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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/of_device.h>
11#include <linux/of_pci.h>
12#include <linux/pci_hotplug.h>
13#include <linux/slab.h>
14#include <linux/module.h>
15#include <linux/cpumask.h>
16#include <linux/aer.h>
17#include <linux/acpi.h>
18#include <linux/hypervisor.h>
19#include <linux/irqdomain.h>
20#include <linux/pm_runtime.h>
21#include "pci.h"
22
23#define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
24#define CARDBUS_RESERVE_BUSNR 3
25
26static struct resource busn_resource = {
27 .name = "PCI busn",
28 .start = 0,
29 .end = 255,
30 .flags = IORESOURCE_BUS,
31};
32
33/* Ugh. Need to stop exporting this to modules. */
34LIST_HEAD(pci_root_buses);
35EXPORT_SYMBOL(pci_root_buses);
36
37static LIST_HEAD(pci_domain_busn_res_list);
38
39struct pci_domain_busn_res {
40 struct list_head list;
41 struct resource res;
42 int domain_nr;
43};
44
45static struct resource *get_pci_domain_busn_res(int domain_nr)
46{
47 struct pci_domain_busn_res *r;
48
49 list_for_each_entry(r, &pci_domain_busn_res_list, list)
50 if (r->domain_nr == domain_nr)
51 return &r->res;
52
53 r = kzalloc(sizeof(*r), GFP_KERNEL);
54 if (!r)
55 return NULL;
56
57 r->domain_nr = domain_nr;
58 r->res.start = 0;
59 r->res.end = 0xff;
60 r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
61
62 list_add_tail(&r->list, &pci_domain_busn_res_list);
63
64 return &r->res;
65}
66
67/*
68 * Some device drivers need know if PCI is initiated.
69 * Basically, we think PCI is not initiated when there
70 * is no device to be found on the pci_bus_type.
71 */
72int no_pci_devices(void)
73{
74 struct device *dev;
75 int no_devices;
76
77 dev = bus_find_next_device(&pci_bus_type, NULL);
78 no_devices = (dev == NULL);
79 put_device(dev);
80 return no_devices;
81}
82EXPORT_SYMBOL(no_pci_devices);
83
84/*
85 * PCI Bus Class
86 */
87static void release_pcibus_dev(struct device *dev)
88{
89 struct pci_bus *pci_bus = to_pci_bus(dev);
90
91 put_device(pci_bus->bridge);
92 pci_bus_remove_resources(pci_bus);
93 pci_release_bus_of_node(pci_bus);
94 kfree(pci_bus);
95}
96
97static struct class pcibus_class = {
98 .name = "pci_bus",
99 .dev_release = &release_pcibus_dev,
100 .dev_groups = pcibus_groups,
101};
102
103static int __init pcibus_class_init(void)
104{
105 return class_register(&pcibus_class);
106}
107postcore_initcall(pcibus_class_init);
108
109static u64 pci_size(u64 base, u64 maxbase, u64 mask)
110{
111 u64 size = mask & maxbase; /* Find the significant bits */
112 if (!size)
113 return 0;
114
115 /*
116 * Get the lowest of them to find the decode size, and from that
117 * the extent.
118 */
119 size = size & ~(size-1);
120
121 /*
122 * base == maxbase can be valid only if the BAR has already been
123 * programmed with all 1s.
124 */
125 if (base == maxbase && ((base | (size - 1)) & mask) != mask)
126 return 0;
127
128 return size;
129}
130
131static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
132{
133 u32 mem_type;
134 unsigned long flags;
135
136 if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
137 flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
138 flags |= IORESOURCE_IO;
139 return flags;
140 }
141
142 flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
143 flags |= IORESOURCE_MEM;
144 if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
145 flags |= IORESOURCE_PREFETCH;
146
147 mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
148 switch (mem_type) {
149 case PCI_BASE_ADDRESS_MEM_TYPE_32:
150 break;
151 case PCI_BASE_ADDRESS_MEM_TYPE_1M:
152 /* 1M mem BAR treated as 32-bit BAR */
153 break;
154 case PCI_BASE_ADDRESS_MEM_TYPE_64:
155 flags |= IORESOURCE_MEM_64;
156 break;
157 default:
158 /* mem unknown type treated as 32-bit BAR */
159 break;
160 }
161 return flags;
162}
163
164#define PCI_COMMAND_DECODE_ENABLE (PCI_COMMAND_MEMORY | PCI_COMMAND_IO)
165
166/**
167 * pci_read_base - Read a PCI BAR
168 * @dev: the PCI device
169 * @type: type of the BAR
170 * @res: resource buffer to be filled in
171 * @pos: BAR position in the config space
172 *
173 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
174 */
175int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
176 struct resource *res, unsigned int pos)
177{
178 u32 l = 0, sz = 0, mask;
179 u64 l64, sz64, mask64;
180 u16 orig_cmd;
181 struct pci_bus_region region, inverted_region;
182
183 mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
184
185 /* No printks while decoding is disabled! */
186 if (!dev->mmio_always_on) {
187 pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
188 if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) {
189 pci_write_config_word(dev, PCI_COMMAND,
190 orig_cmd & ~PCI_COMMAND_DECODE_ENABLE);
191 }
192 }
193
194 res->name = pci_name(dev);
195
196 pci_read_config_dword(dev, pos, &l);
197 pci_write_config_dword(dev, pos, l | mask);
198 pci_read_config_dword(dev, pos, &sz);
199 pci_write_config_dword(dev, pos, l);
200
201 /*
202 * All bits set in sz means the device isn't working properly.
203 * If the BAR isn't implemented, all bits must be 0. If it's a
204 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
205 * 1 must be clear.
206 */
207 if (sz == 0xffffffff)
208 sz = 0;
209
210 /*
211 * I don't know how l can have all bits set. Copied from old code.
212 * Maybe it fixes a bug on some ancient platform.
213 */
214 if (l == 0xffffffff)
215 l = 0;
216
217 if (type == pci_bar_unknown) {
218 res->flags = decode_bar(dev, l);
219 res->flags |= IORESOURCE_SIZEALIGN;
220 if (res->flags & IORESOURCE_IO) {
221 l64 = l & PCI_BASE_ADDRESS_IO_MASK;
222 sz64 = sz & PCI_BASE_ADDRESS_IO_MASK;
223 mask64 = PCI_BASE_ADDRESS_IO_MASK & (u32)IO_SPACE_LIMIT;
224 } else {
225 l64 = l & PCI_BASE_ADDRESS_MEM_MASK;
226 sz64 = sz & PCI_BASE_ADDRESS_MEM_MASK;
227 mask64 = (u32)PCI_BASE_ADDRESS_MEM_MASK;
228 }
229 } else {
230 if (l & PCI_ROM_ADDRESS_ENABLE)
231 res->flags |= IORESOURCE_ROM_ENABLE;
232 l64 = l & PCI_ROM_ADDRESS_MASK;
233 sz64 = sz & PCI_ROM_ADDRESS_MASK;
234 mask64 = PCI_ROM_ADDRESS_MASK;
235 }
236
237 if (res->flags & IORESOURCE_MEM_64) {
238 pci_read_config_dword(dev, pos + 4, &l);
239 pci_write_config_dword(dev, pos + 4, ~0);
240 pci_read_config_dword(dev, pos + 4, &sz);
241 pci_write_config_dword(dev, pos + 4, l);
242
243 l64 |= ((u64)l << 32);
244 sz64 |= ((u64)sz << 32);
245 mask64 |= ((u64)~0 << 32);
246 }
247
248 if (!dev->mmio_always_on && (orig_cmd & PCI_COMMAND_DECODE_ENABLE))
249 pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
250
251 if (!sz64)
252 goto fail;
253
254 sz64 = pci_size(l64, sz64, mask64);
255 if (!sz64) {
256 pci_info(dev, FW_BUG "reg 0x%x: invalid BAR (can't size)\n",
257 pos);
258 goto fail;
259 }
260
261 if (res->flags & IORESOURCE_MEM_64) {
262 if ((sizeof(pci_bus_addr_t) < 8 || sizeof(resource_size_t) < 8)
263 && sz64 > 0x100000000ULL) {
264 res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
265 res->start = 0;
266 res->end = 0;
267 pci_err(dev, "reg 0x%x: can't handle BAR larger than 4GB (size %#010llx)\n",
268 pos, (unsigned long long)sz64);
269 goto out;
270 }
271
272 if ((sizeof(pci_bus_addr_t) < 8) && l) {
273 /* Above 32-bit boundary; try to reallocate */
274 res->flags |= IORESOURCE_UNSET;
275 res->start = 0;
276 res->end = sz64 - 1;
277 pci_info(dev, "reg 0x%x: can't handle BAR above 4GB (bus address %#010llx)\n",
278 pos, (unsigned long long)l64);
279 goto out;
280 }
281 }
282
283 region.start = l64;
284 region.end = l64 + sz64 - 1;
285
286 pcibios_bus_to_resource(dev->bus, res, ®ion);
287 pcibios_resource_to_bus(dev->bus, &inverted_region, res);
288
289 /*
290 * If "A" is a BAR value (a bus address), "bus_to_resource(A)" is
291 * the corresponding resource address (the physical address used by
292 * the CPU. Converting that resource address back to a bus address
293 * should yield the original BAR value:
294 *
295 * resource_to_bus(bus_to_resource(A)) == A
296 *
297 * If it doesn't, CPU accesses to "bus_to_resource(A)" will not
298 * be claimed by the device.
299 */
300 if (inverted_region.start != region.start) {
301 res->flags |= IORESOURCE_UNSET;
302 res->start = 0;
303 res->end = region.end - region.start;
304 pci_info(dev, "reg 0x%x: initial BAR value %#010llx invalid\n",
305 pos, (unsigned long long)region.start);
306 }
307
308 goto out;
309
310
311fail:
312 res->flags = 0;
313out:
314 if (res->flags)
315 pci_info(dev, "reg 0x%x: %pR\n", pos, res);
316
317 return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
318}
319
320static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
321{
322 unsigned int pos, reg;
323
324 if (dev->non_compliant_bars)
325 return;
326
327 /* Per PCIe r4.0, sec 9.3.4.1.11, the VF BARs are all RO Zero */
328 if (dev->is_virtfn)
329 return;
330
331 for (pos = 0; pos < howmany; pos++) {
332 struct resource *res = &dev->resource[pos];
333 reg = PCI_BASE_ADDRESS_0 + (pos << 2);
334 pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
335 }
336
337 if (rom) {
338 struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
339 dev->rom_base_reg = rom;
340 res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
341 IORESOURCE_READONLY | IORESOURCE_SIZEALIGN;
342 __pci_read_base(dev, pci_bar_mem32, res, rom);
343 }
344}
345
346static void pci_read_bridge_windows(struct pci_dev *bridge)
347{
348 u16 io;
349 u32 pmem, tmp;
350
351 pci_read_config_word(bridge, PCI_IO_BASE, &io);
352 if (!io) {
353 pci_write_config_word(bridge, PCI_IO_BASE, 0xe0f0);
354 pci_read_config_word(bridge, PCI_IO_BASE, &io);
355 pci_write_config_word(bridge, PCI_IO_BASE, 0x0);
356 }
357 if (io)
358 bridge->io_window = 1;
359
360 /*
361 * DECchip 21050 pass 2 errata: the bridge may miss an address
362 * disconnect boundary by one PCI data phase. Workaround: do not
363 * use prefetching on this device.
364 */
365 if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001)
366 return;
367
368 pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
369 if (!pmem) {
370 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE,
371 0xffe0fff0);
372 pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
373 pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0);
374 }
375 if (!pmem)
376 return;
377
378 bridge->pref_window = 1;
379
380 if ((pmem & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
381
382 /*
383 * Bridge claims to have a 64-bit prefetchable memory
384 * window; verify that the upper bits are actually
385 * writable.
386 */
387 pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &pmem);
388 pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32,
389 0xffffffff);
390 pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &tmp);
391 pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, pmem);
392 if (tmp)
393 bridge->pref_64_window = 1;
394 }
395}
396
397static void pci_read_bridge_io(struct pci_bus *child)
398{
399 struct pci_dev *dev = child->self;
400 u8 io_base_lo, io_limit_lo;
401 unsigned long io_mask, io_granularity, base, limit;
402 struct pci_bus_region region;
403 struct resource *res;
404
405 io_mask = PCI_IO_RANGE_MASK;
406 io_granularity = 0x1000;
407 if (dev->io_window_1k) {
408 /* Support 1K I/O space granularity */
409 io_mask = PCI_IO_1K_RANGE_MASK;
410 io_granularity = 0x400;
411 }
412
413 res = child->resource[0];
414 pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
415 pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
416 base = (io_base_lo & io_mask) << 8;
417 limit = (io_limit_lo & io_mask) << 8;
418
419 if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
420 u16 io_base_hi, io_limit_hi;
421
422 pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
423 pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
424 base |= ((unsigned long) io_base_hi << 16);
425 limit |= ((unsigned long) io_limit_hi << 16);
426 }
427
428 if (base <= limit) {
429 res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
430 region.start = base;
431 region.end = limit + io_granularity - 1;
432 pcibios_bus_to_resource(dev->bus, res, ®ion);
433 pci_info(dev, " bridge window %pR\n", res);
434 }
435}
436
437static void pci_read_bridge_mmio(struct pci_bus *child)
438{
439 struct pci_dev *dev = child->self;
440 u16 mem_base_lo, mem_limit_lo;
441 unsigned long base, limit;
442 struct pci_bus_region region;
443 struct resource *res;
444
445 res = child->resource[1];
446 pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
447 pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
448 base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
449 limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
450 if (base <= limit) {
451 res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
452 region.start = base;
453 region.end = limit + 0xfffff;
454 pcibios_bus_to_resource(dev->bus, res, ®ion);
455 pci_info(dev, " bridge window %pR\n", res);
456 }
457}
458
459static void pci_read_bridge_mmio_pref(struct pci_bus *child)
460{
461 struct pci_dev *dev = child->self;
462 u16 mem_base_lo, mem_limit_lo;
463 u64 base64, limit64;
464 pci_bus_addr_t base, limit;
465 struct pci_bus_region region;
466 struct resource *res;
467
468 res = child->resource[2];
469 pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
470 pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
471 base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
472 limit64 = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
473
474 if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
475 u32 mem_base_hi, mem_limit_hi;
476
477 pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
478 pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
479
480 /*
481 * Some bridges set the base > limit by default, and some
482 * (broken) BIOSes do not initialize them. If we find
483 * this, just assume they are not being used.
484 */
485 if (mem_base_hi <= mem_limit_hi) {
486 base64 |= (u64) mem_base_hi << 32;
487 limit64 |= (u64) mem_limit_hi << 32;
488 }
489 }
490
491 base = (pci_bus_addr_t) base64;
492 limit = (pci_bus_addr_t) limit64;
493
494 if (base != base64) {
495 pci_err(dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
496 (unsigned long long) base64);
497 return;
498 }
499
500 if (base <= limit) {
501 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
502 IORESOURCE_MEM | IORESOURCE_PREFETCH;
503 if (res->flags & PCI_PREF_RANGE_TYPE_64)
504 res->flags |= IORESOURCE_MEM_64;
505 region.start = base;
506 region.end = limit + 0xfffff;
507 pcibios_bus_to_resource(dev->bus, res, ®ion);
508 pci_info(dev, " bridge window %pR\n", res);
509 }
510}
511
512void pci_read_bridge_bases(struct pci_bus *child)
513{
514 struct pci_dev *dev = child->self;
515 struct resource *res;
516 int i;
517
518 if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
519 return;
520
521 pci_info(dev, "PCI bridge to %pR%s\n",
522 &child->busn_res,
523 dev->transparent ? " (subtractive decode)" : "");
524
525 pci_bus_remove_resources(child);
526 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
527 child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
528
529 pci_read_bridge_io(child);
530 pci_read_bridge_mmio(child);
531 pci_read_bridge_mmio_pref(child);
532
533 if (dev->transparent) {
534 pci_bus_for_each_resource(child->parent, res, i) {
535 if (res && res->flags) {
536 pci_bus_add_resource(child, res,
537 PCI_SUBTRACTIVE_DECODE);
538 pci_info(dev, " bridge window %pR (subtractive decode)\n",
539 res);
540 }
541 }
542 }
543}
544
545static struct pci_bus *pci_alloc_bus(struct pci_bus *parent)
546{
547 struct pci_bus *b;
548
549 b = kzalloc(sizeof(*b), GFP_KERNEL);
550 if (!b)
551 return NULL;
552
553 INIT_LIST_HEAD(&b->node);
554 INIT_LIST_HEAD(&b->children);
555 INIT_LIST_HEAD(&b->devices);
556 INIT_LIST_HEAD(&b->slots);
557 INIT_LIST_HEAD(&b->resources);
558 b->max_bus_speed = PCI_SPEED_UNKNOWN;
559 b->cur_bus_speed = PCI_SPEED_UNKNOWN;
560#ifdef CONFIG_PCI_DOMAINS_GENERIC
561 if (parent)
562 b->domain_nr = parent->domain_nr;
563#endif
564 return b;
565}
566
567static void devm_pci_release_host_bridge_dev(struct device *dev)
568{
569 struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
570
571 if (bridge->release_fn)
572 bridge->release_fn(bridge);
573
574 pci_free_resource_list(&bridge->windows);
575}
576
577static void pci_release_host_bridge_dev(struct device *dev)
578{
579 devm_pci_release_host_bridge_dev(dev);
580 kfree(to_pci_host_bridge(dev));
581}
582
583static void pci_init_host_bridge(struct pci_host_bridge *bridge)
584{
585 INIT_LIST_HEAD(&bridge->windows);
586 INIT_LIST_HEAD(&bridge->dma_ranges);
587
588 /*
589 * We assume we can manage these PCIe features. Some systems may
590 * reserve these for use by the platform itself, e.g., an ACPI BIOS
591 * may implement its own AER handling and use _OSC to prevent the
592 * OS from interfering.
593 */
594 bridge->native_aer = 1;
595 bridge->native_pcie_hotplug = 1;
596 bridge->native_shpc_hotplug = 1;
597 bridge->native_pme = 1;
598 bridge->native_ltr = 1;
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
616struct pci_host_bridge *devm_pci_alloc_host_bridge(struct device *dev,
617 size_t priv)
618{
619 struct pci_host_bridge *bridge;
620
621 bridge = devm_kzalloc(dev, sizeof(*bridge) + priv, GFP_KERNEL);
622 if (!bridge)
623 return NULL;
624
625 pci_init_host_bridge(bridge);
626 bridge->dev.release = devm_pci_release_host_bridge_dev;
627
628 return bridge;
629}
630EXPORT_SYMBOL(devm_pci_alloc_host_bridge);
631
632void pci_free_host_bridge(struct pci_host_bridge *bridge)
633{
634 pci_free_resource_list(&bridge->windows);
635 pci_free_resource_list(&bridge->dma_ranges);
636
637 kfree(bridge);
638}
639EXPORT_SYMBOL(pci_free_host_bridge);
640
641static const unsigned char pcix_bus_speed[] = {
642 PCI_SPEED_UNKNOWN, /* 0 */
643 PCI_SPEED_66MHz_PCIX, /* 1 */
644 PCI_SPEED_100MHz_PCIX, /* 2 */
645 PCI_SPEED_133MHz_PCIX, /* 3 */
646 PCI_SPEED_UNKNOWN, /* 4 */
647 PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
648 PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
649 PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
650 PCI_SPEED_UNKNOWN, /* 8 */
651 PCI_SPEED_66MHz_PCIX_266, /* 9 */
652 PCI_SPEED_100MHz_PCIX_266, /* A */
653 PCI_SPEED_133MHz_PCIX_266, /* B */
654 PCI_SPEED_UNKNOWN, /* C */
655 PCI_SPEED_66MHz_PCIX_533, /* D */
656 PCI_SPEED_100MHz_PCIX_533, /* E */
657 PCI_SPEED_133MHz_PCIX_533 /* F */
658};
659
660const unsigned char pcie_link_speed[] = {
661 PCI_SPEED_UNKNOWN, /* 0 */
662 PCIE_SPEED_2_5GT, /* 1 */
663 PCIE_SPEED_5_0GT, /* 2 */
664 PCIE_SPEED_8_0GT, /* 3 */
665 PCIE_SPEED_16_0GT, /* 4 */
666 PCIE_SPEED_32_0GT, /* 5 */
667 PCI_SPEED_UNKNOWN, /* 6 */
668 PCI_SPEED_UNKNOWN, /* 7 */
669 PCI_SPEED_UNKNOWN, /* 8 */
670 PCI_SPEED_UNKNOWN, /* 9 */
671 PCI_SPEED_UNKNOWN, /* A */
672 PCI_SPEED_UNKNOWN, /* B */
673 PCI_SPEED_UNKNOWN, /* C */
674 PCI_SPEED_UNKNOWN, /* D */
675 PCI_SPEED_UNKNOWN, /* E */
676 PCI_SPEED_UNKNOWN /* F */
677};
678
679void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
680{
681 bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS];
682}
683EXPORT_SYMBOL_GPL(pcie_update_link_speed);
684
685static unsigned char agp_speeds[] = {
686 AGP_UNKNOWN,
687 AGP_1X,
688 AGP_2X,
689 AGP_4X,
690 AGP_8X
691};
692
693static enum pci_bus_speed agp_speed(int agp3, int agpstat)
694{
695 int index = 0;
696
697 if (agpstat & 4)
698 index = 3;
699 else if (agpstat & 2)
700 index = 2;
701 else if (agpstat & 1)
702 index = 1;
703 else
704 goto out;
705
706 if (agp3) {
707 index += 2;
708 if (index == 5)
709 index = 0;
710 }
711
712 out:
713 return agp_speeds[index];
714}
715
716static void pci_set_bus_speed(struct pci_bus *bus)
717{
718 struct pci_dev *bridge = bus->self;
719 int pos;
720
721 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
722 if (!pos)
723 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
724 if (pos) {
725 u32 agpstat, agpcmd;
726
727 pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
728 bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
729
730 pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
731 bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
732 }
733
734 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
735 if (pos) {
736 u16 status;
737 enum pci_bus_speed max;
738
739 pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
740 &status);
741
742 if (status & PCI_X_SSTATUS_533MHZ) {
743 max = PCI_SPEED_133MHz_PCIX_533;
744 } else if (status & PCI_X_SSTATUS_266MHZ) {
745 max = PCI_SPEED_133MHz_PCIX_266;
746 } else if (status & PCI_X_SSTATUS_133MHZ) {
747 if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2)
748 max = PCI_SPEED_133MHz_PCIX_ECC;
749 else
750 max = PCI_SPEED_133MHz_PCIX;
751 } else {
752 max = PCI_SPEED_66MHz_PCIX;
753 }
754
755 bus->max_bus_speed = max;
756 bus->cur_bus_speed = pcix_bus_speed[
757 (status & PCI_X_SSTATUS_FREQ) >> 6];
758
759 return;
760 }
761
762 if (pci_is_pcie(bridge)) {
763 u32 linkcap;
764 u16 linksta;
765
766 pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
767 bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
768 bridge->link_active_reporting = !!(linkcap & PCI_EXP_LNKCAP_DLLLARC);
769
770 pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
771 pcie_update_link_speed(bus, linksta);
772 }
773}
774
775static struct irq_domain *pci_host_bridge_msi_domain(struct pci_bus *bus)
776{
777 struct irq_domain *d;
778
779 /*
780 * Any firmware interface that can resolve the msi_domain
781 * should be called from here.
