Line data Source code
1 : // SPDX-License-Identifier: GPL-2.0
2 : /*
3 : * PCI detection and setup code
4 : */
5 :
6 : #include <linux/kernel.h>
7 : #include <linux/delay.h>
8 : #include <linux/init.h>
9 : #include <linux/pci.h>
10 : #include <linux/msi.h>
11 : #include <linux/of_device.h>
12 : #include <linux/of_pci.h>
13 : #include <linux/pci_hotplug.h>
14 : #include <linux/slab.h>
15 : #include <linux/module.h>
16 : #include <linux/cpumask.h>
17 : #include <linux/aer.h>
18 : #include <linux/acpi.h>
19 : #include <linux/hypervisor.h>
20 : #include <linux/irqdomain.h>
21 : #include <linux/pm_runtime.h>
22 : #include <linux/bitfield.h>
23 : #include "pci.h"
24 :
25 : #define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
26 : #define CARDBUS_RESERVE_BUSNR 3
27 :
28 : static struct resource busn_resource = {
29 : .name = "PCI busn",
30 : .start = 0,
31 : .end = 255,
32 : .flags = IORESOURCE_BUS,
33 : };
34 :
35 : /* Ugh. Need to stop exporting this to modules. */
36 : LIST_HEAD(pci_root_buses);
37 : EXPORT_SYMBOL(pci_root_buses);
38 :
39 : static LIST_HEAD(pci_domain_busn_res_list);
40 :
41 : struct pci_domain_busn_res {
42 : struct list_head list;
43 : struct resource res;
44 : int domain_nr;
45 : };
46 :
47 0 : static struct resource *get_pci_domain_busn_res(int domain_nr)
48 : {
49 : struct pci_domain_busn_res *r;
50 :
51 0 : list_for_each_entry(r, &pci_domain_busn_res_list, list)
52 0 : if (r->domain_nr == domain_nr)
53 0 : return &r->res;
54 :
55 0 : r = kzalloc(sizeof(*r), GFP_KERNEL);
56 0 : if (!r)
57 : return NULL;
58 :
59 0 : r->domain_nr = domain_nr;
60 0 : r->res.start = 0;
61 0 : r->res.end = 0xff;
62 0 : r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
63 :
64 0 : list_add_tail(&r->list, &pci_domain_busn_res_list);
65 :
66 0 : return &r->res;
67 : }
68 :
69 : /*
70 : * Some device drivers need know if PCI is initiated.
71 : * Basically, we think PCI is not initiated when there
72 : * is no device to be found on the pci_bus_type.
73 : */
74 0 : int no_pci_devices(void)
75 : {
76 : struct device *dev;
77 : int no_devices;
78 :
79 0 : dev = bus_find_next_device(&pci_bus_type, NULL);
80 0 : no_devices = (dev == NULL);
81 0 : put_device(dev);
82 0 : return no_devices;
83 : }
84 : EXPORT_SYMBOL(no_pci_devices);
85 :
86 : /*
87 : * PCI Bus Class
88 : */
89 0 : static void release_pcibus_dev(struct device *dev)
90 : {
91 0 : struct pci_bus *pci_bus = to_pci_bus(dev);
92 :
93 0 : put_device(pci_bus->bridge);
94 0 : pci_bus_remove_resources(pci_bus);
95 0 : pci_release_bus_of_node(pci_bus);
96 0 : kfree(pci_bus);
97 0 : }
98 :
99 : static struct class pcibus_class = {
100 : .name = "pci_bus",
101 : .dev_release = &release_pcibus_dev,
102 : .dev_groups = pcibus_groups,
103 : };
104 :
105 1 : static int __init pcibus_class_init(void)
106 : {
107 1 : return class_register(&pcibus_class);
108 : }
109 : postcore_initcall(pcibus_class_init);
110 :
111 : static u64 pci_size(u64 base, u64 maxbase, u64 mask)
112 : {
113 0 : u64 size = mask & maxbase; /* Find the significant bits */
114 0 : if (!size)
115 : return 0;
116 :
117 : /*
118 : * Get the lowest of them to find the decode size, and from that
119 : * the extent.
120 : */
121 0 : size = size & ~(size-1);
122 :
123 : /*
124 : * base == maxbase can be valid only if the BAR has already been
125 : * programmed with all 1s.
126 : */
127 0 : if (base == maxbase && ((base | (size - 1)) & mask) != mask)
128 : return 0;
129 :
130 : return size;
131 : }
132 :
133 : static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
134 : {
135 : u32 mem_type;
136 : unsigned long flags;
137 :
138 0 : if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
139 0 : flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
140 0 : flags |= IORESOURCE_IO;
141 : return flags;
142 : }
143 :
144 0 : flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
145 0 : flags |= IORESOURCE_MEM;
146 0 : if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
147 0 : flags |= IORESOURCE_PREFETCH;
148 :
149 0 : mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
150 0 : switch (mem_type) {
151 : case PCI_BASE_ADDRESS_MEM_TYPE_32:
152 : break;
153 : case PCI_BASE_ADDRESS_MEM_TYPE_1M:
154 : /* 1M mem BAR treated as 32-bit BAR */
155 : break;
156 : case PCI_BASE_ADDRESS_MEM_TYPE_64:
157 0 : flags |= IORESOURCE_MEM_64;
158 : break;
159 : default:
160 : /* mem unknown type treated as 32-bit BAR */
161 : break;
162 : }
163 : return flags;
164 : }
165 :
166 : #define PCI_COMMAND_DECODE_ENABLE (PCI_COMMAND_MEMORY | PCI_COMMAND_IO)
167 :
168 : /**
169 : * __pci_read_base - Read a PCI BAR
170 : * @dev: the PCI device
171 : * @type: type of the BAR
172 : * @res: resource buffer to be filled in
173 : * @pos: BAR position in the config space
174 : *
175 : * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
176 : */
177 0 : int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
178 : struct resource *res, unsigned int pos)
179 : {
180 0 : u32 l = 0, sz = 0, mask;
181 : u64 l64, sz64, mask64;
182 : u16 orig_cmd;
183 : struct pci_bus_region region, inverted_region;
184 :
185 0 : mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
186 :
187 : /* No printks while decoding is disabled! */
188 0 : if (!dev->mmio_always_on) {
189 0 : pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
190 0 : if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) {
191 0 : pci_write_config_word(dev, PCI_COMMAND,
192 : orig_cmd & ~PCI_COMMAND_DECODE_ENABLE);
193 : }
194 : }
195 :
196 0 : res->name = pci_name(dev);
197 :
198 0 : pci_read_config_dword(dev, pos, &l);
199 0 : pci_write_config_dword(dev, pos, l | mask);
200 0 : pci_read_config_dword(dev, pos, &sz);
201 0 : pci_write_config_dword(dev, pos, l);
202 :
203 : /*
204 : * All bits set in sz means the device isn't working properly.
205 : * If the BAR isn't implemented, all bits must be 0. If it's a
206 : * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
207 : * 1 must be clear.
208 : */
209 0 : if (PCI_POSSIBLE_ERROR(sz))
210 0 : sz = 0;
211 :
212 : /*
213 : * I don't know how l can have all bits set. Copied from old code.
214 : * Maybe it fixes a bug on some ancient platform.
215 : */
216 0 : if (PCI_POSSIBLE_ERROR(l))
217 0 : l = 0;
218 :
219 0 : if (type == pci_bar_unknown) {
220 0 : res->flags = decode_bar(dev, l);
221 0 : res->flags |= IORESOURCE_SIZEALIGN;
222 0 : if (res->flags & IORESOURCE_IO) {
223 0 : l64 = l & PCI_BASE_ADDRESS_IO_MASK;
224 0 : sz64 = sz & PCI_BASE_ADDRESS_IO_MASK;
225 0 : mask64 = PCI_BASE_ADDRESS_IO_MASK & (u32)IO_SPACE_LIMIT;
226 : } else {
227 0 : l64 = l & PCI_BASE_ADDRESS_MEM_MASK;
228 0 : sz64 = sz & PCI_BASE_ADDRESS_MEM_MASK;
229 0 : mask64 = (u32)PCI_BASE_ADDRESS_MEM_MASK;
230 : }
231 : } else {
232 0 : if (l & PCI_ROM_ADDRESS_ENABLE)
233 0 : res->flags |= IORESOURCE_ROM_ENABLE;
234 0 : l64 = l & PCI_ROM_ADDRESS_MASK;
235 0 : sz64 = sz & PCI_ROM_ADDRESS_MASK;
236 0 : mask64 = PCI_ROM_ADDRESS_MASK;
237 : }
238 :
239 0 : if (res->flags & IORESOURCE_MEM_64) {
240 0 : pci_read_config_dword(dev, pos + 4, &l);
241 0 : pci_write_config_dword(dev, pos + 4, ~0);
242 0 : pci_read_config_dword(dev, pos + 4, &sz);
243 0 : pci_write_config_dword(dev, pos + 4, l);
244 :
245 0 : l64 |= ((u64)l << 32);
246 0 : sz64 |= ((u64)sz << 32);
247 0 : mask64 |= ((u64)~0 << 32);
248 : }
249 :
250 0 : if (!dev->mmio_always_on && (orig_cmd & PCI_COMMAND_DECODE_ENABLE))
251 0 : pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
252 :
253 0 : if (!sz64)
254 : goto fail;
255 :
256 0 : sz64 = pci_size(l64, sz64, mask64);
257 0 : if (!sz64) {
258 0 : pci_info(dev, FW_BUG "reg 0x%x: invalid BAR (can't size)\n",
259 : pos);
260 0 : goto fail;
261 : }
262 :
263 : if (res->flags & IORESOURCE_MEM_64) {
264 : if ((sizeof(pci_bus_addr_t) < 8 || sizeof(resource_size_t) < 8)
265 : && sz64 > 0x100000000ULL) {
266 : res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
267 : res->start = 0;
268 : res->end = 0;
269 : pci_err(dev, "reg 0x%x: can't handle BAR larger than 4GB (size %#010llx)\n",
270 : pos, (unsigned long long)sz64);
271 : goto out;
272 : }
273 :
274 : if ((sizeof(pci_bus_addr_t) < 8) && l) {
275 : /* Above 32-bit boundary; try to reallocate */
276 : res->flags |= IORESOURCE_UNSET;
277 : res->start = 0;
278 : res->end = sz64 - 1;
279 : pci_info(dev, "reg 0x%x: can't handle BAR above 4GB (bus address %#010llx)\n",
280 : pos, (unsigned long long)l64);
281 : goto out;
282 : }
283 : }
284 :
285 0 : region.start = l64;
286 0 : region.end = l64 + sz64 - 1;
287 :
288 0 : pcibios_bus_to_resource(dev->bus, res, ®ion);
289 0 : pcibios_resource_to_bus(dev->bus, &inverted_region, res);
290 :
291 : /*
292 : * If "A" is a BAR value (a bus address), "bus_to_resource(A)" is
293 : * the corresponding resource address (the physical address used by
294 : * the CPU. Converting that resource address back to a bus address
295 : * should yield the original BAR value:
296 : *
297 : * resource_to_bus(bus_to_resource(A)) == A
298 : *
299 : * If it doesn't, CPU accesses to "bus_to_resource(A)" will not
300 : * be claimed by the device.
301 : */
302 0 : if (inverted_region.start != region.start) {
303 0 : res->flags |= IORESOURCE_UNSET;
304 0 : res->start = 0;
305 0 : res->end = region.end - region.start;
306 0 : pci_info(dev, "reg 0x%x: initial BAR value %#010llx invalid\n",
307 : pos, (unsigned long long)region.start);
308 : }
309 :
310 : goto out;
311 :
312 :
313 : fail:
314 0 : res->flags = 0;
315 : out:
316 0 : if (res->flags)
317 0 : pci_info(dev, "reg 0x%x: %pR\n", pos, res);
318 :
319 0 : return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
320 : }
321 :
322 0 : static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
323 : {
324 : unsigned int pos, reg;
325 :
326 0 : if (dev->non_compliant_bars)
327 : return;
328 :
329 : /* Per PCIe r4.0, sec 9.3.4.1.11, the VF BARs are all RO Zero */
330 0 : if (dev->is_virtfn)
331 : return;
332 :
333 0 : for (pos = 0; pos < howmany; pos++) {
334 0 : struct resource *res = &dev->resource[pos];
335 0 : reg = PCI_BASE_ADDRESS_0 + (pos << 2);
336 0 : pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
337 : }
338 :
339 0 : if (rom) {
340 0 : struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
341 0 : dev->rom_base_reg = rom;
342 0 : res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
343 : IORESOURCE_READONLY | IORESOURCE_SIZEALIGN;
344 0 : __pci_read_base(dev, pci_bar_mem32, res, rom);
345 : }
346 : }
347 :
348 0 : static void pci_read_bridge_windows(struct pci_dev *bridge)
349 : {
350 : u16 io;
351 : u32 pmem, tmp;
352 :
353 0 : pci_read_config_word(bridge, PCI_IO_BASE, &io);
354 0 : if (!io) {
355 0 : pci_write_config_word(bridge, PCI_IO_BASE, 0xe0f0);
356 0 : pci_read_config_word(bridge, PCI_IO_BASE, &io);
357 0 : pci_write_config_word(bridge, PCI_IO_BASE, 0x0);
358 : }
359 0 : if (io)
360 0 : bridge->io_window = 1;
361 :
362 : /*
363 : * DECchip 21050 pass 2 errata: the bridge may miss an address
364 : * disconnect boundary by one PCI data phase. Workaround: do not
365 : * use prefetching on this device.
366 : */
367 0 : if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001)
368 0 : return;
369 :
370 0 : pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
371 0 : if (!pmem) {
372 0 : pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE,
373 : 0xffe0fff0);
374 0 : pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
375 0 : pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0);
376 : }
377 0 : if (!pmem)
378 : return;
379 :
380 0 : bridge->pref_window = 1;
381 :
382 0 : if ((pmem & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
383 :
384 : /*
385 : * Bridge claims to have a 64-bit prefetchable memory
386 : * window; verify that the upper bits are actually
387 : * writable.
388 : */
389 0 : pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &pmem);
390 0 : pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32,
391 : 0xffffffff);
392 0 : pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &tmp);
393 0 : pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, pmem);
394 0 : if (tmp)
395 0 : bridge->pref_64_window = 1;
396 : }
397 : }
398 :
399 0 : static void pci_read_bridge_io(struct pci_bus *child)
400 : {
401 0 : struct pci_dev *dev = child->self;
402 : u8 io_base_lo, io_limit_lo;
403 : unsigned long io_mask, io_granularity, base, limit;
404 : struct pci_bus_region region;
405 : struct resource *res;
406 :
407 0 : io_mask = PCI_IO_RANGE_MASK;
408 0 : io_granularity = 0x1000;
409 0 : if (dev->io_window_1k) {
410 : /* Support 1K I/O space granularity */
411 0 : io_mask = PCI_IO_1K_RANGE_MASK;
412 0 : io_granularity = 0x400;
413 : }
414 :
415 0 : res = child->resource[0];
416 0 : pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
417 0 : pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
418 0 : base = (io_base_lo & io_mask) << 8;
419 0 : limit = (io_limit_lo & io_mask) << 8;
420 :
421 0 : if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
422 : u16 io_base_hi, io_limit_hi;
423 :
424 0 : pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
425 0 : pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
426 0 : base |= ((unsigned long) io_base_hi << 16);
427 0 : limit |= ((unsigned long) io_limit_hi << 16);
428 : }
429 :
430 0 : if (base <= limit) {
431 0 : res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
432 0 : region.start = base;
433 0 : region.end = limit + io_granularity - 1;
434 0 : pcibios_bus_to_resource(dev->bus, res, ®ion);
435 0 : pci_info(dev, " bridge window %pR\n", res);
436 : }
437 0 : }
438 :
439 0 : static void pci_read_bridge_mmio(struct pci_bus *child)
440 : {
441 0 : struct pci_dev *dev = child->self;
442 : u16 mem_base_lo, mem_limit_lo;
443 : unsigned long base, limit;
444 : struct pci_bus_region region;
445 : struct resource *res;
446 :
447 0 : res = child->resource[1];
448 0 : pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
449 0 : pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
450 0 : base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
451 0 : limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
452 0 : if (base <= limit) {
453 0 : res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
454 0 : region.start = base;
455 0 : region.end = limit + 0xfffff;
456 0 : pcibios_bus_to_resource(dev->bus, res, ®ion);
457 0 : pci_info(dev, " bridge window %pR\n", res);
458 : }
459 0 : }
460 :
461 0 : static void pci_read_bridge_mmio_pref(struct pci_bus *child)
462 : {
463 0 : struct pci_dev *dev = child->self;
464 : u16 mem_base_lo, mem_limit_lo;
465 : u64 base64, limit64;
466 : pci_bus_addr_t base, limit;
467 : struct pci_bus_region region;
468 : struct resource *res;
469 :
470 0 : res = child->resource[2];
471 0 : pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
472 0 : pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
473 0 : base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
474 0 : limit64 = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
475 :
476 0 : if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
477 : u32 mem_base_hi, mem_limit_hi;
478 :
479 0 : pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
480 0 : pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
481 :
482 : /*
483 : * Some bridges set the base > limit by default, and some
484 : * (broken) BIOSes do not initialize them. If we find
485 : * this, just assume they are not being used.
