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1 /*
2  * probe.c - PCI detection and setup code
3  */
4 
5 #include <linux/kernel.h>
6 #include <linux/delay.h>
7 #include <linux/init.h>
8 #include <linux/pci.h>
9 #include <linux/of_device.h>
10 #include <linux/of_pci.h>
11 #include <linux/pci_hotplug.h>
12 #include <linux/slab.h>
13 #include <linux/module.h>
14 #include <linux/cpumask.h>
15 #include <linux/pci-aspm.h>
16 #include <linux/aer.h>
17 #include <linux/acpi.h>
18 #include <asm-generic/pci-bridge.h>
19 #include "pci.h"
20 
21 #define CARDBUS_LATENCY_TIMER	176	/* secondary latency timer */
22 #define CARDBUS_RESERVE_BUSNR	3
23 
24 static struct resource busn_resource = {
25 	.name	= "PCI busn",
26 	.start	= 0,
27 	.end	= 255,
28 	.flags	= IORESOURCE_BUS,
29 };
30 
31 /* Ugh.  Need to stop exporting this to modules. */
32 LIST_HEAD(pci_root_buses);
33 EXPORT_SYMBOL(pci_root_buses);
34 
35 static LIST_HEAD(pci_domain_busn_res_list);
36 
37 struct pci_domain_busn_res {
38 	struct list_head list;
39 	struct resource res;
40 	int domain_nr;
41 };
42 
get_pci_domain_busn_res(int domain_nr)43 static struct resource *get_pci_domain_busn_res(int domain_nr)
44 {
45 	struct pci_domain_busn_res *r;
46 
47 	list_for_each_entry(r, &pci_domain_busn_res_list, list)
48 		if (r->domain_nr == domain_nr)
49 			return &r->res;
50 
51 	r = kzalloc(sizeof(*r), GFP_KERNEL);
52 	if (!r)
53 		return NULL;
54 
55 	r->domain_nr = domain_nr;
56 	r->res.start = 0;
57 	r->res.end = 0xff;
58 	r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED;
59 
60 	list_add_tail(&r->list, &pci_domain_busn_res_list);
61 
62 	return &r->res;
63 }
64 
find_anything(struct device * dev,void * data)65 static int find_anything(struct device *dev, void *data)
66 {
67 	return 1;
68 }
69 
70 /*
71  * Some device drivers need know if pci is initiated.
72  * Basically, we think pci is not initiated when there
73  * is no device to be found on the pci_bus_type.
74  */
no_pci_devices(void)75 int no_pci_devices(void)
76 {
77 	struct device *dev;
78 	int no_devices;
79 
80 	dev = bus_find_device(&pci_bus_type, NULL, NULL, find_anything);
81 	no_devices = (dev == NULL);
82 	put_device(dev);
83 	return no_devices;
84 }
85 EXPORT_SYMBOL(no_pci_devices);
86 
87 /*
88  * PCI Bus Class
89  */
release_pcibus_dev(struct device * dev)90 static void release_pcibus_dev(struct device *dev)
91 {
92 	struct pci_bus *pci_bus = to_pci_bus(dev);
93 
94 	put_device(pci_bus->bridge);
95 	pci_bus_remove_resources(pci_bus);
96 	pci_release_bus_of_node(pci_bus);
97 	kfree(pci_bus);
98 }
99 
100 static struct class pcibus_class = {
101 	.name		= "pci_bus",
102 	.dev_release	= &release_pcibus_dev,
103 	.dev_groups	= pcibus_groups,
104 };
105 
pcibus_class_init(void)106 static int __init pcibus_class_init(void)
107 {
108 	return class_register(&pcibus_class);
109 }
110 postcore_initcall(pcibus_class_init);
111 
pci_size(u64 base,u64 maxbase,u64 mask)112 static u64 pci_size(u64 base, u64 maxbase, u64 mask)
113 {
114 	u64 size = mask & maxbase;	/* Find the significant bits */
115 	if (!size)
116 		return 0;
117 
118 	/* Get the lowest of them to find the decode size, and
119 	   from that the extent.  */
120 	size = (size & ~(size-1)) - 1;
121 
122 	/* base == maxbase can be valid only if the BAR has
123 	   already been programmed with all 1s.  */
124 	if (base == maxbase && ((base | size) & mask) != mask)
125 		return 0;
126 
127 	return size;
128 }
129 
decode_bar(struct pci_dev * dev,u32 bar)130 static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar)
131 {
132 	u32 mem_type;
133 	unsigned long flags;
134 
135 	if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
136 		flags = bar & ~PCI_BASE_ADDRESS_IO_MASK;
137 		flags |= IORESOURCE_IO;
138 		return flags;
139 	}
140 
141 	flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK;
142 	flags |= IORESOURCE_MEM;
143 	if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
144 		flags |= IORESOURCE_PREFETCH;
145 
146 	mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
147 	switch (mem_type) {
148 	case PCI_BASE_ADDRESS_MEM_TYPE_32:
149 		break;
150 	case PCI_BASE_ADDRESS_MEM_TYPE_1M:
151 		/* 1M mem BAR treated as 32-bit BAR */
152 		break;
153 	case PCI_BASE_ADDRESS_MEM_TYPE_64:
154 		flags |= IORESOURCE_MEM_64;
155 		break;
156 	default:
157 		/* mem unknown type treated as 32-bit BAR */
158 		break;
159 	}
160 	return flags;
161 }
162 
163 #define PCI_COMMAND_DECODE_ENABLE	(PCI_COMMAND_MEMORY | PCI_COMMAND_IO)
164 
165 /**
166  * pci_read_base - read a PCI BAR
167  * @dev: the PCI device
168  * @type: type of the BAR
169  * @res: resource buffer to be filled in
170  * @pos: BAR position in the config space
171  *
172  * Returns 1 if the BAR is 64-bit, or 0 if 32-bit.
173  */
__pci_read_base(struct pci_dev * dev,enum pci_bar_type type,struct resource * res,unsigned int pos)174 int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
175 		    struct resource *res, unsigned int pos)
176 {
177 	u32 l, sz, mask;
178 	u64 l64, sz64, mask64;
179 	u16 orig_cmd;
180 	struct pci_bus_region region, inverted_region;
181 
182 	mask = type ? PCI_ROM_ADDRESS_MASK : ~0;
183 
184 	/* No printks while decoding is disabled! */
185 	if (!dev->mmio_always_on) {
186 		pci_read_config_word(dev, PCI_COMMAND, &orig_cmd);
187 		if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) {
188 			pci_write_config_word(dev, PCI_COMMAND,
189 				orig_cmd & ~PCI_COMMAND_DECODE_ENABLE);
190 		}
191 	}
192 
193 	res->name = pci_name(dev);
194 
195 	pci_read_config_dword(dev, pos, &l);
196 	pci_write_config_dword(dev, pos, l | mask);
197 	pci_read_config_dword(dev, pos, &sz);
198 	pci_write_config_dword(dev, pos, l);
199 
200 	/*
201 	 * All bits set in sz means the device isn't working properly.
202 	 * If the BAR isn't implemented, all bits must be 0.  If it's a
203 	 * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit
204 	 * 1 must be clear.
205 	 */
206 	if (sz == 0xffffffff)
207 		sz = 0;
208 
209 	/*
210 	 * I don't know how l can have all bits set.  Copied from old code.
211 	 * Maybe it fixes a bug on some ancient platform.
