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1/*
2 * probe.c - PCI detection and setup code
3 */
4
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"
15
16#define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
17#define CARDBUS_RESERVE_BUSNR 3
18
19/* Ugh. Need to stop exporting this to modules. */
20LIST_HEAD(pci_root_buses);
21EXPORT_SYMBOL(pci_root_buses);
22
23static int find_anything(struct device *dev, void *data)
24{
25 return 1;
26}
27
28/*
29 * Some device drivers need know if pci is initiated.
30 * Basically, we think pci is not initiated when there
31 * is no device to be found on the pci_bus_type.
32 */
33int no_pci_devices(void)
34{
35 struct device *dev;
36 int no_devices;
37
38 dev = bus_find_device(&pci_bus_type, NULL, NULL, find_anything);
39 no_devices = (dev == NULL);
40 put_device(dev);
41 return no_devices;
42}
43EXPORT_SYMBOL(no_pci_devices);
44
45/*
46 * PCI Bus Class
47 */
48static void release_pcibus_dev(struct device *dev)
49{
50 struct pci_bus *pci_bus = to_pci_bus(dev);
51
52 if (pci_bus->bridge)
53 put_device(pci_bus->bridge);
54 pci_bus_remove_resources(pci_bus);
55 pci_release_bus_of_node(pci_bus);
56 kfree(pci_bus);
57}
58
59static struct class pcibus_class = {
60 .name = "pci_bus",
61 .dev_release = &release_pcibus_dev,
62 .dev_attrs = pcibus_dev_attrs,
63};
64
65static int __init pcibus_class_init(void)
66{
67 return class_register(&pcibus_class);
68}
69postcore_initcall(pcibus_class_init);
70
71static u64 pci_size(u64 base, u64 maxbase, u64 mask)
72{
73 u64 size = mask & maxbase; /* Find the significant bits */
74 if (!size)
75 return 0;
76
77 /* Get the lowest of them to find the decode size, and
78 from that the extent. */
79 size = (size & ~(size-1)) - 1;
80
81 /* base == maxbase can be valid only if the BAR has
82 already been programmed with all 1s. */
83 if (base == maxbase && ((base | size) & mask) != mask)
84 return 0;
85
86 return size;
87}
88
89static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
90{
91 u32 mem_type;
92 unsigned long flags;
93
94 if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
95 flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
96 flags |= IORESOURCE_IO;
97 return flags;
98 }
99
100 flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
101 flags |= IORESOURCE_MEM;
102 if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
103 flags |= IORESOURCE_PREFETCH;
104
105 mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
106 switch (mem_type) {
107 case PCI_BASE_ADDRESS_MEM_TYPE_32:
108 break;
109 case PCI_BASE_ADDRESS_MEM_TYPE_1M:
110 dev_info(&dev->dev, "1M mem BAR treated as 32-bit BAR\n");
111 break;
112 case PCI_BASE_ADDRESS_MEM_TYPE_64:
113 flags |= IORESOURCE_MEM_64;
114 break;
115 default:
116 dev_warn(&dev->dev,
117 "mem unknown type %x treated as 32-bit BAR\n",
118 mem_type);
119 break;
120 }
121 return flags;
122}
123
124/**
125 * pci_read_base - read a PCI BAR
126 * @dev: the PCI device
127 * @type: type of the BAR
128 * @res: resource buffer to be filled in
129 * @pos: BAR position in the config space
130 *
131 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
132 */
133int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
134 struct resource *res, unsigned int pos)
135{
136 u32 l, sz, mask;
137 u16 orig_cmd;
138 struct pci_bus_region region;
139
140 mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
141
142 if (!dev->mmio_always_on) {
143 pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
144 pci_write_config_word(dev, PCI_COMMAND,
145 orig_cmd & ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO));
146 }
147
148 res->name = pci_name(dev);
149
150 pci_read_config_dword(dev, pos, &l);
151 pci_write_config_dword(dev, pos, l | mask);
152 pci_read_config_dword(dev, pos, &sz);
153 pci_write_config_dword(dev, pos, l);
154
155 if (!dev->mmio_always_on)
156 pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
157
158 /*
159 * All bits set in sz means the device isn't working properly.
160 * If the BAR isn't implemented, all bits must be 0. If it's a
161 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
162 * 1 must be clear.
163 */
164 if (!sz || sz == 0xffffffff)
165 goto fail;
166
167 /*
168 * I don't know how l can have all bits set. Copied from old code.
169 * Maybe it fixes a bug on some ancient platform.
170 */
171 if (l == 0xffffffff)
172 l = 0;
173
174 if (type == pci_bar_unknown) {
175 res->flags = decode_bar(dev, l);
176 res->flags |= IORESOURCE_SIZEALIGN;
177 if (res->flags & IORESOURCE_IO) {
178 l &= PCI_BASE_ADDRESS_IO_MASK;
179 mask = PCI_BASE_ADDRESS_IO_MASK & (u32) IO_SPACE_LIMIT;
180 } else {
181 l &= PCI_BASE_ADDRESS_MEM_MASK;
182 mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
183 }
184 } else {
185 res->flags |= (l & IORESOURCE_ROM_ENABLE);
186 l &= PCI_ROM_ADDRESS_MASK;
187 mask = (u32)PCI_ROM_ADDRESS_MASK;
188 }
189
190 if (res->flags & IORESOURCE_MEM_64) {
191 u64 l64 = l;
192 u64 sz64 = sz;
193 u64 mask64 = mask | (u64)~0 << 32;
194
195 pci_read_config_dword(dev, pos + 4, &l);
196 pci_write_config_dword(dev, pos + 4, ~0);
197 pci_read_config_dword(dev, pos + 4, &sz);
198 pci_write_config_dword(dev, pos + 4, l);
199
200 l64 |= ((u64)l << 32);
201 sz64 |= ((u64)sz << 32);
202
203 sz64 = pci_size(l64, sz64, mask64);
204
205 if (!sz64)
206 goto fail;
207
208 if ((sizeof(resource_size_t) < 8) && (sz64 > 0x100000000ULL)) {
209 dev_err(&dev->dev, "reg %x: can't handle 64-bit BAR\n",
210 pos);
211 goto fail;
212 }
213
214 if ((sizeof(resource_size_t) < 8) && l) {
215 /* Address above 32-bit boundary; disable the BAR */
216 pci_write_config_dword(dev, pos, 0);
217 pci_write_config_dword(dev, pos + 4, 0);
218 region.start = 0;
219 region.end = sz64;
220 pcibios_bus_to_resource(dev, res, ®ion);
221 } else {
222 region.start = l64;
223 region.end = l64 + sz64;
224 pcibios_bus_to_resource(dev, res, ®ion);
225 dev_printk(KERN_DEBUG, &dev->dev, "reg %x: %pR\n",
226 pos, res);
227 }
228 } else {
229 sz = pci_size(l, sz, mask);
230
231 if (!sz)
232 goto fail;
233
234 region.start = l;
235 region.end = l + sz;
236 pcibios_bus_to_resource(dev, res, ®ion);
237
238 dev_printk(KERN_DEBUG, &dev->dev, "reg %x: %pR\n", pos, res);
239 }
240
241 out:
242 return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
243 fail:
244 res->flags = 0;
245 goto out;
246}
247
248static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
249{
250 unsigned int pos, reg;
251
252 for (pos = 0; pos < howmany; pos++) {
253 struct resource *res = &dev->resource[pos];
254 reg = PCI_BASE_ADDRESS_0 + (pos << 2);
255 pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
256 }
257
258 if (rom) {
259 struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
260 dev->rom_base_reg = rom;
261 res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
262 IORESOURCE_READONLY | IORESOURCE_CACHEABLE |
263 IORESOURCE_SIZEALIGN;
264 __pci_read_base(dev, pci_bar_mem32, res, rom);
265 }
266}
267
268static void __devinit pci_read_bridge_io(struct pci_bus *child)
269{
270 struct pci_dev *dev = child->self;
271 u8 io_base_lo, io_limit_lo;
272 unsigned long base, limit;
273 struct pci_bus_region region;
274 struct resource *res, res2;
275
276 res = child->resource[0];
277 pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
278 pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
279 base = (io_base_lo & PCI_IO_RANGE_MASK) << 8;
280 limit = (io_limit_lo & PCI_IO_RANGE_MASK) << 8;
281
282 if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
283 u16 io_base_hi, io_limit_hi;
284 pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
285 pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
286 base |= (io_base_hi << 16);
287 limit |= (io_limit_hi << 16);
288 }
289
290 if (base && base <= limit) {
291 res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
292 res2.flags = res->flags;
293 region.start = base;
294 region.end = limit + 0xfff;
295 pcibios_bus_to_resource(dev, &res2, ®ion);
296 if (!res->start)
297 res->start = res2.start;
298 if (!res->end)
299 res->end = res2.end;
300 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
301 }
302}
303
304static void __devinit pci_read_bridge_mmio(struct pci_bus *child)
305{
306 struct pci_dev *dev = child->self;
307 u16 mem_base_lo, mem_limit_lo;
308 unsigned long base, limit;
309 struct pci_bus_region region;
310 struct resource *res;
311
312 res = child->resource[1];
313 pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
314 pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
315 base = (mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
316 limit = (mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
317 if (base && base <= limit) {
318 res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
319 region.start = base;
320 region.end = limit + 0xfffff;
321 pcibios_bus_to_resource(dev, res, ®ion);
322 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
323 }
324}
325
326static void __devinit pci_read_bridge_mmio_pref(struct pci_bus *child)
327{
328 struct pci_dev *dev = child->self;
329 u16 mem_base_lo, mem_limit_lo;
330 unsigned long base, limit;
331 struct pci_bus_region region;
332 struct resource *res;
333
334 res = child->resource[2];
335 pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
336 pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
337 base = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
338 limit = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
339
340 if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
341 u32 mem_base_hi, mem_limit_hi;
342 pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
343 pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
344
345 /*
346 * Some bridges set the base > limit by default, and some
347 * (broken) BIOSes do not initialize them. If we find
348 * this, just assume they are not being used.
349 */
350 if (mem_base_hi <= mem_limit_hi) {
351#if BITS_PER_LONG == 64
352 base |= ((long) mem_base_hi) << 32;
353 limit |= ((long) mem_limit_hi) << 32;
354#else
355 if (mem_base_hi || mem_limit_hi) {
356 dev_err(&dev->dev, "can't handle 64-bit "
357 "address space for bridge\n");
358 return;
359 }
360#endif
361 }
362 }
363 if (base && base <= limit) {
364 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
365 IORESOURCE_MEM | IORESOURCE_PREFETCH;
366 if (res->flags & PCI_PREF_RANGE_TYPE_64)
367 res->flags |= IORESOURCE_MEM_64;
368 region.start = base;
369 region.end = limit + 0xfffff;
370 pcibios_bus_to_resource(dev, res, ®ion);
371 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
372 }
373}
374
375void __devinit pci_read_bridge_bases(struct pci_bus *child)
376{
377 struct pci_dev *dev = child->self;
378 struct resource *res;
379 int i;
380
381 if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
382 return;
383
384 dev_info(&dev->dev, "PCI bridge to [bus %02x-%02x]%s\n",
385 child->secondary, child->subordinate,
386 dev->transparent ? " (subtractive decode)" : "");
387
388 pci_bus_remove_resources(child);
389 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
390 child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
391
392 pci_read_bridge_io(child);
393 pci_read_bridge_mmio(child);
394 pci_read_bridge_mmio_pref(child);
395
396 if (dev->transparent) {
397 pci_bus_for_each_resource(child->parent, res, i) {
398 if (res) {
399 pci_bus_add_resource(child, res,
400 PCI_SUBTRACTIVE_DECODE);
401 dev_printk(KERN_DEBUG, &dev->dev,
402 " bridge window %pR (subtractive decode)\n",
403 res);
404 }
405 }
406 }
407}
408
409static struct pci_bus * pci_alloc_bus(void)
410{
411 struct pci_bus *b;
412
413 b = kzalloc(sizeof(*b), GFP_KERNEL);
414 if (b) {
415 INIT_LIST_HEAD(&b->node);
416 INIT_LIST_HEAD(&b->children);
417 INIT_LIST_HEAD(&b->devices);
418 INIT_LIST_HEAD(&b->slots);
419 INIT_LIST_HEAD(&b->resources);
420 b->max_bus_speed = PCI_SPEED_UNKNOWN;
421 b->cur_bus_speed = PCI_SPEED_UNKNOWN;
422 }
423 return b;
424}
425
426static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b)
427{
428 struct pci_host_bridge *bridge;
429
430 bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
431 if (bridge) {
432 INIT_LIST_HEAD(&bridge->windows);
433 bridge->bus = b;
434 }
435
436 return bridge;
437}
438
439static unsigned char pcix_bus_speed[] = {
440 PCI_SPEED_UNKNOWN, /* 0 */
441 PCI_SPEED_66MHz_PCIX, /* 1 */
442 PCI_SPEED_100MHz_PCIX, /* 2 */
443 PCI_SPEED_133MHz_PCIX, /* 3 */
444 PCI_SPEED_UNKNOWN, /* 4 */
445 PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
446 PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
447 PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
448 PCI_SPEED_UNKNOWN, /* 8 */
449 PCI_SPEED_66MHz_PCIX_266, /* 9 */
450 PCI_SPEED_100MHz_PCIX_266, /* A */
451 PCI_SPEED_133MHz_PCIX_266, /* B */
452 PCI_SPEED_UNKNOWN, /* C */
453 PCI_SPEED_66MHz_PCIX_533, /* D */
454 PCI_SPEED_100MHz_PCIX_533, /* E */
455 PCI_SPEED_133MHz_PCIX_533 /* F */
456};
457
458static unsigned char pcie_link_speed[] = {
459 PCI_SPEED_UNKNOWN, /* 0 */
460 PCIE_SPEED_2_5GT, /* 1 */
461 PCIE_SPEED_5_0GT, /* 2 */
462 PCIE_SPEED_8_0GT, /* 3 */
463 PCI_SPEED_UNKNOWN, /* 4 */
464 PCI_SPEED_UNKNOWN, /* 5 */
465 PCI_SPEED_UNKNOWN, /* 6 */
466 PCI_SPEED_UNKNOWN, /* 7 */
467 PCI_SPEED_UNKNOWN, /* 8 */
468 PCI_SPEED_UNKNOWN, /* 9 */
469 PCI_SPEED_UNKNOWN, /* A */
470 PCI_SPEED_UNKNOWN, /* B */
471 PCI_SPEED_UNKNOWN, /* C */
472 PCI_SPEED_UNKNOWN, /* D */
473 PCI_SPEED_UNKNOWN, /* E */
474 PCI_SPEED_UNKNOWN /* F */
475};
476
477void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
478{
479 bus->cur_bus_speed = pcie_link_speed[linksta & 0xf];
480}
481EXPORT_SYMBOL_GPL(pcie_update_link_speed);
482
483static unsigned char agp_speeds[] = {
484 AGP_UNKNOWN,
485 AGP_1X,
486 AGP_2X,
487 AGP_4X,
488 AGP_8X
489};
490
491static enum pci_bus_speed agp_speed(int agp3, int agpstat)
492{
493 int index = 0;
494
495 if (agpstat & 4)
496 index = 3;
497 else if (agpstat & 2)
498 index = 2;
499 else if (agpstat & 1)
500 index = 1;
501 else
502 goto out;
503
504 if (agp3) {
505 index += 2;
506 if (index == 5)
507 index = 0;
508 }
509
510 out:
511 return agp_speeds[index];
512}
513
514
515static void pci_set_bus_speed(struct pci_bus *bus)
516{
517 struct pci_dev *bridge = bus->self;
518 int pos;
519
520 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
521 if (!pos)
522 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
523 if (pos) {
524 u32 agpstat, agpcmd;
525
526 pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
527 bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
528
529 pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
530 bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
531 }
532
533 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
534 if (pos) {
535 u16 status;
536 enum pci_bus_speed max;
537 pci_read_config_word(bridge, pos + 2, &status);
538
539 if (status & 0x8000) {
540 max = PCI_SPEED_133MHz_PCIX_533;
541 } else if (status & 0x4000) {
542 max = PCI_SPEED_133MHz_PCIX_266;
543 } else if (status & 0x0002) {
544 if (((status >> 12) & 0x3) == 2) {
545 max = PCI_SPEED_133MHz_PCIX_ECC;
546 } else {
547 max = PCI_SPEED_133MHz_PCIX;
548 }
549 } else {
550 max = PCI_SPEED_66MHz_PCIX;
551 }
552
553 bus->max_bus_speed = max;
554 bus->cur_bus_speed = pcix_bus_speed[(status >> 6) & 0xf];
555
556 return;
557 }
558
559 pos = pci_find_capability(bridge, PCI_CAP_ID_EXP);
560 if (pos) {
561 u32 linkcap;
562 u16 linksta;
563
564 pci_read_config_dword(bridge, pos + PCI_EXP_LNKCAP, &linkcap);
565 bus->max_bus_speed = pcie_link_speed[linkcap & 0xf];
566
567 pci_read_config_word(bridge, pos + PCI_EXP_LNKSTA, &linksta);
568 pcie_update_link_speed(bus, linksta);
569 }
570}
571
572
573static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
574 struct pci_dev *bridge, int busnr)
575{
576 struct pci_bus *child;
577 int i;
578
579 /*
580 * Allocate a new bus, and inherit stuff from the parent..
581 */
582 child = pci_alloc_bus();
583 if (!child)
584 return NULL;
585
586 child->parent = parent;
587 child->ops = parent->ops;
588 child->sysdata = parent->sysdata;
589 child->bus_flags = parent->bus_flags;
590
591 /* initialize some portions of the bus device, but don't register it
592 * now as the parent is not properly set up yet. This device will get
593 * registered later in pci_bus_add_devices()
594 */
595 child->dev.class = &pcibus_class;
596 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
597
598 /*
599 * Set up the primary, secondary and subordinate
600 * bus numbers.
601 */
602 child->number = child->secondary = busnr;
603 child->primary = parent->secondary;
604 child->subordinate = 0xff;
605
606 if (!bridge)
607 return child;
608
609 child->self = bridge;
610 child->bridge = get_device(&bridge->dev);
611 pci_set_bus_of_node(child);
612 pci_set_bus_speed(child);
613
614 /* Set up default resource pointers and names.. */
615 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
616 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
617 child->resource[i]->name = child->name;
618 }
619 bridge->subordinate = child;
620
621 return child;
622}
623
624struct pci_bus *__ref pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr)
625{
626 struct pci_bus *child;
627
628 child = pci_alloc_child_bus(parent, dev, busnr);
629 if (child) {
630 down_write(&pci_bus_sem);
631 list_add_tail(&child->node, &parent->children);
632 up_write(&pci_bus_sem);
633 }
634 return child;
635}
636
637static void pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
638{
639 struct pci_bus *parent = child->parent;
640
641 /* Attempts to fix that up are really dangerous unless
642 we're going to re-assign all bus numbers. */
643 if (!pcibios_assign_all_busses())
644 return;
645
646 while (parent->parent && parent->subordinate < max) {
647 parent->subordinate = max;
648 pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);
649 parent = parent->parent;
650 }
651}
652
653/*
654 * If it's a bridge, configure it and scan the bus behind it.
655 * For CardBus bridges, we don't scan behind as the devices will
656 * be handled by the bridge driver itself.
657 *
658 * We need to process bridges in two passes -- first we scan those
659 * already configured by the BIOS and after we are done with all of
660 * them, we proceed to assigning numbers to the remaining buses in
661 * order to avoid overlaps between old and new bus numbers.
662 */
663int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
664{
665 struct pci_bus *child;
666 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
667 u32 buses, i, j = 0;
668 u16 bctl;
669 u8 primary, secondary, subordinate;
670 int broken = 0;
671
672 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
673 primary = buses & 0xFF;
674 secondary = (buses >> 8) & 0xFF;
675 subordinate = (buses >> 16) & 0xFF;
676
677 dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
678 secondary, subordinate, pass);
679
680 if (!primary && (primary != bus->number) && secondary && subordinate) {
681 dev_warn(&dev->dev, "Primary bus is hard wired to 0\n");
682 primary = bus->number;
683 }
684
685 /* Check if setup is sensible at all */
686 if (!pass &&
687 (primary != bus->number || secondary <= bus->number)) {
688 dev_dbg(&dev->dev, "bus configuration invalid, reconfiguring\n");
689 broken = 1;
690 }
691
692 /* Disable MasterAbortMode during probing to avoid reporting
693 of bus errors (in some architectures) */
694 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
695 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
696 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
697
698 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
699 !is_cardbus && !broken) {
700 unsigned int cmax;
701 /*
702 * Bus already configured by firmware, process it in the first
703 * pass and just note the configuration.
