2 * probe.c - PCI detection and setup code
5 #include <linux/kernel.h>
6 #include <linux/delay.h>
7 #include <linux/init.h>
9 #include <linux/slab.h>
10 #include <linux/module.h>
11 #include <linux/cpumask.h>
12 #include <linux/pci-aspm.h>
13 #include <asm-generic/pci-bridge.h>
16 #define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
17 #define CARDBUS_RESERVE_BUSNR 3
19 static struct resource busn_resource = {
23 .flags = IORESOURCE_BUS,
26 /* Ugh. Need to stop exporting this to modules. */
27 LIST_HEAD(pci_root_buses);
28 EXPORT_SYMBOL(pci_root_buses);
30 static LIST_HEAD(pci_domain_busn_res_list);
32 struct pci_domain_busn_res {
33 struct list_head list;
38 static struct resource *get_pci_domain_busn_res(int domain_nr)
40 struct pci_domain_busn_res *r;
42 list_for_each_entry(r, &pci_domain_busn_res_list, list)
43 if (r->domain_nr == domain_nr)
46 r = kzalloc(sizeof(*r), GFP_KERNEL);
50 r->domain_nr = domain_nr;
53 r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
55 list_add_tail(&r->list, &pci_domain_busn_res_list);
60 static int find_anything(struct device *dev, void *data)
66 * Some device drivers need know if pci is initiated.
67 * Basically, we think pci is not initiated when there
68 * is no device to be found on the pci_bus_type.
70 int no_pci_devices(void)
75 dev = bus_find_device(&pci_bus_type, NULL, NULL, find_anything);
76 no_devices = (dev == NULL);
80 EXPORT_SYMBOL(no_pci_devices);
85 static void release_pcibus_dev(struct device *dev)
87 struct pci_bus *pci_bus = to_pci_bus(dev);
90 put_device(pci_bus->bridge);
91 pci_bus_remove_resources(pci_bus);
92 pci_release_bus_of_node(pci_bus);
96 static struct class pcibus_class = {
98 .dev_release = &release_pcibus_dev,
99 .dev_groups = pcibus_groups,
102 static int __init pcibus_class_init(void)
104 return class_register(&pcibus_class);
106 postcore_initcall(pcibus_class_init);
108 static u64 pci_size(u64 base, u64 maxbase, u64 mask)
110 u64 size = mask & maxbase; /* Find the significant bits */
114 /* Get the lowest of them to find the decode size, and
115 from that the extent. */
116 size = (size & ~(size-1)) - 1;
118 /* base == maxbase can be valid only if the BAR has
119 already been programmed with all 1s. */
120 if (base == maxbase && ((base | size) & mask) != mask)
126 static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
131 if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
132 flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
133 flags |= IORESOURCE_IO;
137 flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
138 flags |= IORESOURCE_MEM;
139 if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
140 flags |= IORESOURCE_PREFETCH;
142 mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
144 case PCI_BASE_ADDRESS_MEM_TYPE_32:
146 case PCI_BASE_ADDRESS_MEM_TYPE_1M:
147 /* 1M mem BAR treated as 32-bit BAR */
149 case PCI_BASE_ADDRESS_MEM_TYPE_64:
150 flags |= IORESOURCE_MEM_64;
153 /* mem unknown type treated as 32-bit BAR */
159 #define PCI_COMMAND_DECODE_ENABLE (PCI_COMMAND_MEMORY | PCI_COMMAND_IO)
162 * pci_read_base - read a PCI BAR
163 * @dev: the PCI device
164 * @type: type of the BAR
165 * @res: resource buffer to be filled in
166 * @pos: BAR position in the config space
168 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
170 int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
171 struct resource *res, unsigned int pos)
174 u64 l64, sz64, mask64;
176 struct pci_bus_region region, inverted_region;
177 bool bar_too_big = false, bar_too_high = false, bar_invalid = false;
179 mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
181 /* No printks while decoding is disabled! */
182 if (!dev->mmio_always_on) {
183 pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
184 if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) {
185 pci_write_config_word(dev, PCI_COMMAND,
186 orig_cmd & ~PCI_COMMAND_DECODE_ENABLE);
190 res->name = pci_name(dev);
192 pci_read_config_dword(dev, pos, &l);
193 pci_write_config_dword(dev, pos, l | mask);
194 pci_read_config_dword(dev, pos, &sz);
195 pci_write_config_dword(dev, pos, l);
198 * All bits set in sz means the device isn't working properly.
199 * If the BAR isn't implemented, all bits must be 0. If it's a
200 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
203 if (!sz || sz == 0xffffffff)
207 * I don't know how l can have all bits set. Copied from old code.
208 * Maybe it fixes a bug on some ancient platform.
213 if (type == pci_bar_unknown) {
214 res->flags = decode_bar(dev, l);
215 res->flags |= IORESOURCE_SIZEALIGN;
216 if (res->flags & IORESOURCE_IO) {
217 l &= PCI_BASE_ADDRESS_IO_MASK;
218 mask = PCI_BASE_ADDRESS_IO_MASK & (u32) IO_SPACE_LIMIT;
220 l &= PCI_BASE_ADDRESS_MEM_MASK;
221 mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
224 res->flags |= (l & IORESOURCE_ROM_ENABLE);
225 l &= PCI_ROM_ADDRESS_MASK;
226 mask = (u32)PCI_ROM_ADDRESS_MASK;
229 if (res->flags & IORESOURCE_MEM_64) {
232 mask64 = mask | (u64)~0 << 32;
234 pci_read_config_dword(dev, pos + 4, &l);
235 pci_write_config_dword(dev, pos + 4, ~0);
236 pci_read_config_dword(dev, pos + 4, &sz);
237 pci_write_config_dword(dev, pos + 4, l);
239 l64 |= ((u64)l << 32);
240 sz64 |= ((u64)sz << 32);
242 sz64 = pci_size(l64, sz64, mask64);
247 if ((sizeof(dma_addr_t) < 8 || sizeof(resource_size_t) < 8) &&
248 sz64 > 0x100000000ULL) {
249 res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
256 if ((sizeof(dma_addr_t) < 8) && l) {
257 /* Above 32-bit boundary; try to reallocate */
258 res->flags |= IORESOURCE_UNSET;
265 region.end = l64 + sz64;
268 sz = pci_size(l, sz, mask);
277 pcibios_bus_to_resource(dev->bus, res, ®ion);
278 pcibios_resource_to_bus(dev->bus, &inverted_region, res);
281 * If "A" is a BAR value (a bus address), "bus_to_resource(A)" is
282 * the corresponding resource address (the physical address used by
283 * the CPU. Converting that resource address back to a bus address
284 * should yield the original BAR value:
286 * resource_to_bus(bus_to_resource(A)) == A
288 * If it doesn't, CPU accesses to "bus_to_resource(A)" will not
289 * be claimed by the device.