212 	 */
213 	if (l == 0xffffffff)
214 		l = 0;
215 
216 	if (type == pci_bar_unknown) {
217 		res->flags = decode_bar(dev, l);
218 		res->flags |= IORESOURCE_SIZEALIGN;
219 		if (res->flags & IORESOURCE_IO) {
220 			l64 = l & PCI_BASE_ADDRESS_IO_MASK;
221 			sz64 = sz & PCI_BASE_ADDRESS_IO_MASK;
222 			mask64 = PCI_BASE_ADDRESS_IO_MASK & (u32)IO_SPACE_LIMIT;
223 		} else {
224 			l64 = l & PCI_BASE_ADDRESS_MEM_MASK;
225 			sz64 = sz & PCI_BASE_ADDRESS_MEM_MASK;
226 			mask64 = (u32)PCI_BASE_ADDRESS_MEM_MASK;
227 		}
228 	} else {
229 		if (l & PCI_ROM_ADDRESS_ENABLE)
230 			res->flags |= IORESOURCE_ROM_ENABLE;
231 		l64 = l & PCI_ROM_ADDRESS_MASK;
232 		sz64 = sz & PCI_ROM_ADDRESS_MASK;
233 		mask64 = PCI_ROM_ADDRESS_MASK;
234 	}
235 
236 	if (res->flags & IORESOURCE_MEM_64) {
237 		pci_read_config_dword(dev, pos + 4, &l);
238 		pci_write_config_dword(dev, pos + 4, ~0);
239 		pci_read_config_dword(dev, pos + 4, &sz);
240 		pci_write_config_dword(dev, pos + 4, l);
241 
242 		l64 |= ((u64)l << 32);
243 		sz64 |= ((u64)sz << 32);
244 		mask64 |= ((u64)~0 << 32);
245 	}
246 
247 	if (!dev->mmio_always_on && (orig_cmd & PCI_COMMAND_DECODE_ENABLE))
248 		pci_write_config_word(dev, PCI_COMMAND, orig_cmd);
249 
250 	if (!sz64)
251 		goto fail;
252 
253 	sz64 = pci_size(l64, sz64, mask64);
254 	if (!sz64) {
255 		dev_info(&dev->dev, FW_BUG "reg 0x%x: invalid BAR (can't size)\n",
256 			 pos);
257 		goto fail;
258 	}
259 
260 	if (res->flags & IORESOURCE_MEM_64) {
261 		if ((sizeof(pci_bus_addr_t) < 8 || sizeof(resource_size_t) < 8)
262 		    && sz64 > 0x100000000ULL) {
263 			res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
264 			res->start = 0;
265 			res->end = 0;
266 			dev_err(&dev->dev, "reg 0x%x: can't handle BAR larger than 4GB (size %#010llx)\n",
267 				pos, (unsigned long long)sz64);
268 			goto out;
269 		}
270 
271 		if ((sizeof(pci_bus_addr_t) < 8) && l) {
272 			/* Above 32-bit boundary; try to reallocate */
273 			res->flags |= IORESOURCE_UNSET;
274 			res->start = 0;
275 			res->end = sz64;
276 			dev_info(&dev->dev, "reg 0x%x: can't handle BAR above 4GB (bus address %#010llx)\n",
277 				 pos, (unsigned long long)l64);
278 			goto out;
279 		}
280 	}
281 
282 	region.start = l64;
283 	region.end = l64 + sz64;
284 
285 	pcibios_bus_to_resource(dev->bus, res, &region);
286 	pcibios_resource_to_bus(dev->bus, &inverted_region, res);
287 
288 	/*
289 	 * If "A" is a BAR value (a bus address), "bus_to_resource(A)" is
290 	 * the corresponding resource address (the physical address used by
291 	 * the CPU.  Converting that resource address back to a bus address
292 	 * should yield the original BAR value:
293 	 *
294 	 *     resource_to_bus(bus_to_resource(A)) == A
295 	 *
296 	 * If it doesn't, CPU accesses to "bus_to_resource(A)" will not
297 	 * be claimed by the device.
298 	 */
299 	if (inverted_region.start != region.start) {
300 		res->flags |= IORESOURCE_UNSET;
301 		res->start = 0;
302 		res->end = region.end - region.start;
303 		dev_info(&dev->dev, "reg 0x%x: initial BAR value %#010llx invalid\n",
304 			 pos, (unsigned long long)region.start);
305 	}
306 
307 	goto out;
308 
309 
310 fail:
311 	res->flags = 0;
312 out:
313 	if (res->flags)
314 		dev_printk(KERN_DEBUG, &dev->dev, "reg 0x%x: %pR\n", pos, res);
315 
316 	return (res->flags & IORESOURCE_MEM_64) ? 1 : 0;
317 }
318 
pci_read_bases(struct pci_dev * dev,unsigned int howmany,int rom)319 static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
320 {
321 	unsigned int pos, reg;
322 
323 	if (dev->non_compliant_bars)
324 		return;
325 
326 	for (pos = 0; pos < howmany; pos++) {
327 		struct resource *res = &dev->resource[pos];
328 		reg = PCI_BASE_ADDRESS_0 + (pos << 2);
329 		pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
330 	}
331 
332 	if (rom) {
333 		struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
334 		dev->rom_base_reg = rom;
335 		res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
336 				IORESOURCE_READONLY | IORESOURCE_SIZEALIGN;
337 		__pci_read_base(dev, pci_bar_mem32, res, rom);
338 	}
339 }
340 
pci_read_bridge_io(struct pci_bus * child)341 static void pci_read_bridge_io(struct pci_bus *child)
342 {
343 	struct pci_dev *dev = child->self;
344 	u8 io_base_lo, io_limit_lo;
345 	unsigned long io_mask, io_granularity, base, limit;
346 	struct pci_bus_region region;
347 	struct resource *res;
348 
349 	io_mask = PCI_IO_RANGE_MASK;
350 	io_granularity = 0x1000;
351 	if (dev->io_window_1k) {
352 		/* Support 1K I/O space granularity */
353 		io_mask = PCI_IO_1K_RANGE_MASK;
354 		io_granularity = 0x400;
355 	}
356 
357 	res = child->resource[0];
358 	pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
359 	pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
360 	base = (io_base_lo & io_mask) << 8;
361 	limit = (io_limit_lo & io_mask) << 8;
362 
363 	if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
364 		u16 io_base_hi, io_limit_hi;
365 
366 		pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
367 		pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
368 		base |= ((unsigned long) io_base_hi << 16);
369 		limit |= ((unsigned long) io_limit_hi << 16);
370 	}
371 
372 	if (base <= limit) {
373 		res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
374 		region.start = base;
375 		region.end = limit + io_granularity - 1;
376 		pcibios_bus_to_resource(dev->bus, res, &region);
377 		dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
378 	}
379 }
380 
pci_read_bridge_mmio(struct pci_bus * child)381 static void pci_read_bridge_mmio(struct pci_bus *child)
382 {
383 	struct pci_dev *dev = child->self;
384 	u16 mem_base_lo, mem_limit_lo;
385 	unsigned long base, limit;
386 	struct pci_bus_region region;
387 	struct resource *res;
388 
389 	res = child->resource[1];
390 	pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
391 	pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
392 	base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
393 	limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
394 	if (base <= limit) {
395 		res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
396 		region.start = base;
397 		region.end = limit + 0xfffff;
398 		pcibios_bus_to_resource(dev->bus, res, &region);
399 		dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
400 	}
401 }
402 
pci_read_bridge_mmio_pref(struct pci_bus * child)403 static void pci_read_bridge_mmio_pref(struct pci_bus *child)
404 {
405 	struct pci_dev *dev = child->self;
406 	u16 mem_base_lo, mem_limit_lo;
407 	u64 base64, limit64;
408 	pci_bus_addr_t base, limit;
409 	struct pci_bus_region region;
410 	struct resource *res;
411 
412 	res = child->resource[2];
413 	pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
414 	pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
415 	base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
416 	limit64 = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
417 
418 	if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
419 		u32 mem_base_hi, mem_limit_hi;
420 
421 		pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
422 		pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
423 
424 		/*
425 		 * Some bridges set the base > limit by default, and some
426 		 * (broken) BIOSes do not initialize them.  If we find
427 		 * this, just assume they are not being used.