782 */
783 d = pci_host_bridge_of_msi_domain(bus);
784 if (!d)
785 d = pci_host_bridge_acpi_msi_domain(bus);
786
787#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
788 /*
789 * If no IRQ domain was found via the OF tree, try looking it up
790 * directly through the fwnode_handle.
791 */
792 if (!d) {
793 struct fwnode_handle *fwnode = pci_root_bus_fwnode(bus);
794
795 if (fwnode)
796 d = irq_find_matching_fwnode(fwnode,
797 DOMAIN_BUS_PCI_MSI);
798 }
799#endif
800
801 return d;
802}
803
804static void pci_set_bus_msi_domain(struct pci_bus *bus)
805{
806 struct irq_domain *d;
807 struct pci_bus *b;
808
809 /*
810 * The bus can be a root bus, a subordinate bus, or a virtual bus
811 * created by an SR-IOV device. Walk up to the first bridge device
812 * found or derive the domain from the host bridge.
813 */
814 for (b = bus, d = NULL; !d && !pci_is_root_bus(b); b = b->parent) {
815 if (b->self)
816 d = dev_get_msi_domain(&b->self->dev);
817 }
818
819 if (!d)
820 d = pci_host_bridge_msi_domain(b);
821
822 dev_set_msi_domain(&bus->dev, d);
823}
824
825static int pci_register_host_bridge(struct pci_host_bridge *bridge)
826{
827 struct device *parent = bridge->dev.parent;
828 struct resource_entry *window, *n;
829 struct pci_bus *bus, *b;
830 resource_size_t offset;
831 LIST_HEAD(resources);
832 struct resource *res;
833 char addr[64], *fmt;
834 const char *name;
835 int err;
836
837 bus = pci_alloc_bus(NULL);
838 if (!bus)
839 return -ENOMEM;
840
841 bridge->bus = bus;
842
843 /* Temporarily move resources off the list */
844 list_splice_init(&bridge->windows, &resources);
845 bus->sysdata = bridge->sysdata;
846 bus->msi = bridge->msi;
847 bus->ops = bridge->ops;
848 bus->number = bus->busn_res.start = bridge->busnr;
849#ifdef CONFIG_PCI_DOMAINS_GENERIC
850 bus->domain_nr = pci_bus_find_domain_nr(bus, parent);
851#endif
852
853 b = pci_find_bus(pci_domain_nr(bus), bridge->busnr);
854 if (b) {
855 /* Ignore it if we already got here via a different bridge */
856 dev_dbg(&b->dev, "bus already known\n");
857 err = -EEXIST;
858 goto free;
859 }
860
861 dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(bus),
862 bridge->busnr);
863
864 err = pcibios_root_bridge_prepare(bridge);
865 if (err)
866 goto free;
867
868 err = device_register(&bridge->dev);
869 if (err)
870 put_device(&bridge->dev);
871
872 bus->bridge = get_device(&bridge->dev);
873 device_enable_async_suspend(bus->bridge);
874 pci_set_bus_of_node(bus);
875 pci_set_bus_msi_domain(bus);
876
877 if (!parent)
878 set_dev_node(bus->bridge, pcibus_to_node(bus));
879
880 bus->dev.class = &pcibus_class;
881 bus->dev.parent = bus->bridge;
882
883 dev_set_name(&bus->dev, "%04x:%02x", pci_domain_nr(bus), bus->number);
884 name = dev_name(&bus->dev);
885
886 err = device_register(&bus->dev);
887 if (err)
888 goto unregister;
889
890 pcibios_add_bus(bus);
891
892 /* Create legacy_io and legacy_mem files for this bus */
893 pci_create_legacy_files(bus);
894
895 if (parent)
896 dev_info(parent, "PCI host bridge to bus %s\n", name);
897 else
898 pr_info("PCI host bridge to bus %s\n", name);
899
900 /* Add initial resources to the bus */
901 resource_list_for_each_entry_safe(window, n, &resources) {
902 list_move_tail(&window->node, &bridge->windows);
903 offset = window->offset;
904 res = window->res;
905
906 if (res->flags & IORESOURCE_BUS)
907 pci_bus_insert_busn_res(bus, bus->number, res->end);
908 else
909 pci_bus_add_resource(bus, res, 0);
910
911 if (offset) {
912 if (resource_type(res) == IORESOURCE_IO)
913 fmt = " (bus address [%#06llx-%#06llx])";
914 else
915 fmt = " (bus address [%#010llx-%#010llx])";
916
917 snprintf(addr, sizeof(addr), fmt,
918 (unsigned long long)(res->start - offset),
919 (unsigned long long)(res->end - offset));
920 } else
921 addr[0] = '\0';
922
923 dev_info(&bus->dev, "root bus resource %pR%s\n", res, addr);
924 }
925
926 down_write(&pci_bus_sem);
927 list_add_tail(&bus->node, &pci_root_buses);
928 up_write(&pci_bus_sem);
929
930 return 0;
931
932unregister:
933 put_device(&bridge->dev);
934 device_unregister(&bridge->dev);
935
936free:
937 kfree(bus);
938 return err;
939}
940
941static bool pci_bridge_child_ext_cfg_accessible(struct pci_dev *bridge)
942{
943 int pos;
944 u32 status;
945
946 /*
947 * If extended config space isn't accessible on a bridge's primary
948 * bus, we certainly can't access it on the secondary bus.
949 */
950 if (bridge->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG)
951 return false;
952
953 /*
954 * PCIe Root Ports and switch ports are PCIe on both sides, so if
955 * extended config space is accessible on the primary, it's also
956 * accessible on the secondary.
957 */
958 if (pci_is_pcie(bridge) &&
959 (pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT ||
960 pci_pcie_type(bridge) == PCI_EXP_TYPE_UPSTREAM ||
961 pci_pcie_type(bridge) == PCI_EXP_TYPE_DOWNSTREAM))
962 return true;
963
964 /*
965 * For the other bridge types:
966 * - PCI-to-PCI bridges
967 * - PCIe-to-PCI/PCI-X forward bridges
968 * - PCI/PCI-X-to-PCIe reverse bridges
969 * extended config space on the secondary side is only accessible
970 * if the bridge supports PCI-X Mode 2.
971 */
972 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
973 if (!pos)
974 return false;
975
976 pci_read_config_dword(bridge, pos + PCI_X_STATUS, &status);
977 return status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ);
978}
979
980static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
981 struct pci_dev *bridge, int busnr)
982{
983 struct pci_bus *child;
984 int i;
985 int ret;
986
987 /* Allocate a new bus and inherit stuff from the parent */
988 child = pci_alloc_bus(parent);
989 if (!child)
990 return NULL;
991
992 child->parent = parent;
993 child->ops = parent->ops;
994 child->msi = parent->msi;
995 child->sysdata = parent->sysdata;
996 child->bus_flags = parent->bus_flags;
997
998 /*
999 * Initialize some portions of the bus device, but don't register
1000 * it now as the parent is not properly set up yet.
1001 */
1002 child->dev.class = &pcibus_class;
1003 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
1004
1005 /* Set up the primary, secondary and subordinate bus numbers */
1006 child->number = child->busn_res.start = busnr;
1007 child->primary = parent->busn_res.start;
1008 child->busn_res.end = 0xff;
1009
1010 if (!bridge) {
1011 child->dev.parent = parent->bridge;
1012 goto add_dev;
1013 }
1014
1015 child->self = bridge;
1016 child->bridge = get_device(&bridge->dev);
1017 child->dev.parent = child->bridge;
1018 pci_set_bus_of_node(child);
1019 pci_set_bus_speed(child);
1020
1021 /*
1022 * Check whether extended config space is accessible on the child
1023 * bus. Note that we currently assume it is always accessible on
1024 * the root bus.
1025 */
1026 if (!pci_bridge_child_ext_cfg_accessible(bridge)) {
1027 child->bus_flags |= PCI_BUS_FLAGS_NO_EXTCFG;
1028 pci_info(child, "extended config space not accessible\n");
1029 }
1030
1031 /* Set up default resource pointers and names */
1032 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
1033 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
1034 child->resource[i]->name = child->name;
1035 }
1036 bridge->subordinate = child;
1037
1038add_dev:
1039 pci_set_bus_msi_domain(child);
1040 ret = device_register(&child->dev);
1041 WARN_ON(ret < 0);
1042
1043 pcibios_add_bus(child);
1044
1045 if (child->ops->add_bus) {
1046 ret = child->ops->add_bus(child);
1047 if (WARN_ON(ret < 0))
1048 dev_err(&child->dev, "failed to add bus: %d\n", ret);
1049 }
1050
1051 /* Create legacy_io and legacy_mem files for this bus */
1052 pci_create_legacy_files(child);
1053
1054 return child;
1055}
1056
1057struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev,
1058 int busnr)
1059{
1060 struct pci_bus *child;
1061
1062 child = pci_alloc_child_bus(parent, dev, busnr);
1063 if (child) {
1064 down_write(&pci_bus_sem);
1065 list_add_tail(&child->node, &parent->children);
1066 up_write(&pci_bus_sem);
1067 }
1068 return child;
1069}
1070EXPORT_SYMBOL(pci_add_new_bus);
1071
1072static void pci_enable_crs(struct pci_dev *pdev)
1073{
1074 u16 root_cap = 0;
1075
1076 /* Enable CRS Software Visibility if supported */
1077 pcie_capability_read_word(pdev, PCI_EXP_RTCAP, &root_cap);
1078 if (root_cap & PCI_EXP_RTCAP_CRSVIS)
1079 pcie_capability_set_word(pdev, PCI_EXP_RTCTL,
1080 PCI_EXP_RTCTL_CRSSVE);
1081}
1082
1083static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
1084 unsigned int available_buses);
1085/**
1086 * pci_ea_fixed_busnrs() - Read fixed Secondary and Subordinate bus
1087 * numbers from EA capability.
1088 * @dev: Bridge
1089 * @sec: updated with secondary bus number from EA
1090 * @sub: updated with subordinate bus number from EA
1091 *
1092 * If @dev is a bridge with EA capability, update @sec and @sub with
1093 * fixed bus numbers from the capability and return true. Otherwise,
1094 * return false.
1095 */
1096static bool pci_ea_fixed_busnrs(struct pci_dev *dev, u8 *sec, u8 *sub)
1097{
1098 int ea, offset;
1099 u32 dw;
1100
1101 if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE)
1102 return false;
1103
1104 /* find PCI EA capability in list */
1105 ea = pci_find_capability(dev, PCI_CAP_ID_EA);
1106 if (!ea)
1107 return false;
1108
1109 offset = ea + PCI_EA_FIRST_ENT;
1110 pci_read_config_dword(dev, offset, &dw);
1111 *sec = dw & PCI_EA_SEC_BUS_MASK;
1112 *sub = (dw & PCI_EA_SUB_BUS_MASK) >> PCI_EA_SUB_BUS_SHIFT;
1113 return true;
1114}
1115
1116/*
1117 * pci_scan_bridge_extend() - Scan buses behind a bridge
1118 * @bus: Parent bus the bridge is on
1119 * @dev: Bridge itself
1120 * @max: Starting subordinate number of buses behind this bridge
1121 * @available_buses: Total number of buses available for this bridge and
1122 * the devices below. After the minimal bus space has
1123 * been allocated the remaining buses will be
1124 * distributed equally between hotplug-capable bridges.
1125 * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges
1126 * that need to be reconfigured.
1127 *
1128 * If it's a bridge, configure it and scan the bus behind it.
1129 * For CardBus bridges, we don't scan behind as the devices will
1130 * be handled by the bridge driver itself.
1131 *
1132 * We need to process bridges in two passes -- first we scan those
1133 * already configured by the BIOS and after we are done with all of
1134 * them, we proceed to assigning numbers to the remaining buses in
1135 * order to avoid overlaps between old and new bus numbers.
1136 *
1137 * Return: New subordinate number covering all buses behind this bridge.
1138 */
1139static int pci_scan_bridge_extend(struct pci_bus *bus, struct pci_dev *dev,
1140 int max, unsigned int available_buses,
1141 int pass)
1142{
1143 struct pci_bus *child;
1144 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
1145 u32 buses, i, j = 0;
1146 u16 bctl;
1147 u8 primary, secondary, subordinate;
1148 int broken = 0;
1149 bool fixed_buses;
1150 u8 fixed_sec, fixed_sub;
1151 int next_busnr;
1152
1153 /*
1154 * Make sure the bridge is powered on to be able to access config
1155 * space of devices below it.
1156 */
1157 pm_runtime_get_sync(&dev->dev);
1158
1159 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
1160 primary = buses & 0xFF;
1161 secondary = (buses >> 8) & 0xFF;
1162 subordinate = (buses >> 16) & 0xFF;
1163
1164 pci_dbg(dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
1165 secondary, subordinate, pass);
1166
1167 if (!primary && (primary != bus->number) && secondary && subordinate) {
1168 pci_warn(dev, "Primary bus is hard wired to 0\n");
1169 primary = bus->number;
1170 }
1171
1172 /* Check if setup is sensible at all */
1173 if (!pass &&
1174 (primary != bus->number || secondary <= bus->number ||
1175 secondary > subordinate)) {
1176 pci_info(dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
1177 secondary, subordinate);
1178 broken = 1;
1179 }
1180
1181 /*
1182 * Disable Master-Abort Mode during probing to avoid reporting of
1183 * bus errors in some architectures.
1184 */
1185 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
1186 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
1187 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
1188
1189 pci_enable_crs(dev);
1190
1191 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
1192 !is_cardbus && !broken) {
1193 unsigned int cmax;
1194
1195 /*
1196 * Bus already configured by firmware, process it in the
1197 * first pass and just note the configuration.
1198 */
1199 if (pass)
1200 goto out;
1201
1202 /*
1203 * The bus might already exist for two reasons: Either we
1204 * are rescanning the bus or the bus is reachable through
1205 * more than one bridge. The second case can happen with
1206 * the i450NX chipset.
1207 */
1208 child = pci_find_bus(pci_domain_nr(bus), secondary);
1209 if (!child) {
1210 child = pci_add_new_bus(bus, dev, secondary);
1211 if (!child)
1212 goto out;
1213 child->primary = primary;
1214 pci_bus_insert_busn_res(child, secondary, subordinate);
1215 child->bridge_ctl = bctl;
1216 }
1217
1218 cmax = pci_scan_child_bus(child);
1219 if (cmax > subordinate)
1220 pci_warn(dev, "bridge has subordinate %02x but max busn %02x\n",
1221 subordinate, cmax);
1222
1223 /* Subordinate should equal child->busn_res.end */
1224 if (subordinate > max)
1225 max = subordinate;
1226 } else {
1227
1228 /*
1229 * We need to assign a number to this bus which we always
1230 * do in the second pass.
1231 */
1232 if (!pass) {
1233 if (pcibios_assign_all_busses() || broken || is_cardbus)
1234
1235 /*
1236 * Temporarily disable forwarding of the
1237 * configuration cycles on all bridges in
1238 * this bus segment to avoid possible
1239 * conflicts in the second pass between two
1240 * bridges programmed with overlapping bus
1241 * ranges.
1242 */
1243 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
1244 buses & ~0xffffff);
1245 goto out;
1246 }
1247
1248 /* Clear errors */
1249 pci_write_config_word(dev, PCI_STATUS, 0xffff);
1250
1251 /* Read bus numbers from EA Capability (if present) */
1252 fixed_buses = pci_ea_fixed_busnrs(dev, &fixed_sec, &fixed_sub);
1253 if (fixed_buses)
1254 next_busnr = fixed_sec;
1255 else
1256 next_busnr = max + 1;
1257
1258 /*
1259 * Prevent assigning a bus number that already exists.
1260 * This can happen when a bridge is hot-plugged, so in this
1261 * case we only re-scan this bus.
1262 */
1263 child = pci_find_bus(pci_domain_nr(bus), next_busnr);
1264 if (!child) {
1265 child = pci_add_new_bus(bus, dev, next_busnr);
1266 if (!child)
1267 goto out;
1268 pci_bus_insert_busn_res(child, next_busnr,
1269 bus->busn_res.end);
1270 }
1271 max++;
1272 if (available_buses)
1273 available_buses--;
1274
1275 buses = (buses & 0xff000000)
1276 | ((unsigned int)(child->primary) << 0)
1277 | ((unsigned int)(child->busn_res.start) << 8)
1278 | ((unsigned int)(child->busn_res.end) << 16);
1279
1280 /*
1281 * yenta.c forces a secondary latency timer of 176.
1282 * Copy that behaviour here.
1283 */
1284 if (is_cardbus) {
1285 buses &= ~0xff000000;
1286 buses |= CARDBUS_LATENCY_TIMER << 24;
1287 }
1288
1289 /* We need to blast all three values with a single write */
1290 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
1291
1292 if (!is_cardbus) {
1293 child->bridge_ctl = bctl;
1294 max = pci_scan_child_bus_extend(child, available_buses);
1295 } else {
1296
1297 /*
1298 * For CardBus bridges, we leave 4 bus numbers as
1299 * cards with a PCI-to-PCI bridge can be inserted
1300 * later.
1301 */
1302 for (i = 0; i < CARDBUS_RESERVE_BUSNR; i++) {
1303 struct pci_bus *parent = bus;
1304 if (pci_find_bus(pci_domain_nr(bus),
1305 max+i+1))
1306 break;
1307 while (parent->parent) {
1308 if ((!pcibios_assign_all_busses()) &&
1309 (parent->busn_res.end > max) &&
1310 (parent->busn_res.end <= max+i)) {
1311 j = 1;
1312 }
1313 parent = parent->parent;
1314 }
1315 if (j) {
1316
1317 /*
1318 * Often, there are two CardBus
1319 * bridges -- try to leave one
1320 * valid bus number for each one.
1321 */
1322 i /= 2;
1323 break;
1324 }
1325 }
1326 max += i;
1327 }
1328
1329 /*
1330 * Set subordinate bus number to its real value.
1331 * If fixed subordinate bus number exists from EA
1332 * capability then use it.
1333 */
1334 if (fixed_buses)
1335 max = fixed_sub;
1336 pci_bus_update_busn_res_end(child, max);
1337 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
1338 }
1339
1340 sprintf(child->name,
1341 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
1342 pci_domain_nr(bus), child->number);
1343
1344 /* Check that all devices are accessible */
1345 while (bus->parent) {
1346 if ((child->busn_res.end > bus->busn_res.end) ||
1347 (child->number > bus->busn_res.end) ||
1348 (child->number < bus->number) ||
1349 (child->busn_res.end < bus->number)) {
1350 dev_info(&dev->dev, "devices behind bridge are unusable because %pR cannot be assigned for them\n",
1351 &child->busn_res);
1352 break;
1353 }
1354 bus = bus->parent;
1355 }
1356
1357out:
1358 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
1359
1360 pm_runtime_put(&dev->dev);
1361
1362 return max;
1363}
1364
1365/*
1366 * pci_scan_bridge() - Scan buses behind a bridge
1367 * @bus: Parent bus the bridge is on
1368 * @dev: Bridge itself
1369 * @max: Starting subordinate number of buses behind this bridge
1370 * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges
1371 * that need to be reconfigured.
1372 *
1373 * If it's a bridge, configure it and scan the bus behind it.
1374 * For CardBus bridges, we don't scan behind as the devices will
1375 * be handled by the bridge driver itself.
1376 *
1377 * We need to process bridges in two passes -- first we scan those
1378 * already configured by the BIOS and after we are done with all of
1379 * them, we proceed to assigning numbers to the remaining buses in
1380 * order to avoid overlaps between old and new bus numbers.
1381 *
1382 * Return: New subordinate number covering all buses behind this bridge.
1383 */
1384int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
1385{
1386 return pci_scan_bridge_extend(bus, dev, max, 0, pass);
1387}
1388EXPORT_SYMBOL(pci_scan_bridge);
1389
1390/*
1391 * Read interrupt line and base address registers.
1392 * The architecture-dependent code can tweak these, of course.
1393 */
1394static void pci_read_irq(struct pci_dev *dev)
1395{
1396 unsigned char irq;
1397
1398 /* VFs are not allowed to use INTx, so skip the config reads */
1399 if (dev->is_virtfn) {
1400 dev->pin = 0;
1401 dev->irq = 0;
1402 return;
1403 }
1404
1405 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
1406 dev->pin = irq;
1407 if (irq)
1408 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
1409 dev->irq = irq;
1410}
1411
1412void set_pcie_port_type(struct pci_dev *pdev)
1413{
1414 int pos;
1415 u16 reg16;
1416 int type;
1417 struct pci_dev *parent;
1418
1419 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
1420 if (!pos)
1421 return;
1422
1423 pdev->pcie_cap = pos;
1424 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
1425 pdev->pcie_flags_reg = reg16;
1426 pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16);
1427 pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
1428
1429 parent = pci_upstream_bridge(pdev);
1430 if (!parent)
1431 return;
1432
1433 /*
1434 * Some systems do not identify their upstream/downstream ports
1435 * correctly so detect impossible configurations here and correct
1436 * the port type accordingly.
1437 */
1438 type = pci_pcie_type(pdev);
1439 if (type == PCI_EXP_TYPE_DOWNSTREAM) {
1440 /*
1441 * If pdev claims to be downstream port but the parent
1442 * device is also downstream port assume pdev is actually
1443 * upstream port.
1444 */
1445 if (pcie_downstream_port(parent)) {
1446 pci_info(pdev, "claims to be downstream port but is acting as upstream port, correcting type\n");
1447 pdev->pcie_flags_reg &= ~PCI_EXP_FLAGS_TYPE;
1448 pdev->pcie_flags_reg |= PCI_EXP_TYPE_UPSTREAM;
1449 }
1450 } else if (type == PCI_EXP_TYPE_UPSTREAM) {
1451 /*
1452 * If pdev claims to be upstream port but the parent
1453 * device is also upstream port assume pdev is actually
1454 * downstream port.
1455 */
1456 if (pci_pcie_type(parent) == PCI_EXP_TYPE_UPSTREAM) {
1457 pci_info(pdev, "claims to be upstream port but is acting as downstream port, correcting type\n");
1458 pdev->pcie_flags_reg &= ~PCI_EXP_FLAGS_TYPE;
1459 pdev->pcie_flags_reg |= PCI_EXP_TYPE_DOWNSTREAM;
1460 }
1461 }
1462}
1463
1464void set_pcie_hotplug_bridge(struct pci_dev *pdev)
1465{
1466 u32 reg32;
1467
1468 pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32);
1469 if (reg32 & PCI_EXP_SLTCAP_HPC)
1470 pdev->is_hotplug_bridge = 1;
1471}
1472
1473static void set_pcie_thunderbolt(struct pci_dev *dev)
1474{
1475 int vsec = 0;
1476 u32 header;
1477
1478 while ((vsec = pci_find_next_ext_capability(dev, vsec,
1479 PCI_EXT_CAP_ID_VNDR))) {
1480 pci_read_config_dword(dev, vsec + PCI_VNDR_HEADER, &header);
1481
1482 /* Is the device part of a Thunderbolt controller? */
1483 if (dev->vendor == PCI_VENDOR_ID_INTEL &&
1484 PCI_VNDR_HEADER_ID(header) == PCI_VSEC_ID_INTEL_TBT) {
1485 dev->is_thunderbolt = 1;
1486 return;
1487 }
1488 }
1489}
1490
1491static void set_pcie_untrusted(struct pci_dev *dev)
1492{
1493 struct pci_dev *parent;
1494
1495 /*
1496 * If the upstream bridge is untrusted we treat this device
1497 * untrusted as well.
