PM / sleep: Asynchronous threads for suspend_noirq
[linux/fpc-iii.git] / drivers / pci / probe.c
blob6e34498ec9f0269387c296e498174ccb29cbe3fb
1 /*
2 * probe.c - PCI detection and setup code
3 */
5 #include <linux/kernel.h>
6 #include <linux/delay.h>
7 #include <linux/init.h>
8 #include <linux/pci.h>
9 #include <linux/slab.h>
10 #include <linux/module.h>
11 #include <linux/cpumask.h>
12 #include <linux/pci-aspm.h>
13 #include <asm-generic/pci-bridge.h>
14 #include "pci.h"
16 #define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
17 #define CARDBUS_RESERVE_BUSNR 3
19 static struct resource busn_resource = {
20 .name = "PCI busn",
21 .start = 0,
22 .end = 255,
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;
34 struct resource res;
35 int domain_nr;
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)
44 return &r->res;
46 r = kzalloc(sizeof(*r), GFP_KERNEL);
47 if (!r)
48 return NULL;
50 r->domain_nr = domain_nr;
51 r->res.start = 0;
52 r->res.end = 0xff;
53 r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
55 list_add_tail(&r->list, &pci_domain_busn_res_list);
57 return &r->res;
60 static int find_anything(struct device *dev, void *data)
62 return 1;
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)
72 struct device *dev;
73 int no_devices;
75 dev = bus_find_device(&pci_bus_type, NULL, NULL, find_anything);
76 no_devices = (dev == NULL);
77 put_device(dev);
78 return no_devices;
80 EXPORT_SYMBOL(no_pci_devices);
83 * PCI Bus Class
85 static void release_pcibus_dev(struct device *dev)
87 struct pci_bus *pci_bus = to_pci_bus(dev);
89 if (pci_bus->bridge)
90 put_device(pci_bus->bridge);
91 pci_bus_remove_resources(pci_bus);
92 pci_release_bus_of_node(pci_bus);
93 kfree(pci_bus);
96 static struct class pcibus_class = {
97 .name = "pci_bus",
98 .dev_release = &release_pcibus_dev,
99 .dev_groups = pcibus_groups,
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 */
111 if (!size)
112 return 0;
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)
121 return 0;
123 return size;
126 static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
128 u32 mem_type;
129 unsigned long flags;
131 if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
132 flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
133 flags |= IORESOURCE_IO;
134 return flags;
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;
143 switch (mem_type) {
144 case PCI_BASE_ADDRESS_MEM_TYPE_32:
145 break;
146 case PCI_BASE_ADDRESS_MEM_TYPE_1M:
147 /* 1M mem BAR treated as 32-bit BAR */
148 break;
149 case PCI_BASE_ADDRESS_MEM_TYPE_64:
150 flags |= IORESOURCE_MEM_64;
151 break;
152 default:
153 /* mem unknown type treated as 32-bit BAR */
154 break;
156 return flags;
159 #define PCI_COMMAND_DECODE_ENABLE (PCI_COMMAND_MEMORY | PCI_COMMAND_IO)
162 * pci_read_base - read a PCI BAR
163 * @dev: the PCI device
164 * @type: type of the BAR
165 * @res: resource buffer to be filled in
166 * @pos: BAR position in the config space
168 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
170 int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
171 struct resource *res, unsigned int pos)
173 u32 l, sz, mask;
174 u16 orig_cmd;
175 struct pci_bus_region region, inverted_region;
176 bool bar_too_big = false, bar_disabled = false;
178 mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
180 /* No printks while decoding is disabled! */
181 if (!dev->mmio_always_on) {
182 pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
183 if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) {
184 pci_write_config_word(dev, PCI_COMMAND,
185 orig_cmd & ~PCI_COMMAND_DECODE_ENABLE);
189 res->name = pci_name(dev);
191 pci_read_config_dword(dev, pos, &l);
192 pci_write_config_dword(dev, pos, l | mask);
193 pci_read_config_dword(dev, pos, &sz);
194 pci_write_config_dword(dev, pos, l);
197 * All bits set in sz means the device isn't working properly.
198 * If the BAR isn't implemented, all bits must be 0. If it's a
199 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
200 * 1 must be clear.
202 if (!sz || sz == 0xffffffff)
203 goto fail;
206 * I don't know how l can have all bits set. Copied from old code.
207 * Maybe it fixes a bug on some ancient platform.
209 if (l == 0xffffffff)
210 l = 0;
212 if (type == pci_bar_unknown) {
213 res->flags = decode_bar(dev, l);
214 res->flags |= IORESOURCE_SIZEALIGN;
215 if (res->flags & IORESOURCE_IO) {
216 l &= PCI_BASE_ADDRESS_IO_MASK;
217 mask = PCI_BASE_ADDRESS_IO_MASK & (u32) IO_SPACE_LIMIT;
218 } else {
219 l &= PCI_BASE_ADDRESS_MEM_MASK;
220 mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
222 } else {
223 res->flags |= (l & IORESOURCE_ROM_ENABLE);
224 l &= PCI_ROM_ADDRESS_MASK;
225 mask = (u32)PCI_ROM_ADDRESS_MASK;
228 if (res->flags & IORESOURCE_MEM_64) {
229 u64 l64 = l;
230 u64 sz64 = sz;
231 u64 mask64 = mask | (u64)~0 << 32;
233 pci_read_config_dword(dev, pos + 4, &l);
234 pci_write_config_dword(dev, pos + 4, ~0);
235 pci_read_config_dword(dev, pos + 4, &sz);
236 pci_write_config_dword(dev, pos + 4, l);
238 l64 |= ((u64)l << 32);
239 sz64 |= ((u64)sz << 32);
241 sz64 = pci_size(l64, sz64, mask64);
243 if (!sz64)
244 goto fail;
246 if ((sizeof(resource_size_t) < 8) && (sz64 > 0x100000000ULL)) {
247 bar_too_big = true;
248 goto fail;
251 if ((sizeof(resource_size_t) < 8) && l) {
252 /* Address above 32-bit boundary; disable the BAR */
253 pci_write_config_dword(dev, pos, 0);
254 pci_write_config_dword(dev, pos + 4, 0);
255 region.start = 0;
256 region.end = sz64;
257 bar_disabled = true;
258 } else {
259 region.start = l64;
260 region.end = l64 + sz64;
262 } else {
263 sz = pci_size(l, sz, mask);
265 if (!sz)
266 goto fail;
268 region.start = l;
269 region.end = l + sz;
272 pcibios_bus_to_resource(dev->bus, res, &region);
273 pcibios_resource_to_bus(dev->bus, &inverted_region, res);
276 * If "A" is a BAR value (a bus address), "bus_to_resource(A)" is
277 * the corresponding resource address (the physical address used by
278 * the CPU. Converting that resource address back to a bus address
279 * should yield the original BAR value:
281 * resource_to_bus(bus_to_resource(A)) == A
283 * If it doesn't, CPU accesses to "bus_to_resource(A)" will not
284 * be claimed by the device.
