1 // SPDX-License-Identifier: GPL-2.0
3 * PCI detection and setup code
6 #include <linux/kernel.h>
7 #include <linux/delay.h>
8 #include <linux/init.h>
10 #include <linux/msi.h>
11 #include <linux/of_device.h>
12 #include <linux/of_pci.h>
13 #include <linux/pci_hotplug.h>
14 #include <linux/slab.h>
15 #include <linux/module.h>
16 #include <linux/cpumask.h>
17 #include <linux/aer.h>
18 #include <linux/acpi.h>
19 #include <linux/hypervisor.h>
20 #include <linux/irqdomain.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/bitfield.h>
25 #define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
26 #define CARDBUS_RESERVE_BUSNR 3
28 static struct resource busn_resource = {
32 .flags = IORESOURCE_BUS,
35 /* Ugh. Need to stop exporting this to modules. */
36 LIST_HEAD(pci_root_buses);
37 EXPORT_SYMBOL(pci_root_buses);
39 static LIST_HEAD(pci_domain_busn_res_list);
41 struct pci_domain_busn_res {
42 struct list_head list;
47 static struct resource *get_pci_domain_busn_res(int domain_nr)
49 struct pci_domain_busn_res *r;
51 list_for_each_entry(r, &pci_domain_busn_res_list, list)
52 if (r->domain_nr == domain_nr)
55 r = kzalloc(sizeof(*r), GFP_KERNEL);
59 r->domain_nr = domain_nr;
62 r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
64 list_add_tail(&r->list, &pci_domain_busn_res_list);
70 * Some device drivers need know if PCI is initiated.
71 * Basically, we think PCI is not initiated when there
72 * is no device to be found on the pci_bus_type.
74 int no_pci_devices(void)
79 dev = bus_find_next_device(&pci_bus_type, NULL);
80 no_devices = (dev == NULL);
84 EXPORT_SYMBOL(no_pci_devices);
89 static void release_pcibus_dev(struct device *dev)
91 struct pci_bus *pci_bus = to_pci_bus(dev);
93 put_device(pci_bus->bridge);
94 pci_bus_remove_resources(pci_bus);
95 pci_release_bus_of_node(pci_bus);
99 static struct class pcibus_class = {
101 .dev_release = &release_pcibus_dev,
102 .dev_groups = pcibus_groups,
105 static int __init pcibus_class_init(void)
107 return class_register(&pcibus_class);
109 postcore_initcall(pcibus_class_init);
111 static u64 pci_size(u64 base, u64 maxbase, u64 mask)
113 u64 size = mask & maxbase; /* Find the significant bits */
118 * Get the lowest of them to find the decode size, and from that
121 size = size & ~(size-1);
124 * base == maxbase can be valid only if the BAR has already been
125 * programmed with all 1s.
127 if (base == maxbase && ((base | (size - 1)) & mask) != mask)
133 static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
138 if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
139 flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
140 flags |= IORESOURCE_IO;
144 flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
145 flags |= IORESOURCE_MEM;
146 if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
147 flags |= IORESOURCE_PREFETCH;
149 mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
151 case PCI_BASE_ADDRESS_MEM_TYPE_32:
153 case PCI_BASE_ADDRESS_MEM_TYPE_1M:
154 /* 1M mem BAR treated as 32-bit BAR */
156 case PCI_BASE_ADDRESS_MEM_TYPE_64:
157 flags |= IORESOURCE_MEM_64;
160 /* mem unknown type treated as 32-bit BAR */
166 #define PCI_COMMAND_DECODE_ENABLE (PCI_COMMAND_MEMORY | PCI_COMMAND_IO)
169 * __pci_read_base - Read a PCI BAR
170 * @dev: the PCI device
171 * @type: type of the BAR
172 * @res: resource buffer to be filled in
173 * @pos: BAR position in the config space
175 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
177 int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
178 struct resource *res, unsigned int pos)
180 u32 l = 0, sz = 0, mask;
181 u64 l64, sz64, mask64;
183 struct pci_bus_region region, inverted_region;
185 mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
187 /* No printks while decoding is disabled! */
188 if (!dev->mmio_always_on) {
189 pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
190 if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) {
191 pci_write_config_word(dev, PCI_COMMAND,
192 orig_cmd & ~PCI_COMMAND_DECODE_ENABLE);
196 res->name = pci_name(dev);
198 pci_read_config_dword(dev, pos, &l);
199 pci_write_config_dword(dev, pos, l | mask);
200 pci_read_config_dword(dev, pos, &sz);
201 pci_write_config_dword(dev, pos, l);
204 * All bits set in sz means the device isn't working properly.
205 * If the BAR isn't implemented, all bits must be 0. If it's a
206 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
209 if (PCI_POSSIBLE_ERROR(sz))
213 * I don't know how l can have all bits set. Copied from old code.
214 * Maybe it fixes a bug on some ancient platform.
216 if (PCI_POSSIBLE_ERROR(l))
219 if (type == pci_bar_unknown) {
220 res->flags = decode_bar(dev, l);
221 res->flags |= IORESOURCE_SIZEALIGN;
222 if (res->flags & IORESOURCE_IO) {
223 l64 = l & PCI_BASE_ADDRESS_IO_MASK;
224 sz64 = sz & PCI_BASE_ADDRESS_IO_MASK;
225 mask64 = PCI_BASE_ADDRESS_IO_MASK & (u32)IO_SPACE_LIMIT;
227 l64 = l & PCI_BASE_ADDRESS_MEM_MASK;
228 sz64 = sz & PCI_BASE_ADDRESS_MEM_MASK;
229 mask64 = (u32)PCI_BASE_ADDRESS_MEM_MASK;
232 if (l & PCI_ROM_ADDRESS_ENABLE)
233 res->flags |= IORESOURCE_ROM_ENABLE;
234 l64 = l & PCI_ROM_ADDRESS_MASK;
235 sz64 = sz & PCI_ROM_ADDRESS_MASK;
236 mask64 = PCI_ROM_ADDRESS_MASK;
239 if (res->flags & IORESOURCE_MEM_64) {
240 pci_read_config_dword(dev, pos + 4, &l);
241 pci_write_config_dword(dev, pos + 4, ~0);
242 pci_read_config_dword(dev, pos + 4, &sz);
243 pci_write_config_dword(dev, pos + 4, l);
245 l64 |= ((u64)l << 32);
246 sz64 |= ((u64)sz << 32);
247 mask64 |= ((u64)~0 << 32);
250 if (!dev->mmio_always_on && (orig_cmd & PCI_COMMAND_DECODE_ENABLE))
251 pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
256 sz64 = pci_size(l64, sz64, mask64);
258 pci_info(dev, FW_BUG "reg 0x%x: invalid BAR (can't size)\n",
263 if (res->flags & IORESOURCE_MEM_64) {
264 if ((sizeof(pci_bus_addr_t) < 8 || sizeof(resource_size_t) < 8)
265 && sz64 > 0x100000000ULL) {
266 res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
269 pci_err(dev, "reg 0x%x: can't handle BAR larger than 4GB (size %#010llx)\n",
270 pos, (unsigned long long)sz64);
274 if ((sizeof(pci_bus_addr_t) < 8) && l) {
275 /* Above 32-bit boundary; try to reallocate */
276 res->flags |= IORESOURCE_UNSET;
279 pci_info(dev, "reg 0x%x: can't handle BAR above 4GB (bus address %#010llx)\n",
280 pos, (unsigned long long)l64);
286 region.end = l64 + sz64 - 1;
288 pcibios_bus_to_resource(dev->bus, res, ®ion);
289 pcibios_resource_to_bus(dev->bus, &inverted_region, res);
292 * If "A" is a BAR value (a bus address), "bus_to_resource(A)" is
293 * the corresponding resource address (the physical address used by
294 * the CPU. Converting that resource address back to a bus address
295 * should yield the original BAR value:
297 * resource_to_bus(bus_to_resource(A)) == A
299 * If it doesn't, CPU accesses to "bus_to_resource(A)" will not
300 * be claimed by the device.
302 if (inverted_region.start != region.start) {
303 res->flags |= IORESOURCE_UNSET;
305 res->end = region.end - region.start;
306 pci_info(dev, "reg 0x%x: initial BAR value %#010llx invalid\n",
307 pos, (unsigned long long)region.start);
317 pci_info(dev, "reg 0x%x: %pR\n", pos, res);
319 return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
322 static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
324 unsigned int pos, reg;
326 if (dev->non_compliant_bars)
329 /* Per PCIe r4.0, sec 9.3.4.1.11, the VF BARs are all RO Zero */
333 for (pos = 0; pos < howmany; pos++) {
334 struct resource *res = &dev->resource[pos];
335 reg = PCI_BASE_ADDRESS_0 + (pos << 2);
336 pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
340 struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
341 dev->rom_base_reg = rom;
342 res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
343 IORESOURCE_READONLY | IORESOURCE_SIZEALIGN;
344 __pci_read_base(dev, pci_bar_mem32, res, rom);
348 static void pci_read_bridge_windows(struct pci_dev *bridge)
353 pci_read_config_word(bridge, PCI_IO_BASE, &io);
355 pci_write_config_word(bridge, PCI_IO_BASE, 0xe0f0);
356 pci_read_config_word(bridge, PCI_IO_BASE, &io);
357 pci_write_config_word(bridge, PCI_IO_BASE, 0x0);
360 bridge->io_window = 1;
363 * DECchip 21050 pass 2 errata: the bridge may miss an address
364 * disconnect boundary by one PCI data phase. Workaround: do not
365 * use prefetching on this device.
367 if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001)
370 pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
372 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE,
374 pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
375 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0);
380 bridge->pref_window = 1;
382 if ((pmem & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
385 * Bridge claims to have a 64-bit prefetchable memory
386 * window; verify that the upper bits are actually
389 pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &pmem);
390 pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32,
392 pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &tmp);
393 pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, pmem);
395 bridge->pref_64_window = 1;
399 static void pci_read_bridge_io(struct pci_bus *child)
401 struct pci_dev *dev = child->self;
402 u8 io_base_lo, io_limit_lo;
403 unsigned long io_mask, io_granularity, base, limit;
404 struct pci_bus_region region;
405 struct resource *res;
407 io_mask = PCI_IO_RANGE_MASK;
408 io_granularity = 0x1000;
409 if (dev->io_window_1k) {
410 /* Support 1K I/O space granularity */
411 io_mask = PCI_IO_1K_RANGE_MASK;
412 io_granularity = 0x400;
415 res = child->resource[0];
416 pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
417 pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
418 base = (io_base_lo & io_mask) << 8;
419 limit = (io_limit_lo & io_mask) << 8;
421 if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
422 u16 io_base_hi, io_limit_hi;
424 pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
425 pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
426 base |= ((unsigned long) io_base_hi << 16);
427 limit |= ((unsigned long) io_limit_hi << 16);
431 res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
433 region.end = limit + io_granularity - 1;
434 pcibios_bus_to_resource(dev->bus, res, ®ion);
435 pci_info(dev, " bridge window %pR\n", res);
439 static void pci_read_bridge_mmio(struct pci_bus *child)
441 struct pci_dev *dev = child->self;
442 u16 mem_base_lo, mem_limit_lo;
443 unsigned long base, limit;
444 struct pci_bus_region region;
445 struct resource *res;
447 res = child->resource[1];
448 pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
449 pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
450 base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
451 limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
453 res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
455 region.end = limit + 0xfffff;
456 pcibios_bus_to_resource(dev->bus, res, ®ion);
457 pci_info(dev, " bridge window %pR\n", res);
461 static void pci_read_bridge_mmio_pref(struct pci_bus *child)
463 struct pci_dev *dev = child->self;
464 u16 mem_base_lo, mem_limit_lo;
466 pci_bus_addr_t base, limit;
467 struct pci_bus_region region;
468 struct resource *res;
470 res = child->resource[2];
471 pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
472 pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
473 base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
474 limit64 = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
476 if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
477 u32 mem_base_hi, mem_limit_hi;
479 pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
480 pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
483 * Some bridges set the base > limit by default, and some
484 * (broken) BIOSes do not initialize them. If we find
485 * this, just assume they are not being used.