1498 */
1499 parent = pci_upstream_bridge(dev);
1500 if (parent && parent->untrusted)
1501 dev->untrusted = true;
1502}
1503
1504/**
1505 * pci_ext_cfg_is_aliased - Is ext config space just an alias of std config?
1506 * @dev: PCI device
1507 *
1508 * PCI Express to PCI/PCI-X Bridge Specification, rev 1.0, 4.1.4 says that
1509 * when forwarding a type1 configuration request the bridge must check that
1510 * the extended register address field is zero. The bridge is not permitted
1511 * to forward the transactions and must handle it as an Unsupported Request.
1512 * Some bridges do not follow this rule and simply drop the extended register
1513 * bits, resulting in the standard config space being aliased, every 256
1514 * bytes across the entire configuration space. Test for this condition by
1515 * comparing the first dword of each potential alias to the vendor/device ID.
1516 * Known offenders:
1517 * ASM1083/1085 PCIe-to-PCI Reversible Bridge (1b21:1080, rev 01 & 03)
1518 * AMD/ATI SBx00 PCI to PCI Bridge (1002:4384, rev 40)
1519 */
1520static bool pci_ext_cfg_is_aliased(struct pci_dev *dev)
1521{
1522#ifdef CONFIG_PCI_QUIRKS
1523 int pos;
1524 u32 header, tmp;
1525
1526 pci_read_config_dword(dev, PCI_VENDOR_ID, &header);
1527
1528 for (pos = PCI_CFG_SPACE_SIZE;
1529 pos < PCI_CFG_SPACE_EXP_SIZE; pos += PCI_CFG_SPACE_SIZE) {
1530 if (pci_read_config_dword(dev, pos, &tmp) != PCIBIOS_SUCCESSFUL
1531 || header != tmp)
1532 return false;
1533 }
1534
1535 return true;
1536#else
1537 return false;
1538#endif
1539}
1540
1541/**
1542 * pci_cfg_space_size - Get the configuration space size of the PCI device
1543 * @dev: PCI device
1544 *
1545 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1546 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1547 * access it. Maybe we don't have a way to generate extended config space
1548 * accesses, or the device is behind a reverse Express bridge. So we try
1549 * reading the dword at 0x100 which must either be 0 or a valid extended
1550 * capability header.
1551 */
1552static int pci_cfg_space_size_ext(struct pci_dev *dev)
1553{
1554 u32 status;
1555 int pos = PCI_CFG_SPACE_SIZE;
1556
1557 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1558 return PCI_CFG_SPACE_SIZE;
1559 if (status == 0xffffffff || pci_ext_cfg_is_aliased(dev))
1560 return PCI_CFG_SPACE_SIZE;
1561
1562 return PCI_CFG_SPACE_EXP_SIZE;
1563}
1564
1565int pci_cfg_space_size(struct pci_dev *dev)
1566{
1567 int pos;
1568 u32 status;
1569 u16 class;
1570
1571#ifdef CONFIG_PCI_IOV
1572 /*
1573 * Per the SR-IOV specification (rev 1.1, sec 3.5), VFs are required to
1574 * implement a PCIe capability and therefore must implement extended
1575 * config space. We can skip the NO_EXTCFG test below and the
1576 * reachability/aliasing test in pci_cfg_space_size_ext() by virtue of
1577 * the fact that the SR-IOV capability on the PF resides in extended
1578 * config space and must be accessible and non-aliased to have enabled
1579 * support for this VF. This is a micro performance optimization for
1580 * systems supporting many VFs.
1581 */
1582 if (dev->is_virtfn)
1583 return PCI_CFG_SPACE_EXP_SIZE;
1584#endif
1585
1586 if (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG)
1587 return PCI_CFG_SPACE_SIZE;
1588
1589 class = dev->class >> 8;
1590 if (class == PCI_CLASS_BRIDGE_HOST)
1591 return pci_cfg_space_size_ext(dev);
1592
1593 if (pci_is_pcie(dev))
1594 return pci_cfg_space_size_ext(dev);
1595
1596 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1597 if (!pos)
1598 return PCI_CFG_SPACE_SIZE;
1599
1600 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1601 if (status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ))
1602 return pci_cfg_space_size_ext(dev);
1603
1604 return PCI_CFG_SPACE_SIZE;
1605}
1606
1607static u32 pci_class(struct pci_dev *dev)
1608{
1609 u32 class;
1610
1611#ifdef CONFIG_PCI_IOV
1612 if (dev->is_virtfn)
1613 return dev->physfn->sriov->class;
1614#endif
1615 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
1616 return class;
1617}
1618
1619static void pci_subsystem_ids(struct pci_dev *dev, u16 *vendor, u16 *device)
1620{
1621#ifdef CONFIG_PCI_IOV
1622 if (dev->is_virtfn) {
1623 *vendor = dev->physfn->sriov->subsystem_vendor;
1624 *device = dev->physfn->sriov->subsystem_device;
1625 return;
1626 }
1627#endif
1628 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, vendor);
1629 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, device);
1630}
1631
1632static u8 pci_hdr_type(struct pci_dev *dev)
1633{
1634 u8 hdr_type;
1635
1636#ifdef CONFIG_PCI_IOV
1637 if (dev->is_virtfn)
1638 return dev->physfn->sriov->hdr_type;
1639#endif
1640 pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type);
1641 return hdr_type;
1642}
1643
1644#define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
1645
1646static void pci_msi_setup_pci_dev(struct pci_dev *dev)
1647{
1648 /*
1649 * Disable the MSI hardware to avoid screaming interrupts
1650 * during boot. This is the power on reset default so
1651 * usually this should be a noop.
1652 */
1653 dev->msi_cap = pci_find_capability(dev, PCI_CAP_ID_MSI);
1654 if (dev->msi_cap)
1655 pci_msi_set_enable(dev, 0);
1656
1657 dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX);
1658 if (dev->msix_cap)
1659 pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
1660}
1661
1662/**
1663 * pci_intx_mask_broken - Test PCI_COMMAND_INTX_DISABLE writability
1664 * @dev: PCI device
1665 *
1666 * Test whether PCI_COMMAND_INTX_DISABLE is writable for @dev. Check this
1667 * at enumeration-time to avoid modifying PCI_COMMAND at run-time.
1668 */
1669static int pci_intx_mask_broken(struct pci_dev *dev)
1670{
1671 u16 orig, toggle, new;
1672
1673 pci_read_config_word(dev, PCI_COMMAND, &orig);
1674 toggle = orig ^ PCI_COMMAND_INTX_DISABLE;
1675 pci_write_config_word(dev, PCI_COMMAND, toggle);
1676 pci_read_config_word(dev, PCI_COMMAND, &new);
1677
1678 pci_write_config_word(dev, PCI_COMMAND, orig);
1679
1680 /*
1681 * PCI_COMMAND_INTX_DISABLE was reserved and read-only prior to PCI
1682 * r2.3, so strictly speaking, a device is not *broken* if it's not
1683 * writable. But we'll live with the misnomer for now.
1684 */
1685 if (new != toggle)
1686 return 1;
1687 return 0;
1688}
1689
1690static void early_dump_pci_device(struct pci_dev *pdev)
1691{
1692 u32 value[256 / 4];
1693 int i;
1694
1695 pci_info(pdev, "config space:\n");
1696
1697 for (i = 0; i < 256; i += 4)
1698 pci_read_config_dword(pdev, i, &value[i / 4]);
1699
1700 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 1,
1701 value, 256, false);
1702}
1703
1704/**
1705 * pci_setup_device - Fill in class and map information of a device
1706 * @dev: the device structure to fill
1707 *
1708 * Initialize the device structure with information about the device's
1709 * vendor,class,memory and IO-space addresses, IRQ lines etc.
1710 * Called at initialisation of the PCI subsystem and by CardBus services.
1711 * Returns 0 on success and negative if unknown type of device (not normal,
1712 * bridge or CardBus).
1713 */
1714int pci_setup_device(struct pci_dev *dev)
1715{
1716 u32 class;
1717 u16 cmd;
1718 u8 hdr_type;
1719 int pos = 0;
1720 struct pci_bus_region region;
1721 struct resource *res;
1722
1723 hdr_type = pci_hdr_type(dev);
1724
1725 dev->sysdata = dev->bus->sysdata;
1726 dev->dev.parent = dev->bus->bridge;
1727 dev->dev.bus = &pci_bus_type;
1728 dev->hdr_type = hdr_type & 0x7f;
1729 dev->multifunction = !!(hdr_type & 0x80);
1730 dev->error_state = pci_channel_io_normal;
1731 set_pcie_port_type(dev);
1732
1733 pci_dev_assign_slot(dev);
1734
1735 /*
1736 * Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
1737 * set this higher, assuming the system even supports it.
1738 */
1739 dev->dma_mask = 0xffffffff;
1740
1741 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
1742 dev->bus->number, PCI_SLOT(dev->devfn),
1743 PCI_FUNC(dev->devfn));
1744
1745 class = pci_class(dev);
1746
1747 dev->revision = class & 0xff;
1748 dev->class = class >> 8; /* upper 3 bytes */
1749
1750 pci_info(dev, "[%04x:%04x] type %02x class %#08x\n",
1751 dev->vendor, dev->device, dev->hdr_type, dev->class);
1752
1753 if (pci_early_dump)
1754 early_dump_pci_device(dev);
1755
1756 /* Need to have dev->class ready */
1757 dev->cfg_size = pci_cfg_space_size(dev);
1758
1759 /* Need to have dev->cfg_size ready */
1760 set_pcie_thunderbolt(dev);
1761
1762 set_pcie_untrusted(dev);
1763
1764 /* "Unknown power state" */
1765 dev->current_state = PCI_UNKNOWN;
1766
1767 /* Early fixups, before probing the BARs */
1768 pci_fixup_device(pci_fixup_early, dev);
1769
1770 /* Device class may be changed after fixup */
1771 class = dev->class >> 8;
1772
1773 if (dev->non_compliant_bars) {
1774 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1775 if (cmd & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) {
1776 pci_info(dev, "device has non-compliant BARs; disabling IO/MEM decoding\n");
1777 cmd &= ~PCI_COMMAND_IO;
1778 cmd &= ~PCI_COMMAND_MEMORY;
1779 pci_write_config_word(dev, PCI_COMMAND, cmd);
1780 }
1781 }
1782
1783 dev->broken_intx_masking = pci_intx_mask_broken(dev);
1784
1785 switch (dev->hdr_type) { /* header type */
1786 case PCI_HEADER_TYPE_NORMAL: /* standard header */
1787 if (class == PCI_CLASS_BRIDGE_PCI)
1788 goto bad;
1789 pci_read_irq(dev);
1790 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1791
1792 pci_subsystem_ids(dev, &dev->subsystem_vendor, &dev->subsystem_device);
1793
1794 /*
1795 * Do the ugly legacy mode stuff here rather than broken chip
1796 * quirk code. Legacy mode ATA controllers have fixed
1797 * addresses. These are not always echoed in BAR0-3, and
1798 * BAR0-3 in a few cases contain junk!
1799 */
1800 if (class == PCI_CLASS_STORAGE_IDE) {
1801 u8 progif;
1802 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1803 if ((progif & 1) == 0) {
1804 region.start = 0x1F0;
1805 region.end = 0x1F7;
1806 res = &dev->resource[0];
1807 res->flags = LEGACY_IO_RESOURCE;
1808 pcibios_bus_to_resource(dev->bus, res, ®ion);
1809 pci_info(dev, "legacy IDE quirk: reg 0x10: %pR\n",
1810 res);
1811 region.start = 0x3F6;
1812 region.end = 0x3F6;
1813 res = &dev->resource[1];
1814 res->flags = LEGACY_IO_RESOURCE;
1815 pcibios_bus_to_resource(dev->bus, res, ®ion);
1816 pci_info(dev, "legacy IDE quirk: reg 0x14: %pR\n",
1817 res);
1818 }
1819 if ((progif & 4) == 0) {
1820 region.start = 0x170;
1821 region.end = 0x177;
1822 res = &dev->resource[2];
1823 res->flags = LEGACY_IO_RESOURCE;
1824 pcibios_bus_to_resource(dev->bus, res, ®ion);
1825 pci_info(dev, "legacy IDE quirk: reg 0x18: %pR\n",
1826 res);
1827 region.start = 0x376;
1828 region.end = 0x376;
1829 res = &dev->resource[3];
1830 res->flags = LEGACY_IO_RESOURCE;
1831 pcibios_bus_to_resource(dev->bus, res, ®ion);
1832 pci_info(dev, "legacy IDE quirk: reg 0x1c: %pR\n",
1833 res);
1834 }
1835 }
1836 break;
1837
1838 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1839 /*
1840 * The PCI-to-PCI bridge spec requires that subtractive
1841 * decoding (i.e. transparent) bridge must have programming
1842 * interface code of 0x01.
1843 */
1844 pci_read_irq(dev);
1845 dev->transparent = ((dev->class & 0xff) == 1);
1846 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1847 pci_read_bridge_windows(dev);
1848 set_pcie_hotplug_bridge(dev);
1849 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1850 if (pos) {
1851 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1852 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1853 }
1854 break;
1855
1856 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1857 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1858 goto bad;
1859 pci_read_irq(dev);
1860 pci_read_bases(dev, 1, 0);
1861 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1862 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1863 break;
1864
1865 default: /* unknown header */
1866 pci_err(dev, "unknown header type %02x, ignoring device\n",
1867 dev->hdr_type);
1868 return -EIO;
1869
1870 bad:
1871 pci_err(dev, "ignoring class %#08x (doesn't match header type %02x)\n",
1872 dev->class, dev->hdr_type);
1873 dev->class = PCI_CLASS_NOT_DEFINED << 8;
1874 }
1875
1876 /* We found a fine healthy device, go go go... */
1877 return 0;
1878}
1879
1880static void pci_configure_mps(struct pci_dev *dev)
1881{
1882 struct pci_dev *bridge = pci_upstream_bridge(dev);
1883 int mps, mpss, p_mps, rc;
1884
1885 if (!pci_is_pcie(dev) || !bridge || !pci_is_pcie(bridge))
1886 return;
1887
1888 /* MPS and MRRS fields are of type 'RsvdP' for VFs, short-circuit out */
1889 if (dev->is_virtfn)
1890 return;
1891
1892 mps = pcie_get_mps(dev);
1893 p_mps = pcie_get_mps(bridge);
1894
1895 if (mps == p_mps)
1896 return;
1897
1898 if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
1899 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",
1900 mps, pci_name(bridge), p_mps);
1901 return;
1902 }
1903
1904 /*
1905 * Fancier MPS configuration is done later by
1906 * pcie_bus_configure_settings()
1907 */
1908 if (pcie_bus_config != PCIE_BUS_DEFAULT)
1909 return;
1910
1911 mpss = 128 << dev->pcie_mpss;
1912 if (mpss < p_mps && pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT) {
1913 pcie_set_mps(bridge, mpss);
1914 pci_info(dev, "Upstream bridge's Max Payload Size set to %d (was %d, max %d)\n",
1915 mpss, p_mps, 128 << bridge->pcie_mpss);
1916 p_mps = pcie_get_mps(bridge);
1917 }
1918
1919 rc = pcie_set_mps(dev, p_mps);
1920 if (rc) {
1921 pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
1922 p_mps);
1923 return;
1924 }
1925
1926 pci_info(dev, "Max Payload Size set to %d (was %d, max %d)\n",
1927 p_mps, mps, mpss);
1928}
1929
1930int pci_configure_extended_tags(struct pci_dev *dev, void *ign)
1931{
1932 struct pci_host_bridge *host;
1933 u32 cap;
1934 u16 ctl;
1935 int ret;
1936
1937 if (!pci_is_pcie(dev))
1938 return 0;
1939
1940 ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap);
1941 if (ret)
1942 return 0;
1943
1944 if (!(cap & PCI_EXP_DEVCAP_EXT_TAG))
1945 return 0;
1946
1947 ret = pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
1948 if (ret)
1949 return 0;
1950
1951 host = pci_find_host_bridge(dev->bus);
1952 if (!host)
1953 return 0;
1954
1955 /*
1956 * If some device in the hierarchy doesn't handle Extended Tags
1957 * correctly, make sure they're disabled.
1958 */
1959 if (host->no_ext_tags) {
1960 if (ctl & PCI_EXP_DEVCTL_EXT_TAG) {
1961 pci_info(dev, "disabling Extended Tags\n");
1962 pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
1963 PCI_EXP_DEVCTL_EXT_TAG);
1964 }
1965 return 0;
1966 }
1967
1968 if (!(ctl & PCI_EXP_DEVCTL_EXT_TAG)) {
1969 pci_info(dev, "enabling Extended Tags\n");
1970 pcie_capability_set_word(dev, PCI_EXP_DEVCTL,
1971 PCI_EXP_DEVCTL_EXT_TAG);
1972 }
1973 return 0;
1974}
1975
1976/**
1977 * pcie_relaxed_ordering_enabled - Probe for PCIe relaxed ordering enable
1978 * @dev: PCI device to query
1979 *
1980 * Returns true if the device has enabled relaxed ordering attribute.
1981 */
1982bool pcie_relaxed_ordering_enabled(struct pci_dev *dev)
1983{
1984 u16 v;
1985
1986 pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &v);
1987
1988 return !!(v & PCI_EXP_DEVCTL_RELAX_EN);
1989}
1990EXPORT_SYMBOL(pcie_relaxed_ordering_enabled);
1991
1992static void pci_configure_relaxed_ordering(struct pci_dev *dev)
1993{
1994 struct pci_dev *root;
1995
1996 /* PCI_EXP_DEVICE_RELAX_EN is RsvdP in VFs */
1997 if (dev->is_virtfn)
1998 return;
1999
2000 if (!pcie_relaxed_ordering_enabled(dev))
2001 return;
2002
2003 /*
2004 * For now, we only deal with Relaxed Ordering issues with Root
2005 * Ports. Peer-to-Peer DMA is another can of worms.
2006 */
2007 root = pci_find_pcie_root_port(dev);
2008 if (!root)
2009 return;
2010
2011 if (root->dev_flags & PCI_DEV_FLAGS_NO_RELAXED_ORDERING) {
2012 pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
2013 PCI_EXP_DEVCTL_RELAX_EN);
2014 pci_info(dev, "Relaxed Ordering disabled because the Root Port didn't support it\n");
2015 }
2016}
2017
2018static void pci_configure_ltr(struct pci_dev *dev)
2019{
2020#ifdef CONFIG_PCIEASPM
2021 struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
2022 struct pci_dev *bridge;
2023 u32 cap, ctl;
2024
2025 if (!pci_is_pcie(dev))
2026 return;
2027
2028 pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
2029 if (!(cap & PCI_EXP_DEVCAP2_LTR))
2030 return;
2031
2032 pcie_capability_read_dword(dev, PCI_EXP_DEVCTL2, &ctl);
2033 if (ctl & PCI_EXP_DEVCTL2_LTR_EN) {
2034 if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
2035 dev->ltr_path = 1;
2036 return;
2037 }
2038
2039 bridge = pci_upstream_bridge(dev);
2040 if (bridge && bridge->ltr_path)
2041 dev->ltr_path = 1;
2042
2043 return;
2044 }
2045
2046 if (!host->native_ltr)
2047 return;
2048
2049 /*
2050 * Software must not enable LTR in an Endpoint unless the Root
2051 * Complex and all intermediate Switches indicate support for LTR.
2052 * PCIe r4.0, sec 6.18.
2053 */
2054 if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT ||
2055 ((bridge = pci_upstream_bridge(dev)) &&
2056 bridge->ltr_path)) {
2057 pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
2058 PCI_EXP_DEVCTL2_LTR_EN);
2059 dev->ltr_path = 1;
2060 }
2061#endif
2062}
2063
2064static void pci_configure_eetlp_prefix(struct pci_dev *dev)
2065{
2066#ifdef CONFIG_PCI_PASID
2067 struct pci_dev *bridge;
2068 int pcie_type;
2069 u32 cap;
2070
2071 if (!pci_is_pcie(dev))
2072 return;
2073
2074 pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
2075 if (!(cap & PCI_EXP_DEVCAP2_EE_PREFIX))
2076 return;
2077
2078 pcie_type = pci_pcie_type(dev);
2079 if (pcie_type == PCI_EXP_TYPE_ROOT_PORT ||
2080 pcie_type == PCI_EXP_TYPE_RC_END)
2081 dev->eetlp_prefix_path = 1;
2082 else {
2083 bridge = pci_upstream_bridge(dev);
2084 if (bridge && bridge->eetlp_prefix_path)
2085 dev->eetlp_prefix_path = 1;
2086 }
2087#endif
2088}
2089
2090static void pci_configure_serr(struct pci_dev *dev)
2091{
2092 u16 control;
2093
2094 if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
2095
2096 /*
2097 * A bridge will not forward ERR_ messages coming from an
2098 * endpoint unless SERR# forwarding is enabled.
2099 */
2100 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &control);
2101 if (!(control & PCI_BRIDGE_CTL_SERR)) {
2102 control |= PCI_BRIDGE_CTL_SERR;
2103 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, control);
2104 }
2105 }
2106}
2107
2108static void pci_configure_device(struct pci_dev *dev)
2109{
2110 pci_configure_mps(dev);
2111 pci_configure_extended_tags(dev, NULL);
2112 pci_configure_relaxed_ordering(dev);
2113 pci_configure_ltr(dev);
2114 pci_configure_eetlp_prefix(dev);
2115 pci_configure_serr(dev);
2116
2117 pci_acpi_program_hp_params(dev);
2118}
2119
2120static void pci_release_capabilities(struct pci_dev *dev)
2121{
2122 pci_aer_exit(dev);
2123 pci_vpd_release(dev);
2124 pci_iov_release(dev);
2125 pci_free_cap_save_buffers(dev);
2126}
2127
2128/**
2129 * pci_release_dev - Free a PCI device structure when all users of it are
2130 * finished
2131 * @dev: device that's been disconnected
2132 *
2133 * Will be called only by the device core when all users of this PCI device are
2134 * done.