286 if (inverted_region.start != region.start) {
287 dev_info(&dev->dev, "reg 0x%x: initial BAR value %pa invalid; forcing reassignment\n",
288 pos, &region.start);
289 res->flags |= IORESOURCE_UNSET;
290 res->end -= res->start;
291 res->start = 0;
294 goto out;
297 fail:
298 res->flags = 0;
299 out:
300 if (!dev->mmio_always_on &&
301 (orig_cmd & PCI_COMMAND_DECODE_ENABLE))
302 pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
304 if (bar_too_big)
305 dev_err(&dev->dev, "reg 0x%x: can't handle 64-bit BAR\n", pos);
306 if (res->flags && !bar_disabled)
307 dev_printk(KERN_DEBUG, &dev->dev, "reg 0x%x: %pR\n", pos, res);
309 return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
312 static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
314 unsigned int pos, reg;
316 for (pos = 0; pos < howmany; pos++) {
317 struct resource *res = &dev->resource[pos];
318 reg = PCI_BASE_ADDRESS_0 + (pos << 2);
319 pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
322 if (rom) {
323 struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
324 dev->rom_base_reg = rom;
325 res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
326 IORESOURCE_READONLY | IORESOURCE_CACHEABLE |
327 IORESOURCE_SIZEALIGN;
328 __pci_read_base(dev, pci_bar_mem32, res, rom);
332 static void pci_read_bridge_io(struct pci_bus *child)
334 struct pci_dev *dev = child->self;
335 u8 io_base_lo, io_limit_lo;
336 unsigned long io_mask, io_granularity, base, limit;
337 struct pci_bus_region region;
338 struct resource *res;
340 io_mask = PCI_IO_RANGE_MASK;
341 io_granularity = 0x1000;
342 if (dev->io_window_1k) {
343 /* Support 1K I/O space granularity */
344 io_mask = PCI_IO_1K_RANGE_MASK;
345 io_granularity = 0x400;
348 res = child->resource[0];
349 pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
350 pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
351 base = (io_base_lo & io_mask) << 8;
352 limit = (io_limit_lo & io_mask) << 8;
354 if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
355 u16 io_base_hi, io_limit_hi;
357 pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
358 pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
359 base |= ((unsigned long) io_base_hi << 16);
360 limit |= ((unsigned long) io_limit_hi << 16);
363 if (base <= limit) {
364 res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
365 region.start = base;
366 region.end = limit + io_granularity - 1;
367 pcibios_bus_to_resource(dev->bus, res, &region);
368 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
372 static void pci_read_bridge_mmio(struct pci_bus *child)
374 struct pci_dev *dev = child->self;
375 u16 mem_base_lo, mem_limit_lo;
376 unsigned long base, limit;
377 struct pci_bus_region region;
378 struct resource *res;
380 res = child->resource[1];
381 pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
382 pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
383 base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
384 limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
385 if (base <= limit) {
386 res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
387 region.start = base;
388 region.end = limit + 0xfffff;
389 pcibios_bus_to_resource(dev->bus, res, &region);
390 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
394 static void pci_read_bridge_mmio_pref(struct pci_bus *child)
396 struct pci_dev *dev = child->self;
397 u16 mem_base_lo, mem_limit_lo;
398 unsigned long base, limit;
399 struct pci_bus_region region;
400 struct resource *res;
402 res = child->resource[2];
403 pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
404 pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
405 base = ((unsigned long) mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
406 limit = ((unsigned long) mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
408 if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
409 u32 mem_base_hi, mem_limit_hi;
411 pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
412 pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
415 * Some bridges set the base > limit by default, and some
416 * (broken) BIOSes do not initialize them. If we find
417 * this, just assume they are not being used.
419 if (mem_base_hi <= mem_limit_hi) {
420 #if BITS_PER_LONG == 64
421 base |= ((unsigned long) mem_base_hi) << 32;
422 limit |= ((unsigned long) mem_limit_hi) << 32;
423 #else
424 if (mem_base_hi || mem_limit_hi) {
425 dev_err(&dev->dev, "can't handle 64-bit "
426 "address space for bridge\n");
427 return;
429 #endif
432 if (base <= limit) {
433 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
434 IORESOURCE_MEM | IORESOURCE_PREFETCH;
435 if (res->flags & PCI_PREF_RANGE_TYPE_64)
436 res->flags |= IORESOURCE_MEM_64;
437 region.start = base;
438 region.end = limit + 0xfffff;
439 pcibios_bus_to_resource(dev->bus, res, &region);
440 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
444 void pci_read_bridge_bases(struct pci_bus *child)
446 struct pci_dev *dev = child->self;
447 struct resource *res;
448 int i;
450 if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
451 return;
453 dev_info(&dev->dev, "PCI bridge to %pR%s\n",
454 &child->busn_res,
455 dev->transparent ? " (subtractive decode)" : "");
457 pci_bus_remove_resources(child);
458 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
459 child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
461 pci_read_bridge_io(child);
462 pci_read_bridge_mmio(child);
463 pci_read_bridge_mmio_pref(child);
465 if (dev->transparent) {
466 pci_bus_for_each_resource(child->parent, res, i) {
467 if (res) {
468 pci_bus_add_resource(child, res,
469 PCI_SUBTRACTIVE_DECODE);
470 dev_printk(KERN_DEBUG, &dev->dev,
471 " bridge window %pR (subtractive decode)\n",
472 res);
478 static struct pci_bus *pci_alloc_bus(void)
480 struct pci_bus *b;
482 b = kzalloc(sizeof(*b), GFP_KERNEL);
483 if (!b)
484 return NULL;
486 INIT_LIST_HEAD(&b->node);
487 INIT_LIST_HEAD(&b->children);
488 INIT_LIST_HEAD(&b->devices);
489 INIT_LIST_HEAD(&b->slots);
490 INIT_LIST_HEAD(&b->resources);
491 b->max_bus_speed = PCI_SPEED_UNKNOWN;
492 b->cur_bus_speed = PCI_SPEED_UNKNOWN;
493 return b;
496 static void pci_release_host_bridge_dev(struct device *dev)
498 struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
500 if (bridge->release_fn)
501 bridge->release_fn(bridge);
503 pci_free_resource_list(&bridge->windows);
505 kfree(bridge);
508 static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b)
510 struct pci_host_bridge *bridge;
512 bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
513 if (!bridge)
514 return NULL;
516 INIT_LIST_HEAD(&bridge->windows);
517 bridge->bus = b;
518 return bridge;
521 static const unsigned char pcix_bus_speed[] = {
522 PCI_SPEED_UNKNOWN, /* 0 */
523 PCI_SPEED_66MHz_PCIX, /* 1 */
524 PCI_SPEED_100MHz_PCIX, /* 2 */
525 PCI_SPEED_133MHz_PCIX, /* 3 */
526 PCI_SPEED_UNKNOWN, /* 4 */
527 PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
528 PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
529 PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
530 PCI_SPEED_UNKNOWN, /* 8 */
531 PCI_SPEED_66MHz_PCIX_266, /* 9 */
532 PCI_SPEED_100MHz_PCIX_266, /* A */
533 PCI_SPEED_133MHz_PCIX_266, /* B */
534 PCI_SPEED_UNKNOWN, /* C */