487 if (mem_base_hi <= mem_limit_hi) {
488 base64 |= (u64) mem_base_hi << 32;
489 limit64 |= (u64) mem_limit_hi << 32;
493 base = (pci_bus_addr_t) base64;
494 limit = (pci_bus_addr_t) limit64;
496 if (base != base64) {
497 pci_err(dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
498 (unsigned long long) base64);
503 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
504 IORESOURCE_MEM | IORESOURCE_PREFETCH;
505 if (res->flags & PCI_PREF_RANGE_TYPE_64)
506 res->flags |= IORESOURCE_MEM_64;
508 region.end = limit + 0xfffff;
509 pcibios_bus_to_resource(dev->bus, res, ®ion);
510 pci_info(dev, " bridge window %pR\n", res);
514 void pci_read_bridge_bases(struct pci_bus *child)
516 struct pci_dev *dev = child->self;
517 struct resource *res;
520 if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
523 pci_info(dev, "PCI bridge to %pR%s\n",
525 dev->transparent ? " (subtractive decode)" : "");
527 pci_bus_remove_resources(child);
528 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
529 child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
531 pci_read_bridge_io(child);
532 pci_read_bridge_mmio(child);
533 pci_read_bridge_mmio_pref(child);
535 if (dev->transparent) {
536 pci_bus_for_each_resource(child->parent, res, i) {
537 if (res && res->flags) {
538 pci_bus_add_resource(child, res,
539 PCI_SUBTRACTIVE_DECODE);
540 pci_info(dev, " bridge window %pR (subtractive decode)\n",
547 static struct pci_bus *pci_alloc_bus(struct pci_bus *parent)
551 b = kzalloc(sizeof(*b), GFP_KERNEL);
555 INIT_LIST_HEAD(&b->node);
556 INIT_LIST_HEAD(&b->children);
557 INIT_LIST_HEAD(&b->devices);
558 INIT_LIST_HEAD(&b->slots);
559 INIT_LIST_HEAD(&b->resources);
560 b->max_bus_speed = PCI_SPEED_UNKNOWN;
561 b->cur_bus_speed = PCI_SPEED_UNKNOWN;
562 #ifdef CONFIG_PCI_DOMAINS_GENERIC
564 b->domain_nr = parent->domain_nr;
569 static void pci_release_host_bridge_dev(struct device *dev)
571 struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
573 if (bridge->release_fn)
574 bridge->release_fn(bridge);
576 pci_free_resource_list(&bridge->windows);
577 pci_free_resource_list(&bridge->dma_ranges);
581 static void pci_init_host_bridge(struct pci_host_bridge *bridge)
583 INIT_LIST_HEAD(&bridge->windows);
584 INIT_LIST_HEAD(&bridge->dma_ranges);
587 * We assume we can manage these PCIe features. Some systems may
588 * reserve these for use by the platform itself, e.g., an ACPI BIOS
589 * may implement its own AER handling and use _OSC to prevent the
590 * OS from interfering.
592 bridge->native_aer = 1;
593 bridge->native_pcie_hotplug = 1;
594 bridge->native_shpc_hotplug = 1;
595 bridge->native_pme = 1;
596 bridge->native_ltr = 1;
597 bridge->native_dpc = 1;
598 bridge->domain_nr = PCI_DOMAIN_NR_NOT_SET;
600 device_initialize(&bridge->dev);
603 struct pci_host_bridge *pci_alloc_host_bridge(size_t priv)
605 struct pci_host_bridge *bridge;
607 bridge = kzalloc(sizeof(*bridge) + priv, GFP_KERNEL);
611 pci_init_host_bridge(bridge);
612 bridge->dev.release = pci_release_host_bridge_dev;
616 EXPORT_SYMBOL(pci_alloc_host_bridge);
618 static void devm_pci_alloc_host_bridge_release(void *data)
620 pci_free_host_bridge(data);
623 struct pci_host_bridge *devm_pci_alloc_host_bridge(struct device *dev,
627 struct pci_host_bridge *bridge;
629 bridge = pci_alloc_host_bridge(priv);
633 bridge->dev.parent = dev;
635 ret = devm_add_action_or_reset(dev, devm_pci_alloc_host_bridge_release,
640 ret = devm_of_pci_bridge_init(dev, bridge);
646 EXPORT_SYMBOL(devm_pci_alloc_host_bridge);
648 void pci_free_host_bridge(struct pci_host_bridge *bridge)
650 put_device(&bridge->dev);
652 EXPORT_SYMBOL(pci_free_host_bridge);
654 /* Indexed by PCI_X_SSTATUS_FREQ (secondary bus mode and frequency) */
655 static const unsigned char pcix_bus_speed[] = {
656 PCI_SPEED_UNKNOWN, /* 0 */
657 PCI_SPEED_66MHz_PCIX, /* 1 */
658 PCI_SPEED_100MHz_PCIX, /* 2 */
659 PCI_SPEED_133MHz_PCIX, /* 3 */
660 PCI_SPEED_UNKNOWN, /* 4 */
661 PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
662 PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
663 PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
664 PCI_SPEED_UNKNOWN, /* 8 */
665 PCI_SPEED_66MHz_PCIX_266, /* 9 */
666 PCI_SPEED_100MHz_PCIX_266, /* A */
667 PCI_SPEED_133MHz_PCIX_266, /* B */
668 PCI_SPEED_UNKNOWN, /* C */
669 PCI_SPEED_66MHz_PCIX_533, /* D */
670 PCI_SPEED_100MHz_PCIX_533, /* E */
671 PCI_SPEED_133MHz_PCIX_533 /* F */
674 /* Indexed by PCI_EXP_LNKCAP_SLS, PCI_EXP_LNKSTA_CLS */
675 const unsigned char pcie_link_speed[] = {
676 PCI_SPEED_UNKNOWN, /* 0 */
677 PCIE_SPEED_2_5GT, /* 1 */
678 PCIE_SPEED_5_0GT, /* 2 */
679 PCIE_SPEED_8_0GT, /* 3 */
680 PCIE_SPEED_16_0GT, /* 4 */
681 PCIE_SPEED_32_0GT, /* 5 */
682 PCIE_SPEED_64_0GT, /* 6 */
683 PCI_SPEED_UNKNOWN, /* 7 */
684 PCI_SPEED_UNKNOWN, /* 8 */
685 PCI_SPEED_UNKNOWN, /* 9 */
686 PCI_SPEED_UNKNOWN, /* A */
687 PCI_SPEED_UNKNOWN, /* B */
688 PCI_SPEED_UNKNOWN, /* C */
689 PCI_SPEED_UNKNOWN, /* D */
690 PCI_SPEED_UNKNOWN, /* E */
691 PCI_SPEED_UNKNOWN /* F */
693 EXPORT_SYMBOL_GPL(pcie_link_speed);
695 const char *pci_speed_string(enum pci_bus_speed speed)
697 /* Indexed by the pci_bus_speed enum */
698 static const char *speed_strings[] = {
699 "33 MHz PCI", /* 0x00 */
700 "66 MHz PCI", /* 0x01 */
701 "66 MHz PCI-X", /* 0x02 */
702 "100 MHz PCI-X", /* 0x03 */
703 "133 MHz PCI-X", /* 0x04 */
708 "66 MHz PCI-X 266", /* 0x09 */
709 "100 MHz PCI-X 266", /* 0x0a */
710 "133 MHz PCI-X 266", /* 0x0b */
711 "Unknown AGP", /* 0x0c */
716 "66 MHz PCI-X 533", /* 0x11 */
717 "100 MHz PCI-X 533", /* 0x12 */
718 "133 MHz PCI-X 533", /* 0x13 */
719 "2.5 GT/s PCIe", /* 0x14 */
720 "5.0 GT/s PCIe", /* 0x15 */
721 "8.0 GT/s PCIe", /* 0x16 */
722 "16.0 GT/s PCIe", /* 0x17 */
723 "32.0 GT/s PCIe", /* 0x18 */
724 "64.0 GT/s PCIe", /* 0x19 */
727 if (speed < ARRAY_SIZE(speed_strings))
728 return speed_strings[speed];
731 EXPORT_SYMBOL_GPL(pci_speed_string);
733 void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
735 bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS];
737 EXPORT_SYMBOL_GPL(pcie_update_link_speed);
739 static unsigned char agp_speeds[] = {
747 static enum pci_bus_speed agp_speed(int agp3, int agpstat)
753 else if (agpstat & 2)
755 else if (agpstat & 1)
767 return agp_speeds[index];
770 static void pci_set_bus_speed(struct pci_bus *bus)
772 struct pci_dev *bridge = bus->self;
775 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
777 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
781 pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
782 bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
784 pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
785 bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
788 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
791 enum pci_bus_speed max;
793 pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
796 if (status & PCI_X_SSTATUS_533MHZ) {
797 max = PCI_SPEED_133MHz_PCIX_533;
798 } else if (status & PCI_X_SSTATUS_266MHZ) {
799 max = PCI_SPEED_133MHz_PCIX_266;
800 } else if (status & PCI_X_SSTATUS_133MHZ) {
801 if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2)
802 max = PCI_SPEED_133MHz_PCIX_ECC;
804 max = PCI_SPEED_133MHz_PCIX;
806 max = PCI_SPEED_66MHz_PCIX;
809 bus->max_bus_speed = max;
810 bus->cur_bus_speed = pcix_bus_speed[
811 (status & PCI_X_SSTATUS_FREQ) >> 6];
816 if (pci_is_pcie(bridge)) {
820 pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
821 bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
822 bridge->link_active_reporting = !!(linkcap & PCI_EXP_LNKCAP_DLLLARC);
824 pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
825 pcie_update_link_speed(bus, linksta);
829 static struct irq_domain *pci_host_bridge_msi_domain(struct pci_bus *bus)
831 struct irq_domain *d;
833 /* If the host bridge driver sets a MSI domain of the bridge, use it */
834 d = dev_get_msi_domain(bus->bridge);
837 * Any firmware interface that can resolve the msi_domain
838 * should be called from here.