486 : */
487 0 : if (mem_base_hi <= mem_limit_hi) {
488 0 : base64 |= (u64) mem_base_hi << 32;
489 0 : limit64 |= (u64) mem_limit_hi << 32;
490 : }
491 : }
492 :
493 0 : base = (pci_bus_addr_t) base64;
494 0 : limit = (pci_bus_addr_t) limit64;
495 :
496 : if (base != base64) {
497 : pci_err(dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
498 : (unsigned long long) base64);
499 : return;
500 : }
501 :
502 0 : if (base <= limit) {
503 0 : res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
504 0 : IORESOURCE_MEM | IORESOURCE_PREFETCH;
505 0 : if (res->flags & PCI_PREF_RANGE_TYPE_64)
506 0 : res->flags |= IORESOURCE_MEM_64;
507 0 : region.start = base;
508 0 : region.end = limit + 0xfffff;
509 0 : pcibios_bus_to_resource(dev->bus, res, ®ion);
510 0 : pci_info(dev, " bridge window %pR\n", res);
511 : }
512 : }
513 :
514 0 : void pci_read_bridge_bases(struct pci_bus *child)
515 : {
516 0 : struct pci_dev *dev = child->self;
517 : struct resource *res;
518 : int i;
519 :
520 0 : if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */
521 : return;
522 :
523 0 : pci_info(dev, "PCI bridge to %pR%s\n",
524 : &child->busn_res,
525 : dev->transparent ? " (subtractive decode)" : "");
526 :
527 0 : pci_bus_remove_resources(child);
528 0 : for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
529 0 : child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
530 :
531 0 : pci_read_bridge_io(child);
532 0 : pci_read_bridge_mmio(child);
533 0 : pci_read_bridge_mmio_pref(child);
534 :
535 0 : if (dev->transparent) {
536 0 : pci_bus_for_each_resource(child->parent, res, i) {
537 0 : if (res && res->flags) {
538 0 : pci_bus_add_resource(child, res,
539 : PCI_SUBTRACTIVE_DECODE);
540 0 : pci_info(dev, " bridge window %pR (subtractive decode)\n",
541 : res);
542 : }
543 : }
544 : }
545 : }
546 :
547 0 : static struct pci_bus *pci_alloc_bus(struct pci_bus *parent)
548 : {
549 : struct pci_bus *b;
550 :
551 0 : b = kzalloc(sizeof(*b), GFP_KERNEL);
552 0 : if (!b)
553 : return NULL;
554 :
555 0 : INIT_LIST_HEAD(&b->node);
556 0 : INIT_LIST_HEAD(&b->children);
557 0 : INIT_LIST_HEAD(&b->devices);
558 0 : INIT_LIST_HEAD(&b->slots);
559 0 : INIT_LIST_HEAD(&b->resources);
560 0 : b->max_bus_speed = PCI_SPEED_UNKNOWN;
561 0 : b->cur_bus_speed = PCI_SPEED_UNKNOWN;
562 : #ifdef CONFIG_PCI_DOMAINS_GENERIC
563 : if (parent)
564 : b->domain_nr = parent->domain_nr;
565 : #endif
566 : return b;
567 : }
568 :
569 0 : static void pci_release_host_bridge_dev(struct device *dev)
570 : {
571 0 : struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
572 :
573 0 : if (bridge->release_fn)
574 0 : bridge->release_fn(bridge);
575 :
576 0 : pci_free_resource_list(&bridge->windows);
577 0 : pci_free_resource_list(&bridge->dma_ranges);
578 0 : kfree(bridge);
579 0 : }
580 :
581 : static void pci_init_host_bridge(struct pci_host_bridge *bridge)
582 : {
583 0 : INIT_LIST_HEAD(&bridge->windows);
584 0 : INIT_LIST_HEAD(&bridge->dma_ranges);
585 :
586 : /*
587 : * We assume we can manage these PCIe features. Some systems may
588 : * reserve these for use by the platform itself, e.g., an ACPI BIOS
589 : * may implement its own AER handling and use _OSC to prevent the
590 : * OS from interfering.
591 : */
592 0 : bridge->native_aer = 1;
593 0 : bridge->native_pcie_hotplug = 1;
594 0 : bridge->native_shpc_hotplug = 1;
595 0 : bridge->native_pme = 1;
596 0 : bridge->native_ltr = 1;
597 0 : bridge->native_dpc = 1;
598 0 : bridge->domain_nr = PCI_DOMAIN_NR_NOT_SET;
599 0 : bridge->native_cxl_error = 1;
600 :
601 0 : device_initialize(&bridge->dev);
602 : }
603 :
604 0 : struct pci_host_bridge *pci_alloc_host_bridge(size_t priv)
605 : {
606 : struct pci_host_bridge *bridge;
607 :
608 0 : bridge = kzalloc(sizeof(*bridge) + priv, GFP_KERNEL);
609 0 : if (!bridge)
610 : return NULL;
611 :
612 0 : pci_init_host_bridge(bridge);
613 0 : bridge->dev.release = pci_release_host_bridge_dev;
614 :
615 0 : return bridge;
616 : }
617 : EXPORT_SYMBOL(pci_alloc_host_bridge);
618 :
619 0 : static void devm_pci_alloc_host_bridge_release(void *data)
620 : {
621 0 : pci_free_host_bridge(data);
622 0 : }
623 :
624 0 : struct pci_host_bridge *devm_pci_alloc_host_bridge(struct device *dev,
625 : size_t priv)
626 : {
627 : int ret;
628 : struct pci_host_bridge *bridge;
629 :
630 0 : bridge = pci_alloc_host_bridge(priv);
631 0 : if (!bridge)
632 : return NULL;
633 :
634 0 : bridge->dev.parent = dev;
635 :
636 0 : ret = devm_add_action_or_reset(dev, devm_pci_alloc_host_bridge_release,
637 : bridge);
638 0 : if (ret)
639 : return NULL;
640 :
641 0 : ret = devm_of_pci_bridge_init(dev, bridge);
642 : if (ret)
643 : return NULL;
644 :
645 0 : return bridge;
646 : }
647 : EXPORT_SYMBOL(devm_pci_alloc_host_bridge);
648 :
649 0 : void pci_free_host_bridge(struct pci_host_bridge *bridge)
650 : {
651 0 : put_device(&bridge->dev);
652 0 : }
653 : EXPORT_SYMBOL(pci_free_host_bridge);
654 :
655 : /* Indexed by PCI_X_SSTATUS_FREQ (secondary bus mode and frequency) */
656 : static const unsigned char pcix_bus_speed[] = {
657 : PCI_SPEED_UNKNOWN, /* 0 */
658 : PCI_SPEED_66MHz_PCIX, /* 1 */
659 : PCI_SPEED_100MHz_PCIX, /* 2 */
660 : PCI_SPEED_133MHz_PCIX, /* 3 */
661 : PCI_SPEED_UNKNOWN, /* 4 */
662 : PCI_SPEED_66MHz_PCIX_ECC, /* 5 */
663 : PCI_SPEED_100MHz_PCIX_ECC, /* 6 */
664 : PCI_SPEED_133MHz_PCIX_ECC, /* 7 */
665 : PCI_SPEED_UNKNOWN, /* 8 */
666 : PCI_SPEED_66MHz_PCIX_266, /* 9 */
667 : PCI_SPEED_100MHz_PCIX_266, /* A */
668 : PCI_SPEED_133MHz_PCIX_266, /* B */
669 : PCI_SPEED_UNKNOWN, /* C */
670 : PCI_SPEED_66MHz_PCIX_533, /* D */
671 : PCI_SPEED_100MHz_PCIX_533, /* E */
672 : PCI_SPEED_133MHz_PCIX_533 /* F */
673 : };
674 :
675 : /* Indexed by PCI_EXP_LNKCAP_SLS, PCI_EXP_LNKSTA_CLS */
676 : const unsigned char pcie_link_speed[] = {
677 : PCI_SPEED_UNKNOWN, /* 0 */
678 : PCIE_SPEED_2_5GT, /* 1 */
679 : PCIE_SPEED_5_0GT, /* 2 */
680 : PCIE_SPEED_8_0GT, /* 3 */
681 : PCIE_SPEED_16_0GT, /* 4 */
682 : PCIE_SPEED_32_0GT, /* 5 */
683 : PCIE_SPEED_64_0GT, /* 6 */
684 : PCI_SPEED_UNKNOWN, /* 7 */
685 : PCI_SPEED_UNKNOWN, /* 8 */
686 : PCI_SPEED_UNKNOWN, /* 9 */
687 : PCI_SPEED_UNKNOWN, /* A */
688 : PCI_SPEED_UNKNOWN, /* B */
689 : PCI_SPEED_UNKNOWN, /* C */
690 : PCI_SPEED_UNKNOWN, /* D */
691 : PCI_SPEED_UNKNOWN, /* E */
692 : PCI_SPEED_UNKNOWN /* F */
693 : };
694 : EXPORT_SYMBOL_GPL(pcie_link_speed);
695 :
696 0 : const char *pci_speed_string(enum pci_bus_speed speed)
697 : {
698 : /* Indexed by the pci_bus_speed enum */
699 : static const char *speed_strings[] = {
700 : "33 MHz PCI", /* 0x00 */
701 : "66 MHz PCI", /* 0x01 */
702 : "66 MHz PCI-X", /* 0x02 */
703 : "100 MHz PCI-X", /* 0x03 */
704 : "133 MHz PCI-X", /* 0x04 */
705 : NULL, /* 0x05 */
706 : NULL, /* 0x06 */
707 : NULL, /* 0x07 */
708 : NULL, /* 0x08 */
709 : "66 MHz PCI-X 266", /* 0x09 */
710 : "100 MHz PCI-X 266", /* 0x0a */
711 : "133 MHz PCI-X 266", /* 0x0b */
712 : "Unknown AGP", /* 0x0c */
713 : "1x AGP", /* 0x0d */
714 : "2x AGP", /* 0x0e */
715 : "4x AGP", /* 0x0f */
716 : "8x AGP", /* 0x10 */
717 : "66 MHz PCI-X 533", /* 0x11 */
718 : "100 MHz PCI-X 533", /* 0x12 */
719 : "133 MHz PCI-X 533", /* 0x13 */
720 : "2.5 GT/s PCIe", /* 0x14 */
721 : "5.0 GT/s PCIe", /* 0x15 */
722 : "8.0 GT/s PCIe", /* 0x16 */
723 : "16.0 GT/s PCIe", /* 0x17 */
724 : "32.0 GT/s PCIe", /* 0x18 */
725 : "64.0 GT/s PCIe", /* 0x19 */
726 : };
727 :
728 0 : if (speed < ARRAY_SIZE(speed_strings))
729 0 : return speed_strings[speed];
730 : return "Unknown";
731 : }
732 : EXPORT_SYMBOL_GPL(pci_speed_string);
733 :
734 0 : void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
735 : {
736 0 : bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS];
737 0 : }
738 : EXPORT_SYMBOL_GPL(pcie_update_link_speed);
739 :
740 : static unsigned char agp_speeds[] = {
741 : AGP_UNKNOWN,
742 : AGP_1X,
743 : AGP_2X,
744 : AGP_4X,
745 : AGP_8X
746 : };
747 :
748 : static enum pci_bus_speed agp_speed(int agp3, int agpstat)
749 : {
750 0 : int index = 0;
751 :
752 0 : if (agpstat & 4)
753 : index = 3;
754 0 : else if (agpstat & 2)
755 : index = 2;
756 0 : else if (agpstat & 1)
757 : index = 1;
758 : else
759 : goto out;
760 :
761 0 : if (agp3) {
762 0 : index += 2;
763 0 : if (index == 5)
764 0 : index = 0;
765 : }
766 :
767 : out:
768 0 : return agp_speeds[index];
769 : }
770 :
771 0 : static void pci_set_bus_speed(struct pci_bus *bus)
772 : {
773 0 : struct pci_dev *bridge = bus->self;
774 : int pos;
775 :
776 0 : pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
777 0 : if (!pos)
778 0 : pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
779 0 : if (pos) {
780 : u32 agpstat, agpcmd;
781 :
782 0 : pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
783 0 : bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
784 :
785 0 : pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
786 0 : bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
787 : }
788 :
789 0 : pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
790 0 : if (pos) {
791 : u16 status;
792 : enum pci_bus_speed max;
793 :
794 0 : pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
795 : &status);
796 :
797 0 : if (status & PCI_X_SSTATUS_533MHZ) {
798 : max = PCI_SPEED_133MHz_PCIX_533;
799 0 : } else if (status & PCI_X_SSTATUS_266MHZ) {
800 : max = PCI_SPEED_133MHz_PCIX_266;
801 0 : } else if (status & PCI_X_SSTATUS_133MHZ) {
802 0 : if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2)
803 : max = PCI_SPEED_133MHz_PCIX_ECC;
804 : else
805 0 : max = PCI_SPEED_133MHz_PCIX;
806 : } else {
807 : max = PCI_SPEED_66MHz_PCIX;
808 : }
809 :
810 0 : bus->max_bus_speed = max;
811 0 : bus->cur_bus_speed = pcix_bus_speed[
812 0 : (status & PCI_X_SSTATUS_FREQ) >> 6];
813 :
814 : return;
815 : }
816 :
817 0 : if (pci_is_pcie(bridge)) {
818 : u32 linkcap;
819 : u16 linksta;
820 :
821 0 : pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
822 0 : bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
823 0 : bridge->link_active_reporting = !!(linkcap & PCI_EXP_LNKCAP_DLLLARC);
824 :
825 0 : pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
826 0 : pcie_update_link_speed(bus, linksta);
827 : }
828 : }
829 :
830 0 : static struct irq_domain *pci_host_bridge_msi_domain(struct pci_bus *bus)
831 : {
832 : struct irq_domain *d;
833 :
834 : /* If the host bridge driver sets a MSI domain of the bridge, use it */
835 0 : d = dev_get_msi_domain(bus->bridge);
836 :
837 : /*
838 : * Any firmware interface that can resolve the msi_domain
839 : * should be called from here.
840 : */
841 0 : if (!d)
842 0 : d = pci_host_bridge_of_msi_domain(bus);
843 0 : if (!d)
844 0 : d = pci_host_bridge_acpi_msi_domain(bus);
845 :
846 : /*
847 : * If no IRQ domain was found via the OF tree, try looking it up
848 : * directly through the fwnode_handle.
849 : */
850 0 : if (!d) {
851 0 : struct fwnode_handle *fwnode = pci_root_bus_fwnode(bus);
852 :
853 0 : if (fwnode)
854 0 : d = irq_find_matching_fwnode(fwnode,
855 : DOMAIN_BUS_PCI_MSI);
856 : }
857 :
858 0 : return d;
859 : }
860 :
861 0 : static void pci_set_bus_msi_domain(struct pci_bus *bus)
862 : {
863 : struct irq_domain *d;
864 : struct pci_bus *b;
865 :
866 : /*
867 : * The bus can be a root bus, a subordinate bus, or a virtual bus
868 : * created by an SR-IOV device. Walk up to the first bridge device
869 : * found or derive the domain from the host bridge.