704 */
705 if (pass)
706 goto out;
707
708 /*
709 * If we already got to this bus through a different bridge,
710 * don't re-add it. This can happen with the i450NX chipset.
711 *
712 * However, we continue to descend down the hierarchy and
713 * scan remaining child buses.
714 */
715 child = pci_find_bus(pci_domain_nr(bus), secondary);
716 if (!child) {
717 child = pci_add_new_bus(bus, dev, secondary);
718 if (!child)
719 goto out;
720 child->primary = primary;
721 child->subordinate = subordinate;
722 child->bridge_ctl = bctl;
723 }
724
725 cmax = pci_scan_child_bus(child);
726 if (cmax > max)
727 max = cmax;
728 if (child->subordinate > max)
729 max = child->subordinate;
730 } else {
731 /*
732 * We need to assign a number to this bus which we always
733 * do in the second pass.
734 */
735 if (!pass) {
736 if (pcibios_assign_all_busses() || broken)
737 /* Temporarily disable forwarding of the
738 configuration cycles on all bridges in
739 this bus segment to avoid possible
740 conflicts in the second pass between two
741 bridges programmed with overlapping
742 bus ranges. */
743 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
744 buses & ~0xffffff);
745 goto out;
746 }
747
748 /* Clear errors */
749 pci_write_config_word(dev, PCI_STATUS, 0xffff);
750
751 /* Prevent assigning a bus number that already exists.
752 * This can happen when a bridge is hot-plugged, so in
753 * this case we only re-scan this bus. */
754 child = pci_find_bus(pci_domain_nr(bus), max+1);
755 if (!child) {
756 child = pci_add_new_bus(bus, dev, ++max);
757 if (!child)
758 goto out;
759 }
760 buses = (buses & 0xff000000)
761 | ((unsigned int)(child->primary) << 0)
762 | ((unsigned int)(child->secondary) << 8)
763 | ((unsigned int)(child->subordinate) << 16);
764
765 /*
766 * yenta.c forces a secondary latency timer of 176.
767 * Copy that behaviour here.
768 */
769 if (is_cardbus) {
770 buses &= ~0xff000000;
771 buses |= CARDBUS_LATENCY_TIMER << 24;
772 }
773
774 /*
775 * We need to blast all three values with a single write.
776 */
777 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
778
779 if (!is_cardbus) {
780 child->bridge_ctl = bctl;
781 /*
782 * Adjust subordinate busnr in parent buses.
783 * We do this before scanning for children because
784 * some devices may not be detected if the bios
785 * was lazy.
786 */
787 pci_fixup_parent_subordinate_busnr(child, max);
788 /* Now we can scan all subordinate buses... */
789 max = pci_scan_child_bus(child);
790 /*
791 * now fix it up again since we have found
792 * the real value of max.
793 */
794 pci_fixup_parent_subordinate_busnr(child, max);
795 } else {
796 /*
797 * For CardBus bridges, we leave 4 bus numbers
798 * as cards with a PCI-to-PCI bridge can be
799 * inserted later.
800 */
801 for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
802 struct pci_bus *parent = bus;
803 if (pci_find_bus(pci_domain_nr(bus),
804 max+i+1))
805 break;
806 while (parent->parent) {
807 if ((!pcibios_assign_all_busses()) &&
808 (parent->subordinate > max) &&
809 (parent->subordinate <= max+i)) {
810 j = 1;
811 }
812 parent = parent->parent;
813 }
814 if (j) {
815 /*
816 * Often, there are two cardbus bridges
817 * -- try to leave one valid bus number
818 * for each one.
819 */
820 i /= 2;
821 break;
822 }
823 }
824 max += i;
825 pci_fixup_parent_subordinate_busnr(child, max);
826 }
827 /*
828 * Set the subordinate bus number to its real value.
829 */
830 child->subordinate = max;
831 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
832 }
833
834 sprintf(child->name,
835 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
836 pci_domain_nr(bus), child->number);
837
838 /* Has only triggered on CardBus, fixup is in yenta_socket */
839 while (bus->parent) {
840 if ((child->subordinate > bus->subordinate) ||
841 (child->number > bus->subordinate) ||
842 (child->number < bus->number) ||
843 (child->subordinate < bus->number)) {
844 dev_info(&child->dev, "[bus %02x-%02x] %s "
845 "hidden behind%s bridge %s [bus %02x-%02x]\n",
846 child->number, child->subordinate,
847 (bus->number > child->subordinate &&
848 bus->subordinate < child->number) ?
849 "wholly" : "partially",
850 bus->self->transparent ? " transparent" : "",
851 dev_name(&bus->dev),
852 bus->number, bus->subordinate);
853 }
854 bus = bus->parent;
855 }
856
857out:
858 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
859
860 return max;
861}
862
863/*
864 * Read interrupt line and base address registers.
865 * The architecture-dependent code can tweak these, of course.
866 */
867static void pci_read_irq(struct pci_dev *dev)
868{
869 unsigned char irq;
870
871 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
872 dev->pin = irq;
873 if (irq)
874 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
875 dev->irq = irq;
876}
877
878void set_pcie_port_type(struct pci_dev *pdev)
879{
880 int pos;
881 u16 reg16;
882
883 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
884 if (!pos)
885 return;
886 pdev->is_pcie = 1;
887 pdev->pcie_cap = pos;
888 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
889 pdev->pcie_type = (reg16 & PCI_EXP_FLAGS_TYPE) >> 4;
890 pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16);
891 pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
892}
893
894void set_pcie_hotplug_bridge(struct pci_dev *pdev)
895{
896 int pos;
897 u16 reg16;
898 u32 reg32;
899
900 pos = pci_pcie_cap(pdev);
901 if (!pos)
902 return;
903 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
904 if (!(reg16 & PCI_EXP_FLAGS_SLOT))
905 return;
906 pci_read_config_dword(pdev, pos + PCI_EXP_SLTCAP, ®32);
907 if (reg32 & PCI_EXP_SLTCAP_HPC)
908 pdev->is_hotplug_bridge = 1;
909}
910
911#define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
912
913/**
914 * pci_setup_device - fill in class and map information of a device
915 * @dev: the device structure to fill
916 *
917 * Initialize the device structure with information about the device's
918 * vendor,class,memory and IO-space addresses,IRQ lines etc.
919 * Called at initialisation of the PCI subsystem and by CardBus services.
920 * Returns 0 on success and negative if unknown type of device (not normal,
921 * bridge or CardBus).
922 */
923int pci_setup_device(struct pci_dev *dev)
924{
925 u32 class;
926 u8 hdr_type;
927 struct pci_slot *slot;
928 int pos = 0;
929 struct pci_bus_region region;
930 struct resource *res;
931
932 if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
933 return -EIO;
934
935 dev->sysdata = dev->bus->sysdata;
936 dev->dev.parent = dev->bus->bridge;
937 dev->dev.bus = &pci_bus_type;
938 dev->hdr_type = hdr_type & 0x7f;
939 dev->multifunction = !!(hdr_type & 0x80);
940 dev->error_state = pci_channel_io_normal;
941 set_pcie_port_type(dev);
942
943 list_for_each_entry(slot, &dev->bus->slots, list)
944 if (PCI_SLOT(dev->devfn) == slot->number)
945 dev->slot = slot;
946
947 /* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
948 set this higher, assuming the system even supports it. */
949 dev->dma_mask = 0xffffffff;
950
951 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
952 dev->bus->number, PCI_SLOT(dev->devfn),
953 PCI_FUNC(dev->devfn));
954
955 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
956 dev->revision = class & 0xff;
957 dev->class = class >> 8; /* upper 3 bytes */
958
959 dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %02x class %#08x\n",
960 dev->vendor, dev->device, dev->hdr_type, dev->class);
961
962 /* need to have dev->class ready */
963 dev->cfg_size = pci_cfg_space_size(dev);
964
965 /* "Unknown power state" */
966 dev->current_state = PCI_UNKNOWN;
967
968 /* Early fixups, before probing the BARs */
969 pci_fixup_device(pci_fixup_early, dev);
970 /* device class may be changed after fixup */
971 class = dev->class >> 8;
972
973 switch (dev->hdr_type) { /* header type */
974 case PCI_HEADER_TYPE_NORMAL: /* standard header */
975 if (class == PCI_CLASS_BRIDGE_PCI)
976 goto bad;
977 pci_read_irq(dev);
978 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
979 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
980 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
981
982 /*
983 * Do the ugly legacy mode stuff here rather than broken chip
984 * quirk code. Legacy mode ATA controllers have fixed
985 * addresses. These are not always echoed in BAR0-3, and
986 * BAR0-3 in a few cases contain junk!
987 */
988 if (class == PCI_CLASS_STORAGE_IDE) {
989 u8 progif;
990 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
991 if ((progif & 1) == 0) {
992 region.start = 0x1F0;
993 region.end = 0x1F7;
994 res = &dev->resource[0];
995 res->flags = LEGACY_IO_RESOURCE;
996 pcibios_bus_to_resource(dev, res, ®ion);
997 region.start = 0x3F6;
998 region.end = 0x3F6;
999 res = &dev->resource[1];
1000 res->flags = LEGACY_IO_RESOURCE;
1001 pcibios_bus_to_resource(dev, res, ®ion);
1002 }
1003 if ((progif & 4) == 0) {
1004 region.start = 0x170;
1005 region.end = 0x177;
1006 res = &dev->resource[2];
1007 res->flags = LEGACY_IO_RESOURCE;
1008 pcibios_bus_to_resource(dev, res, ®ion);
1009 region.start = 0x376;
1010 region.end = 0x376;
1011 res = &dev->resource[3];
1012 res->flags = LEGACY_IO_RESOURCE;
1013 pcibios_bus_to_resource(dev, res, ®ion);
1014 }
1015 }
1016 break;
1017
1018 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1019 if (class != PCI_CLASS_BRIDGE_PCI)
1020 goto bad;
1021 /* The PCI-to-PCI bridge spec requires that subtractive
1022 decoding (i.e. transparent) bridge must have programming
1023 interface code of 0x01. */
1024 pci_read_irq(dev);
1025 dev->transparent = ((dev->class & 0xff) == 1);
1026 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1027 set_pcie_hotplug_bridge(dev);
1028 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1029 if (pos) {
1030 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1031 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1032 }
1033 break;
1034
1035 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1036 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1037 goto bad;
1038 pci_read_irq(dev);
1039 pci_read_bases(dev, 1, 0);
1040 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1041 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1042 break;
1043
1044 default: /* unknown header */
1045 dev_err(&dev->dev, "unknown header type %02x, "
1046 "ignoring device\n", dev->hdr_type);
1047 return -EIO;
1048
1049 bad:
1050 dev_err(&dev->dev, "ignoring class %#08x (doesn't match header "
1051 "type %02x)\n", dev->class, dev->hdr_type);
1052 dev->class = PCI_CLASS_NOT_DEFINED;
1053 }
1054
1055 /* We found a fine healthy device, go go go... */
1056 return 0;
1057}
1058
1059static void pci_release_capabilities(struct pci_dev *dev)
1060{
1061 pci_vpd_release(dev);
1062 pci_iov_release(dev);
1063 pci_free_cap_save_buffers(dev);
1064}
1065
1066/**
1067 * pci_release_dev - free a pci device structure when all users of it are finished.
1068 * @dev: device that's been disconnected
1069 *
1070 * Will be called only by the device core when all users of this pci device are
1071 * done.
1072 */
1073static void pci_release_dev(struct device *dev)
1074{
1075 struct pci_dev *pci_dev;
1076
1077 pci_dev = to_pci_dev(dev);
1078 pci_release_capabilities(pci_dev);
1079 pci_release_of_node(pci_dev);
1080 kfree(pci_dev);
1081}
1082
1083/**
1084 * pci_cfg_space_size - get the configuration space size of the PCI device.
1085 * @dev: PCI device
1086 *
1087 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1088 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1089 * access it. Maybe we don't have a way to generate extended config space
1090 * accesses, or the device is behind a reverse Express bridge. So we try
1091 * reading the dword at 0x100 which must either be 0 or a valid extended
1092 * capability header.
1093 */
1094int pci_cfg_space_size_ext(struct pci_dev *dev)
1095{
1096 u32 status;
1097 int pos = PCI_CFG_SPACE_SIZE;
1098
1099 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1100 goto fail;
1101 if (status == 0xffffffff)
1102 goto fail;
1103
1104 return PCI_CFG_SPACE_EXP_SIZE;
1105
1106 fail:
1107 return PCI_CFG_SPACE_SIZE;
1108}
1109
1110int pci_cfg_space_size(struct pci_dev *dev)
1111{
1112 int pos;
1113 u32 status;
1114 u16 class;
1115
1116 class = dev->class >> 8;
1117 if (class == PCI_CLASS_BRIDGE_HOST)
1118 return pci_cfg_space_size_ext(dev);
1119
1120 pos = pci_pcie_cap(dev);
1121 if (!pos) {
1122 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1123 if (!pos)
1124 goto fail;
1125
1126 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1127 if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
1128 goto fail;
1129 }
1130
1131 return pci_cfg_space_size_ext(dev);
1132
1133 fail:
1134 return PCI_CFG_SPACE_SIZE;
1135}
1136
1137static void pci_release_bus_bridge_dev(struct device *dev)
1138{
1139 struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
1140
1141 if (bridge->release_fn)
1142 bridge->release_fn(bridge);
1143
1144 pci_free_resource_list(&bridge->windows);
1145
1146 kfree(bridge);
1147}
1148
1149struct pci_dev *alloc_pci_dev(void)
1150{
1151 struct pci_dev *dev;
1152
1153 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
1154 if (!dev)
1155 return NULL;
1156
1157 INIT_LIST_HEAD(&dev->bus_list);
1158
1159 return dev;
1160}
1161EXPORT_SYMBOL(alloc_pci_dev);
1162
1163bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
1164 int crs_timeout)
1165{
1166 int delay = 1;
1167
1168 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1169 return false;
1170
1171 /* some broken boards return 0 or ~0 if a slot is empty: */
1172 if (*l == 0xffffffff || *l == 0x00000000 ||
1173 *l == 0x0000ffff || *l == 0xffff0000)
1174 return false;
1175
1176 /* Configuration request Retry Status */
1177 while (*l == 0xffff0001) {
1178 if (!crs_timeout)
1179 return false;
1180
1181 msleep(delay);
1182 delay *= 2;
1183 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1184 return false;
1185 /* Card hasn't responded in 60 seconds? Must be stuck. */
1186 if (delay > crs_timeout) {
1187 printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not "
1188 "responding\n", pci_domain_nr(bus),
1189 bus->number, PCI_SLOT(devfn),
1190 PCI_FUNC(devfn));
1191 return false;
1192 }
1193 }
1194
1195 return true;
1196}
1197EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
1198
1199/*
1200 * Read the config data for a PCI device, sanity-check it
1201 * and fill in the dev structure...
1202 */
1203static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
1204{
1205 struct pci_dev *dev;
1206 u32 l;
1207
1208 if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
1209 return NULL;
1210
1211 dev = alloc_pci_dev();
1212 if (!dev)
1213 return NULL;
1214
1215 dev->bus = bus;
1216 dev->devfn = devfn;
1217 dev->vendor = l & 0xffff;
1218 dev->device = (l >> 16) & 0xffff;
1219
1220 pci_set_of_node(dev);
1221
1222 if (pci_setup_device(dev)) {
1223 kfree(dev);
1224 return NULL;
1225 }
1226
1227 return dev;
1228}
1229
1230static void pci_init_capabilities(struct pci_dev *dev)
1231{
1232 /* MSI/MSI-X list */
1233 pci_msi_init_pci_dev(dev);
1234
1235 /* Buffers for saving PCIe and PCI-X capabilities */
1236 pci_allocate_cap_save_buffers(dev);
1237
1238 /* Power Management */
1239 pci_pm_init(dev);
1240 platform_pci_wakeup_init(dev);
1241
1242 /* Vital Product Data */
1243 pci_vpd_pci22_init(dev);
1244
1245 /* Alternative Routing-ID Forwarding */
1246 pci_enable_ari(dev);
1247
1248 /* Single Root I/O Virtualization */
1249 pci_iov_init(dev);
1250
1251 /* Enable ACS P2P upstream forwarding */
1252 pci_enable_acs(dev);
1253}
1254
1255void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
1256{
1257 device_initialize(&dev->dev);
1258 dev->dev.release = pci_release_dev;
1259 pci_dev_get(dev);
1260
1261 dev->dev.dma_mask = &dev->dma_mask;
1262 dev->dev.dma_parms = &dev->dma_parms;
1263 dev->dev.coherent_dma_mask = 0xffffffffull;
1264
1265 pci_set_dma_max_seg_size(dev, 65536);
1266 pci_set_dma_seg_boundary(dev, 0xffffffff);
1267
1268 /* Fix up broken headers */
1269 pci_fixup_device(pci_fixup_header, dev);
1270
1271 /* moved out from quirk header fixup code */
1272 pci_reassigndev_resource_alignment(dev);
1273
1274 /* Clear the state_saved flag. */
1275 dev->state_saved = false;
1276
1277 /* Initialize various capabilities */
1278 pci_init_capabilities(dev);
1279
1280 /*
1281 * Add the device to our list of discovered devices
1282 * and the bus list for fixup functions, etc.
1283 */
1284 down_write(&pci_bus_sem);
1285 list_add_tail(&dev->bus_list, &bus->devices);
1286 up_write(&pci_bus_sem);
1287}
1288
1289struct pci_dev *__ref pci_scan_single_device(struct pci_bus *bus, int devfn)
1290{
1291 struct pci_dev *dev;
1292
1293 dev = pci_get_slot(bus, devfn);
1294 if (dev) {
1295 pci_dev_put(dev);
1296 return dev;
1297 }
1298
1299 dev = pci_scan_device(bus, devfn);
1300 if (!dev)
1301 return NULL;
1302
1303 pci_device_add(dev, bus);
1304
1305 return dev;
1306}
1307EXPORT_SYMBOL(pci_scan_single_device);
1308
1309static unsigned next_ari_fn(struct pci_dev *dev, unsigned fn)
1310{
1311 u16 cap;
1312 unsigned pos, next_fn;
1313
1314 if (!dev)
1315 return 0;
1316
1317 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1318 if (!pos)
1319 return 0;
1320 pci_read_config_word(dev, pos + 4, &cap);
1321 next_fn = cap >> 8;
1322 if (next_fn <= fn)
1323 return 0;
1324 return next_fn;
1325}
1326
1327static unsigned next_trad_fn(struct pci_dev *dev, unsigned fn)
1328{
1329 return (fn + 1) % 8;
1330}
1331
1332static unsigned no_next_fn(struct pci_dev *dev, unsigned fn)
1333{
1334 return 0;
1335}
1336
1337static int only_one_child(struct pci_bus *bus)
1338{
1339 struct pci_dev *parent = bus->self;
1340
1341 if (!parent || !pci_is_pcie(parent))
1342 return 0;
1343 if (parent->pcie_type == PCI_EXP_TYPE_ROOT_PORT)
1344 return 1;
1345 if (parent->pcie_type == PCI_EXP_TYPE_DOWNSTREAM &&
1346 !pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
1347 return 1;
1348 return 0;
1349}
1350
1351/**
1352 * pci_scan_slot - scan a PCI slot on a bus for devices.
1353 * @bus: PCI bus to scan
1354 * @devfn: slot number to scan (must have zero function.)
1355 *
1356 * Scan a PCI slot on the specified PCI bus for devices, adding
1357 * discovered devices to the @bus->devices list. New devices
1358 * will not have is_added set.
1359 *
1360 * Returns the number of new devices found.