841 d = pci_host_bridge_of_msi_domain(bus);
843 d = pci_host_bridge_acpi_msi_domain(bus);
845 #ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
847 * If no IRQ domain was found via the OF tree, try looking it up
848 * directly through the fwnode_handle.
851 struct fwnode_handle *fwnode = pci_root_bus_fwnode(bus);
854 d = irq_find_matching_fwnode(fwnode,
862 static void pci_set_bus_msi_domain(struct pci_bus *bus)
864 struct irq_domain *d;
868 * The bus can be a root bus, a subordinate bus, or a virtual bus
869 * created by an SR-IOV device. Walk up to the first bridge device
870 * found or derive the domain from the host bridge.
872 for (b = bus, d = NULL; !d && !pci_is_root_bus(b); b = b->parent) {
874 d = dev_get_msi_domain(&b->self->dev);
878 d = pci_host_bridge_msi_domain(b);
880 dev_set_msi_domain(&bus->dev, d);
883 static int pci_register_host_bridge(struct pci_host_bridge *bridge)
885 struct device *parent = bridge->dev.parent;
886 struct resource_entry *window, *next, *n;
887 struct pci_bus *bus, *b;
888 resource_size_t offset, next_offset;
889 LIST_HEAD(resources);
890 struct resource *res, *next_res;
895 bus = pci_alloc_bus(NULL);
901 bus->sysdata = bridge->sysdata;
902 bus->ops = bridge->ops;
903 bus->number = bus->busn_res.start = bridge->busnr;
904 #ifdef CONFIG_PCI_DOMAINS_GENERIC
905 if (bridge->domain_nr == PCI_DOMAIN_NR_NOT_SET)
906 bus->domain_nr = pci_bus_find_domain_nr(bus, parent);
908 bus->domain_nr = bridge->domain_nr;
911 b = pci_find_bus(pci_domain_nr(bus), bridge->busnr);
913 /* Ignore it if we already got here via a different bridge */
914 dev_dbg(&b->dev, "bus already known\n");
919 dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(bus),
922 err = pcibios_root_bridge_prepare(bridge);
926 /* Temporarily move resources off the list */
927 list_splice_init(&bridge->windows, &resources);
928 err = device_add(&bridge->dev);
930 put_device(&bridge->dev);
933 bus->bridge = get_device(&bridge->dev);
934 device_enable_async_suspend(bus->bridge);
935 pci_set_bus_of_node(bus);
936 pci_set_bus_msi_domain(bus);
937 if (bridge->msi_domain && !dev_get_msi_domain(&bus->dev) &&
938 !pci_host_of_has_msi_map(parent))
939 bus->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
942 set_dev_node(bus->bridge, pcibus_to_node(bus));
944 bus->dev.class = &pcibus_class;
945 bus->dev.parent = bus->bridge;
947 dev_set_name(&bus->dev, "%04x:%02x", pci_domain_nr(bus), bus->number);
948 name = dev_name(&bus->dev);
950 err = device_register(&bus->dev);
954 pcibios_add_bus(bus);
956 if (bus->ops->add_bus) {
957 err = bus->ops->add_bus(bus);
958 if (WARN_ON(err < 0))
959 dev_err(&bus->dev, "failed to add bus: %d\n", err);
962 /* Create legacy_io and legacy_mem files for this bus */
963 pci_create_legacy_files(bus);
966 dev_info(parent, "PCI host bridge to bus %s\n", name);
968 pr_info("PCI host bridge to bus %s\n", name);
970 if (nr_node_ids > 1 && pcibus_to_node(bus) == NUMA_NO_NODE)
971 dev_warn(&bus->dev, "Unknown NUMA node; performance will be reduced\n");
973 /* Coalesce contiguous windows */
974 resource_list_for_each_entry_safe(window, n, &resources) {
975 if (list_is_last(&window->node, &resources))
978 next = list_next_entry(window, node);
979 offset = window->offset;
981 next_offset = next->offset;
982 next_res = next->res;
984 if (res->flags != next_res->flags || offset != next_offset)
987 if (res->end + 1 == next_res->start) {
988 next_res->start = res->start;
989 res->flags = res->start = res->end = 0;
993 /* Add initial resources to the bus */
994 resource_list_for_each_entry_safe(window, n, &resources) {
995 offset = window->offset;
1000 list_move_tail(&window->node, &bridge->windows);
1002 if (res->flags & IORESOURCE_BUS)
1003 pci_bus_insert_busn_res(bus, bus->number, res->end);
1005 pci_bus_add_resource(bus, res, 0);
1008 if (resource_type(res) == IORESOURCE_IO)
1009 fmt = " (bus address [%#06llx-%#06llx])";
1011 fmt = " (bus address [%#010llx-%#010llx])";
1013 snprintf(addr, sizeof(addr), fmt,
1014 (unsigned long long)(res->start - offset),
1015 (unsigned long long)(res->end - offset));
1019 dev_info(&bus->dev, "root bus resource %pR%s\n", res, addr);
1022 down_write(&pci_bus_sem);
1023 list_add_tail(&bus->node, &pci_root_buses);
1024 up_write(&pci_bus_sem);
1029 put_device(&bridge->dev);
1030 device_del(&bridge->dev);
1037 static bool pci_bridge_child_ext_cfg_accessible(struct pci_dev *bridge)
1043 * If extended config space isn't accessible on a bridge's primary
1044 * bus, we certainly can't access it on the secondary bus.
1046 if (bridge->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG)
1050 * PCIe Root Ports and switch ports are PCIe on both sides, so if
1051 * extended config space is accessible on the primary, it's also
1052 * accessible on the secondary.
1054 if (pci_is_pcie(bridge) &&
1055 (pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT ||
1056 pci_pcie_type(bridge) == PCI_EXP_TYPE_UPSTREAM ||
1057 pci_pcie_type(bridge) == PCI_EXP_TYPE_DOWNSTREAM))
1061 * For the other bridge types:
1062 * - PCI-to-PCI bridges
1063 * - PCIe-to-PCI/PCI-X forward bridges
1064 * - PCI/PCI-X-to-PCIe reverse bridges
1065 * extended config space on the secondary side is only accessible
1066 * if the bridge supports PCI-X Mode 2.
1068 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
1072 pci_read_config_dword(bridge, pos + PCI_X_STATUS, &status);
1073 return status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ);
1076 static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
1077 struct pci_dev *bridge, int busnr)
1079 struct pci_bus *child;
1080 struct pci_host_bridge *host;
1084 /* Allocate a new bus and inherit stuff from the parent */
1085 child = pci_alloc_bus(parent);
1089 child->parent = parent;
1090 child->sysdata = parent->sysdata;
1091 child->bus_flags = parent->bus_flags;
1093 host = pci_find_host_bridge(parent);
1094 if (host->child_ops)
1095 child->ops = host->child_ops;
1097 child->ops = parent->ops;
1100 * Initialize some portions of the bus device, but don't register
1101 * it now as the parent is not properly set up yet.
1103 child->dev.class = &pcibus_class;
1104 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
1106 /* Set up the primary, secondary and subordinate bus numbers */
1107 child->number = child->busn_res.start = busnr;
1108 child->primary = parent->busn_res.start;
1109 child->busn_res.end = 0xff;
1112 child->dev.parent = parent->bridge;
1116 child->self = bridge;
1117 child->bridge = get_device(&bridge->dev);
1118 child->dev.parent = child->bridge;
1119 pci_set_bus_of_node(child);
1120 pci_set_bus_speed(child);
1123 * Check whether extended config space is accessible on the child
1124 * bus. Note that we currently assume it is always accessible on
1127 if (!pci_bridge_child_ext_cfg_accessible(bridge)) {
1128 child->bus_flags |= PCI_BUS_FLAGS_NO_EXTCFG;
1129 pci_info(child, "extended config space not accessible\n");
1132 /* Set up default resource pointers and names */
1133 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
1134 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
1135 child->resource[i]->name = child->name;
1137 bridge->subordinate = child;
1140 pci_set_bus_msi_domain(child);
1141 ret = device_register(&child->dev);
1144 pcibios_add_bus(child);
1146 if (child->ops->add_bus) {
1147 ret = child->ops->add_bus(child);
1148 if (WARN_ON(ret < 0))
1149 dev_err(&child->dev, "failed to add bus: %d\n", ret);
1152 /* Create legacy_io and legacy_mem files for this bus */
1153 pci_create_legacy_files(child);
1158 struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev,
1161 struct pci_bus *child;
1163 child = pci_alloc_child_bus(parent, dev, busnr);
1165 down_write(&pci_bus_sem);
1166 list_add_tail(&child->node, &parent->children);
1167 up_write(&pci_bus_sem);
1171 EXPORT_SYMBOL(pci_add_new_bus);
1173 static void pci_enable_crs(struct pci_dev *pdev)
1177 /* Enable CRS Software Visibility if supported */
1178 pcie_capability_read_word(pdev, PCI_EXP_RTCAP, &root_cap);
1179 if (root_cap & PCI_EXP_RTCAP_CRSVIS)
1180 pcie_capability_set_word(pdev, PCI_EXP_RTCTL,
1181 PCI_EXP_RTCTL_CRSSVE);
1184 static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
1185 unsigned int available_buses);
1187 * pci_ea_fixed_busnrs() - Read fixed Secondary and Subordinate bus
1188 * numbers from EA capability.
1190 * @sec: updated with secondary bus number from EA
1191 * @sub: updated with subordinate bus number from EA
1193 * If @dev is a bridge with EA capability that specifies valid secondary
1194 * and subordinate bus numbers, return true with the bus numbers in @sec
1195 * and @sub. Otherwise return false.
1197 static bool pci_ea_fixed_busnrs(struct pci_dev *dev, u8 *sec, u8 *sub)
1203 if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE)
1206 /* find PCI EA capability in list */
1207 ea = pci_find_capability(dev, PCI_CAP_ID_EA);
1211 offset = ea + PCI_EA_FIRST_ENT;
1212 pci_read_config_dword(dev, offset, &dw);
1213 ea_sec = dw & PCI_EA_SEC_BUS_MASK;
1214 ea_sub = (dw & PCI_EA_SUB_BUS_MASK) >> PCI_EA_SUB_BUS_SHIFT;
1215 if (ea_sec == 0 || ea_sub < ea_sec)
1224 * pci_scan_bridge_extend() - Scan buses behind a bridge
1225 * @bus: Parent bus the bridge is on
1226 * @dev: Bridge itself
1227 * @max: Starting subordinate number of buses behind this bridge
1228 * @available_buses: Total number of buses available for this bridge and
1229 * the devices below. After the minimal bus space has
1230 * been allocated the remaining buses will be
1231 * distributed equally between hotplug-capable bridges.
1232 * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges
1233 * that need to be reconfigured.
1235 * If it's a bridge, configure it and scan the bus behind it.
1236 * For CardBus bridges, we don't scan behind as the devices will
1237 * be handled by the bridge driver itself.
1239 * We need to process bridges in two passes -- first we scan those
1240 * already configured by the BIOS and after we are done with all of
1241 * them, we proceed to assigning numbers to the remaining buses in
1242 * order to avoid overlaps between old and new bus numbers.
