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/of_device.h>
11 #include <linux/of_pci.h>
12 #include <linux/pci_hotplug.h>
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <linux/cpumask.h>
16 #include <linux/aer.h>
17 #include <linux/acpi.h>
18 #include <linux/hypervisor.h>
19 #include <linux/irqdomain.h>
20 #include <linux/pm_runtime.h>
23 #define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
24 #define CARDBUS_RESERVE_BUSNR 3
26 static struct resource busn_resource = {
30 .flags = IORESOURCE_BUS,
33 /* Ugh. Need to stop exporting this to modules. */
34 LIST_HEAD(pci_root_buses);
35 EXPORT_SYMBOL(pci_root_buses);
37 static LIST_HEAD(pci_domain_busn_res_list);
39 struct pci_domain_busn_res {
40 struct list_head list;
45 static struct resource *get_pci_domain_busn_res(int domain_nr)
47 struct pci_domain_busn_res *r;
49 list_for_each_entry(r, &pci_domain_busn_res_list, list)
50 if (r->domain_nr == domain_nr)
53 r = kzalloc(sizeof(*r), GFP_KERNEL);
57 r->domain_nr = domain_nr;
60 r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
62 list_add_tail(&r->list, &pci_domain_busn_res_list);
67 static int find_anything(struct device *dev, void *data)
73 * Some device drivers need know if PCI is initiated.
74 * Basically, we think PCI is not initiated when there
75 * is no device to be found on the pci_bus_type.
77 int no_pci_devices(void)
82 dev = bus_find_device(&pci_bus_type, NULL, NULL, find_anything);
83 no_devices = (dev == NULL);
87 EXPORT_SYMBOL(no_pci_devices);
92 static void release_pcibus_dev(struct device *dev)
94 struct pci_bus *pci_bus = to_pci_bus(dev);
96 put_device(pci_bus->bridge);
97 pci_bus_remove_resources(pci_bus);
98 pci_release_bus_of_node(pci_bus);
102 static struct class pcibus_class = {
104 .dev_release = &release_pcibus_dev,
105 .dev_groups = pcibus_groups,
108 static int __init pcibus_class_init(void)
110 return class_register(&pcibus_class);
112 postcore_initcall(pcibus_class_init);
114 static u64 pci_size(u64 base, u64 maxbase, u64 mask)
116 u64 size = mask & maxbase; /* Find the significant bits */
121 * Get the lowest of them to find the decode size, and from that
124 size = size & ~(size-1);
127 * base == maxbase can be valid only if the BAR has already been
128 * programmed with all 1s.
130 if (base == maxbase && ((base | (size - 1)) & mask) != mask)
136 static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
141 if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
142 flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
143 flags |= IORESOURCE_IO;
147 flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
148 flags |= IORESOURCE_MEM;
149 if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
150 flags |= IORESOURCE_PREFETCH;
152 mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
154 case PCI_BASE_ADDRESS_MEM_TYPE_32:
156 case PCI_BASE_ADDRESS_MEM_TYPE_1M:
157 /* 1M mem BAR treated as 32-bit BAR */
159 case PCI_BASE_ADDRESS_MEM_TYPE_64:
160 flags |= IORESOURCE_MEM_64;
163 /* mem unknown type treated as 32-bit BAR */
169 #define PCI_COMMAND_DECODE_ENABLE (PCI_COMMAND_MEMORY | PCI_COMMAND_IO)
172 * pci_read_base - Read a PCI BAR
173 * @dev: the PCI device
174 * @type: type of the BAR
175 * @res: resource buffer to be filled in
176 * @pos: BAR position in the config space
178 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
180 int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
181 struct resource *res, unsigned int pos)
183 u32 l = 0, sz = 0, mask;
184 u64 l64, sz64, mask64;
186 struct pci_bus_region region, inverted_region;
188 mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
190 /* No printks while decoding is disabled! */
191 if (!dev->mmio_always_on) {
192 pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
193 if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) {
194 pci_write_config_word(dev, PCI_COMMAND,
195 orig_cmd & ~PCI_COMMAND_DECODE_ENABLE);
199 res->name = pci_name(dev);
201 pci_read_config_dword(dev, pos, &l);
202 pci_write_config_dword(dev, pos, l | mask);
203 pci_read_config_dword(dev, pos, &sz);
204 pci_write_config_dword(dev, pos, l);
207 * All bits set in sz means the device isn't working properly.
208 * If the BAR isn't implemented, all bits must be 0. If it's a
209 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
212 if (sz == 0xffffffff)
216 * I don't know how l can have all bits set. Copied from old code.
217 * Maybe it fixes a bug on some ancient platform.
222 if (type == pci_bar_unknown) {
223 res->flags = decode_bar(dev, l);
224 res->flags |= IORESOURCE_SIZEALIGN;
225 if (res->flags & IORESOURCE_IO) {
226 l64 = l & PCI_BASE_ADDRESS_IO_MASK;
227 sz64 = sz & PCI_BASE_ADDRESS_IO_MASK;
228 mask64 = PCI_BASE_ADDRESS_IO_MASK & (u32)IO_SPACE_LIMIT;
230 l64 = l & PCI_BASE_ADDRESS_MEM_MASK;
231 sz64 = sz & PCI_BASE_ADDRESS_MEM_MASK;
232 mask64 = (u32)PCI_BASE_ADDRESS_MEM_MASK;
235 if (l & PCI_ROM_ADDRESS_ENABLE)
236 res->flags |= IORESOURCE_ROM_ENABLE;
237 l64 = l & PCI_ROM_ADDRESS_MASK;
238 sz64 = sz & PCI_ROM_ADDRESS_MASK;
239 mask64 = PCI_ROM_ADDRESS_MASK;
242 if (res->flags & IORESOURCE_MEM_64) {
243 pci_read_config_dword(dev, pos + 4, &l);
244 pci_write_config_dword(dev, pos + 4, ~0);
245 pci_read_config_dword(dev, pos + 4, &sz);
246 pci_write_config_dword(dev, pos + 4, l);
248 l64 |= ((u64)l << 32);
249 sz64 |= ((u64)sz << 32);
250 mask64 |= ((u64)~0 << 32);
253 if (!dev->mmio_always_on && (orig_cmd & PCI_COMMAND_DECODE_ENABLE))
254 pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
259 sz64 = pci_size(l64, sz64, mask64);
261 pci_info(dev, FW_BUG "reg 0x%x: invalid BAR (can't size)\n",
266 if (res->flags & IORESOURCE_MEM_64) {
267 if ((sizeof(pci_bus_addr_t) < 8 || sizeof(resource_size_t) < 8)
268 && sz64 > 0x100000000ULL) {
269 res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
272 pci_err(dev, "reg 0x%x: can't handle BAR larger than 4GB (size %#010llx)\n",
273 pos, (unsigned long long)sz64);
277 if ((sizeof(pci_bus_addr_t) < 8) && l) {
278 /* Above 32-bit boundary; try to reallocate */
279 res->flags |= IORESOURCE_UNSET;
282 pci_info(dev, "reg 0x%x: can't handle BAR above 4GB (bus address %#010llx)\n",
283 pos, (unsigned long long)l64);
289 region.end = l64 + sz64 - 1;
291 pcibios_bus_to_resource(dev->bus, res, ®ion);
292 pcibios_resource_to_bus(dev->bus, &inverted_region, res);
295 * If "A" is a BAR value (a bus address), "bus_to_resource(A)" is
296 * the corresponding resource address (the physical address used by
297 * the CPU. Converting that resource address back to a bus address
298 * should yield the original BAR value:
300 * resource_to_bus(bus_to_resource(A)) == A
302 * If it doesn't, CPU accesses to "bus_to_resource(A)" will not
303 * be claimed by the device.
305 if (inverted_region.start != region.start) {
306 res->flags |= IORESOURCE_UNSET;
308 res->end = region.end - region.start;
309 pci_info(dev, "reg 0x%x: initial BAR value %#010llx invalid\n",
310 pos, (unsigned long long)region.start);
320 pci_info(dev, "reg 0x%x: %pR\n", pos, res);
322 return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
325 static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
327 unsigned int pos, reg;
329 if (dev->non_compliant_bars)
332 /* Per PCIe r4.0, sec 9.3.4.1.11, the VF BARs are all RO Zero */
336 for (pos = 0; pos < howmany; pos++) {
337 struct resource *res = &dev->resource[pos];
338 reg = PCI_BASE_ADDRESS_0 + (pos << 2);
339 pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
343 struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
344 dev->rom_base_reg = rom;
345 res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
346 IORESOURCE_READONLY | IORESOURCE_SIZEALIGN;
347 __pci_read_base(dev, pci_bar_mem32, res, rom);
351 static void pci_read_bridge_windows(struct pci_dev *bridge)
356 pci_read_config_word(bridge, PCI_IO_BASE, &io);
358 pci_write_config_word(bridge, PCI_IO_BASE, 0xe0f0);
359 pci_read_config_word(bridge, PCI_IO_BASE, &io);
360 pci_write_config_word(bridge, PCI_IO_BASE, 0x0);
363 bridge->io_window = 1;
366 * DECchip 21050 pass 2 errata: the bridge may miss an address
367 * disconnect boundary by one PCI data phase. Workaround: do not
368 * use prefetching on this device.
370 if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001)
373 pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
375 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE,
377 pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
378 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0);
383 bridge->pref_window = 1;
385 if ((pmem & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
388 * Bridge claims to have a 64-bit prefetchable memory
389 * window; verify that the upper bits are actually
392 pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &pmem);
393 pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32,
395 pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &tmp);
396 pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, pmem);
398 bridge->pref_64_window = 1;
402 static void pci_read_bridge_io(struct pci_bus *child)
404 struct pci_dev *dev = child->self;
405 u8 io_base_lo, io_limit_lo;
406 unsigned long io_mask, io_granularity, base, limit;
407 struct pci_bus_region region;
408 struct resource *res;
410 io_mask = PCI_IO_RANGE_MASK;
411 io_granularity = 0x1000;
412 if (dev->io_window_1k) {
413 /* Support 1K I/O space granularity */
414 io_mask = PCI_IO_1K_RANGE_MASK;
415 io_granularity = 0x400;
418 res = child->resource[0];
419 pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
420 pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
421 base = (io_base_lo & io_mask) << 8;
422 limit = (io_limit_lo & io_mask) << 8;
424 if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
425 u16 io_base_hi, io_limit_hi;
427 pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
428 pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
429 base |= ((unsigned long) io_base_hi << 16);
430 limit |= ((unsigned long) io_limit_hi << 16);
434 res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
436 region.end = limit + io_granularity - 1;
437 pcibios_bus_to_resource(dev->bus, res, ®ion);
438 pci_info(dev, " bridge window %pR\n", res);
442 static void pci_read_bridge_mmio(struct pci_bus *child)
444 struct pci_dev *dev = child->self;
445 u16 mem_base_lo, mem_limit_lo;
446 unsigned long base, limit;
447 struct pci_bus_region region;
448 struct resource *res;
450 res = child->resource[1];
451 pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
452 pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
453 base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
454 limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
456 res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
458 region.end = limit + 0xfffff;
459 pcibios_bus_to_resource(dev->bus, res, ®ion);
460 pci_info(dev, " bridge window %pR\n", res);
464 static void pci_read_bridge_mmio_pref(struct pci_bus *child)
466 struct pci_dev *dev = child->self;
467 u16 mem_base_lo, mem_limit_lo;
469 pci_bus_addr_t base, limit;
470 struct pci_bus_region region;
471 struct resource *res;
473 res = child->resource[2];
474 pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
475 pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
476 base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
477 limit64 = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
479 if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
480 u32 mem_base_hi, mem_limit_hi;
482 pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
483 pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
486 * Some bridges set the base > limit by default, and some
487 * (broken) BIOSes do not initialize them. If we find
488 * this, just assume they are not being used.