428 		 */
429 		if (mem_base_hi <= mem_limit_hi) {
430 			base64 |= (u64) mem_base_hi << 32;
431 			limit64 |= (u64) mem_limit_hi << 32;
432 		}
433 	}
434 
435 	base = (pci_bus_addr_t) base64;
436 	limit = (pci_bus_addr_t) limit64;
437 
438 	if (base != base64) {
439 		dev_err(&dev->dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
440 			(unsigned long long) base64);
441 		return;
442 	}
443 
444 	if (base <= limit) {
445 		res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
446 					 IORESOURCE_MEM | IORESOURCE_PREFETCH;
447 		if (res->flags & PCI_PREF_RANGE_TYPE_64)
448 			res->flags |= IORESOURCE_MEM_64;
449 		region.start = base;
450 		region.end = limit + 0xfffff;
451 		pcibios_bus_to_resource(dev->bus, res, &region);
452 		dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
453 	}
454 }
455 
pci_read_bridge_bases(struct pci_bus * child)456 void pci_read_bridge_bases(struct pci_bus *child)
457 {
458 	struct pci_dev *dev = child->self;
459 	struct resource *res;
460 	int i;
461 
462 	if (pci_is_root_bus(child))	/* It's a host bus, nothing to read */
463 		return;
464 
465 	dev_info(&dev->dev, "PCI bridge to %pR%s\n",
466 		 &child->busn_res,
467 		 dev->transparent ? " (subtractive decode)" : "");
468 
469 	pci_bus_remove_resources(child);
470 	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++)
471 		child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
472 
473 	pci_read_bridge_io(child);
474 	pci_read_bridge_mmio(child);
475 	pci_read_bridge_mmio_pref(child);
476 
477 	if (dev->transparent) {
478 		pci_bus_for_each_resource(child->parent, res, i) {
479 			if (res && res->flags) {
480 				pci_bus_add_resource(child, res,
481 						     PCI_SUBTRACTIVE_DECODE);
482 				dev_printk(KERN_DEBUG, &dev->dev,
483 					   "  bridge window %pR (subtractive decode)\n",
484 					   res);
485 			}
486 		}
487 	}
488 }
489 
pci_alloc_bus(struct pci_bus * parent)490 static struct pci_bus *pci_alloc_bus(struct pci_bus *parent)
491 {
492 	struct pci_bus *b;
493 
494 	b = kzalloc(sizeof(*b), GFP_KERNEL);
495 	if (!b)
496 		return NULL;
497 
498 	INIT_LIST_HEAD(&b->node);
499 	INIT_LIST_HEAD(&b->children);
500 	INIT_LIST_HEAD(&b->devices);
501 	INIT_LIST_HEAD(&b->slots);
502 	INIT_LIST_HEAD(&b->resources);
503 	b->max_bus_speed = PCI_SPEED_UNKNOWN;
504 	b->cur_bus_speed = PCI_SPEED_UNKNOWN;
505 #ifdef CONFIG_PCI_DOMAINS_GENERIC
506 	if (parent)
507 		b->domain_nr = parent->domain_nr;
508 #endif
509 	return b;
510 }
511 
pci_release_host_bridge_dev(struct device * dev)512 static void pci_release_host_bridge_dev(struct device *dev)
513 {
514 	struct pci_host_bridge *bridge = to_pci_host_bridge(dev);
515 
516 	if (bridge->release_fn)
517 		bridge->release_fn(bridge);
518 
519 	pci_free_resource_list(&bridge->windows);
520 
521 	kfree(bridge);
522 }
523 
pci_alloc_host_bridge(struct pci_bus * b)524 static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b)
525 {
526 	struct pci_host_bridge *bridge;
527 
528 	bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
529 	if (!bridge)
530 		return NULL;
531 
532 	INIT_LIST_HEAD(&bridge->windows);
533 	bridge->bus = b;
534 	return bridge;
535 }
536 
537 static const unsigned char pcix_bus_speed[] = {
538 	PCI_SPEED_UNKNOWN,		/* 0 */
539 	PCI_SPEED_66MHz_PCIX,		/* 1 */
540 	PCI_SPEED_100MHz_PCIX,		/* 2 */
541 	PCI_SPEED_133MHz_PCIX,		/* 3 */
542 	PCI_SPEED_UNKNOWN,		/* 4 */
543 	PCI_SPEED_66MHz_PCIX_ECC,	/* 5 */
544 	PCI_SPEED_100MHz_PCIX_ECC,	/* 6 */
545 	PCI_SPEED_133MHz_PCIX_ECC,	/* 7 */
546 	PCI_SPEED_UNKNOWN,		/* 8 */
547 	PCI_SPEED_66MHz_PCIX_266,	/* 9 */
548 	PCI_SPEED_100MHz_PCIX_266,	/* A */
549 	PCI_SPEED_133MHz_PCIX_266,	/* B */
550 	PCI_SPEED_UNKNOWN,		/* C */
551 	PCI_SPEED_66MHz_PCIX_533,	/* D */
552 	PCI_SPEED_100MHz_PCIX_533,	/* E */
553 	PCI_SPEED_133MHz_PCIX_533	/* F */
554 };
555 
556 const unsigned char pcie_link_speed[] = {
557 	PCI_SPEED_UNKNOWN,		/* 0 */
558 	PCIE_SPEED_2_5GT,		/* 1 */
559 	PCIE_SPEED_5_0GT,		/* 2 */
560 	PCIE_SPEED_8_0GT,		/* 3 */
561 	PCI_SPEED_UNKNOWN,		/* 4 */
562 	PCI_SPEED_UNKNOWN,		/* 5 */
563 	PCI_SPEED_UNKNOWN,		/* 6 */
564 	PCI_SPEED_UNKNOWN,		/* 7 */
565 	PCI_SPEED_UNKNOWN,		/* 8 */
566 	PCI_SPEED_UNKNOWN,		/* 9 */
567 	PCI_SPEED_UNKNOWN,		/* A */
568 	PCI_SPEED_UNKNOWN,		/* B */
569 	PCI_SPEED_UNKNOWN,		/* C */
570 	PCI_SPEED_UNKNOWN,		/* D */
571 	PCI_SPEED_UNKNOWN,		/* E */
572 	PCI_SPEED_UNKNOWN		/* F */
573 };
574 
pcie_update_link_speed(struct pci_bus * bus,u16 linksta)575 void pcie_update_link_speed(struct pci_bus *bus, u16 linksta)
576 {
577 	bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS];
578 }
579 EXPORT_SYMBOL_GPL(pcie_update_link_speed);
580 
581 static unsigned char agp_speeds[] = {
582 	AGP_UNKNOWN,
583 	AGP_1X,
584 	AGP_2X,
585 	AGP_4X,
586 	AGP_8X
587 };
588 
agp_speed(int agp3,int agpstat)589 static enum pci_bus_speed agp_speed(int agp3, int agpstat)
590 {
591 	int index = 0;
592 
593 	if (agpstat & 4)
594 		index = 3;
595 	else if (agpstat & 2)
596 		index = 2;
597 	else if (agpstat & 1)
598 		index = 1;
599 	else
600 		goto out;
601 
602 	if (agp3) {
603 		index += 2;
604 		if (index == 5)
605 			index = 0;
606 	}
607 
608  out:
609 	return agp_speeds[index];
610 }
611 
pci_set_bus_speed(struct pci_bus * bus)612 static void pci_set_bus_speed(struct pci_bus *bus)
613 {
614 	struct pci_dev *bridge = bus->self;
615 	int pos;
616 
617 	pos = pci_find_capability(bridge, PCI_CAP_ID_AGP);
618 	if (!pos)
619 		pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3);
620 	if (pos) {
621 		u32 agpstat, agpcmd;
622 
623 		pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat);
624 		bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7);
625 
626 		pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd);
627 		bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7);
628 	}
629 
630 	pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX);
631 	if (pos) {
632 		u16 status;
633 		enum pci_bus_speed max;
634 
635 		pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS,
636 				     &status);
637 
638 		if (status & PCI_X_SSTATUS_533MHZ) {
639 			max = PCI_SPEED_133MHz_PCIX_533;
640 		} else if (status & PCI_X_SSTATUS_266MHZ) {
641 			max = PCI_SPEED_133MHz_PCIX_266;
642 		} else if (status & PCI_X_SSTATUS_133MHZ) {
643 			if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2)
644 				max = PCI_SPEED_133MHz_PCIX_ECC;
645 			else
646 				max = PCI_SPEED_133MHz_PCIX;
647 		} else {
648 			max = PCI_SPEED_66MHz_PCIX;
649 		}
650 
651 		bus->max_bus_speed = max;
652 		bus->cur_bus_speed = pcix_bus_speed[
653 			(status & PCI_X_SSTATUS_FREQ) >> 6];
654 
655 		return;
656 	}
657 
658 	if (pci_is_pcie(bridge)) {
659 		u32 linkcap;
660 		u16 linksta;
661 
662 		pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap);
663 		bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS];
664 
665 		pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta);
666 		pcie_update_link_speed(bus, linksta);
667 	}
668 }
669 
pci_host_bridge_msi_domain(struct pci_bus * bus)670 static struct irq_domain *pci_host_bridge_msi_domain(struct pci_bus *bus)
671 {
672 	struct irq_domain *d;
673 
674 	/*
675 	 * Any firmware interface that can resolve the msi_domain
676 	 * should be called from here.
677 	 */
678 	d = pci_host_bridge_of_msi_domain(bus);
679 
680 	return d;
681 }
682 
pci_set_bus_msi_domain(struct pci_bus * bus)683 static void pci_set_bus_msi_domain(struct pci_bus *bus)
684 {
685 	struct irq_domain *d;
686 	struct pci_bus *b;
687 
688 	/*
689 	 * The bus can be a root bus, a subordinate bus, or a virtual bus
690 	 * created by an SR-IOV device.  Walk up to the first bridge device
691 	 * found or derive the domain from the host bridge.
692 	 */
693 	for (b = bus, d = NULL; !d && !pci_is_root_bus(b); b = b->parent) {
694 		if (b->self)
695 			d = dev_get_msi_domain(&b->self->dev);
696 	}
697 
698 	if (!d)
699 		d = pci_host_bridge_msi_domain(b);
700 
701 	dev_set_msi_domain(&bus->dev, d);
702 }
703 
pci_alloc_child_bus(struct pci_bus * parent,struct pci_dev * bridge,int busnr)704 static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent,
705 					   struct pci_dev *bridge, int busnr)
706 {
707 	struct pci_bus *child;
708 	int i;
709 	int ret;
710 
711 	/*
712 	 * Allocate a new bus, and inherit stuff from the parent..
713 	 */
714 	child = pci_alloc_bus(parent);
715 	if (!child)
716 		return NULL;
717 
718 	child->parent = parent;
719 	child->ops = parent->ops;
720 	child->msi = parent->msi;
721 	child->sysdata = parent->sysdata;
722 	child->bus_flags = parent->bus_flags;
723 
724 	/* initialize some portions of the bus device, but don't register it
725 	 * now as the parent is not properly set up yet.
726 	 */
727 	child->dev.class = &pcibus_class;
728 	dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr);
729 
730 	/*
731 	 * Set up the primary, secondary and subordinate
732 	 * bus numbers.