870 : */
871 0 : for (b = bus, d = NULL; !d && !pci_is_root_bus(b); b = b->parent) {
872 0 : if (b->self)
873 0 : d = dev_get_msi_domain(&b->self->dev);
874 : }
875 :
876 0 : if (!d)
877 0 : d = pci_host_bridge_msi_domain(b);
878 :
879 0 : dev_set_msi_domain(&bus->dev, d);
880 0 : }
881 :
882 0 : static int pci_register_host_bridge(struct pci_host_bridge *bridge)
883 : {
884 0 : struct device *parent = bridge->dev.parent;
885 : struct resource_entry *window, *next, *n;
886 : struct pci_bus *bus, *b;
887 : resource_size_t offset, next_offset;
888 0 : LIST_HEAD(resources);
889 : struct resource *res, *next_res;
890 : char addr[64], *fmt;
891 : const char *name;
892 : int err;
893 :
894 0 : bus = pci_alloc_bus(NULL);
895 0 : if (!bus)
896 : return -ENOMEM;
897 :
898 0 : bridge->bus = bus;
899 :
900 0 : bus->sysdata = bridge->sysdata;
901 0 : bus->ops = bridge->ops;
902 0 : bus->number = bus->busn_res.start = bridge->busnr;
903 : #ifdef CONFIG_PCI_DOMAINS_GENERIC
904 : if (bridge->domain_nr == PCI_DOMAIN_NR_NOT_SET)
905 : bus->domain_nr = pci_bus_find_domain_nr(bus, parent);
906 : else
907 : bus->domain_nr = bridge->domain_nr;
908 : if (bus->domain_nr < 0) {
909 : err = bus->domain_nr;
910 : goto free;
911 : }
912 : #endif
913 :
914 0 : b = pci_find_bus(pci_domain_nr(bus), bridge->busnr);
915 0 : if (b) {
916 : /* Ignore it if we already got here via a different bridge */
917 : dev_dbg(&b->dev, "bus already known\n");
918 : err = -EEXIST;
919 : goto free;
920 : }
921 :
922 0 : dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(bus),
923 : bridge->busnr);
924 :
925 0 : err = pcibios_root_bridge_prepare(bridge);
926 0 : if (err)
927 : goto free;
928 :
929 : /* Temporarily move resources off the list */
930 0 : list_splice_init(&bridge->windows, &resources);
931 0 : err = device_add(&bridge->dev);
932 0 : if (err) {
933 0 : put_device(&bridge->dev);
934 0 : goto free;
935 : }
936 0 : bus->bridge = get_device(&bridge->dev);
937 0 : device_enable_async_suspend(bus->bridge);
938 0 : pci_set_bus_of_node(bus);
939 0 : pci_set_bus_msi_domain(bus);
940 0 : if (bridge->msi_domain && !dev_get_msi_domain(&bus->dev) &&
941 0 : !pci_host_of_has_msi_map(parent))
942 0 : bus->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
943 :
944 : if (!parent)
945 : set_dev_node(bus->bridge, pcibus_to_node(bus));
946 :
947 0 : bus->dev.class = &pcibus_class;
948 0 : bus->dev.parent = bus->bridge;
949 :
950 0 : dev_set_name(&bus->dev, "%04x:%02x", pci_domain_nr(bus), bus->number);
951 0 : name = dev_name(&bus->dev);
952 :
953 0 : err = device_register(&bus->dev);
954 0 : if (err)
955 : goto unregister;
956 :
957 0 : pcibios_add_bus(bus);
958 :
959 0 : if (bus->ops->add_bus) {
960 0 : err = bus->ops->add_bus(bus);
961 0 : if (WARN_ON(err < 0))
962 0 : dev_err(&bus->dev, "failed to add bus: %d\n", err);
963 : }
964 :
965 : /* Create legacy_io and legacy_mem files for this bus */
966 0 : pci_create_legacy_files(bus);
967 :
968 0 : if (parent)
969 0 : dev_info(parent, "PCI host bridge to bus %s\n", name);
970 : else
971 0 : pr_info("PCI host bridge to bus %s\n", name);
972 :
973 : if (nr_node_ids > 1 && pcibus_to_node(bus) == NUMA_NO_NODE)
974 : dev_warn(&bus->dev, "Unknown NUMA node; performance will be reduced\n");
975 :
976 : /* Coalesce contiguous windows */
977 0 : resource_list_for_each_entry_safe(window, n, &resources) {
978 0 : if (list_is_last(&window->node, &resources))
979 : break;
980 :
981 0 : next = list_next_entry(window, node);
982 0 : offset = window->offset;
983 0 : res = window->res;
984 0 : next_offset = next->offset;
985 0 : next_res = next->res;
986 :
987 0 : if (res->flags != next_res->flags || offset != next_offset)
988 0 : continue;
989 :
990 0 : if (res->end + 1 == next_res->start) {
991 0 : next_res->start = res->start;
992 0 : res->flags = res->start = res->end = 0;
993 : }
994 : }
995 :
996 : /* Add initial resources to the bus */
997 0 : resource_list_for_each_entry_safe(window, n, &resources) {
998 0 : offset = window->offset;
999 0 : res = window->res;
1000 0 : if (!res->flags && !res->start && !res->end)
1001 0 : continue;
1002 :
1003 0 : list_move_tail(&window->node, &bridge->windows);
1004 :
1005 0 : if (res->flags & IORESOURCE_BUS)
1006 0 : pci_bus_insert_busn_res(bus, bus->number, res->end);
1007 : else
1008 0 : pci_bus_add_resource(bus, res, 0);
1009 :
1010 0 : if (offset) {
1011 0 : if (resource_type(res) == IORESOURCE_IO)
1012 : fmt = " (bus address [%#06llx-%#06llx])";
1013 : else
1014 0 : fmt = " (bus address [%#010llx-%#010llx])";
1015 :
1016 0 : snprintf(addr, sizeof(addr), fmt,
1017 0 : (unsigned long long)(res->start - offset),
1018 0 : (unsigned long long)(res->end - offset));
1019 : } else
1020 0 : addr[0] = '\0';
1021 :
1022 0 : dev_info(&bus->dev, "root bus resource %pR%s\n", res, addr);
1023 : }
1024 :
1025 0 : down_write(&pci_bus_sem);
1026 0 : list_add_tail(&bus->node, &pci_root_buses);
1027 0 : up_write(&pci_bus_sem);
1028 :
1029 0 : return 0;
1030 :
1031 : unregister:
1032 0 : put_device(&bridge->dev);
1033 0 : device_del(&bridge->dev);
1034 :
1035 : free:
1036 : #ifdef CONFIG_PCI_DOMAINS_GENERIC
1037 : pci_bus_release_domain_nr(bus, parent);
1038 : #endif
1039 0 : kfree(bus);
1040 0 : return err;
1041 : }
1042 :
1043 0 : static bool pci_bridge_child_ext_cfg_accessible(struct pci_dev *bridge)
1044 : {
1045 : int pos;
1046 : u32 status;
1047 :
1048 : /*
1049 : * If extended config space isn't accessible on a bridge's primary
1050 : * bus, we certainly can't access it on the secondary bus.
1051 : */
1052 0 : if (bridge->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG)
1053 : return false;
1054 :
1055 : /*
1056 : * PCIe Root Ports and switch ports are PCIe on both sides, so if
1057 : * extended config space is accessible on the primary, it's also
1058 : * accessible on the secondary.
1059 : */
1060 0 : if (pci_is_pcie(bridge) &&
1061 0 : (pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT ||
1062 0 : pci_pcie_type(bridge) == PCI_EXP_TYPE_UPSTREAM ||
1063 0 : pci_pcie_type(bridge) == PCI_EXP_TYPE_DOWNSTREAM))
1064 : return true;
1065 :
1066 : /*
1067 : * For the other bridge types:
1068 : * - PCI-to-PCI bridges
1069 : * - PCIe-to-PCI/PCI-X forward bridges
1070 : * - PCI/PCI-X-to-PCIe reverse bridges
1071 : * extended config space on the secondary side is only accessible
1072 : * if the bridge supports PCI-X Mode 2.
1073 : */
1074 0 : pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
1075 0 : if (!pos)
1076 : return false;
1077 :
1078 0 : pci_read_config_dword(bridge, pos + PCI_X_STATUS, &status);
1079 0 : return status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ);
1080 : }
1081 :
1082 0 : static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
1083 : struct pci_dev *bridge, int busnr)
1084 : {
1085 : struct pci_bus *child;
1086 : struct pci_host_bridge *host;
1087 : int i;
1088 : int ret;
1089 :
1090 : /* Allocate a new bus and inherit stuff from the parent */
1091 0 : child = pci_alloc_bus(parent);
1092 0 : if (!child)
1093 : return NULL;
1094 :
1095 0 : child->parent = parent;
1096 0 : child->sysdata = parent->sysdata;
1097 0 : child->bus_flags = parent->bus_flags;
1098 :
1099 0 : host = pci_find_host_bridge(parent);
1100 0 : if (host->child_ops)
1101 0 : child->ops = host->child_ops;
1102 : else
1103 0 : child->ops = parent->ops;
1104 :
1105 : /*
1106 : * Initialize some portions of the bus device, but don't register
1107 : * it now as the parent is not properly set up yet.
1108 : */
1109 0 : child->dev.class = &pcibus_class;
1110 0 : dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
1111 :
1112 : /* Set up the primary, secondary and subordinate bus numbers */
1113 0 : child->number = child->busn_res.start = busnr;
1114 0 : child->primary = parent->busn_res.start;
1115 0 : child->busn_res.end = 0xff;
1116 :
1117 0 : if (!bridge) {
1118 0 : child->dev.parent = parent->bridge;
1119 0 : goto add_dev;
1120 : }
1121 :
1122 0 : child->self = bridge;
1123 0 : child->bridge = get_device(&bridge->dev);
1124 0 : child->dev.parent = child->bridge;
1125 0 : pci_set_bus_of_node(child);
1126 0 : pci_set_bus_speed(child);
1127 :
1128 : /*
1129 : * Check whether extended config space is accessible on the child
1130 : * bus. Note that we currently assume it is always accessible on
1131 : * the root bus.
1132 : */
1133 0 : if (!pci_bridge_child_ext_cfg_accessible(bridge)) {
1134 0 : child->bus_flags |= PCI_BUS_FLAGS_NO_EXTCFG;
1135 0 : pci_info(child, "extended config space not accessible\n");
1136 : }
1137 :
1138 : /* Set up default resource pointers and names */
1139 0 : for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
1140 0 : child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
1141 0 : child->resource[i]->name = child->name;
1142 : }
1143 0 : bridge->subordinate = child;
1144 :
1145 : add_dev:
1146 0 : pci_set_bus_msi_domain(child);
1147 0 : ret = device_register(&child->dev);
1148 0 : WARN_ON(ret < 0);
1149 :
1150 0 : pcibios_add_bus(child);
1151 :
1152 0 : if (child->ops->add_bus) {
1153 0 : ret = child->ops->add_bus(child);
1154 0 : if (WARN_ON(ret < 0))
1155 0 : dev_err(&child->dev, "failed to add bus: %d\n", ret);
1156 : }
1157 :
1158 : /* Create legacy_io and legacy_mem files for this bus */
1159 : pci_create_legacy_files(child);
1160 :
1161 : return child;
1162 : }
1163 :
1164 0 : struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev,
1165 : int busnr)
1166 : {
1167 : struct pci_bus *child;
1168 :
1169 0 : child = pci_alloc_child_bus(parent, dev, busnr);
1170 0 : if (child) {
1171 0 : down_write(&pci_bus_sem);
1172 0 : list_add_tail(&child->node, &parent->children);
1173 0 : up_write(&pci_bus_sem);
1174 : }
1175 0 : return child;
1176 : }
1177 : EXPORT_SYMBOL(pci_add_new_bus);
1178 :
1179 0 : static void pci_enable_crs(struct pci_dev *pdev)
1180 : {
1181 0 : u16 root_cap = 0;
1182 :
1183 : /* Enable CRS Software Visibility if supported */
1184 0 : pcie_capability_read_word(pdev, PCI_EXP_RTCAP, &root_cap);
1185 0 : if (root_cap & PCI_EXP_RTCAP_CRSVIS)
1186 : pcie_capability_set_word(pdev, PCI_EXP_RTCTL,
1187 : PCI_EXP_RTCTL_CRSSVE);
1188 0 : }
1189 :
1190 : static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
1191 : unsigned int available_buses);
1192 : /**
1193 : * pci_ea_fixed_busnrs() - Read fixed Secondary and Subordinate bus
1194 : * numbers from EA capability.
1195 : * @dev: Bridge
1196 : * @sec: updated with secondary bus number from EA
1197 : * @sub: updated with subordinate bus number from EA
1198 : *
1199 : * If @dev is a bridge with EA capability that specifies valid secondary
1200 : * and subordinate bus numbers, return true with the bus numbers in @sec
1201 : * and @sub. Otherwise return false.
1202 : */
1203 0 : static bool pci_ea_fixed_busnrs(struct pci_dev *dev, u8 *sec, u8 *sub)
1204 : {
1205 : int ea, offset;
1206 : u32 dw;
1207 : u8 ea_sec, ea_sub;
1208 :
1209 0 : if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE)
1210 : return false;
1211 :
1212 : /* find PCI EA capability in list */
1213 0 : ea = pci_find_capability(dev, PCI_CAP_ID_EA);
1214 0 : if (!ea)
1215 : return false;
1216 :
1217 0 : offset = ea + PCI_EA_FIRST_ENT;
1218 0 : pci_read_config_dword(dev, offset, &dw);
1219 0 : ea_sec = dw & PCI_EA_SEC_BUS_MASK;
1220 0 : ea_sub = (dw & PCI_EA_SUB_BUS_MASK) >> PCI_EA_SUB_BUS_SHIFT;
1221 0 : if (ea_sec == 0 || ea_sub < ea_sec)
1222 : return false;
1223 :
1224 0 : *sec = ea_sec;
1225 0 : *sub = ea_sub;
1226 0 : return true;
1227 : }
1228 :
1229 : /*
1230 : * pci_scan_bridge_extend() - Scan buses behind a bridge
1231 : * @bus: Parent bus the bridge is on
1232 : * @dev: Bridge itself
1233 : * @max: Starting subordinate number of buses behind this bridge
1234 : * @available_buses: Total number of buses available for this bridge and
1235 : * the devices below. After the minimal bus space has
1236 : * been allocated the remaining buses will be
1237 : * distributed equally between hotplug-capable bridges.
1238 : * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges
1239 : * that need to be reconfigured.
1240 : *
1241 : * If it's a bridge, configure it and scan the bus behind it.
1242 : * For CardBus bridges, we don't scan behind as the devices will
1243 : * be handled by the bridge driver itself.
1244 : *
1245 : * We need to process bridges in two passes -- first we scan those
1246 : * already configured by the BIOS and after we are done with all of
1247 : * them, we proceed to assigning numbers to the remaining buses in
1248 : * order to avoid overlaps between old and new bus numbers.
1249 : *
1250 : * Return: New subordinate number covering all buses behind this bridge.
1251 : */
1252 0 : static int pci_scan_bridge_extend(struct pci_bus *bus, struct pci_dev *dev,
1253 : int max, unsigned int available_buses,
1254 : int pass)
1255 : {
1256 : struct pci_bus *child;
1257 0 : int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
1258 0 : u32 buses, i, j = 0;
1259 : u16 bctl;
1260 : u8 primary, secondary, subordinate;
1261 0 : int broken = 0;
1262 : bool fixed_buses;
1263 : u8 fixed_sec, fixed_sub;
1264 : int next_busnr;
1265 :
1266 : /*
1267 : * Make sure the bridge is powered on to be able to access config
1268 : * space of devices below it.
