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 static 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_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 */
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 */
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)
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
202 if (!sz || sz == 0xffffffff)
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.
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;
219 l &= PCI_BASE_ADDRESS_MEM_MASK;
220 mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
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) {
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);
246 if ((sizeof(resource_size_t) < 8) && (sz64 > 0x100000000ULL)) {
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);
260 region.end = l64 + sz64;
263 sz = pci_size(l, sz, mask);
272 pcibios_bus_to_resource(dev->bus, res, ®ion);
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",
289 res->flags |= IORESOURCE_UNSET;
290 res->end -= res->start;
300 if (!dev->mmio_always_on &&
301 (orig_cmd & PCI_COMMAND_DECODE_ENABLE))
302 pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
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);
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);
364 res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
366 region.end = limit + io_granularity - 1;
367 pcibios_bus_to_resource(dev->bus, res, ®ion);
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;
386 res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
388 region.end = limit + 0xfffff;
389 pcibios_bus_to_resource(dev->bus, res, ®ion);
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;
399 dma_addr_t base, limit;
400 struct pci_bus_region region;
401 struct resource *res;
403 res = child->resource[2];
404 pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
405 pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
406 base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
407 limit64 = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
409 if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
410 u32 mem_base_hi, mem_limit_hi;
412 pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
413 pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
416 * Some bridges set the base > limit by default, and some
417 * (broken) BIOSes do not initialize them. If we find
418 * this, just assume they are not being used.
420 if (mem_base_hi <= mem_limit_hi) {
421 base64 |= (u64) mem_base_hi << 32;
422 limit64 |= (u64) mem_limit_hi << 32;
426 base = (dma_addr_t) base64;
427 limit = (dma_addr_t) limit64;
429 if (base != base64) {
430 dev_err(&dev->dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
431 (unsigned long long) base64);
436 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
437 IORESOURCE_MEM | IORESOURCE_PREFETCH;
438 if (res->flags & PCI_PREF_RANGE_TYPE_64)
439 res->flags |= IORESOURCE_MEM_64;
441 region.end = limit + 0xfffff;
442 pcibios_bus_to_resource(dev->bus, res, ®ion);
443 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
447 void pci_read_bridge_bases(struct pci_bus *child)
449 struct pci_dev *dev = child->self;
450 struct resource *res;
453 if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
456 dev_info(&dev->dev, "PCI bridge to %pR%s\n",
458 dev->transparent ? " (subtractive decode)" : "");
460 pci_bus_remove_resources(child);
461 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
462 child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
464 pci_read_bridge_io(child);
465 pci_read_bridge_mmio(child);
466 pci_read_bridge_mmio_pref(child);
468 if (dev->transparent) {
469 pci_bus_for_each_resource(child->parent, res, i) {
471 pci_bus_add_resource(child, res,
472 PCI_SUBTRACTIVE_DECODE);
473 dev_printk(KERN_DEBUG, &dev->dev,
474 " bridge window %pR (subtractive decode)\n",
481 static struct pci_bus *pci_alloc_bus(void)
485 b = kzalloc(sizeof(*b), GFP_KERNEL);
489 INIT_LIST_HEAD(&b->node);
490 INIT_LIST_HEAD(&b->children);
491 INIT_LIST_HEAD(&b->devices);
492 INIT_LIST_HEAD(&b->slots);
493 INIT_LIST_HEAD(&b->resources);
494 b->max_bus_speed = PCI_SPEED_UNKNOWN;
495 b->cur_bus_speed = PCI_SPEED_UNKNOWN;
499 static void pci_release_host_bridge_dev(struct device *dev)
501 struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
503 if (bridge->release_fn)
504 bridge->release_fn(bridge);
506 pci_free_resource_list(&bridge->windows);
511 static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b)
513 struct pci_host_bridge *bridge;
515 bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
519 INIT_LIST_HEAD(&bridge->windows);
524 static const unsigned char pcix_bus_speed[] = {
525 PCI_SPEED_UNKNOWN, /* 0 */
526 PCI_SPEED_66MHz_PCIX, /* 1 */
527 PCI_SPEED_100MHz_PCIX, /* 2 */
528 PCI_SPEED_133MHz_PCIX, /* 3 */
529 PCI_SPEED_UNKNOWN, /* 4 */
530 PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
531 PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
532 PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
533 PCI_SPEED_UNKNOWN, /* 8 */
534 PCI_SPEED_66MHz_PCIX_266, /* 9 */
535 PCI_SPEED_100MHz_PCIX_266, /* A */
536 PCI_SPEED_133MHz_PCIX_266, /* B */
537 PCI_SPEED_UNKNOWN, /* C */
538 PCI_SPEED_66MHz_PCIX_533, /* D */
539 PCI_SPEED_100MHz_PCIX_533, /* E */
540 PCI_SPEED_133MHz_PCIX_533 /* F */
543 const unsigned char pcie_link_speed[] = {
544 PCI_SPEED_UNKNOWN, /* 0 */
545 PCIE_SPEED_2_5GT, /* 1 */
546 PCIE_SPEED_5_0GT, /* 2 */
547 PCIE_SPEED_8_0GT, /* 3 */
548 PCI_SPEED_UNKNOWN, /* 4 */
549 PCI_SPEED_UNKNOWN, /* 5 */
550 PCI_SPEED_UNKNOWN, /* 6 */
551 PCI_SPEED_UNKNOWN, /* 7 */
552 PCI_SPEED_UNKNOWN, /* 8 */
553 PCI_SPEED_UNKNOWN, /* 9 */
554 PCI_SPEED_UNKNOWN, /* A */