733 	 */
734 	child->number = child->busn_res.start = busnr;
735 	child->primary = parent->busn_res.start;
736 	child->busn_res.end = 0xff;
737 
738 	if (!bridge) {
739 		child->dev.parent = parent->bridge;
740 		goto add_dev;
741 	}
742 
743 	child->self = bridge;
744 	child->bridge = get_device(&bridge->dev);
745 	child->dev.parent = child->bridge;
746 	pci_set_bus_of_node(child);
747 	pci_set_bus_speed(child);
748 
749 	/* Set up default resource pointers and names.. */
750 	for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) {
751 		child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
752 		child->resource[i]->name = child->name;
753 	}
754 	bridge->subordinate = child;
755 
756 add_dev:
757 	pci_set_bus_msi_domain(child);
758 	ret = device_register(&child->dev);
759 	WARN_ON(ret < 0);
760 
761 	pcibios_add_bus(child);
762 
763 	/* Create legacy_io and legacy_mem files for this bus */
764 	pci_create_legacy_files(child);
765 
766 	return child;
767 }
768 
pci_add_new_bus(struct pci_bus * parent,struct pci_dev * dev,int busnr)769 struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev,
770 				int busnr)
771 {
772 	struct pci_bus *child;
773 
774 	child = pci_alloc_child_bus(parent, dev, busnr);
775 	if (child) {
776 		down_write(&pci_bus_sem);
777 		list_add_tail(&child->node, &parent->children);
778 		up_write(&pci_bus_sem);
779 	}
780 	return child;
781 }
782 EXPORT_SYMBOL(pci_add_new_bus);
783 
pci_enable_crs(struct pci_dev * pdev)784 static void pci_enable_crs(struct pci_dev *pdev)
785 {
786 	u16 root_cap = 0;
787 
788 	/* Enable CRS Software Visibility if supported */
789 	pcie_capability_read_word(pdev, PCI_EXP_RTCAP, &root_cap);
790 	if (root_cap & PCI_EXP_RTCAP_CRSVIS)
791 		pcie_capability_set_word(pdev, PCI_EXP_RTCTL,
792 					 PCI_EXP_RTCTL_CRSSVE);
793 }
794 
795 /*
796  * If it's a bridge, configure it and scan the bus behind it.
797  * For CardBus bridges, we don't scan behind as the devices will
798  * be handled by the bridge driver itself.
799  *
800  * We need to process bridges in two passes -- first we scan those
801  * already configured by the BIOS and after we are done with all of
802  * them, we proceed to assigning numbers to the remaining buses in
803  * order to avoid overlaps between old and new bus numbers.
804  */
pci_scan_bridge(struct pci_bus * bus,struct pci_dev * dev,int max,int pass)805 int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass)
806 {
807 	struct pci_bus *child;
808 	int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
809 	u32 buses, i, j = 0;
810 	u16 bctl;
811 	u8 primary, secondary, subordinate;
812 	int broken = 0;
813 
814 	pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
815 	primary = buses & 0xFF;
816 	secondary = (buses >> 8) & 0xFF;
817 	subordinate = (buses >> 16) & 0xFF;
818 
819 	dev_dbg(&dev->dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n",
820 		secondary, subordinate, pass);
821 
822 	if (!primary && (primary != bus->number) && secondary && subordinate) {
823 		dev_warn(&dev->dev, "Primary bus is hard wired to 0\n");
824 		primary = bus->number;
825 	}
826 
827 	/* Check if setup is sensible at all */
828 	if (!pass &&
829 	    (primary != bus->number || secondary <= bus->number ||
830 	     secondary > subordinate)) {
831 		dev_info(&dev->dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n",
832 			 secondary, subordinate);
833 		broken = 1;
834 	}
835 
836 	/* Disable MasterAbortMode during probing to avoid reporting
837 	   of bus errors (in some architectures) */
838 	pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
839 	pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
840 			      bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
841 
842 	pci_enable_crs(dev);
843 
844 	if ((secondary || subordinate) && !pcibios_assign_all_busses() &&
845 	    !is_cardbus && !broken) {
846 		unsigned int cmax;
847 		/*
848 		 * Bus already configured by firmware, process it in the first
849 		 * pass and just note the configuration.
850 		 */
851 		if (pass)
852 			goto out;
853 
854 		/*
855 		 * The bus might already exist for two reasons: Either we are
856 		 * rescanning the bus or the bus is reachable through more than
857 		 * one bridge. The second case can happen with the i450NX
858 		 * chipset.
859 		 */
860 		child = pci_find_bus(pci_domain_nr(bus), secondary);
861 		if (!child) {
862 			child = pci_add_new_bus(bus, dev, secondary);
863 			if (!child)
864 				goto out;
865 			child->primary = primary;
866 			pci_bus_insert_busn_res(child, secondary, subordinate);
867 			child->bridge_ctl = bctl;
868 		}
869 
870 		cmax = pci_scan_child_bus(child);
871 		if (cmax > subordinate)
872 			dev_warn(&dev->dev, "bridge has subordinate %02x but max busn %02x\n",
873 				 subordinate, cmax);
874 		/* subordinate should equal child->busn_res.end */
875 		if (subordinate > max)
876 			max = subordinate;
877 	} else {
878 		/*
879 		 * We need to assign a number to this bus which we always
880 		 * do in the second pass.
881 		 */
882 		if (!pass) {
883 			if (pcibios_assign_all_busses() || broken || is_cardbus)
884 				/* Temporarily disable forwarding of the
885 				   configuration cycles on all bridges in
886 				   this bus segment to avoid possible
887 				   conflicts in the second pass between two
888 				   bridges programmed with overlapping
889 				   bus ranges. */
890 				pci_write_config_dword(dev, PCI_PRIMARY_BUS,
891 						       buses & ~0xffffff);
892 			goto out;
893 		}
894 
895 		/* Clear errors */
896 		pci_write_config_word(dev, PCI_STATUS, 0xffff);
897 
898 		/* Prevent assigning a bus number that already exists.
899 		 * This can happen when a bridge is hot-plugged, so in
900 		 * this case we only re-scan this bus. */
901 		child = pci_find_bus(pci_domain_nr(bus), max+1);
902 		if (!child) {
903 			child = pci_add_new_bus(bus, dev, max+1);
904 			if (!child)
905 				goto out;
906 			pci_bus_insert_busn_res(child, max+1, 0xff);
907 		}
908 		max++;
909 		buses = (buses & 0xff000000)
910 		      | ((unsigned int)(child->primary)     <<  0)
911 		      | ((unsigned int)(child->busn_res.start)   <<  8)
912 		      | ((unsigned int)(child->busn_res.end) << 16);
913 
914 		/*
915 		 * yenta.c forces a secondary latency timer of 176.
916 		 * Copy that behaviour here.
917 		 */
918 		if (is_cardbus) {
919 			buses &= ~0xff000000;
920 			buses |= CARDBUS_LATENCY_TIMER << 24;
921 		}
922 
923 		/*
924 		 * We need to blast all three values with a single write.
925 		 */
926 		pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
927 
928 		if (!is_cardbus) {
929 			child->bridge_ctl = bctl;
930 			max = pci_scan_child_bus(child);
931 		} else {
932 			/*
933 			 * For CardBus bridges, we leave 4 bus numbers
934 			 * as cards with a PCI-to-PCI bridge can be
935 			 * inserted later.
936 			 */
937 			for (i = 0; i < CARDBUS_RESERVE_BUSNR; i++) {
938 				struct pci_bus *parent = bus;
939 				if (pci_find_bus(pci_domain_nr(bus),
940 							max+i+1))
941 					break;
942 				while (parent->parent) {
943 					if ((!pcibios_assign_all_busses()) &&
944 					    (parent->busn_res.end > max) &&
945 					    (parent->busn_res.end <= max+i)) {
946 						j = 1;
947 					}
948 					parent = parent->parent;
949 				}
950 				if (j) {
951 					/*
952 					 * Often, there are two cardbus bridges
953 					 * -- try to leave one valid bus number
954 					 * for each one.
955 					 */
956 					i /= 2;
957 					break;
958 				}
959 			}
960 			max += i;
961 		}
962 		/*
963 		 * Set the subordinate bus number to its real value.
964 		 */
965 		pci_bus_update_busn_res_end(child, max);
966 		pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
967 	}
968 
969 	sprintf(child->name,
970 		(is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"),
971 		pci_domain_nr(bus), child->number);
972 
973 	/* Has only triggered on CardBus, fixup is in yenta_socket */
974 	while (bus->parent) {
975 		if ((child->busn_res.end > bus->busn_res.end) ||
976 		    (child->number > bus->busn_res.end) ||
977 		    (child->number < bus->number) ||
978 		    (child->busn_res.end < bus->number)) {
979 			dev_info(&child->dev, "%pR %s hidden behind%s bridge %s %pR\n",
980 				&child->busn_res,
981 				(bus->number > child->busn_res.end &&
982 				 bus->busn_res.end < child->number) ?