1361 */
1362int pci_scan_slot(struct pci_bus *bus, int devfn)
1363{
1364 unsigned fn, nr = 0;
1365 struct pci_dev *dev;
1366 unsigned (*next_fn)(struct pci_dev *, unsigned) = no_next_fn;
1367
1368 if (only_one_child(bus) && (devfn > 0))
1369 return 0; /* Already scanned the entire slot */
1370
1371 dev = pci_scan_single_device(bus, devfn);
1372 if (!dev)
1373 return 0;
1374 if (!dev->is_added)
1375 nr++;
1376
1377 if (pci_ari_enabled(bus))
1378 next_fn = next_ari_fn;
1379 else if (dev->multifunction)
1380 next_fn = next_trad_fn;
1381
1382 for (fn = next_fn(dev, 0); fn > 0; fn = next_fn(dev, fn)) {
1383 dev = pci_scan_single_device(bus, devfn + fn);
1384 if (dev) {
1385 if (!dev->is_added)
1386 nr++;
1387 dev->multifunction = 1;
1388 }
1389 }
1390
1391 /* only one slot has pcie device */
1392 if (bus->self && nr)
1393 pcie_aspm_init_link_state(bus->self);
1394
1395 return nr;
1396}
1397
1398static int pcie_find_smpss(struct pci_dev *dev, void *data)
1399{
1400 u8 *smpss = data;
1401
1402 if (!pci_is_pcie(dev))
1403 return 0;
1404
1405 /* For PCIE hotplug enabled slots not connected directly to a
1406 * PCI-E root port, there can be problems when hotplugging
1407 * devices. This is due to the possibility of hotplugging a
1408 * device into the fabric with a smaller MPS that the devices
1409 * currently running have configured. Modifying the MPS on the
1410 * running devices could cause a fatal bus error due to an
1411 * incoming frame being larger than the newly configured MPS.
1412 * To work around this, the MPS for the entire fabric must be
1413 * set to the minimum size. Any devices hotplugged into this
1414 * fabric will have the minimum MPS set. If the PCI hotplug
1415 * slot is directly connected to the root port and there are not
1416 * other devices on the fabric (which seems to be the most
1417 * common case), then this is not an issue and MPS discovery
1418 * will occur as normal.
1419 */
1420 if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) ||
1421 (dev->bus->self &&
1422 dev->bus->self->pcie_type != PCI_EXP_TYPE_ROOT_PORT)))
1423 *smpss = 0;
1424
1425 if (*smpss > dev->pcie_mpss)
1426 *smpss = dev->pcie_mpss;
1427
1428 return 0;
1429}
1430
1431static void pcie_write_mps(struct pci_dev *dev, int mps)
1432{
1433 int rc;
1434
1435 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
1436 mps = 128 << dev->pcie_mpss;
1437
1438 if (dev->pcie_type != PCI_EXP_TYPE_ROOT_PORT && dev->bus->self)
1439 /* For "Performance", the assumption is made that
1440 * downstream communication will never be larger than
1441 * the MRRS. So, the MPS only needs to be configured
1442 * for the upstream communication. This being the case,
1443 * walk from the top down and set the MPS of the child
1444 * to that of the parent bus.
1445 *
1446 * Configure the device MPS with the smaller of the
1447 * device MPSS or the bridge MPS (which is assumed to be
1448 * properly configured at this point to the largest
1449 * allowable MPS based on its parent bus).
1450 */
1451 mps = min(mps, pcie_get_mps(dev->bus->self));
1452 }
1453
1454 rc = pcie_set_mps(dev, mps);
1455 if (rc)
1456 dev_err(&dev->dev, "Failed attempting to set the MPS\n");
1457}
1458
1459static void pcie_write_mrrs(struct pci_dev *dev)
1460{
1461 int rc, mrrs;
1462
1463 /* In the "safe" case, do not configure the MRRS. There appear to be
1464 * issues with setting MRRS to 0 on a number of devices.
1465 */
1466 if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
1467 return;
1468
1469 /* For Max performance, the MRRS must be set to the largest supported
1470 * value. However, it cannot be configured larger than the MPS the
1471 * device or the bus can support. This should already be properly
1472 * configured by a prior call to pcie_write_mps.
1473 */
1474 mrrs = pcie_get_mps(dev);
1475
1476 /* MRRS is a R/W register. Invalid values can be written, but a
1477 * subsequent read will verify if the value is acceptable or not.
1478 * If the MRRS value provided is not acceptable (e.g., too large),
1479 * shrink the value until it is acceptable to the HW.
1480 */
1481 while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
1482 rc = pcie_set_readrq(dev, mrrs);
1483 if (!rc)
1484 break;
1485
1486 dev_warn(&dev->dev, "Failed attempting to set the MRRS\n");
1487 mrrs /= 2;
1488 }
1489
1490 if (mrrs < 128)
1491 dev_err(&dev->dev, "MRRS was unable to be configured with a "
1492 "safe value. If problems are experienced, try running "
1493 "with pci=pcie_bus_safe.\n");
1494}
1495
1496static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
1497{
1498 int mps, orig_mps;
1499
1500 if (!pci_is_pcie(dev))
1501 return 0;
1502
1503 mps = 128 << *(u8 *)data;
1504 orig_mps = pcie_get_mps(dev);
1505
1506 pcie_write_mps(dev, mps);
1507 pcie_write_mrrs(dev);
1508
1509 dev_info(&dev->dev, "PCI-E Max Payload Size set to %4d/%4d (was %4d), "
1510 "Max Read Rq %4d\n", pcie_get_mps(dev), 128 << dev->pcie_mpss,
1511 orig_mps, pcie_get_readrq(dev));
1512
1513 return 0;
1514}
1515
1516/* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down,
1517 * parents then children fashion. If this changes, then this code will not
1518 * work as designed.
1519 */
1520void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss)
1521{
1522 u8 smpss;
1523
1524 if (!pci_is_pcie(bus->self))
1525 return;
1526
1527 if (pcie_bus_config == PCIE_BUS_TUNE_OFF)
1528 return;
1529
1530 /* FIXME - Peer to peer DMA is possible, though the endpoint would need
1531 * to be aware to the MPS of the destination. To work around this,
1532 * simply force the MPS of the entire system to the smallest possible.
1533 */
1534 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
1535 smpss = 0;
1536
1537 if (pcie_bus_config == PCIE_BUS_SAFE) {
1538 smpss = mpss;
1539
1540 pcie_find_smpss(bus->self, &smpss);
1541 pci_walk_bus(bus, pcie_find_smpss, &smpss);
1542 }
1543
1544 pcie_bus_configure_set(bus->self, &smpss);
1545 pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
1546}
1547EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
1548
1549unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
1550{
1551 unsigned int devfn, pass, max = bus->secondary;
1552 struct pci_dev *dev;
1553
1554 dev_dbg(&bus->dev, "scanning bus\n");
1555
1556 /* Go find them, Rover! */
1557 for (devfn = 0; devfn < 0x100; devfn += 8)
1558 pci_scan_slot(bus, devfn);
1559
1560 /* Reserve buses for SR-IOV capability. */
1561 max += pci_iov_bus_range(bus);
1562
1563 /*
1564 * After performing arch-dependent fixup of the bus, look behind
1565 * all PCI-to-PCI bridges on this bus.
1566 */
1567 if (!bus->is_added) {
1568 dev_dbg(&bus->dev, "fixups for bus\n");
1569 pcibios_fixup_bus(bus);
1570 if (pci_is_root_bus(bus))
1571 bus->is_added = 1;
1572 }
1573
1574 for (pass=0; pass < 2; pass++)
1575 list_for_each_entry(dev, &bus->devices, bus_list) {
1576 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
1577 dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
1578 max = pci_scan_bridge(bus, dev, max, pass);
1579 }
1580
1581 /*
1582 * We've scanned the bus and so we know all about what's on
1583 * the other side of any bridges that may be on this bus plus
1584 * any devices.
1585 *
1586 * Return how far we've got finding sub-buses.
1587 */
1588 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
1589 return max;
1590}
1591
1592struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
1593 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1594{
1595 int error;
1596 struct pci_host_bridge *bridge;
1597 struct pci_bus *b, *b2;
1598 struct pci_host_bridge_window *window, *n;
1599 struct resource *res;
1600 resource_size_t offset;
1601 char bus_addr[64];
1602 char *fmt;
1603
1604
1605 b = pci_alloc_bus();
1606 if (!b)
1607 return NULL;
1608
1609 b->sysdata = sysdata;
1610 b->ops = ops;
1611 b2 = pci_find_bus(pci_domain_nr(b), bus);
1612 if (b2) {
1613 /* If we already got to this bus through a different bridge, ignore it */
1614 dev_dbg(&b2->dev, "bus already known\n");
1615 goto err_out;
1616 }
1617
1618 bridge = pci_alloc_host_bridge(b);
1619 if (!bridge)
1620 goto err_out;
1621
1622 bridge->dev.parent = parent;
1623 bridge->dev.release = pci_release_bus_bridge_dev;
1624 dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
1625 error = device_register(&bridge->dev);
1626 if (error)
1627 goto bridge_dev_reg_err;
1628 b->bridge = get_device(&bridge->dev);
1629 device_enable_async_suspend(b->bridge);
1630 pci_set_bus_of_node(b);
1631
1632 if (!parent)
1633 set_dev_node(b->bridge, pcibus_to_node(b));
1634
1635 b->dev.class = &pcibus_class;
1636 b->dev.parent = b->bridge;
1637 dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
1638 error = device_register(&b->dev);
1639 if (error)
1640 goto class_dev_reg_err;
1641
1642 /* Create legacy_io and legacy_mem files for this bus */
1643 pci_create_legacy_files(b);
1644
1645 b->number = b->secondary = bus;
1646
1647 if (parent)
1648 dev_info(parent, "PCI host bridge to bus %s\n", dev_name(&b->dev));
1649 else
1650 printk(KERN_INFO "PCI host bridge to bus %s\n", dev_name(&b->dev));
1651
1652 /* Add initial resources to the bus */
1653 list_for_each_entry_safe(window, n, resources, list) {
1654 list_move_tail(&window->list, &bridge->windows);
1655 res = window->res;
1656 offset = window->offset;
1657 pci_bus_add_resource(b, res, 0);
1658 if (offset) {
1659 if (resource_type(res) == IORESOURCE_IO)
1660 fmt = " (bus address [%#06llx-%#06llx])";
1661 else
1662 fmt = " (bus address [%#010llx-%#010llx])";
1663 snprintf(bus_addr, sizeof(bus_addr), fmt,
1664 (unsigned long long) (res->start - offset),
1665 (unsigned long long) (res->end - offset));
1666 } else
1667 bus_addr[0] = '\0';
1668 dev_info(&b->dev, "root bus resource %pR%s\n", res, bus_addr);
1669 }
1670
1671 down_write(&pci_bus_sem);
1672 list_add_tail(&b->node, &pci_root_buses);
1673 up_write(&pci_bus_sem);
1674
1675 return b;
1676
1677class_dev_reg_err:
1678 put_device(&bridge->dev);
1679 device_unregister(&bridge->dev);
1680bridge_dev_reg_err:
1681 kfree(bridge);
1682err_out:
1683 kfree(b);
1684 return NULL;
1685}
1686
1687struct pci_bus * __devinit pci_scan_root_bus(struct device *parent, int bus,
1688 struct pci_ops *ops, void *sysdata, struct list_head *resources)
1689{
1690 struct pci_bus *b;
1691
1692 b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
1693 if (!b)
1694 return NULL;
1695
1696 b->subordinate = pci_scan_child_bus(b);
1697 pci_bus_add_devices(b);
1698 return b;
1699}
1700EXPORT_SYMBOL(pci_scan_root_bus);
1701
1702/* Deprecated; use pci_scan_root_bus() instead */
1703struct pci_bus * __devinit pci_scan_bus_parented(struct device *parent,
1704 int bus, struct pci_ops *ops, void *sysdata)
1705{
1706 LIST_HEAD(resources);
1707 struct pci_bus *b;
1708
1709 pci_add_resource(&resources, &ioport_resource);
1710 pci_add_resource(&resources, &iomem_resource);
1711 b = pci_create_root_bus(parent, bus, ops, sysdata, &resources);
1712 if (b)
1713 b->subordinate = pci_scan_child_bus(b);
1714 else
1715 pci_free_resource_list(&resources);
1716 return b;
1717}
1718EXPORT_SYMBOL(pci_scan_bus_parented);
1719
1720struct pci_bus * __devinit pci_scan_bus(int bus, struct pci_ops *ops,
1721 void *sysdata)
1722{
1723 LIST_HEAD(resources);
1724 struct pci_bus *b;
1725
1726 pci_add_resource(&resources, &ioport_resource);
1727 pci_add_resource(&resources, &iomem_resource);
1728 b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
1729 if (b) {
1730 b->subordinate = pci_scan_child_bus(b);
1731 pci_bus_add_devices(b);
1732 } else {
1733 pci_free_resource_list(&resources);
1734 }
1735 return b;
1736}
1737EXPORT_SYMBOL(pci_scan_bus);
1738
1739#ifdef CONFIG_HOTPLUG
1740/**
1741 * pci_rescan_bus_bridge_resize - scan a PCI bus for devices.
1742 * @bridge: PCI bridge for the bus to scan
1743 *
1744 * Scan a PCI bus and child buses for new devices, add them,
1745 * and enable them, resizing bridge mmio/io resource if necessary
1746 * and possible. The caller must ensure the child devices are already
1747 * removed for resizing to occur.
1748 *
1749 * Returns the max number of subordinate bus discovered.
1750 */
1751unsigned int __ref pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
1752{
1753 unsigned int max;
1754 struct pci_bus *bus = bridge->subordinate;
1755
1756 max = pci_scan_child_bus(bus);
1757
1758 pci_assign_unassigned_bridge_resources(bridge);
1759
1760 pci_bus_add_devices(bus);
1761
1762 return max;
1763}
1764
1765EXPORT_SYMBOL(pci_add_new_bus);
1766EXPORT_SYMBOL(pci_scan_slot);
1767EXPORT_SYMBOL(pci_scan_bridge);
1768EXPORT_SYMBOL_GPL(pci_scan_child_bus);
1769#endif
1770
1771static int __init pci_sort_bf_cmp(const struct device *d_a, const struct device *d_b)
1772{
1773 const struct pci_dev *a = to_pci_dev(d_a);
1774 const struct pci_dev *b = to_pci_dev(d_b);
1775
1776 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
1777 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
1778
1779 if (a->bus->number < b->bus->number) return -1;
1780 else if (a->bus->number > b->bus->number) return 1;
1781
1782 if (a->devfn < b->devfn) return -1;
1783 else if (a->devfn > b->devfn) return 1;
1784
1785 return 0;
1786}
1787
1788void __init pci_sort_breadthfirst(void)
1789{
1790 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);
1791}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * PCI detection and setup code
4 */
5
6#include <linux/kernel.h>
7#include <linux/delay.h>
8#include <linux/init.h>
9#include <linux/pci.h>
10#include <linux/msi.h>
11#include <linux/of_device.h>
12#include <linux/of_pci.h>
13#include <linux/pci_hotplug.h>
14#include <linux/slab.h>
15#include <linux/module.h>
16#include <linux/cpumask.h>
17#include <linux/aer.h>
18#include <linux/acpi.h>
19#include <linux/hypervisor.h>
20#include <linux/irqdomain.h>
21#include <linux/pm_runtime.h>
22#include "pci.h"
23
24#define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
25#define CARDBUS_RESERVE_BUSNR 3
26
27static struct resource busn_resource = {
28 .name = "PCI busn",
29 .start = 0,
30 .end = 255,
31 .flags = IORESOURCE_BUS,
32};
33
34/* Ugh. Need to stop exporting this to modules. */
35LIST_HEAD(pci_root_buses);
36EXPORT_SYMBOL(pci_root_buses);
37
38static LIST_HEAD(pci_domain_busn_res_list);
39
40struct pci_domain_busn_res {
41 struct list_head list;
42 struct resource res;
43 int domain_nr;
44};
45
46static struct resource *get_pci_domain_busn_res(int domain_nr)
47{
48 struct pci_domain_busn_res *r;
49
50 list_for_each_entry(r, &pci_domain_busn_res_list, list)
51 if (r->domain_nr == domain_nr)
52 return &r->res;
53
54 r = kzalloc(sizeof(*r), GFP_KERNEL);
55 if (!r)
56 return NULL;
57
58 r->domain_nr = domain_nr;
59 r->res.start = 0;
60 r->res.end = 0xff;
61 r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
62
63 list_add_tail(&r->list, &pci_domain_busn_res_list);
64
65 return &r->res;
66}
67
68/*
69 * Some device drivers need know if PCI is initiated.
70 * Basically, we think PCI is not initiated when there
71 * is no device to be found on the pci_bus_type.
72 */
73int no_pci_devices(void)
74{
75 struct device *dev;
76 int no_devices;
77
78 dev = bus_find_next_device(&pci_bus_type, NULL);
79 no_devices = (dev == NULL);
80 put_device(dev);
81 return no_devices;
82}
83EXPORT_SYMBOL(no_pci_devices);
84
85/*
86 * PCI Bus Class
87 */
88static void release_pcibus_dev(struct device *dev)
89{
90 struct pci_bus *pci_bus = to_pci_bus(dev);
91
92 put_device(pci_bus->bridge);
93 pci_bus_remove_resources(pci_bus);
94 pci_release_bus_of_node(pci_bus);
95 kfree(pci_bus);
96}
97
98static struct class pcibus_class = {
99 .name = "pci_bus",
100 .dev_release = &release_pcibus_dev,
101 .dev_groups = pcibus_groups,
102};
103
104static int __init pcibus_class_init(void)
105{
106 return class_register(&pcibus_class);
107}
108postcore_initcall(pcibus_class_init);
109
110static u64 pci_size(u64 base, u64 maxbase, u64 mask)
111{
112 u64 size = mask & maxbase; /* Find the significant bits */
113 if (!size)
114 return 0;
115
116 /*
117 * Get the lowest of them to find the decode size, and from that
118 * the extent.
119 */
120 size = size & ~(size-1);
121
122 /*
123 * base == maxbase can be valid only if the BAR has already been
124 * programmed with all 1s.
125 */
126 if (base == maxbase && ((base | (size - 1)) & mask) != mask)
127 return 0;
128
129 return size;
130}
131
132static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
133{
134 u32 mem_type;
135 unsigned long flags;
136
137 if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
138 flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
139 flags |= IORESOURCE_IO;
140 return flags;
141 }
142
143 flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
144 flags |= IORESOURCE_MEM;
145 if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
146 flags |= IORESOURCE_PREFETCH;
147
148 mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
149 switch (mem_type) {
150 case PCI_BASE_ADDRESS_MEM_TYPE_32:
151 break;
152 case PCI_BASE_ADDRESS_MEM_TYPE_1M:
153 /* 1M mem BAR treated as 32-bit BAR */
154 break;
155 case PCI_BASE_ADDRESS_MEM_TYPE_64:
156 flags |= IORESOURCE_MEM_64;
157 break;
158 default:
159 /* mem unknown type treated as 32-bit BAR */
160 break;
161 }
162 return flags;
163}
164
165#define PCI_COMMAND_DECODE_ENABLE (PCI_COMMAND_MEMORY | PCI_COMMAND_IO)
166
167/**
168 * __pci_read_base - Read a PCI BAR
169 * @dev: the PCI device
170 * @type: type of the BAR
171 * @res: resource buffer to be filled in
172 * @pos: BAR position in the config space
173 *
174 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
175 */
176int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
177 struct resource *res, unsigned int pos)
178{
179 u32 l = 0, sz = 0, mask;
180 u64 l64, sz64, mask64;
181 u16 orig_cmd;
182 struct pci_bus_region region, inverted_region;
183
184 mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
185
186 /* No printks while decoding is disabled! */
187 if (!dev->mmio_always_on) {
188 pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
189 if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) {
190 pci_write_config_word(dev, PCI_COMMAND,
191 orig_cmd & ~PCI_COMMAND_DECODE_ENABLE);
192 }
193 }
194
195 res->name = pci_name(dev);
196
197 pci_read_config_dword(dev, pos, &l);
198 pci_write_config_dword(dev, pos, l | mask);
199 pci_read_config_dword(dev, pos, &sz);
200 pci_write_config_dword(dev, pos, l);
201
202 /*
203 * All bits set in sz means the device isn't working properly.
204 * If the BAR isn't implemented, all bits must be 0. If it's a
205 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
206 * 1 must be clear.
207 */
208 if (sz == 0xffffffff)
209 sz = 0;
210
211 /*
212 * I don't know how l can have all bits set. Copied from old code.
213 * Maybe it fixes a bug on some ancient platform.