490 if (mem_base_hi <= mem_limit_hi) {
491 base64 |= (u64) mem_base_hi << 32;
492 limit64 |= (u64) mem_limit_hi << 32;
496 base = (pci_bus_addr_t) base64;
497 limit = (pci_bus_addr_t) limit64;
499 if (base != base64) {
500 pci_err(dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
501 (unsigned long long) base64);
506 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
507 IORESOURCE_MEM | IORESOURCE_PREFETCH;
508 if (res->flags & PCI_PREF_RANGE_TYPE_64)
509 res->flags |= IORESOURCE_MEM_64;
511 region.end = limit + 0xfffff;
512 pcibios_bus_to_resource(dev->bus, res, ®ion);
513 pci_info(dev, " bridge window %pR\n", res);
517 void pci_read_bridge_bases(struct pci_bus *child)
519 struct pci_dev *dev = child->self;
520 struct resource *res;
523 if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
526 pci_info(dev, "PCI bridge to %pR%s\n",
528 dev->transparent ? " (subtractive decode)" : "");
530 pci_bus_remove_resources(child);
531 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
532 child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
534 pci_read_bridge_io(child);
535 pci_read_bridge_mmio(child);
536 pci_read_bridge_mmio_pref(child);
538 if (dev->transparent) {
539 pci_bus_for_each_resource(child->parent, res, i) {
540 if (res && res->flags) {
541 pci_bus_add_resource(child, res,
542 PCI_SUBTRACTIVE_DECODE);
543 pci_info(dev, " bridge window %pR (subtractive decode)\n",
550 static struct pci_bus *pci_alloc_bus(struct pci_bus *parent)
554 b = kzalloc(sizeof(*b), GFP_KERNEL);
558 INIT_LIST_HEAD(&b->node);
559 INIT_LIST_HEAD(&b->children);
560 INIT_LIST_HEAD(&b->devices);
561 INIT_LIST_HEAD(&b->slots);
562 INIT_LIST_HEAD(&b->resources);
563 b->max_bus_speed = PCI_SPEED_UNKNOWN;
564 b->cur_bus_speed = PCI_SPEED_UNKNOWN;
565 #ifdef CONFIG_PCI_DOMAINS_GENERIC
567 b->domain_nr = parent->domain_nr;
572 static void devm_pci_release_host_bridge_dev(struct device *dev)
574 struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
576 if (bridge->release_fn)
577 bridge->release_fn(bridge);
579 pci_free_resource_list(&bridge->windows);
582 static void pci_release_host_bridge_dev(struct device *dev)
584 devm_pci_release_host_bridge_dev(dev);
585 kfree(to_pci_host_bridge(dev));
588 static void pci_init_host_bridge(struct pci_host_bridge *bridge)
590 INIT_LIST_HEAD(&bridge->windows);
591 INIT_LIST_HEAD(&bridge->dma_ranges);
594 * We assume we can manage these PCIe features. Some systems may
595 * reserve these for use by the platform itself, e.g., an ACPI BIOS
596 * may implement its own AER handling and use _OSC to prevent the
597 * OS from interfering.
599 bridge->native_aer = 1;
600 bridge->native_pcie_hotplug = 1;
601 bridge->native_shpc_hotplug = 1;
602 bridge->native_pme = 1;
603 bridge->native_ltr = 1;
606 struct pci_host_bridge *pci_alloc_host_bridge(size_t priv)
608 struct pci_host_bridge *bridge;
610 bridge = kzalloc(sizeof(*bridge) + priv, GFP_KERNEL);
614 pci_init_host_bridge(bridge);
615 bridge->dev.release = pci_release_host_bridge_dev;
619 EXPORT_SYMBOL(pci_alloc_host_bridge);
621 struct pci_host_bridge *devm_pci_alloc_host_bridge(struct device *dev,
624 struct pci_host_bridge *bridge;
626 bridge = devm_kzalloc(dev, sizeof(*bridge) + priv, GFP_KERNEL);
630 pci_init_host_bridge(bridge);
631 bridge->dev.release = devm_pci_release_host_bridge_dev;
635 EXPORT_SYMBOL(devm_pci_alloc_host_bridge);
637 void pci_free_host_bridge(struct pci_host_bridge *bridge)
639 pci_free_resource_list(&bridge->windows);
640 pci_free_resource_list(&bridge->dma_ranges);
644 EXPORT_SYMBOL(pci_free_host_bridge);
646 static const unsigned char pcix_bus_speed[] = {
647 PCI_SPEED_UNKNOWN, /* 0 */
648 PCI_SPEED_66MHz_PCIX, /* 1 */
649 PCI_SPEED_100MHz_PCIX, /* 2 */
650 PCI_SPEED_133MHz_PCIX, /* 3 */
651 PCI_SPEED_UNKNOWN, /* 4 */
652 PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
653 PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
654 PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
655 PCI_SPEED_UNKNOWN, /* 8 */
656 PCI_SPEED_66MHz_PCIX_266, /* 9 */
657 PCI_SPEED_100MHz_PCIX_266, /* A */
658 PCI_SPEED_133MHz_PCIX_266, /* B */
659 PCI_SPEED_UNKNOWN, /* C */
660 PCI_SPEED_66MHz_PCIX_533, /* D */
661 PCI_SPEED_100MHz_PCIX_533, /* E */
662 PCI_SPEED_133MHz_PCIX_533 /* F */
665 const unsigned char pcie_link_speed[] = {
666 PCI_SPEED_UNKNOWN, /* 0 */
667 PCIE_SPEED_2_5GT, /* 1 */
668 PCIE_SPEED_5_0GT, /* 2 */
669 PCIE_SPEED_8_0GT, /* 3 */
670 PCIE_SPEED_16_0GT, /* 4 */
671 PCI_SPEED_UNKNOWN, /* 5 */
672 PCI_SPEED_UNKNOWN, /* 6 */
673 PCI_SPEED_UNKNOWN, /* 7 */
674 PCI_SPEED_UNKNOWN, /* 8 */
675 PCI_SPEED_UNKNOWN, /* 9 */
676 PCI_SPEED_UNKNOWN, /* A */
677 PCI_SPEED_UNKNOWN, /* B */
678 PCI_SPEED_UNKNOWN, /* C */
679 PCI_SPEED_UNKNOWN, /* D */
680 PCI_SPEED_UNKNOWN, /* E */
681 PCI_SPEED_UNKNOWN /* F */
684 void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
686 bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS];
688 EXPORT_SYMBOL_GPL(pcie_update_link_speed);
690 static unsigned char agp_speeds[] = {
698 static enum pci_bus_speed agp_speed(int agp3, int agpstat)
704 else if (agpstat & 2)
706 else if (agpstat & 1)
718 return agp_speeds[index];
721 static void pci_set_bus_speed(struct pci_bus *bus)
723 struct pci_dev *bridge = bus->self;
726 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
728 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
732 pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
733 bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
735 pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
736 bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
739 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
742 enum pci_bus_speed max;
744 pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
747 if (status & PCI_X_SSTATUS_533MHZ) {
748 max = PCI_SPEED_133MHz_PCIX_533;
749 } else if (status & PCI_X_SSTATUS_266MHZ) {
750 max = PCI_SPEED_133MHz_PCIX_266;
751 } else if (status & PCI_X_SSTATUS_133MHZ) {
752 if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2)
753 max = PCI_SPEED_133MHz_PCIX_ECC;
755 max = PCI_SPEED_133MHz_PCIX;
757 max = PCI_SPEED_66MHz_PCIX;
760 bus->max_bus_speed = max;
761 bus->cur_bus_speed = pcix_bus_speed[
762 (status & PCI_X_SSTATUS_FREQ) >> 6];
767 if (pci_is_pcie(bridge)) {
771 pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
772 bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
773 bridge->link_active_reporting = !!(linkcap & PCI_EXP_LNKCAP_DLLLARC);
775 pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
776 pcie_update_link_speed(bus, linksta);
780 static struct irq_domain *pci_host_bridge_msi_domain(struct pci_bus *bus)
782 struct irq_domain *d;
785 * Any firmware interface that can resolve the msi_domain
786 * should be called from here.
788 d = pci_host_bridge_of_msi_domain(bus);
790 d = pci_host_bridge_acpi_msi_domain(bus);
792 #ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
794 * If no IRQ domain was found via the OF tree, try looking it up
795 * directly through the fwnode_handle.
798 struct fwnode_handle *fwnode = pci_root_bus_fwnode(bus);
801 d = irq_find_matching_fwnode(fwnode,
809 static void pci_set_bus_msi_domain(struct pci_bus *bus)
811 struct irq_domain *d;
815 * The bus can be a root bus, a subordinate bus, or a virtual bus
816 * created by an SR-IOV device. Walk up to the first bridge device
817 * found or derive the domain from the host bridge.
819 for (b = bus, d = NULL; !d && !pci_is_root_bus(b); b = b->parent) {
821 d = dev_get_msi_domain(&b->self->dev);
825 d = pci_host_bridge_msi_domain(b);
827 dev_set_msi_domain(&bus->dev, d);
830 static int pci_register_host_bridge(struct pci_host_bridge *bridge)
832 struct device *parent = bridge->dev.parent;
833 struct resource_entry *window, *n;
834 struct pci_bus *bus, *b;
835 resource_size_t offset;
836 LIST_HEAD(resources);
837 struct resource *res;
842 bus = pci_alloc_bus(NULL);
848 /* Temporarily move resources off the list */
849 list_splice_init(&bridge->windows, &resources);
850 bus->sysdata = bridge->sysdata;
851 bus->msi = bridge->msi;
852 bus->ops = bridge->ops;
853 bus->number = bus->busn_res.start = bridge->busnr;
854 #ifdef CONFIG_PCI_DOMAINS_GENERIC
855 bus->domain_nr = pci_bus_find_domain_nr(bus, parent);
858 b = pci_find_bus(pci_domain_nr(bus), bridge->busnr);
860 /* Ignore it if we already got here via a different bridge */
861 dev_dbg(&b->dev, "bus already known\n");
866 dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(bus),
869 err = pcibios_root_bridge_prepare(bridge);
873 err = device_register(&bridge->dev);
875 put_device(&bridge->dev);
877 bus->bridge = get_device(&bridge->dev);
878 device_enable_async_suspend(bus->bridge);
879 pci_set_bus_of_node(bus);
880 pci_set_bus_msi_domain(bus);
883 set_dev_node(bus->bridge, pcibus_to_node(bus));
885 bus->dev.class = &pcibus_class;
886 bus->dev.parent = bus->bridge;
888 dev_set_name(&bus->dev, "%04x:%02x", pci_domain_nr(bus), bus->number);
889 name = dev_name(&bus->dev);
891 err = device_register(&bus->dev);
895 pcibios_add_bus(bus);
897 /* Create legacy_io and legacy_mem files for this bus */
898 pci_create_legacy_files(bus);
901 dev_info(parent, "PCI host bridge to bus %s\n", name);
903 pr_info("PCI host bridge to bus %s\n", name);
905 /* Add initial resources to the bus */
906 resource_list_for_each_entry_safe(window, n, &resources) {
907 list_move_tail(&window->node, &bridge->windows);
908 offset = window->offset;
911 if (res->flags & IORESOURCE_BUS)
912 pci_bus_insert_busn_res(bus, bus->number, res->end);
914 pci_bus_add_resource(bus, res, 0);
917 if (resource_type(res) == IORESOURCE_IO)
918 fmt = " (bus address [%#06llx-%#06llx])";
920 fmt = " (bus address [%#010llx-%#010llx])";
922 snprintf(addr, sizeof(addr), fmt,
923 (unsigned long long)(res->start - offset),
924 (unsigned long long)(res->end - offset));
928 dev_info(&bus->dev, "root bus resource %pR%s\n", res, addr);
931 down_write(&pci_bus_sem);
932 list_add_tail(&bus->node, &pci_root_buses);
933 up_write(&pci_bus_sem);
938 put_device(&bridge->dev);
939 device_unregister(&bridge->dev);
946 static bool pci_bridge_child_ext_cfg_accessible(struct pci_dev *bridge)
952 * If extended config space isn't accessible on a bridge's primary
953 * bus, we certainly can't access it on the secondary bus.
