printk(KERN_DEBUG
, &dev
->dev
,
389 " bridge window %pR (subtractive decode)\n",
396 static struct pci_bus
* pci_alloc_bus(void)
400 b
= kzalloc(sizeof(*b
), GFP_KERNEL
);
402 INIT_LIST_HEAD(&b
->node
);
403 INIT_LIST_HEAD(&b
->children
);
404 INIT_LIST_HEAD(&b
->devices
);
405 INIT_LIST_HEAD(&b
->slots
);
406 INIT_LIST_HEAD(&b
->resources
);
407 b
->max_bus_speed
= PCI_SPEED_UNKNOWN
;
408 b
->cur_bus_speed
= PCI_SPEED_UNKNOWN
;
413 static unsigned char pcix_bus_speed
[] = {
414 PCI_SPEED_UNKNOWN
, /* 0 */
415 PCI_SPEED_66MHz_PCIX
, /* 1 */
416 PCI_SPEED_100MHz_PCIX
, /* 2 */
417 PCI_SPEED_133MHz_PCIX
, /* 3 */
418 PCI_SPEED_UNKNOWN
, /* 4 */
419 PCI_SPEED_66MHz_PCIX_ECC
, /* 5 */
420 PCI_SPEED_100MHz_PCIX_ECC
, /* 6 */
421 PCI_SPEED_133MHz_PCIX_ECC
, /* 7 */
422 PCI_SPEED_UNKNOWN
, /* 8 */
423 PCI_SPEED_66MHz_PCIX_266
, /* 9 */
424 PCI_SPEED_100MHz_PCIX_266
, /* A */
425 PCI_SPEED_133MHz_PCIX_266
, /* B */
426 PCI_SPEED_UNKNOWN
, /* C */
427 PCI_SPEED_66MHz_PCIX_533
, /* D */
428 PCI_SPEED_100MHz_PCIX_533
, /* E */
429 PCI_SPEED_133MHz_PCIX_533
/* F */
432 static unsigned char pcie_link_speed
[] = {
433 PCI_SPEED_UNKNOWN
, /* 0 */
434 PCIE_SPEED_2_5GT
, /* 1 */
435 PCIE_SPEED_5_0GT
, /* 2 */
436 PCIE_SPEED_8_0GT
, /* 3 */
437 PCI_SPEED_UNKNOWN
, /* 4 */
438 PCI_SPEED_UNKNOWN
, /* 5 */
439 PCI_SPEED_UNKNOWN
, /* 6 */
440 PCI_SPEED_UNKNOWN
, /* 7 */
441 PCI_SPEED_UNKNOWN
, /* 8 */
442 PCI_SPEED_UNKNOWN
, /* 9 */
443 PCI_SPEED_UNKNOWN
, /* A */
444 PCI_SPEED_UNKNOWN
, /* B */
445 PCI_SPEED_UNKNOWN
, /* C */
446 PCI_SPEED_UNKNOWN
, /* D */
447 PCI_SPEED_UNKNOWN
, /* E */
448 PCI_SPEED_UNKNOWN
/* F */
451 void pcie_update_link_speed(struct pci_bus
*bus
, u16 linksta
)
453 bus
->cur_bus_speed
= pcie_link_speed
[linksta
& 0xf];
455 EXPORT_SYMBOL_GPL(pcie_update_link_speed
);
457 static unsigned char agp_speeds
[] = {
465 static enum pci_bus_speed
agp_speed(int agp3
, int agpstat
)
471 else if (agpstat
& 2)
473 else if (agpstat
& 1)
485 return agp_speeds
[index
];
489 static void pci_set_bus_speed(struct pci_bus
*bus
)
491 struct pci_dev
*bridge
= bus
->self
;
494 pos
= pci_find_capability(bridge
, PCI_CAP_ID_AGP
);
496 pos
= pci_find_capability(bridge
, PCI_CAP_ID_AGP3
);
500 pci_read_config_dword(bridge
, pos
+ PCI_AGP_STATUS
, &agpstat
);
501 bus
->max_bus_speed
= agp_speed(agpstat
& 8, agpstat
& 7);
503 pci_read_config_dword(bridge
, pos
+ PCI_AGP_COMMAND
, &agpcmd
);
504 bus
->cur_bus_speed
= agp_speed(agpstat
& 8, agpcmd
& 7);
507 pos
= pci_find_capability(bridge
, PCI_CAP_ID_PCIX
);
510 enum pci_bus_speed max
;
511 pci_read_config_word(bridge
, pos
+ 2, &status
);
513 if (status
& 0x8000) {
514 max
= PCI_SPEED_133MHz_PCIX_533
;
515 } else if (status
& 0x4000) {
516 max
= PCI_SPEED_133MHz_PCIX_266
;
517 } else if (status
& 0x0002) {
518 if (((status
>> 12) & 0x3) == 2) {
519 max
= PCI_SPEED_133MHz_PCIX_ECC
;
521 max
= PCI_SPEED_133MHz_PCIX
;
524 max
= PCI_SPEED_66MHz_PCIX
;
527 bus
->max_bus_speed
= max
;
528 bus
->cur_bus_speed
= pcix_bus_speed
[(status
>> 6) & 0xf];
533 pos
= pci_find_capability(bridge
, PCI_CAP_ID_EXP
);
538 pci_read_config_dword(bridge
, pos
+ PCI_EXP_LNKCAP
, &linkcap
);
539 bus
->max_bus_speed
= pcie_link_speed
[linkcap
& 0xf];
541 pci_read_config_word(bridge
, pos
+ PCI_EXP_LNKSTA
, &linksta
);
542 pcie_update_link_speed(bus
, linksta
);
547 static struct pci_bus
*pci_alloc_child_bus(struct pci_bus
*parent
,
548 struct pci_dev
*bridge
, int busnr
)
550 struct pci_bus
*child
;
554 * Allocate a new bus, and inherit stuff from the parent..