983 					"wholly" : "partially",
984 				bus->self->transparent ? " transparent" : "",
985 				dev_name(&bus->dev),
986 				&bus->busn_res);
987 		}
988 		bus = bus->parent;
989 	}
990 
991 out:
992 	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
993 
994 	return max;
995 }
996 EXPORT_SYMBOL(pci_scan_bridge);
997 
998 /*
999  * Read interrupt line and base address registers.
1000  * The architecture-dependent code can tweak these, of course.
1001  */
pci_read_irq(struct pci_dev * dev)1002 static void pci_read_irq(struct pci_dev *dev)
1003 {
1004 	unsigned char irq;
1005 
1006 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
1007 	dev->pin = irq;
1008 	if (irq)
1009 		pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
1010 	dev->irq = irq;
1011 }
1012 
set_pcie_port_type(struct pci_dev * pdev)1013 void set_pcie_port_type(struct pci_dev *pdev)
1014 {
1015 	int pos;
1016 	u16 reg16;
1017 	int type;
1018 	struct pci_dev *parent;
1019 
1020 	pos = pci_find_capability(pdev, PCI_CAP_ID_EXP);
1021 	if (!pos)
1022 		return;
1023 
1024 	pdev->pcie_cap = pos;
1025 	pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, &reg16);
1026 	pdev->pcie_flags_reg = reg16;
1027 	pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, &reg16);
1028 	pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD;
1029 
1030 	/*
1031 	 * A Root Port or a PCI-to-PCIe bridge is always the upstream end
1032 	 * of a Link.  No PCIe component has two Links.  Two Links are
1033 	 * connected by a Switch that has a Port on each Link and internal
1034 	 * logic to connect the two Ports.
1035 	 */
1036 	type = pci_pcie_type(pdev);
1037 	if (type == PCI_EXP_TYPE_ROOT_PORT ||
1038 	    type == PCI_EXP_TYPE_PCIE_BRIDGE)
1039 		pdev->has_secondary_link = 1;
1040 	else if (type == PCI_EXP_TYPE_UPSTREAM ||
1041 		 type == PCI_EXP_TYPE_DOWNSTREAM) {
1042 		parent = pci_upstream_bridge(pdev);
1043 
1044 		/*
1045 		 * Usually there's an upstream device (Root Port or Switch
1046 		 * Downstream Port), but we can't assume one exists.
1047 		 */
1048 		if (parent && !parent->has_secondary_link)
1049 			pdev->has_secondary_link = 1;
1050 	}
1051 }
1052 
set_pcie_hotplug_bridge(struct pci_dev * pdev)1053 void set_pcie_hotplug_bridge(struct pci_dev *pdev)
1054 {
1055 	u32 reg32;
1056 
1057 	pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &reg32);
1058 	if (reg32 & PCI_EXP_SLTCAP_HPC)
1059 		pdev->is_hotplug_bridge = 1;
1060 }
1061 
1062 /**
1063  * pci_ext_cfg_is_aliased - is ext config space just an alias of std config?
1064  * @dev: PCI device
1065  *
1066  * PCI Express to PCI/PCI-X Bridge Specification, rev 1.0, 4.1.4 says that
1067  * when forwarding a type1 configuration request the bridge must check that
1068  * the extended register address field is zero.  The bridge is not permitted
1069  * to forward the transactions and must handle it as an Unsupported Request.
1070  * Some bridges do not follow this rule and simply drop the extended register
1071  * bits, resulting in the standard config space being aliased, every 256
1072  * bytes across the entire configuration space.  Test for this condition by
1073  * comparing the first dword of each potential alias to the vendor/device ID.
1074  * Known offenders:
1075  *   ASM1083/1085 PCIe-to-PCI Reversible Bridge (1b21:1080, rev 01 & 03)
1076  *   AMD/ATI SBx00 PCI to PCI Bridge (1002:4384, rev 40)
1077  */
pci_ext_cfg_is_aliased(struct pci_dev * dev)1078 static bool pci_ext_cfg_is_aliased(struct pci_dev *dev)
1079 {
1080 #ifdef CONFIG_PCI_QUIRKS
1081 	int pos;
1082 	u32 header, tmp;
1083 
1084 	pci_read_config_dword(dev, PCI_VENDOR_ID, &header);
1085 
1086 	for (pos = PCI_CFG_SPACE_SIZE;
1087 	     pos < PCI_CFG_SPACE_EXP_SIZE; pos += PCI_CFG_SPACE_SIZE) {
1088 		if (pci_read_config_dword(dev, pos, &tmp) != PCIBIOS_SUCCESSFUL
1089 		    || header != tmp)
1090 			return false;
1091 	}
1092 
1093 	return true;
1094 #else
1095 	return false;
1096 #endif
1097 }
1098 
1099 /**
1100  * pci_cfg_space_size - get the configuration space size of the PCI device.
1101  * @dev: PCI device
1102  *
1103  * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
1104  * have 4096 bytes.  Even if the device is capable, that doesn't mean we can
1105  * access it.  Maybe we don't have a way to generate extended config space
1106  * accesses, or the device is behind a reverse Express bridge.  So we try
1107  * reading the dword at 0x100 which must either be 0 or a valid extended
1108  * capability header.
1109  */
pci_cfg_space_size_ext(struct pci_dev * dev)1110 static int pci_cfg_space_size_ext(struct pci_dev *dev)
1111 {
1112 	u32 status;
1113 	int pos = PCI_CFG_SPACE_SIZE;
1114 
1115 	if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
1116 		goto fail;
1117 	if (status == 0xffffffff || pci_ext_cfg_is_aliased(dev))
1118 		goto fail;
1119 
1120 	return PCI_CFG_SPACE_EXP_SIZE;
1121 
1122  fail:
1123 	return PCI_CFG_SPACE_SIZE;
1124 }
1125 
pci_cfg_space_size(struct pci_dev * dev)1126 int pci_cfg_space_size(struct pci_dev *dev)
1127 {
1128 	int pos;
1129 	u32 status;
1130 	u16 class;
1131 
1132 	class = dev->class >> 8;
1133 	if (class == PCI_CLASS_BRIDGE_HOST)
1134 		return pci_cfg_space_size_ext(dev);
1135 
1136 	if (!pci_is_pcie(dev)) {
1137 		pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1138 		if (!pos)
1139 			goto fail;
1140 
1141 		pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
1142 		if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
1143 			goto fail;
1144 	}
1145 
1146 	return pci_cfg_space_size_ext(dev);
1147 
1148  fail:
1149 	return PCI_CFG_SPACE_SIZE;
1150 }
1151 
1152 #define LEGACY_IO_RESOURCE	(IORESOURCE_IO | IORESOURCE_PCI_FIXED)
1153 
pci_msi_setup_pci_dev(struct pci_dev * dev)1154 void pci_msi_setup_pci_dev(struct pci_dev *dev)
1155 {
1156 	/*
1157 	 * Disable the MSI hardware to avoid screaming interrupts
1158 	 * during boot.  This is the power on reset default so
1159 	 * usually this should be a noop.
1160 	 */
1161 	dev->msi_cap = pci_find_capability(dev, PCI_CAP_ID_MSI);
1162 	if (dev->msi_cap)
1163 		pci_msi_set_enable(dev, 0);
1164 
1165 	dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX);
1166 	if (dev->msix_cap)
1167 		pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
1168 }
1169 
1170 /**
1171  * pci_setup_device - fill in class and map information of a device
1172  * @dev: the device structure to fill
1173  *
1174  * Initialize the device structure with information about the device's
1175  * vendor,class,memory and IO-space addresses,IRQ lines etc.
1176  * Called at initialisation of the PCI subsystem and by CardBus services.
1177  * Returns 0 on success and negative if unknown type of device (not normal,
1178  * bridge or CardBus).