291 if (inverted_region.start != region.start) {
292 res->flags |= IORESOURCE_UNSET;
294 res->end = region.end - region.start;
304 if (!dev->mmio_always_on &&
305 (orig_cmd & PCI_COMMAND_DECODE_ENABLE))
306 pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
309 dev_err(&dev->dev, "reg 0x%x: can't handle BAR larger than 4GB (size %#010llx)\n",
310 pos, (unsigned long long) sz64);
312 dev_info(&dev->dev, "reg 0x%x: can't handle BAR above 4G (bus address %#010llx)\n",
313 pos, (unsigned long long) l64);
315 dev_info(&dev->dev, "reg 0x%x: initial BAR value %#010llx invalid\n",
316 pos, (unsigned long long) region.start);
318 dev_printk(KERN_DEBUG, &dev->dev, "reg 0x%x: %pR\n", pos, res);
320 return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
323 static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
325 unsigned int pos, reg;
327 for (pos = 0; pos < howmany; pos++) {
328 struct resource *res = &dev->resource[pos];
329 reg = PCI_BASE_ADDRESS_0 + (pos << 2);
330 pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
334 struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
335 dev->rom_base_reg = rom;
336 res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
337 IORESOURCE_READONLY | IORESOURCE_CACHEABLE |
338 IORESOURCE_SIZEALIGN;
339 __pci_read_base(dev, pci_bar_mem32, res, rom);
343 static void pci_read_bridge_io(struct pci_bus *child)
345 struct pci_dev *dev = child->self;
346 u8 io_base_lo, io_limit_lo;
347 unsigned long io_mask, io_granularity, base, limit;
348 struct pci_bus_region region;
349 struct resource *res;
351 io_mask = PCI_IO_RANGE_MASK;
352 io_granularity = 0x1000;
353 if (dev->io_window_1k) {
354 /* Support 1K I/O space granularity */
355 io_mask = PCI_IO_1K_RANGE_MASK;
356 io_granularity = 0x400;
359 res = child->resource[0];
360 pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
361 pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
362 base = (io_base_lo & io_mask) << 8;
363 limit = (io_limit_lo & io_mask) << 8;
365 if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
366 u16 io_base_hi, io_limit_hi;
368 pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
369 pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
370 base |= ((unsigned long) io_base_hi << 16);
371 limit |= ((unsigned long) io_limit_hi << 16);
375 res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
377 region.end = limit + io_granularity - 1;
378 pcibios_bus_to_resource(dev->bus, res, ®ion);
379 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
383 static void pci_read_bridge_mmio(struct pci_bus *child)
385 struct pci_dev *dev = child->self;
386 u16 mem_base_lo, mem_limit_lo;
387 unsigned long base, limit;
388 struct pci_bus_region region;
389 struct resource *res;
391 res = child->resource[1];
392 pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
393 pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
394 base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
395 limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
397 res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
399 region.end = limit + 0xfffff;
400 pcibios_bus_to_resource(dev->bus, res, ®ion);
401 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
405 static void pci_read_bridge_mmio_pref(struct pci_bus *child)
407 struct pci_dev *dev = child->self;
408 u16 mem_base_lo, mem_limit_lo;
409 unsigned long base, limit;
410 struct pci_bus_region region;
411 struct resource *res;
413 res = child->resource[2];
414 pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
415 pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
416 base = ((unsigned long) mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
417 limit = ((unsigned long) mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
419 if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
420 u32 mem_base_hi, mem_limit_hi;
422 pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
423 pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
426 * Some bridges set the base > limit by default, and some
427 * (broken) BIOSes do not initialize them. If we find
428 * this, just assume they are not being used.
430 if (mem_base_hi <= mem_limit_hi) {
431 #if BITS_PER_LONG == 64
432 base |= ((unsigned long) mem_base_hi) << 32;
433 limit |= ((unsigned long) mem_limit_hi) << 32;
435 if (mem_base_hi || mem_limit_hi) {
436 dev_err(&dev->dev, "can't handle 64-bit "
437 "address space for bridge\n");
444 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
445 IORESOURCE_MEM | IORESOURCE_PREFETCH;
446 if (res->flags & PCI_PREF_RANGE_TYPE_64)
447 res->flags |= IORESOURCE_MEM_64;
449 region.end = limit + 0xfffff;
450 pcibios_bus_to_resource(dev->bus, res, ®ion);
451 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
455 void pci_read_bridge_bases(struct pci_bus *child)
457 struct pci_dev *dev = child->self;
458 struct resource *res;
461 if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
464 dev_info(&dev->dev, "PCI bridge to %pR%s\n",
466 dev->transparent ? " (subtractive decode)" : "");
468 pci_bus_remove_resources(child);
469 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
470 child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
472 pci_read_bridge_io(child);
473 pci_read_bridge_mmio(child);
474 pci_read_bridge_mmio_pref(child);
476 if (dev->transparent) {
477 pci_bus_for_each_resource(child->parent, res, i) {
478 if (res && res->flags) {
479 pci_bus_add_resource(child, res,
480 PCI_SUBTRACTIVE_DECODE);
481 dev_printk(KERN_DEBUG, &dev->dev,
482 " bridge window %pR (subtractive decode)\n",
489 static struct pci_bus *pci_alloc_bus(void)
493 b = kzalloc(sizeof(*b), GFP_KERNEL);
497 INIT_LIST_HEAD(&b->node);
498 INIT_LIST_HEAD(&b->children);
499 INIT_LIST_HEAD(&b->devices);
500 INIT_LIST_HEAD(&b->slots);
501 INIT_LIST_HEAD(&b->resources);
502 b->max_bus_speed = PCI_SPEED_UNKNOWN;
503 b->cur_bus_speed = PCI_SPEED_UNKNOWN;
507 static void pci_release_host_bridge_dev(struct device *dev)
509 struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
511 if (bridge->release_fn)
512 bridge->release_fn(bridge);
514 pci_free_resource_list(&bridge->windows);
519 static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b)
521 struct pci_host_bridge *bridge;
523 bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
527 INIT_LIST_HEAD(&bridge->windows);
532 static const unsigned char pcix_bus_speed[] = {