2135 */
2136static void pci_release_dev(struct device *dev)
2137{
2138 struct pci_dev *pci_dev;
2139
2140 pci_dev = to_pci_dev(dev);
2141 pci_release_capabilities(pci_dev);
2142 pci_release_of_node(pci_dev);
2143 pcibios_release_device(pci_dev);
2144 pci_bus_put(pci_dev->bus);
2145 kfree(pci_dev->driver_override);
2146 bitmap_free(pci_dev->dma_alias_mask);
2147 kfree(pci_dev);
2148}
2149
2150struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
2151{
2152 struct pci_dev *dev;
2153
2154 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
2155 if (!dev)
2156 return NULL;
2157
2158 INIT_LIST_HEAD(&dev->bus_list);
2159 dev->dev.type = &pci_dev_type;
2160 dev->bus = pci_bus_get(bus);
2161
2162 return dev;
2163}
2164EXPORT_SYMBOL(pci_alloc_dev);
2165
2166static bool pci_bus_crs_vendor_id(u32 l)
2167{
2168 return (l & 0xffff) == 0x0001;
2169}
2170
2171static bool pci_bus_wait_crs(struct pci_bus *bus, int devfn, u32 *l,
2172 int timeout)
2173{
2174 int delay = 1;
2175
2176 if (!pci_bus_crs_vendor_id(*l))
2177 return true; /* not a CRS completion */
2178
2179 if (!timeout)
2180 return false; /* CRS, but caller doesn't want to wait */
2181
2182 /*
2183 * We got the reserved Vendor ID that indicates a completion with
2184 * Configuration Request Retry Status (CRS). Retry until we get a
2185 * valid Vendor ID or we time out.
2186 */
2187 while (pci_bus_crs_vendor_id(*l)) {
2188 if (delay > timeout) {
2189 pr_warn("pci %04x:%02x:%02x.%d: not ready after %dms; giving up\n",
2190 pci_domain_nr(bus), bus->number,
2191 PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2192
2193 return false;
2194 }
2195 if (delay >= 1000)
2196 pr_info("pci %04x:%02x:%02x.%d: not ready after %dms; waiting\n",
2197 pci_domain_nr(bus), bus->number,
2198 PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2199
2200 msleep(delay);
2201 delay *= 2;
2202
2203 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
2204 return false;
2205 }
2206
2207 if (delay >= 1000)
2208 pr_info("pci %04x:%02x:%02x.%d: ready after %dms\n",
2209 pci_domain_nr(bus), bus->number,
2210 PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2211
2212 return true;
2213}
2214
2215bool pci_bus_generic_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
2216 int timeout)
2217{
2218 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
2219 return false;
2220
2221 /* Some broken boards return 0 or ~0 if a slot is empty: */
2222 if (*l == 0xffffffff || *l == 0x00000000 ||
2223 *l == 0x0000ffff || *l == 0xffff0000)
2224 return false;
2225
2226 if (pci_bus_crs_vendor_id(*l))
2227 return pci_bus_wait_crs(bus, devfn, l, timeout);
2228
2229 return true;
2230}
2231
2232bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
2233 int timeout)
2234{
2235#ifdef CONFIG_PCI_QUIRKS
2236 struct pci_dev *bridge = bus->self;
2237
2238 /*
2239 * Certain IDT switches have an issue where they improperly trigger
2240 * ACS Source Validation errors on completions for config reads.
2241 */
2242 if (bridge && bridge->vendor == PCI_VENDOR_ID_IDT &&
2243 bridge->device == 0x80b5)
2244 return pci_idt_bus_quirk(bus, devfn, l, timeout);
2245#endif
2246
2247 return pci_bus_generic_read_dev_vendor_id(bus, devfn, l, timeout);
2248}
2249EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
2250
2251/*
2252 * Read the config data for a PCI device, sanity-check it,
2253 * and fill in the dev structure.
2254 */
2255static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
2256{
2257 struct pci_dev *dev;
2258 u32 l;
2259
2260 if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
2261 return NULL;
2262
2263 dev = pci_alloc_dev(bus);
2264 if (!dev)
2265 return NULL;
2266
2267 dev->devfn = devfn;
2268 dev->vendor = l & 0xffff;
2269 dev->device = (l >> 16) & 0xffff;
2270
2271 pci_set_of_node(dev);
2272
2273 if (pci_setup_device(dev)) {
2274 pci_bus_put(dev->bus);
2275 kfree(dev);
2276 return NULL;
2277 }
2278
2279 return dev;
2280}
2281
2282void pcie_report_downtraining(struct pci_dev *dev)
2283{
2284 if (!pci_is_pcie(dev))
2285 return;
2286
2287 /* Look from the device up to avoid downstream ports with no devices */
2288 if ((pci_pcie_type(dev) != PCI_EXP_TYPE_ENDPOINT) &&
2289 (pci_pcie_type(dev) != PCI_EXP_TYPE_LEG_END) &&
2290 (pci_pcie_type(dev) != PCI_EXP_TYPE_UPSTREAM))
2291 return;
2292
2293 /* Multi-function PCIe devices share the same link/status */
2294 if (PCI_FUNC(dev->devfn) != 0 || dev->is_virtfn)
2295 return;
2296
2297 /* Print link status only if the device is constrained by the fabric */
2298 __pcie_print_link_status(dev, false);
2299}
2300
2301static void pci_init_capabilities(struct pci_dev *dev)
2302{
2303 /* Enhanced Allocation */
2304 pci_ea_init(dev);
2305
2306 /* Setup MSI caps & disable MSI/MSI-X interrupts */
2307 pci_msi_setup_pci_dev(dev);
2308
2309 /* Buffers for saving PCIe and PCI-X capabilities */
2310 pci_allocate_cap_save_buffers(dev);
2311
2312 /* Power Management */
2313 pci_pm_init(dev);
2314
2315 /* Vital Product Data */
2316 pci_vpd_init(dev);
2317
2318 /* Alternative Routing-ID Forwarding */
2319 pci_configure_ari(dev);
2320
2321 /* Single Root I/O Virtualization */
2322 pci_iov_init(dev);
2323
2324 /* Address Translation Services */
2325 pci_ats_init(dev);
2326
2327 /* Enable ACS P2P upstream forwarding */
2328 pci_enable_acs(dev);
2329
2330 /* Precision Time Measurement */
2331 pci_ptm_init(dev);
2332
2333 /* Advanced Error Reporting */
2334 pci_aer_init(dev);
2335
2336 pcie_report_downtraining(dev);
2337
2338 if (pci_probe_reset_function(dev) == 0)
2339 dev->reset_fn = 1;
2340}
2341
2342/*
2343 * This is the equivalent of pci_host_bridge_msi_domain() that acts on
2344 * devices. Firmware interfaces that can select the MSI domain on a
2345 * per-device basis should be called from here.
2346 */
2347static struct irq_domain *pci_dev_msi_domain(struct pci_dev *dev)
2348{
2349 struct irq_domain *d;
2350
2351 /*
2352 * If a domain has been set through the pcibios_add_device()
2353 * callback, then this is the one (platform code knows best).
2354 */
2355 d = dev_get_msi_domain(&dev->dev);
2356 if (d)
2357 return d;
2358
2359 /*
2360 * Let's see if we have a firmware interface able to provide
2361 * the domain.
2362 */
2363 d = pci_msi_get_device_domain(dev);
2364 if (d)
2365 return d;
2366
2367 return NULL;
2368}
2369
2370static void pci_set_msi_domain(struct pci_dev *dev)
2371{
2372 struct irq_domain *d;
2373
2374 /*
2375 * If the platform or firmware interfaces cannot supply a
2376 * device-specific MSI domain, then inherit the default domain
2377 * from the host bridge itself.
2378 */
2379 d = pci_dev_msi_domain(dev);
2380 if (!d)
2381 d = dev_get_msi_domain(&dev->bus->dev);
2382
2383 dev_set_msi_domain(&dev->dev, d);
2384}
2385
2386void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
2387{
2388 int ret;
2389
2390 pci_configure_device(dev);
2391
2392 device_initialize(&dev->dev);
2393 dev->dev.release = pci_release_dev;
2394
2395 set_dev_node(&dev->dev, pcibus_to_node(bus));
2396 dev->dev.dma_mask = &dev->dma_mask;
2397 dev->dev.dma_parms = &dev->dma_parms;
2398 dev->dev.coherent_dma_mask = 0xffffffffull;
2399
2400 dma_set_max_seg_size(&dev->dev, 65536);
2401 dma_set_seg_boundary(&dev->dev, 0xffffffff);
2402
2403 /* Fix up broken headers */
2404 pci_fixup_device(pci_fixup_header, dev);
2405
2406 /* Moved out from quirk header fixup code */
2407 pci_reassigndev_resource_alignment(dev);
2408
2409 /* Clear the state_saved flag */
2410 dev->state_saved = false;
2411
2412 /* Initialize various capabilities */
2413 pci_init_capabilities(dev);
2414
2415 /*
2416 * Add the device to our list of discovered devices
2417 * and the bus list for fixup functions, etc.
2418 */
2419 down_write(&pci_bus_sem);
2420 list_add_tail(&dev->bus_list, &bus->devices);
2421 up_write(&pci_bus_sem);
2422
2423 ret = pcibios_add_device(dev);
2424 WARN_ON(ret < 0);
2425
2426 /* Set up MSI IRQ domain */
2427 pci_set_msi_domain(dev);
2428
2429 /* Notifier could use PCI capabilities */
2430 dev->match_driver = false;
2431 ret = device_add(&dev->dev);
2432 WARN_ON(ret < 0);
2433}
2434
2435struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn)
2436{
2437 struct pci_dev *dev;
2438
2439 dev = pci_get_slot(bus, devfn);
2440 if (dev) {
2441 pci_dev_put(dev);
2442 return dev;
2443 }
2444
2445 dev = pci_scan_device(bus, devfn);
2446 if (!dev)
2447 return NULL;
2448
2449 pci_device_add(dev, bus);
2450
2451 return dev;
2452}
2453EXPORT_SYMBOL(pci_scan_single_device);
2454
2455static unsigned next_fn(struct pci_bus *bus, struct pci_dev *dev, unsigned fn)
2456{
2457 int pos;
2458 u16 cap = 0;
2459 unsigned next_fn;
2460
2461 if (pci_ari_enabled(bus)) {
2462 if (!dev)
2463 return 0;
2464 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
2465 if (!pos)
2466 return 0;
2467
2468 pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap);
2469 next_fn = PCI_ARI_CAP_NFN(cap);
2470 if (next_fn <= fn)
2471 return 0; /* protect against malformed list */
2472
2473 return next_fn;
2474 }
2475
2476 /* dev may be NULL for non-contiguous multifunction devices */
2477 if (!dev || dev->multifunction)
2478 return (fn + 1) % 8;
2479
2480 return 0;
2481}
2482
2483static int only_one_child(struct pci_bus *bus)
2484{
2485 struct pci_dev *bridge = bus->self;
2486
2487 /*
2488 * Systems with unusual topologies set PCI_SCAN_ALL_PCIE_DEVS so
2489 * we scan for all possible devices, not just Device 0.
2490 */
2491 if (pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
2492 return 0;
2493
2494 /*
2495 * A PCIe Downstream Port normally leads to a Link with only Device
2496 * 0 on it (PCIe spec r3.1, sec 7.3.1). As an optimization, scan
2497 * only for Device 0 in that situation.
2498 */
2499 if (bridge && pci_is_pcie(bridge) && pcie_downstream_port(bridge))
2500 return 1;
2501
2502 return 0;
2503}
2504
2505/**
2506 * pci_scan_slot - Scan a PCI slot on a bus for devices
2507 * @bus: PCI bus to scan
2508 * @devfn: slot number to scan (must have zero function)
2509 *
2510 * Scan a PCI slot on the specified PCI bus for devices, adding
2511 * discovered devices to the @bus->devices list. New devices
2512 * will not have is_added set.
2513 *
2514 * Returns the number of new devices found.
2515 */
2516int pci_scan_slot(struct pci_bus *bus, int devfn)
2517{
2518 unsigned fn, nr = 0;
2519 struct pci_dev *dev;
2520
2521 if (only_one_child(bus) && (devfn > 0))
2522 return 0; /* Already scanned the entire slot */
2523
2524 dev = pci_scan_single_device(bus, devfn);
2525 if (!dev)
2526 return 0;
2527 if (!pci_dev_is_added(dev))
2528 nr++;
2529
2530 for (fn = next_fn(bus, dev, 0); fn > 0; fn = next_fn(bus, dev, fn)) {
2531 dev = pci_scan_single_device(bus, devfn + fn);
2532 if (dev) {
2533 if (!pci_dev_is_added(dev))
2534 nr++;
2535 dev->multifunction = 1;
2536 }
2537 }
2538
2539 /* Only one slot has PCIe device */
2540 if (bus->self && nr)
2541 pcie_aspm_init_link_state(bus->self);
2542
2543 return nr;
2544}
2545EXPORT_SYMBOL(pci_scan_slot);
2546
2547static int pcie_find_smpss(struct pci_dev *dev, void *data)
2548{
2549 u8 *smpss = data;
2550
2551 if (!pci_is_pcie(dev))
2552 return 0;
2553
2554 /*
2555 * We don't have a way to change MPS settings on devices that have
2556 * drivers attached. A hot-added device might support only the minimum
2557 * MPS setting (MPS=128). Therefore, if the fabric contains a bridge
2558 * where devices may be hot-added, we limit the fabric MPS to 128 so
2559 * hot-added devices will work correctly.
2560 *
2561 * However, if we hot-add a device to a slot directly below a Root
2562 * Port, it's impossible for there to be other existing devices below
2563 * the port. We don't limit the MPS in this case because we can
2564 * reconfigure MPS on both the Root Port and the hot-added device,
2565 * and there are no other devices involved.
2566 *
2567 * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
2568 */
2569 if (dev->is_hotplug_bridge &&
2570 pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
2571 *smpss = 0;
2572
2573 if (*smpss > dev->pcie_mpss)
2574 *smpss = dev->pcie_mpss;
2575
2576 return 0;
2577}
2578
2579static void pcie_write_mps(struct pci_dev *dev, int mps)
2580{
2581 int rc;
2582
2583 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
2584 mps = 128 << dev->pcie_mpss;
2585
2586 if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
2587 dev->bus->self)
2588
2589 /*
2590 * For "Performance", the assumption is made that
2591 * downstream communication will never be larger than
2592 * the MRRS. So, the MPS only needs to be configured
2593 * for the upstream communication. This being the case,
2594 * walk from the top down and set the MPS of the child
2595 * to that of the parent bus.
2596 *
2597 * Configure the device MPS with the smaller of the
2598 * device MPSS or the bridge MPS (which is assumed to be
2599 * properly configured at this point to the largest
2600 * allowable MPS based on its parent bus).
2601 */
2602 mps = min(mps, pcie_get_mps(dev->bus->self));
2603 }
2604
2605 rc = pcie_set_mps(dev, mps);
2606 if (rc)
2607 pci_err(dev, "Failed attempting to set the MPS\n");
2608}
2609
2610static void pcie_write_mrrs(struct pci_dev *dev)
2611{
2612 int rc, mrrs;
2613
2614 /*
2615 * In the "safe" case, do not configure the MRRS. There appear to be
2616 * issues with setting MRRS to 0 on a number of devices.
2617 */
2618 if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
2619 return;
2620
2621 /*
2622 * For max performance, the MRRS must be set to the largest supported
2623 * value. However, it cannot be configured larger than the MPS the
2624 * device or the bus can support. This should already be properly
2625 * configured by a prior call to pcie_write_mps().
2626 */
2627 mrrs = pcie_get_mps(dev);
2628
2629 /*
2630 * MRRS is a R/W register. Invalid values can be written, but a
2631 * subsequent read will verify if the value is acceptable or not.
2632 * If the MRRS value provided is not acceptable (e.g., too large),
2633 * shrink the value until it is acceptable to the HW.
2634 */
2635 while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
2636 rc = pcie_set_readrq(dev, mrrs);
2637 if (!rc)
2638 break;
2639
2640 pci_warn(dev, "Failed attempting to set the MRRS\n");
2641 mrrs /= 2;
2642 }
2643
2644 if (mrrs < 128)
2645 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");
2646}
2647
2648static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
2649{
2650 int mps, orig_mps;
2651
2652 if (!pci_is_pcie(dev))
2653 return 0;
2654
2655 if (pcie_bus_config == PCIE_BUS_TUNE_OFF ||
2656 pcie_bus_config == PCIE_BUS_DEFAULT)
2657 return 0;
2658
2659 mps = 128 << *(u8 *)data;
2660 orig_mps = pcie_get_mps(dev);
2661
2662 pcie_write_mps(dev, mps);
2663 pcie_write_mrrs(dev);
2664
2665 pci_info(dev, "Max Payload Size set to %4d/%4d (was %4d), Max Read Rq %4d\n",
2666 pcie_get_mps(dev), 128 << dev->pcie_mpss,
2667 orig_mps, pcie_get_readrq(dev));
2668
2669 return 0;
2670}
2671
2672/*
2673 * pcie_bus_configure_settings() requires that pci_walk_bus work in a top-down,
2674 * parents then children fashion. If this changes, then this code will not
2675 * work as designed.
2676 */
2677void pcie_bus_configure_settings(struct pci_bus *bus)
2678{
2679 u8 smpss = 0;
2680
2681 if (!bus->self)
2682 return;
2683
2684 if (!pci_is_pcie(bus->self))
2685 return;
2686
2687 /*
2688 * FIXME - Peer to peer DMA is possible, though the endpoint would need
2689 * to be aware of the MPS of the destination. To work around this,
2690 * simply force the MPS of the entire system to the smallest possible.
2691 */
2692 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
2693 smpss = 0;
2694
2695 if (pcie_bus_config == PCIE_BUS_SAFE) {
2696 smpss = bus->self->pcie_mpss;
2697
2698 pcie_find_smpss(bus->self, &smpss);
2699 pci_walk_bus(bus, pcie_find_smpss, &smpss);
2700 }
2701
2702 pcie_bus_configure_set(bus->self, &smpss);
2703 pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
2704}
2705EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
2706
2707/*
2708 * Called after each bus is probed, but before its children are examined. This
2709 * is marked as __weak because multiple architectures define it.
2710 */
2711void __weak pcibios_fixup_bus(struct pci_bus *bus)
2712{
2713 /* nothing to do, expected to be removed in the future */
2714}
2715
2716/**
2717 * pci_scan_child_bus_extend() - Scan devices below a bus
2718 * @bus: Bus to scan for devices
2719 * @available_buses: Total number of buses available (%0 does not try to
2720 * extend beyond the minimal)
2721 *
2722 * Scans devices below @bus including subordinate buses. Returns new
2723 * subordinate number including all the found devices. Passing
2724 * @available_buses causes the remaining bus space to be distributed
2725 * equally between hotplug-capable bridges to allow future extension of the
2726 * hierarchy.
2727 */
2728static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
2729 unsigned int available_buses)
2730{
2731 unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0;
2732 unsigned int start = bus->busn_res.start;
2733 unsigned int devfn, fn, cmax, max = start;
2734 struct pci_dev *dev;
2735 int nr_devs;
2736
2737 dev_dbg(&bus->dev, "scanning bus\n");
2738
2739 /* Go find them, Rover! */
2740 for (devfn = 0; devfn < 256; devfn += 8) {
2741 nr_devs = pci_scan_slot(bus, devfn);
2742
2743 /*
2744 * The Jailhouse hypervisor may pass individual functions of a
2745 * multi-function device to a guest without passing function 0.
2746 * Look for them as well.
2747 */
2748 if (jailhouse_paravirt() && nr_devs == 0) {
2749 for (fn = 1; fn < 8; fn++) {
2750 dev = pci_scan_single_device(bus, devfn + fn);
2751 if (dev)
2752 dev->multifunction = 1;
2753 }
2754 }
2755 }
2756
2757 /* Reserve buses for SR-IOV capability */
2758 used_buses = pci_iov_bus_range(bus);
2759 max += used_buses;
2760
2761 /*
2762 * After performing arch-dependent fixup of the bus, look behind
2763 * all PCI-to-PCI bridges on this bus.
2764 */
2765 if (!bus->is_added) {
2766 dev_dbg(&bus->dev, "fixups for bus\n");
2767 pcibios_fixup_bus(bus);
2768 bus->is_added = 1;
2769 }
2770
2771 /*
2772 * Calculate how many hotplug bridges and normal bridges there
2773 * are on this bus. We will distribute the additional available
2774 * buses between hotplug bridges.
2775 */
2776 for_each_pci_bridge(dev, bus) {
2777 if (dev->is_hotplug_bridge)
2778 hotplug_bridges++;
2779 else
2780 normal_bridges++;
2781 }
2782
2783 /*
2784 * Scan bridges that are already configured. We don't touch them
2785 * unless they are misconfigured (which will be done in the second
2786 * scan below).
2787 */
2788 for_each_pci_bridge(dev, bus) {
2789 cmax = max;
2790 max = pci_scan_bridge_extend(bus, dev, max, 0, 0);
2791
2792 /*
2793 * Reserve one bus for each bridge now to avoid extending
2794 * hotplug bridges too much during the second scan below.
2795 */
2796 used_buses++;
2797 if (cmax - max > 1)
2798 used_buses += cmax - max - 1;
2799 }
2800
2801 /* Scan bridges that need to be reconfigured */
2802 for_each_pci_bridge(dev, bus) {
2803 unsigned int buses = 0;
2804
2805 if (!hotplug_bridges && normal_bridges == 1) {
2806
2807 /*
2808 * There is only one bridge on the bus (upstream
2809 * port) so it gets all available buses which it
2810 * can then distribute to the possible hotplug
2811 * bridges below.
2812 */
2813 buses = available_buses;
2814 } else if (dev->is_hotplug_bridge) {
2815
2816 /*
2817 * Distribute the extra buses between hotplug
2818 * bridges if any.
2819 */
2820 buses = available_buses / hotplug_bridges;
2821 buses = min(buses, available_buses - used_buses + 1);
2822 }
2823
2824 cmax = max;
2825 max = pci_scan_bridge_extend(bus, dev, cmax, buses, 1);
2826 /* One bus is already accounted so don't add it again */
2827 if (max - cmax > 1)
2828 used_buses += max - cmax - 1;
2829 }
2830
2831 /*
2832 * Make sure a hotplug bridge has at least the minimum requested
2833 * number of buses but allow it to grow up to the maximum available
2834 * bus number of there is room.
2835 */
2836 if (bus->self && bus->self->is_hotplug_bridge) {
2837 used_buses = max_t(unsigned int, available_buses,
2838 pci_hotplug_bus_size - 1);
2839 if (max - start < used_buses) {
2840 max = start + used_buses;
2841
2842 /* Do not allocate more buses than we have room left */
2843 if (max > bus->busn_res.end)
2844 max = bus->busn_res.end;
2845
2846 dev_dbg(&bus->dev, "%pR extended by %#02x\n",
2847 &bus->busn_res, max - start);
2848 }
2849 }
2850
2851 /*
2852 * We've scanned the bus and so we know all about what's on
2853 * the other side of any bridges that may be on this bus plus
2854 * any devices.
2855 *
2856 * Return how far we've got finding sub-buses.
2857 */
2858 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
2859 return max;
2860}
2861
2862/**
2863 * pci_scan_child_bus() - Scan devices below a bus
2864 * @bus: Bus to scan for devices
2865 *
2866 * Scans devices below @bus including subordinate buses. Returns new
2867 * subordinate number including all the found devices.