556 child
= pci_alloc_bus();
560 child
->parent
= parent
;
561 child
->ops
= parent
->ops
;
562 child
->sysdata
= parent
->sysdata
;
563 child
->bus_flags
= parent
->bus_flags
;
565 /* initialize some portions of the bus device, but don't register it
566 * now as the parent is not properly set up yet. This device will get
567 * registered later in pci_bus_add_devices()
569 child
->dev
.class = &pcibus_class
;
570 dev_set_name(&child
->dev
, "%04x:%02x", pci_domain_nr(child
), busnr
);
573 * Set up the primary, secondary and subordinate
576 child
->number
= child
->secondary
= busnr
;
577 child
->primary
= parent
->secondary
;
578 child
->subordinate
= 0xff;
583 child
->self
= bridge
;
584 child
->bridge
= get_device(&bridge
->dev
);
585 pci_set_bus_of_node(child
);
586 pci_set_bus_speed(child
);
588 /* Set up default resource pointers and names.. */
589 for (i
= 0; i
< PCI_BRIDGE_RESOURCE_NUM
; i
++) {
590 child
->resource
[i
] = &bridge
->resource
[PCI_BRIDGE_RESOURCES
+i
];
591 child
->resource
[i
]->name
= child
->name
;
593 bridge
->subordinate
= child
;
598 struct pci_bus
*__ref
pci_add_new_bus(struct pci_bus
*parent
, struct pci_dev
*dev
, int busnr
)
600 struct pci_bus
*child
;
602 child
= pci_alloc_child_bus(parent
, dev
, busnr
);
604 down_write(&pci_bus_sem
);
605 list_add_tail(&child
->node
, &parent
->children
);
606 up_write(&pci_bus_sem
);
611 static void pci_fixup_parent_subordinate_busnr(struct pci_bus
*child
, int max
)
613 struct pci_bus
*parent
= child
->parent
;
615 /* Attempts to fix that up are really dangerous unless
616 we're going to re-assign all bus numbers. */
617 if (!pcibios_assign_all_busses())
620 while (parent
->parent
&& parent
->subordinate
< max
) {
621 parent
->subordinate
= max
;
622 pci_write_config_byte(parent
->self
, PCI_SUBORDINATE_BUS
, max
);
623 parent
= parent
->parent
;
628 * If it's a bridge, configure it and scan the bus behind it.
629 * For CardBus bridges, we don't scan behind as the devices will
630 * be handled by the bridge driver itself.
632 * We need to process bridges in two passes -- first we scan those
633 * already configured by the BIOS and after we are done with all of
634 * them, we proceed to assigning numbers to the remaining buses in
635 * order to avoid overlaps between old and new bus numbers.