955 if (bridge->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG)
959 * PCIe Root Ports and switch ports are PCIe on both sides, so if
960 * extended config space is accessible on the primary, it's also
961 * accessible on the secondary.
963 if (pci_is_pcie(bridge) &&
964 (pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT ||
965 pci_pcie_type(bridge) == PCI_EXP_TYPE_UPSTREAM ||
966 pci_pcie_type(bridge) == PCI_EXP_TYPE_DOWNSTREAM))
970 * For the other bridge types:
971 * - PCI-to-PCI bridges
972 * - PCIe-to-PCI/PCI-X forward bridges
973 * - PCI/PCI-X-to-PCIe reverse bridges
974 * extended config space on the secondary side is only accessible
975 * if the bridge supports PCI-X Mode 2.
977 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
981 pci_read_config_dword(bridge, pos + PCI_X_STATUS, &status);
982 return status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ);
985 static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
986 struct pci_dev *bridge, int busnr)
988 struct pci_bus *child;
992 /* Allocate a new bus and inherit stuff from the parent */
993 child = pci_alloc_bus(parent);
997 child->parent = parent;
998 child->ops = parent->ops;
999 child->msi = parent->msi;
1000 child->sysdata = parent->sysdata;
1001 child->bus_flags = parent->bus_flags;
1004 * Initialize some portions of the bus device, but don't register
1005 * it now as the parent is not properly set up yet.
1007 child->dev.class = &pcibus_class;
1008 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
1010 /* Set up the primary, secondary and subordinate bus numbers */
1011 child->number = child->busn_res.start = busnr;
1012 child->primary = parent->busn_res.start;
1013 child->busn_res.end = 0xff;
1016 child->dev.parent = parent->bridge;
1020 child->self = bridge;
1021 child->bridge = get_device(&bridge->dev);
1022 child->dev.parent = child->bridge;
1023 pci_set_bus_of_node(child);
1024 pci_set_bus_speed(child);
1027 * Check whether extended config space is accessible on the child
1028 * bus. Note that we currently assume it is always accessible on
1031 if (!pci_bridge_child_ext_cfg_accessible(bridge)) {
1032 child->bus_flags |= PCI_BUS_FLAGS_NO_EXTCFG;
1033 pci_info(child, "extended config space not accessible\n");
1036 /* Set up default resource pointers and names */
1037 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
1038 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
1039 child->resource[i]->name = child->name;
1041 bridge->subordinate = child;
1044 pci_set_bus_msi_domain(child);
1045 ret = device_register(&child->dev);
1048 pcibios_add_bus(child);
1050 if (child->ops->add_bus) {
1051 ret = child->ops->add_bus(child);
1052 if (WARN_ON(ret < 0))
1053 dev_err(&child->dev, "failed to add bus: %d\n", ret);
1056 /* Create legacy_io and legacy_mem files for this bus */
1057 pci_create_legacy_files(child);
1062 struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev,
1065 struct pci_bus *child;
1067 child = pci_alloc_child_bus(parent, dev, busnr);
1069 down_write(&pci_bus_sem);
1070 list_add_tail(&child->node, &parent->children);
1071 up_write(&pci_bus_sem);
1075 EXPORT_SYMBOL(pci_add_new_bus);
1077 static void pci_enable_crs(struct pci_dev *pdev)
1081 /* Enable CRS Software Visibility if supported */
1082 pcie_capability_read_word(pdev, PCI_EXP_RTCAP, &root_cap);
1083 if (root_cap & PCI_EXP_RTCAP_CRSVIS)
1084 pcie_capability_set_word(pdev, PCI_EXP_RTCTL,
1085 PCI_EXP_RTCTL_CRSSVE);
1088 static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
1089 unsigned int available_buses);
1091 * pci_ea_fixed_busnrs() - Read fixed Secondary and Subordinate bus
1092 * numbers from EA capability.
1094 * @sec: updated with secondary bus number from EA
1095 * @sub: updated with subordinate bus number from EA
1097 * If @dev is a bridge with EA capability, update @sec and @sub with
1098 * fixed bus numbers from the capability and return true. Otherwise,
1101 static bool pci_ea_fixed_busnrs(struct pci_dev *dev, u8 *sec, u8 *sub)
1106 if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE)
1109 /* find PCI EA capability in list */
1110 ea = pci_find_capability(dev, PCI_CAP_ID_EA);
1114 offset = ea + PCI_EA_FIRST_ENT;
1115 pci_read_config_dword(dev, offset, &dw);
1116 *sec = dw & PCI_EA_SEC_BUS_MASK;
1117 *sub = (dw & PCI_EA_SUB_BUS_MASK) >> PCI_EA_SUB_BUS_SHIFT;
1122 * pci_scan_bridge_extend() - Scan buses behind a bridge
1123 * @bus: Parent bus the bridge is on
1124 * @dev: Bridge itself
1125 * @max: Starting subordinate number of buses behind this bridge
1126 * @available_buses: Total number of buses available for this bridge and
1127 * the devices below. After the minimal bus space has
1128 * been allocated the remaining buses will be
1129 * distributed equally between hotplug-capable bridges.
1130 * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges
1131 * that need to be reconfigured.
1133 * If it's a bridge, configure it and scan the bus behind it.
1134 * For CardBus bridges, we don't scan behind as the devices will
1135 * be handled by the bridge driver itself.
1137 * We need to process bridges in two passes -- first we scan those
1138 * already configured by the BIOS and after we are done with all of
1139 * them, we proceed to assigning numbers to the remaining buses in
1140 * order to avoid overlaps between old and new bus numbers.
1142 * Return: New subordinate number covering all buses behind this bridge.
1144 static int pci_scan_bridge_extend(struct pci_bus *bus, struct pci_dev *dev,
1145 int max, unsigned int available_buses,
1148 struct pci_bus *child;
1149 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
1150 u32 buses, i, j = 0;
1152 u8 primary, secondary, subordinate;
1155 u8 fixed_sec, fixed_sub;
1159 * Make sure the bridge is powered on to be able to access config
1160 * space of devices below it.
1162 pm_runtime_get_sync(&dev->dev);
1164 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
1165 primary = buses & 0xFF;
1166 secondary = (buses >> 8) & 0xFF;
1167 subordinate = (buses >> 16) & 0xFF;
1169 pci_dbg(dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
1170 secondary, subordinate, pass);
1172 if (!primary && (primary != bus->number) && secondary && subordinate) {
1173 pci_warn(dev, "Primary bus is hard wired to 0\n");
1174 primary = bus->number;
1177 /* Check if setup is sensible at all */
1179 (primary != bus->number || secondary <= bus->number ||
1180 secondary > subordinate)) {
1181 pci_info(dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
1182 secondary, subordinate);
1187 * Disable Master-Abort Mode during probing to avoid reporting of
1188 * bus errors in some architectures.
1190 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
1191 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
1192 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
1194 pci_enable_crs(dev);
1196 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
1197 !is_cardbus && !broken) {
1201 * Bus already configured by firmware, process it in the
1202 * first pass and just note the configuration.
1208 * The bus might already exist for two reasons: Either we
1209 * are rescanning the bus or the bus is reachable through
1210 * more than one bridge. The second case can happen with
1211 * the i450NX chipset.
1213 child = pci_find_bus(pci_domain_nr(bus), secondary);
1215 child = pci_add_new_bus(bus, dev, secondary);
1218 child->primary = primary;
1219 pci_bus_insert_busn_res(child, secondary, subordinate);
1220 child->bridge_ctl = bctl;
1223 cmax = pci_scan_child_bus(child);
1224 if (cmax > subordinate)
1225 pci_warn(dev, "bridge has subordinate %02x but max busn %02x\n",
1228 /* Subordinate should equal child->busn_res.end */
1229 if (subordinate > max)
1234 * We need to assign a number to this bus which we always
1235 * do in the second pass.
1238 if (pcibios_assign_all_busses() || broken || is_cardbus)
1241 * Temporarily disable forwarding of the
1242 * configuration cycles on all bridges in
1243 * this bus segment to avoid possible
1244 * conflicts in the second pass between two
1245 * bridges programmed with overlapping bus
1248 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
1254 pci_write_config_word(dev, PCI_STATUS, 0xffff);
1256 /* Read bus numbers from EA Capability (if present) */
1257 fixed_buses = pci_ea_fixed_busnrs(dev, &fixed_sec, &fixed_sub);
1259 next_busnr = fixed_sec;
1261 next_busnr = max + 1;
1264 * Prevent assigning a bus number that already exists.
1265 * This can happen when a bridge is hot-plugged, so in this
1266 * case we only re-scan this bus.
1268 child = pci_find_bus(pci_domain_nr(bus), next_busnr);
1270 child = pci_add_new_bus(bus, dev, next_busnr);
1273 pci_bus_insert_busn_res(child, next_busnr,
1277 if (available_buses)
1280 buses = (buses & 0xff000000)
1281 | ((unsigned int)(child->primary) << 0)
1282 | ((unsigned int)(child->busn_res.start) << 8)
1283 | ((unsigned int)(child->busn_res.end) << 16);
1286 * yenta.c forces a secondary latency timer of 176.
1287 * Copy that behaviour here.
1290 buses &= ~0xff000000;
1291 buses |= CARDBUS_LATENCY_TIMER << 24;
1294 /* We need to blast all three values with a single write */
1295 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
1298 child->bridge_ctl = bctl;
1299 max = pci_scan_child_bus_extend(child, available_buses);
1303 * For CardBus bridges, we leave 4 bus numbers as
1304 * cards with a PCI-to-PCI bridge can be inserted
1307 for (i = 0; i < CARDBUS_RESERVE_BUSNR; i++) {
1308 struct pci_bus *parent = bus;
1309 if (pci_find_bus(pci_domain_nr(bus),
1312 while (parent->parent) {
1313 if ((!pcibios_assign_all_busses()) &&
1314 (parent->busn_res.end > max) &&
1315 (parent->busn_res.end <= max+i)) {
1318 parent = parent->parent;
1323 * Often, there are two CardBus
1324 * bridges -- try to leave one
1325 * valid bus number for each one.
1335 * Set subordinate bus number to its real value.
1336 * If fixed subordinate bus number exists from EA
1337 * capability then use it.
