ASoC: twl4030: Convert to use devm_kzalloc
[linux-2.6/btrfs-unstable.git] / drivers / pci / probe.c
blob6c143b4497ca4381677dcc34459ecf269e5cdc88
1 /*
2 * probe.c - PCI detection and setup code
3 */
5 #include <linux/kernel.h>
6 #include <linux/delay.h>
7 #include <linux/init.h>
8 #include <linux/pci.h>
9 #include <linux/slab.h>
10 #include <linux/module.h>
11 #include <linux/cpumask.h>
12 #include <linux/pci-aspm.h>
13 #include <asm-generic/pci-bridge.h>
14 #include "pci.h"
16 #define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
17 #define CARDBUS_RESERVE_BUSNR 3
19 struct resource busn_resource = {
20 .name = "PCI busn",
21 .start = 0,
22 .end = 255,
23 .flags = IORESOURCE_BUS,
26 /* Ugh. Need to stop exporting this to modules. */
27 LIST_HEAD(pci_root_buses);
28 EXPORT_SYMBOL(pci_root_buses);
30 static LIST_HEAD(pci_domain_busn_res_list);
32 struct pci_domain_busn_res {
33 struct list_head list;
34 struct resource res;
35 int domain_nr;
38 static struct resource *get_pci_domain_busn_res(int domain_nr)
40 struct pci_domain_busn_res *r;
42 list_for_each_entry(r, &pci_domain_busn_res_list, list)
43 if (r->domain_nr == domain_nr)
44 return &r->res;
46 r = kzalloc(sizeof(*r), GFP_KERNEL);
47 if (!r)
48 return NULL;
50 r->domain_nr = domain_nr;
51 r->res.start = 0;
52 r->res.end = 0xff;
53 r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
55 list_add_tail(&r->list, &pci_domain_busn_res_list);
57 return &r->res;
60 static int find_anything(struct device *dev, void *data)
62 return 1;
66 * Some device drivers need know if pci is initiated.
67 * Basically, we think pci is not initiated when there
68 * is no device to be found on the pci_bus_type.
70 int no_pci_devices(void)
72 struct device *dev;
73 int no_devices;
75 dev = bus_find_device(&pci_bus_type, NULL, NULL, find_anything);
76 no_devices = (dev == NULL);
77 put_device(dev);
78 return no_devices;
80 EXPORT_SYMBOL(no_pci_devices);
83 * PCI Bus Class
85 static void release_pcibus_dev(struct device *dev)
87 struct pci_bus *pci_bus = to_pci_bus(dev);
89 if (pci_bus->bridge)
90 put_device(pci_bus->bridge);
91 pci_bus_remove_resources(pci_bus);
92 pci_release_bus_of_node(pci_bus);
93 kfree(pci_bus);
96 static struct class pcibus_class = {
97 .name = "pci_bus",
98 .dev_release = &release_pcibus_dev,
99 .dev_attrs = pcibus_dev_attrs,
102 static int __init pcibus_class_init(void)
104 return class_register(&pcibus_class);
106 postcore_initcall(pcibus_class_init);
108 static u64 pci_size(u64 base, u64 maxbase, u64 mask)
110 u64 size = mask & maxbase; /* Find the significant bits */
111 if (!size)
112 return 0;
114 /* Get the lowest of them to find the decode size, and
115 from that the extent. */
116 size = (size & ~(size-1)) - 1;
118 /* base == maxbase can be valid only if the BAR has
119 already been programmed with all 1s. */
120 if (base == maxbase && ((base | size) & mask) != mask)
121 return 0;
123 return size;
126 static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
128 u32 mem_type;
129 unsigned long flags;
131 if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
132 flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
133 flags |= IORESOURCE_IO;
134 return flags;
137 flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
138 flags |= IORESOURCE_MEM;
139 if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
140 flags |= IORESOURCE_PREFETCH;
142 mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
143 switch (mem_type) {
144 case PCI_BASE_ADDRESS_MEM_TYPE_32:
145 break;
146 case PCI_BASE_ADDRESS_MEM_TYPE_1M:
147 dev_info(&dev->dev, "1M mem BAR treated as 32-bit BAR\n");
148 break;
149 case PCI_BASE_ADDRESS_MEM_TYPE_64:
150 flags |= IORESOURCE_MEM_64;
151 break;
152 default:
153 dev_warn(&dev->dev,
154 "mem unknown type %x treated as 32-bit BAR\n",
155 mem_type);
156 break;
158 return flags;
162 * pci_read_base - read a PCI BAR
163 * @dev: the PCI device
164 * @type: type of the BAR
165 * @res: resource buffer to be filled in
166 * @pos: BAR position in the config space
168 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
170 int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
171 struct resource *res, unsigned int pos)
173 u32 l, sz, mask;
174 u16 orig_cmd;
175 struct pci_bus_region region;
177 mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
179 if (!dev->mmio_always_on) {
180 pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
181 pci_write_config_word(dev, PCI_COMMAND,
182 orig_cmd & ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO));
185 res->name = pci_name(dev);
187 pci_read_config_dword(dev, pos, &l);
188 pci_write_config_dword(dev, pos, l | mask);
189 pci_read_config_dword(dev, pos, &sz);
190 pci_write_config_dword(dev, pos, l);
193 * All bits set in sz means the device isn't working properly.
194 * If the BAR isn't implemented, all bits must be 0. If it's a
195 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
196 * 1 must be clear.
198 if (!sz || sz == 0xffffffff)
199 goto fail;
202 * I don't know how l can have all bits set. Copied from old code.
203 * Maybe it fixes a bug on some ancient platform.