555 PCI_SPEED_UNKNOWN, /* B */
556 PCI_SPEED_UNKNOWN, /* C */
557 PCI_SPEED_UNKNOWN, /* D */
558 PCI_SPEED_UNKNOWN, /* E */
559 PCI_SPEED_UNKNOWN /* F */
562 void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
564 bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS];
566 EXPORT_SYMBOL_GPL(pcie_update_link_speed);
568 static unsigned char agp_speeds[] = {
576 static enum pci_bus_speed agp_speed(int agp3, int agpstat)
582 else if (agpstat & 2)
584 else if (agpstat & 1)
596 return agp_speeds[index];
600 static void pci_set_bus_speed(struct pci_bus *bus)
602 struct pci_dev *bridge = bus->self;
605 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
607 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
611 pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
612 bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
614 pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
615 bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
618 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
621 enum pci_bus_speed max;
623 pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
626 if (status & PCI_X_SSTATUS_533MHZ) {
627 max = PCI_SPEED_133MHz_PCIX_533;
628 } else if (status & PCI_X_SSTATUS_266MHZ) {
629 max = PCI_SPEED_133MHz_PCIX_266;
630 } else if (status & PCI_X_SSTATUS_133MHZ) {
631 if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2) {
632 max = PCI_SPEED_133MHz_PCIX_ECC;
634 max = PCI_SPEED_133MHz_PCIX;
637 max = PCI_SPEED_66MHz_PCIX;
640 bus->max_bus_speed = max;
641 bus->cur_bus_speed = pcix_bus_speed[
642 (status & PCI_X_SSTATUS_FREQ) >> 6];
647 if (pci_is_pcie(bridge)) {
651 pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
652 bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
654 pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
655 pcie_update_link_speed(bus, linksta);
660 static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
661 struct pci_dev *bridge, int busnr)
663 struct pci_bus *child;
668 * Allocate a new bus, and inherit stuff from the parent..
670 child = pci_alloc_bus();
674 child->parent = parent;
675 child->ops = parent->ops;
676 child->msi = parent->msi;
677 child->sysdata = parent->sysdata;
678 child->bus_flags = parent->bus_flags;
680 /* initialize some portions of the bus device, but don't register it
681 * now as the parent is not properly set up yet.
683 child->dev.class = &pcibus_class;
684 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
687 * Set up the primary, secondary and subordinate
690 child->number = child->busn_res.start = busnr;
691 child->primary = parent->busn_res.start;
692 child->busn_res.end = 0xff;
695 child->dev.parent = parent->bridge;
699 child->self = bridge;
700 child->bridge = get_device(&bridge->dev);
701 child->dev.parent = child->bridge;
702 pci_set_bus_of_node(child);
703 pci_set_bus_speed(child);
705 /* Set up default resource pointers and names.. */
706 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
707 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
708 child->resource[i]->name = child->name;
710 bridge->subordinate = child;
713 ret = device_register(&child->dev);
716 pcibios_add_bus(child);
718 /* Create legacy_io and legacy_mem files for this bus */
719 pci_create_legacy_files(child);
724 struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr)
726 struct pci_bus *child;
728 child = pci_alloc_child_bus(parent, dev, busnr);
730 down_write(&pci_bus_sem);
731 list_add_tail(&child->node, &parent->children);
732 up_write(&pci_bus_sem);
737 static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
739 struct pci_bus *parent = child->parent;
741 /* Attempts to fix that up are really dangerous unless
742 we're going to re-assign all bus numbers. */
743 if (!pcibios_assign_all_busses())
746 while (parent->parent && parent->busn_res.end < max) {
747 parent->busn_res.end = max;
748 pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);
749 parent = parent->parent;
754 * If it's a bridge, configure it and scan the bus behind it.
755 * For CardBus bridges, we don't scan behind as the devices will
756 * be handled by the bridge driver itself.
758 * We need to process bridges in two passes -- first we scan those
759 * already configured by the BIOS and after we are done with all of
760 * them, we proceed to assigning numbers to the remaining buses in
761 * order to avoid overlaps between old and new bus numbers.
763 int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
765 struct pci_bus *child;
766 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
769 u8 primary, secondary, subordinate;
772 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
773 primary = buses & 0xFF;
774 secondary = (buses >> 8) & 0xFF;
775 subordinate = (buses >> 16) & 0xFF;
777 dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
778 secondary, subordinate, pass);
780 if (!primary && (primary != bus->number) && secondary && subordinate) {
781 dev_warn(&dev->dev, "Primary bus is hard wired to 0\n");
782 primary = bus->number;
785 /* Check if setup is sensible at all */
787 (primary != bus->number || secondary <= bus->number ||
788 secondary > subordinate)) {
789 dev_info(&dev->dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
790 secondary, subordinate);
794 /* Disable MasterAbortMode during probing to avoid reporting
795 of bus errors (in some architectures) */
796 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
797 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
798 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
800 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
801 !is_cardbus && !broken) {
804 * Bus already configured by firmware, process it in the first
805 * pass and just note the configuration.