1341 pci_bus_update_busn_res_end(child, max);
1342 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
1345 sprintf(child->name,
1346 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
1347 pci_domain_nr(bus), child->number);
1349 /* Check that all devices are accessible */
1350 while (bus->parent) {
1351 if ((child->busn_res.end > bus->busn_res.end) ||
1352 (child->number > bus->busn_res.end) ||
1353 (child->number < bus->number) ||
1354 (child->busn_res.end < bus->number)) {
1355 dev_info(&dev->dev, "devices behind bridge are unusable because %pR cannot be assigned for them\n",
1363 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
1365 pm_runtime_put(&dev->dev);
1371 * pci_scan_bridge() - Scan buses behind a bridge
1372 * @bus: Parent bus the bridge is on
1373 * @dev: Bridge itself
1374 * @max: Starting subordinate number of buses behind this bridge
1375 * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges
1376 * that need to be reconfigured.
1378 * If it's a bridge, configure it and scan the bus behind it.
1379 * For CardBus bridges, we don't scan behind as the devices will
1380 * be handled by the bridge driver itself.
1382 * We need to process bridges in two passes -- first we scan those
1383 * already configured by the BIOS and after we are done with all of
1384 * them, we proceed to assigning numbers to the remaining buses in
1385 * order to avoid overlaps between old and new bus numbers.
1387 * Return: New subordinate number covering all buses behind this bridge.
1389 int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
1391 return pci_scan_bridge_extend(bus, dev, max, 0, pass);
1393 EXPORT_SYMBOL(pci_scan_bridge);
1396 * Read interrupt line and base address registers.
1397 * The architecture-dependent code can tweak these, of course.
1399 static void pci_read_irq(struct pci_dev *dev)
1403 /* VFs are not allowed to use INTx, so skip the config reads */
1404 if (dev->is_virtfn) {
1410 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
1413 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
1417 void set_pcie_port_type(struct pci_dev *pdev)
1422 struct pci_dev *parent;
1424 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
1428 pdev->pcie_cap = pos;
1429 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
1430 pdev->pcie_flags_reg = reg16;
1431 pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16);
1432 pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
1435 * A Root Port or a PCI-to-PCIe bridge is always the upstream end
1436 * of a Link. No PCIe component has two Links. Two Links are
1437 * connected by a Switch that has a Port on each Link and internal
1438 * logic to connect the two Ports.
1440 type = pci_pcie_type(pdev);
1441 if (type == PCI_EXP_TYPE_ROOT_PORT ||
1442 type == PCI_EXP_TYPE_PCIE_BRIDGE)
1443 pdev->has_secondary_link = 1;
1444 else if (type == PCI_EXP_TYPE_UPSTREAM ||
1445 type == PCI_EXP_TYPE_DOWNSTREAM) {
1446 parent = pci_upstream_bridge(pdev);
1449 * Usually there's an upstream device (Root Port or Switch
1450 * Downstream Port), but we can't assume one exists.
1452 if (parent && !parent->has_secondary_link)
1453 pdev->has_secondary_link = 1;
1457 void set_pcie_hotplug_bridge(struct pci_dev *pdev)
1461 pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32);
1462 if (reg32 & PCI_EXP_SLTCAP_HPC)
1463 pdev->is_hotplug_bridge = 1;
1466 static void set_pcie_thunderbolt(struct pci_dev *dev)
1471 while ((vsec = pci_find_next_ext_capability(dev, vsec,
1472 PCI_EXT_CAP_ID_VNDR))) {
1473 pci_read_config_dword(dev, vsec + PCI_VNDR_HEADER, &header);
1475 /* Is the device part of a Thunderbolt controller? */
1476 if (dev->vendor == PCI_VENDOR_ID_INTEL &&
1477 PCI_VNDR_HEADER_ID(header) == PCI_VSEC_ID_INTEL_TBT) {
1478 dev->is_thunderbolt = 1;
1484 static void set_pcie_untrusted(struct pci_dev *dev)
1486 struct pci_dev *parent;
1489 * If the upstream bridge is untrusted we treat this device
1490 * untrusted as well.
1492 parent = pci_upstream_bridge(dev);
1493 if (parent && parent->untrusted)
1494 dev->untrusted = true;
1498 * pci_ext_cfg_is_aliased - Is ext config space just an alias of std config?
1501 * PCI Express to PCI/PCI-X Bridge Specification, rev 1.0, 4.1.4 says that
1502 * when forwarding a type1 configuration request the bridge must check that
1503 * the extended register address field is zero. The bridge is not permitted
1504 * to forward the transactions and must handle it as an Unsupported Request.
1505 * Some bridges do not follow this rule and simply drop the extended register
1506 * bits, resulting in the standard config space being aliased, every 256
1507 * bytes across the entire configuration space. Test for this condition by
1508 * comparing the first dword of each potential alias to the vendor/device ID.
1510 * ASM1083/1085 PCIe-to-PCI Reversible Bridge (1b21:1080, rev 01 & 03)
1511 * AMD/ATI SBx00 PCI to PCI Bridge (1002:4384, rev 40)
1513 static bool pci_ext_cfg_is_aliased(struct pci_dev *dev)
1515 #ifdef CONFIG_PCI_QUIRKS
1519 pci_read_config_dword(dev, PCI_VENDOR_ID, &header);
1521 for (pos = PCI_CFG_SPACE_SIZE;
1522 pos < PCI_CFG_SPACE_EXP_SIZE; pos += PCI_CFG_SPACE_SIZE) {
1523 if (pci_read_config_dword(dev, pos, &tmp) != PCIBIOS_SUCCESSFUL
1535 * pci_cfg_space_size - Get the configuration space size of the PCI device
1538 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1539 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1540 * access it. Maybe we don't have a way to generate extended config space
1541 * accesses, or the device is behind a reverse Express bridge. So we try
1542 * reading the dword at 0x100 which must either be 0 or a valid extended
1543 * capability header.
1545 static int pci_cfg_space_size_ext(struct pci_dev *dev)
1548 int pos = PCI_CFG_SPACE_SIZE;
1550 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1551 return PCI_CFG_SPACE_SIZE;
1552 if (status == 0xffffffff || pci_ext_cfg_is_aliased(dev))
1553 return PCI_CFG_SPACE_SIZE;
1555 return PCI_CFG_SPACE_EXP_SIZE;
1558 #ifdef CONFIG_PCI_IOV
1559 static bool is_vf0(struct pci_dev *dev)
1561 if (pci_iov_virtfn_devfn(dev->physfn, 0) == dev->devfn &&
1562 pci_iov_virtfn_bus(dev->physfn, 0) == dev->bus->number)
1569 int pci_cfg_space_size(struct pci_dev *dev)
1575 #ifdef CONFIG_PCI_IOV
1576 /* Read cached value for all VFs except for VF0 */
1577 if (dev->is_virtfn && !is_vf0(dev))
1578 return dev->physfn->sriov->cfg_size;
1581 if (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG)
1582 return PCI_CFG_SPACE_SIZE;
1584 class = dev->class >> 8;
1585 if (class == PCI_CLASS_BRIDGE_HOST)
1586 return pci_cfg_space_size_ext(dev);
1588 if (pci_is_pcie(dev))
1589 return pci_cfg_space_size_ext(dev);
1591 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1593 return PCI_CFG_SPACE_SIZE;
1595 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1596 if (status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ))
1597 return pci_cfg_space_size_ext(dev);
1599 return PCI_CFG_SPACE_SIZE;
1602 static u32 pci_class(struct pci_dev *dev)
1606 #ifdef CONFIG_PCI_IOV
1608 return dev->physfn->sriov->class;
1610 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
1614 static void pci_subsystem_ids(struct pci_dev *dev, u16 *vendor, u16 *device)
1616 #ifdef CONFIG_PCI_IOV
1617 if (dev->is_virtfn) {
1618 *vendor = dev->physfn->sriov->subsystem_vendor;
1619 *device = dev->physfn->sriov->subsystem_device;
1623 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, vendor);
1624 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, device);
1627 static u8 pci_hdr_type(struct pci_dev *dev)
1631 #ifdef CONFIG_PCI_IOV
1633 return dev->physfn->sriov->hdr_type;
1635 pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type);
1639 #define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
1641 static void pci_msi_setup_pci_dev(struct pci_dev *dev)
1644 * Disable the MSI hardware to avoid screaming interrupts
1645 * during boot. This is the power on reset default so
1646 * usually this should be a noop.
1648 dev->msi_cap = pci_find_capability(dev, PCI_CAP_ID_MSI);
1650 pci_msi_set_enable(dev, 0);
1652 dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX);
1654 pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
1658 * pci_intx_mask_broken - Test PCI_COMMAND_INTX_DISABLE writability
1661 * Test whether PCI_COMMAND_INTX_DISABLE is writable for @dev. Check this
1662 * at enumeration-time to avoid modifying PCI_COMMAND at run-time.
1664 static int pci_intx_mask_broken(struct pci_dev *dev)
1666 u16 orig, toggle, new;
1668 pci_read_config_word(dev, PCI_COMMAND, &orig);
1669 toggle = orig ^ PCI_COMMAND_INTX_DISABLE;
1670 pci_write_config_word(dev, PCI_COMMAND, toggle);
1671 pci_read_config_word(dev, PCI_COMMAND, &new);
1673 pci_write_config_word(dev, PCI_COMMAND, orig);
1676 * PCI_COMMAND_INTX_DISABLE was reserved and read-only prior to PCI
1677 * r2.3, so strictly speaking, a device is not *broken* if it's not
1678 * writable. But we'll live with the misnomer for now.
1685 static void early_dump_pci_device(struct pci_dev *pdev)
1690 pci_info(pdev, "config space:\n");
1692 for (i = 0; i < 256; i += 4)
1693 pci_read_config_dword(pdev, i, &value[i / 4]);
1695 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 1,
1700 * pci_setup_device - Fill in class and map information of a device
1701 * @dev: the device structure to fill
1703 * Initialize the device structure with information about the device's
1704 * vendor,class,memory and IO-space addresses, IRQ lines etc.
1705 * Called at initialisation of the PCI subsystem and by CardBus services.
1706 * Returns 0 on success and negative if unknown type of device (not normal,
1707 * bridge or CardBus).
1709 int pci_setup_device(struct pci_dev *dev)
1715 struct pci_bus_region region;
1716 struct resource *res;
1718 hdr_type = pci_hdr_type(dev);
1720 dev->sysdata = dev->bus->sysdata;
1721 dev->dev.parent = dev->bus->bridge;
1722 dev->dev.bus = &pci_bus_type;
1723 dev->hdr_type = hdr_type & 0x7f;
1724 dev->multifunction = !!(hdr_type & 0x80);
1725 dev->error_state = pci_channel_io_normal;
1726 set_pcie_port_type(dev);
1728 pci_dev_assign_slot(dev);
1731 * Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
1732 * set this higher, assuming the system even supports it.