205 if (l == 0xffffffff)
206 l = 0;
208 if (type == pci_bar_unknown) {
209 res->flags = decode_bar(dev, l);
210 res->flags |= IORESOURCE_SIZEALIGN;
211 if (res->flags & IORESOURCE_IO) {
212 l &= PCI_BASE_ADDRESS_IO_MASK;
213 mask = PCI_BASE_ADDRESS_IO_MASK & (u32) IO_SPACE_LIMIT;
214 } else {
215 l &= PCI_BASE_ADDRESS_MEM_MASK;
216 mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
218 } else {
219 res->flags |= (l & IORESOURCE_ROM_ENABLE);
220 l &= PCI_ROM_ADDRESS_MASK;
221 mask = (u32)PCI_ROM_ADDRESS_MASK;
224 if (res->flags & IORESOURCE_MEM_64) {
225 u64 l64 = l;
226 u64 sz64 = sz;
227 u64 mask64 = mask | (u64)~0 << 32;
229 pci_read_config_dword(dev, pos + 4, &l);
230 pci_write_config_dword(dev, pos + 4, ~0);
231 pci_read_config_dword(dev, pos + 4, &sz);
232 pci_write_config_dword(dev, pos + 4, l);
234 l64 |= ((u64)l << 32);
235 sz64 |= ((u64)sz << 32);
237 sz64 = pci_size(l64, sz64, mask64);
239 if (!sz64)
240 goto fail;
242 if ((sizeof(resource_size_t) < 8) && (sz64 > 0x100000000ULL)) {
243 dev_err(&dev->dev, "reg %x: can't handle 64-bit BAR\n",
244 pos);
245 goto fail;
248 if ((sizeof(resource_size_t) < 8) && l) {
249 /* Address above 32-bit boundary; disable the BAR */
250 pci_write_config_dword(dev, pos, 0);
251 pci_write_config_dword(dev, pos + 4, 0);
252 region.start = 0;
253 region.end = sz64;
254 pcibios_bus_to_resource(dev, res, &region);
255 } else {
256 region.start = l64;
257 region.end = l64 + sz64;
258 pcibios_bus_to_resource(dev, res, &region);
259 dev_printk(KERN_DEBUG, &dev->dev, "reg %x: %pR\n",
260 pos, res);
262 } else {
263 sz = pci_size(l, sz, mask);
265 if (!sz)
266 goto fail;
268 region.start = l;
269 region.end = l + sz;
270 pcibios_bus_to_resource(dev, res, &region);
272 dev_printk(KERN_DEBUG, &dev->dev, "reg %x: %pR\n", pos, res);
275 out:
276 if (!dev->mmio_always_on)
277 pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
279 return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
280 fail:
281 res->flags = 0;
282 goto out;
285 static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
287 unsigned int pos, reg;
289 for (pos = 0; pos < howmany; pos++) {
290 struct resource *res = &dev->resource[pos];
291 reg = PCI_BASE_ADDRESS_0 + (pos << 2);
292 pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
295 if (rom) {
296 struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
297 dev->rom_base_reg = rom;
298 res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
299 IORESOURCE_READONLY | IORESOURCE_CACHEABLE |
300 IORESOURCE_SIZEALIGN;
301 __pci_read_base(dev, pci_bar_mem32, res, rom);
305 static void __devinit pci_read_bridge_io(struct pci_bus *child)
307 struct pci_dev *dev = child->self;
308 u8 io_base_lo, io_limit_lo;
309 unsigned long io_mask, io_granularity, base, limit;
310 struct pci_bus_region region;
311 struct resource *res;
313 io_mask = PCI_IO_RANGE_MASK;
314 io_granularity = 0x1000;
315 if (dev->io_window_1k) {
316 /* Support 1K I/O space granularity */
317 io_mask = PCI_IO_1K_RANGE_MASK;
318 io_granularity = 0x400;
321 res = child->resource[0];
322 pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
323 pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
324 base = (io_base_lo & io_mask) << 8;
325 limit = (io_limit_lo & io_mask) << 8;
327 if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
328 u16 io_base_hi, io_limit_hi;
330 pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
331 pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
332 base |= ((unsigned long) io_base_hi << 16);
333 limit |= ((unsigned long) io_limit_hi << 16);
336 if (base <= limit) {
337 res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
338 region.start = base;
339 region.end = limit + io_granularity - 1;
340 pcibios_bus_to_resource(dev, res, &region);
341 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
345 static void __devinit pci_read_bridge_mmio(struct pci_bus *child)
347 struct pci_dev *dev = child->self;
348 u16 mem_base_lo, mem_limit_lo;
349 unsigned long base, limit;
350 struct pci_bus_region region;
351 struct resource *res;
353 res = child->resource[1];
354 pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
355 pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
356 base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
357 limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
358 if (base <= limit) {
359 res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
360 region.start = base;
361 region.end = limit + 0xfffff;
362 pcibios_bus_to_resource(dev, res, &region);
363 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
367 static void __devinit pci_read_bridge_mmio_pref(struct pci_bus *child)
369 struct pci_dev *dev = child->self;
370 u16 mem_base_lo, mem_limit_lo;
371 unsigned long base, limit;
372 struct pci_bus_region region;
373 struct resource *res;
375 res = child->resource[2];
376 pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
377 pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
378 base = ((unsigned long) mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
379 limit = ((unsigned long) mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
381 if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
382 u32 mem_base_hi, mem_limit_hi;
384 pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
385 pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
388 * Some bridges set the base > limit by default, and some
389 * (broken) BIOSes do not initialize them. If we find
390 * this, just assume they are not being used.
392 if (mem_base_hi <= mem_limit_hi) {
393 #if BITS_PER_LONG == 64
394 base |= ((unsigned long) mem_base_hi) << 32;
395 limit |= ((unsigned long) mem_limit_hi) << 32;
396 #else
397 if (mem_base_hi || mem_limit_hi) {
398 dev_err(&dev->dev, "can't handle 64-bit "
399 "address space for bridge\n");
400 return;
402 #endif
405 if (base <= limit) {
406 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
407 IORESOURCE_MEM | IORESOURCE_PREFETCH;
408 if (res->flags & PCI_PREF_RANGE_TYPE_64)
409 res->flags |= IORESOURCE_MEM_64;
410 region.start = base;
411 region.end = limit + 0xfffff;
412 pcibios_bus_to_resource(dev, res, &region);
413 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
417 void __devinit pci_read_bridge_bases(struct pci_bus *child)
419 struct pci_dev *dev = child->self;
420 struct resource *res;
421 int i;
423 if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
424 return;
426 dev_info(&dev->dev, "PCI bridge to %pR%s\n",
427 &child->busn_res,
428 dev->transparent ? " (subtractive decode)" : "");
430 pci_bus_remove_resources(child);
431 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
432 child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
434 pci_read_bridge_io(child);
435 pci_read_bridge_mmio(child);
436 pci_read_bridge_mmio_pref(child);
438 if (dev->transparent) {
439 pci_bus_for_each_resource(child->parent, res, i) {
440 if (res) {
441 pci_bus_add_resource(child, res,
442 PCI_SUBTRACTIVE_DECODE);
443 dev_printk(KERN_DEBUG, &dev->dev,
444 " bridge window %pR (subtractive decode)\n",
445 res);
451 static struct pci_bus * pci_alloc_bus(void)
453 struct pci_bus *b;
455 b = kzalloc(sizeof(*b), GFP_KERNEL);
456 if (b) {
457 INIT_LIST_HEAD(&b->node);
458 INIT_LIST_HEAD(&b->children);
459 INIT_LIST_HEAD(&b->devices);
460 INIT_LIST_HEAD(&b->slots);
461 INIT_LIST_HEAD(&b->resources);
462 b->max_bus_speed = PCI_SPEED_UNKNOWN;
463 b->cur_bus_speed = PCI_SPEED_UNKNOWN;