214 */
215 if (l == 0xffffffff)
216 l = 0;
217
218 if (type == pci_bar_unknown) {
219 res->flags = decode_bar(dev, l);
220 res->flags |= IORESOURCE_SIZEALIGN;
221 if (res->flags & IORESOURCE_IO) {
222 l64 = l & PCI_BASE_ADDRESS_IO_MASK;
223 sz64 = sz & PCI_BASE_ADDRESS_IO_MASK;
224 mask64 = PCI_BASE_ADDRESS_IO_MASK & (u32)IO_SPACE_LIMIT;
225 } else {
226 l64 = l & PCI_BASE_ADDRESS_MEM_MASK;
227 sz64 = sz & PCI_BASE_ADDRESS_MEM_MASK;
228 mask64 = (u32)PCI_BASE_ADDRESS_MEM_MASK;
229 }
230 } else {
231 if (l & PCI_ROM_ADDRESS_ENABLE)
232 res->flags |= IORESOURCE_ROM_ENABLE;
233 l64 = l & PCI_ROM_ADDRESS_MASK;
234 sz64 = sz & PCI_ROM_ADDRESS_MASK;
235 mask64 = PCI_ROM_ADDRESS_MASK;
236 }
237
238 if (res->flags & IORESOURCE_MEM_64) {
239 pci_read_config_dword(dev, pos + 4, &l);
240 pci_write_config_dword(dev, pos + 4, ~0);
241 pci_read_config_dword(dev, pos + 4, &sz);
242 pci_write_config_dword(dev, pos + 4, l);
243
244 l64 |= ((u64)l << 32);
245 sz64 |= ((u64)sz << 32);
246 mask64 |= ((u64)~0 << 32);
247 }
248
249 if (!dev->mmio_always_on && (orig_cmd & PCI_COMMAND_DECODE_ENABLE))
250 pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
251
252 if (!sz64)
253 goto fail;
254
255 sz64 = pci_size(l64, sz64, mask64);
256 if (!sz64) {
257 pci_info(dev, FW_BUG "reg 0x%x: invalid BAR (can't size)\n",
258 pos);
259 goto fail;
260 }
261
262 if (res->flags & IORESOURCE_MEM_64) {
263 if ((sizeof(pci_bus_addr_t) < 8 || sizeof(resource_size_t) < 8)
264 && sz64 > 0x100000000ULL) {
265 res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
266 res->start = 0;
267 res->end = 0;
268 pci_err(dev, "reg 0x%x: can't handle BAR larger than 4GB (size %#010llx)\n",
269 pos, (unsigned long long)sz64);
270 goto out;
271 }
272
273 if ((sizeof(pci_bus_addr_t) < 8) && l) {
274 /* Above 32-bit boundary; try to reallocate */
275 res->flags |= IORESOURCE_UNSET;
276 res->start = 0;
277 res->end = sz64 - 1;
278 pci_info(dev, "reg 0x%x: can't handle BAR above 4GB (bus address %#010llx)\n",
279 pos, (unsigned long long)l64);
280 goto out;
281 }
282 }
283
284 region.start = l64;
285 region.end = l64 + sz64 - 1;
286
287 pcibios_bus_to_resource(dev->bus, res, ®ion);
288 pcibios_resource_to_bus(dev->bus, &inverted_region, res);
289
290 /*
291 * If "A" is a BAR value (a bus address), "bus_to_resource(A)" is
292 * the corresponding resource address (the physical address used by
293 * the CPU. Converting that resource address back to a bus address
294 * should yield the original BAR value:
295 *
296 * resource_to_bus(bus_to_resource(A)) == A
297 *
298 * If it doesn't, CPU accesses to "bus_to_resource(A)" will not
299 * be claimed by the device.
300 */
301 if (inverted_region.start != region.start) {
302 res->flags |= IORESOURCE_UNSET;
303 res->start = 0;
304 res->end = region.end - region.start;
305 pci_info(dev, "reg 0x%x: initial BAR value %#010llx invalid\n",
306 pos, (unsigned long long)region.start);
307 }
308
309 goto out;
310
311
312fail:
313 res->flags = 0;
314out:
315 if (res->flags)
316 pci_info(dev, "reg 0x%x: %pR\n", pos, res);
317
318 return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
319}
320
321static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
322{
323 unsigned int pos, reg;
324
325 if (dev->non_compliant_bars)
326 return;
327
328 /* Per PCIe r4.0, sec 9.3.4.1.11, the VF BARs are all RO Zero */
329 if (dev->is_virtfn)
330 return;
331
332 for (pos = 0; pos < howmany; pos++) {
333 struct resource *res = &dev->resource[pos];
334 reg = PCI_BASE_ADDRESS_0 + (pos << 2);
335 pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
336 }
337
338 if (rom) {
339 struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
340 dev->rom_base_reg = rom;
341 res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
342 IORESOURCE_READONLY | IORESOURCE_SIZEALIGN;
343 __pci_read_base(dev, pci_bar_mem32, res, rom);
344 }
345}
346
347static void pci_read_bridge_windows(struct pci_dev *bridge)
348{
349 u16 io;
350 u32 pmem, tmp;
351
352 pci_read_config_word(bridge, PCI_IO_BASE, &io);
353 if (!io) {
354 pci_write_config_word(bridge, PCI_IO_BASE, 0xe0f0);
355 pci_read_config_word(bridge, PCI_IO_BASE, &io);
356 pci_write_config_word(bridge, PCI_IO_BASE, 0x0);
357 }
358 if (io)
359 bridge->io_window = 1;
360
361 /*
362 * DECchip 21050 pass 2 errata: the bridge may miss an address
363 * disconnect boundary by one PCI data phase. Workaround: do not
364 * use prefetching on this device.
365 */
366 if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001)
367 return;
368
369 pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
370 if (!pmem) {
371 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE,
372 0xffe0fff0);
373 pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
374 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0);
375 }
376 if (!pmem)
377 return;
378
379 bridge->pref_window = 1;
380
381 if ((pmem & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
382
383 /*
384 * Bridge claims to have a 64-bit prefetchable memory
385 * window; verify that the upper bits are actually
386 * writable.
387 */
388 pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &pmem);
389 pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32,
390 0xffffffff);
391 pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &tmp);
392 pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, pmem);
393 if (tmp)
394 bridge->pref_64_window = 1;
395 }
396}
397
398static void pci_read_bridge_io(struct pci_bus *child)
399{
400 struct pci_dev *dev = child->self;
401 u8 io_base_lo, io_limit_lo;
402 unsigned long io_mask, io_granularity, base, limit;
403 struct pci_bus_region region;
404 struct resource *res;
405
406 io_mask = PCI_IO_RANGE_MASK;
407 io_granularity = 0x1000;
408 if (dev->io_window_1k) {
409 /* Support 1K I/O space granularity */
410 io_mask = PCI_IO_1K_RANGE_MASK;
411 io_granularity = 0x400;
412 }
413
414 res = child->resource[0];
415 pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
416 pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
417 base = (io_base_lo & io_mask) << 8;
418 limit = (io_limit_lo & io_mask) << 8;
419
420 if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
421 u16 io_base_hi, io_limit_hi;
422
423 pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
424 pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
425 base |= ((unsigned long) io_base_hi << 16);
426 limit |= ((unsigned long) io_limit_hi << 16);
427 }
428
429 if (base <= limit) {
430 res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
431 region.start = base;
432 region.end = limit + io_granularity - 1;
433 pcibios_bus_to_resource(dev->bus, res, ®ion);
434 pci_info(dev, " bridge window %pR\n", res);
435 }
436}
437
438static void pci_read_bridge_mmio(struct pci_bus *child)
439{
440 struct pci_dev *dev = child->self;
441 u16 mem_base_lo, mem_limit_lo;
442 unsigned long base, limit;
443 struct pci_bus_region region;
444 struct resource *res;
445
446 res = child->resource[1];
447 pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
448 pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
449 base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
450 limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
451 if (base <= limit) {
452 res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
453 region.start = base;
454 region.end = limit + 0xfffff;
455 pcibios_bus_to_resource(dev->bus, res, ®ion);
456 pci_info(dev, " bridge window %pR\n", res);
457 }
458}
459
460static void pci_read_bridge_mmio_pref(struct pci_bus *child)
461{
462 struct pci_dev *dev = child->self;
463 u16 mem_base_lo, mem_limit_lo;
464 u64 base64, limit64;
465 pci_bus_addr_t base, limit;
466 struct pci_bus_region region;
467 struct resource *res;
468
469 res = child->resource[2];
470 pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
471 pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
472 base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
473 limit64 = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
474
475 if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
476 u32 mem_base_hi, mem_limit_hi;
477
478 pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
479 pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
480
481 /*
482 * Some bridges set the base > limit by default, and some
483 * (broken) BIOSes do not initialize them. If we find
484 * this, just assume they are not being used.
485 */
486 if (mem_base_hi <= mem_limit_hi) {
487 base64 |= (u64) mem_base_hi << 32;
488 limit64 |= (u64) mem_limit_hi << 32;
489 }
490 }
491
492 base = (pci_bus_addr_t) base64;
493 limit = (pci_bus_addr_t) limit64;
494
495 if (base != base64) {
496 pci_err(dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
497 (unsigned long long) base64);
498 return;
499 }
500
501 if (base <= limit) {
502 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
503 IORESOURCE_MEM | IORESOURCE_PREFETCH;
504 if (res->flags & PCI_PREF_RANGE_TYPE_64)
505 res->flags |= IORESOURCE_MEM_64;
506 region.start = base;
507 region.end = limit + 0xfffff;
508 pcibios_bus_to_resource(dev->bus, res, ®ion);
509 pci_info(dev, " bridge window %pR\n", res);
510 }
511}
512
513void pci_read_bridge_bases(struct pci_bus *child)
514{
515 struct pci_dev *dev = child->self;
516 struct resource *res;
517 int i;
518
519 if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
520 return;
521
522 pci_info(dev, "PCI bridge to %pR%s\n",
523 &child->busn_res,
524 dev->transparent ? " (subtractive decode)" : "");
525
526 pci_bus_remove_resources(child);
527 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
528 child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
529
530 pci_read_bridge_io(child);
531 pci_read_bridge_mmio(child);
532 pci_read_bridge_mmio_pref(child);
533
534 if (dev->transparent) {
535 pci_bus_for_each_resource(child->parent, res, i) {
536 if (res && res->flags) {
537 pci_bus_add_resource(child, res,
538 PCI_SUBTRACTIVE_DECODE);
539 pci_info(dev, " bridge window %pR (subtractive decode)\n",
540 res);
541 }
542 }
543 }
544}
545
546static struct pci_bus *pci_alloc_bus(struct pci_bus *parent)
547{
548 struct pci_bus *b;
549
550 b = kzalloc(sizeof(*b), GFP_KERNEL);
551 if (!b)
552 return NULL;
553
554 INIT_LIST_HEAD(&b->node);
555 INIT_LIST_HEAD(&b->children);
556 INIT_LIST_HEAD(&b->devices);
557 INIT_LIST_HEAD(&b->slots);
558 INIT_LIST_HEAD(&b->resources);
559 b->max_bus_speed = PCI_SPEED_UNKNOWN;
560 b->cur_bus_speed = PCI_SPEED_UNKNOWN;
561#ifdef CONFIG_PCI_DOMAINS_GENERIC
562 if (parent)
563 b->domain_nr = parent->domain_nr;
564#endif
565 return b;
566}
567
568static void pci_release_host_bridge_dev(struct device *dev)
569{
570 struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
571
572 if (bridge->release_fn)
573 bridge->release_fn(bridge);
574
575 pci_free_resource_list(&bridge->windows);
576 pci_free_resource_list(&bridge->dma_ranges);
577 kfree(bridge);
578}
579
580static void pci_init_host_bridge(struct pci_host_bridge *bridge)
581{
582 INIT_LIST_HEAD(&bridge->windows);
583 INIT_LIST_HEAD(&bridge->dma_ranges);
584
585 /*
586 * We assume we can manage these PCIe features. Some systems may
587 * reserve these for use by the platform itself, e.g., an ACPI BIOS
588 * may implement its own AER handling and use _OSC to prevent the
589 * OS from interfering.
590 */
591 bridge->native_aer = 1;
592 bridge->native_pcie_hotplug = 1;
593 bridge->native_shpc_hotplug = 1;
594 bridge->native_pme = 1;
595 bridge->native_ltr = 1;
596 bridge->native_dpc = 1;
597
598 device_initialize(&bridge->dev);
599}
600
601struct pci_host_bridge *pci_alloc_host_bridge(size_t priv)
602{
603 struct pci_host_bridge *bridge;
604
605 bridge = kzalloc(sizeof(*bridge) + priv, GFP_KERNEL);
606 if (!bridge)
607 return NULL;
608
609 pci_init_host_bridge(bridge);
610 bridge->dev.release = pci_release_host_bridge_dev;
611
612 return bridge;
613}
614EXPORT_SYMBOL(pci_alloc_host_bridge);
615
616static void devm_pci_alloc_host_bridge_release(void *data)
617{
618 pci_free_host_bridge(data);
619}
620
621struct pci_host_bridge *devm_pci_alloc_host_bridge(struct device *dev,
622 size_t priv)
623{
624 int ret;
625 struct pci_host_bridge *bridge;
626
627 bridge = pci_alloc_host_bridge(priv);
628 if (!bridge)
629 return NULL;
630
631 bridge->dev.parent = dev;
632
633 ret = devm_add_action_or_reset(dev, devm_pci_alloc_host_bridge_release,
634 bridge);
635 if (ret)
636 return NULL;
637
638 ret = devm_of_pci_bridge_init(dev, bridge);
639 if (ret)
640 return NULL;
641
642 return bridge;
643}
644EXPORT_SYMBOL(devm_pci_alloc_host_bridge);
645
646void pci_free_host_bridge(struct pci_host_bridge *bridge)
647{
648 put_device(&bridge->dev);
649}
650EXPORT_SYMBOL(pci_free_host_bridge);
651
652/* Indexed by PCI_X_SSTATUS_FREQ (secondary bus mode and frequency) */
653static const unsigned char pcix_bus_speed[] = {
654 PCI_SPEED_UNKNOWN, /* 0 */
655 PCI_SPEED_66MHz_PCIX, /* 1 */
656 PCI_SPEED_100MHz_PCIX, /* 2 */
657 PCI_SPEED_133MHz_PCIX, /* 3 */
658 PCI_SPEED_UNKNOWN, /* 4 */
659 PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
660 PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
661 PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
662 PCI_SPEED_UNKNOWN, /* 8 */
663 PCI_SPEED_66MHz_PCIX_266, /* 9 */
664 PCI_SPEED_100MHz_PCIX_266, /* A */
665 PCI_SPEED_133MHz_PCIX_266, /* B */
666 PCI_SPEED_UNKNOWN, /* C */
667 PCI_SPEED_66MHz_PCIX_533, /* D */
668 PCI_SPEED_100MHz_PCIX_533, /* E */
669 PCI_SPEED_133MHz_PCIX_533 /* F */
670};
671
672/* Indexed by PCI_EXP_LNKCAP_SLS, PCI_EXP_LNKSTA_CLS */
673const unsigned char pcie_link_speed[] = {
674 PCI_SPEED_UNKNOWN, /* 0 */
675 PCIE_SPEED_2_5GT, /* 1 */
676 PCIE_SPEED_5_0GT, /* 2 */
677 PCIE_SPEED_8_0GT, /* 3 */
678 PCIE_SPEED_16_0GT, /* 4 */
679 PCIE_SPEED_32_0GT, /* 5 */
680 PCIE_SPEED_64_0GT, /* 6 */
681 PCI_SPEED_UNKNOWN, /* 7 */
682 PCI_SPEED_UNKNOWN, /* 8 */
683 PCI_SPEED_UNKNOWN, /* 9 */
684 PCI_SPEED_UNKNOWN, /* A */
685 PCI_SPEED_UNKNOWN, /* B */
686 PCI_SPEED_UNKNOWN, /* C */
687 PCI_SPEED_UNKNOWN, /* D */
688 PCI_SPEED_UNKNOWN, /* E */
689 PCI_SPEED_UNKNOWN /* F */
690};
691EXPORT_SYMBOL_GPL(pcie_link_speed);
692
693const char *pci_speed_string(enum pci_bus_speed speed)
694{
695 /* Indexed by the pci_bus_speed enum */
696 static const char *speed_strings[] = {
697 "33 MHz PCI", /* 0x00 */
698 "66 MHz PCI", /* 0x01 */
699 "66 MHz PCI-X", /* 0x02 */
700 "100 MHz PCI-X", /* 0x03 */
701 "133 MHz PCI-X", /* 0x04 */
702 NULL, /* 0x05 */
703 NULL, /* 0x06 */
704 NULL, /* 0x07 */
705 NULL, /* 0x08 */
706 "66 MHz PCI-X 266", /* 0x09 */
707 "100 MHz PCI-X 266", /* 0x0a */
708 "133 MHz PCI-X 266", /* 0x0b */
709 "Unknown AGP", /* 0x0c */
710 "1x AGP", /* 0x0d */
711 "2x AGP", /* 0x0e */
712 "4x AGP", /* 0x0f */
713 "8x AGP", /* 0x10 */
714 "66 MHz PCI-X 533", /* 0x11 */
715 "100 MHz PCI-X 533", /* 0x12 */
716 "133 MHz PCI-X 533", /* 0x13 */
717 "2.5 GT/s PCIe", /* 0x14 */
718 "5.0 GT/s PCIe", /* 0x15 */
719 "8.0 GT/s PCIe", /* 0x16 */
720 "16.0 GT/s PCIe", /* 0x17 */
721 "32.0 GT/s PCIe", /* 0x18 */
722 "64.0 GT/s PCIe", /* 0x19 */
723 };
724
725 if (speed < ARRAY_SIZE(speed_strings))
726 return speed_strings[speed];
727 return "Unknown";
728}
729EXPORT_SYMBOL_GPL(pci_speed_string);
730
731void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
732{
733 bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS];
734}
735EXPORT_SYMBOL_GPL(pcie_update_link_speed);
736
737static unsigned char agp_speeds[] = {
738 AGP_UNKNOWN,
739 AGP_1X,
740 AGP_2X,
741 AGP_4X,
742 AGP_8X
743};
744
745static enum pci_bus_speed agp_speed(int agp3, int agpstat)
746{
747 int index = 0;
748
749 if (agpstat & 4)
750 index = 3;
751 else if (agpstat & 2)
752 index = 2;
753 else if (agpstat & 1)
754 index = 1;
755 else
756 goto out;
757
758 if (agp3) {
759 index += 2;
760 if (index == 5)
761 index = 0;
762 }
763
764 out:
765 return agp_speeds[index];
766}
767
768static void pci_set_bus_speed(struct pci_bus *bus)
769{
770 struct pci_dev *bridge = bus->self;
771 int pos;
772
773 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
774 if (!pos)
775 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
776 if (pos) {
777 u32 agpstat, agpcmd;
778
779 pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
780 bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
781
782 pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
783 bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
784 }
785
786 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
787 if (pos) {
788 u16 status;
789 enum pci_bus_speed max;
790
791 pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
792 &status);
793
794 if (status & PCI_X_SSTATUS_533MHZ) {
795 max = PCI_SPEED_133MHz_PCIX_533;
796 } else if (status & PCI_X_SSTATUS_266MHZ) {
797 max = PCI_SPEED_133MHz_PCIX_266;
798 } else if (status & PCI_X_SSTATUS_133MHZ) {
799 if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2)
800 max = PCI_SPEED_133MHz_PCIX_ECC;
801 else
802 max = PCI_SPEED_133MHz_PCIX;
803 } else {
804 max = PCI_SPEED_66MHz_PCIX;
805 }
806
807 bus->max_bus_speed = max;
808 bus->cur_bus_speed = pcix_bus_speed[
809 (status & PCI_X_SSTATUS_FREQ) >> 6];
810
811 return;
812 }
813
814 if (pci_is_pcie(bridge)) {
815 u32 linkcap;
816 u16 linksta;
817
818 pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
819 bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
820 bridge->link_active_reporting = !!(linkcap & PCI_EXP_LNKCAP_DLLLARC);
821
822 pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
823 pcie_update_link_speed(bus, linksta);
824 }
825}
826
827static struct irq_domain *pci_host_bridge_msi_domain(struct pci_bus *bus)
828{
829 struct irq_domain *d;
830
831 /*
832 * Any firmware interface that can resolve the msi_domain
833 * should be called from here.
834 */
835 d = pci_host_bridge_of_msi_domain(bus);
836 if (!d)
837 d = pci_host_bridge_acpi_msi_domain(bus);
838
839#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
840 /*
841 * If no IRQ domain was found via the OF tree, try looking it up
842 * directly through the fwnode_handle.