535 PCI_SPEED_66MHz_PCIX_533, /* D */
536 PCI_SPEED_100MHz_PCIX_533, /* E */
537 PCI_SPEED_133MHz_PCIX_533 /* F */
540 const unsigned char pcie_link_speed[] = {
541 PCI_SPEED_UNKNOWN, /* 0 */
542 PCIE_SPEED_2_5GT, /* 1 */
543 PCIE_SPEED_5_0GT, /* 2 */
544 PCIE_SPEED_8_0GT, /* 3 */
545 PCI_SPEED_UNKNOWN, /* 4 */
546 PCI_SPEED_UNKNOWN, /* 5 */
547 PCI_SPEED_UNKNOWN, /* 6 */
548 PCI_SPEED_UNKNOWN, /* 7 */
549 PCI_SPEED_UNKNOWN, /* 8 */
550 PCI_SPEED_UNKNOWN, /* 9 */
551 PCI_SPEED_UNKNOWN, /* A */
552 PCI_SPEED_UNKNOWN, /* B */
553 PCI_SPEED_UNKNOWN, /* C */
554 PCI_SPEED_UNKNOWN, /* D */
555 PCI_SPEED_UNKNOWN, /* E */
556 PCI_SPEED_UNKNOWN /* F */
559 void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
561 bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS];
563 EXPORT_SYMBOL_GPL(pcie_update_link_speed);
565 static unsigned char agp_speeds[] = {
566 AGP_UNKNOWN,
567 AGP_1X,
568 AGP_2X,
569 AGP_4X,
570 AGP_8X
573 static enum pci_bus_speed agp_speed(int agp3, int agpstat)
575 int index = 0;
577 if (agpstat & 4)
578 index = 3;
579 else if (agpstat & 2)
580 index = 2;
581 else if (agpstat & 1)
582 index = 1;
583 else
584 goto out;
586 if (agp3) {
587 index += 2;
588 if (index == 5)
589 index = 0;
592 out:
593 return agp_speeds[index];
597 static void pci_set_bus_speed(struct pci_bus *bus)
599 struct pci_dev *bridge = bus->self;
600 int pos;
602 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
603 if (!pos)
604 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
605 if (pos) {
606 u32 agpstat, agpcmd;
608 pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
609 bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
611 pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
612 bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
615 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
616 if (pos) {
617 u16 status;
618 enum pci_bus_speed max;
620 pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
621 &status);
623 if (status & PCI_X_SSTATUS_533MHZ) {
624 max = PCI_SPEED_133MHz_PCIX_533;
625 } else if (status & PCI_X_SSTATUS_266MHZ) {
626 max = PCI_SPEED_133MHz_PCIX_266;
627 } else if (status & PCI_X_SSTATUS_133MHZ) {
628 if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2) {
629 max = PCI_SPEED_133MHz_PCIX_ECC;
630 } else {
631 max = PCI_SPEED_133MHz_PCIX;
633 } else {
634 max = PCI_SPEED_66MHz_PCIX;
637 bus->max_bus_speed = max;
638 bus->cur_bus_speed = pcix_bus_speed[
639 (status & PCI_X_SSTATUS_FREQ) >> 6];
641 return;
644 if (pci_is_pcie(bridge)) {
645 u32 linkcap;
646 u16 linksta;
648 pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
649 bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
651 pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
652 pcie_update_link_speed(bus, linksta);
657 static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
658 struct pci_dev *bridge, int busnr)
660 struct pci_bus *child;
661 int i;
662 int ret;
665 * Allocate a new bus, and inherit stuff from the parent..
667 child = pci_alloc_bus();
668 if (!child)
669 return NULL;
671 child->parent = parent;
672 child->ops = parent->ops;
673 child->msi = parent->msi;
674 child->sysdata = parent->sysdata;
675 child->bus_flags = parent->bus_flags;
677 /* initialize some portions of the bus device, but don't register it
678 * now as the parent is not properly set up yet.
680 child->dev.class = &pcibus_class;
681 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
684 * Set up the primary, secondary and subordinate
685 * bus numbers.
687 child->number = child->busn_res.start = busnr;
688 child->primary = parent->busn_res.start;
689 child->busn_res.end = 0xff;
691 if (!bridge) {
692 child->dev.parent = parent->bridge;
693 goto add_dev;
696 child->self = bridge;
697 child->bridge = get_device(&bridge->dev);
698 child->dev.parent = child->bridge;
699 pci_set_bus_of_node(child);
700 pci_set_bus_speed(child);
702 /* Set up default resource pointers and names.. */
703 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
704 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
705 child->resource[i]->name = child->name;
707 bridge->subordinate = child;
709 add_dev:
710 ret = device_register(&child->dev);
711 WARN_ON(ret < 0);
713 pcibios_add_bus(child);
715 /* Create legacy_io and legacy_mem files for this bus */
716 pci_create_legacy_files(child);
718 return child;
721 struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr)
723 struct pci_bus *child;
725 child = pci_alloc_child_bus(parent, dev, busnr);
726 if (child) {
727 down_write(&pci_bus_sem);
728 list_add_tail(&child->node, &parent->children);
729 up_write(&pci_bus_sem);
731 return child;
734 static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
736 struct pci_bus *parent = child->parent;
738 /* Attempts to fix that up are really dangerous unless
739 we're going to re-assign all bus numbers. */
740 if (!pcibios_assign_all_busses())
741 return;
743 while (parent->parent && parent->busn_res.end < max) {
744 parent->busn_res.end = max;
745 pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);
746 parent = parent->parent;
751 * If it's a bridge, configure it and scan the bus behind it.
752 * For CardBus bridges, we don't scan behind as the devices will
753 * be handled by the bridge driver itself.
755 * We need to process bridges in two passes -- first we scan those
756 * already configured by the BIOS and after we are done with all of
757 * them, we proceed to assigning numbers to the remaining buses in
758 * order to avoid overlaps between old and new bus numbers.
760 int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
762 struct pci_bus *child;
763 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
764 u32 buses, i, j = 0;
765 u16 bctl;
766 u8 primary, secondary, subordinate;
767 int broken = 0;
769 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
770 primary = buses & 0xFF;
771 secondary = (buses >> 8) & 0xFF;
772 subordinate = (buses >> 16) & 0xFF;
774 dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
775 secondary, subordinate, pass);
777 if (!primary && (primary != bus->number) && secondary && subordinate) {
778 dev_warn(&dev->dev, "Primary bus is hard wired to 0\n");
779 primary = bus->number;
782 /* Check if setup is sensible at all */
783 if (!pass &&
784 (primary != bus->number || secondary <= bus->number ||
785 secondary > subordinate)) {
786 dev_info(&dev->dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
787 secondary, subordinate);
788 broken = 1;
791 /* Disable MasterAbortMode during probing to avoid reporting
792 of bus errors (in some architectures) */
793 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
794 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
795 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
797 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
798 !is_cardbus && !broken) {
799 unsigned int cmax;
801 * Bus already configured by firmware, process it in the first
802 * pass and just note the configuration.
804 if (pass)
805 goto out;
808 * If we already got to this bus through a different bridge,
809 * don't re-add it. This can happen with the i450NX chipset.
811 * However, we continue to descend down the hierarchy and
812 * scan remaining child buses.