811 * If we already got to this bus through a different bridge,
812 * don't re-add it. This can happen with the i450NX chipset.
814 * However, we continue to descend down the hierarchy and
815 * scan remaining child buses.
817 child = pci_find_bus(pci_domain_nr(bus), secondary);
819 child = pci_add_new_bus(bus, dev, secondary);
822 child->primary = primary;
823 pci_bus_insert_busn_res(child, secondary, subordinate);
824 child->bridge_ctl = bctl;
827 cmax = pci_scan_child_bus(child);
830 if (child->busn_res.end > max)
831 max = child->busn_res.end;
834 * We need to assign a number to this bus which we always
835 * do in the second pass.
838 if (pcibios_assign_all_busses() || broken)
839 /* Temporarily disable forwarding of the
840 configuration cycles on all bridges in
841 this bus segment to avoid possible
842 conflicts in the second pass between two
843 bridges programmed with overlapping
845 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
851 pci_write_config_word(dev, PCI_STATUS, 0xffff);
853 /* Prevent assigning a bus number that already exists.
854 * This can happen when a bridge is hot-plugged, so in
855 * this case we only re-scan this bus. */
856 child = pci_find_bus(pci_domain_nr(bus), max+1);
858 child = pci_add_new_bus(bus, dev, ++max);
861 pci_bus_insert_busn_res(child, max, 0xff);
863 buses = (buses & 0xff000000)
864 | ((unsigned int)(child->primary) << 0)
865 | ((unsigned int)(child->busn_res.start) << 8)
866 | ((unsigned int)(child->busn_res.end) << 16);
869 * yenta.c forces a secondary latency timer of 176.
870 * Copy that behaviour here.
873 buses &= ~0xff000000;
874 buses |= CARDBUS_LATENCY_TIMER << 24;
878 * We need to blast all three values with a single write.
880 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
883 child->bridge_ctl = bctl;
885 * Adjust subordinate busnr in parent buses.
886 * We do this before scanning for children because
887 * some devices may not be detected if the bios
890 pci_fixup_parent_subordinate_busnr(child, max);
891 /* Now we can scan all subordinate buses... */
892 max = pci_scan_child_bus(child);
894 * now fix it up again since we have found
895 * the real value of max.
897 pci_fixup_parent_subordinate_busnr(child, max);
900 * For CardBus bridges, we leave 4 bus numbers
901 * as cards with a PCI-to-PCI bridge can be
904 for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
905 struct pci_bus *parent = bus;
906 if (pci_find_bus(pci_domain_nr(bus),
909 while (parent->parent) {
910 if ((!pcibios_assign_all_busses()) &&
911 (parent->busn_res.end > max) &&
912 (parent->busn_res.end <= max+i)) {
915 parent = parent->parent;
919 * Often, there are two cardbus bridges
920 * -- try to leave one valid bus number
928 pci_fixup_parent_subordinate_busnr(child, max);
931 * Set the subordinate bus number to its real value.
933 pci_bus_update_busn_res_end(child, max);
934 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
938 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
939 pci_domain_nr(bus), child->number);
941 /* Has only triggered on CardBus, fixup is in yenta_socket */
942 while (bus->parent) {
943 if ((child->busn_res.end > bus->busn_res.end) ||
944 (child->number > bus->busn_res.end) ||
945 (child->number < bus->number) ||
946 (child->busn_res.end < bus->number)) {
947 dev_info(&child->dev, "%pR %s "
948 "hidden behind%s bridge %s %pR\n",
950 (bus->number > child->busn_res.end &&
951 bus->busn_res.end < child->number) ?
952 "wholly" : "partially",
953 bus->self->transparent ? " transparent" : "",
961 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
967 * Read interrupt line and base address registers.
968 * The architecture-dependent code can tweak these, of course.
970 static void pci_read_irq(struct pci_dev *dev)
974 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
977 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
981 void set_pcie_port_type(struct pci_dev *pdev)
986 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
989 pdev->pcie_cap = pos;
990 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
991 pdev->pcie_flags_reg = reg16;
992 pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16);
993 pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
996 void set_pcie_hotplug_bridge(struct pci_dev *pdev)
1000 pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32);
1001 if (reg32 & PCI_EXP_SLTCAP_HPC)
1002 pdev->is_hotplug_bridge = 1;
1007 * pci_cfg_space_size - get the configuration space size of the PCI device.
1010 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1011 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1012 * access it. Maybe we don't have a way to generate extended config space
1013 * accesses, or the device is behind a reverse Express bridge. So we try
1014 * reading the dword at 0x100 which must either be 0 or a valid extended
1015 * capability header.