843 */
844 if (!d) {
845 struct fwnode_handle *fwnode = pci_root_bus_fwnode(bus);
846
847 if (fwnode)
848 d = irq_find_matching_fwnode(fwnode,
849 DOMAIN_BUS_PCI_MSI);
850 }
851#endif
852
853 return d;
854}
855
856static void pci_set_bus_msi_domain(struct pci_bus *bus)
857{
858 struct irq_domain *d;
859 struct pci_bus *b;
860
861 /*
862 * The bus can be a root bus, a subordinate bus, or a virtual bus
863 * created by an SR-IOV device. Walk up to the first bridge device
864 * found or derive the domain from the host bridge.
865 */
866 for (b = bus, d = NULL; !d && !pci_is_root_bus(b); b = b->parent) {
867 if (b->self)
868 d = dev_get_msi_domain(&b->self->dev);
869 }
870
871 if (!d)
872 d = pci_host_bridge_msi_domain(b);
873
874 dev_set_msi_domain(&bus->dev, d);
875}
876
877static int pci_register_host_bridge(struct pci_host_bridge *bridge)
878{
879 struct device *parent = bridge->dev.parent;
880 struct resource_entry *window, *n;
881 struct pci_bus *bus, *b;
882 resource_size_t offset;
883 LIST_HEAD(resources);
884 struct resource *res;
885 char addr[64], *fmt;
886 const char *name;
887 int err;
888
889 bus = pci_alloc_bus(NULL);
890 if (!bus)
891 return -ENOMEM;
892
893 bridge->bus = bus;
894
895 /* Temporarily move resources off the list */
896 list_splice_init(&bridge->windows, &resources);
897 bus->sysdata = bridge->sysdata;
898 bus->ops = bridge->ops;
899 bus->number = bus->busn_res.start = bridge->busnr;
900#ifdef CONFIG_PCI_DOMAINS_GENERIC
901 bus->domain_nr = pci_bus_find_domain_nr(bus, parent);
902#endif
903
904 b = pci_find_bus(pci_domain_nr(bus), bridge->busnr);
905 if (b) {
906 /* Ignore it if we already got here via a different bridge */
907 dev_dbg(&b->dev, "bus already known\n");
908 err = -EEXIST;
909 goto free;
910 }
911
912 dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(bus),
913 bridge->busnr);
914
915 err = pcibios_root_bridge_prepare(bridge);
916 if (err)
917 goto free;
918
919 err = device_add(&bridge->dev);
920 if (err) {
921 put_device(&bridge->dev);
922 goto free;
923 }
924 bus->bridge = get_device(&bridge->dev);
925 device_enable_async_suspend(bus->bridge);
926 pci_set_bus_of_node(bus);
927 pci_set_bus_msi_domain(bus);
928 if (bridge->msi_domain && !dev_get_msi_domain(&bus->dev) &&
929 !pci_host_of_has_msi_map(parent))
930 bus->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
931
932 if (!parent)
933 set_dev_node(bus->bridge, pcibus_to_node(bus));
934
935 bus->dev.class = &pcibus_class;
936 bus->dev.parent = bus->bridge;
937
938 dev_set_name(&bus->dev, "%04x:%02x", pci_domain_nr(bus), bus->number);
939 name = dev_name(&bus->dev);
940
941 err = device_register(&bus->dev);
942 if (err)
943 goto unregister;
944
945 pcibios_add_bus(bus);
946
947 if (bus->ops->add_bus) {
948 err = bus->ops->add_bus(bus);
949 if (WARN_ON(err < 0))
950 dev_err(&bus->dev, "failed to add bus: %d\n", err);
951 }
952
953 /* Create legacy_io and legacy_mem files for this bus */
954 pci_create_legacy_files(bus);
955
956 if (parent)
957 dev_info(parent, "PCI host bridge to bus %s\n", name);
958 else
959 pr_info("PCI host bridge to bus %s\n", name);
960
961 if (nr_node_ids > 1 && pcibus_to_node(bus) == NUMA_NO_NODE)
962 dev_warn(&bus->dev, "Unknown NUMA node; performance will be reduced\n");
963
964 /* Add initial resources to the bus */
965 resource_list_for_each_entry_safe(window, n, &resources) {
966 list_move_tail(&window->node, &bridge->windows);
967 offset = window->offset;
968 res = window->res;
969
970 if (res->flags & IORESOURCE_BUS)
971 pci_bus_insert_busn_res(bus, bus->number, res->end);
972 else
973 pci_bus_add_resource(bus, res, 0);
974
975 if (offset) {
976 if (resource_type(res) == IORESOURCE_IO)
977 fmt = " (bus address [%#06llx-%#06llx])";
978 else
979 fmt = " (bus address [%#010llx-%#010llx])";
980
981 snprintf(addr, sizeof(addr), fmt,
982 (unsigned long long)(res->start - offset),
983 (unsigned long long)(res->end - offset));
984 } else
985 addr[0] = '\0';
986
987 dev_info(&bus->dev, "root bus resource %pR%s\n", res, addr);
988 }
989
990 down_write(&pci_bus_sem);
991 list_add_tail(&bus->node, &pci_root_buses);
992 up_write(&pci_bus_sem);
993
994 return 0;
995
996unregister:
997 put_device(&bridge->dev);
998 device_del(&bridge->dev);
999
1000free:
1001 kfree(bus);
1002 return err;
1003}
1004
1005static bool pci_bridge_child_ext_cfg_accessible(struct pci_dev *bridge)
1006{
1007 int pos;
1008 u32 status;
1009
1010 /*
1011 * If extended config space isn't accessible on a bridge's primary
1012 * bus, we certainly can't access it on the secondary bus.
1013 */
1014 if (bridge->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG)
1015 return false;
1016
1017 /*
1018 * PCIe Root Ports and switch ports are PCIe on both sides, so if
1019 * extended config space is accessible on the primary, it's also
1020 * accessible on the secondary.
1021 */
1022 if (pci_is_pcie(bridge) &&
1023 (pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT ||
1024 pci_pcie_type(bridge) == PCI_EXP_TYPE_UPSTREAM ||
1025 pci_pcie_type(bridge) == PCI_EXP_TYPE_DOWNSTREAM))
1026 return true;
1027
1028 /*
1029 * For the other bridge types:
1030 * - PCI-to-PCI bridges
1031 * - PCIe-to-PCI/PCI-X forward bridges
1032 * - PCI/PCI-X-to-PCIe reverse bridges
1033 * extended config space on the secondary side is only accessible
1034 * if the bridge supports PCI-X Mode 2.
1035 */
1036 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
1037 if (!pos)
1038 return false;
1039
1040 pci_read_config_dword(bridge, pos + PCI_X_STATUS, &status);
1041 return status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ);
1042}
1043
1044static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
1045 struct pci_dev *bridge, int busnr)
1046{
1047 struct pci_bus *child;
1048 struct pci_host_bridge *host;
1049 int i;
1050 int ret;
1051
1052 /* Allocate a new bus and inherit stuff from the parent */
1053 child = pci_alloc_bus(parent);
1054 if (!child)
1055 return NULL;
1056
1057 child->parent = parent;
1058 child->sysdata = parent->sysdata;
1059 child->bus_flags = parent->bus_flags;
1060
1061 host = pci_find_host_bridge(parent);
1062 if (host->child_ops)
1063 child->ops = host->child_ops;
1064 else
1065 child->ops = parent->ops;
1066
1067 /*
1068 * Initialize some portions of the bus device, but don't register
1069 * it now as the parent is not properly set up yet.
1070 */
1071 child->dev.class = &pcibus_class;
1072 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
1073
1074 /* Set up the primary, secondary and subordinate bus numbers */
1075 child->number = child->busn_res.start = busnr;
1076 child->primary = parent->busn_res.start;
1077 child->busn_res.end = 0xff;
1078
1079 if (!bridge) {
1080 child->dev.parent = parent->bridge;
1081 goto add_dev;
1082 }
1083
1084 child->self = bridge;
1085 child->bridge = get_device(&bridge->dev);
1086 child->dev.parent = child->bridge;
1087 pci_set_bus_of_node(child);
1088 pci_set_bus_speed(child);
1089
1090 /*
1091 * Check whether extended config space is accessible on the child
1092 * bus. Note that we currently assume it is always accessible on
1093 * the root bus.
1094 */
1095 if (!pci_bridge_child_ext_cfg_accessible(bridge)) {
1096 child->bus_flags |= PCI_BUS_FLAGS_NO_EXTCFG;
1097 pci_info(child, "extended config space not accessible\n");
1098 }
1099
1100 /* Set up default resource pointers and names */
1101 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
1102 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
1103 child->resource[i]->name = child->name;
1104 }
1105 bridge->subordinate = child;
1106
1107add_dev:
1108 pci_set_bus_msi_domain(child);
1109 ret = device_register(&child->dev);
1110 WARN_ON(ret < 0);
1111
1112 pcibios_add_bus(child);
1113
1114 if (child->ops->add_bus) {
1115 ret = child->ops->add_bus(child);
1116 if (WARN_ON(ret < 0))
1117 dev_err(&child->dev, "failed to add bus: %d\n", ret);
1118 }
1119
1120 /* Create legacy_io and legacy_mem files for this bus */
1121 pci_create_legacy_files(child);
1122
1123 return child;
1124}
1125
1126struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev,
1127 int busnr)
1128{
1129 struct pci_bus *child;
1130
1131 child = pci_alloc_child_bus(parent, dev, busnr);
1132 if (child) {
1133 down_write(&pci_bus_sem);
1134 list_add_tail(&child->node, &parent->children);
1135 up_write(&pci_bus_sem);
1136 }
1137 return child;
1138}
1139EXPORT_SYMBOL(pci_add_new_bus);
1140
1141static void pci_enable_crs(struct pci_dev *pdev)
1142{
1143 u16 root_cap = 0;
1144
1145 /* Enable CRS Software Visibility if supported */
1146 pcie_capability_read_word(pdev, PCI_EXP_RTCAP, &root_cap);
1147 if (root_cap & PCI_EXP_RTCAP_CRSVIS)
1148 pcie_capability_set_word(pdev, PCI_EXP_RTCTL,
1149 PCI_EXP_RTCTL_CRSSVE);
1150}
1151
1152static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
1153 unsigned int available_buses);
1154/**
1155 * pci_ea_fixed_busnrs() - Read fixed Secondary and Subordinate bus
1156 * numbers from EA capability.
1157 * @dev: Bridge
1158 * @sec: updated with secondary bus number from EA
1159 * @sub: updated with subordinate bus number from EA
1160 *
1161 * If @dev is a bridge with EA capability that specifies valid secondary
1162 * and subordinate bus numbers, return true with the bus numbers in @sec
1163 * and @sub. Otherwise return false.
1164 */
1165static bool pci_ea_fixed_busnrs(struct pci_dev *dev, u8 *sec, u8 *sub)
1166{
1167 int ea, offset;
1168 u32 dw;
1169 u8 ea_sec, ea_sub;
1170
1171 if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE)
1172 return false;
1173
1174 /* find PCI EA capability in list */
1175 ea = pci_find_capability(dev, PCI_CAP_ID_EA);
1176 if (!ea)
1177 return false;
1178
1179 offset = ea + PCI_EA_FIRST_ENT;
1180 pci_read_config_dword(dev, offset, &dw);
1181 ea_sec = dw & PCI_EA_SEC_BUS_MASK;
1182 ea_sub = (dw & PCI_EA_SUB_BUS_MASK) >> PCI_EA_SUB_BUS_SHIFT;
1183 if (ea_sec == 0 || ea_sub < ea_sec)
1184 return false;
1185
1186 *sec = ea_sec;
1187 *sub = ea_sub;
1188 return true;
1189}
1190
1191/*
1192 * pci_scan_bridge_extend() - Scan buses behind a bridge
1193 * @bus: Parent bus the bridge is on
1194 * @dev: Bridge itself
1195 * @max: Starting subordinate number of buses behind this bridge
1196 * @available_buses: Total number of buses available for this bridge and
1197 * the devices below. After the minimal bus space has
1198 * been allocated the remaining buses will be
1199 * distributed equally between hotplug-capable bridges.
1200 * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges
1201 * that need to be reconfigured.
1202 *
1203 * If it's a bridge, configure it and scan the bus behind it.
1204 * For CardBus bridges, we don't scan behind as the devices will
1205 * be handled by the bridge driver itself.
1206 *
1207 * We need to process bridges in two passes -- first we scan those
1208 * already configured by the BIOS and after we are done with all of
1209 * them, we proceed to assigning numbers to the remaining buses in
1210 * order to avoid overlaps between old and new bus numbers.
1211 *
1212 * Return: New subordinate number covering all buses behind this bridge.
1213 */
1214static int pci_scan_bridge_extend(struct pci_bus *bus, struct pci_dev *dev,
1215 int max, unsigned int available_buses,
1216 int pass)
1217{
1218 struct pci_bus *child;
1219 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
1220 u32 buses, i, j = 0;
1221 u16 bctl;
1222 u8 primary, secondary, subordinate;
1223 int broken = 0;
1224 bool fixed_buses;
1225 u8 fixed_sec, fixed_sub;
1226 int next_busnr;
1227
1228 /*
1229 * Make sure the bridge is powered on to be able to access config
1230 * space of devices below it.
1231 */
1232 pm_runtime_get_sync(&dev->dev);
1233
1234 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
1235 primary = buses & 0xFF;
1236 secondary = (buses >> 8) & 0xFF;
1237 subordinate = (buses >> 16) & 0xFF;
1238
1239 pci_dbg(dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
1240 secondary, subordinate, pass);
1241
1242 if (!primary && (primary != bus->number) && secondary && subordinate) {
1243 pci_warn(dev, "Primary bus is hard wired to 0\n");
1244 primary = bus->number;
1245 }
1246
1247 /* Check if setup is sensible at all */
1248 if (!pass &&
1249 (primary != bus->number || secondary <= bus->number ||
1250 secondary > subordinate)) {
1251 pci_info(dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
1252 secondary, subordinate);
1253 broken = 1;
1254 }
1255
1256 /*
1257 * Disable Master-Abort Mode during probing to avoid reporting of
1258 * bus errors in some architectures.
1259 */
1260 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
1261 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
1262 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
1263
1264 pci_enable_crs(dev);
1265
1266 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
1267 !is_cardbus && !broken) {
1268 unsigned int cmax;
1269
1270 /*
1271 * Bus already configured by firmware, process it in the
1272 * first pass and just note the configuration.
1273 */
1274 if (pass)
1275 goto out;
1276
1277 /*
1278 * The bus might already exist for two reasons: Either we
1279 * are rescanning the bus or the bus is reachable through
1280 * more than one bridge. The second case can happen with
1281 * the i450NX chipset.
1282 */
1283 child = pci_find_bus(pci_domain_nr(bus), secondary);
1284 if (!child) {
1285 child = pci_add_new_bus(bus, dev, secondary);
1286 if (!child)
1287 goto out;
1288 child->primary = primary;
1289 pci_bus_insert_busn_res(child, secondary, subordinate);
1290 child->bridge_ctl = bctl;
1291 }
1292
1293 cmax = pci_scan_child_bus(child);
1294 if (cmax > subordinate)
1295 pci_warn(dev, "bridge has subordinate %02x but max busn %02x\n",
1296 subordinate, cmax);
1297
1298 /* Subordinate should equal child->busn_res.end */
1299 if (subordinate > max)
1300 max = subordinate;
1301 } else {
1302
1303 /*
1304 * We need to assign a number to this bus which we always
1305 * do in the second pass.
1306 */
1307 if (!pass) {
1308 if (pcibios_assign_all_busses() || broken || is_cardbus)
1309
1310 /*
1311 * Temporarily disable forwarding of the
1312 * configuration cycles on all bridges in
1313 * this bus segment to avoid possible
1314 * conflicts in the second pass between two
1315 * bridges programmed with overlapping bus
1316 * ranges.
1317 */
1318 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
1319 buses & ~0xffffff);
1320 goto out;
1321 }
1322
1323 /* Clear errors */
1324 pci_write_config_word(dev, PCI_STATUS, 0xffff);
1325
1326 /* Read bus numbers from EA Capability (if present) */
1327 fixed_buses = pci_ea_fixed_busnrs(dev, &fixed_sec, &fixed_sub);
1328 if (fixed_buses)
1329 next_busnr = fixed_sec;
1330 else
1331 next_busnr = max + 1;
1332
1333 /*
1334 * Prevent assigning a bus number that already exists.
1335 * This can happen when a bridge is hot-plugged, so in this
1336 * case we only re-scan this bus.
1337 */
1338 child = pci_find_bus(pci_domain_nr(bus), next_busnr);
1339 if (!child) {
1340 child = pci_add_new_bus(bus, dev, next_busnr);
1341 if (!child)
1342 goto out;
1343 pci_bus_insert_busn_res(child, next_busnr,
1344 bus->busn_res.end);
1345 }
1346 max++;
1347 if (available_buses)
1348 available_buses--;
1349
1350 buses = (buses & 0xff000000)
1351 | ((unsigned int)(child->primary) << 0)
1352 | ((unsigned int)(child->busn_res.start) << 8)
1353 | ((unsigned int)(child->busn_res.end) << 16);
1354
1355 /*
1356 * yenta.c forces a secondary latency timer of 176.
1357 * Copy that behaviour here.
1358 */
1359 if (is_cardbus) {
1360 buses &= ~0xff000000;
1361 buses |= CARDBUS_LATENCY_TIMER << 24;
1362 }
1363
1364 /* We need to blast all three values with a single write */
1365 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
1366
1367 if (!is_cardbus) {
1368 child->bridge_ctl = bctl;
1369 max = pci_scan_child_bus_extend(child, available_buses);
1370 } else {
1371
1372 /*
1373 * For CardBus bridges, we leave 4 bus numbers as
1374 * cards with a PCI-to-PCI bridge can be inserted
1375 * later.
1376 */
1377 for (i = 0; i < CARDBUS_RESERVE_BUSNR; i++) {
1378 struct pci_bus *parent = bus;
1379 if (pci_find_bus(pci_domain_nr(bus),
1380 max+i+1))
1381 break;
1382 while (parent->parent) {
1383 if ((!pcibios_assign_all_busses()) &&
1384 (parent->busn_res.end > max) &&
1385 (parent->busn_res.end <= max+i)) {
1386 j = 1;
1387 }
1388 parent = parent->parent;
1389 }
1390 if (j) {
1391
1392 /*
1393 * Often, there are two CardBus
1394 * bridges -- try to leave one
1395 * valid bus number for each one.
1396 */
1397 i /= 2;
1398 break;
1399 }
1400 }
1401 max += i;
1402 }
1403
1404 /*
1405 * Set subordinate bus number to its real value.
1406 * If fixed subordinate bus number exists from EA
1407 * capability then use it.
1408 */
1409 if (fixed_buses)
1410 max = fixed_sub;
1411 pci_bus_update_busn_res_end(child, max);
1412 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
1413 }
1414
1415 sprintf(child->name,
1416 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
1417 pci_domain_nr(bus), child->number);
1418
1419 /* Check that all devices are accessible */
1420 while (bus->parent) {
1421 if ((child->busn_res.end > bus->busn_res.end) ||
1422 (child->number > bus->busn_res.end) ||
1423 (child->number < bus->number) ||
1424 (child->busn_res.end < bus->number)) {
1425 dev_info(&dev->dev, "devices behind bridge are unusable because %pR cannot be assigned for them\n",
1426 &child->busn_res);
1427 break;
1428 }
1429 bus = bus->parent;
1430 }
1431
1432out:
1433 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
1434
1435 pm_runtime_put(&dev->dev);
1436
1437 return max;
1438}
1439
1440/*
1441 * pci_scan_bridge() - Scan buses behind a bridge
1442 * @bus: Parent bus the bridge is on
1443 * @dev: Bridge itself
1444 * @max: Starting subordinate number of buses behind this bridge
1445 * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges
1446 * that need to be reconfigured.
1447 *
1448 * If it's a bridge, configure it and scan the bus behind it.
1449 * For CardBus bridges, we don't scan behind as the devices will
1450 * be handled by the bridge driver itself.
1451 *
1452 * We need to process bridges in two passes -- first we scan those
1453 * already configured by the BIOS and after we are done with all of
1454 * them, we proceed to assigning numbers to the remaining buses in
1455 * order to avoid overlaps between old and new bus numbers.
1456 *
1457 * Return: New subordinate number covering all buses behind this bridge.
1458 */
1459int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
1460{
1461 return pci_scan_bridge_extend(bus, dev, max, 0, pass);
1462}
1463EXPORT_SYMBOL(pci_scan_bridge);
1464
1465/*
1466 * Read interrupt line and base address registers.
1467 * The architecture-dependent code can tweak these, of course.