465 return b;
468 static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b)
470 struct pci_host_bridge *bridge;
472 bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
473 if (bridge) {
474 INIT_LIST_HEAD(&bridge->windows);
475 bridge->bus = b;
478 return bridge;
481 static unsigned char pcix_bus_speed[] = {
482 PCI_SPEED_UNKNOWN, /* 0 */
483 PCI_SPEED_66MHz_PCIX, /* 1 */
484 PCI_SPEED_100MHz_PCIX, /* 2 */
485 PCI_SPEED_133MHz_PCIX, /* 3 */
486 PCI_SPEED_UNKNOWN, /* 4 */
487 PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
488 PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
489 PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
490 PCI_SPEED_UNKNOWN, /* 8 */
491 PCI_SPEED_66MHz_PCIX_266, /* 9 */
492 PCI_SPEED_100MHz_PCIX_266, /* A */
493 PCI_SPEED_133MHz_PCIX_266, /* B */
494 PCI_SPEED_UNKNOWN, /* C */
495 PCI_SPEED_66MHz_PCIX_533, /* D */
496 PCI_SPEED_100MHz_PCIX_533, /* E */
497 PCI_SPEED_133MHz_PCIX_533 /* F */
500 static unsigned char pcie_link_speed[] = {
501 PCI_SPEED_UNKNOWN, /* 0 */
502 PCIE_SPEED_2_5GT, /* 1 */
503 PCIE_SPEED_5_0GT, /* 2 */
504 PCIE_SPEED_8_0GT, /* 3 */
505 PCI_SPEED_UNKNOWN, /* 4 */
506 PCI_SPEED_UNKNOWN, /* 5 */
507 PCI_SPEED_UNKNOWN, /* 6 */
508 PCI_SPEED_UNKNOWN, /* 7 */
509 PCI_SPEED_UNKNOWN, /* 8 */
510 PCI_SPEED_UNKNOWN, /* 9 */
511 PCI_SPEED_UNKNOWN, /* A */
512 PCI_SPEED_UNKNOWN, /* B */
513 PCI_SPEED_UNKNOWN, /* C */
514 PCI_SPEED_UNKNOWN, /* D */
515 PCI_SPEED_UNKNOWN, /* E */
516 PCI_SPEED_UNKNOWN /* F */
519 void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
521 bus->cur_bus_speed = pcie_link_speed[linksta & 0xf];
523 EXPORT_SYMBOL_GPL(pcie_update_link_speed);
525 static unsigned char agp_speeds[] = {
526 AGP_UNKNOWN,
527 AGP_1X,
528 AGP_2X,
529 AGP_4X,
530 AGP_8X
533 static enum pci_bus_speed agp_speed(int agp3, int agpstat)
535 int index = 0;
537 if (agpstat & 4)
538 index = 3;
539 else if (agpstat & 2)
540 index = 2;
541 else if (agpstat & 1)
542 index = 1;
543 else
544 goto out;
546 if (agp3) {
547 index += 2;
548 if (index == 5)
549 index = 0;
552 out:
553 return agp_speeds[index];
557 static void pci_set_bus_speed(struct pci_bus *bus)
559 struct pci_dev *bridge = bus->self;
560 int pos;
562 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
563 if (!pos)
564 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
565 if (pos) {
566 u32 agpstat, agpcmd;
568 pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
569 bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
571 pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
572 bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
575 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
576 if (pos) {
577 u16 status;
578 enum pci_bus_speed max;
579 pci_read_config_word(bridge, pos + 2, &status);
581 if (status & 0x8000) {
582 max = PCI_SPEED_133MHz_PCIX_533;
583 } else if (status & 0x4000) {
584 max = PCI_SPEED_133MHz_PCIX_266;
585 } else if (status & 0x0002) {
586 if (((status >> 12) & 0x3) == 2) {
587 max = PCI_SPEED_133MHz_PCIX_ECC;
588 } else {
589 max = PCI_SPEED_133MHz_PCIX;
591 } else {
592 max = PCI_SPEED_66MHz_PCIX;
595 bus->max_bus_speed = max;
596 bus->cur_bus_speed = pcix_bus_speed[(status >> 6) & 0xf];
598 return;
601 pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
602 if (pos) {
603 u32 linkcap;
604 u16 linksta;
606 pci_read_config_dword(bridge, pos + PCI_EXP_LNKCAP, &linkcap);
607 bus->max_bus_speed = pcie_link_speed[linkcap & 0xf];
609 pci_read_config_word(bridge, pos + PCI_EXP_LNKSTA, &linksta);
610 pcie_update_link_speed(bus, linksta);
615 static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
616 struct pci_dev *bridge, int busnr)
618 struct pci_bus *child;
619 int i;
622 * Allocate a new bus, and inherit stuff from the parent..
624 child = pci_alloc_bus();
625 if (!child)
626 return NULL;
628 child->parent = parent;
629 child->ops = parent->ops;
630 child->sysdata = parent->sysdata;
631 child->bus_flags = parent->bus_flags;
633 /* initialize some portions of the bus device, but don't register it
634 * now as the parent is not properly set up yet. This device will get
635 * registered later in pci_bus_add_devices()
637 child->dev.class = &pcibus_class;
638 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
641 * Set up the primary, secondary and subordinate
642 * bus numbers.
644 child->number = child->busn_res.start = busnr;
645 child->primary = parent->busn_res.start;
646 child->busn_res.end = 0xff;
648 if (!bridge)
649 return child;
651 child->self = bridge;
652 child->bridge = get_device(&bridge->dev);
653 pci_set_bus_of_node(child);
654 pci_set_bus_speed(child);
656 /* Set up default resource pointers and names.. */
657 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
658 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
659 child->resource[i]->name = child->name;
661 bridge->subordinate = child;
663 return child;
666 struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr)
668 struct pci_bus *child;
670 child = pci_alloc_child_bus(parent, dev, busnr);
671 if (child) {
672 down_write(&pci_bus_sem);
673 list_add_tail(&child->node, &parent->children);
674 up_write(&pci_bus_sem);
676 return child;
679 static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
681 struct pci_bus *parent = child->parent;
683 /* Attempts to fix that up are really dangerous unless
684 we're going to re-assign all bus numbers. */
685 if (!pcibios_assign_all_busses())
686 return;
688 while (parent->parent && parent->busn_res.end < max) {
689 parent->busn_res.end = max;
690 pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);
691 parent = parent->parent;
696 * If it's a bridge, configure it and scan the bus behind it.
697 * For CardBus bridges, we don't scan behind as the devices will
698 * be handled by the bridge driver itself.
700 * We need to process bridges in two passes -- first we scan those
701 * already configured by the BIOS and after we are done with all of
702 * them, we proceed to assigning numbers to the remaining buses in
703 * order to avoid overlaps between old and new bus numbers.
705 int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
707 struct pci_bus *child;
708 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
709 u32 buses, i, j = 0;
710 u16 bctl;
711 u8 primary, secondary, subordinate;
712 int broken = 0;
714 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
715 primary = buses & 0xFF;
716 secondary = (buses >> 8) & 0xFF;
717 subordinate = (buses >> 16) & 0xFF;
719 dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
720 secondary, subordinate, pass);
722 if (!primary && (primary != bus->number) && secondary && subordinate) {
723 dev_warn(&dev->dev, "Primary bus is hard wired to 0\n");
724 primary = bus->number;
727 /* Check if setup is sensible at all */
728 if (!pass &&
729 (primary != bus->number || secondary <= bus->number)) {
730 dev_dbg(&dev->dev, "bus configuration invalid, reconfiguring\n");
731 broken = 1;
734 /* Disable MasterAbortMode during probing to avoid reporting
735 of bus errors (in some architectures) */
736 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
737 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
738 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
740 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
741 !is_cardbus && !broken) {
742 unsigned int cmax;
744 * Bus already configured by firmware, process it in the first
745 * pass and just note the configuration.