533 PCI_SPEED_UNKNOWN, /* 0 */
534 PCI_SPEED_66MHz_PCIX, /* 1 */
535 PCI_SPEED_100MHz_PCIX, /* 2 */
536 PCI_SPEED_133MHz_PCIX, /* 3 */
537 PCI_SPEED_UNKNOWN, /* 4 */
538 PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
539 PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
540 PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
541 PCI_SPEED_UNKNOWN, /* 8 */
542 PCI_SPEED_66MHz_PCIX_266, /* 9 */
543 PCI_SPEED_100MHz_PCIX_266, /* A */
544 PCI_SPEED_133MHz_PCIX_266, /* B */
545 PCI_SPEED_UNKNOWN, /* C */
546 PCI_SPEED_66MHz_PCIX_533, /* D */
547 PCI_SPEED_100MHz_PCIX_533, /* E */
548 PCI_SPEED_133MHz_PCIX_533 /* F */
551 const unsigned char pcie_link_speed[] = {
552 PCI_SPEED_UNKNOWN, /* 0 */
553 PCIE_SPEED_2_5GT, /* 1 */
554 PCIE_SPEED_5_0GT, /* 2 */
555 PCIE_SPEED_8_0GT, /* 3 */
556 PCI_SPEED_UNKNOWN, /* 4 */
557 PCI_SPEED_UNKNOWN, /* 5 */
558 PCI_SPEED_UNKNOWN, /* 6 */
559 PCI_SPEED_UNKNOWN, /* 7 */
560 PCI_SPEED_UNKNOWN, /* 8 */
561 PCI_SPEED_UNKNOWN, /* 9 */
562 PCI_SPEED_UNKNOWN, /* A */
563 PCI_SPEED_UNKNOWN, /* B */
564 PCI_SPEED_UNKNOWN, /* C */
565 PCI_SPEED_UNKNOWN, /* D */
566 PCI_SPEED_UNKNOWN, /* E */
567 PCI_SPEED_UNKNOWN /* F */
570 void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
572 bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS];
574 EXPORT_SYMBOL_GPL(pcie_update_link_speed);
576 static unsigned char agp_speeds[] = {
584 static enum pci_bus_speed agp_speed(int agp3, int agpstat)
590 else if (agpstat & 2)
592 else if (agpstat & 1)
604 return agp_speeds[index];
608 static void pci_set_bus_speed(struct pci_bus *bus)
610 struct pci_dev *bridge = bus->self;
613 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
615 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
619 pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
620 bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
622 pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
623 bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
626 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
629 enum pci_bus_speed max;
631 pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
634 if (status & PCI_X_SSTATUS_533MHZ) {
635 max = PCI_SPEED_133MHz_PCIX_533;
636 } else if (status & PCI_X_SSTATUS_266MHZ) {
637 max = PCI_SPEED_133MHz_PCIX_266;
638 } else if (status & PCI_X_SSTATUS_133MHZ) {
639 if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2) {
640 max = PCI_SPEED_133MHz_PCIX_ECC;
642 max = PCI_SPEED_133MHz_PCIX;
645 max = PCI_SPEED_66MHz_PCIX;
648 bus->max_bus_speed = max;
649 bus->cur_bus_speed = pcix_bus_speed[
650 (status & PCI_X_SSTATUS_FREQ) >> 6];
655 if (pci_is_pcie(bridge)) {
659 pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
660 bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
662 pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
663 pcie_update_link_speed(bus, linksta);
668 static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
669 struct pci_dev *bridge, int busnr)
671 struct pci_bus *child;
676 * Allocate a new bus, and inherit stuff from the parent..
678 child = pci_alloc_bus();
682 child->parent = parent;
683 child->ops = parent->ops;
684 child->msi = parent->msi;
685 child->sysdata = parent->sysdata;
686 child->bus_flags = parent->bus_flags;
688 /* initialize some portions of the bus device, but don't register it
689 * now as the parent is not properly set up yet.
691 child->dev.class = &pcibus_class;
692 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
695 * Set up the primary, secondary and subordinate
698 child->number = child->busn_res.start = busnr;
699 child->primary = parent->busn_res.start;
700 child->busn_res.end = 0xff;
703 child->dev.parent = parent->bridge;
707 child->self = bridge;
708 child->bridge = get_device(&bridge->dev);
709 child->dev.parent = child->bridge;
710 pci_set_bus_of_node(child);
711 pci_set_bus_speed(child);
713 /* Set up default resource pointers and names.. */
714 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
715 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
716 child->resource[i]->name = child->name;
718 bridge->subordinate = child;
721 ret = device_register(&child->dev);
724 pcibios_add_bus(child);
726 /* Create legacy_io and legacy_mem files for this bus */
727 pci_create_legacy_files(child);
732 struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr)
734 struct pci_bus *child;
736 child = pci_alloc_child_bus(parent, dev, busnr);
738 down_write(&pci_bus_sem);
739 list_add_tail(&child->node, &parent->children);
740 up_write(&pci_bus_sem);
744 EXPORT_SYMBOL(pci_add_new_bus);
747 * If it's a bridge, configure it and scan the bus behind it.
748 * For CardBus bridges, we don't scan behind as the devices will
749 * be handled by the bridge driver itself.
751 * We need to process bridges in two passes -- first we scan those
752 * already configured by the BIOS and after we are done with all of
753 * them, we proceed to assigning numbers to the remaining buses in
754 * order to avoid overlaps between old and new bus numbers.
756 int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
758 struct pci_bus *child;
759 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
762 u8 primary, secondary, subordinate;
765 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
766 primary = buses & 0xFF;
767 secondary = (buses >> 8) & 0xFF;
768 subordinate = (buses >> 16) & 0xFF;
770 dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
771 secondary, subordinate, pass);
773 if (!primary && (primary != bus->number) && secondary && subordinate) {
774 dev_warn(&dev->dev, "Primary bus is hard wired to 0\n");
775 primary = bus->number;
778 /* Check if setup is sensible at all */
780 (primary != bus->number || secondary <= bus->number ||
781 secondary > subordinate || subordinate > bus->busn_res.end)) {
782 dev_info(&dev->dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
783 secondary, subordinate);
787 /* Disable MasterAbortMode during probing to avoid reporting
788 of bus errors (in some architectures) */
789 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
790 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
791 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
793 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
794 !is_cardbus && !broken) {
797 * Bus already configured by firmware, process it in the first
798 * pass and just note the configuration.