1468 */
1469static void pci_read_irq(struct pci_dev *dev)
1470{
1471 unsigned char irq;
1472
1473 /* VFs are not allowed to use INTx, so skip the config reads */
1474 if (dev->is_virtfn) {
1475 dev->pin = 0;
1476 dev->irq = 0;
1477 return;
1478 }
1479
1480 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
1481 dev->pin = irq;
1482 if (irq)
1483 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
1484 dev->irq = irq;
1485}
1486
1487void set_pcie_port_type(struct pci_dev *pdev)
1488{
1489 int pos;
1490 u16 reg16;
1491 int type;
1492 struct pci_dev *parent;
1493
1494 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
1495 if (!pos)
1496 return;
1497
1498 pdev->pcie_cap = pos;
1499 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
1500 pdev->pcie_flags_reg = reg16;
1501 pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16);
1502 pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
1503
1504 parent = pci_upstream_bridge(pdev);
1505 if (!parent)
1506 return;
1507
1508 /*
1509 * Some systems do not identify their upstream/downstream ports
1510 * correctly so detect impossible configurations here and correct
1511 * the port type accordingly.
1512 */
1513 type = pci_pcie_type(pdev);
1514 if (type == PCI_EXP_TYPE_DOWNSTREAM) {
1515 /*
1516 * If pdev claims to be downstream port but the parent
1517 * device is also downstream port assume pdev is actually
1518 * upstream port.
1519 */
1520 if (pcie_downstream_port(parent)) {
1521 pci_info(pdev, "claims to be downstream port but is acting as upstream port, correcting type\n");
1522 pdev->pcie_flags_reg &= ~PCI_EXP_FLAGS_TYPE;
1523 pdev->pcie_flags_reg |= PCI_EXP_TYPE_UPSTREAM;
1524 }
1525 } else if (type == PCI_EXP_TYPE_UPSTREAM) {
1526 /*
1527 * If pdev claims to be upstream port but the parent
1528 * device is also upstream port assume pdev is actually
1529 * downstream port.
1530 */
1531 if (pci_pcie_type(parent) == PCI_EXP_TYPE_UPSTREAM) {
1532 pci_info(pdev, "claims to be upstream port but is acting as downstream port, correcting type\n");
1533 pdev->pcie_flags_reg &= ~PCI_EXP_FLAGS_TYPE;
1534 pdev->pcie_flags_reg |= PCI_EXP_TYPE_DOWNSTREAM;
1535 }
1536 }
1537}
1538
1539void set_pcie_hotplug_bridge(struct pci_dev *pdev)
1540{
1541 u32 reg32;
1542
1543 pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32);
1544 if (reg32 & PCI_EXP_SLTCAP_HPC)
1545 pdev->is_hotplug_bridge = 1;
1546}
1547
1548static void set_pcie_thunderbolt(struct pci_dev *dev)
1549{
1550 int vsec = 0;
1551 u32 header;
1552
1553 while ((vsec = pci_find_next_ext_capability(dev, vsec,
1554 PCI_EXT_CAP_ID_VNDR))) {
1555 pci_read_config_dword(dev, vsec + PCI_VNDR_HEADER, &header);
1556
1557 /* Is the device part of a Thunderbolt controller? */
1558 if (dev->vendor == PCI_VENDOR_ID_INTEL &&
1559 PCI_VNDR_HEADER_ID(header) == PCI_VSEC_ID_INTEL_TBT) {
1560 dev->is_thunderbolt = 1;
1561 return;
1562 }
1563 }
1564}
1565
1566static void set_pcie_untrusted(struct pci_dev *dev)
1567{
1568 struct pci_dev *parent;
1569
1570 /*
1571 * If the upstream bridge is untrusted we treat this device
1572 * untrusted as well.
1573 */
1574 parent = pci_upstream_bridge(dev);
1575 if (parent && (parent->untrusted || parent->external_facing))
1576 dev->untrusted = true;
1577}
1578
1579static void pci_set_removable(struct pci_dev *dev)
1580{
1581 struct pci_dev *parent = pci_upstream_bridge(dev);
1582
1583 /*
1584 * We (only) consider everything downstream from an external_facing
1585 * device to be removable by the user. We're mainly concerned with
1586 * consumer platforms with user accessible thunderbolt ports that are
1587 * vulnerable to DMA attacks, and we expect those ports to be marked by
1588 * the firmware as external_facing. Devices in traditional hotplug
1589 * slots can technically be removed, but the expectation is that unless
1590 * the port is marked with external_facing, such devices are less
1591 * accessible to user / may not be removed by end user, and thus not
1592 * exposed as "removable" to userspace.
1593 */
1594 if (parent &&
1595 (parent->external_facing || dev_is_removable(&parent->dev)))
1596 dev_set_removable(&dev->dev, DEVICE_REMOVABLE);
1597}
1598
1599/**
1600 * pci_ext_cfg_is_aliased - Is ext config space just an alias of std config?
1601 * @dev: PCI device
1602 *
1603 * PCI Express to PCI/PCI-X Bridge Specification, rev 1.0, 4.1.4 says that
1604 * when forwarding a type1 configuration request the bridge must check that
1605 * the extended register address field is zero. The bridge is not permitted
1606 * to forward the transactions and must handle it as an Unsupported Request.
1607 * Some bridges do not follow this rule and simply drop the extended register
1608 * bits, resulting in the standard config space being aliased, every 256
1609 * bytes across the entire configuration space. Test for this condition by
1610 * comparing the first dword of each potential alias to the vendor/device ID.
1611 * Known offenders:
1612 * ASM1083/1085 PCIe-to-PCI Reversible Bridge (1b21:1080, rev 01 & 03)
1613 * AMD/ATI SBx00 PCI to PCI Bridge (1002:4384, rev 40)
1614 */
1615static bool pci_ext_cfg_is_aliased(struct pci_dev *dev)
1616{
1617#ifdef CONFIG_PCI_QUIRKS
1618 int pos;
1619 u32 header, tmp;
1620
1621 pci_read_config_dword(dev, PCI_VENDOR_ID, &header);
1622
1623 for (pos = PCI_CFG_SPACE_SIZE;
1624 pos < PCI_CFG_SPACE_EXP_SIZE; pos += PCI_CFG_SPACE_SIZE) {
1625 if (pci_read_config_dword(dev, pos, &tmp) != PCIBIOS_SUCCESSFUL
1626 || header != tmp)
1627 return false;
1628 }
1629
1630 return true;
1631#else
1632 return false;
1633#endif
1634}
1635
1636/**
1637 * pci_cfg_space_size_ext - Get the configuration space size of the PCI device
1638 * @dev: PCI device
1639 *
1640 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1641 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1642 * access it. Maybe we don't have a way to generate extended config space
1643 * accesses, or the device is behind a reverse Express bridge. So we try
1644 * reading the dword at 0x100 which must either be 0 or a valid extended
1645 * capability header.
1646 */
1647static int pci_cfg_space_size_ext(struct pci_dev *dev)
1648{
1649 u32 status;
1650 int pos = PCI_CFG_SPACE_SIZE;
1651
1652 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1653 return PCI_CFG_SPACE_SIZE;
1654 if (status == 0xffffffff || pci_ext_cfg_is_aliased(dev))
1655 return PCI_CFG_SPACE_SIZE;
1656
1657 return PCI_CFG_SPACE_EXP_SIZE;
1658}
1659
1660int pci_cfg_space_size(struct pci_dev *dev)
1661{
1662 int pos;
1663 u32 status;
1664 u16 class;
1665
1666#ifdef CONFIG_PCI_IOV
1667 /*
1668 * Per the SR-IOV specification (rev 1.1, sec 3.5), VFs are required to
1669 * implement a PCIe capability and therefore must implement extended
1670 * config space. We can skip the NO_EXTCFG test below and the
1671 * reachability/aliasing test in pci_cfg_space_size_ext() by virtue of
1672 * the fact that the SR-IOV capability on the PF resides in extended
1673 * config space and must be accessible and non-aliased to have enabled
1674 * support for this VF. This is a micro performance optimization for
1675 * systems supporting many VFs.
1676 */
1677 if (dev->is_virtfn)
1678 return PCI_CFG_SPACE_EXP_SIZE;
1679#endif
1680
1681 if (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG)
1682 return PCI_CFG_SPACE_SIZE;
1683
1684 class = dev->class >> 8;
1685 if (class == PCI_CLASS_BRIDGE_HOST)
1686 return pci_cfg_space_size_ext(dev);
1687
1688 if (pci_is_pcie(dev))
1689 return pci_cfg_space_size_ext(dev);
1690
1691 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1692 if (!pos)
1693 return PCI_CFG_SPACE_SIZE;
1694
1695 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1696 if (status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ))
1697 return pci_cfg_space_size_ext(dev);
1698
1699 return PCI_CFG_SPACE_SIZE;
1700}
1701
1702static u32 pci_class(struct pci_dev *dev)
1703{
1704 u32 class;
1705
1706#ifdef CONFIG_PCI_IOV
1707 if (dev->is_virtfn)
1708 return dev->physfn->sriov->class;
1709#endif
1710 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
1711 return class;
1712}
1713
1714static void pci_subsystem_ids(struct pci_dev *dev, u16 *vendor, u16 *device)
1715{
1716#ifdef CONFIG_PCI_IOV
1717 if (dev->is_virtfn) {
1718 *vendor = dev->physfn->sriov->subsystem_vendor;
1719 *device = dev->physfn->sriov->subsystem_device;
1720 return;
1721 }
1722#endif
1723 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, vendor);
1724 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, device);
1725}
1726
1727static u8 pci_hdr_type(struct pci_dev *dev)
1728{
1729 u8 hdr_type;
1730
1731#ifdef CONFIG_PCI_IOV
1732 if (dev->is_virtfn)
1733 return dev->physfn->sriov->hdr_type;
1734#endif
1735 pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type);
1736 return hdr_type;
1737}
1738
1739#define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
1740
1741/**
1742 * pci_intx_mask_broken - Test PCI_COMMAND_INTX_DISABLE writability
1743 * @dev: PCI device
1744 *
1745 * Test whether PCI_COMMAND_INTX_DISABLE is writable for @dev. Check this
1746 * at enumeration-time to avoid modifying PCI_COMMAND at run-time.
1747 */
1748static int pci_intx_mask_broken(struct pci_dev *dev)
1749{
1750 u16 orig, toggle, new;
1751
1752 pci_read_config_word(dev, PCI_COMMAND, &orig);
1753 toggle = orig ^ PCI_COMMAND_INTX_DISABLE;
1754 pci_write_config_word(dev, PCI_COMMAND, toggle);
1755 pci_read_config_word(dev, PCI_COMMAND, &new);
1756
1757 pci_write_config_word(dev, PCI_COMMAND, orig);
1758
1759 /*
1760 * PCI_COMMAND_INTX_DISABLE was reserved and read-only prior to PCI
1761 * r2.3, so strictly speaking, a device is not *broken* if it's not
1762 * writable. But we'll live with the misnomer for now.
1763 */
1764 if (new != toggle)
1765 return 1;
1766 return 0;
1767}
1768
1769static void early_dump_pci_device(struct pci_dev *pdev)
1770{
1771 u32 value[256 / 4];
1772 int i;
1773
1774 pci_info(pdev, "config space:\n");
1775
1776 for (i = 0; i < 256; i += 4)
1777 pci_read_config_dword(pdev, i, &value[i / 4]);
1778
1779 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 1,
1780 value, 256, false);
1781}
1782
1783/**
1784 * pci_setup_device - Fill in class and map information of a device
1785 * @dev: the device structure to fill
1786 *
1787 * Initialize the device structure with information about the device's
1788 * vendor,class,memory and IO-space addresses, IRQ lines etc.
1789 * Called at initialisation of the PCI subsystem and by CardBus services.
1790 * Returns 0 on success and negative if unknown type of device (not normal,
1791 * bridge or CardBus).
1792 */
1793int pci_setup_device(struct pci_dev *dev)
1794{
1795 u32 class;
1796 u16 cmd;
1797 u8 hdr_type;
1798 int pos = 0;
1799 struct pci_bus_region region;
1800 struct resource *res;
1801
1802 hdr_type = pci_hdr_type(dev);
1803
1804 dev->sysdata = dev->bus->sysdata;
1805 dev->dev.parent = dev->bus->bridge;
1806 dev->dev.bus = &pci_bus_type;
1807 dev->hdr_type = hdr_type & 0x7f;
1808 dev->multifunction = !!(hdr_type & 0x80);
1809 dev->error_state = pci_channel_io_normal;
1810 set_pcie_port_type(dev);
1811
1812 pci_dev_assign_slot(dev);
1813
1814 /*
1815 * Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
1816 * set this higher, assuming the system even supports it.
1817 */
1818 dev->dma_mask = 0xffffffff;
1819
1820 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
1821 dev->bus->number, PCI_SLOT(dev->devfn),
1822 PCI_FUNC(dev->devfn));
1823
1824 class = pci_class(dev);
1825
1826 dev->revision = class & 0xff;
1827 dev->class = class >> 8; /* upper 3 bytes */
1828
1829 if (pci_early_dump)
1830 early_dump_pci_device(dev);
1831
1832 /* Need to have dev->class ready */
1833 dev->cfg_size = pci_cfg_space_size(dev);
1834
1835 /* Need to have dev->cfg_size ready */
1836 set_pcie_thunderbolt(dev);
1837
1838 set_pcie_untrusted(dev);
1839
1840 /* "Unknown power state" */
1841 dev->current_state = PCI_UNKNOWN;
1842
1843 /* Early fixups, before probing the BARs */
1844 pci_fixup_device(pci_fixup_early, dev);
1845
1846 pci_set_removable(dev);
1847
1848 pci_info(dev, "[%04x:%04x] type %02x class %#08x\n",
1849 dev->vendor, dev->device, dev->hdr_type, dev->class);
1850
1851 /* Device class may be changed after fixup */
1852 class = dev->class >> 8;
1853
1854 if (dev->non_compliant_bars && !dev->mmio_always_on) {
1855 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1856 if (cmd & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) {
1857 pci_info(dev, "device has non-compliant BARs; disabling IO/MEM decoding\n");
1858 cmd &= ~PCI_COMMAND_IO;
1859 cmd &= ~PCI_COMMAND_MEMORY;
1860 pci_write_config_word(dev, PCI_COMMAND, cmd);
1861 }
1862 }
1863
1864 dev->broken_intx_masking = pci_intx_mask_broken(dev);
1865
1866 switch (dev->hdr_type) { /* header type */
1867 case PCI_HEADER_TYPE_NORMAL: /* standard header */
1868 if (class == PCI_CLASS_BRIDGE_PCI)
1869 goto bad;
1870 pci_read_irq(dev);
1871 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1872
1873 pci_subsystem_ids(dev, &dev->subsystem_vendor, &dev->subsystem_device);
1874
1875 /*
1876 * Do the ugly legacy mode stuff here rather than broken chip
1877 * quirk code. Legacy mode ATA controllers have fixed
1878 * addresses. These are not always echoed in BAR0-3, and
1879 * BAR0-3 in a few cases contain junk!
1880 */
1881 if (class == PCI_CLASS_STORAGE_IDE) {
1882 u8 progif;
1883 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1884 if ((progif & 1) == 0) {
1885 region.start = 0x1F0;
1886 region.end = 0x1F7;
1887 res = &dev->resource[0];
1888 res->flags = LEGACY_IO_RESOURCE;
1889 pcibios_bus_to_resource(dev->bus, res, ®ion);
1890 pci_info(dev, "legacy IDE quirk: reg 0x10: %pR\n",
1891 res);
1892 region.start = 0x3F6;
1893 region.end = 0x3F6;
1894 res = &dev->resource[1];
1895 res->flags = LEGACY_IO_RESOURCE;
1896 pcibios_bus_to_resource(dev->bus, res, ®ion);
1897 pci_info(dev, "legacy IDE quirk: reg 0x14: %pR\n",
1898 res);
1899 }
1900 if ((progif & 4) == 0) {
1901 region.start = 0x170;
1902 region.end = 0x177;
1903 res = &dev->resource[2];
1904 res->flags = LEGACY_IO_RESOURCE;
1905 pcibios_bus_to_resource(dev->bus, res, ®ion);
1906 pci_info(dev, "legacy IDE quirk: reg 0x18: %pR\n",
1907 res);
1908 region.start = 0x376;
1909 region.end = 0x376;
1910 res = &dev->resource[3];
1911 res->flags = LEGACY_IO_RESOURCE;
1912 pcibios_bus_to_resource(dev->bus, res, ®ion);
1913 pci_info(dev, "legacy IDE quirk: reg 0x1c: %pR\n",
1914 res);
1915 }
1916 }
1917 break;
1918
1919 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1920 /*
1921 * The PCI-to-PCI bridge spec requires that subtractive
1922 * decoding (i.e. transparent) bridge must have programming
1923 * interface code of 0x01.
1924 */
1925 pci_read_irq(dev);
1926 dev->transparent = ((dev->class & 0xff) == 1);
1927 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1928 pci_read_bridge_windows(dev);
1929 set_pcie_hotplug_bridge(dev);
1930 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1931 if (pos) {
1932 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1933 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1934 }
1935 break;
1936
1937 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1938 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1939 goto bad;
1940 pci_read_irq(dev);
1941 pci_read_bases(dev, 1, 0);
1942 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1943 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1944 break;
1945
1946 default: /* unknown header */
1947 pci_err(dev, "unknown header type %02x, ignoring device\n",
1948 dev->hdr_type);
1949 return -EIO;
1950
1951 bad:
1952 pci_err(dev, "ignoring class %#08x (doesn't match header type %02x)\n",
1953 dev->class, dev->hdr_type);
1954 dev->class = PCI_CLASS_NOT_DEFINED << 8;
1955 }
1956
1957 /* We found a fine healthy device, go go go... */
1958 return 0;
1959}
1960
1961static void pci_configure_mps(struct pci_dev *dev)
1962{
1963 struct pci_dev *bridge = pci_upstream_bridge(dev);
1964 int mps, mpss, p_mps, rc;
1965
1966 if (!pci_is_pcie(dev))
1967 return;
1968
1969 /* MPS and MRRS fields are of type 'RsvdP' for VFs, short-circuit out */
1970 if (dev->is_virtfn)
1971 return;
1972
1973 /*
1974 * For Root Complex Integrated Endpoints, program the maximum
1975 * supported value unless limited by the PCIE_BUS_PEER2PEER case.
1976 */
1977 if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) {
1978 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
1979 mps = 128;
1980 else
1981 mps = 128 << dev->pcie_mpss;
1982 rc = pcie_set_mps(dev, mps);
1983 if (rc) {
1984 pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
1985 mps);
1986 }
1987 return;
1988 }
1989
1990 if (!bridge || !pci_is_pcie(bridge))
1991 return;
1992
1993 mps = pcie_get_mps(dev);
1994 p_mps = pcie_get_mps(bridge);
1995
1996 if (mps == p_mps)
1997 return;
1998
1999 if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
2000 pci_warn(dev, "Max Payload Size %d, but upstream %s set to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
2001 mps, pci_name(bridge), p_mps);
2002 return;
2003 }
2004
2005 /*
2006 * Fancier MPS configuration is done later by
2007 * pcie_bus_configure_settings()
2008 */
2009 if (pcie_bus_config != PCIE_BUS_DEFAULT)
2010 return;
2011
2012 mpss = 128 << dev->pcie_mpss;
2013 if (mpss < p_mps && pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT) {
2014 pcie_set_mps(bridge, mpss);
2015 pci_info(dev, "Upstream bridge's Max Payload Size set to %d (was %d, max %d)\n",
2016 mpss, p_mps, 128 << bridge->pcie_mpss);
2017 p_mps = pcie_get_mps(bridge);
2018 }
2019
2020 rc = pcie_set_mps(dev, p_mps);
2021 if (rc) {
2022 pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
2023 p_mps);
2024 return;
2025 }
2026
2027 pci_info(dev, "Max Payload Size set to %d (was %d, max %d)\n",
2028 p_mps, mps, mpss);
2029}
2030
2031int pci_configure_extended_tags(struct pci_dev *dev, void *ign)
2032{
2033 struct pci_host_bridge *host;
2034 u32 cap;
2035 u16 ctl;
2036 int ret;
2037
2038 if (!pci_is_pcie(dev))
2039 return 0;
2040
2041 ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap);
2042 if (ret)
2043 return 0;
2044
2045 if (!(cap & PCI_EXP_DEVCAP_EXT_TAG))
2046 return 0;
2047
2048 ret = pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
2049 if (ret)
2050 return 0;
2051
2052 host = pci_find_host_bridge(dev->bus);
2053 if (!host)
2054 return 0;
2055
2056 /*
2057 * If some device in the hierarchy doesn't handle Extended Tags
2058 * correctly, make sure they're disabled.