637 int __devinit
pci_scan_bridge(struct pci_bus
*bus
, struct pci_dev
*dev
, int max
, int pass
)
639 struct pci_bus
*child
;
640 int is_cardbus
= (dev
->hdr_type
== PCI_HEADER_TYPE_CARDBUS
);
643 u8 primary
, secondary
, subordinate
;
646 pci_read_config_dword(dev
, PCI_PRIMARY_BUS
, &buses
);
647 primary
= buses
& 0xFF;
648 secondary
= (buses
>> 8) & 0xFF;
649 subordinate
= (buses
>> 16) & 0xFF;
651 dev_dbg(&dev
->dev
, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
652 secondary
, subordinate
, pass
);
654 /* Check if setup is sensible at all */
656 (primary
!= bus
->number
|| secondary
<= bus
->number
)) {
657 dev_dbg(&dev
->dev
, "bus configuration invalid, reconfiguring\n");
661 /* Disable MasterAbortMode during probing to avoid reporting
662 of bus errors (in some architectures) */
663 pci_read_config_word(dev
, PCI_BRIDGE_CONTROL
, &bctl
);
664 pci_write_config_word(dev
, PCI_BRIDGE_CONTROL
,
665 bctl
& ~PCI_BRIDGE_CTL_MASTER_ABORT
);
667 if ((secondary
|| subordinate
) && !pcibios_assign_all_busses() &&
668 !is_cardbus
&& !broken
) {
671 * Bus already configured by firmware, process it in the first
672 * pass and just note the configuration.
678 * If we already got to this bus through a different bridge,
679 * don't re-add it. This can happen with the i450NX chipset.
681 * However, we continue to descend down the hierarchy and
682 * scan remaining child buses.
684 child
= pci_find_bus(pci_domain_nr(bus
), secondary
);
686 child
= pci_add_new_bus(bus
, dev
, secondary
);
689 child
->primary
= primary
;
690 child
->subordinate
= subordinate
;
691 child
->bridge_ctl
= bctl
;
694 cmax
= pci_scan_child_bus(child
);
697 if (child
->subordinate
> max
)
698 max
= child
->subordinate
;
701 * We need to assign a number to this bus which we always
702 * do in the second pass.
705 if (pcibios_assign_all_busses() || broken
)
706 /* Temporarily disable forwarding of the
707 configuration cycles on all bridges in
708 this bus segment to avoid possible
709 conflicts in the second pass between two
710 bridges programmed with overlapping
712 pci_write_config_dword(dev
, PCI_PRIMARY_BUS
,
718 pci_write_config_word(dev
, PCI_STATUS
, 0xffff);
721 * Prevent assigning a bus number that already exists. This can
722 * happen when a bridge is hot-plugged, so in this case we only
725 child
= pci_find_bus(pci_domain_nr(bus
), max
+1);
727 child
= pci_add_new_bus(bus
, dev
, ++max
);
731 buses
= (buses
& 0xff000000)
732 | ((unsigned int)(child
->primary
) << 0)
733 | ((unsigned int)(child
->secondary
) << 8)
734 | ((unsigned int)(child
->subordinate
) << 16);
737 * yenta.c forces a secondary latency timer of 176.
738 * Copy that behaviour here.
741 buses
&= ~0xff000000;
742 buses
|= CARDBUS_LATENCY_TIMER
<< 24;
746 * We need to blast all three values with a single write.
748 pci_write_config_dword(dev
, PCI_PRIMARY_BUS
, buses
);
751 child
->bridge_ctl
= bctl
;
753 * Adjust subordinate busnr in parent buses.
754 * We do this before scanning for children because
755 * some devices may not be detected if the bios
758 pci_fixup_parent_subordinate_busnr(child
, max
);
759 /* Now we can scan all subordinate buses... */
760 max
= pci_scan_child_bus(child
);
762 * now fix it up again since we have found
763 * the real value of max.
765 pci_fixup_parent_subordinate_busnr(child
, max
);
768 * For CardBus bridges, we leave 4 bus numbers
769 * as cards with a PCI-to-PCI bridge can be
772 for (i
=0; i
<CARDBUS_RESERVE_BUSNR
; i
++) {
773 struct pci_bus
*parent
= bus
;
774 if (pci_find_bus(pci_domain_nr(bus
),
777 while (parent
->parent
) {
778 if ((!pcibios_assign_all_busses()) &&
779 (parent
->subordinate
> max
) &&
780 (parent
->subordinate
<= max
+i
)) {
783 parent
= parent
->parent
;
787 * Often, there are two cardbus bridges
788 * -- try to leave one valid bus number
796 pci_fixup_parent_subordinate_busnr(child
, max
);
799 * Set the subordinate bus number to its real value.