1734 dev->dma_mask = 0xffffffff;
1736 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
1737 dev->bus->number, PCI_SLOT(dev->devfn),
1738 PCI_FUNC(dev->devfn));
1740 class = pci_class(dev);
1742 dev->revision = class & 0xff;
1743 dev->class = class >> 8; /* upper 3 bytes */
1745 pci_info(dev, "[%04x:%04x] type %02x class %#08x\n",
1746 dev->vendor, dev->device, dev->hdr_type, dev->class);
1749 early_dump_pci_device(dev);
1751 /* Need to have dev->class ready */
1752 dev->cfg_size = pci_cfg_space_size(dev);
1754 /* Need to have dev->cfg_size ready */
1755 set_pcie_thunderbolt(dev);
1757 set_pcie_untrusted(dev);
1759 /* "Unknown power state" */
1760 dev->current_state = PCI_UNKNOWN;
1762 /* Early fixups, before probing the BARs */
1763 pci_fixup_device(pci_fixup_early, dev);
1765 /* Device class may be changed after fixup */
1766 class = dev->class >> 8;
1768 if (dev->non_compliant_bars) {
1769 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1770 if (cmd & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) {
1771 pci_info(dev, "device has non-compliant BARs; disabling IO/MEM decoding\n");
1772 cmd &= ~PCI_COMMAND_IO;
1773 cmd &= ~PCI_COMMAND_MEMORY;
1774 pci_write_config_word(dev, PCI_COMMAND, cmd);
1778 dev->broken_intx_masking = pci_intx_mask_broken(dev);
1780 switch (dev->hdr_type) { /* header type */
1781 case PCI_HEADER_TYPE_NORMAL: /* standard header */
1782 if (class == PCI_CLASS_BRIDGE_PCI)
1785 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1787 pci_subsystem_ids(dev, &dev->subsystem_vendor, &dev->subsystem_device);
1790 * Do the ugly legacy mode stuff here rather than broken chip
1791 * quirk code. Legacy mode ATA controllers have fixed
1792 * addresses. These are not always echoed in BAR0-3, and
1793 * BAR0-3 in a few cases contain junk!
1795 if (class == PCI_CLASS_STORAGE_IDE) {
1797 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1798 if ((progif & 1) == 0) {
1799 region.start = 0x1F0;
1801 res = &dev->resource[0];
1802 res->flags = LEGACY_IO_RESOURCE;
1803 pcibios_bus_to_resource(dev->bus, res, ®ion);
1804 pci_info(dev, "legacy IDE quirk: reg 0x10: %pR\n",
1806 region.start = 0x3F6;
1808 res = &dev->resource[1];
1809 res->flags = LEGACY_IO_RESOURCE;
1810 pcibios_bus_to_resource(dev->bus, res, ®ion);
1811 pci_info(dev, "legacy IDE quirk: reg 0x14: %pR\n",
1814 if ((progif & 4) == 0) {
1815 region.start = 0x170;
1817 res = &dev->resource[2];
1818 res->flags = LEGACY_IO_RESOURCE;
1819 pcibios_bus_to_resource(dev->bus, res, ®ion);
1820 pci_info(dev, "legacy IDE quirk: reg 0x18: %pR\n",
1822 region.start = 0x376;
1824 res = &dev->resource[3];
1825 res->flags = LEGACY_IO_RESOURCE;
1826 pcibios_bus_to_resource(dev->bus, res, ®ion);
1827 pci_info(dev, "legacy IDE quirk: reg 0x1c: %pR\n",
1833 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1835 * The PCI-to-PCI bridge spec requires that subtractive
1836 * decoding (i.e. transparent) bridge must have programming
1837 * interface code of 0x01.
1840 dev->transparent = ((dev->class & 0xff) == 1);
1841 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1842 pci_read_bridge_windows(dev);
1843 set_pcie_hotplug_bridge(dev);
1844 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1846 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1847 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1851 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1852 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1855 pci_read_bases(dev, 1, 0);
1856 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1857 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1860 default: /* unknown header */
1861 pci_err(dev, "unknown header type %02x, ignoring device\n",
1866 pci_err(dev, "ignoring class %#08x (doesn't match header type %02x)\n",
1867 dev->class, dev->hdr_type);
1868 dev->class = PCI_CLASS_NOT_DEFINED << 8;
1871 /* We found a fine healthy device, go go go... */
1875 static void pci_configure_mps(struct pci_dev *dev)
1877 struct pci_dev *bridge = pci_upstream_bridge(dev);
1878 int mps, mpss, p_mps, rc;
1880 if (!pci_is_pcie(dev) || !bridge || !pci_is_pcie(bridge))
1883 /* MPS and MRRS fields are of type 'RsvdP' for VFs, short-circuit out */
1887 mps = pcie_get_mps(dev);
1888 p_mps = pcie_get_mps(bridge);
1893 if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
1894 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",
1895 mps, pci_name(bridge), p_mps);
1900 * Fancier MPS configuration is done later by
1901 * pcie_bus_configure_settings()
1903 if (pcie_bus_config != PCIE_BUS_DEFAULT)
1906 mpss = 128 << dev->pcie_mpss;
1907 if (mpss < p_mps && pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT) {
1908 pcie_set_mps(bridge, mpss);
1909 pci_info(dev, "Upstream bridge's Max Payload Size set to %d (was %d, max %d)\n",
1910 mpss, p_mps, 128 << bridge->pcie_mpss);
1911 p_mps = pcie_get_mps(bridge);
1914 rc = pcie_set_mps(dev, p_mps);
1916 pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
1921 pci_info(dev, "Max Payload Size set to %d (was %d, max %d)\n",
1925 static struct hpp_type0 pci_default_type0 = {
1927 .cache_line_size = 8,
1928 .latency_timer = 0x40,
1933 static void program_hpp_type0(struct pci_dev *dev, struct hpp_type0 *hpp)
1935 u16 pci_cmd, pci_bctl;
1938 hpp = &pci_default_type0;
1940 if (hpp->revision > 1) {
1941 pci_warn(dev, "PCI settings rev %d not supported; using defaults\n",
1943 hpp = &pci_default_type0;
1946 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, hpp->cache_line_size);
1947 pci_write_config_byte(dev, PCI_LATENCY_TIMER, hpp->latency_timer);
1948 pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
1949 if (hpp->enable_serr)
1950 pci_cmd |= PCI_COMMAND_SERR;
1951 if (hpp->enable_perr)
1952 pci_cmd |= PCI_COMMAND_PARITY;
1953 pci_write_config_word(dev, PCI_COMMAND, pci_cmd);
1955 /* Program bridge control value */
1956 if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
1957 pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER,
1958 hpp->latency_timer);
1959 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &pci_bctl);
1960 if (hpp->enable_perr)
1961 pci_bctl |= PCI_BRIDGE_CTL_PARITY;
1962 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, pci_bctl);
1966 static void program_hpp_type1(struct pci_dev *dev, struct hpp_type1 *hpp)
1973 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1977 pci_warn(dev, "PCI-X settings not supported\n");
1980 static bool pcie_root_rcb_set(struct pci_dev *dev)
1982 struct pci_dev *rp = pcie_find_root_port(dev);
1988 pcie_capability_read_word(rp, PCI_EXP_LNKCTL, &lnkctl);
1989 if (lnkctl & PCI_EXP_LNKCTL_RCB)
1995 static void program_hpp_type2(struct pci_dev *dev, struct hpp_type2 *hpp)
2003 if (!pci_is_pcie(dev))
2006 if (hpp->revision > 1) {
2007 pci_warn(dev, "PCIe settings rev %d not supported\n",
2013 * Don't allow _HPX to change MPS or MRRS settings. We manage
2014 * those to make sure they're consistent with the rest of the
2017 hpp->pci_exp_devctl_and |= PCI_EXP_DEVCTL_PAYLOAD |
2018 PCI_EXP_DEVCTL_READRQ;
2019 hpp->pci_exp_devctl_or &= ~(PCI_EXP_DEVCTL_PAYLOAD |
2020 PCI_EXP_DEVCTL_READRQ);
2022 /* Initialize Device Control Register */
2023 pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
2024 ~hpp->pci_exp_devctl_and, hpp->pci_exp_devctl_or);
2026 /* Initialize Link Control Register */
2027 if (pcie_cap_has_lnkctl(dev)) {
2030 * If the Root Port supports Read Completion Boundary of
2031 * 128, set RCB to 128. Otherwise, clear it.
2033 hpp->pci_exp_lnkctl_and |= PCI_EXP_LNKCTL_RCB;
2034 hpp->pci_exp_lnkctl_or &= ~PCI_EXP_LNKCTL_RCB;
2035 if (pcie_root_rcb_set(dev))
2036 hpp->pci_exp_lnkctl_or |= PCI_EXP_LNKCTL_RCB;
2038 pcie_capability_clear_and_set_word(dev, PCI_EXP_LNKCTL,
2039 ~hpp->pci_exp_lnkctl_and, hpp->pci_exp_lnkctl_or);
2042 /* Find Advanced Error Reporting Enhanced Capability */
2043 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
2047 /* Initialize Uncorrectable Error Mask Register */
2048 pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, ®32);
2049 reg32 = (reg32 & hpp->unc_err_mask_and) | hpp->unc_err_mask_or;
2050 pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, reg32);
2052 /* Initialize Uncorrectable Error Severity Register */
2053 pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, ®32);
2054 reg32 = (reg32 & hpp->unc_err_sever_and) | hpp->unc_err_sever_or;
2055 pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, reg32);
2057 /* Initialize Correctable Error Mask Register */
2058 pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK, ®32);
2059 reg32 = (reg32 & hpp->cor_err_mask_and) | hpp->cor_err_mask_or;
2060 pci_write_config_dword(dev, pos + PCI_ERR_COR_MASK, reg32);
2062 /* Initialize Advanced Error Capabilities and Control Register */
2063 pci_read_config_dword(dev, pos + PCI_ERR_CAP, ®32);
2064 reg32 = (reg32 & hpp->adv_err_cap_and) | hpp->adv_err_cap_or;
2066 /* Don't enable ECRC generation or checking if unsupported */
2067 if (!(reg32 & PCI_ERR_CAP_ECRC_GENC))
2068 reg32 &= ~PCI_ERR_CAP_ECRC_GENE;
2069 if (!(reg32 & PCI_ERR_CAP_ECRC_CHKC))
2070 reg32 &= ~PCI_ERR_CAP_ECRC_CHKE;
2071 pci_write_config_dword(dev, pos + PCI_ERR_CAP, reg32);
2074 * FIXME: The following two registers are not supported yet.