814 child = pci_find_bus(pci_domain_nr(bus), secondary);
815 if (!child) {
816 child = pci_add_new_bus(bus, dev, secondary);
817 if (!child)
818 goto out;
819 child->primary = primary;
820 pci_bus_insert_busn_res(child, secondary, subordinate);
821 child->bridge_ctl = bctl;
824 cmax = pci_scan_child_bus(child);
825 if (cmax > max)
826 max = cmax;
827 if (child->busn_res.end > max)
828 max = child->busn_res.end;
829 } else {
831 * We need to assign a number to this bus which we always
832 * do in the second pass.
834 if (!pass) {
835 if (pcibios_assign_all_busses() || broken)
836 /* Temporarily disable forwarding of the
837 configuration cycles on all bridges in
838 this bus segment to avoid possible
839 conflicts in the second pass between two
840 bridges programmed with overlapping
841 bus ranges. */
842 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
843 buses & ~0xffffff);
844 goto out;
847 /* Clear errors */
848 pci_write_config_word(dev, PCI_STATUS, 0xffff);
850 /* Prevent assigning a bus number that already exists.
851 * This can happen when a bridge is hot-plugged, so in
852 * this case we only re-scan this bus. */
853 child = pci_find_bus(pci_domain_nr(bus), max+1);
854 if (!child) {
855 child = pci_add_new_bus(bus, dev, ++max);
856 if (!child)
857 goto out;
858 pci_bus_insert_busn_res(child, max, 0xff);
860 buses = (buses & 0xff000000)
861 | ((unsigned int)(child->primary) << 0)
862 | ((unsigned int)(child->busn_res.start) << 8)
863 | ((unsigned int)(child->busn_res.end) << 16);
866 * yenta.c forces a secondary latency timer of 176.
867 * Copy that behaviour here.
869 if (is_cardbus) {
870 buses &= ~0xff000000;
871 buses |= CARDBUS_LATENCY_TIMER << 24;
875 * We need to blast all three values with a single write.
877 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
879 if (!is_cardbus) {
880 child->bridge_ctl = bctl;
882 * Adjust subordinate busnr in parent buses.
883 * We do this before scanning for children because
884 * some devices may not be detected if the bios
885 * was lazy.
887 pci_fixup_parent_subordinate_busnr(child, max);
888 /* Now we can scan all subordinate buses... */
889 max = pci_scan_child_bus(child);
891 * now fix it up again since we have found
892 * the real value of max.
894 pci_fixup_parent_subordinate_busnr(child, max);
895 } else {
897 * For CardBus bridges, we leave 4 bus numbers
898 * as cards with a PCI-to-PCI bridge can be
899 * inserted later.
901 for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
902 struct pci_bus *parent = bus;
903 if (pci_find_bus(pci_domain_nr(bus),
904 max+i+1))
905 break;
906 while (parent->parent) {
907 if ((!pcibios_assign_all_busses()) &&
908 (parent->busn_res.end > max) &&
909 (parent->busn_res.end <= max+i)) {
910 j = 1;
912 parent = parent->parent;
914 if (j) {
916 * Often, there are two cardbus bridges
917 * -- try to leave one valid bus number
918 * for each one.
920 i /= 2;
921 break;
924 max += i;
925 pci_fixup_parent_subordinate_busnr(child, max);
928 * Set the subordinate bus number to its real value.
930 pci_bus_update_busn_res_end(child, max);
931 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
934 sprintf(child->name,
935 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
936 pci_domain_nr(bus), child->number);
938 /* Has only triggered on CardBus, fixup is in yenta_socket */
939 while (bus->parent) {
940 if ((child->busn_res.end > bus->busn_res.end) ||
941 (child->number > bus->busn_res.end) ||
942 (child->number < bus->number) ||
943 (child->busn_res.end < bus->number)) {
944 dev_info(&child->dev, "%pR %s "
945 "hidden behind%s bridge %s %pR\n",
946 &child->busn_res,
947 (bus->number > child->busn_res.end &&
948 bus->busn_res.end < child->number) ?
949 "wholly" : "partially",
950 bus->self->transparent ? " transparent" : "",
951 dev_name(&bus->dev),
952 &bus->busn_res);
954 bus = bus->parent;
957 out:
958 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
960 return max;
964 * Read interrupt line and base address registers.
965 * The architecture-dependent code can tweak these, of course.
967 static void pci_read_irq(struct pci_dev *dev)
969 unsigned char irq;
971 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
972 dev->pin = irq;
973 if (irq)
974 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
975 dev->irq = irq;
978 void set_pcie_port_type(struct pci_dev *pdev)
980 int pos;
981 u16 reg16;
983 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
984 if (!pos)
985 return;
986 pdev->pcie_cap = pos;
987 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, &reg16);
988 pdev->pcie_flags_reg = reg16;
989 pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, &reg16);
990 pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
993 void set_pcie_hotplug_bridge(struct pci_dev *pdev)
995 u32 reg32;
997 pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &reg32);
998 if (reg32 & PCI_EXP_SLTCAP_HPC)
999 pdev->is_hotplug_bridge = 1;
1004 * pci_cfg_space_size - get the configuration space size of the PCI device.
1005 * @dev: PCI device
1007 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1008 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1009 * access it. Maybe we don't have a way to generate extended config space
1010 * accesses, or the device is behind a reverse Express bridge. So we try
1011 * reading the dword at 0x100 which must either be 0 or a valid extended
1012 * capability header.
1014 static int pci_cfg_space_size_ext(struct pci_dev *dev)
1016 u32 status;
1017 int pos = PCI_CFG_SPACE_SIZE;
1019 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1020 goto fail;
1021 if (status == 0xffffffff)
1022 goto fail;
1024 return PCI_CFG_SPACE_EXP_SIZE;
1026 fail:
1027 return PCI_CFG_SPACE_SIZE;
1030 int pci_cfg_space_size(struct pci_dev *dev)
1032 int pos;
1033 u32 status;
1034 u16 class;
1036 class = dev->class >> 8;
1037 if (class == PCI_CLASS_BRIDGE_HOST)
1038 return pci_cfg_space_size_ext(dev);
1040 if (!pci_is_pcie(dev)) {
1041 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1042 if (!pos)
1043 goto fail;
1045 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1046 if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
1047 goto fail;
1050 return pci_cfg_space_size_ext(dev);
1052 fail:
1053 return PCI_CFG_SPACE_SIZE;
1056 #define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
1059 * pci_setup_device - fill in class and map information of a device
1060 * @dev: the device structure to fill
1062 * Initialize the device structure with information about the device's
1063 * vendor,class,memory and IO-space addresses,IRQ lines etc.
1064 * Called at initialisation of the PCI subsystem and by CardBus services.
1065 * Returns 0 on success and negative if unknown type of device (not normal,
1066 * bridge or CardBus).