2868 */
2869unsigned int pci_scan_child_bus(struct pci_bus *bus)
2870{
2871 return pci_scan_child_bus_extend(bus, 0);
2872}
2873EXPORT_SYMBOL_GPL(pci_scan_child_bus);
2874
2875/**
2876 * pcibios_root_bridge_prepare - Platform-specific host bridge setup
2877 * @bridge: Host bridge to set up
2878 *
2879 * Default empty implementation. Replace with an architecture-specific setup
2880 * routine, if necessary.
2881 */
2882int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
2883{
2884 return 0;
2885}
2886
2887void __weak pcibios_add_bus(struct pci_bus *bus)
2888{
2889}
2890
2891void __weak pcibios_remove_bus(struct pci_bus *bus)
2892{
2893}
2894
2895struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
2896 struct pci_ops *ops, void *sysdata, struct list_head *resources)
2897{
2898 int error;
2899 struct pci_host_bridge *bridge;
2900
2901 bridge = pci_alloc_host_bridge(0);
2902 if (!bridge)
2903 return NULL;
2904
2905 bridge->dev.parent = parent;
2906
2907 list_splice_init(resources, &bridge->windows);
2908 bridge->sysdata = sysdata;
2909 bridge->busnr = bus;
2910 bridge->ops = ops;
2911
2912 error = pci_register_host_bridge(bridge);
2913 if (error < 0)
2914 goto err_out;
2915
2916 return bridge->bus;
2917
2918err_out:
2919 kfree(bridge);
2920 return NULL;
2921}
2922EXPORT_SYMBOL_GPL(pci_create_root_bus);
2923
2924int pci_host_probe(struct pci_host_bridge *bridge)
2925{
2926 struct pci_bus *bus, *child;
2927 int ret;
2928
2929 ret = pci_scan_root_bus_bridge(bridge);
2930 if (ret < 0) {
2931 dev_err(bridge->dev.parent, "Scanning root bridge failed");
2932 return ret;
2933 }
2934
2935 bus = bridge->bus;
2936
2937 /*
2938 * We insert PCI resources into the iomem_resource and
2939 * ioport_resource trees in either pci_bus_claim_resources()
2940 * or pci_bus_assign_resources().
2941 */
2942 if (pci_has_flag(PCI_PROBE_ONLY)) {
2943 pci_bus_claim_resources(bus);
2944 } else {
2945 pci_bus_size_bridges(bus);
2946 pci_bus_assign_resources(bus);
2947
2948 list_for_each_entry(child, &bus->children, node)
2949 pcie_bus_configure_settings(child);
2950 }
2951
2952 pci_bus_add_devices(bus);
2953 return 0;
2954}
2955EXPORT_SYMBOL_GPL(pci_host_probe);
2956
2957int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
2958{
2959 struct resource *res = &b->busn_res;
2960 struct resource *parent_res, *conflict;
2961
2962 res->start = bus;
2963 res->end = bus_max;
2964 res->flags = IORESOURCE_BUS;
2965
2966 if (!pci_is_root_bus(b))
2967 parent_res = &b->parent->busn_res;
2968 else {
2969 parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
2970 res->flags |= IORESOURCE_PCI_FIXED;
2971 }
2972
2973 conflict = request_resource_conflict(parent_res, res);
2974
2975 if (conflict)
2976 dev_info(&b->dev,
2977 "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
2978 res, pci_is_root_bus(b) ? "domain " : "",
2979 parent_res, conflict->name, conflict);
2980
2981 return conflict == NULL;
2982}
2983
2984int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
2985{
2986 struct resource *res = &b->busn_res;
2987 struct resource old_res = *res;
2988 resource_size_t size;
2989 int ret;
2990
2991 if (res->start > bus_max)
2992 return -EINVAL;
2993
2994 size = bus_max - res->start + 1;
2995 ret = adjust_resource(res, res->start, size);
2996 dev_info(&b->dev, "busn_res: %pR end %s updated to %02x\n",
2997 &old_res, ret ? "can not be" : "is", bus_max);
2998
2999 if (!ret && !res->parent)
3000 pci_bus_insert_busn_res(b, res->start, res->end);
3001
3002 return ret;
3003}
3004
3005void pci_bus_release_busn_res(struct pci_bus *b)
3006{
3007 struct resource *res = &b->busn_res;
3008 int ret;
3009
3010 if (!res->flags || !res->parent)
3011 return;
3012
3013 ret = release_resource(res);
3014 dev_info(&b->dev, "busn_res: %pR %s released\n",
3015 res, ret ? "can not be" : "is");
3016}
3017
3018int pci_scan_root_bus_bridge(struct pci_host_bridge *bridge)
3019{
3020 struct resource_entry *window;
3021 bool found = false;
3022 struct pci_bus *b;
3023 int max, bus, ret;
3024
3025 if (!bridge)
3026 return -EINVAL;
3027
3028 resource_list_for_each_entry(window, &bridge->windows)
3029 if (window->res->flags & IORESOURCE_BUS) {
3030 found = true;
3031 break;
3032 }
3033
3034 ret = pci_register_host_bridge(bridge);
3035 if (ret < 0)
3036 return ret;
3037
3038 b = bridge->bus;
3039 bus = bridge->busnr;
3040
3041 if (!found) {
3042 dev_info(&b->dev,
3043 "No busn resource found for root bus, will use [bus %02x-ff]\n",
3044 bus);
3045 pci_bus_insert_busn_res(b, bus, 255);
3046 }
3047
3048 max = pci_scan_child_bus(b);
3049
3050 if (!found)
3051 pci_bus_update_busn_res_end(b, max);
3052
3053 return 0;
3054}
3055EXPORT_SYMBOL(pci_scan_root_bus_bridge);
3056
3057struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
3058 struct pci_ops *ops, void *sysdata, struct list_head *resources)
3059{
3060 struct resource_entry *window;
3061 bool found = false;
3062 struct pci_bus *b;
3063 int max;
3064
3065 resource_list_for_each_entry(window, resources)
3066 if (window->res->flags & IORESOURCE_BUS) {
3067 found = true;
3068 break;
3069 }
3070
3071 b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
3072 if (!b)
3073 return NULL;
3074
3075 if (!found) {
3076 dev_info(&b->dev,
3077 "No busn resource found for root bus, will use [bus %02x-ff]\n",
3078 bus);
3079 pci_bus_insert_busn_res(b, bus, 255);
3080 }
3081
3082 max = pci_scan_child_bus(b);
3083
3084 if (!found)
3085 pci_bus_update_busn_res_end(b, max);
3086
3087 return b;
3088}
3089EXPORT_SYMBOL(pci_scan_root_bus);
3090
3091struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
3092 void *sysdata)
3093{
3094 LIST_HEAD(resources);
3095 struct pci_bus *b;
3096
3097 pci_add_resource(&resources, &ioport_resource);
3098 pci_add_resource(&resources, &iomem_resource);
3099 pci_add_resource(&resources, &busn_resource);
3100 b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
3101 if (b) {
3102 pci_scan_child_bus(b);
3103 } else {
3104 pci_free_resource_list(&resources);
3105 }
3106 return b;
3107}
3108EXPORT_SYMBOL(pci_scan_bus);
3109
3110/**
3111 * pci_rescan_bus_bridge_resize - Scan a PCI bus for devices
3112 * @bridge: PCI bridge for the bus to scan
3113 *
3114 * Scan a PCI bus and child buses for new devices, add them,
3115 * and enable them, resizing bridge mmio/io resource if necessary
3116 * and possible. The caller must ensure the child devices are already
3117 * removed for resizing to occur.
3118 *
3119 * Returns the max number of subordinate bus discovered.
3120 */
3121unsigned int pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
3122{
3123 unsigned int max;
3124 struct pci_bus *bus = bridge->subordinate;
3125
3126 max = pci_scan_child_bus(bus);
3127
3128 pci_assign_unassigned_bridge_resources(bridge);
3129
3130 pci_bus_add_devices(bus);
3131
3132 return max;
3133}
3134
3135/**
3136 * pci_rescan_bus - Scan a PCI bus for devices
3137 * @bus: PCI bus to scan
3138 *
3139 * Scan a PCI bus and child buses for new devices, add them,
3140 * and enable them.
3141 *
3142 * Returns the max number of subordinate bus discovered.
3143 */
3144unsigned int pci_rescan_bus(struct pci_bus *bus)
3145{
3146 unsigned int max;
3147
3148 max = pci_scan_child_bus(bus);
3149 pci_assign_unassigned_bus_resources(bus);
3150 pci_bus_add_devices(bus);
3151
3152 return max;
3153}
3154EXPORT_SYMBOL_GPL(pci_rescan_bus);
3155
3156/*
3157 * pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal
3158 * routines should always be executed under this mutex.
3159 */
3160static DEFINE_MUTEX(pci_rescan_remove_lock);
3161
3162void pci_lock_rescan_remove(void)
3163{
3164 mutex_lock(&pci_rescan_remove_lock);
3165}
3166EXPORT_SYMBOL_GPL(pci_lock_rescan_remove);
3167
3168void pci_unlock_rescan_remove(void)
3169{
3170 mutex_unlock(&pci_rescan_remove_lock);
3171}
3172EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove);
3173
3174static int __init pci_sort_bf_cmp(const struct device *d_a,
3175 const struct device *d_b)
3176{
3177 const struct pci_dev *a = to_pci_dev(d_a);
3178 const struct pci_dev *b = to_pci_dev(d_b);
3179
3180 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
3181 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
3182
3183 if (a->bus->number < b->bus->number) return -1;
3184 else if (a->bus->number > b->bus->number) return 1;
3185
3186 if (a->devfn < b->devfn) return -1;
3187 else if (a->devfn > b->devfn) return 1;
3188
3189 return 0;
3190}
3191
3192void __init pci_sort_breadthfirst(void)
3193{
3194 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);
3195}
3196
3197int pci_hp_add_bridge(struct pci_dev *dev)
3198{
3199 struct pci_bus *parent = dev->bus;
3200 int busnr, start = parent->busn_res.start;
3201 unsigned int available_buses = 0;
3202 int end = parent->busn_res.end;
3203
3204 for (busnr = start; busnr <= end; busnr++) {
3205 if (!pci_find_bus(pci_domain_nr(parent), busnr))
3206 break;
3207 }
3208 if (busnr-- > end) {
3209 pci_err(dev, "No bus number available for hot-added bridge\n");
3210 return -1;
3211 }
3212
3213 /* Scan bridges that are already configured */
3214 busnr = pci_scan_bridge(parent, dev, busnr, 0);
3215
3216 /*
3217 * Distribute the available bus numbers between hotplug-capable
3218 * bridges to make extending the chain later possible.
3219 */
3220 available_buses = end - busnr;
3221
3222 /* Scan bridges that need to be reconfigured */
3223 pci_scan_bridge_extend(parent, dev, busnr, available_buses, 1);
3224
3225 if (!dev->subordinate)
3226 return -1;
3227
3228 return 0;
3229}
3230EXPORT_SYMBOL_GPL(pci_hp_add_bridge);
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/of_device.h>
10#include <linux/of_pci.h>
11#include <linux/pci_hotplug.h>
12#include <linux/slab.h>
13#include <linux/module.h>
14#include <linux/cpumask.h>
15#include <linux/pci-aspm.h>
16#include <linux/aer.h>
17#include <linux/acpi.h>
18#include <linux/irqdomain.h>
19#include <linux/pm_runtime.h>
20#include "pci.h"
21
22#define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
23#define CARDBUS_RESERVE_BUSNR 3
24
25static struct resource busn_resource = {
26 .name = "PCI busn",
27 .start = 0,
28 .end = 255,
29 .flags = IORESOURCE_BUS,
30};
31
32/* Ugh. Need to stop exporting this to modules. */
33LIST_HEAD(pci_root_buses);
34EXPORT_SYMBOL(pci_root_buses);
35
36static LIST_HEAD(pci_domain_busn_res_list);
37
38struct pci_domain_busn_res {
39 struct list_head list;
40 struct resource res;
41 int domain_nr;
42};
43
44static struct resource *get_pci_domain_busn_res(int domain_nr)
45{
46 struct pci_domain_busn_res *r;
47
48 list_for_each_entry(r, &pci_domain_busn_res_list, list)
49 if (r->domain_nr == domain_nr)
50 return &r->res;
51
52 r = kzalloc(sizeof(*r), GFP_KERNEL);
53 if (!r)
54 return NULL;
55
56 r->domain_nr = domain_nr;
57 r->res.start = 0;
58 r->res.end = 0xff;
59 r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
60
61 list_add_tail(&r->list, &pci_domain_busn_res_list);
62
63 return &r->res;
64}
65
66static int find_anything(struct device *dev, void *data)
67{
68 return 1;
69}
70
71/*
72 * Some device drivers need know if pci is initiated.
73 * Basically, we think pci is not initiated when there
74 * is no device to be found on the pci_bus_type.
75 */
76int no_pci_devices(void)
77{
78 struct device *dev;
79 int no_devices;
80
81 dev = bus_find_device(&pci_bus_type, NULL, NULL, find_anything);
82 no_devices = (dev == NULL);
83 put_device(dev);
84 return no_devices;
85}
86EXPORT_SYMBOL(no_pci_devices);
87
88/*
89 * PCI Bus Class
90 */
91static void release_pcibus_dev(struct device *dev)
92{
93 struct pci_bus *pci_bus = to_pci_bus(dev);
94
95 put_device(pci_bus->bridge);
96 pci_bus_remove_resources(pci_bus);
97 pci_release_bus_of_node(pci_bus);
98 kfree(pci_bus);
99}
100
101static struct class pcibus_class = {
102 .name = "pci_bus",
103 .dev_release = &release_pcibus_dev,
104 .dev_groups = pcibus_groups,
105};
106
107static int __init pcibus_class_init(void)
108{
109 return class_register(&pcibus_class);
110}
111postcore_initcall(pcibus_class_init);
112
113static u64 pci_size(u64 base, u64 maxbase, u64 mask)
114{
115 u64 size = mask & maxbase; /* Find the significant bits */
116 if (!size)
117 return 0;
118
119 /* Get the lowest of them to find the decode size, and
120 from that the extent. */
121 size = (size & ~(size-1)) - 1;
122
123 /* base == maxbase can be valid only if the BAR has
124 already been programmed with all 1s. */
125 if (base == maxbase && ((base | size) & mask) != mask)
126 return 0;
127
128 return size;
129}
130
131static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
132{
133 u32 mem_type;
134 unsigned long flags;
135
136 if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
137 flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
138 flags |= IORESOURCE_IO;
139 return flags;
140 }
141
142 flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
143 flags |= IORESOURCE_MEM;
144 if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
145 flags |= IORESOURCE_PREFETCH;
146
147 mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
148 switch (mem_type) {
149 case PCI_BASE_ADDRESS_MEM_TYPE_32:
150 break;
151 case PCI_BASE_ADDRESS_MEM_TYPE_1M:
152 /* 1M mem BAR treated as 32-bit BAR */
153 break;
154 case PCI_BASE_ADDRESS_MEM_TYPE_64:
155 flags |= IORESOURCE_MEM_64;
156 break;
157 default:
158 /* mem unknown type treated as 32-bit BAR */
159 break;
160 }
161 return flags;
162}
163
164#define PCI_COMMAND_DECODE_ENABLE (PCI_COMMAND_MEMORY | PCI_COMMAND_IO)
165
166/**
167 * pci_read_base - read a PCI BAR
168 * @dev: the PCI device
169 * @type: type of the BAR
170 * @res: resource buffer to be filled in
171 * @pos: BAR position in the config space
172 *
173 * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
174 */
175int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
176 struct resource *res, unsigned int pos)
177{
178 u32 l, sz, mask;
179 u64 l64, sz64, mask64;
180 u16 orig_cmd;
181 struct pci_bus_region region, inverted_region;
182
183 mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
184
185 /* No printks while decoding is disabled! */
186 if (!dev->mmio_always_on) {
187 pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
188 if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) {
189 pci_write_config_word(dev, PCI_COMMAND,
190 orig_cmd & ~PCI_COMMAND_DECODE_ENABLE);
191 }
192 }
193
194 res->name = pci_name(dev);
195
196 pci_read_config_dword(dev, pos, &l);
197 pci_write_config_dword(dev, pos, l | mask);
198 pci_read_config_dword(dev, pos, &sz);
199 pci_write_config_dword(dev, pos, l);
200
201 /*
202 * All bits set in sz means the device isn't working properly.
203 * If the BAR isn't implemented, all bits must be 0. If it's a
204 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
205 * 1 must be clear.
206 */
207 if (sz == 0xffffffff)
208 sz = 0;
209
210 /*
211 * I don't know how l can have all bits set. Copied from old code.
212 * Maybe it fixes a bug on some ancient platform.
213 */
214 if (l == 0xffffffff)
215 l = 0;
216
217 if (type == pci_bar_unknown) {
218 res->flags = decode_bar(dev, l);
219 res->flags |= IORESOURCE_SIZEALIGN;
220 if (res->flags & IORESOURCE_IO) {
221 l64 = l & PCI_BASE_ADDRESS_IO_MASK;
222 sz64 = sz & PCI_BASE_ADDRESS_IO_MASK;
223 mask64 = PCI_BASE_ADDRESS_IO_MASK & (u32)IO_SPACE_LIMIT;
224 } else {
225 l64 = l & PCI_BASE_ADDRESS_MEM_MASK;
226 sz64 = sz & PCI_BASE_ADDRESS_MEM_MASK;
227 mask64 = (u32)PCI_BASE_ADDRESS_MEM_MASK;
228 }
229 } else {
230 if (l & PCI_ROM_ADDRESS_ENABLE)
231 res->flags |= IORESOURCE_ROM_ENABLE;
232 l64 = l & PCI_ROM_ADDRESS_MASK;
233 sz64 = sz & PCI_ROM_ADDRESS_MASK;
234 mask64 = (u32)PCI_ROM_ADDRESS_MASK;
235 }
236
237 if (res->flags & IORESOURCE_MEM_64) {
238 pci_read_config_dword(dev, pos + 4, &l);
239 pci_write_config_dword(dev, pos + 4, ~0);
240 pci_read_config_dword(dev, pos + 4, &sz);
241 pci_write_config_dword(dev, pos + 4, l);
242
243 l64 |= ((u64)l << 32);
244 sz64 |= ((u64)sz << 32);
245 mask64 |= ((u64)~0 << 32);
246 }
247
248 if (!dev->mmio_always_on && (orig_cmd & PCI_COMMAND_DECODE_ENABLE))
249 pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
250
251 if (!sz64)
252 goto fail;
253
254 sz64 = pci_size(l64, sz64, mask64);
255 if (!sz64) {
256 dev_info(&dev->dev, FW_BUG "reg 0x%x: invalid BAR (can't size)\n",
257 pos);
258 goto fail;
259 }
260
261 if (res->flags & IORESOURCE_MEM_64) {
262 if ((sizeof(pci_bus_addr_t) < 8 || sizeof(resource_size_t) < 8)
263 && sz64 > 0x100000000ULL) {
264 res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
265 res->start = 0;
266 res->end = 0;
267 dev_err(&dev->dev, "reg 0x%x: can't handle BAR larger than 4GB (size %#010llx)\n",
268 pos, (unsigned long long)sz64);
269 goto out;
270 }
271
272 if ((sizeof(pci_bus_addr_t) < 8) && l) {
273 /* Above 32-bit boundary; try to reallocate */
274 res->flags |= IORESOURCE_UNSET;
275 res->start = 0;
276 res->end = sz64;
277 dev_info(&dev->dev, "reg 0x%x: can't handle BAR above 4GB (bus address %#010llx)\n",
278 pos, (unsigned long long)l64);
279 goto out;
280 }
281 }
282
283 region.start = l64;
284 region.end = l64 + sz64;
285
286 pcibios_bus_to_resource(dev->bus, res, ®ion);
287 pcibios_resource_to_bus(dev->bus, &inverted_region, res);
288
289 /*
290 * If "A" is a BAR value (a bus address), "bus_to_resource(A)" is
291 * the corresponding resource address (the physical address used by
292 * the CPU. Converting that resource address back to a bus address
293 * should yield the original BAR value:
294 *
295 * resource_to_bus(bus_to_resource(A)) == A
296 *
297 * If it doesn't, CPU accesses to "bus_to_resource(A)" will not
298 * be claimed by the device.
299 */
300 if (inverted_region.start != region.start) {
301 res->flags |= IORESOURCE_UNSET;
302 res->start = 0;
303 res->end = region.end - region.start;
304 dev_info(&dev->dev, "reg 0x%x: initial BAR value %#010llx invalid\n",
305 pos, (unsigned long long)region.start);
306 }
307
308 goto out;
309
310
311fail:
312 res->flags = 0;
313out:
314 if (res->flags)
315 dev_printk(KERN_DEBUG, &dev->dev, "reg 0x%x: %pR\n", pos, res);
316
317 return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
318}
319
320static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
321{
322 unsigned int pos, reg;
323
324 if (dev->non_compliant_bars)
325 return;
326
327 for (pos = 0; pos < howmany; pos++) {
328 struct resource *res = &dev->resource[pos];
329 reg = PCI_BASE_ADDRESS_0 + (pos << 2);
330 pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
331 }
332
333 if (rom) {
334 struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
335 dev->rom_base_reg = rom;
336 res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
337 IORESOURCE_READONLY | IORESOURCE_SIZEALIGN;
338 __pci_read_base(dev, pci_bar_mem32, res, rom);
339 }
340}
341
342static void pci_read_bridge_io(struct pci_bus *child)
343{
344 struct pci_dev *dev = child->self;
345 u8 io_base_lo, io_limit_lo;
346 unsigned long io_mask, io_granularity, base, limit;
347 struct pci_bus_region region;
348 struct resource *res;
349
350 io_mask = PCI_IO_RANGE_MASK;
351 io_granularity = 0x1000;
352 if (dev->io_window_1k) {
353 /* Support 1K I/O space granularity */
354 io_mask = PCI_IO_1K_RANGE_MASK;
355 io_granularity = 0x400;
356 }
357
358 res = child->resource[0];
359 pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
360 pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
361 base = (io_base_lo & io_mask) << 8;
362 limit = (io_limit_lo & io_mask) << 8;
363
364 if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
365 u16 io_base_hi, io_limit_hi;
366
367 pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
368 pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
369 base |= ((unsigned long) io_base_hi << 16);
370 limit |= ((unsigned long) io_limit_hi << 16);
371 }
372
373 if (base <= limit) {
374 res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
375 region.start = base;
376 region.end = limit + io_granularity - 1;
377 pcibios_bus_to_resource(dev->bus, res, ®ion);
378 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
379 }
380}
381
382static void pci_read_bridge_mmio(struct pci_bus *child)
383{
384 struct pci_dev *dev = child->self;
385 u16 mem_base_lo, mem_limit_lo;
386 unsigned long base, limit;
387 struct pci_bus_region region;
388 struct resource *res;
389
390 res = child->resource[1];
391 pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
392 pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
393 base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
394 limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
395 if (base <= limit) {
396 res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
397 region.start = base;
398 region.end = limit + 0xfffff;
399 pcibios_bus_to_resource(dev->bus, res, ®ion);
400 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
401 }
402}
403
404static void pci_read_bridge_mmio_pref(struct pci_bus *child)
405{
406 struct pci_dev *dev = child->self;
407 u16 mem_base_lo, mem_limit_lo;
408 u64 base64, limit64;
409 pci_bus_addr_t base, limit;
410 struct pci_bus_region region;
411 struct resource *res;
412
413 res = child->resource[2];
414 pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
415 pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
416 base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
417 limit64 = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
418
419 if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
420 u32 mem_base_hi, mem_limit_hi;
421
422 pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
423 pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
424
425 /*
426 * Some bridges set the base > limit by default, and some
427 * (broken) BIOSes do not initialize them. If we find
428 * this, just assume they are not being used.