801 child
->subordinate
= max
;
802 pci_write_config_byte(dev
, PCI_SUBORDINATE_BUS
, max
);
806 (is_cardbus
? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
807 pci_domain_nr(bus
), child
->number
);
809 /* Has only triggered on CardBus, fixup is in yenta_socket */
810 while (bus
->parent
) {
811 if ((child
->subordinate
> bus
->subordinate
) ||
812 (child
->number
> bus
->subordinate
) ||
813 (child
->number
< bus
->number
) ||
814 (child
->subordinate
< bus
->number
)) {
815 dev_info(&child
->dev
, "[bus %02x-%02x] %s "
816 "hidden behind%s bridge %s [bus %02x-%02x]\n",
817 child
->number
, child
->subordinate
,
818 (bus
->number
> child
->subordinate
&&
819 bus
->subordinate
< child
->number
) ?
820 "wholly" : "partially",
821 bus
->self
->transparent
? " transparent" : "",
823 bus
->number
, bus
->subordinate
);
829 pci_write_config_word(dev
, PCI_BRIDGE_CONTROL
, bctl
);
835 * Read interrupt line and base address registers.
836 * The architecture-dependent code can tweak these, of course.
838 static void pci_read_irq(struct pci_dev
*dev
)
842 pci_read_config_byte(dev
, PCI_INTERRUPT_PIN
, &irq
);
845 pci_read_config_byte(dev
, PCI_INTERRUPT_LINE
, &irq
);
849 void set_pcie_port_type(struct pci_dev
*pdev
)
854 pos
= pci_find_capability(pdev
, PCI_CAP_ID_EXP
);
858 pdev
->pcie_cap
= pos
;
859 pci_read_config_word(pdev
, pos
+ PCI_EXP_FLAGS
, ®16
);
860 pdev
->pcie_type
= (reg16
& PCI_EXP_FLAGS_TYPE
) >> 4;
863 void set_pcie_hotplug_bridge(struct pci_dev
*pdev
)
869 pos
= pci_pcie_cap(pdev
);
872 pci_read_config_word(pdev
, pos
+ PCI_EXP_FLAGS
, ®16
);
873 if (!(reg16
& PCI_EXP_FLAGS_SLOT
))
875 pci_read_config_dword(pdev
, pos
+ PCI_EXP_SLTCAP
, ®32
);
876 if (reg32
& PCI_EXP_SLTCAP_HPC
)
877 pdev
->is_hotplug_bridge
= 1;
880 #define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
883 * pci_setup_device - fill in class and map information of a device
884 * @dev: the device structure to fill
886 * Initialize the device structure with information about the device's
887 * vendor,class,memory and IO-space addresses,IRQ lines etc.
888 * Called at initialisation of the PCI subsystem and by CardBus services.
889 * Returns 0 on success and negative if unknown type of device (not normal,
890 * bridge or CardBus).
892 int pci_setup_device(struct pci_dev
*dev
)
896 struct pci_slot
*slot
;
899 if (pci_read_config_byte(dev
, PCI_HEADER_TYPE
, &hdr_type
))
902 dev
->sysdata
= dev
->bus
->sysdata
;
903 dev
->dev
.parent
= dev
->bus
->bridge
;
904 dev
->dev
.bus
= &pci_bus_type
;
905 dev
->hdr_type
= hdr_type
& 0x7f;
906 dev
->multifunction
= !!(hdr_type
& 0x80);
907 dev
->error_state
= pci_channel_io_normal
;
908 set_pcie_port_type(dev
);
910 list_for_each_entry(slot
, &dev
->bus
->slots
, list
)
911 if (PCI_SLOT(dev
->devfn
) == slot
->number
)
914 /* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
915 set this higher, assuming the system even supports it. */
916 dev
->dma_mask
= 0xffffffff;
918 dev_set_name(&dev
->dev
, "%04x:%02x:%02x.%d", pci_domain_nr(dev
->bus
),
919 dev
->bus
->number
, PCI_SLOT(dev
->devfn
),
920 PCI_FUNC(dev
->devfn
));
922 pci_read_config_dword(dev
, PCI_CLASS_REVISION
, &class);
923 dev
->revision
= class & 0xff;
924 class >>= 8; /* upper 3 bytes */
928 dev_printk(KERN_DEBUG
, &dev
->dev
, "[%04x:%04x] type %d class %#08x\n",
929 dev
->vendor
, dev
->device
, dev
->hdr_type
, class);
931 /* need to have dev->class ready */
932 dev
->cfg_size
= pci_cfg_space_size(dev
);
934 /* "Unknown power state" */
935 dev
->current_state
= PCI_UNKNOWN
;
937 /* Early fixups, before probing the BARs */
938 pci_fixup_device(pci_fixup_early
, dev
);
939 /* device class may be changed after fixup */
940 class = dev
->class >> 8;
942 switch (dev
->hdr_type
) { /* header type */
943 case PCI_HEADER_TYPE_NORMAL
: /* standard header */
944 if (class == PCI_CLASS_BRIDGE_PCI
)
947 pci_read_bases(dev
, 6, PCI_ROM_ADDRESS
);
948 pci_read_config_word(dev
, PCI_SUBSYSTEM_VENDOR_ID
, &dev
->subsystem_vendor
);
949 pci_read_config_word(dev
, PCI_SUBSYSTEM_ID
, &dev
->subsystem_device
);
952 * Do the ugly legacy mode stuff here rather than broken chip
953 * quirk code. Legacy mode ATA controllers have fixed
954 * addresses. These are not always echoed in BAR0-3, and
955 * BAR0-3 in a few cases contain junk!