1244 * Return: New subordinate number covering all buses behind this bridge.
1246 static int pci_scan_bridge_extend(struct pci_bus *bus, struct pci_dev *dev,
1247 int max, unsigned int available_buses,
1250 struct pci_bus *child;
1251 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
1252 u32 buses, i, j = 0;
1254 u8 primary, secondary, subordinate;
1257 u8 fixed_sec, fixed_sub;
1261 * Make sure the bridge is powered on to be able to access config
1262 * space of devices below it.
1264 pm_runtime_get_sync(&dev->dev);
1266 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
1267 primary = buses & 0xFF;
1268 secondary = (buses >> 8) & 0xFF;
1269 subordinate = (buses >> 16) & 0xFF;
1271 pci_dbg(dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
1272 secondary, subordinate, pass);
1274 if (!primary && (primary != bus->number) && secondary && subordinate) {
1275 pci_warn(dev, "Primary bus is hard wired to 0\n");
1276 primary = bus->number;
1279 /* Check if setup is sensible at all */
1281 (primary != bus->number || secondary <= bus->number ||
1282 secondary > subordinate)) {
1283 pci_info(dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
1284 secondary, subordinate);
1289 * Disable Master-Abort Mode during probing to avoid reporting of
1290 * bus errors in some architectures.
1292 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
1293 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
1294 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
1296 pci_enable_crs(dev);
1298 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
1299 !is_cardbus && !broken) {
1303 * Bus already configured by firmware, process it in the
1304 * first pass and just note the configuration.
1310 * The bus might already exist for two reasons: Either we
1311 * are rescanning the bus or the bus is reachable through
1312 * more than one bridge. The second case can happen with
1313 * the i450NX chipset.
1315 child = pci_find_bus(pci_domain_nr(bus), secondary);
1317 child = pci_add_new_bus(bus, dev, secondary);
1320 child->primary = primary;
1321 pci_bus_insert_busn_res(child, secondary, subordinate);
1322 child->bridge_ctl = bctl;
1325 cmax = pci_scan_child_bus(child);
1326 if (cmax > subordinate)
1327 pci_warn(dev, "bridge has subordinate %02x but max busn %02x\n",
1330 /* Subordinate should equal child->busn_res.end */
1331 if (subordinate > max)
1336 * We need to assign a number to this bus which we always
1337 * do in the second pass.
1340 if (pcibios_assign_all_busses() || broken || is_cardbus)
1343 * Temporarily disable forwarding of the
1344 * configuration cycles on all bridges in
1345 * this bus segment to avoid possible
1346 * conflicts in the second pass between two
1347 * bridges programmed with overlapping bus
1350 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
1356 pci_write_config_word(dev, PCI_STATUS, 0xffff);
1358 /* Read bus numbers from EA Capability (if present) */
1359 fixed_buses = pci_ea_fixed_busnrs(dev, &fixed_sec, &fixed_sub);
1361 next_busnr = fixed_sec;
1363 next_busnr = max + 1;
1366 * Prevent assigning a bus number that already exists.
1367 * This can happen when a bridge is hot-plugged, so in this
1368 * case we only re-scan this bus.
1370 child = pci_find_bus(pci_domain_nr(bus), next_busnr);
1372 child = pci_add_new_bus(bus, dev, next_busnr);
1375 pci_bus_insert_busn_res(child, next_busnr,
1379 if (available_buses)
1382 buses = (buses & 0xff000000)
1383 | ((unsigned int)(child->primary) << 0)
1384 | ((unsigned int)(child->busn_res.start) << 8)
1385 | ((unsigned int)(child->busn_res.end) << 16);
1388 * yenta.c forces a secondary latency timer of 176.
1389 * Copy that behaviour here.
1392 buses &= ~0xff000000;
1393 buses |= CARDBUS_LATENCY_TIMER << 24;
1396 /* We need to blast all three values with a single write */
1397 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
1400 child->bridge_ctl = bctl;
1401 max = pci_scan_child_bus_extend(child, available_buses);
1405 * For CardBus bridges, we leave 4 bus numbers as
1406 * cards with a PCI-to-PCI bridge can be inserted
1409 for (i = 0; i < CARDBUS_RESERVE_BUSNR; i++) {
1410 struct pci_bus *parent = bus;
1411 if (pci_find_bus(pci_domain_nr(bus),
1414 while (parent->parent) {
1415 if ((!pcibios_assign_all_busses()) &&
1416 (parent->busn_res.end > max) &&
1417 (parent->busn_res.end <= max+i)) {
1420 parent = parent->parent;
1425 * Often, there are two CardBus
1426 * bridges -- try to leave one
1427 * valid bus number for each one.
1437 * Set subordinate bus number to its real value.
1438 * If fixed subordinate bus number exists from EA
1439 * capability then use it.
1443 pci_bus_update_busn_res_end(child, max);
1444 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
1447 sprintf(child->name,
1448 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
1449 pci_domain_nr(bus), child->number);
1451 /* Check that all devices are accessible */
1452 while (bus->parent) {
1453 if ((child->busn_res.end > bus->busn_res.end) ||
1454 (child->number > bus->busn_res.end) ||
1455 (child->number < bus->number) ||
1456 (child->busn_res.end < bus->number)) {
1457 dev_info(&dev->dev, "devices behind bridge are unusable because %pR cannot be assigned for them\n",
1465 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
1467 pm_runtime_put(&dev->dev);
1473 * pci_scan_bridge() - Scan buses behind a bridge
1474 * @bus: Parent bus the bridge is on
1475 * @dev: Bridge itself
1476 * @max: Starting subordinate number of buses behind this bridge
1477 * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges
1478 * that need to be reconfigured.
1480 * If it's a bridge, configure it and scan the bus behind it.
1481 * For CardBus bridges, we don't scan behind as the devices will
1482 * be handled by the bridge driver itself.
1484 * We need to process bridges in two passes -- first we scan those
1485 * already configured by the BIOS and after we are done with all of
1486 * them, we proceed to assigning numbers to the remaining buses in
1487 * order to avoid overlaps between old and new bus numbers.
1489 * Return: New subordinate number covering all buses behind this bridge.
1491 int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
1493 return pci_scan_bridge_extend(bus, dev, max, 0, pass);
1495 EXPORT_SYMBOL(pci_scan_bridge);
1498 * Read interrupt line and base address registers.
1499 * The architecture-dependent code can tweak these, of course.
1501 static void pci_read_irq(struct pci_dev *dev)
1505 /* VFs are not allowed to use INTx, so skip the config reads */
1506 if (dev->is_virtfn) {
1512 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
1515 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
1519 void set_pcie_port_type(struct pci_dev *pdev)
1524 struct pci_dev *parent;
1526 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
1530 pdev->pcie_cap = pos;
1531 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
1532 pdev->pcie_flags_reg = reg16;
1533 pci_read_config_dword(pdev, pos + PCI_EXP_DEVCAP, &pdev->devcap);
1534 pdev->pcie_mpss = FIELD_GET(PCI_EXP_DEVCAP_PAYLOAD, pdev->devcap);
1536 parent = pci_upstream_bridge(pdev);
1541 * Some systems do not identify their upstream/downstream ports
1542 * correctly so detect impossible configurations here and correct
1543 * the port type accordingly.
1545 type = pci_pcie_type(pdev);
1546 if (type == PCI_EXP_TYPE_DOWNSTREAM) {
1548 * If pdev claims to be downstream port but the parent
1549 * device is also downstream port assume pdev is actually
1552 if (pcie_downstream_port(parent)) {
1553 pci_info(pdev, "claims to be downstream port but is acting as upstream port, correcting type\n");
1554 pdev->pcie_flags_reg &= ~PCI_EXP_FLAGS_TYPE;
1555 pdev->pcie_flags_reg |= PCI_EXP_TYPE_UPSTREAM;
1557 } else if (type == PCI_EXP_TYPE_UPSTREAM) {
1559 * If pdev claims to be upstream port but the parent
1560 * device is also upstream port assume pdev is actually
1563 if (pci_pcie_type(parent) == PCI_EXP_TYPE_UPSTREAM) {
1564 pci_info(pdev, "claims to be upstream port but is acting as downstream port, correcting type\n");
1565 pdev->pcie_flags_reg &= ~PCI_EXP_FLAGS_TYPE;
1566 pdev->pcie_flags_reg |= PCI_EXP_TYPE_DOWNSTREAM;
1571 void set_pcie_hotplug_bridge(struct pci_dev *pdev)
1575 pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32);
1576 if (reg32 & PCI_EXP_SLTCAP_HPC)
1577 pdev->is_hotplug_bridge = 1;
1580 static void set_pcie_thunderbolt(struct pci_dev *dev)
1584 /* Is the device part of a Thunderbolt controller? */
1585 vsec = pci_find_vsec_capability(dev, PCI_VENDOR_ID_INTEL, PCI_VSEC_ID_INTEL_TBT);
1587 dev->is_thunderbolt = 1;
1590 static void set_pcie_untrusted(struct pci_dev *dev)
1592 struct pci_dev *parent;
1595 * If the upstream bridge is untrusted we treat this device
1596 * untrusted as well.
1598 parent = pci_upstream_bridge(dev);
1599 if (parent && (parent->untrusted || parent->external_facing))
1600 dev->untrusted = true;
1603 static void pci_set_removable(struct pci_dev *dev)
1605 struct pci_dev *parent = pci_upstream_bridge(dev);
1608 * We (only) consider everything downstream from an external_facing
1609 * device to be removable by the user. We're mainly concerned with
1610 * consumer platforms with user accessible thunderbolt ports that are
1611 * vulnerable to DMA attacks, and we expect those ports to be marked by
1612 * the firmware as external_facing. Devices in traditional hotplug
1613 * slots can technically be removed, but the expectation is that unless
1614 * the port is marked with external_facing, such devices are less
1615 * accessible to user / may not be removed by end user, and thus not
1616 * exposed as "removable" to userspace.
1619 (parent->external_facing || dev_is_removable(&parent->dev)))
1620 dev_set_removable(&dev->dev, DEVICE_REMOVABLE);
1624 * pci_ext_cfg_is_aliased - Is ext config space just an alias of std config?
1627 * PCI Express to PCI/PCI-X Bridge Specification, rev 1.0, 4.1.4 says that
1628 * when forwarding a type1 configuration request the bridge must check that
1629 * the extended register address field is zero. The bridge is not permitted
1630 * to forward the transactions and must handle it as an Unsupported Request.
1631 * Some bridges do not follow this rule and simply drop the extended register
1632 * bits, resulting in the standard config space being aliased, every 256
1633 * bytes across the entire configuration space. Test for this condition by
1634 * comparing the first dword of each potential alias to the vendor/device ID.