747 if (pass)
748 goto out;
751 * If we already got to this bus through a different bridge,
752 * don't re-add it. This can happen with the i450NX chipset.
754 * However, we continue to descend down the hierarchy and
755 * scan remaining child buses.
757 child = pci_find_bus(pci_domain_nr(bus), secondary);
758 if (!child) {
759 child = pci_add_new_bus(bus, dev, secondary);
760 if (!child)
761 goto out;
762 child->primary = primary;
763 pci_bus_insert_busn_res(child, secondary, subordinate);
764 child->bridge_ctl = bctl;
767 cmax = pci_scan_child_bus(child);
768 if (cmax > max)
769 max = cmax;
770 if (child->busn_res.end > max)
771 max = child->busn_res.end;
772 } else {
774 * We need to assign a number to this bus which we always
775 * do in the second pass.
777 if (!pass) {
778 if (pcibios_assign_all_busses() || broken)
779 /* Temporarily disable forwarding of the
780 configuration cycles on all bridges in
781 this bus segment to avoid possible
782 conflicts in the second pass between two
783 bridges programmed with overlapping
784 bus ranges. */
785 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
786 buses & ~0xffffff);
787 goto out;
790 /* Clear errors */
791 pci_write_config_word(dev, PCI_STATUS, 0xffff);
793 /* Prevent assigning a bus number that already exists.
794 * This can happen when a bridge is hot-plugged, so in
795 * this case we only re-scan this bus. */
796 child = pci_find_bus(pci_domain_nr(bus), max+1);
797 if (!child) {
798 child = pci_add_new_bus(bus, dev, ++max);
799 if (!child)
800 goto out;
801 pci_bus_insert_busn_res(child, max, 0xff);
803 buses = (buses & 0xff000000)
804 | ((unsigned int)(child->primary) << 0)
805 | ((unsigned int)(child->busn_res.start) << 8)
806 | ((unsigned int)(child->busn_res.end) << 16);
809 * yenta.c forces a secondary latency timer of 176.
810 * Copy that behaviour here.
812 if (is_cardbus) {
813 buses &= ~0xff000000;
814 buses |= CARDBUS_LATENCY_TIMER << 24;
818 * We need to blast all three values with a single write.
820 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
822 if (!is_cardbus) {
823 child->bridge_ctl = bctl;
825 * Adjust subordinate busnr in parent buses.
826 * We do this before scanning for children because
827 * some devices may not be detected if the bios
828 * was lazy.
830 pci_fixup_parent_subordinate_busnr(child, max);
831 /* Now we can scan all subordinate buses... */
832 max = pci_scan_child_bus(child);
834 * now fix it up again since we have found
835 * the real value of max.
837 pci_fixup_parent_subordinate_busnr(child, max);
838 } else {
840 * For CardBus bridges, we leave 4 bus numbers
841 * as cards with a PCI-to-PCI bridge can be
842 * inserted later.
844 for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
845 struct pci_bus *parent = bus;
846 if (pci_find_bus(pci_domain_nr(bus),
847 max+i+1))
848 break;
849 while (parent->parent) {
850 if ((!pcibios_assign_all_busses()) &&
851 (parent->busn_res.end > max) &&
852 (parent->busn_res.end <= max+i)) {
853 j = 1;
855 parent = parent->parent;
857 if (j) {
859 * Often, there are two cardbus bridges
860 * -- try to leave one valid bus number
861 * for each one.
863 i /= 2;
864 break;
867 max += i;
868 pci_fixup_parent_subordinate_busnr(child, max);
871 * Set the subordinate bus number to its real value.
873 pci_bus_update_busn_res_end(child, max);
874 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
877 sprintf(child->name,
878 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
879 pci_domain_nr(bus), child->number);
881 /* Has only triggered on CardBus, fixup is in yenta_socket */
882 while (bus->parent) {
883 if ((child->busn_res.end > bus->busn_res.end) ||
884 (child->number > bus->busn_res.end) ||
885 (child->number < bus->number) ||
886 (child->busn_res.end < bus->number)) {
887 dev_info(&child->dev, "%pR %s "
888 "hidden behind%s bridge %s %pR\n",
889 &child->busn_res,
890 (bus->number > child->busn_res.end &&
891 bus->busn_res.end < child->number) ?
892 "wholly" : "partially",
893 bus->self->transparent ? " transparent" : "",
894 dev_name(&bus->dev),
895 &bus->busn_res);
897 bus = bus->parent;
900 out:
901 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
903 return max;
907 * Read interrupt line and base address registers.
908 * The architecture-dependent code can tweak these, of course.
910 static void pci_read_irq(struct pci_dev *dev)
912 unsigned char irq;
914 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
915 dev->pin = irq;
916 if (irq)
917 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
918 dev->irq = irq;
921 void set_pcie_port_type(struct pci_dev *pdev)
923 int pos;
924 u16 reg16;
926 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
927 if (!pos)
928 return;
929 pdev->is_pcie = 1;
930 pdev->pcie_cap = pos;
931 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, &reg16);
932 pdev->pcie_type = (reg16 & PCI_EXP_FLAGS_TYPE) >> 4;
933 pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, &reg16);
934 pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
937 void set_pcie_hotplug_bridge(struct pci_dev *pdev)
939 int pos;
940 u16 reg16;
941 u32 reg32;
943 pos = pci_pcie_cap(pdev);
944 if (!pos)
945 return;
946 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, &reg16);
947 if (!(reg16 & PCI_EXP_FLAGS_SLOT))
948 return;
949 pci_read_config_dword(pdev, pos + PCI_EXP_SLTCAP, &reg32);
950 if (reg32 & PCI_EXP_SLTCAP_HPC)
951 pdev->is_hotplug_bridge = 1;
954 #define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
957 * pci_setup_device - fill in class and map information of a device
958 * @dev: the device structure to fill
960 * Initialize the device structure with information about the device's
961 * vendor,class,memory and IO-space addresses,IRQ lines etc.
962 * Called at initialisation of the PCI subsystem and by CardBus services.
963 * Returns 0 on success and negative if unknown type of device (not normal,
964 * bridge or CardBus).