957 if (class == PCI_CLASS_STORAGE_IDE
) {
959 pci_read_config_byte(dev
, PCI_CLASS_PROG
, &progif
);
960 if ((progif
& 1) == 0) {
961 dev
->resource
[0].start
= 0x1F0;
962 dev
->resource
[0].end
= 0x1F7;
963 dev
->resource
[0].flags
= LEGACY_IO_RESOURCE
;
964 dev
->resource
[1].start
= 0x3F6;
965 dev
->resource
[1].end
= 0x3F6;
966 dev
->resource
[1].flags
= LEGACY_IO_RESOURCE
;
968 if ((progif
& 4) == 0) {
969 dev
->resource
[2].start
= 0x170;
970 dev
->resource
[2].end
= 0x177;
971 dev
->resource
[2].flags
= LEGACY_IO_RESOURCE
;
972 dev
->resource
[3].start
= 0x376;
973 dev
->resource
[3].end
= 0x376;
974 dev
->resource
[3].flags
= LEGACY_IO_RESOURCE
;
979 case PCI_HEADER_TYPE_BRIDGE
: /* bridge header */
980 if (class != PCI_CLASS_BRIDGE_PCI
)
982 /* The PCI-to-PCI bridge spec requires that subtractive
983 decoding (i.e. transparent) bridge must have programming
984 interface code of 0x01. */
986 dev
->transparent
= ((dev
->class & 0xff) == 1);
987 pci_read_bases(dev
, 2, PCI_ROM_ADDRESS1
);
988 set_pcie_hotplug_bridge(dev
);
989 pos
= pci_find_capability(dev
, PCI_CAP_ID_SSVID
);
991 pci_read_config_word(dev
, pos
+ PCI_SSVID_VENDOR_ID
, &dev
->subsystem_vendor
);
992 pci_read_config_word(dev
, pos
+ PCI_SSVID_DEVICE_ID
, &dev
->subsystem_device
);
996 case PCI_HEADER_TYPE_CARDBUS
: /* CardBus bridge header */
997 if (class != PCI_CLASS_BRIDGE_CARDBUS
)
1000 pci_read_bases(dev
, 1, 0);
1001 pci_read_config_word(dev
, PCI_CB_SUBSYSTEM_VENDOR_ID
, &dev
->subsystem_vendor
);
1002 pci_read_config_word(dev
, PCI_CB_SUBSYSTEM_ID
, &dev
->subsystem_device
);
1005 default: /* unknown header */
1006 dev_err(&dev
->dev
, "unknown header type %02x, "
1007 "ignoring device\n", dev
->hdr_type
);
1011 dev_err(&dev
->dev
, "ignoring class %02x (doesn't match header "
1012 "type %02x)\n", class, dev
->hdr_type
);
1013 dev
->class = PCI_CLASS_NOT_DEFINED
;
1016 /* We found a fine healthy device, go go go... */
1020 static void pci_release_capabilities(struct pci_dev
*dev
)
1022 pci_vpd_release(dev
);
1023 pci_iov_release(dev
);
1027 * pci_release_dev - free a pci device structure when all users of it are finished.
1028 * @dev: device that's been disconnected
1030 * Will be called only by the device core when all users of this pci device are
1033 static void pci_release_dev(struct device
*dev
)
1035 struct pci_dev
*pci_dev
;
1037 pci_dev
= to_pci_dev(dev
);
1038 pci_release_capabilities(pci_dev
);
1039 pci_release_of_node(pci_dev
);
1044 * pci_cfg_space_size - get the configuration space size of the PCI device.
1047 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1048 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1049 * access it. Maybe we don't have a way to generate extended config space
1050 * accesses, or the device is behind a reverse Express bridge. So we try
1051 * reading the dword at 0x100 which must either be 0 or a valid extended
1052 * capability header.