2076 * o Secondary Uncorrectable Error Severity Register
2077 * o Secondary Uncorrectable Error Mask Register
2081 static u16 hpx3_device_type(struct pci_dev *dev)
2083 u16 pcie_type = pci_pcie_type(dev);
2084 const int pcie_to_hpx3_type[] = {
2085 [PCI_EXP_TYPE_ENDPOINT] = HPX_TYPE_ENDPOINT,
2086 [PCI_EXP_TYPE_LEG_END] = HPX_TYPE_LEG_END,
2087 [PCI_EXP_TYPE_RC_END] = HPX_TYPE_RC_END,
2088 [PCI_EXP_TYPE_RC_EC] = HPX_TYPE_RC_EC,
2089 [PCI_EXP_TYPE_ROOT_PORT] = HPX_TYPE_ROOT_PORT,
2090 [PCI_EXP_TYPE_UPSTREAM] = HPX_TYPE_UPSTREAM,
2091 [PCI_EXP_TYPE_DOWNSTREAM] = HPX_TYPE_DOWNSTREAM,
2092 [PCI_EXP_TYPE_PCI_BRIDGE] = HPX_TYPE_PCI_BRIDGE,
2093 [PCI_EXP_TYPE_PCIE_BRIDGE] = HPX_TYPE_PCIE_BRIDGE,
2096 if (pcie_type >= ARRAY_SIZE(pcie_to_hpx3_type))
2099 return pcie_to_hpx3_type[pcie_type];
2102 static u8 hpx3_function_type(struct pci_dev *dev)
2105 return HPX_FN_SRIOV_VIRT;
2106 else if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV) > 0)
2107 return HPX_FN_SRIOV_PHYS;
2109 return HPX_FN_NORMAL;
2112 static bool hpx3_cap_ver_matches(u8 pcie_cap_id, u8 hpx3_cap_id)
2114 u8 cap_ver = hpx3_cap_id & 0xf;
2116 if ((hpx3_cap_id & BIT(4)) && cap_ver >= pcie_cap_id)
2118 else if (cap_ver == pcie_cap_id)
2124 static void program_hpx_type3_register(struct pci_dev *dev,
2125 const struct hpx_type3 *reg)
2127 u32 match_reg, write_reg, header, orig_value;
2130 if (!(hpx3_device_type(dev) & reg->device_type))
2133 if (!(hpx3_function_type(dev) & reg->function_type))
2136 switch (reg->config_space_location) {
2137 case HPX_CFG_PCICFG:
2140 case HPX_CFG_PCIE_CAP:
2141 pos = pci_find_capability(dev, reg->pci_exp_cap_id);
2146 case HPX_CFG_PCIE_CAP_EXT:
2147 pos = pci_find_ext_capability(dev, reg->pci_exp_cap_id);
2151 pci_read_config_dword(dev, pos, &header);
2152 if (!hpx3_cap_ver_matches(PCI_EXT_CAP_VER(header),
2153 reg->pci_exp_cap_ver))
2157 case HPX_CFG_VEND_CAP: /* Fall through */
2158 case HPX_CFG_DVSEC: /* Fall through */
2160 pci_warn(dev, "Encountered _HPX type 3 with unsupported config space location");
2164 pci_read_config_dword(dev, pos + reg->match_offset, &match_reg);
2166 if ((match_reg & reg->match_mask_and) != reg->match_value)
2169 pci_read_config_dword(dev, pos + reg->reg_offset, &write_reg);
2170 orig_value = write_reg;
2171 write_reg &= reg->reg_mask_and;
2172 write_reg |= reg->reg_mask_or;
2174 if (orig_value == write_reg)
2177 pci_write_config_dword(dev, pos + reg->reg_offset, write_reg);
2179 pci_dbg(dev, "Applied _HPX3 at [0x%x]: 0x%08x -> 0x%08x",
2180 pos, orig_value, write_reg);
2183 static void program_hpx_type3(struct pci_dev *dev, struct hpx_type3 *hpx3)
2188 if (!pci_is_pcie(dev))
2191 program_hpx_type3_register(dev, hpx3);
2194 int pci_configure_extended_tags(struct pci_dev *dev, void *ign)
2196 struct pci_host_bridge *host;
2201 if (!pci_is_pcie(dev))
2204 ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap);
2208 if (!(cap & PCI_EXP_DEVCAP_EXT_TAG))
2211 ret = pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
2215 host = pci_find_host_bridge(dev->bus);
2220 * If some device in the hierarchy doesn't handle Extended Tags
2221 * correctly, make sure they're disabled.
2223 if (host->no_ext_tags) {
2224 if (ctl & PCI_EXP_DEVCTL_EXT_TAG) {
2225 pci_info(dev, "disabling Extended Tags\n");
2226 pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
2227 PCI_EXP_DEVCTL_EXT_TAG);
2232 if (!(ctl & PCI_EXP_DEVCTL_EXT_TAG)) {
2233 pci_info(dev, "enabling Extended Tags\n");
2234 pcie_capability_set_word(dev, PCI_EXP_DEVCTL,
2235 PCI_EXP_DEVCTL_EXT_TAG);
2241 * pcie_relaxed_ordering_enabled - Probe for PCIe relaxed ordering enable
2242 * @dev: PCI device to query
2244 * Returns true if the device has enabled relaxed ordering attribute.
2246 bool pcie_relaxed_ordering_enabled(struct pci_dev *dev)
2250 pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &v);
2252 return !!(v & PCI_EXP_DEVCTL_RELAX_EN);
2254 EXPORT_SYMBOL(pcie_relaxed_ordering_enabled);
2256 static void pci_configure_relaxed_ordering(struct pci_dev *dev)
2258 struct pci_dev *root;
2260 /* PCI_EXP_DEVICE_RELAX_EN is RsvdP in VFs */
2264 if (!pcie_relaxed_ordering_enabled(dev))
2268 * For now, we only deal with Relaxed Ordering issues with Root
2269 * Ports. Peer-to-Peer DMA is another can of worms.
2271 root = pci_find_pcie_root_port(dev);
2275 if (root->dev_flags & PCI_DEV_FLAGS_NO_RELAXED_ORDERING) {
2276 pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
2277 PCI_EXP_DEVCTL_RELAX_EN);
2278 pci_info(dev, "Relaxed Ordering disabled because the Root Port didn't support it\n");
2282 static void pci_configure_ltr(struct pci_dev *dev)
2284 #ifdef CONFIG_PCIEASPM
2285 struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
2286 struct pci_dev *bridge;
2289 if (!pci_is_pcie(dev))
2292 pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
2293 if (!(cap & PCI_EXP_DEVCAP2_LTR))
2296 pcie_capability_read_dword(dev, PCI_EXP_DEVCTL2, &ctl);
2297 if (ctl & PCI_EXP_DEVCTL2_LTR_EN) {
2298 if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
2303 bridge = pci_upstream_bridge(dev);
2304 if (bridge && bridge->ltr_path)
2310 if (!host->native_ltr)
2314 * Software must not enable LTR in an Endpoint unless the Root
2315 * Complex and all intermediate Switches indicate support for LTR.
2316 * PCIe r4.0, sec 6.18.
2318 if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT ||
2319 ((bridge = pci_upstream_bridge(dev)) &&
2320 bridge->ltr_path)) {
2321 pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
2322 PCI_EXP_DEVCTL2_LTR_EN);
2328 static void pci_configure_eetlp_prefix(struct pci_dev *dev)
2330 #ifdef CONFIG_PCI_PASID
2331 struct pci_dev *bridge;
2335 if (!pci_is_pcie(dev))
2338 pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
2339 if (!(cap & PCI_EXP_DEVCAP2_EE_PREFIX))
2342 pcie_type = pci_pcie_type(dev);
2343 if (pcie_type == PCI_EXP_TYPE_ROOT_PORT ||
2344 pcie_type == PCI_EXP_TYPE_RC_END)
2345 dev->eetlp_prefix_path = 1;
2347 bridge = pci_upstream_bridge(dev);
2348 if (bridge && bridge->eetlp_prefix_path)
2349 dev->eetlp_prefix_path = 1;
2354 static void pci_configure_serr(struct pci_dev *dev)
2358 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
2361 * A bridge will not forward ERR_ messages coming from an
2362 * endpoint unless SERR# forwarding is enabled.
2364 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &control);
2365 if (!(control & PCI_BRIDGE_CTL_SERR)) {
2366 control |= PCI_BRIDGE_CTL_SERR;
2367 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, control);
2372 static void pci_configure_device(struct pci_dev *dev)
2374 static const struct hotplug_program_ops hp_ops = {
2375 .program_type0 = program_hpp_type0,
2376 .program_type1 = program_hpp_type1,
2377 .program_type2 = program_hpp_type2,
2378 .program_type3 = program_hpx_type3,
2381 pci_configure_mps(dev);
2382 pci_configure_extended_tags(dev, NULL);
2383 pci_configure_relaxed_ordering(dev);
2384 pci_configure_ltr(dev);
2385 pci_configure_eetlp_prefix(dev);
2386 pci_configure_serr(dev);
2388 pci_acpi_program_hp_params(dev, &hp_ops);
2391 static void pci_release_capabilities(struct pci_dev *dev)
2394 pci_vpd_release(dev);
2395 pci_iov_release(dev);
2396 pci_free_cap_save_buffers(dev);
2400 * pci_release_dev - Free a PCI device structure when all users of it are
2402 * @dev: device that's been disconnected
2404 * Will be called only by the device core when all users of this PCI device are
2407 static void pci_release_dev(struct device *dev)
2409 struct pci_dev *pci_dev;
2411 pci_dev = to_pci_dev(dev);
2412 pci_release_capabilities(pci_dev);
2413 pci_release_of_node(pci_dev);
2414 pcibios_release_device(pci_dev);
2415 pci_bus_put(pci_dev->bus);
2416 kfree(pci_dev->driver_override);
2417 bitmap_free(pci_dev->dma_alias_mask);
2421 struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
2423 struct pci_dev *dev;
2425 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
2429 INIT_LIST_HEAD(&dev->bus_list);
2430 dev->dev.type = &pci_dev_type;
2431 dev->bus = pci_bus_get(bus);
2435 EXPORT_SYMBOL(pci_alloc_dev);
2437 static bool pci_bus_crs_vendor_id(u32 l)
2439 return (l & 0xffff) == 0x0001;
2442 static bool pci_bus_wait_crs(struct pci_bus *bus, int devfn, u32 *l,
2447 if (!pci_bus_crs_vendor_id(*l))
2448 return true; /* not a CRS completion */
2451 return false; /* CRS, but caller doesn't want to wait */
2454 * We got the reserved Vendor ID that indicates a completion with
2455 * Configuration Request Retry Status (CRS). Retry until we get a
2456 * valid Vendor ID or we time out.
2458 while (pci_bus_crs_vendor_id(*l)) {
2459 if (delay > timeout) {
2460 pr_warn("pci %04x:%02x:%02x.%d: not ready after %dms; giving up\n",
2461 pci_domain_nr(bus), bus->number,
2462 PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2467 pr_info("pci %04x:%02x:%02x.%d: not ready after %dms; waiting\n",
2468 pci_domain_nr(bus), bus->number,
2469 PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2474 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
2479 pr_info("pci %04x:%02x:%02x.%d: ready after %dms\n",
2480 pci_domain_nr(bus), bus->number,
2481 PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2486 bool pci_bus_generic_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
2489 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
2492 /* Some broken boards return 0 or ~0 if a slot is empty: */
2493 if (*l == 0xffffffff || *l == 0x00000000 ||
2494 *l == 0x0000ffff || *l == 0xffff0000)
2497 if (pci_bus_crs_vendor_id(*l))
2498 return pci_bus_wait_crs(bus, devfn, l, timeout);
2503 bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
2506 #ifdef CONFIG_PCI_QUIRKS
2507 struct pci_dev *bridge = bus->self;
2510 * Certain IDT switches have an issue where they improperly trigger
2511 * ACS Source Validation errors on completions for config reads.
2513 if (bridge && bridge->vendor == PCI_VENDOR_ID_IDT &&
2514 bridge->device == 0x80b5)
2515 return pci_idt_bus_quirk(bus, devfn, l, timeout);
2518 return pci_bus_generic_read_dev_vendor_id(bus, devfn, l, timeout);
2520 EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
2523 * Read the config data for a PCI device, sanity-check it,
2524 * and fill in the dev structure.