1179  */
pci_setup_device(struct pci_dev * dev)1180 int pci_setup_device(struct pci_dev *dev)
1181 {
1182 	u32 class;
1183 	u16 cmd;
1184 	u8 hdr_type;
1185 	int pos = 0;
1186 	struct pci_bus_region region;
1187 	struct resource *res;
1188 
1189 	if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
1190 		return -EIO;
1191 
1192 	dev->sysdata = dev->bus->sysdata;
1193 	dev->dev.parent = dev->bus->bridge;
1194 	dev->dev.bus = &pci_bus_type;
1195 	dev->hdr_type = hdr_type & 0x7f;
1196 	dev->multifunction = !!(hdr_type & 0x80);
1197 	dev->error_state = pci_channel_io_normal;
1198 	set_pcie_port_type(dev);
1199 
1200 	pci_dev_assign_slot(dev);
1201 	/* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
1202 	   set this higher, assuming the system even supports it.  */
1203 	dev->dma_mask = 0xffffffff;
1204 
1205 	dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
1206 		     dev->bus->number, PCI_SLOT(dev->devfn),
1207 		     PCI_FUNC(dev->devfn));
1208 
1209 	pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
1210 	dev->revision = class & 0xff;
1211 	dev->class = class >> 8;		    /* upper 3 bytes */
1212 
1213 	dev_printk(KERN_DEBUG, &dev->dev, "[%04x:%04x] type %02x class %#08x\n",
1214 		   dev->vendor, dev->device, dev->hdr_type, dev->class);
1215 
1216 	/* need to have dev->class ready */
1217 	dev->cfg_size = pci_cfg_space_size(dev);
1218 
1219 	/* "Unknown power state" */
1220 	dev->current_state = PCI_UNKNOWN;
1221 
1222 	pci_msi_setup_pci_dev(dev);
1223 
1224 	/* Early fixups, before probing the BARs */
1225 	pci_fixup_device(pci_fixup_early, dev);
1226 	/* device class may be changed after fixup */
1227 	class = dev->class >> 8;
1228 
1229 	if (dev->non_compliant_bars && !dev->mmio_always_on) {
1230 		pci_read_config_word(dev, PCI_COMMAND, &cmd);
1231 		if (cmd & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) {
1232 			dev_info(&dev->dev, "device has non-compliant BARs; disabling IO/MEM decoding\n");
1233 			cmd &= ~PCI_COMMAND_IO;
1234 			cmd &= ~PCI_COMMAND_MEMORY;
1235 			pci_write_config_word(dev, PCI_COMMAND, cmd);
1236 		}
1237 	}
1238 
1239 	switch (dev->hdr_type) {		    /* header type */
1240 	case PCI_HEADER_TYPE_NORMAL:		    /* standard header */
1241 		if (class == PCI_CLASS_BRIDGE_PCI)
1242 			goto bad;
1243 		pci_read_irq(dev);
1244 		pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
1245 		pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1246 		pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
1247 
1248 		/*
1249 		 * Do the ugly legacy mode stuff here rather than broken chip
1250 		 * quirk code. Legacy mode ATA controllers have fixed
1251 		 * addresses. These are not always echoed in BAR0-3, and
1252 		 * BAR0-3 in a few cases contain junk!
1253 		 */
1254 		if (class == PCI_CLASS_STORAGE_IDE) {
1255 			u8 progif;
1256 			pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
1257 			if ((progif & 1) == 0) {
1258 				region.start = 0x1F0;
1259 				region.end = 0x1F7;
1260 				res = &dev->resource[0];
1261 				res->flags = LEGACY_IO_RESOURCE;
1262 				pcibios_bus_to_resource(dev->bus, res, &region);
1263 				dev_info(&dev->dev, "legacy IDE quirk: reg 0x10: %pR\n",
1264 					 res);
1265 				region.start = 0x3F6;
1266 				region.end = 0x3F6;
1267 				res = &dev->resource[1];
1268 				res->flags = LEGACY_IO_RESOURCE;
1269 				pcibios_bus_to_resource(dev->bus, res, &region);
1270 				dev_info(&dev->dev, "legacy IDE quirk: reg 0x14: %pR\n",
1271 					 res);
1272 			}
1273 			if ((progif & 4) == 0) {
1274 				region.start = 0x170;
1275 				region.end = 0x177;
1276 				res = &dev->resource[2];
1277 				res->flags = LEGACY_IO_RESOURCE;
1278 				pcibios_bus_to_resource(dev->bus, res, &region);
1279 				dev_info(&dev->dev, "legacy IDE quirk: reg 0x18: %pR\n",
1280 					 res);
1281 				region.start = 0x376;
1282 				region.end = 0x376;
1283 				res = &dev->resource[3];
1284 				res->flags = LEGACY_IO_RESOURCE;
1285 				pcibios_bus_to_resource(dev->bus, res, &region);
1286 				dev_info(&dev->dev, "legacy IDE quirk: reg 0x1c: %pR\n",
1287 					 res);
1288 			}
1289 		}
1290 		break;
1291 
1292 	case PCI_HEADER_TYPE_BRIDGE:		    /* bridge header */
1293 		if (class != PCI_CLASS_BRIDGE_PCI)
1294 			goto bad;
1295 		/* The PCI-to-PCI bridge spec requires that subtractive
1296 		   decoding (i.e. transparent) bridge must have programming
1297 		   interface code of 0x01. */
1298 		pci_read_irq(dev);
1299 		dev->transparent = ((dev->class & 0xff) == 1);
1300 		pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
1301 		set_pcie_hotplug_bridge(dev);
1302 		pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
1303 		if (pos) {
1304 			pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
1305 			pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
1306 		}
1307 		break;
1308 
1309 	case PCI_HEADER_TYPE_CARDBUS:		    /* CardBus bridge header */
1310 		if (class != PCI_CLASS_BRIDGE_CARDBUS)
1311 			goto bad;
1312 		pci_read_irq(dev);
1313 		pci_read_bases(dev, 1, 0);
1314 		pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
1315 		pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
1316 		break;
1317 
1318 	default:				    /* unknown header */
1319 		dev_err(&dev->dev, "unknown header type %02x, ignoring device\n",
1320 			dev->hdr_type);
1321 		return -EIO;
1322 
1323 	bad:
1324 		dev_err(&dev->dev, "ignoring class %#08x (doesn't match header type %02x)\n",
1325 			dev->class, dev->hdr_type);
1326 		dev->class = PCI_CLASS_NOT_DEFINED << 8;
1327 	}
1328 
1329 	/* We found a fine healthy device, go go go... */
1330 	return 0;
1331 }
1332 
pci_configure_mps(struct pci_dev * dev)1333 static void pci_configure_mps(struct pci_dev *dev)
1334 {
1335 	struct pci_dev *bridge = pci_upstream_bridge(dev);
1336 	int mps, p_mps, rc;
1337 
1338 	if (!pci_is_pcie(dev))
1339 		return;
1340 
1341 	/* MPS and MRRS fields are of type 'RsvdP' for VFs, short-circuit out */
1342 	if (dev->is_virtfn)
1343 		return;
1344 
1345 	/*
1346 	 * For Root Complex Integrated Endpoints, program the maximum
1347 	 * supported value unless limited by the PCIE_BUS_PEER2PEER case.
1348 	 */
1349 	if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) {
1350 		if (pcie_bus_config == PCIE_BUS_PEER2PEER)
1351 			mps = 128;
1352 		else
1353 			mps = 128 << dev->pcie_mpss;
1354 		rc = pcie_set_mps(dev, mps);
1355 		if (rc) {
1356 			dev_warn(&dev->dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
1357 				 mps);
1358 		}
1359 		return;
1360 	}
1361 
1362 	if (!bridge || !pci_is_pcie(bridge))
1363 		return;
1364 
1365 	mps = pcie_get_mps(dev);
1366 	p_mps = pcie_get_mps(bridge);
1367 
1368 	if (mps == p_mps)
1369 		return;
1370 
1371 	if (pcie_bus_config == PCIE_BUS_TUNE_OFF) {
1372 		dev_warn(&dev->dev, "Max Payload Size %d, but upstream %s set to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
1373 			 mps, pci_name(bridge), p_mps);
1374 		return;
1375 	}
1376 
1377 	/*
1378 	 * Fancier MPS configuration is done later by
1379 	 * pcie_bus_configure_settings()
1380 	 */
1381 	if (pcie_bus_config != PCIE_BUS_DEFAULT)
1382 		return;
1383 
1384 	rc = pcie_set_mps(dev, p_mps);
1385 	if (rc) {
1386 		dev_warn(&dev->dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n",
1387 			 p_mps);
1388 		return;
1389 	}
1390 
1391 	dev_info(&dev->dev, "Max Payload Size set to %d (was %d, max %d)\n",
1392 		 p_mps, mps, 128 << dev->pcie_mpss);
1393 }
1394 
1395 static struct hpp_type0 pci_default_type0 = {
1396 	.revision = 1,
1397 	.cache_line_size = 8,
1398 	.latency_timer = 0x40,
1399 	.enable_serr = 0,
1400 	.enable_perr = 0,
1401 };
1402 
program_hpp_type0(struct pci_dev * dev,struct hpp_type0 * hpp)1403 static void program_hpp_type0(struct pci_dev *dev, struct hpp_type0 *hpp)
1404 {
1405 	u16 pci_cmd, pci_bctl;
1406 
1407 	if (!hpp)
1408 		hpp = &pci_default_type0;
1409 
1410 	if (hpp->revision > 1) {
1411 		dev_warn(&dev->dev,
1412 			 "PCI settings rev %d not supported; using defaults\n",
1413 			 hpp->revision);
1414 		hpp = &pci_default_type0;
1415 	}
1416 
1417 	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, hpp->cache_line_size);
1418 	pci_write_config_byte(dev, PCI_LATENCY_TIMER, hpp->latency_timer);
1419 	pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
1420 	if (hpp->enable_serr)
1421 		pci_cmd |= PCI_COMMAND_SERR;
1422 	if (hpp->enable_perr)
1423 		pci_cmd |= PCI_COMMAND_PARITY;
1424 	pci_write_config_word(dev, PCI_COMMAND, pci_cmd);
1425 
1426 	/* Program bridge control value */
1427 	if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
1428 		pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER,
1429 				      hpp->latency_timer);
1430 		pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &pci_bctl);
1431 		if (hpp->enable_serr)
1432 			pci_bctl |= PCI_BRIDGE_CTL_SERR;
1433 		if (hpp->enable_perr)
1434 			pci_bctl |= PCI_BRIDGE_CTL_PARITY;
1435 		pci_write_config_word(dev, PCI_BRIDGE_CONTROL, pci_bctl);
1436 	}
1437 }
1438 
program_hpp_type1(struct pci_dev * dev,struct hpp_type1 * hpp)1439 static void program_hpp_type1(struct pci_dev *dev, struct hpp_type1 *hpp)
1440 {
1441 	int pos;
1442 
1443 	if (!hpp)
1444 		return;
1445 
1446 	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
1447 	if (!pos)
1448 		return;
1449 
1450 	dev_warn(&dev->dev, "PCI-X settings not supported\n");
1451 }
1452 
pcie_root_rcb_set(struct pci_dev * dev)1453 static bool pcie_root_rcb_set(struct pci_dev *dev)
1454 {
1455 	struct pci_dev *rp = pcie_find_root_port(dev);
1456 	u16 lnkctl;
1457 
1458 	if (!rp)
1459 		return false;
1460 
1461 	pcie_capability_read_word(rp, PCI_EXP_LNKCTL, &lnkctl);
1462 	if (lnkctl & PCI_EXP_LNKCTL_RCB)
1463 		return true;
1464 
1465 	return false;
1466 }
1467 
program_hpp_type2(struct pci_dev * dev,struct hpp_type2 * hpp)1468 static void program_hpp_type2(struct pci_dev *dev, struct hpp_type2 *hpp)
1469 {
1470 	int pos;
1471 	u32 reg32;
1472 
1473 	if (!hpp)
1474 		return;
1475 
1476 	if (!pci_is_pcie(dev))
1477 		return;
1478 
1479 	if (hpp->revision > 1) {
1480 		dev_warn(&dev->dev, "PCIe settings rev %d not supported\n",
1481 			 hpp->revision);
1482 		return;
1483 	}
1484 
1485 	/*
1486 	 * Don't allow _HPX to change MPS or MRRS settings.  We manage
1487 	 * those to make sure they're consistent with the rest of the
1488 	 * platform.