1068 int pci_setup_device(struct pci_dev *dev)
1070 u32 class;
1071 u8 hdr_type;
1072 struct pci_slot *slot;
1073 int pos = 0;
1074 struct pci_bus_region region;
1075 struct resource *res;
1077 if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
1078 return -EIO;
1080 dev->sysdata = dev->bus->sysdata;
1081 dev->dev.parent = dev->bus->bridge;
1082 dev->dev.bus = &pci_bus_type;
1083 dev->hdr_type = hdr_type & 0x7f;
1084 dev->multifunction = !!(hdr_type & 0x80);
1085 dev->error_state = pci_channel_io_normal;
1086 set_pcie_port_type(dev);
1088 list_for_each_entry(slot, &dev->bus->slots, list)
1089 if (PCI_SLOT(dev->devfn) == slot->number)
1090 dev->slot = slot;
1092 /* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
1093 set this higher, assuming the system even supports it. */
1094 dev->dma_mask = 0xffffffff;
1096 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
1097 dev->bus->number, PCI_SLOT(dev->devfn),
1098 PCI_FUNC(dev->devfn));
1100 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
1101 dev->revision = class & 0xff;
1102 dev->class = class >> 8; /* upper 3 bytes */
1104 dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %02x class %#08x\n",
1105 dev->vendor, dev->device, dev->hdr_type, dev->class);
1107 /* need to have dev->class ready */
1108 dev->cfg_size = pci_cfg_space_size(dev);
1110 /* "Unknown power state" */
1111 dev->current_state = PCI_UNKNOWN;
1113 /* Early fixups, before probing the BARs */
1114 pci_fixup_device(pci_fixup_early, dev);
1115 /* device class may be changed after fixup */
1116 class = dev->class >> 8;
1118 switch (dev->hdr_type) { /* header type */
1119 case PCI_HEADER_TYPE_NORMAL: /* standard header */
1120 if (class == PCI_CLASS_BRIDGE_PCI)
1121 goto bad;
1122 pci_read_irq(dev);
1123 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1124 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1125 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
1128 * Do the ugly legacy mode stuff here rather than broken chip
1129 * quirk code. Legacy mode ATA controllers have fixed
1130 * addresses. These are not always echoed in BAR0-3, and
1131 * BAR0-3 in a few cases contain junk!
1133 if (class == PCI_CLASS_STORAGE_IDE) {
1134 u8 progif;
1135 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1136 if ((progif & 1) == 0) {
1137 region.start = 0x1F0;
1138 region.end = 0x1F7;
1139 res = &dev->resource[0];
1140 res->flags = LEGACY_IO_RESOURCE;
1141 pcibios_bus_to_resource(dev->bus, res, &region);
1142 region.start = 0x3F6;
1143 region.end = 0x3F6;
1144 res = &dev->resource[1];
1145 res->flags = LEGACY_IO_RESOURCE;
1146 pcibios_bus_to_resource(dev->bus, res, &region);
1148 if ((progif & 4) == 0) {
1149 region.start = 0x170;
1150 region.end = 0x177;
1151 res = &dev->resource[2];
1152 res->flags = LEGACY_IO_RESOURCE;
1153 pcibios_bus_to_resource(dev->bus, res, &region);
1154 region.start = 0x376;
1155 region.end = 0x376;
1156 res = &dev->resource[3];
1157 res->flags = LEGACY_IO_RESOURCE;
1158 pcibios_bus_to_resource(dev->bus, res, &region);
1161 break;
1163 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1164 if (class != PCI_CLASS_BRIDGE_PCI)
1165 goto bad;
1166 /* The PCI-to-PCI bridge spec requires that subtractive
1167 decoding (i.e. transparent) bridge must have programming
1168 interface code of 0x01. */
1169 pci_read_irq(dev);
1170 dev->transparent = ((dev->class & 0xff) == 1);
1171 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1172 set_pcie_hotplug_bridge(dev);
1173 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1174 if (pos) {
1175 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1176 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1178 break;
1180 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1181 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1182 goto bad;
1183 pci_read_irq(dev);
1184 pci_read_bases(dev, 1, 0);
1185 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1186 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1187 break;
1189 default: /* unknown header */
1190 dev_err(&dev->dev, "unknown header type %02x, "
1191 "ignoring device\n", dev->hdr_type);
1192 return -EIO;
1194 bad:
1195 dev_err(&dev->dev, "ignoring class %#08x (doesn't match header "
1196 "type %02x)\n", dev->class, dev->hdr_type);
1197 dev->class = PCI_CLASS_NOT_DEFINED;
1200 /* We found a fine healthy device, go go go... */
1201 return 0;
1204 static void pci_release_capabilities(struct pci_dev *dev)
1206 pci_vpd_release(dev);
1207 pci_iov_release(dev);
1208 pci_free_cap_save_buffers(dev);
1212 * pci_release_dev - free a pci device structure when all users of it are finished.
1213 * @dev: device that's been disconnected
1215 * Will be called only by the device core when all users of this pci device are
1216 * done.
1218 static void pci_release_dev(struct device *dev)
1220 struct pci_dev *pci_dev;
1222 pci_dev = to_pci_dev(dev);
1223 pci_release_capabilities(pci_dev);
1224 pci_release_of_node(pci_dev);
1225 pcibios_release_device(pci_dev);
1226 pci_bus_put(pci_dev->bus);
1227 kfree(pci_dev);
1230 struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
1232 struct pci_dev *dev;
1234 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
1235 if (!dev)
1236 return NULL;
1238 INIT_LIST_HEAD(&dev->bus_list);
1239 dev->dev.type = &pci_dev_type;
1240 dev->bus = pci_bus_get(bus);
1242 return dev;
1244 EXPORT_SYMBOL(pci_alloc_dev);
1246 bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
1247 int crs_timeout)
1249 int delay = 1;
1251 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1252 return false;
1254 /* some broken boards return 0 or ~0 if a slot is empty: */
1255 if (*l == 0xffffffff || *l == 0x00000000 ||
1256 *l == 0x0000ffff || *l == 0xffff0000)
1257 return false;
1259 /* Configuration request Retry Status */
1260 while (*l == 0xffff0001) {
1261 if (!crs_timeout)
1262 return false;
1264 msleep(delay);
1265 delay *= 2;
1266 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1267 return false;
1268 /* Card hasn't responded in 60 seconds? Must be stuck. */
1269 if (delay > crs_timeout) {
1270 printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not "
1271 "responding\n", pci_domain_nr(bus),
1272 bus->number, PCI_SLOT(devfn),
1273 PCI_FUNC(devfn));
1274 return false;
1278 return true;
1280 EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
1283 * Read the config data for a PCI device, sanity-check it
1284 * and fill in the dev structure...