1054 int pci_cfg_space_size_ext(struct pci_dev
*dev
)
1057 int pos
= PCI_CFG_SPACE_SIZE
;
1059 if (pci_read_config_dword(dev
, pos
, &status
) != PCIBIOS_SUCCESSFUL
)
1061 if (status
== 0xffffffff)
1064 return PCI_CFG_SPACE_EXP_SIZE
;
1067 return PCI_CFG_SPACE_SIZE
;
1070 int pci_cfg_space_size(struct pci_dev
*dev
)
1076 class = dev
->class >> 8;
1077 if (class == PCI_CLASS_BRIDGE_HOST
)
1078 return pci_cfg_space_size_ext(dev
);
1080 pos
= pci_pcie_cap(dev
);
1082 pos
= pci_find_capability(dev
, PCI_CAP_ID_PCIX
);
1086 pci_read_config_dword(dev
, pos
+ PCI_X_STATUS
, &status
);
1087 if (!(status
& (PCI_X_STATUS_266MHZ
| PCI_X_STATUS_533MHZ
)))
1091 return pci_cfg_space_size_ext(dev
);
1094 return PCI_CFG_SPACE_SIZE
;
1097 static void pci_release_bus_bridge_dev(struct device
*dev
)
1102 struct pci_dev
*alloc_pci_dev(void)
1104 struct pci_dev
*dev
;
1106 dev
= kzalloc(sizeof(struct pci_dev
), GFP_KERNEL
);
1110 INIT_LIST_HEAD(&dev
->bus_list
);
1114 EXPORT_SYMBOL(alloc_pci_dev
);
1117 * Read the config data for a PCI device, sanity-check it
1118 * and fill in the dev structure...
1120 static struct pci_dev
*pci_scan_device(struct pci_bus
*bus
, int devfn
)
1122 struct pci_dev
*dev
;
1126 if (pci_bus_read_config_dword(bus
, devfn
, PCI_VENDOR_ID
, &l
))
1129 /* some broken boards return 0 or ~0 if a slot is empty: */
1130 if (l
== 0xffffffff || l
== 0x00000000 ||
1131 l
== 0x0000ffff || l
== 0xffff0000)
1134 /* Configuration request Retry Status */
1135 while (l
== 0xffff0001) {
1138 if (pci_bus_read_config_dword(bus
, devfn
, PCI_VENDOR_ID
, &l
))
1140 /* Card hasn't responded in 60 seconds? Must be stuck. */
1141 if (delay
> 60 * 1000) {
1142 printk(KERN_WARNING
"pci %04x:%02x:%02x.%d: not "
1143 "responding\n", pci_domain_nr(bus
),
1144 bus
->number
, PCI_SLOT(devfn
),
1150 dev
= alloc_pci_dev();
1156 dev
->vendor
= l
& 0xffff;
1157 dev
->device
= (l
>> 16) & 0xffff;
1159 pci_set_of_node(dev
);
1161 if (pci_setup_device(dev
)) {
1169 static void pci_init_capabilities(struct pci_dev
*dev
)
1171 /* MSI/MSI-X list */
1172 pci_msi_init_pci_dev(dev
);
1174 /* Buffers for saving PCIe and PCI-X capabilities */
1175 pci_allocate_cap_save_buffers(dev
);
1177 /* Power Management */
1179 platform_pci_wakeup_init(dev
);
1181 /* Vital Product Data */
1182 pci_vpd_pci22_init(dev
);
1184 /* Alternative Routing-ID Forwarding */
1185 pci_enable_ari(dev
);
1187 /* Single Root I/O Virtualization */
1190 /* Enable ACS P2P upstream forwarding */
1191 pci_enable_acs(dev
);
1194 void pci_device_add(struct pci_dev
*dev
, struct pci_bus
*bus
)
1196 device_initialize(&dev
->dev
);
1197 dev
->dev
.release
= pci_release_dev
;
1200 dev
->dev
.dma_mask
= &dev
->dma_mask
;
1201 dev
->dev
.dma_parms
= &dev
->dma_parms
;
1202 dev
->dev
.coherent_dma_mask
= 0xffffffffull
;
1204 pci_set_dma_max_seg_size(dev
, 65536);
1205 pci_set_dma_seg_boundary(dev
, 0xffffffff);
1207 /* Fix up broken headers */
1208 pci_fixup_device(pci_fixup_header
, dev
);
1210 /* Clear the state_saved flag. */
1211 dev
->state_saved
= false;
1213 /* Initialize various capabilities */
1214 pci_init_capabilities(dev
);
1217 * Add the device to our list of discovered devices
1218 * and the bus list for fixup functions, etc.