1636 * ASM1083/1085 PCIe-to-PCI Reversible Bridge (1b21:1080, rev 01 & 03)
1637 * AMD/ATI SBx00 PCI to PCI Bridge (1002:4384, rev 40)
1639 static bool pci_ext_cfg_is_aliased(struct pci_dev *dev)
1641 #ifdef CONFIG_PCI_QUIRKS
1645 pci_read_config_dword(dev, PCI_VENDOR_ID, &header);
1647 for (pos = PCI_CFG_SPACE_SIZE;
1648 pos < PCI_CFG_SPACE_EXP_SIZE; pos += PCI_CFG_SPACE_SIZE) {
1649 if (pci_read_config_dword(dev, pos, &tmp) != PCIBIOS_SUCCESSFUL
1661 * pci_cfg_space_size_ext - Get the configuration space size of the PCI device
1664 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1665 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1666 * access it. Maybe we don't have a way to generate extended config space
1667 * accesses, or the device is behind a reverse Express bridge. So we try
1668 * reading the dword at 0x100 which must either be 0 or a valid extended
1669 * capability header.
1671 static int pci_cfg_space_size_ext(struct pci_dev *dev)
1674 int pos = PCI_CFG_SPACE_SIZE;
1676 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1677 return PCI_CFG_SPACE_SIZE;
1678 if (PCI_POSSIBLE_ERROR(status) || pci_ext_cfg_is_aliased(dev))
1679 return PCI_CFG_SPACE_SIZE;
1681 return PCI_CFG_SPACE_EXP_SIZE;
1684 int pci_cfg_space_size(struct pci_dev *dev)
1690 #ifdef CONFIG_PCI_IOV
1692 * Per the SR-IOV specification (rev 1.1, sec 3.5), VFs are required to
1693 * implement a PCIe capability and therefore must implement extended
1694 * config space. We can skip the NO_EXTCFG test below and the
1695 * reachability/aliasing test in pci_cfg_space_size_ext() by virtue of
1696 * the fact that the SR-IOV capability on the PF resides in extended
1697 * config space and must be accessible and non-aliased to have enabled
1698 * support for this VF. This is a micro performance optimization for
1699 * systems supporting many VFs.
1702 return PCI_CFG_SPACE_EXP_SIZE;
1705 if (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG)
1706 return PCI_CFG_SPACE_SIZE;
1708 class = dev->class >> 8;
1709 if (class == PCI_CLASS_BRIDGE_HOST)
1710 return pci_cfg_space_size_ext(dev);
1712 if (pci_is_pcie(dev))
1713 return pci_cfg_space_size_ext(dev);
1715 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1717 return PCI_CFG_SPACE_SIZE;
1719 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1720 if (status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ))
1721 return pci_cfg_space_size_ext(dev);
1723 return PCI_CFG_SPACE_SIZE;
1726 static u32 pci_class(struct pci_dev *dev)
1730 #ifdef CONFIG_PCI_IOV
1732 return dev->physfn->sriov->class;
1734 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
1738 static void pci_subsystem_ids(struct pci_dev *dev, u16 *vendor, u16 *device)
1740 #ifdef CONFIG_PCI_IOV
1741 if (dev->is_virtfn) {
1742 *vendor = dev->physfn->sriov->subsystem_vendor;
1743 *device = dev->physfn->sriov->subsystem_device;
1747 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, vendor);
1748 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, device);
1751 static u8 pci_hdr_type(struct pci_dev *dev)
1755 #ifdef CONFIG_PCI_IOV
1757 return dev->physfn->sriov->hdr_type;
1759 pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type);
1763 #define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
1766 * pci_intx_mask_broken - Test PCI_COMMAND_INTX_DISABLE writability
1769 * Test whether PCI_COMMAND_INTX_DISABLE is writable for @dev. Check this
1770 * at enumeration-time to avoid modifying PCI_COMMAND at run-time.
1772 static int pci_intx_mask_broken(struct pci_dev *dev)
1774 u16 orig, toggle, new;
1776 pci_read_config_word(dev, PCI_COMMAND, &orig);
1777 toggle = orig ^ PCI_COMMAND_INTX_DISABLE;
1778 pci_write_config_word(dev, PCI_COMMAND, toggle);
1779 pci_read_config_word(dev, PCI_COMMAND, &new);
1781 pci_write_config_word(dev, PCI_COMMAND, orig);
1784 * PCI_COMMAND_INTX_DISABLE was reserved and read-only prior to PCI
1785 * r2.3, so strictly speaking, a device is not *broken* if it's not
1786 * writable. But we'll live with the misnomer for now.
1793 static void early_dump_pci_device(struct pci_dev *pdev)
1798 pci_info(pdev, "config space:\n");
1800 for (i = 0; i < 256; i += 4)
1801 pci_read_config_dword(pdev, i, &value[i / 4]);
1803 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 1,
1808 * pci_setup_device - Fill in class and map information of a device
1809 * @dev: the device structure to fill
1811 * Initialize the device structure with information about the device's
1812 * vendor,class,memory and IO-space addresses, IRQ lines etc.
1813 * Called at initialisation of the PCI subsystem and by CardBus services.
1814 * Returns 0 on success and negative if unknown type of device (not normal,
1815 * bridge or CardBus).
1817 int pci_setup_device(struct pci_dev *dev)
1823 struct pci_bus_region region;
1824 struct resource *res;
1826 hdr_type = pci_hdr_type(dev);
1828 dev->sysdata = dev->bus->sysdata;
1829 dev->dev.parent = dev->bus->bridge;
1830 dev->dev.bus = &pci_bus_type;
1831 dev->hdr_type = hdr_type & 0x7f;
1832 dev->multifunction = !!(hdr_type & 0x80);
1833 dev->error_state = pci_channel_io_normal;
1834 set_pcie_port_type(dev);
1836 pci_set_of_node(dev);
1837 pci_set_acpi_fwnode(dev);
1839 pci_dev_assign_slot(dev);
1842 * Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
1843 * set this higher, assuming the system even supports it.
1845 dev->dma_mask = 0xffffffff;
1847 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
1848 dev->bus->number, PCI_SLOT(dev->devfn),
1849 PCI_FUNC(dev->devfn));
1851 class = pci_class(dev);
1853 dev->revision = class & 0xff;
1854 dev->class = class >> 8; /* upper 3 bytes */
1857 early_dump_pci_device(dev);
1859 /* Need to have dev->class ready */
1860 dev->cfg_size = pci_cfg_space_size(dev);
1862 /* Need to have dev->cfg_size ready */
1863 set_pcie_thunderbolt(dev);
1865 set_pcie_untrusted(dev);
1867 /* "Unknown power state" */
1868 dev->current_state = PCI_UNKNOWN;
1870 /* Early fixups, before probing the BARs */
1871 pci_fixup_device(pci_fixup_early, dev);
1873 pci_set_removable(dev);
1875 pci_info(dev, "[%04x:%04x] type %02x class %#08x\n",
1876 dev->vendor, dev->device, dev->hdr_type, dev->class);
1878 /* Device class may be changed after fixup */
1879 class = dev->class >> 8;
1881 if (dev->non_compliant_bars && !dev->mmio_always_on) {
1882 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1883 if (cmd & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) {
1884 pci_info(dev, "device has non-compliant BARs; disabling IO/MEM decoding\n");
1885 cmd &= ~PCI_COMMAND_IO;
1886 cmd &= ~PCI_COMMAND_MEMORY;
1887 pci_write_config_word(dev, PCI_COMMAND, cmd);
1891 dev->broken_intx_masking = pci_intx_mask_broken(dev);
1893 switch (dev->hdr_type) { /* header type */
1894 case PCI_HEADER_TYPE_NORMAL: /* standard header */
1895 if (class == PCI_CLASS_BRIDGE_PCI)
1898 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1900 pci_subsystem_ids(dev, &dev->subsystem_vendor, &dev->subsystem_device);
1903 * Do the ugly legacy mode stuff here rather than broken chip
1904 * quirk code. Legacy mode ATA controllers have fixed
1905 * addresses. These are not always echoed in BAR0-3, and
1906 * BAR0-3 in a few cases contain junk!
1908 if (class == PCI_CLASS_STORAGE_IDE) {
1910 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1911 if ((progif & 1) == 0) {
1912 region.start = 0x1F0;
1914 res = &dev->resource[0];
1915 res->flags = LEGACY_IO_RESOURCE;
1916 pcibios_bus_to_resource(dev->bus, res, ®ion);
1917 pci_info(dev, "legacy IDE quirk: reg 0x10: %pR\n",
1919 region.start = 0x3F6;
1921 res = &dev->resource[1];
1922 res->flags = LEGACY_IO_RESOURCE;
1923 pcibios_bus_to_resource(dev->bus, res, ®ion);
1924 pci_info(dev, "legacy IDE quirk: reg 0x14: %pR\n",
1927 if ((progif & 4) == 0) {
1928 region.start = 0x170;
1930 res = &dev->resource[2];
1931 res->flags = LEGACY_IO_RESOURCE;
1932 pcibios_bus_to_resource(dev->bus, res, ®ion);
1933 pci_info(dev, "legacy IDE quirk: reg 0x18: %pR\n",
1935 region.start = 0x376;
1937 res = &dev->resource[3];
1938 res->flags = LEGACY_IO_RESOURCE;
1939 pcibios_bus_to_resource(dev->bus, res, ®ion);
1940 pci_info(dev, "legacy IDE quirk: reg 0x1c: %pR\n",
1946 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1948 * The PCI-to-PCI bridge spec requires that subtractive
1949 * decoding (i.e. transparent) bridge must have programming
1950 * interface code of 0x01.
1953 dev->transparent = ((dev->class & 0xff) == 1);
1954 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1955 pci_read_bridge_windows(dev);
1956 set_pcie_hotplug_bridge(dev);
1957 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1959 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1960 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1964 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1965 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1968 pci_read_bases(dev, 1, 0);
1969 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1970 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1973 default: /* unknown header */
1974 pci_err(dev, "unknown header type %02x, ignoring device\n",
1976 pci_release_of_node(dev);
1980 pci_err(dev, "ignoring class %#08x (doesn't match header type %02x)\n",
1981 dev->class, dev->hdr_type);
1982 dev->class = PCI_CLASS_NOT_DEFINED << 8;
1985 /* We found a fine healthy device, go go go... */
1989 static void pci_configure_mps(struct pci_dev *dev)
1991 struct pci_dev *bridge = pci_upstream_bridge(dev);
1992 int mps, mpss, p_mps, rc;
1994 if (!pci_is_pcie(dev))
1997 /* MPS and MRRS fields are of type 'RsvdP' for VFs, short-circuit out */
2002 * For Root Complex Integrated Endpoints, program the maximum
2003 * supported value unless limited by the PCIE_BUS_PEER2PEER case.