1489 	 */
1490 	hpp->pci_exp_devctl_and |= PCI_EXP_DEVCTL_PAYLOAD |
1491 				    PCI_EXP_DEVCTL_READRQ;
1492 	hpp->pci_exp_devctl_or &= ~(PCI_EXP_DEVCTL_PAYLOAD |
1493 				    PCI_EXP_DEVCTL_READRQ);
1494 
1495 	/* Initialize Device Control Register */
1496 	pcie_capability_clear_and_set_word(dev, PCI_EXP_DEVCTL,
1497 			~hpp->pci_exp_devctl_and, hpp->pci_exp_devctl_or);
1498 
1499 	/* Initialize Link Control Register */
1500 	if (pcie_cap_has_lnkctl(dev)) {
1501 
1502 		/*
1503 		 * If the Root Port supports Read Completion Boundary of
1504 		 * 128, set RCB to 128.  Otherwise, clear it.
1505 		 */
1506 		hpp->pci_exp_lnkctl_and |= PCI_EXP_LNKCTL_RCB;
1507 		hpp->pci_exp_lnkctl_or &= ~PCI_EXP_LNKCTL_RCB;
1508 		if (pcie_root_rcb_set(dev))
1509 			hpp->pci_exp_lnkctl_or |= PCI_EXP_LNKCTL_RCB;
1510 
1511 		pcie_capability_clear_and_set_word(dev, PCI_EXP_LNKCTL,
1512 			~hpp->pci_exp_lnkctl_and, hpp->pci_exp_lnkctl_or);
1513 	}
1514 
1515 	/* Find Advanced Error Reporting Enhanced Capability */
1516 	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
1517 	if (!pos)
1518 		return;
1519 
1520 	/* Initialize Uncorrectable Error Mask Register */
1521 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, &reg32);
1522 	reg32 = (reg32 & hpp->unc_err_mask_and) | hpp->unc_err_mask_or;
1523 	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_MASK, reg32);
1524 
1525 	/* Initialize Uncorrectable Error Severity Register */
1526 	pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, &reg32);
1527 	reg32 = (reg32 & hpp->unc_err_sever_and) | hpp->unc_err_sever_or;
1528 	pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_SEVER, reg32);
1529 
1530 	/* Initialize Correctable Error Mask Register */
1531 	pci_read_config_dword(dev, pos + PCI_ERR_COR_MASK, &reg32);
1532 	reg32 = (reg32 & hpp->cor_err_mask_and) | hpp->cor_err_mask_or;
1533 	pci_write_config_dword(dev, pos + PCI_ERR_COR_MASK, reg32);
1534 
1535 	/* Initialize Advanced Error Capabilities and Control Register */
1536 	pci_read_config_dword(dev, pos + PCI_ERR_CAP, &reg32);
1537 	reg32 = (reg32 & hpp->adv_err_cap_and) | hpp->adv_err_cap_or;
1538 	pci_write_config_dword(dev, pos + PCI_ERR_CAP, reg32);
1539 
1540 	/*
1541 	 * FIXME: The following two registers are not supported yet.
1542 	 *
1543 	 *   o Secondary Uncorrectable Error Severity Register
1544 	 *   o Secondary Uncorrectable Error Mask Register
1545 	 */
1546 }
1547 
pci_configure_device(struct pci_dev * dev)1548 static void pci_configure_device(struct pci_dev *dev)
1549 {
1550 	struct hotplug_params hpp;
1551 	int ret;
1552 
1553 	pci_configure_mps(dev);
1554 
1555 	memset(&hpp, 0, sizeof(hpp));
1556 	ret = pci_get_hp_params(dev, &hpp);
1557 	if (ret)
1558 		return;
1559 
1560 	program_hpp_type2(dev, hpp.t2);
1561 	program_hpp_type1(dev, hpp.t1);
1562 	program_hpp_type0(dev, hpp.t0);
1563 }
1564 
pci_release_capabilities(struct pci_dev * dev)1565 static void pci_release_capabilities(struct pci_dev *dev)
1566 {
1567 	pci_vpd_release(dev);
1568 	pci_iov_release(dev);
1569 	pci_free_cap_save_buffers(dev);
1570 }
1571 
1572 /**
1573  * pci_release_dev - free a pci device structure when all users of it are finished.
1574  * @dev: device that's been disconnected
1575  *
1576  * Will be called only by the device core when all users of this pci device are
1577  * done.
1578  */
pci_release_dev(struct device * dev)1579 static void pci_release_dev(struct device *dev)
1580 {
1581 	struct pci_dev *pci_dev;
1582 
1583 	pci_dev = to_pci_dev(dev);
1584 	pci_release_capabilities(pci_dev);
1585 	pci_release_of_node(pci_dev);
1586 	pcibios_release_device(pci_dev);
1587 	pci_bus_put(pci_dev->bus);
1588 	kfree(pci_dev->driver_override);
1589 	kfree(pci_dev);
1590 }
1591 
pci_alloc_dev(struct pci_bus * bus)1592 struct pci_dev *pci_alloc_dev(struct pci_bus *bus)
1593 {
1594 	struct pci_dev *dev;
1595 
1596 	dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
1597 	if (!dev)
1598 		return NULL;
1599 
1600 	INIT_LIST_HEAD(&dev->bus_list);
1601 	dev->dev.type = &pci_dev_type;
1602 	dev->bus = pci_bus_get(bus);
1603 
1604 	return dev;
1605 }
1606 EXPORT_SYMBOL(pci_alloc_dev);
1607 
pci_bus_read_dev_vendor_id(struct pci_bus * bus,int devfn,u32 * l,int crs_timeout)1608 bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
1609 				int crs_timeout)
1610 {
1611 	int delay = 1;
1612 
1613 	if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1614 		return false;
1615 
1616 	/* some broken boards return 0 or ~0 if a slot is empty: */
1617 	if (*l == 0xffffffff || *l == 0x00000000 ||
1618 	    *l == 0x0000ffff || *l == 0xffff0000)
1619 		return false;
1620 
1621 	/*
1622 	 * Configuration Request Retry Status.  Some root ports return the
1623 	 * actual device ID instead of the synthetic ID (0xFFFF) required
1624 	 * by the PCIe spec.  Ignore the device ID and only check for
1625 	 * (vendor id == 1).