1220 down_write(&pci_bus_sem
);
1221 list_add_tail(&dev
->bus_list
, &bus
->devices
);
1222 up_write(&pci_bus_sem
);
1225 struct pci_dev
*__ref
pci_scan_single_device(struct pci_bus
*bus
, int devfn
)
1227 struct pci_dev
*dev
;
1229 dev
= pci_get_slot(bus
, devfn
);
1235 dev
= pci_scan_device(bus
, devfn
);
1239 pci_device_add(dev
, bus
);
1243 EXPORT_SYMBOL(pci_scan_single_device
);
1245 static unsigned next_ari_fn(struct pci_dev
*dev
, unsigned fn
)
1248 unsigned pos
, next_fn
;
1253 pos
= pci_find_ext_capability(dev
, PCI_EXT_CAP_ID_ARI
);
1256 pci_read_config_word(dev
, pos
+ 4, &cap
);
1263 static unsigned next_trad_fn(struct pci_dev
*dev
, unsigned fn
)
1265 return (fn
+ 1) % 8;
1268 static unsigned no_next_fn(struct pci_dev
*dev
, unsigned fn
)
1273 static int only_one_child(struct pci_bus
*bus
)
1275 struct pci_dev
*parent
= bus
->self
;
1276 if (!parent
|| !pci_is_pcie(parent
))
1278 if (parent
->pcie_type
== PCI_EXP_TYPE_ROOT_PORT
||
1279 parent
->pcie_type
== PCI_EXP_TYPE_DOWNSTREAM
)
1285 * pci_scan_slot - scan a PCI slot on a bus for devices.
1286 * @bus: PCI bus to scan
1287 * @devfn: slot number to scan (must have zero function.)
1289 * Scan a PCI slot on the specified PCI bus for devices, adding
1290 * discovered devices to the @bus->devices list. New devices
1291 * will not have is_added set.
1293 * Returns the number of new devices found.
1295 int pci_scan_slot(struct pci_bus
*bus
, int devfn
)
1297 unsigned fn
, nr
= 0;
1298 struct pci_dev
*dev
;
1299 unsigned (*next_fn
)(struct pci_dev
*, unsigned) = no_next_fn
;
1301 if (only_one_child(bus
) && (devfn
> 0))
1302 return 0; /* Already scanned the entire slot */
1304 dev
= pci_scan_single_device(bus
, devfn
);
1310 if (pci_ari_enabled(bus
))
1311 next_fn
= next_ari_fn
;
1312 else if (dev
->multifunction
)
1313 next_fn
= next_trad_fn
;
1315 for (fn
= next_fn(dev
, 0); fn
> 0; fn
= next_fn(dev
, fn
)) {
1316 dev
= pci_scan_single_device(bus
, devfn
+ fn
);
1320 dev
->multifunction
= 1;
1324 /* only one slot has pcie device */
1325 if (bus
->self
&& nr
)
1326 pcie_aspm_init_link_state(bus
->self
);
1331 unsigned int __devinit
pci_scan_child_bus(struct pci_bus
*bus
)
1333 unsigned int devfn
, pass
, max
= bus
->secondary
;
1334 struct pci_dev
*dev
;
1336 dev_dbg(&bus
->dev
, "scanning bus\n");
1338 /* Go find them, Rover! */
1339 for (devfn
= 0; devfn
< 0x100; devfn
+= 8)
1340 pci_scan_slot(bus
, devfn
);
1342 /* Reserve buses for SR-IOV capability. */
1343 max
+= pci_iov_bus_range(bus
);
1346 * After performing arch-dependent fixup of the bus, look behind
1347 * all PCI-to-PCI bridges on this bus.
1349 if (!bus
->is_added
) {
1350 dev_dbg(&bus
->dev
, "fixups for bus\n");
1351 pcibios_fixup_bus(bus
);
1352 if (pci_is_root_bus(bus
))
1356 for (pass
=0; pass
< 2; pass
++)
1357 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
1358 if (dev
->hdr_type
== PCI_HEADER_TYPE_BRIDGE
||
1359 dev
->hdr_type
== PCI_HEADER_TYPE_CARDBUS
)
1360 max
= pci_scan_bridge(bus
, dev
, max
, pass
);
1364 * We've scanned the bus and so we know all about what's on
1365 * the other side of any bridges that may be on this bus plus
1368 * Return how far we've got finding sub-buses.