1017 static int pci_cfg_space_size_ext(struct pci_dev *dev)
1020 int pos = PCI_CFG_SPACE_SIZE;
1022 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1024 if (status == 0xffffffff)
1027 return PCI_CFG_SPACE_EXP_SIZE;
1030 return PCI_CFG_SPACE_SIZE;
1033 int pci_cfg_space_size(struct pci_dev *dev)
1039 class = dev->class >> 8;
1040 if (class == PCI_CLASS_BRIDGE_HOST)
1041 return pci_cfg_space_size_ext(dev);
1043 if (!pci_is_pcie(dev)) {
1044 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1048 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1049 if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
1053 return pci_cfg_space_size_ext(dev);
1056 return PCI_CFG_SPACE_SIZE;
1059 #define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
1062 * pci_setup_device - fill in class and map information of a device
1063 * @dev: the device structure to fill
1065 * Initialize the device structure with information about the device's
1066 * vendor,class,memory and IO-space addresses,IRQ lines etc.
1067 * Called at initialisation of the PCI subsystem and by CardBus services.
1068 * Returns 0 on success and negative if unknown type of device (not normal,
1069 * bridge or CardBus).
1071 int pci_setup_device(struct pci_dev *dev)
1075 struct pci_slot *slot;
1077 struct pci_bus_region region;
1078 struct resource *res;
1080 if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
1083 dev->sysdata = dev->bus->sysdata;
1084 dev->dev.parent = dev->bus->bridge;
1085 dev->dev.bus = &pci_bus_type;
1086 dev->hdr_type = hdr_type & 0x7f;
1087 dev->multifunction = !!(hdr_type & 0x80);
1088 dev->error_state = pci_channel_io_normal;
1089 set_pcie_port_type(dev);
1091 list_for_each_entry(slot, &dev->bus->slots, list)
1092 if (PCI_SLOT(dev->devfn) == slot->number)
1095 /* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
1096 set this higher, assuming the system even supports it. */
1097 dev->dma_mask = 0xffffffff;
1099 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
1100 dev->bus->number, PCI_SLOT(dev->devfn),
1101 PCI_FUNC(dev->devfn));
1103 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
1104 dev->revision = class & 0xff;
1105 dev->class = class >> 8; /* upper 3 bytes */
1107 dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %02x class %#08x\n",
1108 dev->vendor, dev->device, dev->hdr_type, dev->class);
1110 /* need to have dev->class ready */
1111 dev->cfg_size = pci_cfg_space_size(dev);
1113 /* "Unknown power state" */
1114 dev->current_state = PCI_UNKNOWN;
1116 /* Early fixups, before probing the BARs */
1117 pci_fixup_device(pci_fixup_early, dev);
1118 /* device class may be changed after fixup */
1119 class = dev->class >> 8;
1121 switch (dev->hdr_type) { /* header type */
1122 case PCI_HEADER_TYPE_NORMAL: /* standard header */
1123 if (class == PCI_CLASS_BRIDGE_PCI)
1126 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1127 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1128 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
1131 * Do the ugly legacy mode stuff here rather than broken chip
1132 * quirk code. Legacy mode ATA controllers have fixed
1133 * addresses. These are not always echoed in BAR0-3, and
1134 * BAR0-3 in a few cases contain junk!
1136 if (class == PCI_CLASS_STORAGE_IDE) {
1138 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1139 if ((progif & 1) == 0) {
1140 region.start = 0x1F0;
1142 res = &dev->resource[0];
1143 res->flags = LEGACY_IO_RESOURCE;
1144 pcibios_bus_to_resource(dev->bus, res, ®ion);
1145 region.start = 0x3F6;
1147 res = &dev->resource[1];
1148 res->flags = LEGACY_IO_RESOURCE;
1149 pcibios_bus_to_resource(dev->bus, res, ®ion);
1151 if ((progif & 4) == 0) {
1152 region.start = 0x170;
1154 res = &dev->resource[2];
1155 res->flags = LEGACY_IO_RESOURCE;
1156 pcibios_bus_to_resource(dev->bus, res, ®ion);
1157 region.start = 0x376;
1159 res = &dev->resource[3];
1160 res->flags = LEGACY_IO_RESOURCE;
1161 pcibios_bus_to_resource(dev->bus, res, ®ion);
1166 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1167 if (class != PCI_CLASS_BRIDGE_PCI)
1169 /* The PCI-to-PCI bridge spec requires that subtractive
1170 decoding (i.e. transparent) bridge must have programming
1171 interface code of 0x01. */
1173 dev->transparent = ((dev->class & 0xff) == 1);
1174 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1175 set_pcie_hotplug_bridge(dev);
1176 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1178 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1179 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1183 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1184 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1187 pci_read_bases(dev, 1, 0);
1188 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1189 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1192 default: /* unknown header */
1193 dev_err(&dev->dev, "unknown header type %02x, "
1194 "ignoring device\n", dev->hdr_type);
1198 dev_err(&dev->dev, "ignoring class %#08x (doesn't match header "
1199 "type %02x)\n", dev->class, dev->hdr_type);
1200 dev->class = PCI_CLASS_NOT_DEFINED;
1203 /* We found a fine healthy device, go go go... */
1207 static void pci_release_capabilities(struct pci_dev *dev)
1209 pci_vpd_release(dev);
1210 pci_iov_release(dev);
1211 pci_free_cap_save_buffers(dev);
1215 * pci_release_dev - free a pci device structure when all users of it are finished.