1286 static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
1288 struct pci_dev *dev;
1289 u32 l;
1291 if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
1292 return NULL;
1294 dev = pci_alloc_dev(bus);
1295 if (!dev)
1296 return NULL;
1298 dev->devfn = devfn;
1299 dev->vendor = l & 0xffff;
1300 dev->device = (l >> 16) & 0xffff;
1302 pci_set_of_node(dev);
1304 if (pci_setup_device(dev)) {
1305 pci_bus_put(dev->bus);
1306 kfree(dev);
1307 return NULL;
1310 return dev;
1313 static void pci_init_capabilities(struct pci_dev *dev)
1315 /* MSI/MSI-X list */
1316 pci_msi_init_pci_dev(dev);
1318 /* Buffers for saving PCIe and PCI-X capabilities */
1319 pci_allocate_cap_save_buffers(dev);
1321 /* Power Management */
1322 pci_pm_init(dev);
1324 /* Vital Product Data */
1325 pci_vpd_pci22_init(dev);
1327 /* Alternative Routing-ID Forwarding */
1328 pci_configure_ari(dev);
1330 /* Single Root I/O Virtualization */
1331 pci_iov_init(dev);
1333 /* Enable ACS P2P upstream forwarding */
1334 pci_enable_acs(dev);
1337 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
1339 int ret;
1341 device_initialize(&dev->dev);
1342 dev->dev.release = pci_release_dev;
1344 set_dev_node(&dev->dev, pcibus_to_node(bus));
1345 dev->dev.dma_mask = &dev->dma_mask;
1346 dev->dev.dma_parms = &dev->dma_parms;
1347 dev->dev.coherent_dma_mask = 0xffffffffull;
1349 pci_set_dma_max_seg_size(dev, 65536);
1350 pci_set_dma_seg_boundary(dev, 0xffffffff);
1352 /* Fix up broken headers */
1353 pci_fixup_device(pci_fixup_header, dev);
1355 /* moved out from quirk header fixup code */
1356 pci_reassigndev_resource_alignment(dev);
1358 /* Clear the state_saved flag. */
1359 dev->state_saved = false;
1361 /* Initialize various capabilities */
1362 pci_init_capabilities(dev);
1365 * Add the device to our list of discovered devices
1366 * and the bus list for fixup functions, etc.
1368 down_write(&pci_bus_sem);
1369 list_add_tail(&dev->bus_list, &bus->devices);
1370 up_write(&pci_bus_sem);
1372 ret = pcibios_add_device(dev);
1373 WARN_ON(ret < 0);
1375 /* Notifier could use PCI capabilities */
1376 dev->match_driver = false;
1377 ret = device_add(&dev->dev);
1378 WARN_ON(ret < 0);
1381 struct pci_dev *__ref pci_scan_single_device(struct pci_bus *bus, int devfn)
1383 struct pci_dev *dev;
1385 dev = pci_get_slot(bus, devfn);
1386 if (dev) {
1387 pci_dev_put(dev);
1388 return dev;
1391 dev = pci_scan_device(bus, devfn);
1392 if (!dev)
1393 return NULL;
1395 pci_device_add(dev, bus);
1397 return dev;
1399 EXPORT_SYMBOL(pci_scan_single_device);
1401 static unsigned next_fn(struct pci_bus *bus, struct pci_dev *dev, unsigned fn)
1403 int pos;
1404 u16 cap = 0;
1405 unsigned next_fn;
1407 if (pci_ari_enabled(bus)) {
1408 if (!dev)
1409 return 0;
1410 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1411 if (!pos)
1412 return 0;
1414 pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap);
1415 next_fn = PCI_ARI_CAP_NFN(cap);
1416 if (next_fn <= fn)
1417 return 0; /* protect against malformed list */
1419 return next_fn;
1422 /* dev may be NULL for non-contiguous multifunction devices */
1423 if (!dev || dev->multifunction)
1424 return (fn + 1) % 8;
1426 return 0;
1429 static int only_one_child(struct pci_bus *bus)
1431 struct pci_dev *parent = bus->self;
1433 if (!parent || !pci_is_pcie(parent))
1434 return 0;
1435 if (pci_pcie_type(parent) == PCI_EXP_TYPE_ROOT_PORT)
1436 return 1;
1437 if (pci_pcie_type(parent) == PCI_EXP_TYPE_DOWNSTREAM &&
1438 !pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
1439 return 1;
1440 return 0;
1444 * pci_scan_slot - scan a PCI slot on a bus for devices.
1445 * @bus: PCI bus to scan
1446 * @devfn: slot number to scan (must have zero function.)
1448 * Scan a PCI slot on the specified PCI bus for devices, adding
1449 * discovered devices to the @bus->devices list. New devices
1450 * will not have is_added set.
1452 * Returns the number of new devices found.
1454 int pci_scan_slot(struct pci_bus *bus, int devfn)
1456 unsigned fn, nr = 0;
1457 struct pci_dev *dev;
1459 if (only_one_child(bus) && (devfn > 0))
1460 return 0; /* Already scanned the entire slot */
1462 dev = pci_scan_single_device(bus, devfn);
1463 if (!dev)
1464 return 0;
1465 if (!dev->is_added)
1466 nr++;
1468 for (fn = next_fn(bus, dev, 0); fn > 0; fn = next_fn(bus, dev, fn)) {
1469 dev = pci_scan_single_device(bus, devfn + fn);
1470 if (dev) {
1471 if (!dev->is_added)
1472 nr++;
1473 dev->multifunction = 1;
1477 /* only one slot has pcie device */
1478 if (bus->self && nr)
1479 pcie_aspm_init_link_state(bus->self);
1481 return nr;
1484 static int pcie_find_smpss(struct pci_dev *dev, void *data)
1486 u8 *smpss = data;
1488 if (!pci_is_pcie(dev))
1489 return 0;
1492 * We don't have a way to change MPS settings on devices that have
1493 * drivers attached. A hot-added device might support only the minimum
1494 * MPS setting (MPS=128). Therefore, if the fabric contains a bridge
1495 * where devices may be hot-added, we limit the fabric MPS to 128 so
1496 * hot-added devices will work correctly.
1498 * However, if we hot-add a device to a slot directly below a Root
1499 * Port, it's impossible for there to be other existing devices below
1500 * the port. We don't limit the MPS in this case because we can
1501 * reconfigure MPS on both the Root Port and the hot-added device,
1502 * and there are no other devices involved.
1504 * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
1506 if (dev->is_hotplug_bridge &&
1507 pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
1508 *smpss = 0;
1510 if (*smpss > dev->pcie_mpss)
1511 *smpss = dev->pcie_mpss;
1513 return 0;
1516 static void pcie_write_mps(struct pci_dev *dev, int mps)
1518 int rc;
1520 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
1521 mps = 128 << dev->pcie_mpss;
1523 if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
1524 dev->bus->self)
1525 /* For "Performance", the assumption is made that
1526 * downstream communication will never be larger than
1527 * the MRRS. So, the MPS only needs to be configured
1528 * for the upstream communication. This being the case,
1529 * walk from the top down and set the MPS of the child
1530 * to that of the parent bus.
1532 * Configure the device MPS with the smaller of the
1533 * device MPSS or the bridge MPS (which is assumed to be
1534 * properly configured at this point to the largest
1535 * allowable MPS based on its parent bus).
1537 mps = min(mps, pcie_get_mps(dev->bus->self));
1540 rc = pcie_set_mps(dev, mps);
1541 if (rc)
1542 dev_err(&dev->dev, "Failed attempting to set the MPS\n");
1545 static void pcie_write_mrrs(struct pci_dev *dev)
1547 int rc, mrrs;
1549 /* In the "safe" case, do not configure the MRRS. There appear to be
1550 * issues with setting MRRS to 0 on a number of devices.
1552 if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
1553 return;
1555 /* For Max performance, the MRRS must be set to the largest supported
1556 * value. However, it cannot be configured larger than the MPS the
1557 * device or the bus can support. This should already be properly
1558 * configured by a prior call to pcie_write_mps.
1560 mrrs = pcie_get_mps(dev);
1562 /* MRRS is a R/W register. Invalid values can be written, but a
1563 * subsequent read will verify if the value is acceptable or not.