966 int pci_setup_device(struct pci_dev *dev)
968 u32 class;
969 u8 hdr_type;
970 struct pci_slot *slot;
971 int pos = 0;
972 struct pci_bus_region region;
973 struct resource *res;
975 if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
976 return -EIO;
978 dev->sysdata = dev->bus->sysdata;
979 dev->dev.parent = dev->bus->bridge;
980 dev->dev.bus = &pci_bus_type;
981 dev->hdr_type = hdr_type & 0x7f;
982 dev->multifunction = !!(hdr_type & 0x80);
983 dev->error_state = pci_channel_io_normal;
984 set_pcie_port_type(dev);
986 list_for_each_entry(slot, &dev->bus->slots, list)
987 if (PCI_SLOT(dev->devfn) == slot->number)
988 dev->slot = slot;
990 /* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
991 set this higher, assuming the system even supports it. */
992 dev->dma_mask = 0xffffffff;
994 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
995 dev->bus->number, PCI_SLOT(dev->devfn),
996 PCI_FUNC(dev->devfn));
998 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
999 dev->revision = class & 0xff;
1000 dev->class = class >> 8; /* upper 3 bytes */
1002 dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %02x class %#08x\n",
1003 dev->vendor, dev->device, dev->hdr_type, dev->class);
1005 /* need to have dev->class ready */
1006 dev->cfg_size = pci_cfg_space_size(dev);
1008 /* "Unknown power state" */
1009 dev->current_state = PCI_UNKNOWN;
1011 /* Early fixups, before probing the BARs */
1012 pci_fixup_device(pci_fixup_early, dev);
1013 /* device class may be changed after fixup */
1014 class = dev->class >> 8;
1016 switch (dev->hdr_type) { /* header type */
1017 case PCI_HEADER_TYPE_NORMAL: /* standard header */
1018 if (class == PCI_CLASS_BRIDGE_PCI)
1019 goto bad;
1020 pci_read_irq(dev);
1021 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1022 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1023 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
1026 * Do the ugly legacy mode stuff here rather than broken chip
1027 * quirk code. Legacy mode ATA controllers have fixed
1028 * addresses. These are not always echoed in BAR0-3, and
1029 * BAR0-3 in a few cases contain junk!
1031 if (class == PCI_CLASS_STORAGE_IDE) {
1032 u8 progif;
1033 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1034 if ((progif & 1) == 0) {
1035 region.start = 0x1F0;
1036 region.end = 0x1F7;
1037 res = &dev->resource[0];
1038 res->flags = LEGACY_IO_RESOURCE;
1039 pcibios_bus_to_resource(dev, res, &region);
1040 region.start = 0x3F6;
1041 region.end = 0x3F6;
1042 res = &dev->resource[1];
1043 res->flags = LEGACY_IO_RESOURCE;
1044 pcibios_bus_to_resource(dev, res, &region);
1046 if ((progif & 4) == 0) {
1047 region.start = 0x170;
1048 region.end = 0x177;
1049 res = &dev->resource[2];
1050 res->flags = LEGACY_IO_RESOURCE;
1051 pcibios_bus_to_resource(dev, res, &region);
1052 region.start = 0x376;
1053 region.end = 0x376;
1054 res = &dev->resource[3];
1055 res->flags = LEGACY_IO_RESOURCE;
1056 pcibios_bus_to_resource(dev, res, &region);
1059 break;
1061 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1062 if (class != PCI_CLASS_BRIDGE_PCI)
1063 goto bad;
1064 /* The PCI-to-PCI bridge spec requires that subtractive
1065 decoding (i.e. transparent) bridge must have programming
1066 interface code of 0x01. */
1067 pci_read_irq(dev);
1068 dev->transparent = ((dev->class & 0xff) == 1);
1069 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1070 set_pcie_hotplug_bridge(dev);
1071 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1072 if (pos) {
1073 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1074 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1076 break;
1078 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1079 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1080 goto bad;
1081 pci_read_irq(dev);
1082 pci_read_bases(dev, 1, 0);
1083 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1084 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1085 break;
1087 default: /* unknown header */
1088 dev_err(&dev->dev, "unknown header type %02x, "
1089 "ignoring device\n", dev->hdr_type);
1090 return -EIO;
1092 bad:
1093 dev_err(&dev->dev, "ignoring class %#08x (doesn't match header "
1094 "type %02x)\n", dev->class, dev->hdr_type);
1095 dev->class = PCI_CLASS_NOT_DEFINED;
1098 /* We found a fine healthy device, go go go... */
1099 return 0;
1102 static void pci_release_capabilities(struct pci_dev *dev)
1104 pci_vpd_release(dev);
1105 pci_iov_release(dev);
1106 pci_free_cap_save_buffers(dev);
1110 * pci_release_dev - free a pci device structure when all users of it are finished.
1111 * @dev: device that's been disconnected
1113 * Will be called only by the device core when all users of this pci device are
1114 * done.
1116 static void pci_release_dev(struct device *dev)
1118 struct pci_dev *pci_dev;
1120 pci_dev = to_pci_dev(dev);
1121 pci_release_capabilities(pci_dev);
1122 pci_release_of_node(pci_dev);
1123 kfree(pci_dev);
1127 * pci_cfg_space_size - get the configuration space size of the PCI device.
1128 * @dev: PCI device
1130 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1131 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1132 * access it. Maybe we don't have a way to generate extended config space
1133 * accesses, or the device is behind a reverse Express bridge. So we try
1134 * reading the dword at 0x100 which must either be 0 or a valid extended
1135 * capability header.
1137 int pci_cfg_space_size_ext(struct pci_dev *dev)
1139 u32 status;
1140 int pos = PCI_CFG_SPACE_SIZE;
1142 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1143 goto fail;
1144 if (status == 0xffffffff)
1145 goto fail;
1147 return PCI_CFG_SPACE_EXP_SIZE;
1149 fail:
1150 return PCI_CFG_SPACE_SIZE;
1153 int pci_cfg_space_size(struct pci_dev *dev)
1155 int pos;
1156 u32 status;
1157 u16 class;
1159 class = dev->class >> 8;
1160 if (class == PCI_CLASS_BRIDGE_HOST)
1161 return pci_cfg_space_size_ext(dev);
1163 pos = pci_pcie_cap(dev);
1164 if (!pos) {
1165 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1166 if (!pos)
1167 goto fail;
1169 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1170 if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
1171 goto fail;
1174 return pci_cfg_space_size_ext(dev);
1176 fail:
1177 return PCI_CFG_SPACE_SIZE;
1180 static void pci_release_bus_bridge_dev(struct device *dev)
1182 struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
1184 if (bridge->release_fn)
1185 bridge->release_fn(bridge);
1187 pci_free_resource_list(&bridge->windows);
1189 kfree(bridge);
1192 struct pci_dev *alloc_pci_dev(void)
1194 struct pci_dev *dev;
1196 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
1197 if (!dev)
1198 return NULL;
1200 INIT_LIST_HEAD(&dev->bus_list);
1202 return dev;
1204 EXPORT_SYMBOL(alloc_pci_dev);
1206 bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
1207 int crs_timeout)
1209 int delay = 1;
1211 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1212 return false;
1214 /* some broken boards return 0 or ~0 if a slot is empty: */
1215 if (*l == 0xffffffff || *l == 0x00000000 ||
1216 *l == 0x0000ffff || *l == 0xffff0000)
1217 return false;
1219 /* Configuration request Retry Status */
1220 while (*l == 0xffff0001) {
1221 if (!crs_timeout)
1222 return false;
1224 msleep(delay);
1225 delay *= 2;
1226 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1227 return false;
1228 /* Card hasn't responded in 60 seconds? Must be stuck. */
1229 if (delay > crs_timeout) {
1230 printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not "
1231 "responding\n", pci_domain_nr(bus),
1232 bus->number, PCI_SLOT(devfn),
1233 PCI_FUNC(devfn));
1234 return false;
1238 return true;
1240 EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
1243 * Read the config data for a PCI device, sanity-check it
1244 * and fill in the dev structure...