429 */
430 if (mem_base_hi <= mem_limit_hi) {
431 base64 |= (u64) mem_base_hi << 32;
432 limit64 |= (u64) mem_limit_hi << 32;
433 }
434 }
435
436 base = (pci_bus_addr_t) base64;
437 limit = (pci_bus_addr_t) limit64;
438
439 if (base != base64) {
440 dev_err(&dev->dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
441 (unsigned long long) base64);
442 return;
443 }
444
445 if (base <= limit) {
446 res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
447 IORESOURCE_MEM | IORESOURCE_PREFETCH;
448 if (res->flags & PCI_PREF_RANGE_TYPE_64)
449 res->flags |= IORESOURCE_MEM_64;
450 region.start = base;
451 region.end = limit + 0xfffff;
452 pcibios_bus_to_resource(dev->bus, res, ®ion);
453 dev_printk(KERN_DEBUG, &dev->dev, " bridge window %pR\n", res);
454 }
455}
456
457void pci_read_bridge_bases(struct pci_bus *child)
458{
459 struct pci_dev *dev = child->self;
460 struct resource *res;
461 int i;
462
463 if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
464 return;
465
466 dev_info(&dev->dev, "PCI bridge to %pR%s\n",
467 &child->busn_res,
468 dev->transparent ? " (subtractive decode)" : "");
469
470 pci_bus_remove_resources(child);
471 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
472 child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
473
474 pci_read_bridge_io(child);
475 pci_read_bridge_mmio(child);
476 pci_read_bridge_mmio_pref(child);
477
478 if (dev->transparent) {
479 pci_bus_for_each_resource(child->parent, res, i) {
480 if (res && res->flags) {
481 pci_bus_add_resource(child, res,
482 PCI_SUBTRACTIVE_DECODE);
483 dev_printk(KERN_DEBUG, &dev->dev,
484 " bridge window %pR (subtractive decode)\n",
485 res);
486 }
487 }
488 }
489}
490
491static struct pci_bus *pci_alloc_bus(struct pci_bus *parent)
492{
493 struct pci_bus *b;
494
495 b = kzalloc(sizeof(*b), GFP_KERNEL);
496 if (!b)
497 return NULL;
498
499 INIT_LIST_HEAD(&b->node);
500 INIT_LIST_HEAD(&b->children);
501 INIT_LIST_HEAD(&b->devices);
502 INIT_LIST_HEAD(&b->slots);
503 INIT_LIST_HEAD(&b->resources);
504 b->max_bus_speed = PCI_SPEED_UNKNOWN;
505 b->cur_bus_speed = PCI_SPEED_UNKNOWN;
506#ifdef CONFIG_PCI_DOMAINS_GENERIC
507 if (parent)
508 b->domain_nr = parent->domain_nr;
509#endif
510 return b;
511}
512
513static void pci_release_host_bridge_dev(struct device *dev)
514{
515 struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
516
517 if (bridge->release_fn)
518 bridge->release_fn(bridge);
519
520 pci_free_resource_list(&bridge->windows);
521
522 kfree(bridge);
523}
524
525struct pci_host_bridge *pci_alloc_host_bridge(size_t priv)
526{
527 struct pci_host_bridge *bridge;
528
529 bridge = kzalloc(sizeof(*bridge) + priv, GFP_KERNEL);
530 if (!bridge)
531 return NULL;
532
533 INIT_LIST_HEAD(&bridge->windows);
534
535 return bridge;
536}
537EXPORT_SYMBOL(pci_alloc_host_bridge);
538
539static const unsigned char pcix_bus_speed[] = {
540 PCI_SPEED_UNKNOWN, /* 0 */
541 PCI_SPEED_66MHz_PCIX, /* 1 */
542 PCI_SPEED_100MHz_PCIX, /* 2 */
543 PCI_SPEED_133MHz_PCIX, /* 3 */
544 PCI_SPEED_UNKNOWN, /* 4 */
545 PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
546 PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
547 PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
548 PCI_SPEED_UNKNOWN, /* 8 */
549 PCI_SPEED_66MHz_PCIX_266, /* 9 */
550 PCI_SPEED_100MHz_PCIX_266, /* A */
551 PCI_SPEED_133MHz_PCIX_266, /* B */
552 PCI_SPEED_UNKNOWN, /* C */
553 PCI_SPEED_66MHz_PCIX_533, /* D */
554 PCI_SPEED_100MHz_PCIX_533, /* E */
555 PCI_SPEED_133MHz_PCIX_533 /* F */
556};
557
558const unsigned char pcie_link_speed[] = {
559 PCI_SPEED_UNKNOWN, /* 0 */
560 PCIE_SPEED_2_5GT, /* 1 */
561 PCIE_SPEED_5_0GT, /* 2 */
562 PCIE_SPEED_8_0GT, /* 3 */
563 PCI_SPEED_UNKNOWN, /* 4 */
564 PCI_SPEED_UNKNOWN, /* 5 */
565 PCI_SPEED_UNKNOWN, /* 6 */
566 PCI_SPEED_UNKNOWN, /* 7 */
567 PCI_SPEED_UNKNOWN, /* 8 */
568 PCI_SPEED_UNKNOWN, /* 9 */
569 PCI_SPEED_UNKNOWN, /* A */
570 PCI_SPEED_UNKNOWN, /* B */
571 PCI_SPEED_UNKNOWN, /* C */
572 PCI_SPEED_UNKNOWN, /* D */
573 PCI_SPEED_UNKNOWN, /* E */
574 PCI_SPEED_UNKNOWN /* F */
575};
576
577void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
578{
579 bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS];
580}
581EXPORT_SYMBOL_GPL(pcie_update_link_speed);
582
583static unsigned char agp_speeds[] = {
584 AGP_UNKNOWN,
585 AGP_1X,
586 AGP_2X,
587 AGP_4X,
588 AGP_8X
589};
590
591static enum pci_bus_speed agp_speed(int agp3, int agpstat)
592{
593 int index = 0;
594
595 if (agpstat & 4)
596 index = 3;
597 else if (agpstat & 2)
598 index = 2;
599 else if (agpstat & 1)
600 index = 1;
601 else
602 goto out;
603
604 if (agp3) {
605 index += 2;
606 if (index == 5)
607 index = 0;
608 }
609
610 out:
611 return agp_speeds[index];
612}
613
614static void pci_set_bus_speed(struct pci_bus *bus)
615{
616 struct pci_dev *bridge = bus->self;
617 int pos;
618
619 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
620 if (!pos)
621 pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
622 if (pos) {
623 u32 agpstat, agpcmd;
624
625 pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
626 bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
627
628 pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
629 bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
630 }
631
632 pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
633 if (pos) {
634 u16 status;
635 enum pci_bus_speed max;
636
637 pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
638 &status);
639
640 if (status & PCI_X_SSTATUS_533MHZ) {
641 max = PCI_SPEED_133MHz_PCIX_533;
642 } else if (status & PCI_X_SSTATUS_266MHZ) {
643 max = PCI_SPEED_133MHz_PCIX_266;
644 } else if (status & PCI_X_SSTATUS_133MHZ) {
645 if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2)
646 max = PCI_SPEED_133MHz_PCIX_ECC;
647 else
648 max = PCI_SPEED_133MHz_PCIX;
649 } else {
650 max = PCI_SPEED_66MHz_PCIX;
651 }
652
653 bus->max_bus_speed = max;
654 bus->cur_bus_speed = pcix_bus_speed[
655 (status & PCI_X_SSTATUS_FREQ) >> 6];
656
657 return;
658 }
659
660 if (pci_is_pcie(bridge)) {
661 u32 linkcap;
662 u16 linksta;
663
664 pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
665 bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
666
667 pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
668 pcie_update_link_speed(bus, linksta);
669 }
670}
671
672static struct irq_domain *pci_host_bridge_msi_domain(struct pci_bus *bus)
673{
674 struct irq_domain *d;
675
676 /*
677 * Any firmware interface that can resolve the msi_domain
678 * should be called from here.
679 */
680 d = pci_host_bridge_of_msi_domain(bus);
681 if (!d)
682 d = pci_host_bridge_acpi_msi_domain(bus);
683
684#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
685 /*
686 * If no IRQ domain was found via the OF tree, try looking it up
687 * directly through the fwnode_handle.
688 */
689 if (!d) {
690 struct fwnode_handle *fwnode = pci_root_bus_fwnode(bus);
691
692 if (fwnode)
693 d = irq_find_matching_fwnode(fwnode,
694 DOMAIN_BUS_PCI_MSI);
695 }
696#endif
697
698 return d;
699}
700
701static void pci_set_bus_msi_domain(struct pci_bus *bus)
702{
703 struct irq_domain *d;
704 struct pci_bus *b;
705
706 /*
707 * The bus can be a root bus, a subordinate bus, or a virtual bus
708 * created by an SR-IOV device. Walk up to the first bridge device
709 * found or derive the domain from the host bridge.
710 */
711 for (b = bus, d = NULL; !d && !pci_is_root_bus(b); b = b->parent) {
712 if (b->self)
713 d = dev_get_msi_domain(&b->self->dev);
714 }
715
716 if (!d)
717 d = pci_host_bridge_msi_domain(b);
718
719 dev_set_msi_domain(&bus->dev, d);
720}
721
722int pci_register_host_bridge(struct pci_host_bridge *bridge)
723{
724 struct device *parent = bridge->dev.parent;
725 struct resource_entry *window, *n;
726 struct pci_bus *bus, *b;
727 resource_size_t offset;
728 LIST_HEAD(resources);
729 struct resource *res;
730 char addr[64], *fmt;
731 const char *name;
732 int err;
733
734 bus = pci_alloc_bus(NULL);
735 if (!bus)
736 return -ENOMEM;
737
738 bridge->bus = bus;
739
740 /* temporarily move resources off the list */
741 list_splice_init(&bridge->windows, &resources);
742 bus->sysdata = bridge->sysdata;
743 bus->msi = bridge->msi;
744 bus->ops = bridge->ops;
745 bus->number = bus->busn_res.start = bridge->busnr;
746#ifdef CONFIG_PCI_DOMAINS_GENERIC
747 bus->domain_nr = pci_bus_find_domain_nr(bus, parent);
748#endif
749
750 b = pci_find_bus(pci_domain_nr(bus), bridge->busnr);
751 if (b) {
752 /* If we already got to this bus through a different bridge, ignore it */
753 dev_dbg(&b->dev, "bus already known\n");
754 err = -EEXIST;
755 goto free;
756 }
757
758 dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(bus),
759 bridge->busnr);
760
761 err = pcibios_root_bridge_prepare(bridge);
762 if (err)
763 goto free;
764
765 err = device_register(&bridge->dev);
766 if (err)
767 put_device(&bridge->dev);
768
769 bus->bridge = get_device(&bridge->dev);
770 device_enable_async_suspend(bus->bridge);
771 pci_set_bus_of_node(bus);
772 pci_set_bus_msi_domain(bus);
773
774 if (!parent)
775 set_dev_node(bus->bridge, pcibus_to_node(bus));
776
777 bus->dev.class = &pcibus_class;
778 bus->dev.parent = bus->bridge;
779
780 dev_set_name(&bus->dev, "%04x:%02x", pci_domain_nr(bus), bus->number);
781 name = dev_name(&bus->dev);
782
783 err = device_register(&bus->dev);
784 if (err)
785 goto unregister;
786
787 pcibios_add_bus(bus);
788
789 /* Create legacy_io and legacy_mem files for this bus */
790 pci_create_legacy_files(bus);
791
792 if (parent)
793 dev_info(parent, "PCI host bridge to bus %s\n", name);
794 else
795 pr_info("PCI host bridge to bus %s\n", name);
796
797 /* Add initial resources to the bus */
798 resource_list_for_each_entry_safe(window, n, &resources) {
799 list_move_tail(&window->node, &bridge->windows);
800 offset = window->offset;
801 res = window->res;
802
803 if (res->flags & IORESOURCE_BUS)
804 pci_bus_insert_busn_res(bus, bus->number, res->end);
805 else
806 pci_bus_add_resource(bus, res, 0);
807
808 if (offset) {
809 if (resource_type(res) == IORESOURCE_IO)
810 fmt = " (bus address [%#06llx-%#06llx])";
811 else
812 fmt = " (bus address [%#010llx-%#010llx])";
813
814 snprintf(addr, sizeof(addr), fmt,
815 (unsigned long long)(res->start - offset),
816 (unsigned long long)(res->end - offset));
817 } else
818 addr[0] = '\0';
819
820 dev_info(&bus->dev, "root bus resource %pR%s\n", res, addr);
821 }
822
823 down_write(&pci_bus_sem);
824 list_add_tail(&bus->node, &pci_root_buses);
825 up_write(&pci_bus_sem);
826
827 return 0;
828
829unregister:
830 put_device(&bridge->dev);
831 device_unregister(&bridge->dev);
832
833free:
834 kfree(bus);
835 return err;
836}
837EXPORT_SYMBOL(pci_register_host_bridge);
838
839static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
840 struct pci_dev *bridge, int busnr)
841{
842 struct pci_bus *child;
843 int i;
844 int ret;
845
846 /*
847 * Allocate a new bus, and inherit stuff from the parent..
848 */
849 child = pci_alloc_bus(parent);
850 if (!child)
851 return NULL;
852
853 child->parent = parent;
854 child->ops = parent->ops;
855 child->msi = parent->msi;
856 child->sysdata = parent->sysdata;
857 child->bus_flags = parent->bus_flags;
858
859 /* initialize some portions of the bus device, but don't register it
860 * now as the parent is not properly set up yet.
861 */
862 child->dev.class = &pcibus_class;
863 dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
864
865 /*
866 * Set up the primary, secondary and subordinate
867 * bus numbers.
868 */
869 child->number = child->busn_res.start = busnr;
870 child->primary = parent->busn_res.start;
871 child->busn_res.end = 0xff;
872
873 if (!bridge) {
874 child->dev.parent = parent->bridge;
875 goto add_dev;
876 }
877
878 child->self = bridge;
879 child->bridge = get_device(&bridge->dev);
880 child->dev.parent = child->bridge;
881 pci_set_bus_of_node(child);
882 pci_set_bus_speed(child);
883
884 /* Set up default resource pointers and names.. */
885 for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
886 child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
887 child->resource[i]->name = child->name;
888 }
889 bridge->subordinate = child;
890
891add_dev:
892 pci_set_bus_msi_domain(child);
893 ret = device_register(&child->dev);
894 WARN_ON(ret < 0);
895
896 pcibios_add_bus(child);
897
898 if (child->ops->add_bus) {
899 ret = child->ops->add_bus(child);
900 if (WARN_ON(ret < 0))
901 dev_err(&child->dev, "failed to add bus: %d\n", ret);
902 }
903
904 /* Create legacy_io and legacy_mem files for this bus */
905 pci_create_legacy_files(child);
906
907 return child;
908}
909
910struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev,
911 int busnr)
912{
913 struct pci_bus *child;
914
915 child = pci_alloc_child_bus(parent, dev, busnr);
916 if (child) {
917 down_write(&pci_bus_sem);
918 list_add_tail(&child->node, &parent->children);
919 up_write(&pci_bus_sem);
920 }
921 return child;
922}
923EXPORT_SYMBOL(pci_add_new_bus);
924
925static void pci_enable_crs(struct pci_dev *pdev)
926{
927 u16 root_cap = 0;
928
929 /* Enable CRS Software Visibility if supported */
930 pcie_capability_read_word(pdev, PCI_EXP_RTCAP, &root_cap);
931 if (root_cap & PCI_EXP_RTCAP_CRSVIS)
932 pcie_capability_set_word(pdev, PCI_EXP_RTCTL,
933 PCI_EXP_RTCTL_CRSSVE);
934}
935
936/*
937 * If it's a bridge, configure it and scan the bus behind it.
938 * For CardBus bridges, we don't scan behind as the devices will
939 * be handled by the bridge driver itself.
940 *
941 * We need to process bridges in two passes -- first we scan those
942 * already configured by the BIOS and after we are done with all of
943 * them, we proceed to assigning numbers to the remaining buses in
944 * order to avoid overlaps between old and new bus numbers.
945 */
946int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
947{
948 struct pci_bus *child;
949 int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
950 u32 buses, i, j = 0;
951 u16 bctl;
952 u8 primary, secondary, subordinate;
953 int broken = 0;
954
955 /*
956 * Make sure the bridge is powered on to be able to access config
957 * space of devices below it.
958 */
959 pm_runtime_get_sync(&dev->dev);
960
961 pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
962 primary = buses & 0xFF;
963 secondary = (buses >> 8) & 0xFF;
964 subordinate = (buses >> 16) & 0xFF;
965
966 dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
967 secondary, subordinate, pass);
968
969 if (!primary && (primary != bus->number) && secondary && subordinate) {
970 dev_warn(&dev->dev, "Primary bus is hard wired to 0\n");
971 primary = bus->number;
972 }
973
974 /* Check if setup is sensible at all */
975 if (!pass &&
976 (primary != bus->number || secondary <= bus->number ||
977 secondary > subordinate)) {
978 dev_info(&dev->dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
979 secondary, subordinate);
980 broken = 1;
981 }
982
983 /* Disable MasterAbortMode during probing to avoid reporting
984 of bus errors (in some architectures) */
985 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
986 pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
987 bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
988
989 pci_enable_crs(dev);
990
991 if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
992 !is_cardbus && !broken) {
993 unsigned int cmax;
994 /*
995 * Bus already configured by firmware, process it in the first
996 * pass and just note the configuration.
997 */
998 if (pass)
999 goto out;
1000
1001 /*
1002 * The bus might already exist for two reasons: Either we are
1003 * rescanning the bus or the bus is reachable through more than
1004 * one bridge. The second case can happen with the i450NX
1005 * chipset.
1006 */
1007 child = pci_find_bus(pci_domain_nr(bus), secondary);
1008 if (!child) {
1009 child = pci_add_new_bus(bus, dev, secondary);
1010 if (!child)
1011 goto out;
1012 child->primary = primary;
1013 pci_bus_insert_busn_res(child, secondary, subordinate);
1014 child->bridge_ctl = bctl;
1015 }
1016
1017 cmax = pci_scan_child_bus(child);
1018 if (cmax > subordinate)
1019 dev_warn(&dev->dev, "bridge has subordinate %02x but max busn %02x\n",
1020 subordinate, cmax);
1021 /* subordinate should equal child->busn_res.end */
1022 if (subordinate > max)
1023 max = subordinate;
1024 } else {
1025 /*
1026 * We need to assign a number to this bus which we always
1027 * do in the second pass.
1028 */
1029 if (!pass) {
1030 if (pcibios_assign_all_busses() || broken || is_cardbus)
1031 /* Temporarily disable forwarding of the
1032 configuration cycles on all bridges in
1033 this bus segment to avoid possible
1034 conflicts in the second pass between two
1035 bridges programmed with overlapping
1036 bus ranges. */
1037 pci_write_config_dword(dev, PCI_PRIMARY_BUS,
1038 buses & ~0xffffff);
1039 goto out;
1040 }
1041
1042 /* Clear errors */
1043 pci_write_config_word(dev, PCI_STATUS, 0xffff);
1044
1045 /* Prevent assigning a bus number that already exists.
1046 * This can happen when a bridge is hot-plugged, so in
1047 * this case we only re-scan this bus. */
1048 child = pci_find_bus(pci_domain_nr(bus), max+1);
1049 if (!child) {
1050 child = pci_add_new_bus(bus, dev, max+1);
1051 if (!child)
1052 goto out;
1053 pci_bus_insert_busn_res(child, max+1, 0xff);
1054 }
1055 max++;
1056 buses = (buses & 0xff000000)
1057 | ((unsigned int)(child->primary) << 0)
1058 | ((unsigned int)(child->busn_res.start) << 8)
1059 | ((unsigned int)(child->busn_res.end) << 16);
1060
1061 /*
1062 * yenta.c forces a secondary latency timer of 176.
1063 * Copy that behaviour here.
1064 */
1065 if (is_cardbus) {
1066 buses &= ~0xff000000;
1067 buses |= CARDBUS_LATENCY_TIMER << 24;
1068 }
1069
1070 /*
1071 * We need to blast all three values with a single write.
1072 */
1073 pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
1074
1075 if (!is_cardbus) {
1076 child->bridge_ctl = bctl;
1077 max = pci_scan_child_bus(child);
1078 } else {
1079 /*
1080 * For CardBus bridges, we leave 4 bus numbers
1081 * as cards with a PCI-to-PCI bridge can be
1082 * inserted later.
1083 */
1084 for (i = 0; i < CARDBUS_RESERVE_BUSNR; i++) {
1085 struct pci_bus *parent = bus;
1086 if (pci_find_bus(pci_domain_nr(bus),
1087 max+i+1))
1088 break;
1089 while (parent->parent) {
1090 if ((!pcibios_assign_all_busses()) &&
1091 (parent->busn_res.end > max) &&
1092 (parent->busn_res.end <= max+i)) {
1093 j = 1;
1094 }
1095 parent = parent->parent;
1096 }
1097 if (j) {
1098 /*
1099 * Often, there are two cardbus bridges
1100 * -- try to leave one valid bus number
1101 * for each one.
1102 */
1103 i /= 2;
1104 break;
1105 }
1106 }
1107 max += i;
1108 }
1109 /*
1110 * Set the subordinate bus number to its real value.
1111 */
1112 pci_bus_update_busn_res_end(child, max);
1113 pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
1114 }
1115
1116 sprintf(child->name,
1117 (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
1118 pci_domain_nr(bus), child->number);
1119
1120 /* Has only triggered on CardBus, fixup is in yenta_socket */
1121 while (bus->parent) {
1122 if ((child->busn_res.end > bus->busn_res.end) ||
1123 (child->number > bus->busn_res.end) ||
1124 (child->number < bus->number) ||
1125 (child->busn_res.end < bus->number)) {
1126 dev_info(&child->dev, "%pR %s hidden behind%s bridge %s %pR\n",
1127 &child->busn_res,
1128 (bus->number > child->busn_res.end &&
1129 bus->busn_res.end < child->number) ?
1130 "wholly" : "partially",
1131 bus->self->transparent ? " transparent" : "",
1132 dev_name(&bus->dev),
1133 &bus->busn_res);
1134 }
1135 bus = bus->parent;
1136 }
1137
1138out:
1139 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
1140
1141 pm_runtime_put(&dev->dev);
1142
1143 return max;
1144}
1145EXPORT_SYMBOL(pci_scan_bridge);
1146
1147/*
1148 * Read interrupt line and base address registers.
1149 * The architecture-dependent code can tweak these, of course.