1269 : */
1270 0 : pm_runtime_get_sync(&dev->dev);
1271 :
1272 0 : pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
1273 0 : primary = buses & 0xFF;
1274 0 : secondary = (buses >> 8) & 0xFF;
1275 0 : subordinate = (buses >> 16) & 0xFF;
1276 :
1277 : pci_dbg(dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
1278 : secondary, subordinate, pass);
1279 :
1280 0 : if (!primary && (primary != bus->number) && secondary && subordinate) {
1281 0 : pci_warn(dev, "Primary bus is hard wired to 0\n");
1282 0 : primary = bus->number;
1283 : }
1284 :
1285 : /* Check if setup is sensible at all */
1286 0 : if (!pass &&
1287 0 : (primary != bus->number || secondary <= bus->number ||
1288 : secondary > subordinate)) {
1289 0 : pci_info(dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
1290 : secondary, subordinate);
1291 0 : broken = 1;
1292 : }
1293 :
1294 : /*
1295 : * Disable Master-Abort Mode during probing to avoid reporting of
1296 : * bus errors in some architectures.
1297 : */
1298 0 : pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
1299 0 : pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
1300 0 : bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
1301 :
1302 0 : pci_enable_crs(dev);
1303 :
1304 : if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
1305 : !is_cardbus && !broken) {
1306 : unsigned int cmax, buses;
1307 :
1308 : /*
1309 : * Bus already configured by firmware, process it in the
1310 : * first pass and just note the configuration.
1311 : */
1312 : if (pass)
1313 : goto out;
1314 :
1315 : /*
1316 : * The bus might already exist for two reasons: Either we
1317 : * are rescanning the bus or the bus is reachable through
1318 : * more than one bridge. The second case can happen with
1319 : * the i450NX chipset.
1320 : */
1321 : child = pci_find_bus(pci_domain_nr(bus), secondary);
1322 : if (!child) {
1323 : child = pci_add_new_bus(bus, dev, secondary);
1324 : if (!child)
1325 : goto out;
1326 : child->primary = primary;
1327 : pci_bus_insert_busn_res(child, secondary, subordinate);
1328 : child->bridge_ctl = bctl;
1329 : }
1330 :
1331 : buses = subordinate - secondary;
1332 : cmax = pci_scan_child_bus_extend(child, buses);
1333 : if (cmax > subordinate)
1334 : pci_warn(dev, "bridge has subordinate %02x but max busn %02x\n",
1335 : subordinate, cmax);
1336 :
1337 : /* Subordinate should equal child->busn_res.end */
1338 : if (subordinate > max)
1339 : max = subordinate;
1340 : } else {
1341 :
1342 : /*
1343 : * We need to assign a number to this bus which we always
1344 : * do in the second pass.
1345 : */
1346 0 : if (!pass) {
1347 : if (pcibios_assign_all_busses() || broken || is_cardbus)
1348 :
1349 : /*
1350 : * Temporarily disable forwarding of the
1351 : * configuration cycles on all bridges in
1352 : * this bus segment to avoid possible
1353 : * conflicts in the second pass between two
1354 : * bridges programmed with overlapping bus
1355 : * ranges.
1356 : */
1357 0 : pci_write_config_dword(dev, PCI_PRIMARY_BUS,
1358 : buses & ~0xffffff);
1359 0 : goto out;
1360 : }
1361 :
1362 : /* Clear errors */
1363 0 : pci_write_config_word(dev, PCI_STATUS, 0xffff);
1364 :
1365 : /* Read bus numbers from EA Capability (if present) */
1366 0 : fixed_buses = pci_ea_fixed_busnrs(dev, &fixed_sec, &fixed_sub);
1367 0 : if (fixed_buses)
1368 0 : next_busnr = fixed_sec;
1369 : else
1370 0 : next_busnr = max + 1;
1371 :
1372 : /*
1373 : * Prevent assigning a bus number that already exists.
1374 : * This can happen when a bridge is hot-plugged, so in this
1375 : * case we only re-scan this bus.
1376 : */
1377 0 : child = pci_find_bus(pci_domain_nr(bus), next_busnr);
1378 0 : if (!child) {
1379 0 : child = pci_add_new_bus(bus, dev, next_busnr);
1380 0 : if (!child)
1381 : goto out;
1382 0 : pci_bus_insert_busn_res(child, next_busnr,
1383 0 : bus->busn_res.end);
1384 : }
1385 0 : max++;
1386 0 : if (available_buses)
1387 0 : available_buses--;
1388 :
1389 0 : buses = (buses & 0xff000000)
1390 0 : | ((unsigned int)(child->primary) << 0)
1391 0 : | ((unsigned int)(child->busn_res.start) << 8)
1392 0 : | ((unsigned int)(child->busn_res.end) << 16);
1393 :
1394 : /*
1395 : * yenta.c forces a secondary latency timer of 176.
1396 : * Copy that behaviour here.
1397 : */
1398 0 : if (is_cardbus) {
1399 0 : buses &= ~0xff000000;
1400 0 : buses |= CARDBUS_LATENCY_TIMER << 24;
1401 : }
1402 :
1403 : /* We need to blast all three values with a single write */
1404 0 : pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
1405 :
1406 0 : if (!is_cardbus) {
1407 0 : child->bridge_ctl = bctl;
1408 0 : max = pci_scan_child_bus_extend(child, available_buses);
1409 : } else {
1410 :
1411 : /*
1412 : * For CardBus bridges, we leave 4 bus numbers as
1413 : * cards with a PCI-to-PCI bridge can be inserted
1414 : * later.
1415 : */
1416 0 : for (i = 0; i < CARDBUS_RESERVE_BUSNR; i++) {
1417 0 : struct pci_bus *parent = bus;
1418 0 : if (pci_find_bus(pci_domain_nr(bus),
1419 0 : max+i+1))
1420 : break;
1421 0 : while (parent->parent) {
1422 : if ((!pcibios_assign_all_busses()) &&
1423 : (parent->busn_res.end > max) &&
1424 : (parent->busn_res.end <= max+i)) {
1425 : j = 1;
1426 : }
1427 : parent = parent->parent;
1428 : }
1429 : if (j) {
1430 :
1431 : /*
1432 : * Often, there are two CardBus
1433 : * bridges -- try to leave one
1434 : * valid bus number for each one.
1435 : */
1436 : i /= 2;
1437 : break;
1438 : }
1439 : }
1440 0 : max += i;
1441 : }
1442 :
1443 : /*
1444 : * Set subordinate bus number to its real value.
1445 : * If fixed subordinate bus number exists from EA
1446 : * capability then use it.
1447 : */
1448 0 : if (fixed_buses)
1449 0 : max = fixed_sub;
1450 0 : pci_bus_update_busn_res_end(child, max);
1451 0 : pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
1452 : }
1453 :
1454 0 : sprintf(child->name,
1455 : (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
1456 0 : pci_domain_nr(bus), child->number);
1457 :
1458 : /* Check that all devices are accessible */
1459 0 : while (bus->parent) {
1460 0 : if ((child->busn_res.end > bus->busn_res.end) ||
1461 0 : (child->number > bus->busn_res.end) ||
1462 0 : (child->number < bus->number) ||
1463 0 : (child->busn_res.end < bus->number)) {
1464 0 : dev_info(&dev->dev, "devices behind bridge are unusable because %pR cannot be assigned for them\n",
1465 : &child->busn_res);
1466 0 : break;
1467 : }
1468 : bus = bus->parent;
1469 : }
1470 :
1471 : out:
1472 0 : pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
1473 :
1474 0 : pm_runtime_put(&dev->dev);
1475 :
1476 0 : return max;
1477 : }
1478 :
1479 : /*
1480 : * pci_scan_bridge() - Scan buses behind a bridge
1481 : * @bus: Parent bus the bridge is on
1482 : * @dev: Bridge itself
1483 : * @max: Starting subordinate number of buses behind this bridge
1484 : * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges
1485 : * that need to be reconfigured.
1486 : *
1487 : * If it's a bridge, configure it and scan the bus behind it.
1488 : * For CardBus bridges, we don't scan behind as the devices will
1489 : * be handled by the bridge driver itself.
1490 : *
1491 : * We need to process bridges in two passes -- first we scan those
1492 : * already configured by the BIOS and after we are done with all of
1493 : * them, we proceed to assigning numbers to the remaining buses in
1494 : * order to avoid overlaps between old and new bus numbers.
1495 : *
1496 : * Return: New subordinate number covering all buses behind this bridge.
1497 : */
1498 0 : int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
1499 : {
1500 0 : return pci_scan_bridge_extend(bus, dev, max, 0, pass);
1501 : }
1502 : EXPORT_SYMBOL(pci_scan_bridge);
1503 :
1504 : /*
1505 : * Read interrupt line and base address registers.
1506 : * The architecture-dependent code can tweak these, of course.
1507 : */
1508 0 : static void pci_read_irq(struct pci_dev *dev)
1509 : {
1510 : unsigned char irq;
1511 :
1512 : /* VFs are not allowed to use INTx, so skip the config reads */
1513 0 : if (dev->is_virtfn) {
1514 0 : dev->pin = 0;
1515 0 : dev->irq = 0;
1516 0 : return;
1517 : }
1518 :
1519 0 : pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
1520 0 : dev->pin = irq;
1521 0 : if (irq)
1522 0 : pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
1523 0 : dev->irq = irq;
1524 : }
1525 :
1526 0 : void set_pcie_port_type(struct pci_dev *pdev)
1527 : {
1528 : int pos;
1529 : u16 reg16;
1530 : int type;
1531 : struct pci_dev *parent;
1532 :
1533 0 : pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
1534 0 : if (!pos)
1535 0 : return;
1536 :
1537 0 : pdev->pcie_cap = pos;
1538 0 : pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16);
1539 0 : pdev->pcie_flags_reg = reg16;
1540 0 : pci_read_config_dword(pdev, pos + PCI_EXP_DEVCAP, &pdev->devcap);
1541 0 : pdev->pcie_mpss = FIELD_GET(PCI_EXP_DEVCAP_PAYLOAD, pdev->devcap);
1542 :
1543 0 : parent = pci_upstream_bridge(pdev);
1544 0 : if (!parent)
1545 : return;
1546 :
1547 : /*
1548 : * Some systems do not identify their upstream/downstream ports
1549 : * correctly so detect impossible configurations here and correct
1550 : * the port type accordingly.
1551 : */
1552 0 : type = pci_pcie_type(pdev);
1553 0 : if (type == PCI_EXP_TYPE_DOWNSTREAM) {
1554 : /*
1555 : * If pdev claims to be downstream port but the parent
1556 : * device is also downstream port assume pdev is actually
1557 : * upstream port.
1558 : */
1559 0 : if (pcie_downstream_port(parent)) {
1560 0 : pci_info(pdev, "claims to be downstream port but is acting as upstream port, correcting type\n");
1561 0 : pdev->pcie_flags_reg &= ~PCI_EXP_FLAGS_TYPE;
1562 0 : pdev->pcie_flags_reg |= PCI_EXP_TYPE_UPSTREAM;
1563 : }
1564 0 : } else if (type == PCI_EXP_TYPE_UPSTREAM) {
1565 : /*
1566 : * If pdev claims to be upstream port but the parent
1567 : * device is also upstream port assume pdev is actually
1568 : * downstream port.
1569 : */
1570 0 : if (pci_pcie_type(parent) == PCI_EXP_TYPE_UPSTREAM) {
1571 0 : pci_info(pdev, "claims to be upstream port but is acting as downstream port, correcting type\n");
1572 0 : pdev->pcie_flags_reg &= ~PCI_EXP_FLAGS_TYPE;
1573 0 : pdev->pcie_flags_reg |= PCI_EXP_TYPE_DOWNSTREAM;
1574 : }
1575 : }
1576 : }
1577 :
1578 0 : void set_pcie_hotplug_bridge(struct pci_dev *pdev)
1579 : {
1580 : u32 reg32;
1581 :
1582 0 : pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32);
1583 0 : if (reg32 & PCI_EXP_SLTCAP_HPC)
1584 0 : pdev->is_hotplug_bridge = 1;
1585 0 : }
1586 :
1587 : static void set_pcie_thunderbolt(struct pci_dev *dev)
1588 : {
1589 : u16 vsec;
1590 :
1591 : /* Is the device part of a Thunderbolt controller? */
1592 0 : vsec = pci_find_vsec_capability(dev, PCI_VENDOR_ID_INTEL, PCI_VSEC_ID_INTEL_TBT);
1593 0 : if (vsec)
1594 0 : dev->is_thunderbolt = 1;
1595 : }
1596 :
1597 : static void set_pcie_untrusted(struct pci_dev *dev)
1598 : {
1599 : struct pci_dev *parent;
1600 :
1601 : /*
1602 : * If the upstream bridge is untrusted we treat this device
1603 : * untrusted as well.
1604 : */
1605 0 : parent = pci_upstream_bridge(dev);
1606 0 : if (parent && (parent->untrusted || parent->external_facing))
1607 0 : dev->untrusted = true;
1608 : }
1609 :
1610 : static void pci_set_removable(struct pci_dev *dev)
1611 : {
1612 0 : struct pci_dev *parent = pci_upstream_bridge(dev);
1613 :
1614 : /*
1615 : * We (only) consider everything downstream from an external_facing
1616 : * device to be removable by the user. We're mainly concerned with
1617 : * consumer platforms with user accessible thunderbolt ports that are
1618 : * vulnerable to DMA attacks, and we expect those ports to be marked by
1619 : * the firmware as external_facing. Devices in traditional hotplug
1620 : * slots can technically be removed, but the expectation is that unless
1621 : * the port is marked with external_facing, such devices are less
1622 : * accessible to user / may not be removed by end user, and thus not
1623 : * exposed as "removable" to userspace.
1624 : */
1625 0 : if (parent &&
1626 0 : (parent->external_facing || dev_is_removable(&parent->dev)))
1627 0 : dev_set_removable(&dev->dev, DEVICE_REMOVABLE);
1628 : }
1629 :
1630 : /**
1631 : * pci_ext_cfg_is_aliased - Is ext config space just an alias of std config?
1632 : * @dev: PCI device
1633 : *
1634 : * PCI Express to PCI/PCI-X Bridge Specification, rev 1.0, 4.1.4 says that
1635 : * when forwarding a type1 configuration request the bridge must check that
1636 : * the extended register address field is zero. The bridge is not permitted
1637 : * to forward the transactions and must handle it as an Unsupported Request.
1638 : * Some bridges do not follow this rule and simply drop the extended register
1639 : * bits, resulting in the standard config space being aliased, every 256
1640 : * bytes across the entire configuration space. Test for this condition by
1641 : * comparing the first dword of each potential alias to the vendor/device ID.
1642 : * Known offenders:
1643 : * ASM1083/1085 PCIe-to-PCI Reversible Bridge (1b21:1080, rev 01 & 03)
1644 : * AMD/ATI SBx00 PCI to PCI Bridge (1002:4384, rev 40)
1645 : */
1646 0 : static bool pci_ext_cfg_is_aliased(struct pci_dev *dev)
1647 : {
1648 : #ifdef CONFIG_PCI_QUIRKS
1649 : int pos;
1650 : u32 header, tmp;
1651 :
1652 0 : pci_read_config_dword(dev, PCI_VENDOR_ID, &header);
1653 :
1654 0 : for (pos = PCI_CFG_SPACE_SIZE;
1655 0 : pos < PCI_CFG_SPACE_EXP_SIZE; pos += PCI_CFG_SPACE_SIZE) {
1656 0 : if (pci_read_config_dword(dev, pos, &tmp) != PCIBIOS_SUCCESSFUL
1657 0 : || header != tmp)
1658 : return false;
1659 : }
1660 :
1661 : return true;
1662 : #else
1663 : return false;
1664 : #endif
1665 : }
1666 :
1667 : /**
1668 : * pci_cfg_space_size_ext - Get the configuration space size of the PCI device
1669 : * @dev: PCI device
1670 : *
1671 : * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1672 : * have 4096 bytes. Even if the device is capable, that doesn't mean we can
1673 : * access it. Maybe we don't have a way to generate extended config space
1674 : * accesses, or the device is behind a reverse Express bridge. So we try
1675 : * reading the dword at 0x100 which must either be 0 or a valid extended
1676 : * capability header.