804 * The bus might already exist for two reasons: Either we are
805 * rescanning the bus or the bus is reachable through more than
806 * one bridge. The second case can happen with the i450NX
809 child = pci_find_bus(pci_domain_nr(bus), secondary);
811 child = pci_add_new_bus(bus, dev, secondary);
814 child->primary = primary;
815 pci_bus_insert_busn_res(child, secondary, subordinate);
816 child->bridge_ctl = bctl;
819 cmax = pci_scan_child_bus(child);
820 if (cmax > subordinate)
821 dev_warn(&dev->dev, "bridge has subordinate %02x but max busn %02x\n",
823 /* subordinate should equal child->busn_res.end */
824 if (subordinate > max)
828 * We need to assign a number to this bus which we always
829 * do in the second pass.
832 if (pcibios_assign_all_busses() || broken || is_cardbus)
833 /* Temporarily disable forwarding of the
834 configuration cycles on all bridges in
835 this bus segment to avoid possible
836 conflicts in the second pass between two
837 bridges programmed with overlapping
839 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
844 if (max >= bus->busn_res.end) {
845 dev_warn(&dev->dev, "can't allocate child bus %02x from %pR\n",
846 max, &bus->busn_res);
851 pci_write_config_word(dev, PCI_STATUS, 0xffff);
853 /* The bus will already exist if we are rescanning */
854 child = pci_find_bus(pci_domain_nr(bus), max+1);
856 child = pci_add_new_bus(bus, dev, max+1);
859 pci_bus_insert_busn_res(child, max+1,
863 buses = (buses & 0xff000000)
864 | ((unsigned int)(child->primary) << 0)
865 | ((unsigned int)(child->busn_res.start) << 8)
866 | ((unsigned int)(child->busn_res.end) << 16);
869 * yenta.c forces a secondary latency timer of 176.
870 * Copy that behaviour here.
873 buses &= ~0xff000000;
874 buses |= CARDBUS_LATENCY_TIMER << 24;
878 * We need to blast all three values with a single write.
880 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
883 child->bridge_ctl = bctl;
884 max = pci_scan_child_bus(child);
887 * For CardBus bridges, we leave 4 bus numbers
888 * as cards with a PCI-to-PCI bridge can be
891 for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
892 struct pci_bus *parent = bus;
893 if (pci_find_bus(pci_domain_nr(bus),
896 while (parent->parent) {
897 if ((!pcibios_assign_all_busses()) &&
898 (parent->busn_res.end > max) &&
899 (parent->busn_res.end <= max+i)) {
902 parent = parent->parent;
906 * Often, there are two cardbus bridges
907 * -- try to leave one valid bus number
917 * Set the subordinate bus number to its real value.
919 if (max > bus->busn_res.end) {
920 dev_warn(&dev->dev, "max busn %02x is outside %pR\n",
921 max, &bus->busn_res);
922 max = bus->busn_res.end;
924 pci_bus_update_busn_res_end(child, max);
925 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
929 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
930 pci_domain_nr(bus), child->number);
932 /* Has only triggered on CardBus, fixup is in yenta_socket */
933 while (bus->parent) {
934 if ((child->busn_res.end > bus->busn_res.end) ||
935 (child->number > bus->busn_res.end) ||
936 (child->number < bus->number) ||
937 (child->busn_res.end < bus->number)) {
938 dev_info(&child->dev, "%pR %s "
939 "hidden behind%s bridge %s %pR\n",
941 (bus->number > child->busn_res.end &&
942 bus->busn_res.end < child->number) ?
943 "wholly" : "partially",
944 bus->self->transparent ? " transparent" : "",
952 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
956 EXPORT_SYMBOL(pci_scan_bridge);
959 * Read interrupt line and base address registers.
960 * The architecture-dependent code can tweak these, of course.
962 static void pci_read_irq(struct pci_dev *dev)
966 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
969 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
973 void set_pcie_port_type(struct pci_dev *pdev)
978 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
981 pdev->pcie_cap = pos;
982 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
983 pdev->pcie_flags_reg = reg16;
984 pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16);
985 pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
988 void set_pcie_hotplug_bridge(struct pci_dev *pdev)
992 pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32);
993 if (reg32 & PCI_EXP_SLTCAP_HPC)
994 pdev->is_hotplug_bridge = 1;
999 * pci_ext_cfg_is_aliased - is ext config space just an alias of std config?
1002 * PCI Express to PCI/PCI-X Bridge Specification, rev 1.0, 4.1.4 says that
1003 * when forwarding a type1 configuration request the bridge must check that
1004 * the extended register address field is zero. The bridge is not permitted
1005 * to forward the transactions and must handle it as an Unsupported Request.
1006 * Some bridges do not follow this rule and simply drop the extended register
1007 * bits, resulting in the standard config space being aliased, every 256
1008 * bytes across the entire configuration space. Test for this condition by
1009 * comparing the first dword of each potential alias to the vendor/device ID.
1011 * ASM1083/1085 PCIe-to-PCI Reversible Bridge (1b21:1080, rev 01 & 03)
1012 * AMD/ATI SBx00 PCI to PCI Bridge (1002:4384, rev 40)
1014 static bool pci_ext_cfg_is_aliased(struct pci_dev *dev)
1016 #ifdef CONFIG_PCI_QUIRKS
1020 pci_read_config_dword(dev, PCI_VENDOR_ID, &header);
1022 for (pos = PCI_CFG_SPACE_SIZE;
1023 pos < PCI_CFG_SPACE_EXP_SIZE; pos += PCI_CFG_SPACE_SIZE) {
1024 if (pci_read_config_dword(dev, pos, &tmp) != PCIBIOS_SUCCESSFUL
1036 * pci_cfg_space_size - get the configuration space size of the PCI device.
1039 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1040 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1041 * access it. Maybe we don't have a way to generate extended config space
1042 * accesses, or the device is behind a reverse Express bridge. So we try
1043 * reading the dword at 0x100 which must either be 0 or a valid extended
1044 * capability header.