1564 * If the MRRS value provided is not acceptable (e.g., too large),
1565 * shrink the value until it is acceptable to the HW.
1567 while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
1568 rc = pcie_set_readrq(dev, mrrs);
1569 if (!rc)
1570 break;
1572 dev_warn(&dev->dev, "Failed attempting to set the MRRS\n");
1573 mrrs /= 2;
1576 if (mrrs < 128)
1577 dev_err(&dev->dev, "MRRS was unable to be configured with a "
1578 "safe value. If problems are experienced, try running "
1579 "with pci=pcie_bus_safe.\n");
1582 static void pcie_bus_detect_mps(struct pci_dev *dev)
1584 struct pci_dev *bridge = dev->bus->self;
1585 int mps, p_mps;
1587 if (!bridge)
1588 return;
1590 mps = pcie_get_mps(dev);
1591 p_mps = pcie_get_mps(bridge);
1593 if (mps != p_mps)
1594 dev_warn(&dev->dev, "Max Payload Size %d, but upstream %s set to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
1595 mps, pci_name(bridge), p_mps);
1598 static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
1600 int mps, orig_mps;
1602 if (!pci_is_pcie(dev))
1603 return 0;
1605 if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
1606 pcie_bus_detect_mps(dev);
1607 return 0;
1610 mps = 128 << *(u8 *)data;
1611 orig_mps = pcie_get_mps(dev);
1613 pcie_write_mps(dev, mps);
1614 pcie_write_mrrs(dev);
1616 dev_info(&dev->dev, "Max Payload Size set to %4d/%4d (was %4d), "
1617 "Max Read Rq %4d\n", pcie_get_mps(dev), 128 << dev->pcie_mpss,
1618 orig_mps, pcie_get_readrq(dev));
1620 return 0;
1623 /* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down,
1624 * parents then children fashion. If this changes, then this code will not
1625 * work as designed.
1627 void pcie_bus_configure_settings(struct pci_bus *bus)
1629 u8 smpss;
1631 if (!bus->self)
1632 return;
1634 if (!pci_is_pcie(bus->self))
1635 return;
1637 /* FIXME - Peer to peer DMA is possible, though the endpoint would need
1638 * to be aware of the MPS of the destination. To work around this,
1639 * simply force the MPS of the entire system to the smallest possible.
1641 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
1642 smpss = 0;
1644 if (pcie_bus_config == PCIE_BUS_SAFE) {
1645 smpss = bus->self->pcie_mpss;
1647 pcie_find_smpss(bus->self, &smpss);
1648 pci_walk_bus(bus, pcie_find_smpss, &smpss);
1651 pcie_bus_configure_set(bus->self, &smpss);
1652 pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
1654 EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
1656 unsigned int pci_scan_child_bus(struct pci_bus *bus)
1658 unsigned int devfn, pass, max = bus->busn_res.start;
1659 struct pci_dev *dev;
1661 dev_dbg(&bus->dev, "scanning bus\n");
1663 /* Go find them, Rover! */
1664 for (devfn = 0; devfn < 0x100; devfn += 8)
1665 pci_scan_slot(bus, devfn);
1667 /* Reserve buses for SR-IOV capability. */
1668 max += pci_iov_bus_range(bus);
1671 * After performing arch-dependent fixup of the bus, look behind
1672 * all PCI-to-PCI bridges on this bus.
1674 if (!bus->is_added) {
1675 dev_dbg(&bus->dev, "fixups for bus\n");
1676 pcibios_fixup_bus(bus);
1677 bus->is_added = 1;
1680 for (pass=0; pass < 2; pass++)
1681 list_for_each_entry(dev, &bus->devices, bus_list) {
1682 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
1683 dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
1684 max = pci_scan_bridge(bus, dev, max, pass);
1688 * We've scanned the bus and so we know all about what's on
1689 * the other side of any bridges that may be on this bus plus
1690 * any devices.
1692 * Return how far we've got finding sub-buses.
1694 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
1695 return max;
1699 * pcibios_root_bridge_prepare - Platform-specific host bridge setup.
1700 * @bridge: Host bridge to set up.
1702 * Default empty implementation. Replace with an architecture-specific setup
1703 * routine, if necessary.
1705 int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
1707 return 0;
1710 void __weak pcibios_add_bus(struct pci_bus *bus)
1714 void __weak pcibios_remove_bus(struct pci_bus *bus)
1718 struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
1719 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1721 int error;
1722 struct pci_host_bridge *bridge;
1723 struct pci_bus *b, *b2;
1724 struct pci_host_bridge_window *window, *n;
1725 struct resource *res;
1726 resource_size_t offset;
1727 char bus_addr[64];
1728 char *fmt;
1730 b = pci_alloc_bus();
1731 if (!b)
1732 return NULL;
1734 b->sysdata = sysdata;
1735 b->ops = ops;
1736 b->number = b->busn_res.start = bus;
1737 b2 = pci_find_bus(pci_domain_nr(b), bus);
1738 if (b2) {
1739 /* If we already got to this bus through a different bridge, ignore it */
1740 dev_dbg(&b2->dev, "bus already known\n");
1741 goto err_out;
1744 bridge = pci_alloc_host_bridge(b);
1745 if (!bridge)
1746 goto err_out;
1748 bridge->dev.parent = parent;
1749 bridge->dev.release = pci_release_host_bridge_dev;
1750 dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
1751 error = pcibios_root_bridge_prepare(bridge);
1752 if (error) {
1753 kfree(bridge);
1754 goto err_out;
1757 error = device_register(&bridge->dev);
1758 if (error) {
1759 put_device(&bridge->dev);
1760 goto err_out;
1762 b->bridge = get_device(&bridge->dev);
1763 device_enable_async_suspend(b->bridge);
1764 pci_set_bus_of_node(b);
1766 if (!parent)
1767 set_dev_node(b->bridge, pcibus_to_node(b));
1769 b->dev.class = &pcibus_class;
1770 b->dev.parent = b->bridge;
1771 dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
1772 error = device_register(&b->dev);
1773 if (error)
1774 goto class_dev_reg_err;
1776 pcibios_add_bus(b);
1778 /* Create legacy_io and legacy_mem files for this bus */
1779 pci_create_legacy_files(b);
1781 if (parent)
1782 dev_info(parent, "PCI host bridge to bus %s\n", dev_name(&b->dev));
1783 else
1784 printk(KERN_INFO "PCI host bridge to bus %s\n", dev_name(&b->dev));
1786 /* Add initial resources to the bus */
1787 list_for_each_entry_safe(window, n, resources, list) {
1788 list_move_tail(&window->list, &bridge->windows);
1789 res = window->res;
1790 offset = window->offset;
1791 if (res->flags & IORESOURCE_BUS)
1792 pci_bus_insert_busn_res(b, bus, res->end);
1793 else
1794 pci_bus_add_resource(b, res, 0);
1795 if (offset) {
1796 if (resource_type(res) == IORESOURCE_IO)
1797 fmt = " (bus address [%#06llx-%#06llx])";
1798 else
1799 fmt = " (bus address [%#010llx-%#010llx])";
1800 snprintf(bus_addr, sizeof(bus_addr), fmt,