2059 */
2060 if (host->no_ext_tags) {
2061 if (ctl & PCI_EXP_DEVCTL_EXT_TAG) {
2062 pci_info(dev, "disabling Extended Tags\n");
2063 pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
2064 PCI_EXP_DEVCTL_EXT_TAG);
2065 }
2066 return 0;
2067 }
2068
2069 if (!(ctl & PCI_EXP_DEVCTL_EXT_TAG)) {
2070 pci_info(dev, "enabling Extended Tags\n");
2071 pcie_capability_set_word(dev, PCI_EXP_DEVCTL,
2072 PCI_EXP_DEVCTL_EXT_TAG);
2073 }
2074 return 0;
2075}
2076
2077/**
2078 * pcie_relaxed_ordering_enabled - Probe for PCIe relaxed ordering enable
2079 * @dev: PCI device to query
2080 *
2081 * Returns true if the device has enabled relaxed ordering attribute.
2082 */
2083bool pcie_relaxed_ordering_enabled(struct pci_dev *dev)
2084{
2085 u16 v;
2086
2087 pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &v);
2088
2089 return !!(v & PCI_EXP_DEVCTL_RELAX_EN);
2090}
2091EXPORT_SYMBOL(pcie_relaxed_ordering_enabled);
2092
2093static void pci_configure_relaxed_ordering(struct pci_dev *dev)
2094{
2095 struct pci_dev *root;
2096
2097 /* PCI_EXP_DEVICE_RELAX_EN is RsvdP in VFs */
2098 if (dev->is_virtfn)
2099 return;
2100
2101 if (!pcie_relaxed_ordering_enabled(dev))
2102 return;
2103
2104 /*
2105 * For now, we only deal with Relaxed Ordering issues with Root
2106 * Ports. Peer-to-Peer DMA is another can of worms.
2107 */
2108 root = pcie_find_root_port(dev);
2109 if (!root)
2110 return;
2111
2112 if (root->dev_flags & PCI_DEV_FLAGS_NO_RELAXED_ORDERING) {
2113 pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
2114 PCI_EXP_DEVCTL_RELAX_EN);
2115 pci_info(dev, "Relaxed Ordering disabled because the Root Port didn't support it\n");
2116 }
2117}
2118
2119static void pci_configure_ltr(struct pci_dev *dev)
2120{
2121#ifdef CONFIG_PCIEASPM
2122 struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
2123 struct pci_dev *bridge;
2124 u32 cap, ctl;
2125
2126 if (!pci_is_pcie(dev))
2127 return;
2128
2129 /* Read L1 PM substate capabilities */
2130 dev->l1ss = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_L1SS);
2131
2132 pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
2133 if (!(cap & PCI_EXP_DEVCAP2_LTR))
2134 return;
2135
2136 pcie_capability_read_dword(dev, PCI_EXP_DEVCTL2, &ctl);
2137 if (ctl & PCI_EXP_DEVCTL2_LTR_EN) {
2138 if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
2139 dev->ltr_path = 1;
2140 return;
2141 }
2142
2143 bridge = pci_upstream_bridge(dev);
2144 if (bridge && bridge->ltr_path)
2145 dev->ltr_path = 1;
2146
2147 return;
2148 }
2149
2150 if (!host->native_ltr)
2151 return;
2152
2153 /*
2154 * Software must not enable LTR in an Endpoint unless the Root
2155 * Complex and all intermediate Switches indicate support for LTR.
2156 * PCIe r4.0, sec 6.18.
2157 */
2158 if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT ||
2159 ((bridge = pci_upstream_bridge(dev)) &&
2160 bridge->ltr_path)) {
2161 pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
2162 PCI_EXP_DEVCTL2_LTR_EN);
2163 dev->ltr_path = 1;
2164 }
2165#endif
2166}
2167
2168static void pci_configure_eetlp_prefix(struct pci_dev *dev)
2169{
2170#ifdef CONFIG_PCI_PASID
2171 struct pci_dev *bridge;
2172 int pcie_type;
2173 u32 cap;
2174
2175 if (!pci_is_pcie(dev))
2176 return;
2177
2178 pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
2179 if (!(cap & PCI_EXP_DEVCAP2_EE_PREFIX))
2180 return;
2181
2182 pcie_type = pci_pcie_type(dev);
2183 if (pcie_type == PCI_EXP_TYPE_ROOT_PORT ||
2184 pcie_type == PCI_EXP_TYPE_RC_END)
2185 dev->eetlp_prefix_path = 1;
2186 else {
2187 bridge = pci_upstream_bridge(dev);
2188 if (bridge && bridge->eetlp_prefix_path)
2189 dev->eetlp_prefix_path = 1;
2190 }
2191#endif
2192}
2193
2194static void pci_configure_serr(struct pci_dev *dev)
2195{
2196 u16 control;
2197
2198 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
2199
2200 /*
2201 * A bridge will not forward ERR_ messages coming from an
2202 * endpoint unless SERR# forwarding is enabled.
2203 */
2204 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &control);
2205 if (!(control & PCI_BRIDGE_CTL_SERR)) {
2206 control |= PCI_BRIDGE_CTL_SERR;
2207 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, control);
2208 }
2209 }
2210}
2211
2212static void pci_configure_device(struct pci_dev *dev)
2213{
2214 pci_configure_mps(dev);
2215 pci_configure_extended_tags(dev, NULL);
2216 pci_configure_relaxed_ordering(dev);
2217 pci_configure_ltr(dev);
2218 pci_configure_eetlp_prefix(dev);
2219 pci_configure_serr(dev);
2220
2221 pci_acpi_program_hp_params(dev);
2222}
2223
2224static void pci_release_capabilities(struct pci_dev *dev)
2225{
2226 pci_aer_exit(dev);
2227 pci_rcec_exit(dev);
2228 pci_vpd_release(dev);
2229 pci_iov_release(dev);
2230 pci_free_cap_save_buffers(dev);
2231}
2232
2233/**
2234 * pci_release_dev - Free a PCI device structure when all users of it are
2235 * finished
2236 * @dev: device that's been disconnected
2237 *
2238 * Will be called only by the device core when all users of this PCI device are
2239 * done.
2240 */
2241static void pci_release_dev(struct device *dev)
2242{
2243 struct pci_dev *pci_dev;
2244
2245 pci_dev = to_pci_dev(dev);
2246 pci_release_capabilities(pci_dev);
2247 pci_release_of_node(pci_dev);
2248 pcibios_release_device(pci_dev);
2249 pci_bus_put(pci_dev->bus);
2250 kfree(pci_dev->driver_override);
2251 bitmap_free(pci_dev->dma_alias_mask);
2252 dev_dbg(dev, "device released\n");
2253 kfree(pci_dev);
2254}
2255
2256struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
2257{
2258 struct pci_dev *dev;
2259
2260 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
2261 if (!dev)
2262 return NULL;
2263
2264 INIT_LIST_HEAD(&dev->bus_list);
2265 dev->dev.type = &pci_dev_type;
2266 dev->bus = pci_bus_get(bus);
2267
2268 return dev;
2269}
2270EXPORT_SYMBOL(pci_alloc_dev);
2271
2272static bool pci_bus_crs_vendor_id(u32 l)
2273{
2274 return (l & 0xffff) == 0x0001;
2275}
2276
2277static bool pci_bus_wait_crs(struct pci_bus *bus, int devfn, u32 *l,
2278 int timeout)
2279{
2280 int delay = 1;
2281
2282 if (!pci_bus_crs_vendor_id(*l))
2283 return true; /* not a CRS completion */
2284
2285 if (!timeout)
2286 return false; /* CRS, but caller doesn't want to wait */
2287
2288 /*
2289 * We got the reserved Vendor ID that indicates a completion with
2290 * Configuration Request Retry Status (CRS). Retry until we get a
2291 * valid Vendor ID or we time out.
2292 */
2293 while (pci_bus_crs_vendor_id(*l)) {
2294 if (delay > timeout) {
2295 pr_warn("pci %04x:%02x:%02x.%d: not ready after %dms; giving up\n",
2296 pci_domain_nr(bus), bus->number,
2297 PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2298
2299 return false;
2300 }
2301 if (delay >= 1000)
2302 pr_info("pci %04x:%02x:%02x.%d: not ready after %dms; waiting\n",
2303 pci_domain_nr(bus), bus->number,
2304 PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2305
2306 msleep(delay);
2307 delay *= 2;
2308
2309 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
2310 return false;
2311 }
2312
2313 if (delay >= 1000)
2314 pr_info("pci %04x:%02x:%02x.%d: ready after %dms\n",
2315 pci_domain_nr(bus), bus->number,
2316 PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2317
2318 return true;
2319}
2320
2321bool pci_bus_generic_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
2322 int timeout)
2323{
2324 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
2325 return false;
2326
2327 /* Some broken boards return 0 or ~0 if a slot is empty: */
2328 if (*l == 0xffffffff || *l == 0x00000000 ||
2329 *l == 0x0000ffff || *l == 0xffff0000)
2330 return false;
2331
2332 if (pci_bus_crs_vendor_id(*l))
2333 return pci_bus_wait_crs(bus, devfn, l, timeout);
2334
2335 return true;
2336}
2337
2338bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
2339 int timeout)
2340{
2341#ifdef CONFIG_PCI_QUIRKS
2342 struct pci_dev *bridge = bus->self;
2343
2344 /*
2345 * Certain IDT switches have an issue where they improperly trigger
2346 * ACS Source Validation errors on completions for config reads.
2347 */
2348 if (bridge && bridge->vendor == PCI_VENDOR_ID_IDT &&
2349 bridge->device == 0x80b5)
2350 return pci_idt_bus_quirk(bus, devfn, l, timeout);
2351#endif
2352
2353 return pci_bus_generic_read_dev_vendor_id(bus, devfn, l, timeout);
2354}
2355EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
2356
2357/*
2358 * Read the config data for a PCI device, sanity-check it,
2359 * and fill in the dev structure.
2360 */
2361static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
2362{
2363 struct pci_dev *dev;
2364 u32 l;
2365
2366 if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
2367 return NULL;
2368
2369 dev = pci_alloc_dev(bus);
2370 if (!dev)
2371 return NULL;
2372
2373 dev->devfn = devfn;
2374 dev->vendor = l & 0xffff;
2375 dev->device = (l >> 16) & 0xffff;
2376
2377 pci_set_of_node(dev);
2378
2379 if (pci_setup_device(dev)) {
2380 pci_release_of_node(dev);
2381 pci_bus_put(dev->bus);
2382 kfree(dev);
2383 return NULL;
2384 }
2385
2386 return dev;
2387}
2388
2389void pcie_report_downtraining(struct pci_dev *dev)
2390{
2391 if (!pci_is_pcie(dev))
2392 return;
2393
2394 /* Look from the device up to avoid downstream ports with no devices */
2395 if ((pci_pcie_type(dev) != PCI_EXP_TYPE_ENDPOINT) &&
2396 (pci_pcie_type(dev) != PCI_EXP_TYPE_LEG_END) &&
2397 (pci_pcie_type(dev) != PCI_EXP_TYPE_UPSTREAM))
2398 return;
2399
2400 /* Multi-function PCIe devices share the same link/status */
2401 if (PCI_FUNC(dev->devfn) != 0 || dev->is_virtfn)
2402 return;
2403
2404 /* Print link status only if the device is constrained by the fabric */
2405 __pcie_print_link_status(dev, false);
2406}
2407
2408static void pci_init_capabilities(struct pci_dev *dev)
2409{
2410 pci_ea_init(dev); /* Enhanced Allocation */
2411 pci_msi_init(dev); /* Disable MSI */
2412 pci_msix_init(dev); /* Disable MSI-X */
2413
2414 /* Buffers for saving PCIe and PCI-X capabilities */
2415 pci_allocate_cap_save_buffers(dev);
2416
2417 pci_pm_init(dev); /* Power Management */
2418 pci_vpd_init(dev); /* Vital Product Data */
2419 pci_configure_ari(dev); /* Alternative Routing-ID Forwarding */
2420 pci_iov_init(dev); /* Single Root I/O Virtualization */
2421 pci_ats_init(dev); /* Address Translation Services */
2422 pci_pri_init(dev); /* Page Request Interface */
2423 pci_pasid_init(dev); /* Process Address Space ID */
2424 pci_acs_init(dev); /* Access Control Services */
2425 pci_ptm_init(dev); /* Precision Time Measurement */
2426 pci_aer_init(dev); /* Advanced Error Reporting */
2427 pci_dpc_init(dev); /* Downstream Port Containment */
2428 pci_rcec_init(dev); /* Root Complex Event Collector */
2429
2430 pcie_report_downtraining(dev);
2431
2432 if (pci_probe_reset_function(dev) == 0)
2433 dev->reset_fn = 1;
2434}
2435
2436/*
2437 * This is the equivalent of pci_host_bridge_msi_domain() that acts on
2438 * devices. Firmware interfaces that can select the MSI domain on a
2439 * per-device basis should be called from here.
2440 */
2441static struct irq_domain *pci_dev_msi_domain(struct pci_dev *dev)
2442{
2443 struct irq_domain *d;
2444
2445 /*
2446 * If a domain has been set through the pcibios_add_device()
2447 * callback, then this is the one (platform code knows best).
2448 */
2449 d = dev_get_msi_domain(&dev->dev);
2450 if (d)
2451 return d;
2452
2453 /*
2454 * Let's see if we have a firmware interface able to provide
2455 * the domain.
2456 */
2457 d = pci_msi_get_device_domain(dev);
2458 if (d)
2459 return d;
2460
2461 return NULL;
2462}
2463
2464static void pci_set_msi_domain(struct pci_dev *dev)
2465{
2466 struct irq_domain *d;
2467
2468 /*
2469 * If the platform or firmware interfaces cannot supply a
2470 * device-specific MSI domain, then inherit the default domain
2471 * from the host bridge itself.
2472 */
2473 d = pci_dev_msi_domain(dev);
2474 if (!d)
2475 d = dev_get_msi_domain(&dev->bus->dev);
2476
2477 dev_set_msi_domain(&dev->dev, d);
2478}
2479
2480void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
2481{
2482 int ret;
2483
2484 pci_configure_device(dev);
2485
2486 device_initialize(&dev->dev);
2487 dev->dev.release = pci_release_dev;
2488
2489 set_dev_node(&dev->dev, pcibus_to_node(bus));
2490 dev->dev.dma_mask = &dev->dma_mask;
2491 dev->dev.dma_parms = &dev->dma_parms;
2492 dev->dev.coherent_dma_mask = 0xffffffffull;
2493
2494 dma_set_max_seg_size(&dev->dev, 65536);
2495 dma_set_seg_boundary(&dev->dev, 0xffffffff);
2496
2497 /* Fix up broken headers */
2498 pci_fixup_device(pci_fixup_header, dev);
2499
2500 pci_reassigndev_resource_alignment(dev);
2501
2502 dev->state_saved = false;
2503
2504 pci_init_capabilities(dev);
2505
2506 /*
2507 * Add the device to our list of discovered devices
2508 * and the bus list for fixup functions, etc.
2509 */
2510 down_write(&pci_bus_sem);
2511 list_add_tail(&dev->bus_list, &bus->devices);
2512 up_write(&pci_bus_sem);
2513
2514 ret = pcibios_add_device(dev);
2515 WARN_ON(ret < 0);
2516
2517 /* Set up MSI IRQ domain */
2518 pci_set_msi_domain(dev);
2519
2520 /* Notifier could use PCI capabilities */
2521 dev->match_driver = false;
2522 ret = device_add(&dev->dev);
2523 WARN_ON(ret < 0);
2524}
2525
2526struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn)
2527{
2528 struct pci_dev *dev;
2529
2530 dev = pci_get_slot(bus, devfn);
2531 if (dev) {
2532 pci_dev_put(dev);
2533 return dev;
2534 }
2535
2536 dev = pci_scan_device(bus, devfn);
2537 if (!dev)
2538 return NULL;
2539
2540 pci_device_add(dev, bus);
2541
2542 return dev;
2543}
2544EXPORT_SYMBOL(pci_scan_single_device);
2545
2546static unsigned next_fn(struct pci_bus *bus, struct pci_dev *dev, unsigned fn)
2547{
2548 int pos;
2549 u16 cap = 0;
2550 unsigned next_fn;
2551
2552 if (pci_ari_enabled(bus)) {
2553 if (!dev)
2554 return 0;
2555 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
2556 if (!pos)
2557 return 0;
2558
2559 pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap);
2560 next_fn = PCI_ARI_CAP_NFN(cap);
2561 if (next_fn <= fn)
2562 return 0; /* protect against malformed list */
2563
2564 return next_fn;
2565 }
2566
2567 /* dev may be NULL for non-contiguous multifunction devices */
2568 if (!dev || dev->multifunction)
2569 return (fn + 1) % 8;
2570
2571 return 0;
2572}
2573
2574static int only_one_child(struct pci_bus *bus)
2575{
2576 struct pci_dev *bridge = bus->self;
2577
2578 /*
2579 * Systems with unusual topologies set PCI_SCAN_ALL_PCIE_DEVS so
2580 * we scan for all possible devices, not just Device 0.
2581 */
2582 if (pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
2583 return 0;
2584
2585 /*
2586 * A PCIe Downstream Port normally leads to a Link with only Device
2587 * 0 on it (PCIe spec r3.1, sec 7.3.1). As an optimization, scan
2588 * only for Device 0 in that situation.
2589 */
2590 if (bridge && pci_is_pcie(bridge) && pcie_downstream_port(bridge))
2591 return 1;
2592
2593 return 0;
2594}
2595
2596/**
2597 * pci_scan_slot - Scan a PCI slot on a bus for devices
2598 * @bus: PCI bus to scan
2599 * @devfn: slot number to scan (must have zero function)
2600 *
2601 * Scan a PCI slot on the specified PCI bus for devices, adding
2602 * discovered devices to the @bus->devices list. New devices
2603 * will not have is_added set.
2604 *
2605 * Returns the number of new devices found.
2606 */
2607int pci_scan_slot(struct pci_bus *bus, int devfn)
2608{
2609 unsigned fn, nr = 0;
2610 struct pci_dev *dev;
2611
2612 if (only_one_child(bus) && (devfn > 0))
2613 return 0; /* Already scanned the entire slot */
2614
2615 dev = pci_scan_single_device(bus, devfn);
2616 if (!dev)
2617 return 0;
2618 if (!pci_dev_is_added(dev))
2619 nr++;
2620
2621 for (fn = next_fn(bus, dev, 0); fn > 0; fn = next_fn(bus, dev, fn)) {
2622 dev = pci_scan_single_device(bus, devfn + fn);
2623 if (dev) {
2624 if (!pci_dev_is_added(dev))
2625 nr++;
2626 dev->multifunction = 1;
2627 }
2628 }
2629
2630 /* Only one slot has PCIe device */
2631 if (bus->self && nr)
2632 pcie_aspm_init_link_state(bus->self);
2633
2634 return nr;
2635}
2636EXPORT_SYMBOL(pci_scan_slot);
2637
2638static int pcie_find_smpss(struct pci_dev *dev, void *data)
2639{
2640 u8 *smpss = data;
2641
2642 if (!pci_is_pcie(dev))
2643 return 0;
2644
2645 /*
2646 * We don't have a way to change MPS settings on devices that have
2647 * drivers attached. A hot-added device might support only the minimum
2648 * MPS setting (MPS=128). Therefore, if the fabric contains a bridge
2649 * where devices may be hot-added, we limit the fabric MPS to 128 so
2650 * hot-added devices will work correctly.
2651 *
2652 * However, if we hot-add a device to a slot directly below a Root
2653 * Port, it's impossible for there to be other existing devices below
2654 * the port. We don't limit the MPS in this case because we can
2655 * reconfigure MPS on both the Root Port and the hot-added device,
2656 * and there are no other devices involved.
2657 *
2658 * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
2659 */
2660 if (dev->is_hotplug_bridge &&
2661 pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
2662 *smpss = 0;
2663
2664 if (*smpss > dev->pcie_mpss)
2665 *smpss = dev->pcie_mpss;
2666
2667 return 0;
2668}
2669
2670static void pcie_write_mps(struct pci_dev *dev, int mps)
2671{
2672 int rc;
2673
2674 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
2675 mps = 128 << dev->pcie_mpss;
2676
2677 if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
2678 dev->bus->self)
2679
2680 /*
2681 * For "Performance", the assumption is made that
2682 * downstream communication will never be larger than
2683 * the MRRS. So, the MPS only needs to be configured
2684 * for the upstream communication. This being the case,
2685 * walk from the top down and set the MPS of the child
2686 * to that of the parent bus.