1046 static int pci_cfg_space_size_ext(struct pci_dev *dev)
1049 int pos = PCI_CFG_SPACE_SIZE;
1051 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1053 if (status == 0xffffffff || pci_ext_cfg_is_aliased(dev))
1056 return PCI_CFG_SPACE_EXP_SIZE;
1059 return PCI_CFG_SPACE_SIZE;
1062 int pci_cfg_space_size(struct pci_dev *dev)
1068 class = dev->class >> 8;
1069 if (class == PCI_CLASS_BRIDGE_HOST)
1070 return pci_cfg_space_size_ext(dev);
1072 if (!pci_is_pcie(dev)) {
1073 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1077 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1078 if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
1082 return pci_cfg_space_size_ext(dev);
1085 return PCI_CFG_SPACE_SIZE;
1088 #define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
1091 * pci_setup_device - fill in class and map information of a device
1092 * @dev: the device structure to fill
1094 * Initialize the device structure with information about the device's
1095 * vendor,class,memory and IO-space addresses,IRQ lines etc.
1096 * Called at initialisation of the PCI subsystem and by CardBus services.
1097 * Returns 0 on success and negative if unknown type of device (not normal,
1098 * bridge or CardBus).
1100 int pci_setup_device(struct pci_dev *dev)
1104 struct pci_slot *slot;
1106 struct pci_bus_region region;
1107 struct resource *res;
1109 if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
1112 dev->sysdata = dev->bus->sysdata;
1113 dev->dev.parent = dev->bus->bridge;
1114 dev->dev.bus = &pci_bus_type;
1115 dev->hdr_type = hdr_type & 0x7f;
1116 dev->multifunction = !!(hdr_type & 0x80);
1117 dev->error_state = pci_channel_io_normal;
1118 set_pcie_port_type(dev);
1120 list_for_each_entry(slot, &dev->bus->slots, list)
1121 if (PCI_SLOT(dev->devfn) == slot->number)
1124 /* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
1125 set this higher, assuming the system even supports it. */
1126 dev->dma_mask = 0xffffffff;
1128 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
1129 dev->bus->number, PCI_SLOT(dev->devfn),
1130 PCI_FUNC(dev->devfn));
1132 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
1133 dev->revision = class & 0xff;
1134 dev->class = class >> 8; /* upper 3 bytes */
1136 dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %02x class %#08x\n",
1137 dev->vendor, dev->device, dev->hdr_type, dev->class);
1139 /* need to have dev->class ready */
1140 dev->cfg_size = pci_cfg_space_size(dev);
1142 /* "Unknown power state" */
1143 dev->current_state = PCI_UNKNOWN;
1145 /* Early fixups, before probing the BARs */
1146 pci_fixup_device(pci_fixup_early, dev);
1147 /* device class may be changed after fixup */
1148 class = dev->class >> 8;
1150 switch (dev->hdr_type) { /* header type */
1151 case PCI_HEADER_TYPE_NORMAL: /* standard header */
1152 if (class == PCI_CLASS_BRIDGE_PCI)
1155 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1156 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1157 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
1160 * Do the ugly legacy mode stuff here rather than broken chip
1161 * quirk code. Legacy mode ATA controllers have fixed
1162 * addresses. These are not always echoed in BAR0-3, and
1163 * BAR0-3 in a few cases contain junk!
1165 if (class == PCI_CLASS_STORAGE_IDE) {
1167 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1168 if ((progif & 1) == 0) {
1169 region.start = 0x1F0;
1171 res = &dev->resource[0];
1172 res->flags = LEGACY_IO_RESOURCE;
1173 pcibios_bus_to_resource(dev->bus, res, ®ion);
1174 dev_info(&dev->dev, "legacy IDE quirk: reg 0x10: %pR\n",
1176 region.start = 0x3F6;
1178 res = &dev->resource[1];
1179 res->flags = LEGACY_IO_RESOURCE;
1180 pcibios_bus_to_resource(dev->bus, res, ®ion);
1181 dev_info(&dev->dev, "legacy IDE quirk: reg 0x14: %pR\n",
1184 if ((progif & 4) == 0) {
1185 region.start = 0x170;
1187 res = &dev->resource[2];
1188 res->flags = LEGACY_IO_RESOURCE;
1189 pcibios_bus_to_resource(dev->bus, res, ®ion);
1190 dev_info(&dev->dev, "legacy IDE quirk: reg 0x18: %pR\n",
1192 region.start = 0x376;
1194 res = &dev->resource[3];
1195 res->flags = LEGACY_IO_RESOURCE;
1196 pcibios_bus_to_resource(dev->bus, res, ®ion);
1197 dev_info(&dev->dev, "legacy IDE quirk: reg 0x1c: %pR\n",
1203 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1204 if (class != PCI_CLASS_BRIDGE_PCI)
1206 /* The PCI-to-PCI bridge spec requires that subtractive
1207 decoding (i.e. transparent) bridge must have programming
1208 interface code of 0x01. */
1210 dev->transparent = ((dev->class & 0xff) == 1);
1211 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1212 set_pcie_hotplug_bridge(dev);
1213 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1215 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1216 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1220 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1221 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1224 pci_read_bases(dev, 1, 0);
1225 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1226 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1229 default: /* unknown header */
1230 dev_err(&dev->dev, "unknown header type %02x, "
1231 "ignoring device\n", dev->hdr_type);
1235 dev_err(&dev->dev, "ignoring class %#08x (doesn't match header "
1236 "type %02x)\n", dev->class, dev->hdr_type);
1237 dev->class = PCI_CLASS_NOT_DEFINED;
1240 /* We found a fine healthy device, go go go... */
1244 static void pci_release_capabilities(struct pci_dev *dev)
1246 pci_vpd_release(dev);
1247 pci_iov_release(dev);
1248 pci_free_cap_save_buffers(dev);
1252 * pci_release_dev - free a pci device structure when all users of it are finished.
1253 * @dev: device that's been disconnected
1255 * Will be called only by the device core when all users of this pci device are
1258 static void pci_release_dev(struct device *dev)
1260 struct pci_dev *pci_dev;
1262 pci_dev = to_pci_dev(dev);
1263 pci_release_capabilities(pci_dev);
1264 pci_release_of_node(pci_dev);
1265 pcibios_release_device(pci_dev);
1266 pci_bus_put(pci_dev->bus);
1267 kfree(pci_dev->driver_override);
1271 struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
1273 struct pci_dev *dev;
1275 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
1279 INIT_LIST_HEAD(&dev->bus_list);
1280 dev->dev.type = &pci_dev_type;
1281 dev->bus = pci_bus_get(bus);
1285 EXPORT_SYMBOL(pci_alloc_dev);
1287 bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
1292 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1295 /* some broken boards return 0 or ~0 if a slot is empty: */
1296 if (*l == 0xffffffff || *l == 0x00000000 ||
1297 *l == 0x0000ffff || *l == 0xffff0000)
1300 /* Configuration request Retry Status */
1301 while (*l == 0xffff0001) {
1307 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1309 /* Card hasn't responded in 60 seconds? Must be stuck. */
1310 if (delay > crs_timeout) {
1311 printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not "
1312 "responding\n", pci_domain_nr(bus),
1313 bus->number, PCI_SLOT(devfn),
1321 EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
1324 * Read the config data for a PCI device, sanity-check it
1325 * and fill in the dev structure...