1801 (unsigned long long) (res->start - offset),
1802 (unsigned long long) (res->end - offset));
1803 } else
1804 bus_addr[0] = '\0';
1805 dev_info(&b->dev, "root bus resource %pR%s\n", res, bus_addr);
1808 down_write(&pci_bus_sem);
1809 list_add_tail(&b->node, &pci_root_buses);
1810 up_write(&pci_bus_sem);
1812 return b;
1814 class_dev_reg_err:
1815 put_device(&bridge->dev);
1816 device_unregister(&bridge->dev);
1817 err_out:
1818 kfree(b);
1819 return NULL;
1822 int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
1824 struct resource *res = &b->busn_res;
1825 struct resource *parent_res, *conflict;
1827 res->start = bus;
1828 res->end = bus_max;
1829 res->flags = IORESOURCE_BUS;
1831 if (!pci_is_root_bus(b))
1832 parent_res = &b->parent->busn_res;
1833 else {
1834 parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
1835 res->flags |= IORESOURCE_PCI_FIXED;
1838 conflict = insert_resource_conflict(parent_res, res);
1840 if (conflict)
1841 dev_printk(KERN_DEBUG, &b->dev,
1842 "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
1843 res, pci_is_root_bus(b) ? "domain " : "",
1844 parent_res, conflict->name, conflict);
1846 return conflict == NULL;
1849 int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
1851 struct resource *res = &b->busn_res;
1852 struct resource old_res = *res;
1853 resource_size_t size;
1854 int ret;
1856 if (res->start > bus_max)
1857 return -EINVAL;
1859 size = bus_max - res->start + 1;
1860 ret = adjust_resource(res, res->start, size);
1861 dev_printk(KERN_DEBUG, &b->dev,
1862 "busn_res: %pR end %s updated to %02x\n",
1863 &old_res, ret ? "can not be" : "is", bus_max);
1865 if (!ret && !res->parent)
1866 pci_bus_insert_busn_res(b, res->start, res->end);
1868 return ret;
1871 void pci_bus_release_busn_res(struct pci_bus *b)
1873 struct resource *res = &b->busn_res;
1874 int ret;
1876 if (!res->flags || !res->parent)
1877 return;
1879 ret = release_resource(res);
1880 dev_printk(KERN_DEBUG, &b->dev,
1881 "busn_res: %pR %s released\n",
1882 res, ret ? "can not be" : "is");
1885 struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
1886 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1888 struct pci_host_bridge_window *window;
1889 bool found = false;
1890 struct pci_bus *b;
1891 int max;
1893 list_for_each_entry(window, resources, list)
1894 if (window->res->flags & IORESOURCE_BUS) {
1895 found = true;
1896 break;
1899 b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
1900 if (!b)
1901 return NULL;
1903 if (!found) {
1904 dev_info(&b->dev,
1905 "No busn resource found for root bus, will use [bus %02x-ff]\n",
1906 bus);
1907 pci_bus_insert_busn_res(b, bus, 255);
1910 max = pci_scan_child_bus(b);
1912 if (!found)
1913 pci_bus_update_busn_res_end(b, max);
1915 pci_bus_add_devices(b);
1916 return b;
1918 EXPORT_SYMBOL(pci_scan_root_bus);
1920 /* Deprecated; use pci_scan_root_bus() instead */
1921 struct pci_bus *pci_scan_bus_parented(struct device *parent,
1922 int bus, struct pci_ops *ops, void *sysdata)
1924 LIST_HEAD(resources);
1925 struct pci_bus *b;
1927 pci_add_resource(&resources, &ioport_resource);
1928 pci_add_resource(&resources, &iomem_resource);
1929 pci_add_resource(&resources, &busn_resource);
1930 b = pci_create_root_bus(parent, bus, ops, sysdata, &resources);
1931 if (b)
1932 pci_scan_child_bus(b);
1933 else
1934 pci_free_resource_list(&resources);
1935 return b;
1937 EXPORT_SYMBOL(pci_scan_bus_parented);
1939 struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
1940 void *sysdata)
1942 LIST_HEAD(resources);
1943 struct pci_bus *b;
1945 pci_add_resource(&resources, &ioport_resource);
1946 pci_add_resource(&resources, &iomem_resource);
1947 pci_add_resource(&resources, &busn_resource);
1948 b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
1949 if (b) {
1950 pci_scan_child_bus(b);
1951 pci_bus_add_devices(b);
1952 } else {
1953 pci_free_resource_list(&resources);
1955 return b;
1957 EXPORT_SYMBOL(pci_scan_bus);
1960 * pci_rescan_bus_bridge_resize - scan a PCI bus for devices.
1961 * @bridge: PCI bridge for the bus to scan
1963 * Scan a PCI bus and child buses for new devices, add them,
1964 * and enable them, resizing bridge mmio/io resource if necessary
1965 * and possible. The caller must ensure the child devices are already
1966 * removed for resizing to occur.
1968 * Returns the max number of subordinate bus discovered.
1970 unsigned int __ref pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
1972 unsigned int max;
1973 struct pci_bus *bus = bridge->subordinate;
1975 max = pci_scan_child_bus(bus);
1977 pci_assign_unassigned_bridge_resources(bridge);
1979 pci_bus_add_devices(bus);
1981 return max;
1985 * pci_rescan_bus - scan a PCI bus for devices.
1986 * @bus: PCI bus to scan
1988 * Scan a PCI bus and child buses for new devices, adds them,
1989 * and enables them.
1991 * Returns the max number of subordinate bus discovered.
1993 unsigned int __ref pci_rescan_bus(struct pci_bus *bus)
1995 unsigned int max;
1997 max = pci_scan_child_bus(bus);
1998 pci_assign_unassigned_bus_resources(bus);
1999 pci_bus_add_devices(bus);
2001 return max;
2003 EXPORT_SYMBOL_GPL(pci_rescan_bus);
2005 EXPORT_SYMBOL(pci_add_new_bus);
2006 EXPORT_SYMBOL(pci_scan_slot);
2007 EXPORT_SYMBOL(pci_scan_bridge);
2008 EXPORT_SYMBOL_GPL(pci_scan_child_bus);
2011 * pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal
2012 * routines should always be executed under this mutex.
2014 static DEFINE_MUTEX(pci_rescan_remove_lock);
2016 void pci_lock_rescan_remove(void)
2018 mutex_lock(&pci_rescan_remove_lock);
2020 EXPORT_SYMBOL_GPL(pci_lock_rescan_remove);
2022 void pci_unlock_rescan_remove(void)
2024 mutex_unlock(&pci_rescan_remove_lock);
2026 EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove);
2028 static int __init pci_sort_bf_cmp(const struct device *d_a, const struct device *d_b)
2030 const struct pci_dev *a = to_pci_dev(d_a);
2031 const struct pci_dev *b = to_pci_dev(d_b);
2033 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
2034 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
2036 if (a->bus->number < b->bus->number) return -1;
2037 else if (a->bus->number > b->bus->number) return 1;
2039 if (a->devfn < b->devfn) return -1;
2040 else if (a->devfn > b->devfn) return 1;
2042 return 0;
2045 void __init pci_sort_breadthfirst(void)
2047 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);