2005 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) {
2006 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
2009 mps = 128 << dev->pcie_mpss;
2010 rc = pcie_set_mps(dev, mps);
2012 pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
2018 if (!bridge || !pci_is_pcie(bridge))
2021 mps = pcie_get_mps(dev);
2022 p_mps = pcie_get_mps(bridge);
2027 if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
2028 pci_warn(dev, "Max Payload Size %d, but upstream %s set to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
2029 mps, pci_name(bridge), p_mps);
2034 * Fancier MPS configuration is done later by
2035 * pcie_bus_configure_settings()
2037 if (pcie_bus_config != PCIE_BUS_DEFAULT)
2040 mpss = 128 << dev->pcie_mpss;
2041 if (mpss < p_mps && pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT) {
2042 pcie_set_mps(bridge, mpss);
2043 pci_info(dev, "Upstream bridge's Max Payload Size set to %d (was %d, max %d)\n",
2044 mpss, p_mps, 128 << bridge->pcie_mpss);
2045 p_mps = pcie_get_mps(bridge);
2048 rc = pcie_set_mps(dev, p_mps);
2050 pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
2055 pci_info(dev, "Max Payload Size set to %d (was %d, max %d)\n",
2059 int pci_configure_extended_tags(struct pci_dev *dev, void *ign)
2061 struct pci_host_bridge *host;
2066 if (!pci_is_pcie(dev))
2069 ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap);
2073 if (!(cap & PCI_EXP_DEVCAP_EXT_TAG))
2076 ret = pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
2080 host = pci_find_host_bridge(dev->bus);
2085 * If some device in the hierarchy doesn't handle Extended Tags
2086 * correctly, make sure they're disabled.
2088 if (host->no_ext_tags) {
2089 if (ctl & PCI_EXP_DEVCTL_EXT_TAG) {
2090 pci_info(dev, "disabling Extended Tags\n");
2091 pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
2092 PCI_EXP_DEVCTL_EXT_TAG);
2097 if (!(ctl & PCI_EXP_DEVCTL_EXT_TAG)) {
2098 pci_info(dev, "enabling Extended Tags\n");
2099 pcie_capability_set_word(dev, PCI_EXP_DEVCTL,
2100 PCI_EXP_DEVCTL_EXT_TAG);
2106 * pcie_relaxed_ordering_enabled - Probe for PCIe relaxed ordering enable
2107 * @dev: PCI device to query
2109 * Returns true if the device has enabled relaxed ordering attribute.
2111 bool pcie_relaxed_ordering_enabled(struct pci_dev *dev)
2115 pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &v);
2117 return !!(v & PCI_EXP_DEVCTL_RELAX_EN);
2119 EXPORT_SYMBOL(pcie_relaxed_ordering_enabled);
2121 static void pci_configure_relaxed_ordering(struct pci_dev *dev)
2123 struct pci_dev *root;
2125 /* PCI_EXP_DEVICE_RELAX_EN is RsvdP in VFs */
2129 if (!pcie_relaxed_ordering_enabled(dev))
2133 * For now, we only deal with Relaxed Ordering issues with Root
2134 * Ports. Peer-to-Peer DMA is another can of worms.
2136 root = pcie_find_root_port(dev);
2140 if (root->dev_flags & PCI_DEV_FLAGS_NO_RELAXED_ORDERING) {
2141 pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
2142 PCI_EXP_DEVCTL_RELAX_EN);
2143 pci_info(dev, "Relaxed Ordering disabled because the Root Port didn't support it\n");
2147 static void pci_configure_ltr(struct pci_dev *dev)
2149 #ifdef CONFIG_PCIEASPM
2150 struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
2151 struct pci_dev *bridge;
2154 if (!pci_is_pcie(dev))
2157 /* Read L1 PM substate capabilities */
2158 dev->l1ss = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_L1SS);
2160 pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
2161 if (!(cap & PCI_EXP_DEVCAP2_LTR))
2164 pcie_capability_read_dword(dev, PCI_EXP_DEVCTL2, &ctl);
2165 if (ctl & PCI_EXP_DEVCTL2_LTR_EN) {
2166 if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
2171 bridge = pci_upstream_bridge(dev);
2172 if (bridge && bridge->ltr_path)
2178 if (!host->native_ltr)
2182 * Software must not enable LTR in an Endpoint unless the Root
2183 * Complex and all intermediate Switches indicate support for LTR.
2184 * PCIe r4.0, sec 6.18.
2186 if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
2187 pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
2188 PCI_EXP_DEVCTL2_LTR_EN);
2194 * If we're configuring a hot-added device, LTR was likely
2195 * disabled in the upstream bridge, so re-enable it before enabling
2196 * it in the new device.
2198 bridge = pci_upstream_bridge(dev);
2199 if (bridge && bridge->ltr_path) {
2200 pci_bridge_reconfigure_ltr(dev);
2201 pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
2202 PCI_EXP_DEVCTL2_LTR_EN);
2208 static void pci_configure_eetlp_prefix(struct pci_dev *dev)
2210 #ifdef CONFIG_PCI_PASID
2211 struct pci_dev *bridge;
2215 if (!pci_is_pcie(dev))
2218 pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
2219 if (!(cap & PCI_EXP_DEVCAP2_EE_PREFIX))
2222 pcie_type = pci_pcie_type(dev);
2223 if (pcie_type == PCI_EXP_TYPE_ROOT_PORT ||
2224 pcie_type == PCI_EXP_TYPE_RC_END)
2225 dev->eetlp_prefix_path = 1;
2227 bridge = pci_upstream_bridge(dev);
2228 if (bridge && bridge->eetlp_prefix_path)
2229 dev->eetlp_prefix_path = 1;
2234 static void pci_configure_serr(struct pci_dev *dev)
2238 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
2241 * A bridge will not forward ERR_ messages coming from an
2242 * endpoint unless SERR# forwarding is enabled.
2244 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &control);
2245 if (!(control & PCI_BRIDGE_CTL_SERR)) {
2246 control |= PCI_BRIDGE_CTL_SERR;
2247 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, control);
2252 static void pci_configure_device(struct pci_dev *dev)
2254 pci_configure_mps(dev);
2255 pci_configure_extended_tags(dev, NULL);
2256 pci_configure_relaxed_ordering(dev);
2257 pci_configure_ltr(dev);
2258 pci_configure_eetlp_prefix(dev);
2259 pci_configure_serr(dev);
2261 pci_acpi_program_hp_params(dev);
2264 static void pci_release_capabilities(struct pci_dev *dev)
2268 pci_iov_release(dev);
2269 pci_free_cap_save_buffers(dev);
2273 * pci_release_dev - Free a PCI device structure when all users of it are
2275 * @dev: device that's been disconnected
2277 * Will be called only by the device core when all users of this PCI device are
2280 static void pci_release_dev(struct device *dev)
2282 struct pci_dev *pci_dev;
2284 pci_dev = to_pci_dev(dev);
2285 pci_release_capabilities(pci_dev);
2286 pci_release_of_node(pci_dev);
2287 pcibios_release_device(pci_dev);
2288 pci_bus_put(pci_dev->bus);
2289 kfree(pci_dev->driver_override);
2290 bitmap_free(pci_dev->dma_alias_mask);
2291 dev_dbg(dev, "device released\n");
2295 struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
2297 struct pci_dev *dev;
2299 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
2303 INIT_LIST_HEAD(&dev->bus_list);
2304 dev->dev.type = &pci_dev_type;
2305 dev->bus = pci_bus_get(bus);
2306 #ifdef CONFIG_PCI_MSI
2307 raw_spin_lock_init(&dev->msi_lock);
2311 EXPORT_SYMBOL(pci_alloc_dev);
2313 static bool pci_bus_crs_vendor_id(u32 l)
2315 return (l & 0xffff) == 0x0001;
2318 static bool pci_bus_wait_crs(struct pci_bus *bus, int devfn, u32 *l,
2323 if (!pci_bus_crs_vendor_id(*l))
2324 return true; /* not a CRS completion */
2327 return false; /* CRS, but caller doesn't want to wait */
2330 * We got the reserved Vendor ID that indicates a completion with
2331 * Configuration Request Retry Status (CRS). Retry until we get a
2332 * valid Vendor ID or we time out.
2334 while (pci_bus_crs_vendor_id(*l)) {
2335 if (delay > timeout) {
2336 pr_warn("pci %04x:%02x:%02x.%d: not ready after %dms; giving up\n",
2337 pci_domain_nr(bus), bus->number,
2338 PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2343 pr_info("pci %04x:%02x:%02x.%d: not ready after %dms; waiting\n",
2344 pci_domain_nr(bus), bus->number,
2345 PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2350 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
2355 pr_info("pci %04x:%02x:%02x.%d: ready after %dms\n",
2356 pci_domain_nr(bus), bus->number,
2357 PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2362 bool pci_bus_generic_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
2365 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
2368 /* Some broken boards return 0 or ~0 (PCI_ERROR_RESPONSE) if a slot is empty: */
2369 if (PCI_POSSIBLE_ERROR(*l) || *l == 0x00000000 ||
2370 *l == 0x0000ffff || *l == 0xffff0000)
2373 if (pci_bus_crs_vendor_id(*l))
2374 return pci_bus_wait_crs(bus, devfn, l, timeout);
2379 bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
2382 #ifdef CONFIG_PCI_QUIRKS
2383 struct pci_dev *bridge = bus->self;
2386 * Certain IDT switches have an issue where they improperly trigger
2387 * ACS Source Validation errors on completions for config reads.
2389 if (bridge && bridge->vendor == PCI_VENDOR_ID_IDT &&
2390 bridge->device == 0x80b5)
2391 return pci_idt_bus_quirk(bus, devfn, l, timeout);
2394 return pci_bus_generic_read_dev_vendor_id(bus, devfn, l, timeout);
2396 EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
2399 * Read the config data for a PCI device, sanity-check it,
2400 * and fill in the dev structure.
2402 static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
2404 struct pci_dev *dev;
2407 if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
2410 dev = pci_alloc_dev(bus);
2415 dev->vendor = l & 0xffff;
2416 dev->device = (l >> 16) & 0xffff;
2418 if (pci_setup_device(dev)) {
2419 pci_bus_put(dev->bus);
2427 void pcie_report_downtraining(struct pci_dev *dev)
2429 if (!pci_is_pcie(dev))
2432 /* Look from the device up to avoid downstream ports with no devices */
2433 if ((pci_pcie_type(dev) != PCI_EXP_TYPE_ENDPOINT) &&
2434 (pci_pcie_type(dev) != PCI_EXP_TYPE_LEG_END) &&
2435 (pci_pcie_type(dev) != PCI_EXP_TYPE_UPSTREAM))
2438 /* Multi-function PCIe devices share the same link/status */
2439 if (PCI_FUNC(dev->devfn) != 0 || dev->is_virtfn)
2442 /* Print link status only if the device is constrained by the fabric */
2443 __pcie_print_link_status(dev, false);
2446 static void pci_init_capabilities(struct pci_dev *dev)
2448 pci_ea_init(dev); /* Enhanced Allocation */
2449 pci_msi_init(dev); /* Disable MSI */
2450 pci_msix_init(dev); /* Disable MSI-X */
2452 /* Buffers for saving PCIe and PCI-X capabilities */
2453 pci_allocate_cap_save_buffers(dev);
2455 pci_pm_init(dev); /* Power Management */
2456 pci_vpd_init(dev); /* Vital Product Data */
2457 pci_configure_ari(dev); /* Alternative Routing-ID Forwarding */
2458 pci_iov_init(dev); /* Single Root I/O Virtualization */
2459 pci_ats_init(dev); /* Address Translation Services */
2460 pci_pri_init(dev); /* Page Request Interface */
2461 pci_pasid_init(dev); /* Process Address Space ID */
2462 pci_acs_init(dev); /* Access Control Services */
2463 pci_ptm_init(dev); /* Precision Time Measurement */
2464 pci_aer_init(dev); /* Advanced Error Reporting */
2465 pci_dpc_init(dev); /* Downstream Port Containment */
2466 pci_rcec_init(dev); /* Root Complex Event Collector */
2468 pcie_report_downtraining(dev);
2469 pci_init_reset_methods(dev);
2473 * This is the equivalent of pci_host_bridge_msi_domain() that acts on
2474 * devices. Firmware interfaces that can select the MSI domain on a
2475 * per-device basis should be called from here.