1327 static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
1329 struct pci_dev *dev;
1332 if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
1335 dev = pci_alloc_dev(bus);
1340 dev->vendor = l & 0xffff;
1341 dev->device = (l >> 16) & 0xffff;
1343 pci_set_of_node(dev);
1345 if (pci_setup_device(dev)) {
1346 pci_bus_put(dev->bus);
1354 static void pci_init_capabilities(struct pci_dev *dev)
1356 /* MSI/MSI-X list */
1357 pci_msi_init_pci_dev(dev);
1359 /* Buffers for saving PCIe and PCI-X capabilities */
1360 pci_allocate_cap_save_buffers(dev);
1362 /* Power Management */
1365 /* Vital Product Data */
1366 pci_vpd_pci22_init(dev);
1368 /* Alternative Routing-ID Forwarding */
1369 pci_configure_ari(dev);
1371 /* Single Root I/O Virtualization */
1374 /* Enable ACS P2P upstream forwarding */
1375 pci_enable_acs(dev);
1378 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
1382 device_initialize(&dev->dev);
1383 dev->dev.release = pci_release_dev;
1385 set_dev_node(&dev->dev, pcibus_to_node(bus));
1386 dev->dev.dma_mask = &dev->dma_mask;
1387 dev->dev.dma_parms = &dev->dma_parms;
1388 dev->dev.coherent_dma_mask = 0xffffffffull;
1390 pci_set_dma_max_seg_size(dev, 65536);
1391 pci_set_dma_seg_boundary(dev, 0xffffffff);
1393 /* Fix up broken headers */
1394 pci_fixup_device(pci_fixup_header, dev);
1396 /* moved out from quirk header fixup code */
1397 pci_reassigndev_resource_alignment(dev);
1399 /* Clear the state_saved flag. */
1400 dev->state_saved = false;
1402 /* Initialize various capabilities */
1403 pci_init_capabilities(dev);
1406 * Add the device to our list of discovered devices
1407 * and the bus list for fixup functions, etc.
1409 down_write(&pci_bus_sem);
1410 list_add_tail(&dev->bus_list, &bus->devices);
1411 up_write(&pci_bus_sem);
1413 ret = pcibios_add_device(dev);
1416 /* Notifier could use PCI capabilities */
1417 dev->match_driver = false;
1418 ret = device_add(&dev->dev);
1422 struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn)
1424 struct pci_dev *dev;
1426 dev = pci_get_slot(bus, devfn);
1432 dev = pci_scan_device(bus, devfn);
1436 pci_device_add(dev, bus);
1440 EXPORT_SYMBOL(pci_scan_single_device);
1442 static unsigned next_fn(struct pci_bus *bus, struct pci_dev *dev, unsigned fn)
1448 if (pci_ari_enabled(bus)) {
1451 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1455 pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap);
1456 next_fn = PCI_ARI_CAP_NFN(cap);
1458 return 0; /* protect against malformed list */
1463 /* dev may be NULL for non-contiguous multifunction devices */
1464 if (!dev || dev->multifunction)
1465 return (fn + 1) % 8;
1470 static int only_one_child(struct pci_bus *bus)
1472 struct pci_dev *parent = bus->self;
1474 if (!parent || !pci_is_pcie(parent))
1476 if (pci_pcie_type(parent) == PCI_EXP_TYPE_ROOT_PORT)
1478 if (pci_pcie_type(parent) == PCI_EXP_TYPE_DOWNSTREAM &&
1479 !pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
1485 * pci_scan_slot - scan a PCI slot on a bus for devices.
1486 * @bus: PCI bus to scan
1487 * @devfn: slot number to scan (must have zero function.)
1489 * Scan a PCI slot on the specified PCI bus for devices, adding
1490 * discovered devices to the @bus->devices list. New devices
1491 * will not have is_added set.
1493 * Returns the number of new devices found.
1495 int pci_scan_slot(struct pci_bus *bus, int devfn)
1497 unsigned fn, nr = 0;
1498 struct pci_dev *dev;
1500 if (only_one_child(bus) && (devfn > 0))
1501 return 0; /* Already scanned the entire slot */
1503 dev = pci_scan_single_device(bus, devfn);
1509 for (fn = next_fn(bus, dev, 0); fn > 0; fn = next_fn(bus, dev, fn)) {
1510 dev = pci_scan_single_device(bus, devfn + fn);
1514 dev->multifunction = 1;
1518 /* only one slot has pcie device */
1519 if (bus->self && nr)
1520 pcie_aspm_init_link_state(bus->self);
1524 EXPORT_SYMBOL(pci_scan_slot);
1526 static int pcie_find_smpss(struct pci_dev *dev, void *data)
1530 if (!pci_is_pcie(dev))
1534 * We don't have a way to change MPS settings on devices that have
1535 * drivers attached. A hot-added device might support only the minimum
1536 * MPS setting (MPS=128). Therefore, if the fabric contains a bridge
1537 * where devices may be hot-added, we limit the fabric MPS to 128 so
1538 * hot-added devices will work correctly.
1540 * However, if we hot-add a device to a slot directly below a Root
1541 * Port, it's impossible for there to be other existing devices below
1542 * the port. We don't limit the MPS in this case because we can
1543 * reconfigure MPS on both the Root Port and the hot-added device,
1544 * and there are no other devices involved.
1546 * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
1548 if (dev->is_hotplug_bridge &&
1549 pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
1552 if (*smpss > dev->pcie_mpss)
1553 *smpss = dev->pcie_mpss;
1558 static void pcie_write_mps(struct pci_dev *dev, int mps)
1562 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
1563 mps = 128 << dev->pcie_mpss;
1565 if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
1567 /* For "Performance", the assumption is made that
1568 * downstream communication will never be larger than
1569 * the MRRS. So, the MPS only needs to be configured
1570 * for the upstream communication. This being the case,
1571 * walk from the top down and set the MPS of the child
1572 * to that of the parent bus.
1574 * Configure the device MPS with the smaller of the
1575 * device MPSS or the bridge MPS (which is assumed to be
1576 * properly configured at this point to the largest
1577 * allowable MPS based on its parent bus).