1216 * @dev: device that's been disconnected
1218 * Will be called only by the device core when all users of this pci device are
1221 static void pci_release_dev(struct device *dev)
1223 struct pci_dev *pci_dev;
1225 pci_dev = to_pci_dev(dev);
1226 pci_release_capabilities(pci_dev);
1227 pci_release_of_node(pci_dev);
1228 pcibios_release_device(pci_dev);
1229 pci_bus_put(pci_dev->bus);
1233 struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
1235 struct pci_dev *dev;
1237 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
1241 INIT_LIST_HEAD(&dev->bus_list);
1242 dev->dev.type = &pci_dev_type;
1243 dev->bus = pci_bus_get(bus);
1247 EXPORT_SYMBOL(pci_alloc_dev);
1249 bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
1254 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1257 /* some broken boards return 0 or ~0 if a slot is empty: */
1258 if (*l == 0xffffffff || *l == 0x00000000 ||
1259 *l == 0x0000ffff || *l == 0xffff0000)
1262 /* Configuration request Retry Status */
1263 while (*l == 0xffff0001) {
1269 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1271 /* Card hasn't responded in 60 seconds? Must be stuck. */
1272 if (delay > crs_timeout) {
1273 printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not "
1274 "responding\n", pci_domain_nr(bus),
1275 bus->number, PCI_SLOT(devfn),
1283 EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
1286 * Read the config data for a PCI device, sanity-check it
1287 * and fill in the dev structure...
1289 static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
1291 struct pci_dev *dev;
1294 if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
1297 dev = pci_alloc_dev(bus);
1302 dev->vendor = l & 0xffff;
1303 dev->device = (l >> 16) & 0xffff;
1305 pci_set_of_node(dev);
1307 if (pci_setup_device(dev)) {
1308 pci_bus_put(dev->bus);
1316 static void pci_init_capabilities(struct pci_dev *dev)
1318 /* MSI/MSI-X list */
1319 pci_msi_init_pci_dev(dev);
1321 /* Buffers for saving PCIe and PCI-X capabilities */
1322 pci_allocate_cap_save_buffers(dev);
1324 /* Power Management */
1327 /* Vital Product Data */
1328 pci_vpd_pci22_init(dev);
1330 /* Alternative Routing-ID Forwarding */
1331 pci_configure_ari(dev);
1333 /* Single Root I/O Virtualization */
1336 /* Enable ACS P2P upstream forwarding */
1337 pci_enable_acs(dev);
1340 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
1344 device_initialize(&dev->dev);
1345 dev->dev.release = pci_release_dev;
1347 set_dev_node(&dev->dev, pcibus_to_node(bus));
1348 dev->dev.dma_mask = &dev->dma_mask;
1349 dev->dev.dma_parms = &dev->dma_parms;
1350 dev->dev.coherent_dma_mask = 0xffffffffull;
1352 pci_set_dma_max_seg_size(dev, 65536);
1353 pci_set_dma_seg_boundary(dev, 0xffffffff);
1355 /* Fix up broken headers */
1356 pci_fixup_device(pci_fixup_header, dev);
1358 /* moved out from quirk header fixup code */
1359 pci_reassigndev_resource_alignment(dev);
1361 /* Clear the state_saved flag. */
1362 dev->state_saved = false;
1364 /* Initialize various capabilities */
1365 pci_init_capabilities(dev);
1368 * Add the device to our list of discovered devices
1369 * and the bus list for fixup functions, etc.
1371 down_write(&pci_bus_sem);
1372 list_add_tail(&dev->bus_list, &bus->devices);
1373 up_write(&pci_bus_sem);
1375 ret = pcibios_add_device(dev);
1378 /* Notifier could use PCI capabilities */
1379 dev->match_driver = false;
1380 ret = device_add(&dev->dev);
1384 struct pci_dev *__ref pci_scan_single_device(struct pci_bus *bus, int devfn)
1386 struct pci_dev *dev;
1388 dev = pci_get_slot(bus, devfn);
1394 dev = pci_scan_device(bus, devfn);
1398 pci_device_add(dev, bus);
1402 EXPORT_SYMBOL(pci_scan_single_device);
1404 static unsigned next_fn(struct pci_bus *bus, struct pci_dev *dev, unsigned fn)
1410 if (pci_ari_enabled(bus)) {
1413 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1417 pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap);
1418 next_fn = PCI_ARI_CAP_NFN(cap);
1420 return 0; /* protect against malformed list */
1425 /* dev may be NULL for non-contiguous multifunction devices */
1426 if (!dev || dev->multifunction)
1427 return (fn + 1) % 8;
1432 static int only_one_child(struct pci_bus *bus)
1434 struct pci_dev *parent = bus->self;
1436 if (!parent || !pci_is_pcie(parent))
1438 if (pci_pcie_type(parent) == PCI_EXP_TYPE_ROOT_PORT)
1440 if (pci_pcie_type(parent) == PCI_EXP_TYPE_DOWNSTREAM &&
1441 !pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
1447 * pci_scan_slot - scan a PCI slot on a bus for devices.
1448 * @bus: PCI bus to scan
1449 * @devfn: slot number to scan (must have zero function.)