1150 */
1151static void pci_read_irq(struct pci_dev *dev)
1152{
1153 unsigned char irq;
1154
1155 pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
1156 dev->pin = irq;
1157 if (irq)
1158 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
1159 dev->irq = irq;
1160}
1161
1162void set_pcie_port_type(struct pci_dev *pdev)
1163{
1164 int pos;
1165 u16 reg16;
1166 int type;
1167 struct pci_dev *parent;
1168
1169 pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
1170 if (!pos)
1171 return;
1172
1173 pdev->pcie_cap = pos;
1174 pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
1175 pdev->pcie_flags_reg = reg16;
1176 pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16);
1177 pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
1178
1179 /*
1180 * A Root Port or a PCI-to-PCIe bridge is always the upstream end
1181 * of a Link. No PCIe component has two Links. Two Links are
1182 * connected by a Switch that has a Port on each Link and internal
1183 * logic to connect the two Ports.
1184 */
1185 type = pci_pcie_type(pdev);
1186 if (type == PCI_EXP_TYPE_ROOT_PORT ||
1187 type == PCI_EXP_TYPE_PCIE_BRIDGE)
1188 pdev->has_secondary_link = 1;
1189 else if (type == PCI_EXP_TYPE_UPSTREAM ||
1190 type == PCI_EXP_TYPE_DOWNSTREAM) {
1191 parent = pci_upstream_bridge(pdev);
1192
1193 /*
1194 * Usually there's an upstream device (Root Port or Switch
1195 * Downstream Port), but we can't assume one exists.
1196 */
1197 if (parent && !parent->has_secondary_link)
1198 pdev->has_secondary_link = 1;
1199 }
1200}
1201
1202void set_pcie_hotplug_bridge(struct pci_dev *pdev)
1203{
1204 u32 reg32;
1205
1206 pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32);
1207 if (reg32 & PCI_EXP_SLTCAP_HPC)
1208 pdev->is_hotplug_bridge = 1;
1209}
1210
1211/**
1212 * pci_ext_cfg_is_aliased - is ext config space just an alias of std config?
1213 * @dev: PCI device
1214 *
1215 * PCI Express to PCI/PCI-X Bridge Specification, rev 1.0, 4.1.4 says that
1216 * when forwarding a type1 configuration request the bridge must check that
1217 * the extended register address field is zero. The bridge is not permitted
1218 * to forward the transactions and must handle it as an Unsupported Request.
1219 * Some bridges do not follow this rule and simply drop the extended register
1220 * bits, resulting in the standard config space being aliased, every 256
1221 * bytes across the entire configuration space. Test for this condition by
1222 * comparing the first dword of each potential alias to the vendor/device ID.
1223 * Known offenders:
1224 * ASM1083/1085 PCIe-to-PCI Reversible Bridge (1b21:1080, rev 01 & 03)
1225 * AMD/ATI SBx00 PCI to PCI Bridge (1002:4384, rev 40)
1226 */
1227static bool pci_ext_cfg_is_aliased(struct pci_dev *dev)
1228{
1229#ifdef CONFIG_PCI_QUIRKS
1230 int pos;
1231 u32 header, tmp;
1232
1233 pci_read_config_dword(dev, PCI_VENDOR_ID, &header);
1234
1235 for (pos = PCI_CFG_SPACE_SIZE;
1236 pos < PCI_CFG_SPACE_EXP_SIZE; pos += PCI_CFG_SPACE_SIZE) {
1237 if (pci_read_config_dword(dev, pos, &tmp) != PCIBIOS_SUCCESSFUL
1238 || header != tmp)
1239 return false;
1240 }
1241
1242 return true;
1243#else
1244 return false;
1245#endif
1246}
1247
1248/**
1249 * pci_cfg_space_size - get the configuration space size of the PCI device.
1250 * @dev: PCI device
1251 *
1252 * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1253 * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1254 * access it. Maybe we don't have a way to generate extended config space
1255 * accesses, or the device is behind a reverse Express bridge. So we try
1256 * reading the dword at 0x100 which must either be 0 or a valid extended
1257 * capability header.
1258 */
1259static int pci_cfg_space_size_ext(struct pci_dev *dev)
1260{
1261 u32 status;
1262 int pos = PCI_CFG_SPACE_SIZE;
1263
1264 if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1265 return PCI_CFG_SPACE_SIZE;
1266 if (status == 0xffffffff || pci_ext_cfg_is_aliased(dev))
1267 return PCI_CFG_SPACE_SIZE;
1268
1269 return PCI_CFG_SPACE_EXP_SIZE;
1270}
1271
1272int pci_cfg_space_size(struct pci_dev *dev)
1273{
1274 int pos;
1275 u32 status;
1276 u16 class;
1277
1278 class = dev->class >> 8;
1279 if (class == PCI_CLASS_BRIDGE_HOST)
1280 return pci_cfg_space_size_ext(dev);
1281
1282 if (pci_is_pcie(dev))
1283 return pci_cfg_space_size_ext(dev);
1284
1285 pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1286 if (!pos)
1287 return PCI_CFG_SPACE_SIZE;
1288
1289 pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1290 if (status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ))
1291 return pci_cfg_space_size_ext(dev);
1292
1293 return PCI_CFG_SPACE_SIZE;
1294}
1295
1296#define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
1297
1298static void pci_msi_setup_pci_dev(struct pci_dev *dev)
1299{
1300 /*
1301 * Disable the MSI hardware to avoid screaming interrupts
1302 * during boot. This is the power on reset default so
1303 * usually this should be a noop.
1304 */
1305 dev->msi_cap = pci_find_capability(dev, PCI_CAP_ID_MSI);
1306 if (dev->msi_cap)
1307 pci_msi_set_enable(dev, 0);
1308
1309 dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX);
1310 if (dev->msix_cap)
1311 pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
1312}
1313
1314/**
1315 * pci_setup_device - fill in class and map information of a device
1316 * @dev: the device structure to fill
1317 *
1318 * Initialize the device structure with information about the device's
1319 * vendor,class,memory and IO-space addresses,IRQ lines etc.
1320 * Called at initialisation of the PCI subsystem and by CardBus services.
1321 * Returns 0 on success and negative if unknown type of device (not normal,
1322 * bridge or CardBus).
1323 */
1324int pci_setup_device(struct pci_dev *dev)
1325{
1326 u32 class;
1327 u16 cmd;
1328 u8 hdr_type;
1329 int pos = 0;
1330 struct pci_bus_region region;
1331 struct resource *res;
1332
1333 if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
1334 return -EIO;
1335
1336 dev->sysdata = dev->bus->sysdata;
1337 dev->dev.parent = dev->bus->bridge;
1338 dev->dev.bus = &pci_bus_type;
1339 dev->hdr_type = hdr_type & 0x7f;
1340 dev->multifunction = !!(hdr_type & 0x80);
1341 dev->error_state = pci_channel_io_normal;
1342 set_pcie_port_type(dev);
1343
1344 pci_dev_assign_slot(dev);
1345 /* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
1346 set this higher, assuming the system even supports it. */
1347 dev->dma_mask = 0xffffffff;
1348
1349 dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
1350 dev->bus->number, PCI_SLOT(dev->devfn),
1351 PCI_FUNC(dev->devfn));
1352
1353 pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
1354 dev->revision = class & 0xff;
1355 dev->class = class >> 8; /* upper 3 bytes */
1356
1357 dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %02x class %#08x\n",
1358 dev->vendor, dev->device, dev->hdr_type, dev->class);
1359
1360 /* need to have dev->class ready */
1361 dev->cfg_size = pci_cfg_space_size(dev);
1362
1363 /* "Unknown power state" */
1364 dev->current_state = PCI_UNKNOWN;
1365
1366 /* Early fixups, before probing the BARs */
1367 pci_fixup_device(pci_fixup_early, dev);
1368 /* device class may be changed after fixup */
1369 class = dev->class >> 8;
1370
1371 if (dev->non_compliant_bars) {
1372 pci_read_config_word(dev, PCI_COMMAND, &cmd);
1373 if (cmd & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) {
1374 dev_info(&dev->dev, "device has non-compliant BARs; disabling IO/MEM decoding\n");
1375 cmd &= ~PCI_COMMAND_IO;
1376 cmd &= ~PCI_COMMAND_MEMORY;
1377 pci_write_config_word(dev, PCI_COMMAND, cmd);
1378 }
1379 }
1380
1381 switch (dev->hdr_type) { /* header type */
1382 case PCI_HEADER_TYPE_NORMAL: /* standard header */
1383 if (class == PCI_CLASS_BRIDGE_PCI)
1384 goto bad;
1385 pci_read_irq(dev);
1386 pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1387 pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1388 pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
1389
1390 /*
1391 * Do the ugly legacy mode stuff here rather than broken chip
1392 * quirk code. Legacy mode ATA controllers have fixed
1393 * addresses. These are not always echoed in BAR0-3, and
1394 * BAR0-3 in a few cases contain junk!
1395 */
1396 if (class == PCI_CLASS_STORAGE_IDE) {
1397 u8 progif;
1398 pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1399 if ((progif & 1) == 0) {
1400 region.start = 0x1F0;
1401 region.end = 0x1F7;
1402 res = &dev->resource[0];
1403 res->flags = LEGACY_IO_RESOURCE;
1404 pcibios_bus_to_resource(dev->bus, res, ®ion);
1405 dev_info(&dev->dev, "legacy IDE quirk: reg 0x10: %pR\n",
1406 res);
1407 region.start = 0x3F6;
1408 region.end = 0x3F6;
1409 res = &dev->resource[1];
1410 res->flags = LEGACY_IO_RESOURCE;
1411 pcibios_bus_to_resource(dev->bus, res, ®ion);
1412 dev_info(&dev->dev, "legacy IDE quirk: reg 0x14: %pR\n",
1413 res);
1414 }
1415 if ((progif & 4) == 0) {
1416 region.start = 0x170;
1417 region.end = 0x177;
1418 res = &dev->resource[2];
1419 res->flags = LEGACY_IO_RESOURCE;
1420 pcibios_bus_to_resource(dev->bus, res, ®ion);
1421 dev_info(&dev->dev, "legacy IDE quirk: reg 0x18: %pR\n",
1422 res);
1423 region.start = 0x376;
1424 region.end = 0x376;
1425 res = &dev->resource[3];
1426 res->flags = LEGACY_IO_RESOURCE;
1427 pcibios_bus_to_resource(dev->bus, res, ®ion);
1428 dev_info(&dev->dev, "legacy IDE quirk: reg 0x1c: %pR\n",
1429 res);
1430 }
1431 }
1432 break;
1433
1434 case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1435 if (class != PCI_CLASS_BRIDGE_PCI)
1436 goto bad;
1437 /* The PCI-to-PCI bridge spec requires that subtractive
1438 decoding (i.e. transparent) bridge must have programming
1439 interface code of 0x01. */
1440 pci_read_irq(dev);
1441 dev->transparent = ((dev->class & 0xff) == 1);
1442 pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1443 set_pcie_hotplug_bridge(dev);
1444 pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1445 if (pos) {
1446 pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1447 pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1448 }
1449 break;
1450
1451 case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1452 if (class != PCI_CLASS_BRIDGE_CARDBUS)
1453 goto bad;
1454 pci_read_irq(dev);
1455 pci_read_bases(dev, 1, 0);
1456 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1457 pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1458 break;
1459
1460 default: /* unknown header */
1461 dev_err(&dev->dev, "unknown header type %02x, ignoring device\n",
1462 dev->hdr_type);
1463 return -EIO;
1464
1465 bad:
1466 dev_err(&dev->dev, "ignoring class %#08x (doesn't match header type %02x)\n",
1467 dev->class, dev->hdr_type);
1468 dev->class = PCI_CLASS_NOT_DEFINED << 8;
1469 }
1470
1471 /* We found a fine healthy device, go go go... */
1472 return 0;
1473}
1474
1475static void pci_configure_mps(struct pci_dev *dev)
1476{
1477 struct pci_dev *bridge = pci_upstream_bridge(dev);
1478 int mps, p_mps, rc;
1479
1480 if (!pci_is_pcie(dev) || !bridge || !pci_is_pcie(bridge))
1481 return;
1482
1483 mps = pcie_get_mps(dev);
1484 p_mps = pcie_get_mps(bridge);
1485
1486 if (mps == p_mps)
1487 return;
1488
1489 if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
1490 dev_warn(&dev->dev, "Max Payload Size %d, but upstream %s set to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
1491 mps, pci_name(bridge), p_mps);
1492 return;
1493 }
1494
1495 /*
1496 * Fancier MPS configuration is done later by
1497 * pcie_bus_configure_settings()
1498 */
1499 if (pcie_bus_config != PCIE_BUS_DEFAULT)
1500 return;
1501
1502 rc = pcie_set_mps(dev, p_mps);
1503 if (rc) {
1504 dev_warn(&dev->dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
1505 p_mps);
1506 return;
1507 }
1508
1509 dev_info(&dev->dev, "Max Payload Size set to %d (was %d, max %d)\n",
1510 p_mps, mps, 128 << dev->pcie_mpss);
1511}
1512
1513static struct hpp_type0 pci_default_type0 = {
1514 .revision = 1,
1515 .cache_line_size = 8,
1516 .latency_timer = 0x40,
1517 .enable_serr = 0,
1518 .enable_perr = 0,
1519};
1520
1521static void program_hpp_type0(struct pci_dev *dev, struct hpp_type0 *hpp)
1522{
1523 u16 pci_cmd, pci_bctl;
1524
1525 if (!hpp)
1526 hpp = &pci_default_type0;
1527
1528 if (hpp->revision > 1) {
1529 dev_warn(&dev->dev,
1530 "PCI settings rev %d not supported; using defaults\n",
1531 hpp->revision);
1532 hpp = &pci_default_type0;
1533 }
1534
1535 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, hpp->cache_line_size);
1536 pci_write_config_byte(dev, PCI_LATENCY_TIMER, hpp->latency_timer);
1537 pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
1538 if (hpp->enable_serr)
1539 pci_cmd |= PCI_COMMAND_SERR;
1540 if (hpp->enable_perr)
1541 pci_cmd |= PCI_COMMAND_PARITY;
1542 pci_write_config_word(dev, PCI_COMMAND, pci_cmd);
1543
1544 /* Program bridge control value */
1545 if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
1546 pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER,
1547 hpp->latency_timer);
1548 pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &pci_bctl);
1549 if (hpp->enable_serr)
1550 pci_bctl |= PCI_BRIDGE_CTL_SERR;
1551 if (hpp->enable_perr)
1552 pci_bctl |= PCI_BRIDGE_CTL_PARITY;
1553 pci_write_config_word(dev, PCI_BRIDGE_CONTROL, pci_bctl);
1554 }
1555}
1556
1557static void program_hpp_type1(struct pci_dev *dev, struct hpp_type1 *hpp)
1558{
1559 if (hpp)
1560 dev_warn(&dev->dev, "PCI-X settings not supported\n");
1561}
1562
1563static bool pcie_root_rcb_set(struct pci_dev *dev)
1564{
1565 struct pci_dev *rp = pcie_find_root_port(dev);
1566 u16 lnkctl;
1567
1568 if (!rp)
1569 return false;
1570
1571 pcie_capability_read_word(rp, PCI_EXP_LNKCTL, &lnkctl);
1572 if (lnkctl & PCI_EXP_LNKCTL_RCB)
1573 return true;
1574
1575 return false;
1576}
1577
1578static void program_hpp_type2(struct pci_dev *dev, struct hpp_type2 *hpp)
1579{
1580 int pos;
1581 u32 reg32;
1582
1583 if (!hpp)
1584 return;
1585
1586 if (hpp->revision > 1) {
1587 dev_warn(&dev->dev, "PCIe settings rev %d not supported\n",
1588 hpp->revision);
1589 return;
1590 }
1591
1592 /*
1593 * Don't allow _HPX to change MPS or MRRS settings. We manage
1594 * those to make sure they're consistent with the rest of the
1595 * platform.
1596 */
1597 hpp->pci_exp_devctl_and |= PCI_EXP_DEVCTL_PAYLOAD |
1598 PCI_EXP_DEVCTL_READRQ;
1599 hpp->pci_exp_devctl_or &= ~(PCI_EXP_DEVCTL_PAYLOAD |
1600 PCI_EXP_DEVCTL_READRQ);
1601
1602 /* Initialize Device Control Register */
1603 pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
1604 ~hpp->pci_exp_devctl_and, hpp->pci_exp_devctl_or);
1605
1606 /* Initialize Link Control Register */
1607 if (pcie_cap_has_lnkctl(dev)) {
1608
1609 /*
1610 * If the Root Port supports Read Completion Boundary of
1611 * 128, set RCB to 128. Otherwise, clear it.
1612 */
1613 hpp->pci_exp_lnkctl_and |= PCI_EXP_LNKCTL_RCB;
1614 hpp->pci_exp_lnkctl_or &= ~PCI_EXP_LNKCTL_RCB;
1615 if (pcie_root_rcb_set(dev))
1616 hpp->pci_exp_lnkctl_or |= PCI_EXP_LNKCTL_RCB;
1617
1618 pcie_capability_clear_and_set_word(dev, PCI_EXP_LNKCTL,
1619 ~hpp->pci_exp_lnkctl_and, hpp->pci_exp_lnkctl_or);
1620 }
1621
1622 /* Find Advanced Error Reporting Enhanced Capability */
1623 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
1624 if (!pos)
1625 return;
1626
1627 /* Initialize Uncorrectable Error Mask Register */
1628 pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, ®32);
1629 reg32 = (reg32 & hpp->unc_err_mask_and) | hpp->unc_err_mask_or;
1630 pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, reg32);
1631
1632 /* Initialize Uncorrectable Error Severity Register */
1633 pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, ®32);
1634 reg32 = (reg32 & hpp->unc_err_sever_and) | hpp->unc_err_sever_or;
1635 pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, reg32);
1636
1637 /* Initialize Correctable Error Mask Register */
1638 pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK, ®32);
1639 reg32 = (reg32 & hpp->cor_err_mask_and) | hpp->cor_err_mask_or;
1640 pci_write_config_dword(dev, pos + PCI_ERR_COR_MASK, reg32);
1641
1642 /* Initialize Advanced Error Capabilities and Control Register */
1643 pci_read_config_dword(dev, pos + PCI_ERR_CAP, ®32);
1644 reg32 = (reg32 & hpp->adv_err_cap_and) | hpp->adv_err_cap_or;
1645 pci_write_config_dword(dev, pos + PCI_ERR_CAP, reg32);
1646
1647 /*
1648 * FIXME: The following two registers are not supported yet.
1649 *
1650 * o Secondary Uncorrectable Error Severity Register
1651 * o Secondary Uncorrectable Error Mask Register
1652 */
1653}
1654
1655static void pci_configure_device(struct pci_dev *dev)
1656{
1657 struct hotplug_params hpp;
1658 int ret;
1659
1660 pci_configure_mps(dev);
1661
1662 memset(&hpp, 0, sizeof(hpp));
1663 ret = pci_get_hp_params(dev, &hpp);
1664 if (ret)
1665 return;
1666
1667 program_hpp_type2(dev, hpp.t2);
1668 program_hpp_type1(dev, hpp.t1);
1669 program_hpp_type0(dev, hpp.t0);
1670}
1671
1672static void pci_release_capabilities(struct pci_dev *dev)
1673{
1674 pci_vpd_release(dev);
1675 pci_iov_release(dev);
1676 pci_free_cap_save_buffers(dev);
1677}
1678
1679/**
1680 * pci_release_dev - free a pci device structure when all users of it are finished.
1681 * @dev: device that's been disconnected
1682 *
1683 * Will be called only by the device core when all users of this pci device are
1684 * done.
1685 */
1686static void pci_release_dev(struct device *dev)
1687{
1688 struct pci_dev *pci_dev;
1689
1690 pci_dev = to_pci_dev(dev);
1691 pci_release_capabilities(pci_dev);
1692 pci_release_of_node(pci_dev);
1693 pcibios_release_device(pci_dev);
1694 pci_bus_put(pci_dev->bus);
1695 kfree(pci_dev->driver_override);
1696 kfree(pci_dev->dma_alias_mask);
1697 kfree(pci_dev);
1698}
1699
1700struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
1701{
1702 struct pci_dev *dev;
1703
1704 dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
1705 if (!dev)
1706 return NULL;
1707
1708 INIT_LIST_HEAD(&dev->bus_list);
1709 dev->dev.type = &pci_dev_type;
1710 dev->bus = pci_bus_get(bus);
1711
1712 return dev;
1713}
1714EXPORT_SYMBOL(pci_alloc_dev);
1715
1716bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
1717 int crs_timeout)
1718{
1719 int delay = 1;
1720
1721 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1722 return false;
1723
1724 /* some broken boards return 0 or ~0 if a slot is empty: */
1725 if (*l == 0xffffffff || *l == 0x00000000 ||
1726 *l == 0x0000ffff || *l == 0xffff0000)
1727 return false;
1728
1729 /*
1730 * Configuration Request Retry Status. Some root ports return the
1731 * actual device ID instead of the synthetic ID (0xFFFF) required
1732 * by the PCIe spec. Ignore the device ID and only check for
1733 * (vendor id == 1).
1734 */
1735 while ((*l & 0xffff) == 0x0001) {
1736 if (!crs_timeout)
1737 return false;
1738
1739 msleep(delay);
1740 delay *= 2;
1741 if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1742 return false;
1743 /* Card hasn't responded in 60 seconds? Must be stuck. */
1744 if (delay > crs_timeout) {
1745 printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not responding\n",
1746 pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
1747 PCI_FUNC(devfn));
1748 return false;
1749 }
1750 }
1751
1752 return true;
1753}
1754EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
1755
1756/*
1757 * Read the config data for a PCI device, sanity-check it
1758 * and fill in the dev structure...
1759 */
1760static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
1761{
1762 struct pci_dev *dev;
1763 u32 l;
1764
1765 if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
1766 return NULL;
1767
1768 dev = pci_alloc_dev(bus);
1769 if (!dev)
1770 return NULL;
1771
1772 dev->devfn = devfn;
1773 dev->vendor = l & 0xffff;
1774 dev->device = (l >> 16) & 0xffff;
1775
1776 pci_set_of_node(dev);
1777
1778 if (pci_setup_device(dev)) {
1779 pci_bus_put(dev->bus);
1780 kfree(dev);
1781 return NULL;
1782 }
1783
1784 return dev;
1785}
1786
1787static void pci_init_capabilities(struct pci_dev *dev)
1788{
1789 /* Enhanced Allocation */
1790 pci_ea_init(dev);
1791
1792 /* Setup MSI caps & disable MSI/MSI-X interrupts */
1793 pci_msi_setup_pci_dev(dev);
1794
1795 /* Buffers for saving PCIe and PCI-X capabilities */
1796 pci_allocate_cap_save_buffers(dev);
1797
1798 /* Power Management */
1799 pci_pm_init(dev);
1800
1801 /* Vital Product Data */
1802 pci_vpd_init(dev);
1803
1804 /* Alternative Routing-ID Forwarding */
1805 pci_configure_ari(dev);
1806
1807 /* Single Root I/O Virtualization */
1808 pci_iov_init(dev);
1809
1810 /* Address Translation Services */
1811 pci_ats_init(dev);
1812
1813 /* Enable ACS P2P upstream forwarding */
1814 pci_enable_acs(dev);
1815
1816 /* Precision Time Measurement */
1817 pci_ptm_init(dev);
1818
1819 /* Advanced Error Reporting */
1820 pci_aer_init(dev);
1821}
1822
1823/*
1824 * This is the equivalent of pci_host_bridge_msi_domain that acts on
1825 * devices. Firmware interfaces that can select the MSI domain on a
1826 * per-device basis should be called from here.