1677 : */
1678 0 : static int pci_cfg_space_size_ext(struct pci_dev *dev)
1679 : {
1680 : u32 status;
1681 0 : int pos = PCI_CFG_SPACE_SIZE;
1682 :
1683 0 : if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1684 : return PCI_CFG_SPACE_SIZE;
1685 0 : if (PCI_POSSIBLE_ERROR(status) || pci_ext_cfg_is_aliased(dev))
1686 : return PCI_CFG_SPACE_SIZE;
1687 :
1688 : return PCI_CFG_SPACE_EXP_SIZE;
1689 : }
1690 :
1691 0 : int pci_cfg_space_size(struct pci_dev *dev)
1692 : {
1693 : int pos;
1694 : u32 status;
1695 : u16 class;
1696 :
1697 : #ifdef CONFIG_PCI_IOV
1698 : /*
1699 : * Per the SR-IOV specification (rev 1.1, sec 3.5), VFs are required to
1700 : * implement a PCIe capability and therefore must implement extended
1701 : * config space. We can skip the NO_EXTCFG test below and the
1702 : * reachability/aliasing test in pci_cfg_space_size_ext() by virtue of
1703 : * the fact that the SR-IOV capability on the PF resides in extended
1704 : * config space and must be accessible and non-aliased to have enabled
1705 : * support for this VF. This is a micro performance optimization for
1706 : * systems supporting many VFs.
1707 : */
1708 : if (dev->is_virtfn)
1709 : return PCI_CFG_SPACE_EXP_SIZE;
1710 : #endif
1711 :
1712 0 : if (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG)
1713 : return PCI_CFG_SPACE_SIZE;
1714 :
1715 0 : class = dev->class >> 8;
1716 0 : if (class == PCI_CLASS_BRIDGE_HOST)
1717 0 : return pci_cfg_space_size_ext(dev);
1718 :
1719 0 : if (pci_is_pcie(dev))
1720 0 : return pci_cfg_space_size_ext(dev);
1721 :
1722 0 : pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1723 0 : if (!pos)
1724 : return PCI_CFG_SPACE_SIZE;
1725 :
1726 0 : pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1727 0 : if (status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ))
1728 0 : return pci_cfg_space_size_ext(dev);
1729 :
1730 : return PCI_CFG_SPACE_SIZE;
1731 : }
1732 :
1733 : static u32 pci_class(struct pci_dev *dev)
1734 : {
1735 : u32 class;
1736 :
1737 : #ifdef CONFIG_PCI_IOV
1738 : if (dev->is_virtfn)
1739 : return dev->physfn->sriov->class;
1740 : #endif
1741 0 : pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
1742 0 : return class;
1743 : }
1744 :
1745 : static void pci_subsystem_ids(struct pci_dev *dev, u16 *vendor, u16 *device)
1746 : {
1747 : #ifdef CONFIG_PCI_IOV
1748 : if (dev->is_virtfn) {
1749 : *vendor = dev->physfn->sriov->subsystem_vendor;
1750 : *device = dev->physfn->sriov->subsystem_device;
1751 : return;
1752 : }
1753 : #endif
1754 0 : pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, vendor);
1755 0 : pci_read_config_word(dev, PCI_SUBSYSTEM_ID, device);
1756 : }
1757 :
1758 : static u8 pci_hdr_type(struct pci_dev *dev)
1759 : {
1760 : u8 hdr_type;
1761 :
1762 : #ifdef CONFIG_PCI_IOV
1763 : if (dev->is_virtfn)
1764 : return dev->physfn->sriov->hdr_type;
1765 : #endif
1766 0 : pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type);
1767 0 : return hdr_type;
1768 : }
1769 :
1770 : #define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
1771 :
1772 : /**
1773 : * pci_intx_mask_broken - Test PCI_COMMAND_INTX_DISABLE writability
1774 : * @dev: PCI device
1775 : *
1776 : * Test whether PCI_COMMAND_INTX_DISABLE is writable for @dev. Check this
1777 : * at enumeration-time to avoid modifying PCI_COMMAND at run-time.
1778 : */
1779 0 : static int pci_intx_mask_broken(struct pci_dev *dev)
1780 : {
1781 : u16 orig, toggle, new;
1782 :
1783 0 : pci_read_config_word(dev, PCI_COMMAND, &orig);
1784 0 : toggle = orig ^ PCI_COMMAND_INTX_DISABLE;
1785 0 : pci_write_config_word(dev, PCI_COMMAND, toggle);
1786 0 : pci_read_config_word(dev, PCI_COMMAND, &new);
1787 :
1788 0 : pci_write_config_word(dev, PCI_COMMAND, orig);
1789 :
1790 : /*
1791 : * PCI_COMMAND_INTX_DISABLE was reserved and read-only prior to PCI
1792 : * r2.3, so strictly speaking, a device is not *broken* if it's not
1793 : * writable. But we'll live with the misnomer for now.
1794 : */
1795 0 : if (new != toggle)
1796 : return 1;
1797 0 : return 0;
1798 : }
1799 :
1800 0 : static void early_dump_pci_device(struct pci_dev *pdev)
1801 : {
1802 : u32 value[256 / 4];
1803 : int i;
1804 :
1805 0 : pci_info(pdev, "config space:\n");
1806 :
1807 0 : for (i = 0; i < 256; i += 4)
1808 0 : pci_read_config_dword(pdev, i, &value[i / 4]);
1809 :
1810 0 : print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 1,
1811 : value, 256, false);
1812 0 : }
1813 :
1814 : /**
1815 : * pci_setup_device - Fill in class and map information of a device
1816 : * @dev: the device structure to fill
1817 : *
1818 : * Initialize the device structure with information about the device's
1819 : * vendor,class,memory and IO-space addresses, IRQ lines etc.
1820 : * Called at initialisation of the PCI subsystem and by CardBus services.
1821 : * Returns 0 on success and negative if unknown type of device (not normal,
1822 : * bridge or CardBus).
1823 : */
1824 0 : int pci_setup_device(struct pci_dev *dev)
1825 : {
1826 : u32 class;
1827 : u16 cmd;
1828 : u8 hdr_type;
1829 0 : int pos = 0;
1830 : struct pci_bus_region region;
1831 : struct resource *res;
1832 :
1833 0 : hdr_type = pci_hdr_type(dev);
1834 :
1835 0 : dev->sysdata = dev->bus->sysdata;
1836 0 : dev->dev.parent = dev->bus->bridge;
1837 0 : dev->dev.bus = &pci_bus_type;
1838 0 : dev->hdr_type = hdr_type & 0x7f;
1839 0 : dev->multifunction = !!(hdr_type & 0x80);
1840 0 : dev->error_state = pci_channel_io_normal;
1841 0 : set_pcie_port_type(dev);
1842 :
1843 0 : pci_set_of_node(dev);
1844 0 : pci_set_acpi_fwnode(dev);
1845 0 : if (dev->dev.fwnode && !fwnode_device_is_available(dev->dev.fwnode))
1846 : return -ENODEV;
1847 :
1848 0 : pci_dev_assign_slot(dev);
1849 :
1850 : /*
1851 : * Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
1852 : * set this higher, assuming the system even supports it.
1853 : */
1854 0 : dev->dma_mask = 0xffffffff;
1855 :
1856 0 : dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
1857 0 : dev->bus->number, PCI_SLOT(dev->devfn),
1858 0 : PCI_FUNC(dev->devfn));
1859 :
1860 0 : class = pci_class(dev);
1861 :
1862 0 : dev->revision = class & 0xff;
1863 0 : dev->class = class >> 8; /* upper 3 bytes */
1864 :
1865 0 : if (pci_early_dump)
1866 0 : early_dump_pci_device(dev);
1867 :
1868 : /* Need to have dev->class ready */
1869 0 : dev->cfg_size = pci_cfg_space_size(dev);
1870 :
1871 : /* Need to have dev->cfg_size ready */
1872 0 : set_pcie_thunderbolt(dev);
1873 :
1874 0 : set_pcie_untrusted(dev);
1875 :
1876 : /* "Unknown power state" */
1877 0 : dev->current_state = PCI_UNKNOWN;
1878 :
1879 : /* Early fixups, before probing the BARs */
1880 0 : pci_fixup_device(pci_fixup_early, dev);
1881 :
1882 0 : pci_set_removable(dev);
1883 :
1884 0 : pci_info(dev, "[%04x:%04x] type %02x class %#08x\n",
1885 : dev->vendor, dev->device, dev->hdr_type, dev->class);
1886 :
1887 : /* Device class may be changed after fixup */
1888 0 : class = dev->class >> 8;
1889 :
1890 0 : if (dev->non_compliant_bars && !dev->mmio_always_on) {
1891 0 : pci_read_config_word(dev, PCI_COMMAND, &cmd);
1892 0 : if (cmd & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) {
1893 0 : pci_info(dev, "device has non-compliant BARs; disabling IO/MEM decoding\n");
1894 0 : cmd &= ~PCI_COMMAND_IO;
1895 0 : cmd &= ~PCI_COMMAND_MEMORY;
1896 0 : pci_write_config_word(dev, PCI_COMMAND, cmd);
1897 : }
1898 : }
1899 :
1900 0 : dev->broken_intx_masking = pci_intx_mask_broken(dev);
1901 :
1902 0 : switch (dev->hdr_type) { /* header type */
1903 : case PCI_HEADER_TYPE_NORMAL: /* standard header */
1904 0 : if (class == PCI_CLASS_BRIDGE_PCI)
1905 : goto bad;
1906 0 : pci_read_irq(dev);
1907 0 : pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1908 :
1909 0 : pci_subsystem_ids(dev, &dev->subsystem_vendor, &dev->subsystem_device);
1910 :
1911 : /*
1912 : * Do the ugly legacy mode stuff here rather than broken chip
1913 : * quirk code. Legacy mode ATA controllers have fixed
1914 : * addresses. These are not always echoed in BAR0-3, and
1915 : * BAR0-3 in a few cases contain junk!
1916 : */
1917 0 : if (class == PCI_CLASS_STORAGE_IDE) {
1918 : u8 progif;
1919 0 : pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1920 0 : if ((progif & 1) == 0) {
1921 0 : region.start = 0x1F0;
1922 0 : region.end = 0x1F7;
1923 0 : res = &dev->resource[0];
1924 0 : res->flags = LEGACY_IO_RESOURCE;
1925 0 : pcibios_bus_to_resource(dev->bus, res, ®ion);
1926 0 : pci_info(dev, "legacy IDE quirk: reg 0x10: %pR\n",
1927 : res);
1928 0 : region.start = 0x3F6;
1929 0 : region.end = 0x3F6;
1930 0 : res = &dev->resource[1];
1931 0 : res->flags = LEGACY_IO_RESOURCE;
1932 0 : pcibios_bus_to_resource(dev->bus, res, ®ion);
1933 0 : pci_info(dev, "legacy IDE quirk: reg 0x14: %pR\n",
1934 : res);
1935 : }
1936 0 : if ((progif & 4) == 0) {
1937 0 : region.start = 0x170;
1938 0 : region.end = 0x177;
1939 0 : res = &dev->resource[2];
1940 0 : res->flags = LEGACY_IO_RESOURCE;
1941 0 : pcibios_bus_to_resource(dev->bus, res, ®ion);
1942 0 : pci_info(dev, "legacy IDE quirk: reg 0x18: %pR\n",
1943 : res);
1944 0 : region.start = 0x376;
1945 0 : region.end = 0x376;
1946 0 : res = &dev->resource[3];
1947 0 : res->flags = LEGACY_IO_RESOURCE;
1948 0 : pcibios_bus_to_resource(dev->bus, res, ®ion);
1949 0 : pci_info(dev, "legacy IDE quirk: reg 0x1c: %pR\n",
1950 : res);
1951 : }
1952 : }
1953 : break;
1954 :
1955 : case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
1956 : /*
1957 : * The PCI-to-PCI bridge spec requires that subtractive
1958 : * decoding (i.e. transparent) bridge must have programming
1959 : * interface code of 0x01.
1960 : */
1961 0 : pci_read_irq(dev);
1962 0 : dev->transparent = ((dev->class & 0xff) == 1);
1963 0 : pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1964 0 : pci_read_bridge_windows(dev);
1965 0 : set_pcie_hotplug_bridge(dev);
1966 0 : pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1967 0 : if (pos) {
1968 0 : pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1969 0 : pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1970 : }
1971 : break;
1972 :
1973 : case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
1974 0 : if (class != PCI_CLASS_BRIDGE_CARDBUS)
1975 : goto bad;
1976 0 : pci_read_irq(dev);
1977 0 : pci_read_bases(dev, 1, 0);
1978 0 : pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1979 0 : pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1980 0 : break;
1981 :
1982 : default: /* unknown header */
1983 0 : pci_err(dev, "unknown header type %02x, ignoring device\n",
1984 : dev->hdr_type);
1985 0 : pci_release_of_node(dev);
1986 0 : return -EIO;
1987 :
1988 : bad:
1989 0 : pci_err(dev, "ignoring class %#08x (doesn't match header type %02x)\n",
1990 : dev->class, dev->hdr_type);
1991 0 : dev->class = PCI_CLASS_NOT_DEFINED << 8;
1992 : }
1993 :
1994 : /* We found a fine healthy device, go go go... */
1995 : return 0;
1996 : }
1997 :
1998 0 : static void pci_configure_mps(struct pci_dev *dev)
1999 : {
2000 0 : struct pci_dev *bridge = pci_upstream_bridge(dev);
2001 : int mps, mpss, p_mps, rc;
2002 :
2003 0 : if (!pci_is_pcie(dev))
2004 : return;
2005 :
2006 : /* MPS and MRRS fields are of type 'RsvdP' for VFs, short-circuit out */
2007 0 : if (dev->is_virtfn)
2008 : return;
2009 :
2010 : /*
2011 : * For Root Complex Integrated Endpoints, program the maximum
2012 : * supported value unless limited by the PCIE_BUS_PEER2PEER case.
2013 : */
2014 0 : if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) {
2015 0 : if (pcie_bus_config == PCIE_BUS_PEER2PEER)
2016 : mps = 128;
2017 : else
2018 0 : mps = 128 << dev->pcie_mpss;
2019 0 : rc = pcie_set_mps(dev, mps);
2020 0 : if (rc) {
2021 0 : pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
2022 : mps);
2023 : }
2024 : return;
2025 : }
2026 :
2027 0 : if (!bridge || !pci_is_pcie(bridge))
2028 : return;
2029 :
2030 0 : mps = pcie_get_mps(dev);
2031 0 : p_mps = pcie_get_mps(bridge);
2032 :
2033 0 : if (mps == p_mps)
2034 : return;
2035 :
2036 0 : if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
2037 0 : 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",
2038 : mps, pci_name(bridge), p_mps);
2039 0 : return;
2040 : }
2041 :
2042 : /*
2043 : * Fancier MPS configuration is done later by
2044 : * pcie_bus_configure_settings()
2045 : */
2046 0 : if (pcie_bus_config != PCIE_BUS_DEFAULT)
2047 : return;
2048 :
2049 0 : mpss = 128 << dev->pcie_mpss;
2050 0 : if (mpss < p_mps && pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT) {
2051 0 : pcie_set_mps(bridge, mpss);
2052 0 : pci_info(dev, "Upstream bridge's Max Payload Size set to %d (was %d, max %d)\n",
2053 : mpss, p_mps, 128 << bridge->pcie_mpss);
2054 0 : p_mps = pcie_get_mps(bridge);
2055 : }
2056 :
2057 0 : rc = pcie_set_mps(dev, p_mps);
2058 0 : if (rc) {
2059 0 : pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
2060 : p_mps);
2061 0 : return;
2062 : }
2063 :
2064 0 : pci_info(dev, "Max Payload Size set to %d (was %d, max %d)\n",
2065 : p_mps, mps, mpss);
2066 : }
2067 :
2068 0 : int pci_configure_extended_tags(struct pci_dev *dev, void *ign)
2069 : {
2070 : struct pci_host_bridge *host;
2071 : u32 cap;
2072 : u16 ctl;
2073 : int ret;
2074 :
2075 0 : if (!pci_is_pcie(dev))
2076 : return 0;
2077 :
2078 0 : ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap);
2079 0 : if (ret)
2080 : return 0;
2081 :
2082 0 : if (!(cap & PCI_EXP_DEVCAP_EXT_TAG))
2083 : return 0;
2084 :
2085 0 : ret = pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl);
2086 0 : if (ret)
2087 : return 0;
2088 :
2089 0 : host = pci_find_host_bridge(dev->bus);
2090 0 : if (!host)
2091 : return 0;
2092 :
2093 : /*
2094 : * If some device in the hierarchy doesn't handle Extended Tags
2095 : * correctly, make sure they're disabled.