1451 * Scan a PCI slot on the specified PCI bus for devices, adding
1452 * discovered devices to the @bus->devices list. New devices
1453 * will not have is_added set.
1455 * Returns the number of new devices found.
1457 int pci_scan_slot(struct pci_bus *bus, int devfn)
1459 unsigned fn, nr = 0;
1460 struct pci_dev *dev;
1462 if (only_one_child(bus) && (devfn > 0))
1463 return 0; /* Already scanned the entire slot */
1465 dev = pci_scan_single_device(bus, devfn);
1471 for (fn = next_fn(bus, dev, 0); fn > 0; fn = next_fn(bus, dev, fn)) {
1472 dev = pci_scan_single_device(bus, devfn + fn);
1476 dev->multifunction = 1;
1480 /* only one slot has pcie device */
1481 if (bus->self && nr)
1482 pcie_aspm_init_link_state(bus->self);
1487 static int pcie_find_smpss(struct pci_dev *dev, void *data)
1491 if (!pci_is_pcie(dev))
1495 * We don't have a way to change MPS settings on devices that have
1496 * drivers attached. A hot-added device might support only the minimum
1497 * MPS setting (MPS=128). Therefore, if the fabric contains a bridge
1498 * where devices may be hot-added, we limit the fabric MPS to 128 so
1499 * hot-added devices will work correctly.
1501 * However, if we hot-add a device to a slot directly below a Root
1502 * Port, it's impossible for there to be other existing devices below
1503 * the port. We don't limit the MPS in this case because we can
1504 * reconfigure MPS on both the Root Port and the hot-added device,
1505 * and there are no other devices involved.
1507 * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
1509 if (dev->is_hotplug_bridge &&
1510 pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
1513 if (*smpss > dev->pcie_mpss)
1514 *smpss = dev->pcie_mpss;
1519 static void pcie_write_mps(struct pci_dev *dev, int mps)
1523 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
1524 mps = 128 << dev->pcie_mpss;
1526 if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
1528 /* For "Performance", the assumption is made that
1529 * downstream communication will never be larger than
1530 * the MRRS. So, the MPS only needs to be configured
1531 * for the upstream communication. This being the case,
1532 * walk from the top down and set the MPS of the child
1533 * to that of the parent bus.
1535 * Configure the device MPS with the smaller of the
1536 * device MPSS or the bridge MPS (which is assumed to be
1537 * properly configured at this point to the largest
1538 * allowable MPS based on its parent bus).
1540 mps = min(mps, pcie_get_mps(dev->bus->self));
1543 rc = pcie_set_mps(dev, mps);
1545 dev_err(&dev->dev, "Failed attempting to set the MPS\n");
1548 static void pcie_write_mrrs(struct pci_dev *dev)
1552 /* In the "safe" case, do not configure the MRRS. There appear to be
1553 * issues with setting MRRS to 0 on a number of devices.
1555 if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
1558 /* For Max performance, the MRRS must be set to the largest supported
1559 * value. However, it cannot be configured larger than the MPS the
1560 * device or the bus can support. This should already be properly
1561 * configured by a prior call to pcie_write_mps.
1563 mrrs = pcie_get_mps(dev);
1565 /* MRRS is a R/W register. Invalid values can be written, but a
1566 * subsequent read will verify if the value is acceptable or not.
1567 * If the MRRS value provided is not acceptable (e.g., too large),
1568 * shrink the value until it is acceptable to the HW.
1570 while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
1571 rc = pcie_set_readrq(dev, mrrs);
1575 dev_warn(&dev->dev, "Failed attempting to set the MRRS\n");
1580 dev_err(&dev->dev, "MRRS was unable to be configured with a "
1581 "safe value. If problems are experienced, try running "
1582 "with pci=pcie_bus_safe.\n");
1585 static void pcie_bus_detect_mps(struct pci_dev *dev)
1587 struct pci_dev *bridge = dev->bus->self;
1593 mps = pcie_get_mps(dev);
1594 p_mps = pcie_get_mps(bridge);
1597 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",
1598 mps, pci_name(bridge), p_mps);
1601 static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
1605 if (!pci_is_pcie(dev))
1608 if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
1609 pcie_bus_detect_mps(dev);
1613 mps = 128 << *(u8 *)data;
1614 orig_mps = pcie_get_mps(dev);
1616 pcie_write_mps(dev, mps);
1617 pcie_write_mrrs(dev);
1619 dev_info(&dev->dev, "Max Payload Size set to %4d/%4d (was %4d), "
1620 "Max Read Rq %4d\n", pcie_get_mps(dev), 128 << dev->pcie_mpss,
1621 orig_mps, pcie_get_readrq(dev));
1626 /* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down,
1627 * parents then children fashion. If this changes, then this code will not
1630 void pcie_bus_configure_settings(struct pci_bus *bus)
1637 if (!pci_is_pcie(bus->self))
1640 /* FIXME - Peer to peer DMA is possible, though the endpoint would need
1641 * to be aware of the MPS of the destination. To work around this,
1642 * simply force the MPS of the entire system to the smallest possible.