1579 mps = min(mps, pcie_get_mps(dev->bus->self));
1582 rc = pcie_set_mps(dev, mps);
1584 dev_err(&dev->dev, "Failed attempting to set the MPS\n");
1587 static void pcie_write_mrrs(struct pci_dev *dev)
1591 /* In the "safe" case, do not configure the MRRS. There appear to be
1592 * issues with setting MRRS to 0 on a number of devices.
1594 if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
1597 /* For Max performance, the MRRS must be set to the largest supported
1598 * value. However, it cannot be configured larger than the MPS the
1599 * device or the bus can support. This should already be properly
1600 * configured by a prior call to pcie_write_mps.
1602 mrrs = pcie_get_mps(dev);
1604 /* MRRS is a R/W register. Invalid values can be written, but a
1605 * subsequent read will verify if the value is acceptable or not.
1606 * If the MRRS value provided is not acceptable (e.g., too large),
1607 * shrink the value until it is acceptable to the HW.
1609 while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
1610 rc = pcie_set_readrq(dev, mrrs);
1614 dev_warn(&dev->dev, "Failed attempting to set the MRRS\n");
1619 dev_err(&dev->dev, "MRRS was unable to be configured with a "
1620 "safe value. If problems are experienced, try running "
1621 "with pci=pcie_bus_safe.\n");
1624 static void pcie_bus_detect_mps(struct pci_dev *dev)
1626 struct pci_dev *bridge = dev->bus->self;
1632 mps = pcie_get_mps(dev);
1633 p_mps = pcie_get_mps(bridge);
1636 dev_warn(&dev->dev, "Max Payload Size %d, but upstream %s set to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
1637 mps, pci_name(bridge), p_mps);
1640 static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
1644 if (!pci_is_pcie(dev))
1647 if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
1648 pcie_bus_detect_mps(dev);
1652 mps = 128 << *(u8 *)data;
1653 orig_mps = pcie_get_mps(dev);
1655 pcie_write_mps(dev, mps);
1656 pcie_write_mrrs(dev);
1658 dev_info(&dev->dev, "Max Payload Size set to %4d/%4d (was %4d), "
1659 "Max Read Rq %4d\n", pcie_get_mps(dev), 128 << dev->pcie_mpss,
1660 orig_mps, pcie_get_readrq(dev));
1665 /* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down,
1666 * parents then children fashion. If this changes, then this code will not
1669 void pcie_bus_configure_settings(struct pci_bus *bus)
1676 if (!pci_is_pcie(bus->self))
1679 /* FIXME - Peer to peer DMA is possible, though the endpoint would need
1680 * to be aware of the MPS of the destination. To work around this,
1681 * simply force the MPS of the entire system to the smallest possible.
1683 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
1686 if (pcie_bus_config == PCIE_BUS_SAFE) {
1687 smpss = bus->self->pcie_mpss;
1689 pcie_find_smpss(bus->self, &smpss);
1690 pci_walk_bus(bus, pcie_find_smpss, &smpss);
1693 pcie_bus_configure_set(bus->self, &smpss);
1694 pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
1696 EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
1698 unsigned int pci_scan_child_bus(struct pci_bus *bus)
1700 unsigned int devfn, pass, max = bus->busn_res.start;
1701 struct pci_dev *dev;
1703 dev_dbg(&bus->dev, "scanning bus\n");
1705 /* Go find them, Rover! */
1706 for (devfn = 0; devfn < 0x100; devfn += 8)
1707 pci_scan_slot(bus, devfn);
1709 /* Reserve buses for SR-IOV capability. */
1710 max += pci_iov_bus_range(bus);
1713 * After performing arch-dependent fixup of the bus, look behind
1714 * all PCI-to-PCI bridges on this bus.
1716 if (!bus->is_added) {
1717 dev_dbg(&bus->dev, "fixups for bus\n");
1718 pcibios_fixup_bus(bus);
1722 for (pass=0; pass < 2; pass++)
1723 list_for_each_entry(dev, &bus->devices, bus_list) {
1724 if (pci_is_bridge(dev))
1725 max = pci_scan_bridge(bus, dev, max, pass);
1729 * We've scanned the bus and so we know all about what's on
1730 * the other side of any bridges that may be on this bus plus
1733 * Return how far we've got finding sub-buses.
1735 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
1738 EXPORT_SYMBOL_GPL(pci_scan_child_bus);
1741 * pcibios_root_bridge_prepare - Platform-specific host bridge setup.
1742 * @bridge: Host bridge to set up.
1744 * Default empty implementation. Replace with an architecture-specific setup
1745 * routine, if necessary.