1246 static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
1248 struct pci_dev *dev;
1249 u32 l;
1251 if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
1252 return NULL;
1254 dev = alloc_pci_dev();
1255 if (!dev)
1256 return NULL;
1258 dev->bus = bus;
1259 dev->devfn = devfn;
1260 dev->vendor = l & 0xffff;
1261 dev->device = (l >> 16) & 0xffff;
1263 pci_set_of_node(dev);
1265 if (pci_setup_device(dev)) {
1266 kfree(dev);
1267 return NULL;
1270 return dev;
1273 static void pci_init_capabilities(struct pci_dev *dev)
1275 /* MSI/MSI-X list */
1276 pci_msi_init_pci_dev(dev);
1278 /* Buffers for saving PCIe and PCI-X capabilities */
1279 pci_allocate_cap_save_buffers(dev);
1281 /* Power Management */
1282 pci_pm_init(dev);
1283 platform_pci_wakeup_init(dev);
1285 /* Vital Product Data */
1286 pci_vpd_pci22_init(dev);
1288 /* Alternative Routing-ID Forwarding */
1289 pci_enable_ari(dev);
1291 /* Single Root I/O Virtualization */
1292 pci_iov_init(dev);
1294 /* Enable ACS P2P upstream forwarding */
1295 pci_enable_acs(dev);
1298 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
1300 device_initialize(&dev->dev);
1301 dev->dev.release = pci_release_dev;
1302 pci_dev_get(dev);
1304 dev->dev.dma_mask = &dev->dma_mask;
1305 dev->dev.dma_parms = &dev->dma_parms;
1306 dev->dev.coherent_dma_mask = 0xffffffffull;
1308 pci_set_dma_max_seg_size(dev, 65536);
1309 pci_set_dma_seg_boundary(dev, 0xffffffff);
1311 /* Fix up broken headers */
1312 pci_fixup_device(pci_fixup_header, dev);
1314 /* moved out from quirk header fixup code */
1315 pci_reassigndev_resource_alignment(dev);
1317 /* Clear the state_saved flag. */
1318 dev->state_saved = false;
1320 /* Initialize various capabilities */
1321 pci_init_capabilities(dev);
1324 * Add the device to our list of discovered devices
1325 * and the bus list for fixup functions, etc.
1327 down_write(&pci_bus_sem);
1328 list_add_tail(&dev->bus_list, &bus->devices);
1329 up_write(&pci_bus_sem);
1332 struct pci_dev *__ref pci_scan_single_device(struct pci_bus *bus, int devfn)
1334 struct pci_dev *dev;
1336 dev = pci_get_slot(bus, devfn);
1337 if (dev) {
1338 pci_dev_put(dev);
1339 return dev;
1342 dev = pci_scan_device(bus, devfn);
1343 if (!dev)
1344 return NULL;
1346 pci_device_add(dev, bus);
1348 return dev;
1350 EXPORT_SYMBOL(pci_scan_single_device);
1352 static unsigned next_ari_fn(struct pci_dev *dev, unsigned fn)
1354 u16 cap;
1355 unsigned pos, next_fn;
1357 if (!dev)
1358 return 0;
1360 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1361 if (!pos)
1362 return 0;
1363 pci_read_config_word(dev, pos + 4, &cap);
1364 next_fn = cap >> 8;
1365 if (next_fn <= fn)
1366 return 0;
1367 return next_fn;
1370 static unsigned next_trad_fn(struct pci_dev *dev, unsigned fn)
1372 return (fn + 1) % 8;
1375 static unsigned no_next_fn(struct pci_dev *dev, unsigned fn)
1377 return 0;
1380 static int only_one_child(struct pci_bus *bus)
1382 struct pci_dev *parent = bus->self;
1384 if (!parent || !pci_is_pcie(parent))
1385 return 0;
1386 if (parent->pcie_type == PCI_EXP_TYPE_ROOT_PORT)
1387 return 1;
1388 if (parent->pcie_type == PCI_EXP_TYPE_DOWNSTREAM &&
1389 !pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
1390 return 1;
1391 return 0;
1395 * pci_scan_slot - scan a PCI slot on a bus for devices.
1396 * @bus: PCI bus to scan
1397 * @devfn: slot number to scan (must have zero function.)
1399 * Scan a PCI slot on the specified PCI bus for devices, adding
1400 * discovered devices to the @bus->devices list. New devices
1401 * will not have is_added set.
1403 * Returns the number of new devices found.
1405 int pci_scan_slot(struct pci_bus *bus, int devfn)
1407 unsigned fn, nr = 0;
1408 struct pci_dev *dev;
1409 unsigned (*next_fn)(struct pci_dev *, unsigned) = no_next_fn;
1411 if (only_one_child(bus) && (devfn > 0))
1412 return 0; /* Already scanned the entire slot */
1414 dev = pci_scan_single_device(bus, devfn);
1415 if (!dev)
1416 return 0;
1417 if (!dev->is_added)
1418 nr++;
1420 if (pci_ari_enabled(bus))
1421 next_fn = next_ari_fn;
1422 else if (dev->multifunction)
1423 next_fn = next_trad_fn;
1425 for (fn = next_fn(dev, 0); fn > 0; fn = next_fn(dev, fn)) {
1426 dev = pci_scan_single_device(bus, devfn + fn);
1427 if (dev) {
1428 if (!dev->is_added)
1429 nr++;
1430 dev->multifunction = 1;
1434 /* only one slot has pcie device */
1435 if (bus->self && nr)
1436 pcie_aspm_init_link_state(bus->self);
1438 return nr;
1441 static int pcie_find_smpss(struct pci_dev *dev, void *data)
1443 u8 *smpss = data;
1445 if (!pci_is_pcie(dev))
1446 return 0;
1448 /* For PCIE hotplug enabled slots not connected directly to a
1449 * PCI-E root port, there can be problems when hotplugging
1450 * devices. This is due to the possibility of hotplugging a
1451 * device into the fabric with a smaller MPS that the devices
1452 * currently running have configured. Modifying the MPS on the
1453 * running devices could cause a fatal bus error due to an
1454 * incoming frame being larger than the newly configured MPS.
1455 * To work around this, the MPS for the entire fabric must be
1456 * set to the minimum size. Any devices hotplugged into this
1457 * fabric will have the minimum MPS set. If the PCI hotplug
1458 * slot is directly connected to the root port and there are not
1459 * other devices on the fabric (which seems to be the most
1460 * common case), then this is not an issue and MPS discovery
1461 * will occur as normal.