1370 dev_dbg(&bus
->dev
, "bus scan returning with max=%02x\n", max
);
1374 struct pci_bus
* pci_create_bus(struct device
*parent
,
1375 int bus
, struct pci_ops
*ops
, void *sysdata
)
1378 struct pci_bus
*b
, *b2
;
1381 b
= pci_alloc_bus();
1385 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
1391 b
->sysdata
= sysdata
;
1394 b2
= pci_find_bus(pci_domain_nr(b
), bus
);
1396 /* If we already got to this bus through a different bridge, ignore it */
1397 dev_dbg(&b2
->dev
, "bus already known\n");
1401 down_write(&pci_bus_sem
);
1402 list_add_tail(&b
->node
, &pci_root_buses
);
1403 up_write(&pci_bus_sem
);
1405 dev
->parent
= parent
;
1406 dev
->release
= pci_release_bus_bridge_dev
;
1407 dev_set_name(dev
, "pci%04x:%02x", pci_domain_nr(b
), bus
);
1408 error
= device_register(dev
);
1411 b
->bridge
= get_device(dev
);
1412 device_enable_async_suspend(b
->bridge
);
1413 pci_set_bus_of_node(b
);
1416 set_dev_node(b
->bridge
, pcibus_to_node(b
));
1418 b
->dev
.class = &pcibus_class
;
1419 b
->dev
.parent
= b
->bridge
;
1420 dev_set_name(&b
->dev
, "%04x:%02x", pci_domain_nr(b
), bus
);
1421 error
= device_register(&b
->dev
);
1423 goto class_dev_reg_err
;
1425 /* Create legacy_io and legacy_mem files for this bus */
1426 pci_create_legacy_files(b
);
1428 b
->number
= b
->secondary
= bus
;
1429 b
->resource
[0] = &ioport_resource
;
1430 b
->resource
[1] = &iomem_resource
;
1435 device_unregister(dev
);
1437 down_write(&pci_bus_sem
);
1439 up_write(&pci_bus_sem
);
1446 struct pci_bus
* __devinit
pci_scan_bus_parented(struct device
*parent
,
1447 int bus
, struct pci_ops
*ops
, void *sysdata
)
1451 b
= pci_create_bus(parent
, bus
, ops
, sysdata
);
1453 b
->subordinate
= pci_scan_child_bus(b
);
1456 EXPORT_SYMBOL(pci_scan_bus_parented
);
1458 #ifdef CONFIG_HOTPLUG
1460 * pci_rescan_bus - scan a PCI bus for devices.
1461 * @bus: PCI bus to scan
1463 * Scan a PCI bus and child buses for new devices, adds them,
1466 * Returns the max number of subordinate bus discovered.
1468 unsigned int __ref
pci_rescan_bus(struct pci_bus
*bus
)
1471 struct pci_dev
*dev
;
1473 max
= pci_scan_child_bus(bus
);
1475 down_read(&pci_bus_sem
);
1476 list_for_each_entry(dev
, &bus
->devices
, bus_list
)
1477 if (dev
->hdr_type
== PCI_HEADER_TYPE_BRIDGE
||
1478 dev
->hdr_type
== PCI_HEADER_TYPE_CARDBUS
)
1479 if (dev
->subordinate
)
1480 pci_bus_size_bridges(dev
->subordinate
);
1481 up_read(&pci_bus_sem
);
1483 pci_bus_assign_resources(bus
);
1484 pci_enable_bridges(bus
);
1485 pci_bus_add_devices(bus
);
1489 EXPORT_SYMBOL_GPL(pci_rescan_bus
);
1491 EXPORT_SYMBOL(pci_add_new_bus
);
1492 EXPORT_SYMBOL(pci_scan_slot
);
1493 EXPORT_SYMBOL(pci_scan_bridge
);
1494 EXPORT_SYMBOL_GPL(pci_scan_child_bus
);
1497 static int __init
pci_sort_bf_cmp(const struct device
*d_a
, const struct device
*d_b
)
1499 const struct pci_dev
*a
= to_pci_dev(d_a
);
1500 const struct pci_dev
*b
= to_pci_dev(d_b
);
1502 if (pci_domain_nr(a
->bus
) < pci_domain_nr(b
->bus
)) return -1;
1503 else if (pci_domain_nr(a
->bus
) > pci_domain_nr(b
->bus
)) return 1;
1505 if (a
->bus
->number
< b
->bus
->number
) return -1;
1506 else if (a
->bus
->number
> b
->bus
->number
) return 1;
1508 if (a
->devfn
< b
->devfn
) return -1;
1509 else if (a
->devfn
> b
->devfn
) return 1;
1514 void __init
pci_sort_breadthfirst(void)
1516 bus_sort_breadthfirst(&pci_bus_type
, &pci_sort_bf_cmp
);