1747 int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
1752 void __weak pcibios_add_bus(struct pci_bus *bus)
1756 void __weak pcibios_remove_bus(struct pci_bus *bus)
1760 struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
1761 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1764 struct pci_host_bridge *bridge;
1765 struct pci_bus *b, *b2;
1766 struct pci_host_bridge_window *window, *n;
1767 struct resource *res;
1768 resource_size_t offset;
1772 b = pci_alloc_bus();
1776 b->sysdata = sysdata;
1778 b->number = b->busn_res.start = bus;
1779 b2 = pci_find_bus(pci_domain_nr(b), bus);
1781 /* If we already got to this bus through a different bridge, ignore it */
1782 dev_dbg(&b2->dev, "bus already known\n");
1786 bridge = pci_alloc_host_bridge(b);
1790 bridge->dev.parent = parent;
1791 bridge->dev.release = pci_release_host_bridge_dev;
1792 dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
1793 error = pcibios_root_bridge_prepare(bridge);
1799 error = device_register(&bridge->dev);
1801 put_device(&bridge->dev);
1804 b->bridge = get_device(&bridge->dev);
1805 device_enable_async_suspend(b->bridge);
1806 pci_set_bus_of_node(b);
1809 set_dev_node(b->bridge, pcibus_to_node(b));
1811 b->dev.class = &pcibus_class;
1812 b->dev.parent = b->bridge;
1813 dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
1814 error = device_register(&b->dev);
1816 goto class_dev_reg_err;
1820 /* Create legacy_io and legacy_mem files for this bus */
1821 pci_create_legacy_files(b);
1824 dev_info(parent, "PCI host bridge to bus %s\n", dev_name(&b->dev));
1826 printk(KERN_INFO "PCI host bridge to bus %s\n", dev_name(&b->dev));
1828 /* Add initial resources to the bus */
1829 list_for_each_entry_safe(window, n, resources, list) {
1830 list_move_tail(&window->list, &bridge->windows);
1832 offset = window->offset;
1833 if (res->flags & IORESOURCE_BUS)
1834 pci_bus_insert_busn_res(b, bus, res->end);
1836 pci_bus_add_resource(b, res, 0);
1838 if (resource_type(res) == IORESOURCE_IO)
1839 fmt = " (bus address [%#06llx-%#06llx])";
1841 fmt = " (bus address [%#010llx-%#010llx])";
1842 snprintf(bus_addr, sizeof(bus_addr), fmt,
1843 (unsigned long long) (res->start - offset),
1844 (unsigned long long) (res->end - offset));
1847 dev_info(&b->dev, "root bus resource %pR%s\n", res, bus_addr);
1850 down_write(&pci_bus_sem);
1851 list_add_tail(&b->node, &pci_root_buses);
1852 up_write(&pci_bus_sem);
1857 put_device(&bridge->dev);
1858 device_unregister(&bridge->dev);
1864 int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
1866 struct resource *res = &b->busn_res;
1867 struct resource *parent_res, *conflict;
1871 res->flags = IORESOURCE_BUS;
1873 if (!pci_is_root_bus(b))
1874 parent_res = &b->parent->busn_res;
1876 parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
1877 res->flags |= IORESOURCE_PCI_FIXED;
1880 conflict = request_resource_conflict(parent_res, res);
1883 dev_printk(KERN_DEBUG, &b->dev,
1884 "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
1885 res, pci_is_root_bus(b) ? "domain " : "",
1886 parent_res, conflict->name, conflict);
1888 return conflict == NULL;
1891 int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
1893 struct resource *res = &b->busn_res;
1894 struct resource old_res = *res;
1895 resource_size_t size;
1898 if (res->start > bus_max)
1901 size = bus_max - res->start + 1;
1902 ret = adjust_resource(res, res->start, size);
1903 dev_printk(KERN_DEBUG, &b->dev,
1904 "busn_res: %pR end %s updated to %02x\n",
1905 &old_res, ret ? "can not be" : "is", bus_max);
1907 if (!ret && !res->parent)
1908 pci_bus_insert_busn_res(b, res->start, res->end);
1913 void pci_bus_release_busn_res(struct pci_bus *b)
1915 struct resource *res = &b->busn_res;
1918 if (!res->flags || !res->parent)
1921 ret = release_resource(res);
1922 dev_printk(KERN_DEBUG, &b->dev,
1923 "busn_res: %pR %s released\n",
1924 res, ret ? "can not be" : "is");
1927 struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
1928 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1930 struct pci_host_bridge_window *window;
1935 list_for_each_entry(window, resources, list)
1936 if (window->res->flags & IORESOURCE_BUS) {
1941 b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
1947 "No busn resource found for root bus, will use [bus %02x-ff]\n",
1949 pci_bus_insert_busn_res(b, bus, 255);
1952 max = pci_scan_child_bus(b);
1955 pci_bus_update_busn_res_end(b, max);
1957 pci_bus_add_devices(b);
1960 EXPORT_SYMBOL(pci_scan_root_bus);
1962 /* Deprecated; use pci_scan_root_bus() instead */
1963 struct pci_bus *pci_scan_bus_parented(struct device *parent,
1964 int bus, struct pci_ops *ops, void *sysdata)
1966 LIST_HEAD(resources);
1969 pci_add_resource(&resources, &ioport_resource);
1970 pci_add_resource(&resources, &iomem_resource);
1971 pci_add_resource(&resources, &busn_resource);
1972 b = pci_create_root_bus(parent, bus, ops, sysdata, &resources);
1974 pci_scan_child_bus(b);
1976 pci_free_resource_list(&resources);
1979 EXPORT_SYMBOL(pci_scan_bus_parented);
1981 struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
1984 LIST_HEAD(resources);
1987 pci_add_resource(&resources, &ioport_resource);
1988 pci_add_resource(&resources, &iomem_resource);
1989 pci_add_resource(&resources, &busn_resource);
1990 b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
1992 pci_scan_child_bus(b);
1993 pci_bus_add_devices(b);
1995 pci_free_resource_list(&resources);
1999 EXPORT_SYMBOL(pci_scan_bus);
2002 * pci_rescan_bus_bridge_resize - scan a PCI bus for devices.
2003 * @bridge: PCI bridge for the bus to scan
2005 * Scan a PCI bus and child buses for new devices, add them,
2006 * and enable them, resizing bridge mmio/io resource if necessary
2007 * and possible. The caller must ensure the child devices are already
2008 * removed for resizing to occur.
2010 * Returns the max number of subordinate bus discovered.
2012 unsigned int pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
2015 struct pci_bus *bus = bridge->subordinate;
2017 max = pci_scan_child_bus(bus);
2019 pci_assign_unassigned_bridge_resources(bridge);
2021 pci_bus_add_devices(bus);
2027 * pci_rescan_bus - scan a PCI bus for devices.
2028 * @bus: PCI bus to scan
2030 * Scan a PCI bus and child buses for new devices, adds them,
2033 * Returns the max number of subordinate bus discovered.
2035 unsigned int pci_rescan_bus(struct pci_bus *bus)
2039 max = pci_scan_child_bus(bus);
2040 pci_assign_unassigned_bus_resources(bus);
2041 pci_bus_add_devices(bus);
2045 EXPORT_SYMBOL_GPL(pci_rescan_bus);
2048 * pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal
2049 * routines should always be executed under this mutex.
2051 static DEFINE_MUTEX(pci_rescan_remove_lock);
2053 void pci_lock_rescan_remove(void)
2055 mutex_lock(&pci_rescan_remove_lock);
2057 EXPORT_SYMBOL_GPL(pci_lock_rescan_remove);
2059 void pci_unlock_rescan_remove(void)
2061 mutex_unlock(&pci_rescan_remove_lock);
2063 EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove);
2065 static int __init pci_sort_bf_cmp(const struct device *d_a, const struct device *d_b)
2067 const struct pci_dev *a = to_pci_dev(d_a);
2068 const struct pci_dev *b = to_pci_dev(d_b);
2070 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
2071 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
2073 if (a->bus->number < b->bus->number) return -1;
2074 else if (a->bus->number > b->bus->number) return 1;
2076 if (a->devfn < b->devfn) return -1;
2077 else if (a->devfn > b->devfn) return 1;
2082 void __init pci_sort_breadthfirst(void)
2084 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);