1463 if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) ||
1464 (dev->bus->self &&
1465 dev->bus->self->pcie_type != PCI_EXP_TYPE_ROOT_PORT)))
1466 *smpss = 0;
1468 if (*smpss > dev->pcie_mpss)
1469 *smpss = dev->pcie_mpss;
1471 return 0;
1474 static void pcie_write_mps(struct pci_dev *dev, int mps)
1476 int rc;
1478 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
1479 mps = 128 << dev->pcie_mpss;
1481 if (dev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && dev->bus->self)
1482 /* For "Performance", the assumption is made that
1483 * downstream communication will never be larger than
1484 * the MRRS. So, the MPS only needs to be configured
1485 * for the upstream communication. This being the case,
1486 * walk from the top down and set the MPS of the child
1487 * to that of the parent bus.
1489 * Configure the device MPS with the smaller of the
1490 * device MPSS or the bridge MPS (which is assumed to be
1491 * properly configured at this point to the largest
1492 * allowable MPS based on its parent bus).
1494 mps = min(mps, pcie_get_mps(dev->bus->self));
1497 rc = pcie_set_mps(dev, mps);
1498 if (rc)
1499 dev_err(&dev->dev, "Failed attempting to set the MPS\n");
1502 static void pcie_write_mrrs(struct pci_dev *dev)
1504 int rc, mrrs;
1506 /* In the "safe" case, do not configure the MRRS. There appear to be
1507 * issues with setting MRRS to 0 on a number of devices.
1509 if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
1510 return;
1512 /* For Max performance, the MRRS must be set to the largest supported
1513 * value. However, it cannot be configured larger than the MPS the
1514 * device or the bus can support. This should already be properly
1515 * configured by a prior call to pcie_write_mps.
1517 mrrs = pcie_get_mps(dev);
1519 /* MRRS is a R/W register. Invalid values can be written, but a
1520 * subsequent read will verify if the value is acceptable or not.
1521 * If the MRRS value provided is not acceptable (e.g., too large),
1522 * shrink the value until it is acceptable to the HW.
1524 while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
1525 rc = pcie_set_readrq(dev, mrrs);
1526 if (!rc)
1527 break;
1529 dev_warn(&dev->dev, "Failed attempting to set the MRRS\n");
1530 mrrs /= 2;
1533 if (mrrs < 128)
1534 dev_err(&dev->dev, "MRRS was unable to be configured with a "
1535 "safe value. If problems are experienced, try running "
1536 "with pci=pcie_bus_safe.\n");
1539 static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
1541 int mps, orig_mps;
1543 if (!pci_is_pcie(dev))
1544 return 0;
1546 mps = 128 << *(u8 *)data;
1547 orig_mps = pcie_get_mps(dev);
1549 pcie_write_mps(dev, mps);
1550 pcie_write_mrrs(dev);
1552 dev_info(&dev->dev, "PCI-E Max Payload Size set to %4d/%4d (was %4d), "
1553 "Max Read Rq %4d\n", pcie_get_mps(dev), 128 << dev->pcie_mpss,
1554 orig_mps, pcie_get_readrq(dev));
1556 return 0;
1559 /* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down,
1560 * parents then children fashion. If this changes, then this code will not
1561 * work as designed.
1563 void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss)
1565 u8 smpss;
1567 if (!pci_is_pcie(bus->self))
1568 return;
1570 if (pcie_bus_config == PCIE_BUS_TUNE_OFF)
1571 return;
1573 /* FIXME - Peer to peer DMA is possible, though the endpoint would need
1574 * to be aware to the MPS of the destination. To work around this,
1575 * simply force the MPS of the entire system to the smallest possible.
1577 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
1578 smpss = 0;
1580 if (pcie_bus_config == PCIE_BUS_SAFE) {
1581 smpss = mpss;
1583 pcie_find_smpss(bus->self, &smpss);
1584 pci_walk_bus(bus, pcie_find_smpss, &smpss);
1587 pcie_bus_configure_set(bus->self, &smpss);
1588 pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
1590 EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
1592 unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
1594 unsigned int devfn, pass, max = bus->busn_res.start;
1595 struct pci_dev *dev;
1597 dev_dbg(&bus->dev, "scanning bus\n");
1599 /* Go find them, Rover! */
1600 for (devfn = 0; devfn < 0x100; devfn += 8)
1601 pci_scan_slot(bus, devfn);
1603 /* Reserve buses for SR-IOV capability. */
1604 max += pci_iov_bus_range(bus);
1607 * After performing arch-dependent fixup of the bus, look behind
1608 * all PCI-to-PCI bridges on this bus.
1610 if (!bus->is_added) {
1611 dev_dbg(&bus->dev, "fixups for bus\n");
1612 pcibios_fixup_bus(bus);
1613 if (pci_is_root_bus(bus))
1614 bus->is_added = 1;
1617 for (pass=0; pass < 2; pass++)
1618 list_for_each_entry(dev, &bus->devices, bus_list) {
1619 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
1620 dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
1621 max = pci_scan_bridge(bus, dev, max, pass);
1625 * We've scanned the bus and so we know all about what's on
1626 * the other side of any bridges that may be on this bus plus
1627 * any devices.
1629 * Return how far we've got finding sub-buses.
1631 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
1632 return max;
1635 struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
1636 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1638 int error;
1639 struct pci_host_bridge *bridge;
1640 struct pci_bus *b, *b2;
1641 struct pci_host_bridge_window *window, *n;
1642 struct resource *res;
1643 resource_size_t offset;
1644 char bus_addr[64];
1645 char *fmt;
1648 b = pci_alloc_bus();
1649 if (!b)
1650 return NULL;
1652 b->sysdata = sysdata;
1653 b->ops = ops;
1654 b2 = pci_find_bus(pci_domain_nr(b), bus);
1655 if (b2) {
1656 /* If we already got to this bus through a different bridge, ignore it */
1657 dev_dbg(&b2->dev, "bus already known\n");
1658 goto err_out;
1661 bridge = pci_alloc_host_bridge(b);
1662 if (!bridge)
1663 goto err_out;
1665 bridge->dev.parent = parent;
1666 bridge->dev.release = pci_release_bus_bridge_dev;
1667 dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
1668 error = device_register(&bridge->dev);
1669 if (error)
1670 goto bridge_dev_reg_err;
1671 b->bridge = get_device(&bridge->dev);
1672 device_enable_async_suspend(b->bridge);
1673 pci_set_bus_of_node(b);
1675 if (!parent)
1676 set_dev_node(b->bridge, pcibus_to_node(b));
1678 b->dev.class = &pcibus_class;
1679 b->dev.parent = b->bridge;
1680 dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
1681 error = device_register(&b->dev);
1682 if (error)
1683 goto class_dev_reg_err;
1685 /* Create legacy_io and legacy_mem files for this bus */