2477 static struct irq_domain *pci_dev_msi_domain(struct pci_dev *dev)
2479 struct irq_domain *d;
2482 * If a domain has been set through the pcibios_device_add()
2483 * callback, then this is the one (platform code knows best).
2485 d = dev_get_msi_domain(&dev->dev);
2490 * Let's see if we have a firmware interface able to provide
2493 d = pci_msi_get_device_domain(dev);
2500 static void pci_set_msi_domain(struct pci_dev *dev)
2502 struct irq_domain *d;
2505 * If the platform or firmware interfaces cannot supply a
2506 * device-specific MSI domain, then inherit the default domain
2507 * from the host bridge itself.
2509 d = pci_dev_msi_domain(dev);
2511 d = dev_get_msi_domain(&dev->bus->dev);
2513 dev_set_msi_domain(&dev->dev, d);
2516 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
2520 pci_configure_device(dev);
2522 device_initialize(&dev->dev);
2523 dev->dev.release = pci_release_dev;
2525 set_dev_node(&dev->dev, pcibus_to_node(bus));
2526 dev->dev.dma_mask = &dev->dma_mask;
2527 dev->dev.dma_parms = &dev->dma_parms;
2528 dev->dev.coherent_dma_mask = 0xffffffffull;
2530 dma_set_max_seg_size(&dev->dev, 65536);
2531 dma_set_seg_boundary(&dev->dev, 0xffffffff);
2533 /* Fix up broken headers */
2534 pci_fixup_device(pci_fixup_header, dev);
2536 pci_reassigndev_resource_alignment(dev);
2538 dev->state_saved = false;
2540 pci_init_capabilities(dev);
2543 * Add the device to our list of discovered devices
2544 * and the bus list for fixup functions, etc.
2546 down_write(&pci_bus_sem);
2547 list_add_tail(&dev->bus_list, &bus->devices);
2548 up_write(&pci_bus_sem);
2550 ret = pcibios_device_add(dev);
2553 /* Set up MSI IRQ domain */
2554 pci_set_msi_domain(dev);
2556 /* Notifier could use PCI capabilities */
2557 dev->match_driver = false;
2558 ret = device_add(&dev->dev);
2562 struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn)
2564 struct pci_dev *dev;
2566 dev = pci_get_slot(bus, devfn);
2572 dev = pci_scan_device(bus, devfn);
2576 pci_device_add(dev, bus);
2580 EXPORT_SYMBOL(pci_scan_single_device);
2582 static unsigned int next_fn(struct pci_bus *bus, struct pci_dev *dev,
2587 unsigned int next_fn;
2589 if (pci_ari_enabled(bus)) {
2592 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
2596 pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap);
2597 next_fn = PCI_ARI_CAP_NFN(cap);
2599 return 0; /* protect against malformed list */
2604 /* dev may be NULL for non-contiguous multifunction devices */
2605 if (!dev || dev->multifunction)
2606 return (fn + 1) % 8;
2611 static int only_one_child(struct pci_bus *bus)
2613 struct pci_dev *bridge = bus->self;
2616 * Systems with unusual topologies set PCI_SCAN_ALL_PCIE_DEVS so
2617 * we scan for all possible devices, not just Device 0.
2619 if (pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
2623 * A PCIe Downstream Port normally leads to a Link with only Device
2624 * 0 on it (PCIe spec r3.1, sec 7.3.1). As an optimization, scan
2625 * only for Device 0 in that situation.
2627 if (bridge && pci_is_pcie(bridge) && pcie_downstream_port(bridge))
2634 * pci_scan_slot - Scan a PCI slot on a bus for devices
2635 * @bus: PCI bus to scan
2636 * @devfn: slot number to scan (must have zero function)
2638 * Scan a PCI slot on the specified PCI bus for devices, adding
2639 * discovered devices to the @bus->devices list. New devices
2640 * will not have is_added set.
2642 * Returns the number of new devices found.
2644 int pci_scan_slot(struct pci_bus *bus, int devfn)
2646 unsigned int fn, nr = 0;
2647 struct pci_dev *dev;
2649 if (only_one_child(bus) && (devfn > 0))
2650 return 0; /* Already scanned the entire slot */
2652 dev = pci_scan_single_device(bus, devfn);
2655 if (!pci_dev_is_added(dev))
2658 for (fn = next_fn(bus, dev, 0); fn > 0; fn = next_fn(bus, dev, fn)) {
2659 dev = pci_scan_single_device(bus, devfn + fn);
2661 if (!pci_dev_is_added(dev))
2663 dev->multifunction = 1;
2667 /* Only one slot has PCIe device */
2668 if (bus->self && nr)
2669 pcie_aspm_init_link_state(bus->self);
2673 EXPORT_SYMBOL(pci_scan_slot);
2675 static int pcie_find_smpss(struct pci_dev *dev, void *data)
2679 if (!pci_is_pcie(dev))
2683 * We don't have a way to change MPS settings on devices that have
2684 * drivers attached. A hot-added device might support only the minimum
2685 * MPS setting (MPS=128). Therefore, if the fabric contains a bridge
2686 * where devices may be hot-added, we limit the fabric MPS to 128 so
2687 * hot-added devices will work correctly.
2689 * However, if we hot-add a device to a slot directly below a Root
2690 * Port, it's impossible for there to be other existing devices below
2691 * the port. We don't limit the MPS in this case because we can
2692 * reconfigure MPS on both the Root Port and the hot-added device,
2693 * and there are no other devices involved.
2695 * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
2697 if (dev->is_hotplug_bridge &&
2698 pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
2701 if (*smpss > dev->pcie_mpss)
2702 *smpss = dev->pcie_mpss;
2707 static void pcie_write_mps(struct pci_dev *dev, int mps)
2711 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
2712 mps = 128 << dev->pcie_mpss;
2714 if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
2718 * For "Performance", the assumption is made that
2719 * downstream communication will never be larger than
2720 * the MRRS. So, the MPS only needs to be configured
2721 * for the upstream communication. This being the case,
2722 * walk from the top down and set the MPS of the child
2723 * to that of the parent bus.
2725 * Configure the device MPS with the smaller of the
2726 * device MPSS or the bridge MPS (which is assumed to be
2727 * properly configured at this point to the largest
2728 * allowable MPS based on its parent bus).
2730 mps = min(mps, pcie_get_mps(dev->bus->self));
2733 rc = pcie_set_mps(dev, mps);
2735 pci_err(dev, "Failed attempting to set the MPS\n");
2738 static void pcie_write_mrrs(struct pci_dev *dev)
2743 * In the "safe" case, do not configure the MRRS. There appear to be
2744 * issues with setting MRRS to 0 on a number of devices.
2746 if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
2750 * For max performance, the MRRS must be set to the largest supported
2751 * value. However, it cannot be configured larger than the MPS the
2752 * device or the bus can support. This should already be properly
2753 * configured by a prior call to pcie_write_mps().
2755 mrrs = pcie_get_mps(dev);
2758 * MRRS is a R/W register. Invalid values can be written, but a
2759 * subsequent read will verify if the value is acceptable or not.
2760 * If the MRRS value provided is not acceptable (e.g., too large),
2761 * shrink the value until it is acceptable to the HW.
2763 while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
2764 rc = pcie_set_readrq(dev, mrrs);
2768 pci_warn(dev, "Failed attempting to set the MRRS\n");
2773 pci_err(dev, "MRRS was unable to be configured with a safe value. If problems are experienced, try running with pci=pcie_bus_safe\n");
2776 static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
2780 if (!pci_is_pcie(dev))
2783 if (pcie_bus_config == PCIE_BUS_TUNE_OFF ||
2784 pcie_bus_config == PCIE_BUS_DEFAULT)
2787 mps = 128 << *(u8 *)data;
2788 orig_mps = pcie_get_mps(dev);
2790 pcie_write_mps(dev, mps);
2791 pcie_write_mrrs(dev);
2793 pci_info(dev, "Max Payload Size set to %4d/%4d (was %4d), Max Read Rq %4d\n",
2794 pcie_get_mps(dev), 128 << dev->pcie_mpss,
2795 orig_mps, pcie_get_readrq(dev));
2801 * pcie_bus_configure_settings() requires that pci_walk_bus work in a top-down,
2802 * parents then children fashion. If this changes, then this code will not
2805 void pcie_bus_configure_settings(struct pci_bus *bus)
2812 if (!pci_is_pcie(bus->self))
2816 * FIXME - Peer to peer DMA is possible, though the endpoint would need
2817 * to be aware of the MPS of the destination. To work around this,
2818 * simply force the MPS of the entire system to the smallest possible.
2820 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
2823 if (pcie_bus_config == PCIE_BUS_SAFE) {
2824 smpss = bus->self->pcie_mpss;
2826 pcie_find_smpss(bus->self, &smpss);
2827 pci_walk_bus(bus, pcie_find_smpss, &smpss);
2830 pcie_bus_configure_set(bus->self, &smpss);
2831 pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
2833 EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
2836 * Called after each bus is probed, but before its children are examined. This
2837 * is marked as __weak because multiple architectures define it.
2839 void __weak pcibios_fixup_bus(struct pci_bus *bus)
2841 /* nothing to do, expected to be removed in the future */
2845 * pci_scan_child_bus_extend() - Scan devices below a bus
2846 * @bus: Bus to scan for devices
2847 * @available_buses: Total number of buses available (%0 does not try to
2848 * extend beyond the minimal)
2850 * Scans devices below @bus including subordinate buses. Returns new
2851 * subordinate number including all the found devices. Passing
2852 * @available_buses causes the remaining bus space to be distributed
2853 * equally between hotplug-capable bridges to allow future extension of the
2856 static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
2857 unsigned int available_buses)
2859 unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0;
2860 unsigned int start = bus->busn_res.start;
2861 unsigned int devfn, fn, cmax, max = start;
2862 struct pci_dev *dev;
2865 dev_dbg(&bus->dev, "scanning bus\n");
2867 /* Go find them, Rover! */
2868 for (devfn = 0; devfn < 256; devfn += 8) {
2869 nr_devs = pci_scan_slot(bus, devfn);
2872 * The Jailhouse hypervisor may pass individual functions of a
2873 * multi-function device to a guest without passing function 0.
2874 * Look for them as well.
2876 if (jailhouse_paravirt() && nr_devs == 0) {
2877 for (fn = 1; fn < 8; fn++) {
2878 dev = pci_scan_single_device(bus, devfn + fn);
2880 dev->multifunction = 1;
2885 /* Reserve buses for SR-IOV capability */
2886 used_buses = pci_iov_bus_range(bus);
2890 * After performing arch-dependent fixup of the bus, look behind
2891 * all PCI-to-PCI bridges on this bus.