2687 *
2688 * Configure the device MPS with the smaller of the
2689 * device MPSS or the bridge MPS (which is assumed to be
2690 * properly configured at this point to the largest
2691 * allowable MPS based on its parent bus).
2692 */
2693 mps = min(mps, pcie_get_mps(dev->bus->self));
2694 }
2695
2696 rc = pcie_set_mps(dev, mps);
2697 if (rc)
2698 pci_err(dev, "Failed attempting to set the MPS\n");
2699}
2700
2701static void pcie_write_mrrs(struct pci_dev *dev)
2702{
2703 int rc, mrrs;
2704
2705 /*
2706 * In the "safe" case, do not configure the MRRS. There appear to be
2707 * issues with setting MRRS to 0 on a number of devices.
2708 */
2709 if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
2710 return;
2711
2712 /*
2713 * For max performance, the MRRS must be set to the largest supported
2714 * value. However, it cannot be configured larger than the MPS the
2715 * device or the bus can support. This should already be properly
2716 * configured by a prior call to pcie_write_mps().
2717 */
2718 mrrs = pcie_get_mps(dev);
2719
2720 /*
2721 * MRRS is a R/W register. Invalid values can be written, but a
2722 * subsequent read will verify if the value is acceptable or not.
2723 * If the MRRS value provided is not acceptable (e.g., too large),
2724 * shrink the value until it is acceptable to the HW.
2725 */
2726 while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
2727 rc = pcie_set_readrq(dev, mrrs);
2728 if (!rc)
2729 break;
2730
2731 pci_warn(dev, "Failed attempting to set the MRRS\n");
2732 mrrs /= 2;
2733 }
2734
2735 if (mrrs < 128)
2736 pci_err(dev, "MRRS was unable to be configured with a safe value. If problems are experienced, try running with pci=pcie_bus_safe\n");
2737}
2738
2739static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
2740{
2741 int mps, orig_mps;
2742
2743 if (!pci_is_pcie(dev))
2744 return 0;
2745
2746 if (pcie_bus_config == PCIE_BUS_TUNE_OFF ||
2747 pcie_bus_config == PCIE_BUS_DEFAULT)
2748 return 0;
2749
2750 mps = 128 << *(u8 *)data;
2751 orig_mps = pcie_get_mps(dev);
2752
2753 pcie_write_mps(dev, mps);
2754 pcie_write_mrrs(dev);
2755
2756 pci_info(dev, "Max Payload Size set to %4d/%4d (was %4d), Max Read Rq %4d\n",
2757 pcie_get_mps(dev), 128 << dev->pcie_mpss,
2758 orig_mps, pcie_get_readrq(dev));
2759
2760 return 0;
2761}
2762
2763/*
2764 * pcie_bus_configure_settings() requires that pci_walk_bus work in a top-down,
2765 * parents then children fashion. If this changes, then this code will not
2766 * work as designed.
2767 */
2768void pcie_bus_configure_settings(struct pci_bus *bus)
2769{
2770 u8 smpss = 0;
2771
2772 if (!bus->self)
2773 return;
2774
2775 if (!pci_is_pcie(bus->self))
2776 return;
2777
2778 /*
2779 * FIXME - Peer to peer DMA is possible, though the endpoint would need
2780 * to be aware of the MPS of the destination. To work around this,
2781 * simply force the MPS of the entire system to the smallest possible.
2782 */
2783 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
2784 smpss = 0;
2785
2786 if (pcie_bus_config == PCIE_BUS_SAFE) {
2787 smpss = bus->self->pcie_mpss;
2788
2789 pcie_find_smpss(bus->self, &smpss);
2790 pci_walk_bus(bus, pcie_find_smpss, &smpss);
2791 }
2792
2793 pcie_bus_configure_set(bus->self, &smpss);
2794 pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
2795}
2796EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
2797
2798/*
2799 * Called after each bus is probed, but before its children are examined. This
2800 * is marked as __weak because multiple architectures define it.
2801 */
2802void __weak pcibios_fixup_bus(struct pci_bus *bus)
2803{
2804 /* nothing to do, expected to be removed in the future */
2805}
2806
2807/**
2808 * pci_scan_child_bus_extend() - Scan devices below a bus
2809 * @bus: Bus to scan for devices
2810 * @available_buses: Total number of buses available (%0 does not try to
2811 * extend beyond the minimal)
2812 *
2813 * Scans devices below @bus including subordinate buses. Returns new
2814 * subordinate number including all the found devices. Passing
2815 * @available_buses causes the remaining bus space to be distributed
2816 * equally between hotplug-capable bridges to allow future extension of the
2817 * hierarchy.
2818 */
2819static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
2820 unsigned int available_buses)
2821{
2822 unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0;
2823 unsigned int start = bus->busn_res.start;
2824 unsigned int devfn, fn, cmax, max = start;
2825 struct pci_dev *dev;
2826 int nr_devs;
2827
2828 dev_dbg(&bus->dev, "scanning bus\n");
2829
2830 /* Go find them, Rover! */
2831 for (devfn = 0; devfn < 256; devfn += 8) {
2832 nr_devs = pci_scan_slot(bus, devfn);
2833
2834 /*
2835 * The Jailhouse hypervisor may pass individual functions of a
2836 * multi-function device to a guest without passing function 0.
2837 * Look for them as well.
2838 */
2839 if (jailhouse_paravirt() && nr_devs == 0) {
2840 for (fn = 1; fn < 8; fn++) {
2841 dev = pci_scan_single_device(bus, devfn + fn);
2842 if (dev)
2843 dev->multifunction = 1;
2844 }
2845 }
2846 }
2847
2848 /* Reserve buses for SR-IOV capability */
2849 used_buses = pci_iov_bus_range(bus);
2850 max += used_buses;
2851
2852 /*
2853 * After performing arch-dependent fixup of the bus, look behind
2854 * all PCI-to-PCI bridges on this bus.
2855 */
2856 if (!bus->is_added) {
2857 dev_dbg(&bus->dev, "fixups for bus\n");
2858 pcibios_fixup_bus(bus);
2859 bus->is_added = 1;
2860 }
2861
2862 /*
2863 * Calculate how many hotplug bridges and normal bridges there
2864 * are on this bus. We will distribute the additional available
2865 * buses between hotplug bridges.
2866 */
2867 for_each_pci_bridge(dev, bus) {
2868 if (dev->is_hotplug_bridge)
2869 hotplug_bridges++;
2870 else
2871 normal_bridges++;
2872 }
2873
2874 /*
2875 * Scan bridges that are already configured. We don't touch them
2876 * unless they are misconfigured (which will be done in the second
2877 * scan below).
2878 */
2879 for_each_pci_bridge(dev, bus) {
2880 cmax = max;
2881 max = pci_scan_bridge_extend(bus, dev, max, 0, 0);
2882
2883 /*
2884 * Reserve one bus for each bridge now to avoid extending
2885 * hotplug bridges too much during the second scan below.
2886 */
2887 used_buses++;
2888 if (cmax - max > 1)
2889 used_buses += cmax - max - 1;
2890 }
2891
2892 /* Scan bridges that need to be reconfigured */
2893 for_each_pci_bridge(dev, bus) {
2894 unsigned int buses = 0;
2895
2896 if (!hotplug_bridges && normal_bridges == 1) {
2897
2898 /*
2899 * There is only one bridge on the bus (upstream
2900 * port) so it gets all available buses which it
2901 * can then distribute to the possible hotplug
2902 * bridges below.
2903 */
2904 buses = available_buses;
2905 } else if (dev->is_hotplug_bridge) {
2906
2907 /*
2908 * Distribute the extra buses between hotplug
2909 * bridges if any.
2910 */
2911 buses = available_buses / hotplug_bridges;
2912 buses = min(buses, available_buses - used_buses + 1);
2913 }
2914
2915 cmax = max;
2916 max = pci_scan_bridge_extend(bus, dev, cmax, buses, 1);
2917 /* One bus is already accounted so don't add it again */
2918 if (max - cmax > 1)
2919 used_buses += max - cmax - 1;
2920 }
2921
2922 /*
2923 * Make sure a hotplug bridge has at least the minimum requested
2924 * number of buses but allow it to grow up to the maximum available
2925 * bus number of there is room.
2926 */
2927 if (bus->self && bus->self->is_hotplug_bridge) {
2928 used_buses = max_t(unsigned int, available_buses,
2929 pci_hotplug_bus_size - 1);
2930 if (max - start < used_buses) {
2931 max = start + used_buses;
2932
2933 /* Do not allocate more buses than we have room left */
2934 if (max > bus->busn_res.end)
2935 max = bus->busn_res.end;
2936
2937 dev_dbg(&bus->dev, "%pR extended by %#02x\n",
2938 &bus->busn_res, max - start);
2939 }
2940 }
2941
2942 /*
2943 * We've scanned the bus and so we know all about what's on
2944 * the other side of any bridges that may be on this bus plus
2945 * any devices.
2946 *
2947 * Return how far we've got finding sub-buses.
2948 */
2949 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
2950 return max;
2951}
2952
2953/**
2954 * pci_scan_child_bus() - Scan devices below a bus
2955 * @bus: Bus to scan for devices
2956 *
2957 * Scans devices below @bus including subordinate buses. Returns new
2958 * subordinate number including all the found devices.
2959 */
2960unsigned int pci_scan_child_bus(struct pci_bus *bus)
2961{
2962 return pci_scan_child_bus_extend(bus, 0);
2963}
2964EXPORT_SYMBOL_GPL(pci_scan_child_bus);
2965
2966/**
2967 * pcibios_root_bridge_prepare - Platform-specific host bridge setup
2968 * @bridge: Host bridge to set up
2969 *
2970 * Default empty implementation. Replace with an architecture-specific setup
2971 * routine, if necessary.
2972 */
2973int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
2974{
2975 return 0;
2976}
2977
2978void __weak pcibios_add_bus(struct pci_bus *bus)
2979{
2980}
2981
2982void __weak pcibios_remove_bus(struct pci_bus *bus)
2983{
2984}
2985
2986struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
2987 struct pci_ops *ops, void *sysdata, struct list_head *resources)
2988{
2989 int error;
2990 struct pci_host_bridge *bridge;
2991
2992 bridge = pci_alloc_host_bridge(0);
2993 if (!bridge)
2994 return NULL;
2995
2996 bridge->dev.parent = parent;
2997
2998 list_splice_init(resources, &bridge->windows);
2999 bridge->sysdata = sysdata;
3000 bridge->busnr = bus;
3001 bridge->ops = ops;
3002
3003 error = pci_register_host_bridge(bridge);
3004 if (error < 0)
3005 goto err_out;
3006
3007 return bridge->bus;
3008
3009err_out:
3010 put_device(&bridge->dev);
3011 return NULL;
3012}
3013EXPORT_SYMBOL_GPL(pci_create_root_bus);
3014
3015int pci_host_probe(struct pci_host_bridge *bridge)
3016{
3017 struct pci_bus *bus, *child;
3018 int ret;
3019
3020 ret = pci_scan_root_bus_bridge(bridge);
3021 if (ret < 0) {
3022 dev_err(bridge->dev.parent, "Scanning root bridge failed");
3023 return ret;
3024 }
3025
3026 bus = bridge->bus;
3027
3028 /*
3029 * We insert PCI resources into the iomem_resource and
3030 * ioport_resource trees in either pci_bus_claim_resources()
3031 * or pci_bus_assign_resources().
3032 */
3033 if (pci_has_flag(PCI_PROBE_ONLY)) {
3034 pci_bus_claim_resources(bus);
3035 } else {
3036 pci_bus_size_bridges(bus);
3037 pci_bus_assign_resources(bus);
3038
3039 list_for_each_entry(child, &bus->children, node)
3040 pcie_bus_configure_settings(child);
3041 }
3042
3043 pci_bus_add_devices(bus);
3044 return 0;
3045}
3046EXPORT_SYMBOL_GPL(pci_host_probe);
3047
3048int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
3049{
3050 struct resource *res = &b->busn_res;
3051 struct resource *parent_res, *conflict;
3052
3053 res->start = bus;
3054 res->end = bus_max;
3055 res->flags = IORESOURCE_BUS;
3056
3057 if (!pci_is_root_bus(b))
3058 parent_res = &b->parent->busn_res;
3059 else {
3060 parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
3061 res->flags |= IORESOURCE_PCI_FIXED;
3062 }
3063
3064 conflict = request_resource_conflict(parent_res, res);
3065
3066 if (conflict)
3067 dev_info(&b->dev,
3068 "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
3069 res, pci_is_root_bus(b) ? "domain " : "",
3070 parent_res, conflict->name, conflict);
3071
3072 return conflict == NULL;
3073}
3074
3075int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
3076{
3077 struct resource *res = &b->busn_res;
3078 struct resource old_res = *res;
3079 resource_size_t size;
3080 int ret;
3081
3082 if (res->start > bus_max)
3083 return -EINVAL;
3084
3085 size = bus_max - res->start + 1;
3086 ret = adjust_resource(res, res->start, size);
3087 dev_info(&b->dev, "busn_res: %pR end %s updated to %02x\n",
3088 &old_res, ret ? "can not be" : "is", bus_max);
3089
3090 if (!ret && !res->parent)
3091 pci_bus_insert_busn_res(b, res->start, res->end);
3092
3093 return ret;
3094}
3095
3096void pci_bus_release_busn_res(struct pci_bus *b)
3097{
3098 struct resource *res = &b->busn_res;
3099 int ret;
3100
3101 if (!res->flags || !res->parent)
3102 return;
3103
3104 ret = release_resource(res);
3105 dev_info(&b->dev, "busn_res: %pR %s released\n",
3106 res, ret ? "can not be" : "is");
3107}
3108
3109int pci_scan_root_bus_bridge(struct pci_host_bridge *bridge)
3110{
3111 struct resource_entry *window;
3112 bool found = false;
3113 struct pci_bus *b;
3114 int max, bus, ret;
3115
3116 if (!bridge)
3117 return -EINVAL;
3118
3119 resource_list_for_each_entry(window, &bridge->windows)
3120 if (window->res->flags & IORESOURCE_BUS) {
3121 bridge->busnr = window->res->start;
3122 found = true;
3123 break;
3124 }
3125
3126 ret = pci_register_host_bridge(bridge);
3127 if (ret < 0)
3128 return ret;
3129
3130 b = bridge->bus;
3131 bus = bridge->busnr;
3132
3133 if (!found) {
3134 dev_info(&b->dev,
3135 "No busn resource found for root bus, will use [bus %02x-ff]\n",
3136 bus);
3137 pci_bus_insert_busn_res(b, bus, 255);
3138 }
3139
3140 max = pci_scan_child_bus(b);
3141
3142 if (!found)
3143 pci_bus_update_busn_res_end(b, max);
3144
3145 return 0;
3146}
3147EXPORT_SYMBOL(pci_scan_root_bus_bridge);
3148
3149struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
3150 struct pci_ops *ops, void *sysdata, struct list_head *resources)
3151{
3152 struct resource_entry *window;
3153 bool found = false;
3154 struct pci_bus *b;
3155 int max;
3156
3157 resource_list_for_each_entry(window, resources)
3158 if (window->res->flags & IORESOURCE_BUS) {
3159 found = true;
3160 break;
3161 }
3162
3163 b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
3164 if (!b)
3165 return NULL;
3166
3167 if (!found) {
3168 dev_info(&b->dev,
3169 "No busn resource found for root bus, will use [bus %02x-ff]\n",
3170 bus);
3171 pci_bus_insert_busn_res(b, bus, 255);
3172 }
3173
3174 max = pci_scan_child_bus(b);
3175
3176 if (!found)
3177 pci_bus_update_busn_res_end(b, max);
3178
3179 return b;
3180}
3181EXPORT_SYMBOL(pci_scan_root_bus);
3182
3183struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
3184 void *sysdata)
3185{
3186 LIST_HEAD(resources);
3187 struct pci_bus *b;
3188
3189 pci_add_resource(&resources, &ioport_resource);
3190 pci_add_resource(&resources, &iomem_resource);
3191 pci_add_resource(&resources, &busn_resource);
3192 b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
3193 if (b) {
3194 pci_scan_child_bus(b);
3195 } else {
3196 pci_free_resource_list(&resources);
3197 }
3198 return b;
3199}
3200EXPORT_SYMBOL(pci_scan_bus);
3201
3202/**
3203 * pci_rescan_bus_bridge_resize - Scan a PCI bus for devices
3204 * @bridge: PCI bridge for the bus to scan
3205 *
3206 * Scan a PCI bus and child buses for new devices, add them,
3207 * and enable them, resizing bridge mmio/io resource if necessary
3208 * and possible. The caller must ensure the child devices are already
3209 * removed for resizing to occur.
3210 *
3211 * Returns the max number of subordinate bus discovered.
3212 */
3213unsigned int pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
3214{
3215 unsigned int max;
3216 struct pci_bus *bus = bridge->subordinate;
3217
3218 max = pci_scan_child_bus(bus);
3219
3220 pci_assign_unassigned_bridge_resources(bridge);
3221
3222 pci_bus_add_devices(bus);
3223
3224 return max;
3225}
3226
3227/**
3228 * pci_rescan_bus - Scan a PCI bus for devices
3229 * @bus: PCI bus to scan
3230 *
3231 * Scan a PCI bus and child buses for new devices, add them,
3232 * and enable them.
3233 *
3234 * Returns the max number of subordinate bus discovered.
3235 */
3236unsigned int pci_rescan_bus(struct pci_bus *bus)
3237{
3238 unsigned int max;
3239
3240 max = pci_scan_child_bus(bus);
3241 pci_assign_unassigned_bus_resources(bus);
3242 pci_bus_add_devices(bus);
3243
3244 return max;
3245}
3246EXPORT_SYMBOL_GPL(pci_rescan_bus);
3247
3248/*
3249 * pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal
3250 * routines should always be executed under this mutex.
3251 */
3252static DEFINE_MUTEX(pci_rescan_remove_lock);
3253
3254void pci_lock_rescan_remove(void)
3255{
3256 mutex_lock(&pci_rescan_remove_lock);
3257}
3258EXPORT_SYMBOL_GPL(pci_lock_rescan_remove);
3259
3260void pci_unlock_rescan_remove(void)
3261{
3262 mutex_unlock(&pci_rescan_remove_lock);
3263}
3264EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove);
3265
3266static int __init pci_sort_bf_cmp(const struct device *d_a,
3267 const struct device *d_b)
3268{
3269 const struct pci_dev *a = to_pci_dev(d_a);
3270 const struct pci_dev *b = to_pci_dev(d_b);
3271
3272 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
3273 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
3274
3275 if (a->bus->number < b->bus->number) return -1;
3276 else if (a->bus->number > b->bus->number) return 1;
3277
3278 if (a->devfn < b->devfn) return -1;
3279 else if (a->devfn > b->devfn) return 1;
3280
3281 return 0;
3282}
3283
3284void __init pci_sort_breadthfirst(void)
3285{
3286 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);
3287}
3288
3289int pci_hp_add_bridge(struct pci_dev *dev)
3290{
3291 struct pci_bus *parent = dev->bus;
3292 int busnr, start = parent->busn_res.start;
3293 unsigned int available_buses = 0;
3294 int end = parent->busn_res.end;
3295
3296 for (busnr = start; busnr <= end; busnr++) {
3297 if (!pci_find_bus(pci_domain_nr(parent), busnr))
3298 break;
3299 }
3300 if (busnr-- > end) {
3301 pci_err(dev, "No bus number available for hot-added bridge\n");
3302 return -1;
3303 }
3304
3305 /* Scan bridges that are already configured */
3306 busnr = pci_scan_bridge(parent, dev, busnr, 0);
3307
3308 /*
3309 * Distribute the available bus numbers between hotplug-capable
3310 * bridges to make extending the chain later possible.
3311 */
3312 available_buses = end - busnr;
3313
3314 /* Scan bridges that need to be reconfigured */
3315 pci_scan_bridge_extend(parent, dev, busnr, available_buses, 1);
3316
3317 if (!dev->subordinate)
3318 return -1;
3319
3320 return 0;
3321}
3322EXPORT_SYMBOL_GPL(pci_hp_add_bridge);