1686 pci_create_legacy_files(b);
1688 b->number = b->busn_res.start = bus;
1690 if (parent)
1691 dev_info(parent, "PCI host bridge to bus %s\n", dev_name(&b->dev));
1692 else
1693 printk(KERN_INFO "PCI host bridge to bus %s\n", dev_name(&b->dev));
1695 /* Add initial resources to the bus */
1696 list_for_each_entry_safe(window, n, resources, list) {
1697 list_move_tail(&window->list, &bridge->windows);
1698 res = window->res;
1699 offset = window->offset;
1700 if (res->flags & IORESOURCE_BUS)
1701 pci_bus_insert_busn_res(b, bus, res->end);
1702 else
1703 pci_bus_add_resource(b, res, 0);
1704 if (offset) {
1705 if (resource_type(res) == IORESOURCE_IO)
1706 fmt = " (bus address [%#06llx-%#06llx])";
1707 else
1708 fmt = " (bus address [%#010llx-%#010llx])";
1709 snprintf(bus_addr, sizeof(bus_addr), fmt,
1710 (unsigned long long) (res->start - offset),
1711 (unsigned long long) (res->end - offset));
1712 } else
1713 bus_addr[0] = '\0';
1714 dev_info(&b->dev, "root bus resource %pR%s\n", res, bus_addr);
1717 down_write(&pci_bus_sem);
1718 list_add_tail(&b->node, &pci_root_buses);
1719 up_write(&pci_bus_sem);
1721 return b;
1723 class_dev_reg_err:
1724 put_device(&bridge->dev);
1725 device_unregister(&bridge->dev);
1726 bridge_dev_reg_err:
1727 kfree(bridge);
1728 err_out:
1729 kfree(b);
1730 return NULL;
1733 int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
1735 struct resource *res = &b->busn_res;
1736 struct resource *parent_res, *conflict;
1738 res->start = bus;
1739 res->end = bus_max;
1740 res->flags = IORESOURCE_BUS;
1742 if (!pci_is_root_bus(b))
1743 parent_res = &b->parent->busn_res;
1744 else {
1745 parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
1746 res->flags |= IORESOURCE_PCI_FIXED;
1749 conflict = insert_resource_conflict(parent_res, res);
1751 if (conflict)
1752 dev_printk(KERN_DEBUG, &b->dev,
1753 "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
1754 res, pci_is_root_bus(b) ? "domain " : "",
1755 parent_res, conflict->name, conflict);
1756 else
1757 dev_printk(KERN_DEBUG, &b->dev,
1758 "busn_res: %pR is inserted under %s%pR\n",
1759 res, pci_is_root_bus(b) ? "domain " : "",
1760 parent_res);
1762 return conflict == NULL;
1765 int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
1767 struct resource *res = &b->busn_res;
1768 struct resource old_res = *res;
1769 resource_size_t size;
1770 int ret;
1772 if (res->start > bus_max)
1773 return -EINVAL;
1775 size = bus_max - res->start + 1;
1776 ret = adjust_resource(res, res->start, size);
1777 dev_printk(KERN_DEBUG, &b->dev,
1778 "busn_res: %pR end %s updated to %02x\n",
1779 &old_res, ret ? "can not be" : "is", bus_max);
1781 if (!ret && !res->parent)
1782 pci_bus_insert_busn_res(b, res->start, res->end);
1784 return ret;
1787 void pci_bus_release_busn_res(struct pci_bus *b)
1789 struct resource *res = &b->busn_res;
1790 int ret;
1792 if (!res->flags || !res->parent)
1793 return;
1795 ret = release_resource(res);
1796 dev_printk(KERN_DEBUG, &b->dev,
1797 "busn_res: %pR %s released\n",
1798 res, ret ? "can not be" : "is");
1801 struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
1802 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1804 struct pci_host_bridge_window *window;
1805 bool found = false;
1806 struct pci_bus *b;
1807 int max;
1809 list_for_each_entry(window, resources, list)
1810 if (window->res->flags & IORESOURCE_BUS) {
1811 found = true;
1812 break;
1815 b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
1816 if (!b)
1817 return NULL;
1819 if (!found) {
1820 dev_info(&b->dev,
1821 "No busn resource found for root bus, will use [bus %02x-ff]\n",
1822 bus);
1823 pci_bus_insert_busn_res(b, bus, 255);
1826 max = pci_scan_child_bus(b);
1828 if (!found)
1829 pci_bus_update_busn_res_end(b, max);
1831 pci_bus_add_devices(b);
1832 return b;
1834 EXPORT_SYMBOL(pci_scan_root_bus);
1836 /* Deprecated; use pci_scan_root_bus() instead */
1837 struct pci_bus * __devinit pci_scan_bus_parented(struct device *parent,
1838 int bus, struct pci_ops *ops, void *sysdata)
1840 LIST_HEAD(resources);
1841 struct pci_bus *b;
1843 pci_add_resource(&resources, &ioport_resource);
1844 pci_add_resource(&resources, &iomem_resource);
1845 pci_add_resource(&resources, &busn_resource);
1846 b = pci_create_root_bus(parent, bus, ops, sysdata, &resources);
1847 if (b)
1848 pci_scan_child_bus(b);
1849 else
1850 pci_free_resource_list(&resources);
1851 return b;
1853 EXPORT_SYMBOL(pci_scan_bus_parented);
1855 struct pci_bus * __devinit pci_scan_bus(int bus, struct pci_ops *ops,
1856 void *sysdata)
1858 LIST_HEAD(resources);
1859 struct pci_bus *b;
1861 pci_add_resource(&resources, &ioport_resource);
1862 pci_add_resource(&resources, &iomem_resource);
1863 pci_add_resource(&resources, &busn_resource);
1864 b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
1865 if (b) {
1866 pci_scan_child_bus(b);
1867 pci_bus_add_devices(b);
1868 } else {
1869 pci_free_resource_list(&resources);
1871 return b;
1873 EXPORT_SYMBOL(pci_scan_bus);
1875 #ifdef CONFIG_HOTPLUG
1877 * pci_rescan_bus_bridge_resize - scan a PCI bus for devices.
1878 * @bridge: PCI bridge for the bus to scan
1880 * Scan a PCI bus and child buses for new devices, add them,
1881 * and enable them, resizing bridge mmio/io resource if necessary
1882 * and possible. The caller must ensure the child devices are already
1883 * removed for resizing to occur.
1885 * Returns the max number of subordinate bus discovered.
1887 unsigned int __ref pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
1889 unsigned int max;
1890 struct pci_bus *bus = bridge->subordinate;
1892 max = pci_scan_child_bus(bus);
1894 pci_assign_unassigned_bridge_resources(bridge);
1896 pci_bus_add_devices(bus);
1898 return max;
1901 EXPORT_SYMBOL(pci_add_new_bus);
1902 EXPORT_SYMBOL(pci_scan_slot);
1903 EXPORT_SYMBOL(pci_scan_bridge);
1904 EXPORT_SYMBOL_GPL(pci_scan_child_bus);
1905 #endif
1907 static int __init pci_sort_bf_cmp(const struct device *d_a, const struct device *d_b)
1909 const struct pci_dev *a = to_pci_dev(d_a);
1910 const struct pci_dev *b = to_pci_dev(d_b);
1912 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
1913 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
1915 if (a->bus->number < b->bus->number) return -1;
1916 else if (a->bus->number > b->bus->number) return 1;
1918 if (a->devfn < b->devfn) return -1;
1919 else if (a->devfn > b->devfn) return 1;
1921 return 0;
1924 void __init pci_sort_breadthfirst(void)
1926 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);