2893 if (!bus->is_added) {
2894 dev_dbg(&bus->dev, "fixups for bus\n");
2895 pcibios_fixup_bus(bus);
2900 * Calculate how many hotplug bridges and normal bridges there
2901 * are on this bus. We will distribute the additional available
2902 * buses between hotplug bridges.
2904 for_each_pci_bridge(dev, bus) {
2905 if (dev->is_hotplug_bridge)
2912 * Scan bridges that are already configured. We don't touch them
2913 * unless they are misconfigured (which will be done in the second
2916 for_each_pci_bridge(dev, bus) {
2918 max = pci_scan_bridge_extend(bus, dev, max, 0, 0);
2921 * Reserve one bus for each bridge now to avoid extending
2922 * hotplug bridges too much during the second scan below.
2926 used_buses += cmax - max - 1;
2929 /* Scan bridges that need to be reconfigured */
2930 for_each_pci_bridge(dev, bus) {
2931 unsigned int buses = 0;
2933 if (!hotplug_bridges && normal_bridges == 1) {
2936 * There is only one bridge on the bus (upstream
2937 * port) so it gets all available buses which it
2938 * can then distribute to the possible hotplug
2941 buses = available_buses;
2942 } else if (dev->is_hotplug_bridge) {
2945 * Distribute the extra buses between hotplug
2948 buses = available_buses / hotplug_bridges;
2949 buses = min(buses, available_buses - used_buses + 1);
2953 max = pci_scan_bridge_extend(bus, dev, cmax, buses, 1);
2954 /* One bus is already accounted so don't add it again */
2956 used_buses += max - cmax - 1;
2960 * Make sure a hotplug bridge has at least the minimum requested
2961 * number of buses but allow it to grow up to the maximum available
2962 * bus number of there is room.
2964 if (bus->self && bus->self->is_hotplug_bridge) {
2965 used_buses = max_t(unsigned int, available_buses,
2966 pci_hotplug_bus_size - 1);
2967 if (max - start < used_buses) {
2968 max = start + used_buses;
2970 /* Do not allocate more buses than we have room left */
2971 if (max > bus->busn_res.end)
2972 max = bus->busn_res.end;
2974 dev_dbg(&bus->dev, "%pR extended by %#02x\n",
2975 &bus->busn_res, max - start);
2980 * We've scanned the bus and so we know all about what's on
2981 * the other side of any bridges that may be on this bus plus
2984 * Return how far we've got finding sub-buses.
2986 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
2991 * pci_scan_child_bus() - Scan devices below a bus
2992 * @bus: Bus to scan for devices
2994 * Scans devices below @bus including subordinate buses. Returns new
2995 * subordinate number including all the found devices.
2997 unsigned int pci_scan_child_bus(struct pci_bus *bus)
2999 return pci_scan_child_bus_extend(bus, 0);
3001 EXPORT_SYMBOL_GPL(pci_scan_child_bus);
3004 * pcibios_root_bridge_prepare - Platform-specific host bridge setup
3005 * @bridge: Host bridge to set up
3007 * Default empty implementation. Replace with an architecture-specific setup
3008 * routine, if necessary.
3010 int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
3015 void __weak pcibios_add_bus(struct pci_bus *bus)
3019 void __weak pcibios_remove_bus(struct pci_bus *bus)
3023 struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
3024 struct pci_ops *ops, void *sysdata, struct list_head *resources)
3027 struct pci_host_bridge *bridge;
3029 bridge = pci_alloc_host_bridge(0);
3033 bridge->dev.parent = parent;
3035 list_splice_init(resources, &bridge->windows);
3036 bridge->sysdata = sysdata;
3037 bridge->busnr = bus;
3040 error = pci_register_host_bridge(bridge);
3047 put_device(&bridge->dev);
3050 EXPORT_SYMBOL_GPL(pci_create_root_bus);
3052 int pci_host_probe(struct pci_host_bridge *bridge)
3054 struct pci_bus *bus, *child;
3057 ret = pci_scan_root_bus_bridge(bridge);
3059 dev_err(bridge->dev.parent, "Scanning root bridge failed");
3066 * We insert PCI resources into the iomem_resource and
3067 * ioport_resource trees in either pci_bus_claim_resources()
3068 * or pci_bus_assign_resources().
3070 if (pci_has_flag(PCI_PROBE_ONLY)) {
3071 pci_bus_claim_resources(bus);
3073 pci_bus_size_bridges(bus);
3074 pci_bus_assign_resources(bus);
3076 list_for_each_entry(child, &bus->children, node)
3077 pcie_bus_configure_settings(child);
3080 pci_bus_add_devices(bus);
3083 EXPORT_SYMBOL_GPL(pci_host_probe);
3085 int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
3087 struct resource *res = &b->busn_res;
3088 struct resource *parent_res, *conflict;
3092 res->flags = IORESOURCE_BUS;
3094 if (!pci_is_root_bus(b))
3095 parent_res = &b->parent->busn_res;
3097 parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
3098 res->flags |= IORESOURCE_PCI_FIXED;
3101 conflict = request_resource_conflict(parent_res, res);
3105 "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
3106 res, pci_is_root_bus(b) ? "domain " : "",
3107 parent_res, conflict->name, conflict);
3109 return conflict == NULL;
3112 int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
3114 struct resource *res = &b->busn_res;
3115 struct resource old_res = *res;
3116 resource_size_t size;
3119 if (res->start > bus_max)
3122 size = bus_max - res->start + 1;
3123 ret = adjust_resource(res, res->start, size);
3124 dev_info(&b->dev, "busn_res: %pR end %s updated to %02x\n",
3125 &old_res, ret ? "can not be" : "is", bus_max);
3127 if (!ret && !res->parent)
3128 pci_bus_insert_busn_res(b, res->start, res->end);
3133 void pci_bus_release_busn_res(struct pci_bus *b)
3135 struct resource *res = &b->busn_res;
3138 if (!res->flags || !res->parent)
3141 ret = release_resource(res);
3142 dev_info(&b->dev, "busn_res: %pR %s released\n",
3143 res, ret ? "can not be" : "is");
3146 int pci_scan_root_bus_bridge(struct pci_host_bridge *bridge)
3148 struct resource_entry *window;
3156 resource_list_for_each_entry(window, &bridge->windows)
3157 if (window->res->flags & IORESOURCE_BUS) {
3158 bridge->busnr = window->res->start;
3163 ret = pci_register_host_bridge(bridge);
3168 bus = bridge->busnr;
3172 "No busn resource found for root bus, will use [bus %02x-ff]\n",
3174 pci_bus_insert_busn_res(b, bus, 255);
3177 max = pci_scan_child_bus(b);
3180 pci_bus_update_busn_res_end(b, max);
3184 EXPORT_SYMBOL(pci_scan_root_bus_bridge);
3186 struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
3187 struct pci_ops *ops, void *sysdata, struct list_head *resources)
3189 struct resource_entry *window;
3194 resource_list_for_each_entry(window, resources)
3195 if (window->res->flags & IORESOURCE_BUS) {
3200 b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
3206 "No busn resource found for root bus, will use [bus %02x-ff]\n",
3208 pci_bus_insert_busn_res(b, bus, 255);
3211 max = pci_scan_child_bus(b);
3214 pci_bus_update_busn_res_end(b, max);
3218 EXPORT_SYMBOL(pci_scan_root_bus);
3220 struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
3223 LIST_HEAD(resources);
3226 pci_add_resource(&resources, &ioport_resource);
3227 pci_add_resource(&resources, &iomem_resource);
3228 pci_add_resource(&resources, &busn_resource);
3229 b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
3231 pci_scan_child_bus(b);
3233 pci_free_resource_list(&resources);
3237 EXPORT_SYMBOL(pci_scan_bus);
3240 * pci_rescan_bus_bridge_resize - Scan a PCI bus for devices
3241 * @bridge: PCI bridge for the bus to scan
3243 * Scan a PCI bus and child buses for new devices, add them,
3244 * and enable them, resizing bridge mmio/io resource if necessary
3245 * and possible. The caller must ensure the child devices are already
3246 * removed for resizing to occur.
3248 * Returns the max number of subordinate bus discovered.
3250 unsigned int pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
3253 struct pci_bus *bus = bridge->subordinate;
3255 max = pci_scan_child_bus(bus);
3257 pci_assign_unassigned_bridge_resources(bridge);
3259 pci_bus_add_devices(bus);
3265 * pci_rescan_bus - Scan a PCI bus for devices
3266 * @bus: PCI bus to scan
3268 * Scan a PCI bus and child buses for new devices, add them,
3271 * Returns the max number of subordinate bus discovered.
3273 unsigned int pci_rescan_bus(struct pci_bus *bus)
3277 max = pci_scan_child_bus(bus);
3278 pci_assign_unassigned_bus_resources(bus);
3279 pci_bus_add_devices(bus);
3283 EXPORT_SYMBOL_GPL(pci_rescan_bus);
3286 * pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal
3287 * routines should always be executed under this mutex.
3289 static DEFINE_MUTEX(pci_rescan_remove_lock);
3291 void pci_lock_rescan_remove(void)
3293 mutex_lock(&pci_rescan_remove_lock);
3295 EXPORT_SYMBOL_GPL(pci_lock_rescan_remove);
3297 void pci_unlock_rescan_remove(void)
3299 mutex_unlock(&pci_rescan_remove_lock);
3301 EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove);
3303 static int __init pci_sort_bf_cmp(const struct device *d_a,
3304 const struct device *d_b)
3306 const struct pci_dev *a = to_pci_dev(d_a);
3307 const struct pci_dev *b = to_pci_dev(d_b);
3309 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
3310 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
3312 if (a->bus->number < b->bus->number) return -1;
3313 else if (a->bus->number > b->bus->number) return 1;
3315 if (a->devfn < b->devfn) return -1;
3316 else if (a->devfn > b->devfn) return 1;
3321 void __init pci_sort_breadthfirst(void)
3323 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);
3326 int pci_hp_add_bridge(struct pci_dev *dev)
3328 struct pci_bus *parent = dev->bus;
3329 int busnr, start = parent->busn_res.start;
3330 unsigned int available_buses = 0;
3331 int end = parent->busn_res.end;
3333 for (busnr = start; busnr <= end; busnr++) {
3334 if (!pci_find_bus(pci_domain_nr(parent), busnr))
3337 if (busnr-- > end) {
3338 pci_err(dev, "No bus number available for hot-added bridge\n");
3342 /* Scan bridges that are already configured */
3343 busnr = pci_scan_bridge(parent, dev, busnr, 0);
3346 * Distribute the available bus numbers between hotplug-capable
3347 * bridges to make extending the chain later possible.
3349 available_buses = end - busnr;
3351 /* Scan bridges that need to be reconfigured */
3352 pci_scan_bridge_extend(parent, dev, busnr, available_buses, 1);
3354 if (!dev->subordinate)
3359 EXPORT_SYMBOL_GPL(pci_hp_add_bridge);