1827 */
1828static struct irq_domain *pci_dev_msi_domain(struct pci_dev *dev)
1829{
1830 struct irq_domain *d;
1831
1832 /*
1833 * If a domain has been set through the pcibios_add_device
1834 * callback, then this is the one (platform code knows best).
1835 */
1836 d = dev_get_msi_domain(&dev->dev);
1837 if (d)
1838 return d;
1839
1840 /*
1841 * Let's see if we have a firmware interface able to provide
1842 * the domain.
1843 */
1844 d = pci_msi_get_device_domain(dev);
1845 if (d)
1846 return d;
1847
1848 return NULL;
1849}
1850
1851static void pci_set_msi_domain(struct pci_dev *dev)
1852{
1853 struct irq_domain *d;
1854
1855 /*
1856 * If the platform or firmware interfaces cannot supply a
1857 * device-specific MSI domain, then inherit the default domain
1858 * from the host bridge itself.
1859 */
1860 d = pci_dev_msi_domain(dev);
1861 if (!d)
1862 d = dev_get_msi_domain(&dev->bus->dev);
1863
1864 dev_set_msi_domain(&dev->dev, d);
1865}
1866
1867/**
1868 * pci_dma_configure - Setup DMA configuration
1869 * @dev: ptr to pci_dev struct of the PCI device
1870 *
1871 * Function to update PCI devices's DMA configuration using the same
1872 * info from the OF node or ACPI node of host bridge's parent (if any).
1873 */
1874static void pci_dma_configure(struct pci_dev *dev)
1875{
1876 struct device *bridge = pci_get_host_bridge_device(dev);
1877
1878 if (IS_ENABLED(CONFIG_OF) &&
1879 bridge->parent && bridge->parent->of_node) {
1880 of_dma_configure(&dev->dev, bridge->parent->of_node);
1881 } else if (has_acpi_companion(bridge)) {
1882 struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);
1883 enum dev_dma_attr attr = acpi_get_dma_attr(adev);
1884
1885 if (attr == DEV_DMA_NOT_SUPPORTED)
1886 dev_warn(&dev->dev, "DMA not supported.\n");
1887 else
1888 acpi_dma_configure(&dev->dev, attr);
1889 }
1890
1891 pci_put_host_bridge_device(bridge);
1892}
1893
1894void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
1895{
1896 int ret;
1897
1898 pci_configure_device(dev);
1899
1900 device_initialize(&dev->dev);
1901 dev->dev.release = pci_release_dev;
1902
1903 set_dev_node(&dev->dev, pcibus_to_node(bus));
1904 dev->dev.dma_mask = &dev->dma_mask;
1905 dev->dev.dma_parms = &dev->dma_parms;
1906 dev->dev.coherent_dma_mask = 0xffffffffull;
1907 pci_dma_configure(dev);
1908
1909 pci_set_dma_max_seg_size(dev, 65536);
1910 pci_set_dma_seg_boundary(dev, 0xffffffff);
1911
1912 /* Fix up broken headers */
1913 pci_fixup_device(pci_fixup_header, dev);
1914
1915 /* moved out from quirk header fixup code */
1916 pci_reassigndev_resource_alignment(dev);
1917
1918 /* Clear the state_saved flag. */
1919 dev->state_saved = false;
1920
1921 /* Initialize various capabilities */
1922 pci_init_capabilities(dev);
1923
1924 /*
1925 * Add the device to our list of discovered devices
1926 * and the bus list for fixup functions, etc.
1927 */
1928 down_write(&pci_bus_sem);
1929 list_add_tail(&dev->bus_list, &bus->devices);
1930 up_write(&pci_bus_sem);
1931
1932 ret = pcibios_add_device(dev);
1933 WARN_ON(ret < 0);
1934
1935 /* Setup MSI irq domain */
1936 pci_set_msi_domain(dev);
1937
1938 /* Notifier could use PCI capabilities */
1939 dev->match_driver = false;
1940 ret = device_add(&dev->dev);
1941 WARN_ON(ret < 0);
1942}
1943
1944struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn)
1945{
1946 struct pci_dev *dev;
1947
1948 dev = pci_get_slot(bus, devfn);
1949 if (dev) {
1950 pci_dev_put(dev);
1951 return dev;
1952 }
1953
1954 dev = pci_scan_device(bus, devfn);
1955 if (!dev)
1956 return NULL;
1957
1958 pci_device_add(dev, bus);
1959
1960 return dev;
1961}
1962EXPORT_SYMBOL(pci_scan_single_device);
1963
1964static unsigned next_fn(struct pci_bus *bus, struct pci_dev *dev, unsigned fn)
1965{
1966 int pos;
1967 u16 cap = 0;
1968 unsigned next_fn;
1969
1970 if (pci_ari_enabled(bus)) {
1971 if (!dev)
1972 return 0;
1973 pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1974 if (!pos)
1975 return 0;
1976
1977 pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap);
1978 next_fn = PCI_ARI_CAP_NFN(cap);
1979 if (next_fn <= fn)
1980 return 0; /* protect against malformed list */
1981
1982 return next_fn;
1983 }
1984
1985 /* dev may be NULL for non-contiguous multifunction devices */
1986 if (!dev || dev->multifunction)
1987 return (fn + 1) % 8;
1988
1989 return 0;
1990}
1991
1992static int only_one_child(struct pci_bus *bus)
1993{
1994 struct pci_dev *parent = bus->self;
1995
1996 if (!parent || !pci_is_pcie(parent))
1997 return 0;
1998 if (pci_pcie_type(parent) == PCI_EXP_TYPE_ROOT_PORT)
1999 return 1;
2000
2001 /*
2002 * PCIe downstream ports are bridges that normally lead to only a
2003 * device 0, but if PCI_SCAN_ALL_PCIE_DEVS is set, scan all
2004 * possible devices, not just device 0. See PCIe spec r3.0,
2005 * sec 7.3.1.
2006 */
2007 if (parent->has_secondary_link &&
2008 !pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
2009 return 1;
2010 return 0;
2011}
2012
2013/**
2014 * pci_scan_slot - scan a PCI slot on a bus for devices.
2015 * @bus: PCI bus to scan
2016 * @devfn: slot number to scan (must have zero function.)
2017 *
2018 * Scan a PCI slot on the specified PCI bus for devices, adding
2019 * discovered devices to the @bus->devices list. New devices
2020 * will not have is_added set.
2021 *
2022 * Returns the number of new devices found.
2023 */
2024int pci_scan_slot(struct pci_bus *bus, int devfn)
2025{
2026 unsigned fn, nr = 0;
2027 struct pci_dev *dev;
2028
2029 if (only_one_child(bus) && (devfn > 0))
2030 return 0; /* Already scanned the entire slot */
2031
2032 dev = pci_scan_single_device(bus, devfn);
2033 if (!dev)
2034 return 0;
2035 if (!dev->is_added)
2036 nr++;
2037
2038 for (fn = next_fn(bus, dev, 0); fn > 0; fn = next_fn(bus, dev, fn)) {
2039 dev = pci_scan_single_device(bus, devfn + fn);
2040 if (dev) {
2041 if (!dev->is_added)
2042 nr++;
2043 dev->multifunction = 1;
2044 }
2045 }
2046
2047 /* only one slot has pcie device */
2048 if (bus->self && nr)
2049 pcie_aspm_init_link_state(bus->self);
2050
2051 return nr;
2052}
2053EXPORT_SYMBOL(pci_scan_slot);
2054
2055static int pcie_find_smpss(struct pci_dev *dev, void *data)
2056{
2057 u8 *smpss = data;
2058
2059 if (!pci_is_pcie(dev))
2060 return 0;
2061
2062 /*
2063 * We don't have a way to change MPS settings on devices that have
2064 * drivers attached. A hot-added device might support only the minimum
2065 * MPS setting (MPS=128). Therefore, if the fabric contains a bridge
2066 * where devices may be hot-added, we limit the fabric MPS to 128 so
2067 * hot-added devices will work correctly.
2068 *
2069 * However, if we hot-add a device to a slot directly below a Root
2070 * Port, it's impossible for there to be other existing devices below
2071 * the port. We don't limit the MPS in this case because we can
2072 * reconfigure MPS on both the Root Port and the hot-added device,
2073 * and there are no other devices involved.
2074 *
2075 * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
2076 */
2077 if (dev->is_hotplug_bridge &&
2078 pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
2079 *smpss = 0;
2080
2081 if (*smpss > dev->pcie_mpss)
2082 *smpss = dev->pcie_mpss;
2083
2084 return 0;
2085}
2086
2087static void pcie_write_mps(struct pci_dev *dev, int mps)
2088{
2089 int rc;
2090
2091 if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
2092 mps = 128 << dev->pcie_mpss;
2093
2094 if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
2095 dev->bus->self)
2096 /* For "Performance", the assumption is made that
2097 * downstream communication will never be larger than
2098 * the MRRS. So, the MPS only needs to be configured
2099 * for the upstream communication. This being the case,
2100 * walk from the top down and set the MPS of the child
2101 * to that of the parent bus.
2102 *
2103 * Configure the device MPS with the smaller of the
2104 * device MPSS or the bridge MPS (which is assumed to be
2105 * properly configured at this point to the largest
2106 * allowable MPS based on its parent bus).
2107 */
2108 mps = min(mps, pcie_get_mps(dev->bus->self));
2109 }
2110
2111 rc = pcie_set_mps(dev, mps);
2112 if (rc)
2113 dev_err(&dev->dev, "Failed attempting to set the MPS\n");
2114}
2115
2116static void pcie_write_mrrs(struct pci_dev *dev)
2117{
2118 int rc, mrrs;
2119
2120 /* In the "safe" case, do not configure the MRRS. There appear to be
2121 * issues with setting MRRS to 0 on a number of devices.
2122 */
2123 if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
2124 return;
2125
2126 /* For Max performance, the MRRS must be set to the largest supported
2127 * value. However, it cannot be configured larger than the MPS the
2128 * device or the bus can support. This should already be properly
2129 * configured by a prior call to pcie_write_mps.
2130 */
2131 mrrs = pcie_get_mps(dev);
2132
2133 /* MRRS is a R/W register. Invalid values can be written, but a
2134 * subsequent read will verify if the value is acceptable or not.
2135 * If the MRRS value provided is not acceptable (e.g., too large),
2136 * shrink the value until it is acceptable to the HW.
2137 */
2138 while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
2139 rc = pcie_set_readrq(dev, mrrs);
2140 if (!rc)
2141 break;
2142
2143 dev_warn(&dev->dev, "Failed attempting to set the MRRS\n");
2144 mrrs /= 2;
2145 }
2146
2147 if (mrrs < 128)
2148 dev_err(&dev->dev, "MRRS was unable to be configured with a safe value. If problems are experienced, try running with pci=pcie_bus_safe\n");
2149}
2150
2151static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
2152{
2153 int mps, orig_mps;
2154
2155 if (!pci_is_pcie(dev))
2156 return 0;
2157
2158 if (pcie_bus_config == PCIE_BUS_TUNE_OFF ||
2159 pcie_bus_config == PCIE_BUS_DEFAULT)
2160 return 0;
2161
2162 mps = 128 << *(u8 *)data;
2163 orig_mps = pcie_get_mps(dev);
2164
2165 pcie_write_mps(dev, mps);
2166 pcie_write_mrrs(dev);
2167
2168 dev_info(&dev->dev, "Max Payload Size set to %4d/%4d (was %4d), Max Read Rq %4d\n",
2169 pcie_get_mps(dev), 128 << dev->pcie_mpss,
2170 orig_mps, pcie_get_readrq(dev));
2171
2172 return 0;
2173}
2174
2175/* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down,
2176 * parents then children fashion. If this changes, then this code will not
2177 * work as designed.
2178 */
2179void pcie_bus_configure_settings(struct pci_bus *bus)
2180{
2181 u8 smpss = 0;
2182
2183 if (!bus->self)
2184 return;
2185
2186 if (!pci_is_pcie(bus->self))
2187 return;
2188
2189 /* FIXME - Peer to peer DMA is possible, though the endpoint would need
2190 * to be aware of the MPS of the destination. To work around this,
2191 * simply force the MPS of the entire system to the smallest possible.
2192 */
2193 if (pcie_bus_config == PCIE_BUS_PEER2PEER)
2194 smpss = 0;
2195
2196 if (pcie_bus_config == PCIE_BUS_SAFE) {
2197 smpss = bus->self->pcie_mpss;
2198
2199 pcie_find_smpss(bus->self, &smpss);
2200 pci_walk_bus(bus, pcie_find_smpss, &smpss);
2201 }
2202
2203 pcie_bus_configure_set(bus->self, &smpss);
2204 pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
2205}
2206EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
2207
2208unsigned int pci_scan_child_bus(struct pci_bus *bus)
2209{
2210 unsigned int devfn, pass, max = bus->busn_res.start;
2211 struct pci_dev *dev;
2212
2213 dev_dbg(&bus->dev, "scanning bus\n");
2214
2215 /* Go find them, Rover! */
2216 for (devfn = 0; devfn < 0x100; devfn += 8)
2217 pci_scan_slot(bus, devfn);
2218
2219 /* Reserve buses for SR-IOV capability. */
2220 max += pci_iov_bus_range(bus);
2221
2222 /*
2223 * After performing arch-dependent fixup of the bus, look behind
2224 * all PCI-to-PCI bridges on this bus.
2225 */
2226 if (!bus->is_added) {
2227 dev_dbg(&bus->dev, "fixups for bus\n");
2228 pcibios_fixup_bus(bus);
2229 bus->is_added = 1;
2230 }
2231
2232 for (pass = 0; pass < 2; pass++)
2233 list_for_each_entry(dev, &bus->devices, bus_list) {
2234 if (pci_is_bridge(dev))
2235 max = pci_scan_bridge(bus, dev, max, pass);
2236 }
2237
2238 /*
2239 * Make sure a hotplug bridge has at least the minimum requested
2240 * number of buses.
2241 */
2242 if (bus->self && bus->self->is_hotplug_bridge && pci_hotplug_bus_size) {
2243 if (max - bus->busn_res.start < pci_hotplug_bus_size - 1)
2244 max = bus->busn_res.start + pci_hotplug_bus_size - 1;
2245 }
2246
2247 /*
2248 * We've scanned the bus and so we know all about what's on
2249 * the other side of any bridges that may be on this bus plus
2250 * any devices.
2251 *
2252 * Return how far we've got finding sub-buses.
2253 */
2254 dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
2255 return max;
2256}
2257EXPORT_SYMBOL_GPL(pci_scan_child_bus);
2258
2259/**
2260 * pcibios_root_bridge_prepare - Platform-specific host bridge setup.
2261 * @bridge: Host bridge to set up.
2262 *
2263 * Default empty implementation. Replace with an architecture-specific setup
2264 * routine, if necessary.
2265 */
2266int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
2267{
2268 return 0;
2269}
2270
2271void __weak pcibios_add_bus(struct pci_bus *bus)
2272{
2273}
2274
2275void __weak pcibios_remove_bus(struct pci_bus *bus)
2276{
2277}
2278
2279static struct pci_bus *pci_create_root_bus_msi(struct device *parent,
2280 int bus, struct pci_ops *ops, void *sysdata,
2281 struct list_head *resources, struct msi_controller *msi)
2282{
2283 int error;
2284 struct pci_host_bridge *bridge;
2285
2286 bridge = pci_alloc_host_bridge(0);
2287 if (!bridge)
2288 return NULL;
2289
2290 bridge->dev.parent = parent;
2291 bridge->dev.release = pci_release_host_bridge_dev;
2292
2293 list_splice_init(resources, &bridge->windows);
2294 bridge->sysdata = sysdata;
2295 bridge->busnr = bus;
2296 bridge->ops = ops;
2297 bridge->msi = msi;
2298
2299 error = pci_register_host_bridge(bridge);
2300 if (error < 0)
2301 goto err_out;
2302
2303 return bridge->bus;
2304
2305err_out:
2306 kfree(bridge);
2307 return NULL;
2308}
2309
2310struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
2311 struct pci_ops *ops, void *sysdata, struct list_head *resources)
2312{
2313 return pci_create_root_bus_msi(parent, bus, ops, sysdata, resources,
2314 NULL);
2315}
2316EXPORT_SYMBOL_GPL(pci_create_root_bus);
2317
2318int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
2319{
2320 struct resource *res = &b->busn_res;
2321 struct resource *parent_res, *conflict;
2322
2323 res->start = bus;
2324 res->end = bus_max;
2325 res->flags = IORESOURCE_BUS;
2326
2327 if (!pci_is_root_bus(b))
2328 parent_res = &b->parent->busn_res;
2329 else {
2330 parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
2331 res->flags |= IORESOURCE_PCI_FIXED;
2332 }
2333
2334 conflict = request_resource_conflict(parent_res, res);
2335
2336 if (conflict)
2337 dev_printk(KERN_DEBUG, &b->dev,
2338 "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
2339 res, pci_is_root_bus(b) ? "domain " : "",
2340 parent_res, conflict->name, conflict);
2341
2342 return conflict == NULL;
2343}
2344
2345int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
2346{
2347 struct resource *res = &b->busn_res;
2348 struct resource old_res = *res;
2349 resource_size_t size;
2350 int ret;
2351
2352 if (res->start > bus_max)
2353 return -EINVAL;
2354
2355 size = bus_max - res->start + 1;
2356 ret = adjust_resource(res, res->start, size);
2357 dev_printk(KERN_DEBUG, &b->dev,
2358 "busn_res: %pR end %s updated to %02x\n",
2359 &old_res, ret ? "can not be" : "is", bus_max);
2360
2361 if (!ret && !res->parent)
2362 pci_bus_insert_busn_res(b, res->start, res->end);
2363
2364 return ret;
2365}
2366
2367void pci_bus_release_busn_res(struct pci_bus *b)
2368{
2369 struct resource *res = &b->busn_res;
2370 int ret;
2371
2372 if (!res->flags || !res->parent)
2373 return;
2374
2375 ret = release_resource(res);
2376 dev_printk(KERN_DEBUG, &b->dev,
2377 "busn_res: %pR %s released\n",
2378 res, ret ? "can not be" : "is");
2379}
2380
2381struct pci_bus *pci_scan_root_bus_msi(struct device *parent, int bus,
2382 struct pci_ops *ops, void *sysdata,
2383 struct list_head *resources, struct msi_controller *msi)
2384{
2385 struct resource_entry *window;
2386 bool found = false;
2387 struct pci_bus *b;
2388 int max;
2389
2390 resource_list_for_each_entry(window, resources)
2391 if (window->res->flags & IORESOURCE_BUS) {
2392 found = true;
2393 break;
2394 }
2395
2396 b = pci_create_root_bus_msi(parent, bus, ops, sysdata, resources, msi);
2397 if (!b)
2398 return NULL;
2399
2400 if (!found) {
2401 dev_info(&b->dev,
2402 "No busn resource found for root bus, will use [bus %02x-ff]\n",
2403 bus);
2404 pci_bus_insert_busn_res(b, bus, 255);
2405 }
2406
2407 max = pci_scan_child_bus(b);
2408
2409 if (!found)
2410 pci_bus_update_busn_res_end(b, max);
2411
2412 return b;
2413}
2414
2415struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
2416 struct pci_ops *ops, void *sysdata, struct list_head *resources)
2417{
2418 return pci_scan_root_bus_msi(parent, bus, ops, sysdata, resources,
2419 NULL);
2420}
2421EXPORT_SYMBOL(pci_scan_root_bus);
2422
2423struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
2424 void *sysdata)
2425{
2426 LIST_HEAD(resources);
2427 struct pci_bus *b;
2428
2429 pci_add_resource(&resources, &ioport_resource);
2430 pci_add_resource(&resources, &iomem_resource);
2431 pci_add_resource(&resources, &busn_resource);
2432 b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
2433 if (b) {
2434 pci_scan_child_bus(b);
2435 } else {
2436 pci_free_resource_list(&resources);
2437 }
2438 return b;
2439}
2440EXPORT_SYMBOL(pci_scan_bus);
2441
2442/**
2443 * pci_rescan_bus_bridge_resize - scan a PCI bus for devices.
2444 * @bridge: PCI bridge for the bus to scan
2445 *
2446 * Scan a PCI bus and child buses for new devices, add them,
2447 * and enable them, resizing bridge mmio/io resource if necessary
2448 * and possible. The caller must ensure the child devices are already
2449 * removed for resizing to occur.
2450 *
2451 * Returns the max number of subordinate bus discovered.
2452 */
2453unsigned int pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
2454{
2455 unsigned int max;
2456 struct pci_bus *bus = bridge->subordinate;
2457
2458 max = pci_scan_child_bus(bus);
2459
2460 pci_assign_unassigned_bridge_resources(bridge);
2461
2462 pci_bus_add_devices(bus);
2463
2464 return max;
2465}
2466
2467/**
2468 * pci_rescan_bus - scan a PCI bus for devices.
2469 * @bus: PCI bus to scan
2470 *
2471 * Scan a PCI bus and child buses for new devices, adds them,
2472 * and enables them.
2473 *
2474 * Returns the max number of subordinate bus discovered.
2475 */
2476unsigned int pci_rescan_bus(struct pci_bus *bus)
2477{
2478 unsigned int max;
2479
2480 max = pci_scan_child_bus(bus);
2481 pci_assign_unassigned_bus_resources(bus);
2482 pci_bus_add_devices(bus);
2483
2484 return max;
2485}
2486EXPORT_SYMBOL_GPL(pci_rescan_bus);
2487
2488/*
2489 * pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal
2490 * routines should always be executed under this mutex.
2491 */
2492static DEFINE_MUTEX(pci_rescan_remove_lock);
2493
2494void pci_lock_rescan_remove(void)
2495{
2496 mutex_lock(&pci_rescan_remove_lock);
2497}
2498EXPORT_SYMBOL_GPL(pci_lock_rescan_remove);
2499
2500void pci_unlock_rescan_remove(void)
2501{
2502 mutex_unlock(&pci_rescan_remove_lock);
2503}
2504EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove);
2505
2506static int __init pci_sort_bf_cmp(const struct device *d_a,
2507 const struct device *d_b)
2508{
2509 const struct pci_dev *a = to_pci_dev(d_a);
2510 const struct pci_dev *b = to_pci_dev(d_b);
2511
2512 if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
2513 else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
2514
2515 if (a->bus->number < b->bus->number) return -1;
2516 else if (a->bus->number > b->bus->number) return 1;
2517
2518 if (a->devfn < b->devfn) return -1;
2519 else if (a->devfn > b->devfn) return 1;
2520
2521 return 0;
2522}
2523
2524void __init pci_sort_breadthfirst(void)
2525{
2526 bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);
2527}