2526 static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
2528 struct pci_dev *dev;
2531 if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
2534 dev = pci_alloc_dev(bus);
2539 dev->vendor = l & 0xffff;
2540 dev->device = (l >> 16) & 0xffff;
2542 pci_set_of_node(dev);
2544 if (pci_setup_device(dev)) {
2545 pci_bus_put(dev->bus);
2553 void pcie_report_downtraining(struct pci_dev *dev)
2555 if (!pci_is_pcie(dev))
2558 /* Look from the device up to avoid downstream ports with no devices */
2559 if ((pci_pcie_type(dev) != PCI_EXP_TYPE_ENDPOINT) &&
2560 (pci_pcie_type(dev) != PCI_EXP_TYPE_LEG_END) &&
2561 (pci_pcie_type(dev) != PCI_EXP_TYPE_UPSTREAM))
2564 /* Multi-function PCIe devices share the same link/status */
2565 if (PCI_FUNC(dev->devfn) != 0 || dev->is_virtfn)
2568 /* Print link status only if the device is constrained by the fabric */
2569 __pcie_print_link_status(dev, false);
2572 static void pci_init_capabilities(struct pci_dev *dev)
2574 /* Enhanced Allocation */
2577 /* Setup MSI caps & disable MSI/MSI-X interrupts */
2578 pci_msi_setup_pci_dev(dev);
2580 /* Buffers for saving PCIe and PCI-X capabilities */
2581 pci_allocate_cap_save_buffers(dev);
2583 /* Power Management */
2586 /* Vital Product Data */
2589 /* Alternative Routing-ID Forwarding */
2590 pci_configure_ari(dev);
2592 /* Single Root I/O Virtualization */
2595 /* Address Translation Services */
2598 /* Enable ACS P2P upstream forwarding */
2599 pci_enable_acs(dev);
2601 /* Precision Time Measurement */
2604 /* Advanced Error Reporting */
2607 pcie_report_downtraining(dev);
2609 if (pci_probe_reset_function(dev) == 0)
2614 * This is the equivalent of pci_host_bridge_msi_domain() that acts on
2615 * devices. Firmware interfaces that can select the MSI domain on a
2616 * per-device basis should be called from here.
2618 static struct irq_domain *pci_dev_msi_domain(struct pci_dev *dev)
2620 struct irq_domain *d;
2623 * If a domain has been set through the pcibios_add_device()
2624 * callback, then this is the one (platform code knows best).
2626 d = dev_get_msi_domain(&dev->dev);
2631 * Let's see if we have a firmware interface able to provide
2634 d = pci_msi_get_device_domain(dev);
2641 static void pci_set_msi_domain(struct pci_dev *dev)
2643 struct irq_domain *d;
2646 * If the platform or firmware interfaces cannot supply a
2647 * device-specific MSI domain, then inherit the default domain
2648 * from the host bridge itself.
2650 d = pci_dev_msi_domain(dev);
2652 d = dev_get_msi_domain(&dev->bus->dev);
2654 dev_set_msi_domain(&dev->dev, d);
2657 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
2661 pci_configure_device(dev);
2663 device_initialize(&dev->dev);
2664 dev->dev.release = pci_release_dev;
2666 set_dev_node(&dev->dev, pcibus_to_node(bus));
2667 dev->dev.dma_mask = &dev->dma_mask;
2668 dev->dev.dma_parms = &dev->dma_parms;
2669 dev->dev.coherent_dma_mask = 0xffffffffull;
2671 dma_set_max_seg_size(&dev->dev, 65536);
2672 dma_set_seg_boundary(&dev->dev, 0xffffffff);
2674 /* Fix up broken headers */
2675 pci_fixup_device(pci_fixup_header, dev);
2677 /* Moved out from quirk header fixup code */
2678 pci_reassigndev_resource_alignment(dev);
2680 /* Clear the state_saved flag */
2681 dev->state_saved = false;
2683 /* Initialize various capabilities */
2684 pci_init_capabilities(dev);
2687 * Add the device to our list of discovered devices
2688 * and the bus list for fixup functions, etc.
2690 down_write(&pci_bus_sem);
2691 list_add_tail(&dev->bus_list, &bus->devices);
2692 up_write(&pci_bus_sem);
2694 ret = pcibios_add_device(dev);
2697 /* Set up MSI IRQ domain */
2698 pci_set_msi_domain(dev);
2700 /* Notifier could use PCI capabilities */
2701 dev->match_driver = false;
2702 ret = device_add(&dev->dev);
2706 struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn)
2708 struct pci_dev *dev;
2710 dev = pci_get_slot(bus, devfn);
2716 dev = pci_scan_device(bus, devfn);
2720 pci_device_add(dev, bus);
2724 EXPORT_SYMBOL(pci_scan_single_device);
2726 static unsigned next_fn(struct pci_bus *bus, struct pci_dev *dev, unsigned fn)
2732 if (pci_ari_enabled(bus)) {
2735 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
2739 pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap);
2740 next_fn = PCI_ARI_CAP_NFN(cap);
2742 return 0; /* protect against malformed list */
2747 /* dev may be NULL for non-contiguous multifunction devices */
2748 if (!dev || dev->multifunction)
2749 return (fn + 1) % 8;
2754 static int only_one_child(struct pci_bus *bus)
2756 struct pci_dev *bridge = bus->self;
2759 * Systems with unusual topologies set PCI_SCAN_ALL_PCIE_DEVS so
2760 * we scan for all possible devices, not just Device 0.
2762 if (pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
2766 * A PCIe Downstream Port normally leads to a Link with only Device
2767 * 0 on it (PCIe spec r3.1, sec 7.3.1). As an optimization, scan
2768 * only for Device 0 in that situation.
2770 * Checking has_secondary_link is a hack to identify Downstream
2771 * Ports because sometimes Switches are configured such that the
2772 * PCIe Port Type labels are backwards.
2774 if (bridge && pci_is_pcie(bridge) && bridge->has_secondary_link)
2781 * pci_scan_slot - Scan a PCI slot on a bus for devices
2782 * @bus: PCI bus to scan
2783 * @devfn: slot number to scan (must have zero function)
2785 * Scan a PCI slot on the specified PCI bus for devices, adding
2786 * discovered devices to the @bus->devices list. New devices
2787 * will not have is_added set.
2789 * Returns the number of new devices found.
2791 int pci_scan_slot(struct pci_bus *bus, int devfn)
2793 unsigned fn, nr = 0;
2794 struct pci_dev *dev;
2796 if (only_one_child(bus) && (devfn > 0))
2797 return 0; /* Already scanned the entire slot */
2799 dev = pci_scan_single_device(bus, devfn);
2802 if (!pci_dev_is_added(dev))
2805 for (fn = next_fn(bus, dev, 0); fn > 0; fn = next_fn(bus, dev, fn)) {
2806 dev = pci_scan_single_device(bus, devfn + fn);
2808 if (!pci_dev_is_added(dev))
2810 dev->multifunction = 1;
2814 /* Only one slot has PCIe device */
2815 if (bus->self && nr)
2816 pcie_aspm_init_link_state(bus->self);
2820 EXPORT_SYMBOL(pci_scan_slot);
2822 static int pcie_find_smpss(struct pci_dev *dev, void *data)
2826 if (!pci_is_pcie(dev))
2830 * We don't have a way to change MPS settings on devices that have
2831 * drivers attached. A hot-added device might support only the minimum
2832 * MPS setting (MPS=128). Therefore, if the fabric contains a bridge
2833 * where devices may be hot-added, we limit the fabric MPS to 128 so
2834 * hot-added devices will work correctly.
2836 * However, if we hot-add a device to a slot directly below a Root
2837 * Port, it's impossible for there to be other existing devices below
2838 * the port. We don't limit the MPS in this case because we can
2839 * reconfigure MPS on both the Root Port and the hot-added device,
2840 * and there are no other devices involved.
2842 * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
2844 if (dev->is_hotplug_bridge &&
2845 pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
2848 if (*smpss > dev->pcie_mpss)
2849 *smpss = dev->pcie_mpss;
2854 static void pcie_write_mps(struct pci_dev *dev, int mps)
2858 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
2859 mps = 128 << dev->pcie_mpss;
2861 if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
2865 * For "Performance", the assumption is made that
2866 * downstream communication will never be larger than
2867 * the MRRS. So, the MPS only needs to be configured
2868 * for the upstream communication. This being the case,
2869 * walk from the top down and set the MPS of the child
2870 * to that of the parent bus.
2872 * Configure the device MPS with the smaller of the
2873 * device MPSS or the bridge MPS (which is assumed to be
2874 * properly configured at this point to the largest
2875 * allowable MPS based on its parent bus).
2877 mps = min(mps, pcie_get_mps(dev->bus->self));
2880 rc = pcie_set_mps(dev, mps);
2882 pci_err(dev, "Failed attempting to set the MPS\n");
2885 static void pcie_write_mrrs(struct pci_dev *dev)
2890 * In the "safe" case, do not configure the MRRS. There appear to be
2891 * issues with setting MRRS to 0 on a number of devices.
2893 if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
2897 * For max performance, the MRRS must be set to the largest supported
2898 * value. However, it cannot be configured larger than the MPS the
2899 * device or the bus can support. This should already be properly
2900 * configured by a prior call to pcie_write_mps().
2902 mrrs = pcie_get_mps(dev);
2905 * MRRS is a R/W register. Invalid values can be written, but a
2906 * subsequent read will verify if the value is acceptable or not.
2907 * If the MRRS value provided is not acceptable (e.g., too large),
2908 * shrink the value until it is acceptable to the HW.
2910 while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
2911 rc = pcie_set_readrq(dev, mrrs);
2915 pci_warn(dev, "Failed attempting to set the MRRS\n");
2920 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");
2923 static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
2927 if (!pci_is_pcie(dev))
2930 if (pcie_bus_config == PCIE_BUS_TUNE_OFF ||
2931 pcie_bus_config == PCIE_BUS_DEFAULT)
2934 mps = 128 << *(u8 *)data;
2935 orig_mps = pcie_get_mps(dev);
2937 pcie_write_mps(dev, mps);
2938 pcie_write_mrrs(dev);
2940 pci_info(dev, "Max Payload Size set to %4d/%4d (was %4d), Max Read Rq %4d\n",
2941 pcie_get_mps(dev), 128 << dev->pcie_mpss,
2942 orig_mps, pcie_get_readrq(dev));
2948 * pcie_bus_configure_settings() requires that pci_walk_bus work in a top-down,
2949 * parents then children fashion. If this changes, then this code will not
2952 void pcie_bus_configure_settings(struct pci_bus *bus)
2959 if (!pci_is_pcie(bus->self))
2963 * FIXME - Peer to peer DMA is possible, though the endpoint would need
2964 * to be aware of the MPS of the destination. To work around this,
2965 * simply force the MPS of the entire system to the smallest possible.
2967 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
2970 if (pcie_bus_config == PCIE_BUS_SAFE) {
2971 smpss = bus->self->pcie_mpss;
2973 pcie_find_smpss(bus->self, &smpss);
2974 pci_walk_bus(bus, pcie_find_smpss, &smpss);
2977 pcie_bus_configure_set(bus->self, &smpss);
2978 pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
2980 EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
2983 * Called after each bus is probed, but before its children are examined. This
2984 * is marked as __weak because multiple architectures define it.
2986 void __weak pcibios_fixup_bus(struct pci_bus *bus)
2988 /* nothing to do, expected to be removed in the future */
2992 * pci_scan_child_bus_extend() - Scan devices below a bus
2993 * @bus: Bus to scan for devices
2994 * @available_buses: Total number of buses available (%0 does not try to
2995 * extend beyond the minimal)
2997 * Scans devices below @bus including subordinate buses. Returns new
2998 * subordinate number including all the found devices. Passing
2999 * @available_buses causes the remaining bus space to be distributed
3000 * equally between hotplug-capable bridges to allow future extension of the
3003 static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
3004 unsigned int available_buses)
3006 unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0;
3007 unsigned int start = bus->busn_res.start;
3008 unsigned int devfn, fn, cmax, max = start;
3009 struct pci_dev *dev;
3012 dev_dbg(&bus->dev, "scanning bus\n");
3014 /* Go find them, Rover! */
3015 for (devfn = 0; devfn < 256; devfn += 8) {
3016 nr_devs = pci_scan_slot(bus, devfn);
3019 * The Jailhouse hypervisor may pass individual functions of a
3020 * multi-function device to a guest without passing function 0.