1644 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
1647 if (pcie_bus_config == PCIE_BUS_SAFE) {
1648 smpss = bus->self->pcie_mpss;
1650 pcie_find_smpss(bus->self, &smpss);
1651 pci_walk_bus(bus, pcie_find_smpss, &smpss);
1654 pcie_bus_configure_set(bus->self, &smpss);
1655 pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
1657 EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
1659 unsigned int pci_scan_child_bus(struct pci_bus *bus)
1661 unsigned int devfn, pass, max = bus->busn_res.start;
1662 struct pci_dev *dev;
1664 dev_dbg(&bus->dev, "scanning bus\n");
1666 /* Go find them, Rover! */
1667 for (devfn = 0; devfn < 0x100; devfn += 8)
1668 pci_scan_slot(bus, devfn);
1670 /* Reserve buses for SR-IOV capability. */
1671 max += pci_iov_bus_range(bus);
1674 * After performing arch-dependent fixup of the bus, look behind
1675 * all PCI-to-PCI bridges on this bus.
1677 if (!bus->is_added) {
1678 dev_dbg(&bus->dev, "fixups for bus\n");
1679 pcibios_fixup_bus(bus);
1683 for (pass=0; pass < 2; pass++)
1684 list_for_each_entry(dev, &bus->devices, bus_list) {
1685 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
1686 dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
1687 max = pci_scan_bridge(bus, dev, max, pass);
1691 * We've scanned the bus and so we know all about what's on
1692 * the other side of any bridges that may be on this bus plus
1695 * Return how far we've got finding sub-buses.
1697 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
1702 * pcibios_root_bridge_prepare - Platform-specific host bridge setup.
1703 * @bridge: Host bridge to set up.
1705 * Default empty implementation. Replace with an architecture-specific setup
1706 * routine, if necessary.
1708 int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
1713 void __weak pcibios_add_bus(struct pci_bus *bus)
1717 void __weak pcibios_remove_bus(struct pci_bus *bus)
1721 struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
1722 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1725 struct pci_host_bridge *bridge;
1726 struct pci_bus *b, *b2;
1727 struct pci_host_bridge_window *window, *n;
1728 struct resource *res;
1729 resource_size_t offset;
1733 b = pci_alloc_bus();
1737 b->sysdata = sysdata;
1739 b->number = b->busn_res.start = bus;
1740 b2 = pci_find_bus(pci_domain_nr(b), bus);
1742 /* If we already got to this bus through a different bridge, ignore it */
1743 dev_dbg(&b2->dev, "bus already known\n");
1747 bridge = pci_alloc_host_bridge(b);
1751 bridge->dev.parent = parent;
1752 bridge->dev.release = pci_release_host_bridge_dev;
1753 dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
1754 error = pcibios_root_bridge_prepare(bridge);
1760 error = device_register(&bridge->dev);
1762 put_device(&bridge->dev);
1765 b->bridge = get_device(&bridge->dev);
1766 device_enable_async_suspend(b->bridge);
1767 pci_set_bus_of_node(b);
1770 set_dev_node(b->bridge, pcibus_to_node(b));
1772 b->dev.class = &pcibus_class;
1773 b->dev.parent = b->bridge;
1774 dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
1775 error = device_register(&b->dev);
1777 goto class_dev_reg_err;
1781 /* Create legacy_io and legacy_mem files for this bus */
1782 pci_create_legacy_files(b);
1785 dev_info(parent, "PCI host bridge to bus %s\n", dev_name(&b->dev));
1787 printk(KERN_INFO "PCI host bridge to bus %s\n", dev_name(&b->dev));
1789 /* Add initial resources to the bus */
1790 list_for_each_entry_safe(window, n, resources, list) {
1791 list_move_tail(&window->list, &bridge->windows);
1793 offset = window->offset;
1794 if (res->flags & IORESOURCE_BUS)
1795 pci_bus_insert_busn_res(b, bus, res->end);
1797 pci_bus_add_resource(b, res, 0);
1799 if (resource_type(res) == IORESOURCE_IO)
1800 fmt = " (bus address [%#06llx-%#06llx])";
1802 fmt = " (bus address [%#010llx-%#010llx])";
1803 snprintf(bus_addr, sizeof(bus_addr), fmt,
1804 (unsigned long long) (res->start - offset),
1805 (unsigned long long) (res->end - offset));
1808 dev_info(&b->dev, "root bus resource %pR%s\n", res, bus_addr);
1811 down_write(&pci_bus_sem);
1812 list_add_tail(&b->node, &pci_root_buses);
1813 up_write(&pci_bus_sem);
1818 put_device(&bridge->dev);
1819 device_unregister(&bridge->dev);
1825 int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
1827 struct resource *res = &b->busn_res;
1828 struct resource *parent_res, *conflict;
1832 res->flags = IORESOURCE_BUS;
1834 if (!pci_is_root_bus(b))
1835 parent_res = &b->parent->busn_res;
1837 parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
1838 res->flags |= IORESOURCE_PCI_FIXED;
1841 conflict = insert_resource_conflict(parent_res, res);
1844 dev_printk(KERN_DEBUG, &b->dev,
1845 "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