2096 : */
2097 0 : if (host->no_ext_tags) {
2098 0 : if (ctl & PCI_EXP_DEVCTL_EXT_TAG) {
2099 0 : pci_info(dev, "disabling Extended Tags\n");
2100 : pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
2101 : PCI_EXP_DEVCTL_EXT_TAG);
2102 : }
2103 : return 0;
2104 : }
2105 :
2106 0 : if (!(ctl & PCI_EXP_DEVCTL_EXT_TAG)) {
2107 0 : pci_info(dev, "enabling Extended Tags\n");
2108 : pcie_capability_set_word(dev, PCI_EXP_DEVCTL,
2109 : PCI_EXP_DEVCTL_EXT_TAG);
2110 : }
2111 : return 0;
2112 : }
2113 :
2114 : /**
2115 : * pcie_relaxed_ordering_enabled - Probe for PCIe relaxed ordering enable
2116 : * @dev: PCI device to query
2117 : *
2118 : * Returns true if the device has enabled relaxed ordering attribute.
2119 : */
2120 0 : bool pcie_relaxed_ordering_enabled(struct pci_dev *dev)
2121 : {
2122 : u16 v;
2123 :
2124 0 : pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &v);
2125 :
2126 0 : return !!(v & PCI_EXP_DEVCTL_RELAX_EN);
2127 : }
2128 : EXPORT_SYMBOL(pcie_relaxed_ordering_enabled);
2129 :
2130 0 : static void pci_configure_relaxed_ordering(struct pci_dev *dev)
2131 : {
2132 : struct pci_dev *root;
2133 :
2134 : /* PCI_EXP_DEVICE_RELAX_EN is RsvdP in VFs */
2135 0 : if (dev->is_virtfn)
2136 : return;
2137 :
2138 0 : if (!pcie_relaxed_ordering_enabled(dev))
2139 : return;
2140 :
2141 : /*
2142 : * For now, we only deal with Relaxed Ordering issues with Root
2143 : * Ports. Peer-to-Peer DMA is another can of worms.
2144 : */
2145 0 : root = pcie_find_root_port(dev);
2146 0 : if (!root)
2147 : return;
2148 :
2149 0 : if (root->dev_flags & PCI_DEV_FLAGS_NO_RELAXED_ORDERING) {
2150 0 : pcie_capability_clear_word(dev, PCI_EXP_DEVCTL,
2151 : PCI_EXP_DEVCTL_RELAX_EN);
2152 0 : pci_info(dev, "Relaxed Ordering disabled because the Root Port didn't support it\n");
2153 : }
2154 : }
2155 :
2156 0 : static void pci_configure_ltr(struct pci_dev *dev)
2157 : {
2158 : #ifdef CONFIG_PCIEASPM
2159 0 : struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
2160 : struct pci_dev *bridge;
2161 : u32 cap, ctl;
2162 :
2163 0 : if (!pci_is_pcie(dev))
2164 0 : return;
2165 :
2166 : /* Read L1 PM substate capabilities */
2167 0 : dev->l1ss = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_L1SS);
2168 :
2169 0 : pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
2170 0 : if (!(cap & PCI_EXP_DEVCAP2_LTR))
2171 : return;
2172 :
2173 0 : pcie_capability_read_dword(dev, PCI_EXP_DEVCTL2, &ctl);
2174 0 : if (ctl & PCI_EXP_DEVCTL2_LTR_EN) {
2175 0 : if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
2176 0 : dev->ltr_path = 1;
2177 0 : return;
2178 : }
2179 :
2180 0 : bridge = pci_upstream_bridge(dev);
2181 0 : if (bridge && bridge->ltr_path)
2182 0 : dev->ltr_path = 1;
2183 :
2184 : return;
2185 : }
2186 :
2187 0 : if (!host->native_ltr)
2188 : return;
2189 :
2190 : /*
2191 : * Software must not enable LTR in an Endpoint unless the Root
2192 : * Complex and all intermediate Switches indicate support for LTR.
2193 : * PCIe r4.0, sec 6.18.
2194 : */
2195 0 : if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
2196 0 : pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
2197 : PCI_EXP_DEVCTL2_LTR_EN);
2198 0 : dev->ltr_path = 1;
2199 0 : return;
2200 : }
2201 :
2202 : /*
2203 : * If we're configuring a hot-added device, LTR was likely
2204 : * disabled in the upstream bridge, so re-enable it before enabling
2205 : * it in the new device.
2206 : */
2207 0 : bridge = pci_upstream_bridge(dev);
2208 0 : if (bridge && bridge->ltr_path) {
2209 0 : pci_bridge_reconfigure_ltr(dev);
2210 0 : pcie_capability_set_word(dev, PCI_EXP_DEVCTL2,
2211 : PCI_EXP_DEVCTL2_LTR_EN);
2212 0 : dev->ltr_path = 1;
2213 : }
2214 : #endif
2215 : }
2216 :
2217 : static void pci_configure_eetlp_prefix(struct pci_dev *dev)
2218 : {
2219 : #ifdef CONFIG_PCI_PASID
2220 : struct pci_dev *bridge;
2221 : int pcie_type;
2222 : u32 cap;
2223 :
2224 : if (!pci_is_pcie(dev))
2225 : return;
2226 :
2227 : pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap);
2228 : if (!(cap & PCI_EXP_DEVCAP2_EE_PREFIX))
2229 : return;
2230 :
2231 : pcie_type = pci_pcie_type(dev);
2232 : if (pcie_type == PCI_EXP_TYPE_ROOT_PORT ||
2233 : pcie_type == PCI_EXP_TYPE_RC_END)
2234 : dev->eetlp_prefix_path = 1;
2235 : else {
2236 : bridge = pci_upstream_bridge(dev);
2237 : if (bridge && bridge->eetlp_prefix_path)
2238 : dev->eetlp_prefix_path = 1;
2239 : }
2240 : #endif
2241 : }
2242 :
2243 0 : static void pci_configure_serr(struct pci_dev *dev)
2244 : {
2245 : u16 control;
2246 :
2247 0 : if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
2248 :
2249 : /*
2250 : * A bridge will not forward ERR_ messages coming from an
2251 : * endpoint unless SERR# forwarding is enabled.
2252 : */
2253 0 : pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &control);
2254 0 : if (!(control & PCI_BRIDGE_CTL_SERR)) {
2255 0 : control |= PCI_BRIDGE_CTL_SERR;
2256 0 : pci_write_config_word(dev, PCI_BRIDGE_CONTROL, control);
2257 : }
2258 : }
2259 0 : }
2260 :
2261 0 : static void pci_configure_device(struct pci_dev *dev)
2262 : {
2263 0 : pci_configure_mps(dev);
2264 0 : pci_configure_extended_tags(dev, NULL);
2265 0 : pci_configure_relaxed_ordering(dev);
2266 0 : pci_configure_ltr(dev);
2267 0 : pci_configure_eetlp_prefix(dev);
2268 0 : pci_configure_serr(dev);
2269 :
2270 0 : pci_acpi_program_hp_params(dev);
2271 0 : }
2272 :
2273 : static void pci_release_capabilities(struct pci_dev *dev)
2274 : {
2275 0 : pci_aer_exit(dev);
2276 0 : pci_rcec_exit(dev);
2277 0 : pci_iov_release(dev);
2278 0 : pci_free_cap_save_buffers(dev);
2279 : }
2280 :
2281 : /**
2282 : * pci_release_dev - Free a PCI device structure when all users of it are
2283 : * finished
2284 : * @dev: device that's been disconnected
2285 : *
2286 : * Will be called only by the device core when all users of this PCI device are
2287 : * done.
2288 : */
2289 0 : static void pci_release_dev(struct device *dev)
2290 : {
2291 : struct pci_dev *pci_dev;
2292 :
2293 0 : pci_dev = to_pci_dev(dev);
2294 0 : pci_release_capabilities(pci_dev);
2295 0 : pci_release_of_node(pci_dev);
2296 0 : pcibios_release_device(pci_dev);
2297 0 : pci_bus_put(pci_dev->bus);
2298 0 : kfree(pci_dev->driver_override);
2299 0 : bitmap_free(pci_dev->dma_alias_mask);
2300 : dev_dbg(dev, "device released\n");
2301 0 : kfree(pci_dev);
2302 0 : }
2303 :
2304 0 : struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
2305 : {
2306 : struct pci_dev *dev;
2307 :
2308 0 : dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
2309 0 : if (!dev)
2310 : return NULL;
2311 :
2312 0 : INIT_LIST_HEAD(&dev->bus_list);
2313 0 : dev->dev.type = &pci_dev_type;
2314 0 : dev->bus = pci_bus_get(bus);
2315 0 : dev->driver_exclusive_resource = (struct resource) {
2316 : .name = "PCI Exclusive",
2317 : .start = 0,
2318 : .end = -1,
2319 : };
2320 :
2321 : #ifdef CONFIG_PCI_MSI
2322 : raw_spin_lock_init(&dev->msi_lock);
2323 : #endif
2324 0 : return dev;
2325 : }
2326 : EXPORT_SYMBOL(pci_alloc_dev);
2327 :
2328 : static bool pci_bus_crs_vendor_id(u32 l)
2329 : {
2330 0 : return (l & 0xffff) == PCI_VENDOR_ID_PCI_SIG;
2331 : }
2332 :
2333 0 : static bool pci_bus_wait_crs(struct pci_bus *bus, int devfn, u32 *l,
2334 : int timeout)
2335 : {
2336 0 : int delay = 1;
2337 :
2338 0 : if (!pci_bus_crs_vendor_id(*l))
2339 : return true; /* not a CRS completion */
2340 :
2341 0 : if (!timeout)
2342 : return false; /* CRS, but caller doesn't want to wait */
2343 :
2344 : /*
2345 : * We got the reserved Vendor ID that indicates a completion with
2346 : * Configuration Request Retry Status (CRS). Retry until we get a
2347 : * valid Vendor ID or we time out.
2348 : */
2349 0 : while (pci_bus_crs_vendor_id(*l)) {
2350 0 : if (delay > timeout) {
2351 0 : pr_warn("pci %04x:%02x:%02x.%d: not ready after %dms; giving up\n",
2352 : pci_domain_nr(bus), bus->number,
2353 : PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2354 :
2355 0 : return false;
2356 : }
2357 0 : if (delay >= 1000)
2358 0 : pr_info("pci %04x:%02x:%02x.%d: not ready after %dms; waiting\n",
2359 : pci_domain_nr(bus), bus->number,
2360 : PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2361 :
2362 0 : msleep(delay);
2363 0 : delay *= 2;
2364 :
2365 0 : if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
2366 : return false;
2367 : }
2368 :
2369 0 : if (delay >= 1000)
2370 0 : pr_info("pci %04x:%02x:%02x.%d: ready after %dms\n",
2371 : pci_domain_nr(bus), bus->number,
2372 : PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1);
2373 :
2374 : return true;
2375 : }
2376 :
2377 0 : bool pci_bus_generic_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
2378 : int timeout)
2379 : {
2380 0 : if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
2381 : return false;
2382 :
2383 : /* Some broken boards return 0 or ~0 (PCI_ERROR_RESPONSE) if a slot is empty: */
2384 0 : if (PCI_POSSIBLE_ERROR(*l) || *l == 0x00000000 ||
2385 0 : *l == 0x0000ffff || *l == 0xffff0000)
2386 : return false;
2387 :
2388 0 : if (pci_bus_crs_vendor_id(*l))
2389 0 : return pci_bus_wait_crs(bus, devfn, l, timeout);
2390 :
2391 : return true;
2392 : }
2393 :
2394 0 : bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
2395 : int timeout)
2396 : {
2397 : #ifdef CONFIG_PCI_QUIRKS
2398 0 : struct pci_dev *bridge = bus->self;
2399 :
2400 : /*
2401 : * Certain IDT switches have an issue where they improperly trigger
2402 : * ACS Source Validation errors on completions for config reads.
2403 : */
2404 0 : if (bridge && bridge->vendor == PCI_VENDOR_ID_IDT &&
2405 : bridge->device == 0x80b5)
2406 0 : return pci_idt_bus_quirk(bus, devfn, l, timeout);
2407 : #endif
2408 :
2409 0 : return pci_bus_generic_read_dev_vendor_id(bus, devfn, l, timeout);
2410 : }
2411 : EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
2412 :
2413 : /*
2414 : * Read the config data for a PCI device, sanity-check it,
2415 : * and fill in the dev structure.
2416 : */
2417 0 : static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
2418 : {
2419 : struct pci_dev *dev;
2420 : u32 l;
2421 :
2422 0 : if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
2423 : return NULL;
2424 :
2425 0 : dev = pci_alloc_dev(bus);
2426 0 : if (!dev)
2427 : return NULL;
2428 :
2429 0 : dev->devfn = devfn;
2430 0 : dev->vendor = l & 0xffff;
2431 0 : dev->device = (l >> 16) & 0xffff;
2432 :
2433 0 : if (pci_setup_device(dev)) {
2434 0 : pci_bus_put(dev->bus);
2435 0 : kfree(dev);
2436 0 : return NULL;
2437 : }
2438 :
2439 : return dev;
2440 : }
2441 :
2442 0 : void pcie_report_downtraining(struct pci_dev *dev)
2443 : {
2444 0 : if (!pci_is_pcie(dev))
2445 : return;
2446 :
2447 : /* Look from the device up to avoid downstream ports with no devices */
2448 0 : if ((pci_pcie_type(dev) != PCI_EXP_TYPE_ENDPOINT) &&
2449 0 : (pci_pcie_type(dev) != PCI_EXP_TYPE_LEG_END) &&
2450 0 : (pci_pcie_type(dev) != PCI_EXP_TYPE_UPSTREAM))
2451 : return;
2452 :
2453 : /* Multi-function PCIe devices share the same link/status */
2454 0 : if (PCI_FUNC(dev->devfn) != 0 || dev->is_virtfn)
2455 : return;
2456 :
2457 : /* Print link status only if the device is constrained by the fabric */
2458 0 : __pcie_print_link_status(dev, false);
2459 : }
2460 :
2461 0 : static void pci_init_capabilities(struct pci_dev *dev)
2462 : {
2463 0 : pci_ea_init(dev); /* Enhanced Allocation */
2464 0 : pci_msi_init(dev); /* Disable MSI */
2465 0 : pci_msix_init(dev); /* Disable MSI-X */
2466 :
2467 : /* Buffers for saving PCIe and PCI-X capabilities */
2468 0 : pci_allocate_cap_save_buffers(dev);
2469 :
2470 0 : pci_pm_init(dev); /* Power Management */
2471 0 : pci_vpd_init(dev); /* Vital Product Data */
2472 0 : pci_configure_ari(dev); /* Alternative Routing-ID Forwarding */
2473 0 : pci_iov_init(dev); /* Single Root I/O Virtualization */
2474 0 : pci_ats_init(dev); /* Address Translation Services */
2475 0 : pci_pri_init(dev); /* Page Request Interface */
2476 0 : pci_pasid_init(dev); /* Process Address Space ID */
2477 0 : pci_acs_init(dev); /* Access Control Services */
2478 0 : pci_ptm_init(dev); /* Precision Time Measurement */
2479 0 : pci_aer_init(dev); /* Advanced Error Reporting */
2480 0 : pci_dpc_init(dev); /* Downstream Port Containment */
2481 0 : pci_rcec_init(dev); /* Root Complex Event Collector */
2482 :
2483 0 : pcie_report_downtraining(dev);
2484 0 : pci_init_reset_methods(dev);
2485 0 : }
2486 :
2487 : /*
2488 : * This is the equivalent of pci_host_bridge_msi_domain() that acts on
2489 : * devices. Firmware interfaces that can select the MSI domain on a
2490 : * per-device basis should be called from here.