3021 * Look for them as well.
3023 if (jailhouse_paravirt() && nr_devs == 0) {
3024 for (fn = 1; fn < 8; fn++) {
3025 dev = pci_scan_single_device(bus, devfn + fn);
3027 dev->multifunction = 1;
3032 /* Reserve buses for SR-IOV capability */
3033 used_buses = pci_iov_bus_range(bus);
3037 * After performing arch-dependent fixup of the bus, look behind
3038 * all PCI-to-PCI bridges on this bus.
3040 if (!bus->is_added) {
3041 dev_dbg(&bus->dev, "fixups for bus\n");
3042 pcibios_fixup_bus(bus);
3047 * Calculate how many hotplug bridges and normal bridges there
3048 * are on this bus. We will distribute the additional available
3049 * buses between hotplug bridges.
3051 for_each_pci_bridge(dev, bus) {
3052 if (dev->is_hotplug_bridge)
3059 * Scan bridges that are already configured. We don't touch them
3060 * unless they are misconfigured (which will be done in the second
3063 for_each_pci_bridge(dev, bus) {
3065 max = pci_scan_bridge_extend(bus, dev, max, 0, 0);
3068 * Reserve one bus for each bridge now to avoid extending
3069 * hotplug bridges too much during the second scan below.
3073 used_buses += cmax - max - 1;
3076 /* Scan bridges that need to be reconfigured */
3077 for_each_pci_bridge(dev, bus) {
3078 unsigned int buses = 0;
3080 if (!hotplug_bridges && normal_bridges == 1) {
3083 * There is only one bridge on the bus (upstream
3084 * port) so it gets all available buses which it
3085 * can then distribute to the possible hotplug
3088 buses = available_buses;
3089 } else if (dev->is_hotplug_bridge) {
3092 * Distribute the extra buses between hotplug
3095 buses = available_buses / hotplug_bridges;
3096 buses = min(buses, available_buses - used_buses + 1);
3100 max = pci_scan_bridge_extend(bus, dev, cmax, buses, 1);
3101 /* One bus is already accounted so don't add it again */
3103 used_buses += max - cmax - 1;
3107 * Make sure a hotplug bridge has at least the minimum requested
3108 * number of buses but allow it to grow up to the maximum available
3109 * bus number of there is room.
3111 if (bus->self && bus->self->is_hotplug_bridge) {
3112 used_buses = max_t(unsigned int, available_buses,
3113 pci_hotplug_bus_size - 1);
3114 if (max - start < used_buses) {
3115 max = start + used_buses;
3117 /* Do not allocate more buses than we have room left */
3118 if (max > bus->busn_res.end)
3119 max = bus->busn_res.end;
3121 dev_dbg(&bus->dev, "%pR extended by %#02x\n",
3122 &bus->busn_res, max - start);
3127 * We've scanned the bus and so we know all about what's on
3128 * the other side of any bridges that may be on this bus plus
3131 * Return how far we've got finding sub-buses.
3133 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
3138 * pci_scan_child_bus() - Scan devices below a bus
3139 * @bus: Bus to scan for devices
3141 * Scans devices below @bus including subordinate buses. Returns new
3142 * subordinate number including all the found devices.
3144 unsigned int pci_scan_child_bus(struct pci_bus *bus)
3146 return pci_scan_child_bus_extend(bus, 0);
3148 EXPORT_SYMBOL_GPL(pci_scan_child_bus);
3151 * pcibios_root_bridge_prepare - Platform-specific host bridge setup
3152 * @bridge: Host bridge to set up
3154 * Default empty implementation. Replace with an architecture-specific setup
3155 * routine, if necessary.
3157 int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
3162 void __weak pcibios_add_bus(struct pci_bus *bus)
3166 void __weak pcibios_remove_bus(struct pci_bus *bus)
3170 struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
3171 struct pci_ops *ops, void *sysdata, struct list_head *resources)
3174 struct pci_host_bridge *bridge;
3176 bridge = pci_alloc_host_bridge(0);
3180 bridge->dev.parent = parent;
3182 list_splice_init(resources, &bridge->windows);
3183 bridge->sysdata = sysdata;
3184 bridge->busnr = bus;
3187 error = pci_register_host_bridge(bridge);
3197 EXPORT_SYMBOL_GPL(pci_create_root_bus);
3199 int pci_host_probe(struct pci_host_bridge *bridge)
3201 struct pci_bus *bus, *child;
3204 ret = pci_scan_root_bus_bridge(bridge);
3206 dev_err(bridge->dev.parent, "Scanning root bridge failed");
3213 * We insert PCI resources into the iomem_resource and
3214 * ioport_resource trees in either pci_bus_claim_resources()
3215 * or pci_bus_assign_resources().
3217 if (pci_has_flag(PCI_PROBE_ONLY)) {
3218 pci_bus_claim_resources(bus);
3220 pci_bus_size_bridges(bus);
3221 pci_bus_assign_resources(bus);
3223 list_for_each_entry(child, &bus->children, node)
3224 pcie_bus_configure_settings(child);
3227 pci_bus_add_devices(bus);
3230 EXPORT_SYMBOL_GPL(pci_host_probe);
3232 int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
3234 struct resource *res = &b->busn_res;
3235 struct resource *parent_res, *conflict;
3239 res->flags = IORESOURCE_BUS;
3241 if (!pci_is_root_bus(b))
3242 parent_res = &b->parent->busn_res;
3244 parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
3245 res->flags |= IORESOURCE_PCI_FIXED;
3248 conflict = request_resource_conflict(parent_res, res);
3252 "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
3253 res, pci_is_root_bus(b) ? "domain " : "",
3254 parent_res, conflict->name, conflict);
3256 return conflict == NULL;
3259 int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
3261 struct resource *res = &b->busn_res;
3262 struct resource old_res = *res;
3263 resource_size_t size;
3266 if (res->start > bus_max)
3269 size = bus_max - res->start + 1;
3270 ret = adjust_resource(res, res->start, size);
3271 dev_info(&b->dev, "busn_res: %pR end %s updated to %02x\n",
3272 &old_res, ret ? "can not be" : "is", bus_max);
3274 if (!ret && !res->parent)
3275 pci_bus_insert_busn_res(b, res->start, res->end);
3280 void pci_bus_release_busn_res(struct pci_bus *b)
3282 struct resource *res = &b->busn_res;
3285 if (!res->flags || !res->parent)
3288 ret = release_resource(res);
3289 dev_info(&b->dev, "busn_res: %pR %s released\n",
3290 res, ret ? "can not be" : "is");
3293 int pci_scan_root_bus_bridge(struct pci_host_bridge *bridge)
3295 struct resource_entry *window;
3303 resource_list_for_each_entry(window, &bridge->windows)
3304 if (window->res->flags & IORESOURCE_BUS) {
3309 ret = pci_register_host_bridge(bridge);
3314 bus = bridge->busnr;
3318 "No busn resource found for root bus, will use [bus %02x-ff]\n",
3320 pci_bus_insert_busn_res(b, bus, 255);
3323 max = pci_scan_child_bus(b);
3326 pci_bus_update_busn_res_end(b, max);
3330 EXPORT_SYMBOL(pci_scan_root_bus_bridge);
3332 struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
3333 struct pci_ops *ops, void *sysdata, struct list_head *resources)
3335 struct resource_entry *window;
3340 resource_list_for_each_entry(window, resources)
3341 if (window->res->flags & IORESOURCE_BUS) {
3346 b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
3352 "No busn resource found for root bus, will use [bus %02x-ff]\n",
3354 pci_bus_insert_busn_res(b, bus, 255);
3357 max = pci_scan_child_bus(b);
3360 pci_bus_update_busn_res_end(b, max);
3364 EXPORT_SYMBOL(pci_scan_root_bus);
3366 struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
3369 LIST_HEAD(resources);
3372 pci_add_resource(&resources, &ioport_resource);
3373 pci_add_resource(&resources, &iomem_resource);
3374 pci_add_resource(&resources, &busn_resource);
3375 b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
3377 pci_scan_child_bus(b);
3379 pci_free_resource_list(&resources);
3383 EXPORT_SYMBOL(pci_scan_bus);
3386 * pci_rescan_bus_bridge_resize - Scan a PCI bus for devices
3387 * @bridge: PCI bridge for the bus to scan
3389 * Scan a PCI bus and child buses for new devices, add them,
3390 * and enable them, resizing bridge mmio/io resource if necessary
3391 * and possible. The caller must ensure the child devices are already
3392 * removed for resizing to occur.
3394 * Returns the max number of subordinate bus discovered.
3396 unsigned int pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
3399 struct pci_bus *bus = bridge->subordinate;
3401 max = pci_scan_child_bus(bus);
3403 pci_assign_unassigned_bridge_resources(bridge);
3405 pci_bus_add_devices(bus);
3411 * pci_rescan_bus - Scan a PCI bus for devices
3412 * @bus: PCI bus to scan
3414 * Scan a PCI bus and child buses for new devices, add them,
3417 * Returns the max number of subordinate bus discovered.
3419 unsigned int pci_rescan_bus(struct pci_bus *bus)
3423 max = pci_scan_child_bus(bus);
3424 pci_assign_unassigned_bus_resources(bus);
3425 pci_bus_add_devices(bus);
3429 EXPORT_SYMBOL_GPL(pci_rescan_bus);
3432 * pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal
3433 * routines should always be executed under this mutex.
3435 static DEFINE_MUTEX(pci_rescan_remove_lock);
3437 void pci_lock_rescan_remove(void)
3439 mutex_lock(&pci_rescan_remove_lock);
3441 EXPORT_SYMBOL_GPL(pci_lock_rescan_remove);
3443 void pci_unlock_rescan_remove(void)
3445 mutex_unlock(&pci_rescan_remove_lock);
3447 EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove);
3449 static int __init pci_sort_bf_cmp(const struct device *d_a,
3450 const struct device *d_b)
3452 const struct pci_dev *a = to_pci_dev(d_a);
3453 const struct pci_dev *b = to_pci_dev(d_b);
3455 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
3456 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
3458 if (a->bus->number < b->bus->number) return -1;
3459 else if (a->bus->number > b->bus->number) return 1;
3461 if (a->devfn < b->devfn) return -1;
3462 else if (a->devfn > b->devfn) return 1;
3467 void __init pci_sort_breadthfirst(void)
3469 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);
3472 int pci_hp_add_bridge(struct pci_dev *dev)
3474 struct pci_bus *parent = dev->bus;
3475 int busnr, start = parent->busn_res.start;
3476 unsigned int available_buses = 0;
3477 int end = parent->busn_res.end;
3479 for (busnr = start; busnr <= end; busnr++) {
3480 if (!pci_find_bus(pci_domain_nr(parent), busnr))
3483 if (busnr-- > end) {
3484 pci_err(dev, "No bus number available for hot-added bridge\n");
3488 /* Scan bridges that are already configured */
3489 busnr = pci_scan_bridge(parent, dev, busnr, 0);
3492 * Distribute the available bus numbers between hotplug-capable
3493 * bridges to make extending the chain later possible.
3495 available_buses = end - busnr;
3497 /* Scan bridges that need to be reconfigured */
3498 pci_scan_bridge_extend(parent, dev, busnr, available_buses, 1);
3500 if (!dev->subordinate)
3505 EXPORT_SYMBOL_GPL(pci_hp_add_bridge);