1846 res, pci_is_root_bus(b) ? "domain " : "",
1847 parent_res, conflict->name, conflict);
1849 return conflict == NULL;
1852 int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
1854 struct resource *res = &b->busn_res;
1855 struct resource old_res = *res;
1856 resource_size_t size;
1859 if (res->start > bus_max)
1862 size = bus_max - res->start + 1;
1863 ret = adjust_resource(res, res->start, size);
1864 dev_printk(KERN_DEBUG, &b->dev,
1865 "busn_res: %pR end %s updated to %02x\n",
1866 &old_res, ret ? "can not be" : "is", bus_max);
1868 if (!ret && !res->parent)
1869 pci_bus_insert_busn_res(b, res->start, res->end);
1874 void pci_bus_release_busn_res(struct pci_bus *b)
1876 struct resource *res = &b->busn_res;
1879 if (!res->flags || !res->parent)
1882 ret = release_resource(res);
1883 dev_printk(KERN_DEBUG, &b->dev,
1884 "busn_res: %pR %s released\n",
1885 res, ret ? "can not be" : "is");
1888 struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
1889 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1891 struct pci_host_bridge_window *window;
1896 list_for_each_entry(window, resources, list)
1897 if (window->res->flags & IORESOURCE_BUS) {
1902 b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
1908 "No busn resource found for root bus, will use [bus %02x-ff]\n",
1910 pci_bus_insert_busn_res(b, bus, 255);
1913 max = pci_scan_child_bus(b);
1916 pci_bus_update_busn_res_end(b, max);
1918 pci_bus_add_devices(b);
1921 EXPORT_SYMBOL(pci_scan_root_bus);
1923 /* Deprecated; use pci_scan_root_bus() instead */
1924 struct pci_bus *pci_scan_bus_parented(struct device *parent,
1925 int bus, struct pci_ops *ops, void *sysdata)
1927 LIST_HEAD(resources);
1930 pci_add_resource(&resources, &ioport_resource);
1931 pci_add_resource(&resources, &iomem_resource);
1932 pci_add_resource(&resources, &busn_resource);
1933 b = pci_create_root_bus(parent, bus, ops, sysdata, &resources);
1935 pci_scan_child_bus(b);
1937 pci_free_resource_list(&resources);
1940 EXPORT_SYMBOL(pci_scan_bus_parented);
1942 struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
1945 LIST_HEAD(resources);
1948 pci_add_resource(&resources, &ioport_resource);
1949 pci_add_resource(&resources, &iomem_resource);
1950 pci_add_resource(&resources, &busn_resource);
1951 b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
1953 pci_scan_child_bus(b);
1954 pci_bus_add_devices(b);
1956 pci_free_resource_list(&resources);
1960 EXPORT_SYMBOL(pci_scan_bus);
1963 * pci_rescan_bus_bridge_resize - scan a PCI bus for devices.
1964 * @bridge: PCI bridge for the bus to scan
1966 * Scan a PCI bus and child buses for new devices, add them,
1967 * and enable them, resizing bridge mmio/io resource if necessary
1968 * and possible. The caller must ensure the child devices are already
1969 * removed for resizing to occur.
1971 * Returns the max number of subordinate bus discovered.
1973 unsigned int __ref pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
1976 struct pci_bus *bus = bridge->subordinate;
1978 max = pci_scan_child_bus(bus);
1980 pci_assign_unassigned_bridge_resources(bridge);
1982 pci_bus_add_devices(bus);
1988 * pci_rescan_bus - scan a PCI bus for devices.
1989 * @bus: PCI bus to scan
1991 * Scan a PCI bus and child buses for new devices, adds them,
1994 * Returns the max number of subordinate bus discovered.
1996 unsigned int __ref pci_rescan_bus(struct pci_bus *bus)
2000 max = pci_scan_child_bus(bus);
2001 pci_assign_unassigned_bus_resources(bus);
2002 pci_bus_add_devices(bus);
2006 EXPORT_SYMBOL_GPL(pci_rescan_bus);
2008 EXPORT_SYMBOL(pci_add_new_bus);
2009 EXPORT_SYMBOL(pci_scan_slot);
2010 EXPORT_SYMBOL(pci_scan_bridge);
2011 EXPORT_SYMBOL_GPL(pci_scan_child_bus);
2014 * pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal
2015 * routines should always be executed under this mutex.
2017 static DEFINE_MUTEX(pci_rescan_remove_lock);
2019 void pci_lock_rescan_remove(void)
2021 mutex_lock(&pci_rescan_remove_lock);
2023 EXPORT_SYMBOL_GPL(pci_lock_rescan_remove);
2025 void pci_unlock_rescan_remove(void)
2027 mutex_unlock(&pci_rescan_remove_lock);
2029 EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove);
2031 static int __init pci_sort_bf_cmp(const struct device *d_a, const struct device *d_b)
2033 const struct pci_dev *a = to_pci_dev(d_a);
2034 const struct pci_dev *b = to_pci_dev(d_b);
2036 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
2037 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
2039 if (a->bus->number < b->bus->number) return -1;
2040 else if (a->bus->number > b->bus->number) return 1;
2042 if (a->devfn < b->devfn) return -1;
2043 else if (a->devfn > b->devfn) return 1;
2048 void __init pci_sort_breadthfirst(void)
2050 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);