2491 : */
2492 : static struct irq_domain *pci_dev_msi_domain(struct pci_dev *dev)
2493 : {
2494 : struct irq_domain *d;
2495 :
2496 : /*
2497 : * If a domain has been set through the pcibios_device_add()
2498 : * callback, then this is the one (platform code knows best).
2499 : */
2500 0 : d = dev_get_msi_domain(&dev->dev);
2501 0 : if (d)
2502 : return d;
2503 :
2504 : /*
2505 : * Let's see if we have a firmware interface able to provide
2506 : * the domain.
2507 : */
2508 0 : d = pci_msi_get_device_domain(dev);
2509 0 : if (d)
2510 : return d;
2511 :
2512 : return NULL;
2513 : }
2514 :
2515 0 : static void pci_set_msi_domain(struct pci_dev *dev)
2516 : {
2517 : struct irq_domain *d;
2518 :
2519 : /*
2520 : * If the platform or firmware interfaces cannot supply a
2521 : * device-specific MSI domain, then inherit the default domain
2522 : * from the host bridge itself.
2523 : */
2524 0 : d = pci_dev_msi_domain(dev);
2525 0 : if (!d)
2526 0 : d = dev_get_msi_domain(&dev->bus->dev);
2527 :
2528 0 : dev_set_msi_domain(&dev->dev, d);
2529 0 : }
2530 :
2531 0 : void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
2532 : {
2533 : int ret;
2534 :
2535 0 : pci_configure_device(dev);
2536 :
2537 0 : device_initialize(&dev->dev);
2538 0 : dev->dev.release = pci_release_dev;
2539 :
2540 0 : set_dev_node(&dev->dev, pcibus_to_node(bus));
2541 0 : dev->dev.dma_mask = &dev->dma_mask;
2542 0 : dev->dev.dma_parms = &dev->dma_parms;
2543 0 : dev->dev.coherent_dma_mask = 0xffffffffull;
2544 :
2545 0 : dma_set_max_seg_size(&dev->dev, 65536);
2546 0 : dma_set_seg_boundary(&dev->dev, 0xffffffff);
2547 :
2548 : /* Fix up broken headers */
2549 0 : pci_fixup_device(pci_fixup_header, dev);
2550 :
2551 0 : pci_reassigndev_resource_alignment(dev);
2552 :
2553 0 : dev->state_saved = false;
2554 :
2555 0 : pci_init_capabilities(dev);
2556 :
2557 : /*
2558 : * Add the device to our list of discovered devices
2559 : * and the bus list for fixup functions, etc.
2560 : */
2561 0 : down_write(&pci_bus_sem);
2562 0 : list_add_tail(&dev->bus_list, &bus->devices);
2563 0 : up_write(&pci_bus_sem);
2564 :
2565 0 : ret = pcibios_device_add(dev);
2566 0 : WARN_ON(ret < 0);
2567 :
2568 : /* Set up MSI IRQ domain */
2569 0 : pci_set_msi_domain(dev);
2570 :
2571 : /* Notifier could use PCI capabilities */
2572 0 : dev->match_driver = false;
2573 0 : ret = device_add(&dev->dev);
2574 0 : WARN_ON(ret < 0);
2575 0 : }
2576 :
2577 0 : struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn)
2578 : {
2579 : struct pci_dev *dev;
2580 :
2581 0 : dev = pci_get_slot(bus, devfn);
2582 0 : if (dev) {
2583 0 : pci_dev_put(dev);
2584 0 : return dev;
2585 : }
2586 :
2587 0 : dev = pci_scan_device(bus, devfn);
2588 0 : if (!dev)
2589 : return NULL;
2590 :
2591 0 : pci_device_add(dev, bus);
2592 :
2593 0 : return dev;
2594 : }
2595 : EXPORT_SYMBOL(pci_scan_single_device);
2596 :
2597 0 : static int next_ari_fn(struct pci_bus *bus, struct pci_dev *dev, int fn)
2598 : {
2599 : int pos;
2600 0 : u16 cap = 0;
2601 : unsigned int next_fn;
2602 :
2603 0 : if (!dev)
2604 : return -ENODEV;
2605 :
2606 0 : pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
2607 0 : if (!pos)
2608 : return -ENODEV;
2609 :
2610 0 : pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap);
2611 0 : next_fn = PCI_ARI_CAP_NFN(cap);
2612 0 : if (next_fn <= fn)
2613 : return -ENODEV; /* protect against malformed list */
2614 :
2615 0 : return next_fn;
2616 : }
2617 :
2618 0 : static int next_fn(struct pci_bus *bus, struct pci_dev *dev, int fn)
2619 : {
2620 0 : if (pci_ari_enabled(bus))
2621 0 : return next_ari_fn(bus, dev, fn);
2622 :
2623 0 : if (fn >= 7)
2624 : return -ENODEV;
2625 : /* only multifunction devices may have more functions */
2626 0 : if (dev && !dev->multifunction)
2627 : return -ENODEV;
2628 :
2629 0 : return fn + 1;
2630 : }
2631 :
2632 0 : static int only_one_child(struct pci_bus *bus)
2633 : {
2634 0 : struct pci_dev *bridge = bus->self;
2635 :
2636 : /*
2637 : * Systems with unusual topologies set PCI_SCAN_ALL_PCIE_DEVS so
2638 : * we scan for all possible devices, not just Device 0.
2639 : */
2640 0 : if (pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
2641 : return 0;
2642 :
2643 : /*
2644 : * A PCIe Downstream Port normally leads to a Link with only Device
2645 : * 0 on it (PCIe spec r3.1, sec 7.3.1). As an optimization, scan
2646 : * only for Device 0 in that situation.
2647 : */
2648 0 : if (bridge && pci_is_pcie(bridge) && pcie_downstream_port(bridge))
2649 : return 1;
2650 :
2651 : return 0;
2652 : }
2653 :
2654 : /**
2655 : * pci_scan_slot - Scan a PCI slot on a bus for devices
2656 : * @bus: PCI bus to scan
2657 : * @devfn: slot number to scan (must have zero function)
2658 : *
2659 : * Scan a PCI slot on the specified PCI bus for devices, adding
2660 : * discovered devices to the @bus->devices list. New devices
2661 : * will not have is_added set.
2662 : *
2663 : * Returns the number of new devices found.
2664 : */
2665 0 : int pci_scan_slot(struct pci_bus *bus, int devfn)
2666 : {
2667 : struct pci_dev *dev;
2668 0 : int fn = 0, nr = 0;
2669 :
2670 0 : if (only_one_child(bus) && (devfn > 0))
2671 : return 0; /* Already scanned the entire slot */
2672 :
2673 : do {
2674 0 : dev = pci_scan_single_device(bus, devfn + fn);
2675 0 : if (dev) {
2676 0 : if (!pci_dev_is_added(dev))
2677 0 : nr++;
2678 0 : if (fn > 0)
2679 0 : dev->multifunction = 1;
2680 0 : } else if (fn == 0) {
2681 : /*
2682 : * Function 0 is required unless we are running on
2683 : * a hypervisor that passes through individual PCI
2684 : * functions.
2685 : */
2686 : if (!hypervisor_isolated_pci_functions())
2687 : break;
2688 : }
2689 0 : fn = next_fn(bus, dev, fn);
2690 0 : } while (fn >= 0);
2691 :
2692 : /* Only one slot has PCIe device */
2693 0 : if (bus->self && nr)
2694 0 : pcie_aspm_init_link_state(bus->self);
2695 :
2696 : return nr;
2697 : }
2698 : EXPORT_SYMBOL(pci_scan_slot);
2699 :
2700 0 : static int pcie_find_smpss(struct pci_dev *dev, void *data)
2701 : {
2702 0 : u8 *smpss = data;
2703 :
2704 0 : if (!pci_is_pcie(dev))
2705 : return 0;
2706 :
2707 : /*
2708 : * We don't have a way to change MPS settings on devices that have
2709 : * drivers attached. A hot-added device might support only the minimum
2710 : * MPS setting (MPS=128). Therefore, if the fabric contains a bridge
2711 : * where devices may be hot-added, we limit the fabric MPS to 128 so
2712 : * hot-added devices will work correctly.
2713 : *
2714 : * However, if we hot-add a device to a slot directly below a Root
2715 : * Port, it's impossible for there to be other existing devices below
2716 : * the port. We don't limit the MPS in this case because we can
2717 : * reconfigure MPS on both the Root Port and the hot-added device,
2718 : * and there are no other devices involved.
2719 : *
2720 : * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
2721 : */
2722 0 : if (dev->is_hotplug_bridge &&
2723 0 : pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
2724 0 : *smpss = 0;
2725 :
2726 0 : if (*smpss > dev->pcie_mpss)
2727 0 : *smpss = dev->pcie_mpss;
2728 :
2729 : return 0;
2730 : }
2731 :
2732 0 : static void pcie_write_mps(struct pci_dev *dev, int mps)
2733 : {
2734 : int rc;
2735 :
2736 0 : if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
2737 0 : mps = 128 << dev->pcie_mpss;
2738 :
2739 0 : if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
2740 0 : dev->bus->self)
2741 :
2742 : /*
2743 : * For "Performance", the assumption is made that
2744 : * downstream communication will never be larger than
2745 : * the MRRS. So, the MPS only needs to be configured
2746 : * for the upstream communication. This being the case,
2747 : * walk from the top down and set the MPS of the child
2748 : * to that of the parent bus.
2749 : *
2750 : * Configure the device MPS with the smaller of the
2751 : * device MPSS or the bridge MPS (which is assumed to be
2752 : * properly configured at this point to the largest
2753 : * allowable MPS based on its parent bus).
2754 : */
2755 0 : mps = min(mps, pcie_get_mps(dev->bus->self));
2756 : }
2757 :
2758 0 : rc = pcie_set_mps(dev, mps);
2759 0 : if (rc)
2760 0 : pci_err(dev, "Failed attempting to set the MPS\n");
2761 0 : }
2762 :
2763 0 : static void pcie_write_mrrs(struct pci_dev *dev)
2764 : {
2765 : int rc, mrrs;
2766 :
2767 : /*
2768 : * In the "safe" case, do not configure the MRRS. There appear to be
2769 : * issues with setting MRRS to 0 on a number of devices.
2770 : */
2771 0 : if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
2772 : return;
2773 :
2774 : /*
2775 : * For max performance, the MRRS must be set to the largest supported
2776 : * value. However, it cannot be configured larger than the MPS the
2777 : * device or the bus can support. This should already be properly
2778 : * configured by a prior call to pcie_write_mps().
2779 : */
2780 0 : mrrs = pcie_get_mps(dev);
2781 :
2782 : /*
2783 : * MRRS is a R/W register. Invalid values can be written, but a
2784 : * subsequent read will verify if the value is acceptable or not.
2785 : * If the MRRS value provided is not acceptable (e.g., too large),
2786 : * shrink the value until it is acceptable to the HW.
2787 : */
2788 0 : while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
2789 0 : rc = pcie_set_readrq(dev, mrrs);
2790 0 : if (!rc)
2791 : break;
2792 :
2793 0 : pci_warn(dev, "Failed attempting to set the MRRS\n");
2794 0 : mrrs /= 2;
2795 : }
2796 :
2797 0 : if (mrrs < 128)
2798 0 : 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");
2799 : }
2800 :
2801 0 : static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
2802 : {
2803 : int mps, orig_mps;
2804 :
2805 0 : if (!pci_is_pcie(dev))
2806 : return 0;
2807 :
2808 0 : if (pcie_bus_config == PCIE_BUS_TUNE_OFF ||
2809 : pcie_bus_config == PCIE_BUS_DEFAULT)
2810 : return 0;
2811 :
2812 0 : mps = 128 << *(u8 *)data;
2813 0 : orig_mps = pcie_get_mps(dev);
2814 :
2815 0 : pcie_write_mps(dev, mps);
2816 0 : pcie_write_mrrs(dev);
2817 :
2818 0 : pci_info(dev, "Max Payload Size set to %4d/%4d (was %4d), Max Read Rq %4d\n",
2819 : pcie_get_mps(dev), 128 << dev->pcie_mpss,
2820 : orig_mps, pcie_get_readrq(dev));
2821 :
2822 0 : return 0;
2823 : }
2824 :
2825 : /*
2826 : * pcie_bus_configure_settings() requires that pci_walk_bus work in a top-down,
2827 : * parents then children fashion. If this changes, then this code will not
2828 : * work as designed.
2829 : */
2830 0 : void pcie_bus_configure_settings(struct pci_bus *bus)
2831 : {
2832 0 : u8 smpss = 0;
2833 :
2834 0 : if (!bus->self)
2835 0 : return;
2836 :
2837 0 : if (!pci_is_pcie(bus->self))
2838 : return;
2839 :
2840 : /*
2841 : * FIXME - Peer to peer DMA is possible, though the endpoint would need
2842 : * to be aware of the MPS of the destination. To work around this,
2843 : * simply force the MPS of the entire system to the smallest possible.
2844 : */
2845 0 : if (pcie_bus_config == PCIE_BUS_PEER2PEER)
2846 : smpss = 0;
2847 :
2848 0 : if (pcie_bus_config == PCIE_BUS_SAFE) {
2849 0 : smpss = bus->self->pcie_mpss;
2850 :
2851 0 : pcie_find_smpss(bus->self, &smpss);
2852 0 : pci_walk_bus(bus, pcie_find_smpss, &smpss);
2853 : }
2854 :
2855 0 : pcie_bus_configure_set(bus->self, &smpss);
2856 0 : pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
2857 : }
2858 : EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
2859 :
2860 : /*
2861 : * Called after each bus is probed, but before its children are examined. This
2862 : * is marked as __weak because multiple architectures define it.
2863 : */
2864 0 : void __weak pcibios_fixup_bus(struct pci_bus *bus)
2865 : {
2866 : /* nothing to do, expected to be removed in the future */
2867 0 : }
2868 :
2869 : /**
2870 : * pci_scan_child_bus_extend() - Scan devices below a bus
2871 : * @bus: Bus to scan for devices
2872 : * @available_buses: Total number of buses available (%0 does not try to
2873 : * extend beyond the minimal)
2874 : *
2875 : * Scans devices below @bus including subordinate buses. Returns new
2876 : * subordinate number including all the found devices. Passing
2877 : * @available_buses causes the remaining bus space to be distributed
2878 : * equally between hotplug-capable bridges to allow future extension of the
2879 : * hierarchy.
2880 : */
2881 0 : static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus,
2882 : unsigned int available_buses)
2883 : {
2884 0 : unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0;
2885 0 : unsigned int start = bus->busn_res.start;
2886 0 : unsigned int devfn, cmax, max = start;
2887 : struct pci_dev *dev;
2888 :
2889 : dev_dbg(&bus->dev, "scanning bus\n");
2890 :
2891 : /* Go find them, Rover! */
2892 0 : for (devfn = 0; devfn < 256; devfn += 8)
2893 0 : pci_scan_slot(bus, devfn);
2894 :
2895 : /* Reserve buses for SR-IOV capability */
2896 0 : used_buses = pci_iov_bus_range(bus);
2897 0 : max += used_buses;
2898 :
2899 : /*
2900 : * After performing arch-dependent fixup of the bus, look behind
2901 : * all PCI-to-PCI bridges on this bus.
2902 : */
2903 0 : if (!bus->is_added) {
2904 : dev_dbg(&bus->dev, "fixups for bus\n");
2905 0 : pcibios_fixup_bus(bus);
2906 0 : bus->is_added = 1;
2907 : }
2908 :
2909 : /*
2910 : * Calculate how many hotplug bridges and normal bridges there
2911 : * are on this bus. We will distribute the additional available
2912 : * buses between hotplug bridges.
2913 : */
2914 0 : for_each_pci_bridge(dev, bus) {
2915 0 : if (dev->is_hotplug_bridge)
2916 0 : hotplug_bridges++;
2917 : else
2918 0 : normal_bridges++;
2919 : }
2920 :
2921 : /*
2922 : * Scan bridges that are already configured. We don't touch them
2923 : * unless they are misconfigured (which will be done in the second
2924 : * scan below).
2925 : */
2926 0 : for_each_pci_bridge(dev, bus) {
2927 0 : cmax = max;
2928 0 : max = pci_scan_bridge_extend(bus, dev, max, 0, 0);
2929 :
2930 : /*
2931 : * Reserve one bus for each bridge now to avoid extending
2932 : * hotplug bridges too much during the second scan below.
2933 : */
2934 0 : used_buses++;
2935 0 : if (max - cmax > 1)
2936 0 : used_buses += max - cmax - 1;
2937 : }
2938 :
2939 : /* Scan bridges that need to be reconfigured */
2940 0 : for_each_pci_bridge(dev, bus) {
2941 0 : unsigned int buses = 0;
2942 :
2943 0 : if (!hotplug_bridges && normal_bridges == 1) {
2944 : /*
2945 : * There is only one bridge on the bus (upstream
2946 : * port) so it gets all available buses which it
2947 : * can then distribute to the possible hotplug
2948 : * bridges below.
2949 : */
2950 : buses = available_buses;
2951 0 : } else if (dev->is_hotplug_bridge) {
2952 : /*
2953 : * Distribute the extra buses between hotplug
2954 : * bridges if any.
2955 : */
2956 0 : buses = available_buses / hotplug_bridges;
2957 0 : buses = min(buses, available_buses - used_buses + 1);
2958 : }
2959 :
2960 0 : cmax = max;
2961 0 : max = pci_scan_bridge_extend(bus, dev, cmax, buses, 1);
2962 : /* One bus is already accounted so don't add it again */
2963 0 : if (max - cmax > 1)
2964 0 : used_buses += max - cmax - 1;
2965 : }
2966 :
2967 : /*
2968 : * Make sure a hotplug bridge has at least the minimum requested
2969 : * number of buses but allow it to grow up to the maximum available
2970 : * bus number if there is room.
2971 : */
2972 0 : if (bus->self && bus->self->is_hotplug_bridge) {
2973 0 : used_buses = max_t(unsigned int, available_buses,
2974 : pci_hotplug_bus_size - 1);
2975 0 : if (max - start < used_buses) {
2976 0 : max = start + used_buses;
2977 :
2978 : /* Do not allocate more buses than we have room left */
2979 0 : if (max > bus->busn_res.end)
2980 0 : max = bus->busn_res.end;
2981 :
2982 : dev_dbg(&bus->dev, "%pR extended by %#02x\n",
2983 : &bus->busn_res, max - start);
2984 : }
2985 : }
2986 :
2987 : /*
2988 : * We've scanned the bus and so we know all about what's on
2989 : * the other side of any bridges that may be on this bus plus
2990 : * any devices.
2991 : *
2992 : * Return how far we've got finding sub-buses.
2993 : */
2994 : dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
2995 0 : return max;
2996 : }
2997 :
2998 : /**
2999 : * pci_scan_child_bus() - Scan devices below a bus
3000 : * @bus: Bus to scan for devices
3001 : *
3002 : * Scans devices below @bus including subordinate buses. Returns new
3003 : * subordinate number including all the found devices.
3004 : */
3005 0 : unsigned int pci_scan_child_bus(struct pci_bus *bus)
3006 : {
3007 0 : return pci_scan_child_bus_extend(bus, 0);
3008 : }
3009 : EXPORT_SYMBOL_GPL(pci_scan_child_bus);
3010 :
3011 : /**
3012 : * pcibios_root_bridge_prepare - Platform-specific host bridge setup
3013 : * @bridge: Host bridge to set up
3014 : *
3015 : * Default empty implementation. Replace with an architecture-specific setup
3016 : * routine, if necessary.
3017 : */
3018 0 : int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
3019 : {
3020 0 : return 0;
3021 : }
3022 :
3023 0 : void __weak pcibios_add_bus(struct pci_bus *bus)
3024 : {
3025 0 : }
3026 :
3027 0 : void __weak pcibios_remove_bus(struct pci_bus *bus)
3028 : {
3029 0 : }
3030 :
3031 0 : struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
3032 : struct pci_ops *ops, void *sysdata, struct list_head *resources)
3033 : {
3034 : int error;
3035 : struct pci_host_bridge *bridge;
3036 :
3037 0 : bridge = pci_alloc_host_bridge(0);
3038 0 : if (!bridge)
3039 : return NULL;
3040 :
3041 0 : bridge->dev.parent = parent;
3042 :
3043 0 : list_splice_init(resources, &bridge->windows);
3044 0 : bridge->sysdata = sysdata;
3045 0 : bridge->busnr = bus;
3046 0 : bridge->ops = ops;
3047 :
3048 0 : error = pci_register_host_bridge(bridge);
3049 0 : if (error < 0)
3050 : goto err_out;
3051 :
3052 0 : return bridge->bus;
3053 :
3054 : err_out:
3055 0 : put_device(&bridge->dev);
3056 0 : return NULL;
3057 : }
3058 : EXPORT_SYMBOL_GPL(pci_create_root_bus);
3059 :
3060 0 : int pci_host_probe(struct pci_host_bridge *bridge)
3061 : {
3062 : struct pci_bus *bus, *child;
3063 : int ret;
3064 :
3065 0 : ret = pci_scan_root_bus_bridge(bridge);
3066 0 : if (ret < 0) {
3067 0 : dev_err(bridge->dev.parent, "Scanning root bridge failed");
3068 0 : return ret;
3069 : }
3070 :
3071 0 : bus = bridge->bus;
3072 :
3073 : /*
3074 : * We insert PCI resources into the iomem_resource and
3075 : * ioport_resource trees in either pci_bus_claim_resources()
3076 : * or pci_bus_assign_resources().
3077 : */
3078 0 : if (pci_has_flag(PCI_PROBE_ONLY)) {
3079 0 : pci_bus_claim_resources(bus);
3080 : } else {
3081 0 : pci_bus_size_bridges(bus);
3082 0 : pci_bus_assign_resources(bus);
3083 :
3084 0 : list_for_each_entry(child, &bus->children, node)
3085 0 : pcie_bus_configure_settings(child);
3086 : }
3087 :
3088 0 : pci_bus_add_devices(bus);
3089 0 : return 0;
3090 : }
3091 : EXPORT_SYMBOL_GPL(pci_host_probe);
3092 :
3093 0 : int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
3094 : {
3095 0 : struct resource *res = &b->busn_res;
3096 : struct resource *parent_res, *conflict;
3097 :
3098 0 : res->start = bus;
3099 0 : res->end = bus_max;
3100 0 : res->flags = IORESOURCE_BUS;
3101 :
3102 0 : if (!pci_is_root_bus(b))
3103 0 : parent_res = &b->parent->busn_res;
3104 : else {
3105 0 : parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
3106 0 : res->flags |= IORESOURCE_PCI_FIXED;
3107 : }
3108 :
3109 0 : conflict = request_resource_conflict(parent_res, res);
3110 :
3111 0 : if (conflict)
3112 0 : dev_info(&b->dev,
3113 : "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
3114 : res, pci_is_root_bus(b) ? "domain " : "",
3115 : parent_res, conflict->name, conflict);
3116 :
3117 0 : return conflict == NULL;
3118 : }
3119 :
3120 0 : int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
3121 : {
3122 0 : struct resource *res = &b->busn_res;
3123 0 : struct resource old_res = *res;
3124 : resource_size_t size;
3125 : int ret;
3126 :
3127 0 : if (res->start > bus_max)
3128 : return -EINVAL;
3129 :
3130 0 : size = bus_max - res->start + 1;
3131 0 : ret = adjust_resource(res, res->start, size);
3132 0 : dev_info(&b->dev, "busn_res: %pR end %s updated to %02x\n",
3133 : &old_res, ret ? "can not be" : "is", bus_max);
3134 :
3135 0 : if (!ret && !res->parent)
3136 0 : pci_bus_insert_busn_res(b, res->start, res->end);
3137 :
3138 : return ret;
3139 : }
3140 :
3141 0 : void pci_bus_release_busn_res(struct pci_bus *b)
3142 : {
3143 0 : struct resource *res = &b->busn_res;
3144 : int ret;
3145 :
3146 0 : if (!res->flags || !res->parent)
3147 : return;
3148 :
3149 0 : ret = release_resource(res);
3150 0 : dev_info(&b->dev, "busn_res: %pR %s released\n",
3151 : res, ret ? "can not be" : "is");
3152 : }
3153 :
3154 0 : int pci_scan_root_bus_bridge(struct pci_host_bridge *bridge)
3155 : {
3156 : struct resource_entry *window;
3157 0 : bool found = false;
3158 : struct pci_bus *b;
3159 : int max, bus, ret;
3160 :
3161 0 : if (!bridge)
3162 : return -EINVAL;
3163 :
3164 0 : resource_list_for_each_entry(window, &bridge->windows)
3165 0 : if (window->res->flags & IORESOURCE_BUS) {
3166 0 : bridge->busnr = window->res->start;
3167 0 : found = true;
3168 0 : break;
3169 : }
3170 :
3171 0 : ret = pci_register_host_bridge(bridge);
3172 0 : if (ret < 0)
3173 : return ret;
3174 :
3175 0 : b = bridge->bus;
3176 0 : bus = bridge->busnr;
3177 :
3178 0 : if (!found) {
3179 0 : dev_info(&b->dev,
3180 : "No busn resource found for root bus, will use [bus %02x-ff]\n",
3181 : bus);
3182 0 : pci_bus_insert_busn_res(b, bus, 255);
3183 : }
3184 :
3185 0 : max = pci_scan_child_bus(b);
3186 :
3187 0 : if (!found)
3188 0 : pci_bus_update_busn_res_end(b, max);
3189 :
3190 : return 0;
3191 : }
3192 : EXPORT_SYMBOL(pci_scan_root_bus_bridge);
3193 :
3194 0 : struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
3195 : struct pci_ops *ops, void *sysdata, struct list_head *resources)
3196 : {
3197 : struct resource_entry *window;
3198 0 : bool found = false;
3199 : struct pci_bus *b;
3200 : int max;
3201 :
3202 0 : resource_list_for_each_entry(window, resources)
3203 0 : if (window->res->flags & IORESOURCE_BUS) {
3204 : found = true;
3205 : break;
3206 : }
3207 :
3208 0 : b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
3209 0 : if (!b)
3210 : return NULL;
3211 :
3212 0 : if (!found) {
3213 0 : dev_info(&b->dev,
3214 : "No busn resource found for root bus, will use [bus %02x-ff]\n",
3215 : bus);
3216 0 : pci_bus_insert_busn_res(b, bus, 255);
3217 : }
3218 :
3219 0 : max = pci_scan_child_bus(b);
3220 :
3221 0 : if (!found)
3222 0 : pci_bus_update_busn_res_end(b, max);
3223 :
3224 : return b;
3225 : }
3226 : EXPORT_SYMBOL(pci_scan_root_bus);
3227 :
3228 0 : struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
3229 : void *sysdata)
3230 : {
3231 0 : LIST_HEAD(resources);
3232 : struct pci_bus *b;
3233 :
3234 0 : pci_add_resource(&resources, &ioport_resource);
3235 0 : pci_add_resource(&resources, &iomem_resource);
3236 0 : pci_add_resource(&resources, &busn_resource);
3237 0 : b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
3238 0 : if (b) {
3239 : pci_scan_child_bus(b);
3240 : } else {
3241 0 : pci_free_resource_list(&resources);
3242 : }
3243 0 : return b;
3244 : }
3245 : EXPORT_SYMBOL(pci_scan_bus);
3246 :
3247 : /**
3248 : * pci_rescan_bus_bridge_resize - Scan a PCI bus for devices
3249 : * @bridge: PCI bridge for the bus to scan
3250 : *
3251 : * Scan a PCI bus and child buses for new devices, add them,
3252 : * and enable them, resizing bridge mmio/io resource if necessary
3253 : * and possible. The caller must ensure the child devices are already
3254 : * removed for resizing to occur.
3255 : *
3256 : * Returns the max number of subordinate bus discovered.
3257 : */
3258 0 : unsigned int pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
3259 : {
3260 : unsigned int max;
3261 0 : struct pci_bus *bus = bridge->subordinate;
3262 :
3263 0 : max = pci_scan_child_bus(bus);
3264 :
3265 0 : pci_assign_unassigned_bridge_resources(bridge);
3266 :
3267 0 : pci_bus_add_devices(bus);
3268 :
3269 0 : return max;
3270 : }
3271 :
3272 : /**
3273 : * pci_rescan_bus - Scan a PCI bus for devices
3274 : * @bus: PCI bus to scan
3275 : *
3276 : * Scan a PCI bus and child buses for new devices, add them,
3277 : * and enable them.
3278 : *
3279 : * Returns the max number of subordinate bus discovered.
3280 : */
3281 0 : unsigned int pci_rescan_bus(struct pci_bus *bus)
3282 : {
3283 : unsigned int max;
3284 :
3285 0 : max = pci_scan_child_bus(bus);
3286 0 : pci_assign_unassigned_bus_resources(bus);
3287 0 : pci_bus_add_devices(bus);
3288 :
3289 0 : return max;
3290 : }
3291 : EXPORT_SYMBOL_GPL(pci_rescan_bus);
3292 :
3293 : /*
3294 : * pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal
3295 : * routines should always be executed under this mutex.
3296 : */
3297 : static DEFINE_MUTEX(pci_rescan_remove_lock);
3298 :
3299 0 : void pci_lock_rescan_remove(void)
3300 : {
3301 0 : mutex_lock(&pci_rescan_remove_lock);
3302 0 : }
3303 : EXPORT_SYMBOL_GPL(pci_lock_rescan_remove);
3304 :
3305 0 : void pci_unlock_rescan_remove(void)
3306 : {
3307 0 : mutex_unlock(&pci_rescan_remove_lock);
3308 0 : }
3309 : EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove);
3310 :
3311 0 : static int __init pci_sort_bf_cmp(const struct device *d_a,
3312 : const struct device *d_b)
3313 : {
3314 0 : const struct pci_dev *a = to_pci_dev(d_a);
3315 0 : const struct pci_dev *b = to_pci_dev(d_b);
3316 :
3317 0 : if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
3318 0 : else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
3319 :
3320 0 : if (a->bus->number < b->bus->number) return -1;
3321 0 : else if (a->bus->number > b->bus->number) return 1;
3322 :
3323 0 : if (a->devfn < b->devfn) return -1;
3324 0 : else if (a->devfn > b->devfn) return 1;
3325 :
3326 0 : return 0;
3327 : }
3328 :
3329 0 : void __init pci_sort_breadthfirst(void)
3330 : {
3331 0 : bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);
3332 0 : }
3333 :
3334 0 : int pci_hp_add_bridge(struct pci_dev *dev)
3335 : {
3336 0 : struct pci_bus *parent = dev->bus;
3337 0 : int busnr, start = parent->busn_res.start;
3338 0 : unsigned int available_buses = 0;
3339 0 : int end = parent->busn_res.end;
3340 :
3341 0 : for (busnr = start; busnr <= end; busnr++) {
3342 0 : if (!pci_find_bus(pci_domain_nr(parent), busnr))
3343 : break;
3344 : }
3345 0 : if (busnr-- > end) {
3346 0 : pci_err(dev, "No bus number available for hot-added bridge\n");
3347 0 : return -1;
3348 : }
3349 :
3350 : /* Scan bridges that are already configured */
3351 0 : busnr = pci_scan_bridge(parent, dev, busnr, 0);
3352 :
3353 : /*
3354 : * Distribute the available bus numbers between hotplug-capable
3355 : * bridges to make extending the chain later possible.
3356 : */
3357 0 : available_buses = end - busnr;
3358 :
3359 : /* Scan bridges that need to be reconfigured */
3360 0 : pci_scan_bridge_extend(parent, dev, busnr, available_buses, 1);
3361 :
3362 0 : if (!dev->subordinate)
3363 : return -1;
3364 :
3365 0 : return 0;
3366 : }
3367 : EXPORT_SYMBOL_GPL(pci_hp_add_bridge);
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