1626 	 */
1627 	while ((*l & 0xffff) == 0x0001) {
1628 		if (!crs_timeout)
1629 			return false;
1630 
1631 		msleep(delay);
1632 		delay *= 2;
1633 		if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))
1634 			return false;
1635 		/* Card hasn't responded in 60 seconds?  Must be stuck. */
1636 		if (delay > crs_timeout) {
1637 			printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not responding\n",
1638 			       pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
1639 			       PCI_FUNC(devfn));
1640 			return false;
1641 		}
1642 	}
1643 
1644 	return true;
1645 }
1646 EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
1647 
1648 /*
1649  * Read the config data for a PCI device, sanity-check it
1650  * and fill in the dev structure...
1651  */
pci_scan_device(struct pci_bus * bus,int devfn)1652 static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
1653 {
1654 	struct pci_dev *dev;
1655 	u32 l;
1656 
1657 	if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
1658 		return NULL;
1659 
1660 	dev = pci_alloc_dev(bus);
1661 	if (!dev)
1662 		return NULL;
1663 
1664 	dev->devfn = devfn;
1665 	dev->vendor = l & 0xffff;
1666 	dev->device = (l >> 16) & 0xffff;
1667 
1668 	pci_set_of_node(dev);
1669 
1670 	if (pci_setup_device(dev)) {
1671 		pci_release_of_node(dev);
1672 		pci_bus_put(dev->bus);
1673 		kfree(dev);
1674 		return NULL;
1675 	}
1676 
1677 	return dev;
1678 }
1679 
pci_init_capabilities(struct pci_dev * dev)1680 static void pci_init_capabilities(struct pci_dev *dev)
1681 {
1682 	/* Enhanced Allocation */
1683 	pci_ea_init(dev);
1684 
1685 	/* MSI/MSI-X list */
1686 	pci_msi_init_pci_dev(dev);
1687 
1688 	/* Buffers for saving PCIe and PCI-X capabilities */
1689 	pci_allocate_cap_save_buffers(dev);
1690 
1691 	/* Power Management */
1692 	pci_pm_init(dev);
1693 
1694 	/* Vital Product Data */
1695 	pci_vpd_pci22_init(dev);
1696 
1697 	/* Alternative Routing-ID Forwarding */
1698 	pci_configure_ari(dev);
1699 
1700 	/* Single Root I/O Virtualization */
1701 	pci_iov_init(dev);
1702 
1703 	/* Address Translation Services */
1704 	pci_ats_init(dev);
1705 
1706 	/* Enable ACS P2P upstream forwarding */
1707 	pci_enable_acs(dev);
1708 
1709 	pci_cleanup_aer_error_status_regs(dev);
1710 }
1711 
1712 /*
1713  * This is the equivalent of pci_host_bridge_msi_domain that acts on
1714  * devices. Firmware interfaces that can select the MSI domain on a
1715  * per-device basis should be called from here.
1716  */
pci_dev_msi_domain(struct pci_dev * dev)1717 static struct irq_domain *pci_dev_msi_domain(struct pci_dev *dev)
1718 {
1719 	struct irq_domain *d;
1720 
1721 	/*
1722 	 * If a domain has been set through the pcibios_add_device
1723 	 * callback, then this is the one (platform code knows best).
1724 	 */
1725 	d = dev_get_msi_domain(&dev->dev);
1726 	if (d)
1727 		return d;
1728 
1729 	/*
1730 	 * Let's see if we have a firmware interface able to provide
1731 	 * the domain.
1732 	 */
1733 	d = pci_msi_get_device_domain(dev);
1734 	if (d)
1735 		return d;
1736 
1737 	return NULL;
1738 }
1739 
pci_set_msi_domain(struct pci_dev * dev)1740 static void pci_set_msi_domain(struct pci_dev *dev)
1741 {
1742 	struct irq_domain *d;
1743 
1744 	/*
1745 	 * If the platform or firmware interfaces cannot supply a
1746 	 * device-specific MSI domain, then inherit the default domain
1747 	 * from the host bridge itself.
1748 	 */
1749 	d = pci_dev_msi_domain(dev);
1750 	if (!d)
1751 		d = dev_get_msi_domain(&dev->bus->dev);
1752 
1753 	dev_set_msi_domain(&dev->dev, d);
1754 }
1755 
1756 /**
1757  * pci_dma_configure - Setup DMA configuration
1758  * @dev: ptr to pci_dev struct of the PCI device
1759  *
1760  * Function to update PCI devices's DMA configuration using the same
1761  * info from the OF node or ACPI node of host bridge's parent (if any).
1762  */
pci_dma_configure(struct pci_dev * dev)1763 static void pci_dma_configure(struct pci_dev *dev)
1764 {
1765 	struct device *bridge = pci_get_host_bridge_device(dev);
1766 
1767 	if (IS_ENABLED(CONFIG_OF) &&
1768 		bridge->parent && bridge->parent->of_node) {
1769 			of_dma_configure(&dev->dev, bridge->parent->of_node);
1770 	} else if (has_acpi_companion(bridge)) {
1771 		struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);
1772 		enum dev_dma_attr attr = acpi_get_dma_attr(adev);
1773 
1774 		if (attr == DEV_DMA_NOT_SUPPORTED)
1775 			dev_warn(&dev->dev, "DMA not supported.\n");
1776 		else
1777 			arch_setup_dma_ops(&dev->dev, 0, 0, NULL,
1778 					   attr == DEV_DMA_COHERENT);
1779 	}
1780 
1781 	pci_put_host_bridge_device(bridge);
1782 }
1783 
pci_device_add(struct pci_dev * dev,struct pci_bus * bus)1784 void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
1785 {
1786 	int ret;
1787 
1788 	pci_configure_device(dev);
1789 
1790 	device_initialize(&dev->dev);
1791 	dev->dev.release = pci_release_dev;
1792 
1793 	set_dev_node(&dev->dev, pcibus_to_node(bus));
1794 	dev->dev.dma_mask = &dev->dma_mask;
1795 	dev->dev.dma_parms = &dev->dma_parms;
1796 	dev->dev.coherent_dma_mask = 0xffffffffull;
1797 	pci_dma_configure(dev);
1798 
1799 	pci_set_dma_max_seg_size(dev, 65536);
1800 	pci_set_dma_seg_boundary(dev, 0xffffffff);
1801 
1802 	/* Fix up broken headers */
1803 	pci_fixup_device(pci_fixup_header, dev);
1804 
1805 	/* moved out from quirk header fixup code */
1806 	pci_reassigndev_resource_alignment(dev);
1807 
1808 	/* Clear the state_saved flag. */
1809 	dev->state_saved = false;
1810 
1811 	/* Initialize various capabilities */
1812 	pci_init_capabilities(dev);
1813 
1814 	/*
1815 	 * Add the device to our list of discovered devices
1816 	 * and the bus list for fixup functions, etc.
1817 	 */
1818 	down_write(&pci_bus_sem);
1819 	list_add_tail(&dev->bus_list, &bus->devices);
1820 	up_write(&pci_bus_sem);
1821 
1822 	ret = pcibios_add_device(dev);
1823 	WARN_ON(ret < 0);
1824 
1825 	/* Setup MSI irq domain */
1826 	pci_set_msi_domain(dev);
1827 
1828 	/* Notifier could use PCI capabilities */
1829 	dev->match_driver = false;
1830 	ret = device_add(&dev->dev);
1831 	WARN_ON(ret < 0);
1832 }
1833 
pci_scan_single_device(struct pci_bus * bus,int devfn)1834 struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn)
1835 {
1836 	struct pci_dev *dev;
1837 
1838 	dev = pci_get_slot(bus, devfn);
1839 	if (dev) {
1840 		pci_dev_put(dev);
1841 		return dev;
1842 	}
1843 
1844 	dev = pci_scan_device(bus, devfn);
1845 	if (!dev)
1846 		return NULL;
1847 
1848 	pci_device_add(dev, bus);
1849 
1850 	return dev;
1851 }
1852 EXPORT_SYMBOL(pci_scan_single_device);
1853 
next_fn(struct pci_bus * bus,struct pci_dev * dev,unsigned fn)1854 static unsigned next_fn(struct pci_bus *bus, struct pci_dev *dev, unsigned fn)
1855 {
1856 	int pos;
1857 	u16 cap = 0;
1858 	unsigned next_fn;
1859 
1860 	if (pci_ari_enabled(bus)) {
1861 		if (!dev)
1862 			return 0;
1863 		pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI);
1864 		if (!pos)
1865 			return 0;
1866 
1867 		pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap);
1868 		next_fn = PCI_ARI_CAP_NFN(cap);
1869 		if (next_fn <= fn)
1870 			return 0;	/* protect against malformed list */
1871 
1872 		return next_fn;
1873 	}
1874 
1875 	/* dev may be NULL for non-contiguous multifunction devices */
1876 	if (!dev || dev->multifunction)
1877 		return (fn + 1) % 8;
1878 
1879 	return 0;
1880 }
1881 
only_one_child(struct pci_bus * bus)1882 static int only_one_child(struct pci_bus *bus)
1883 {
1884 	struct pci_dev *parent = bus->self;
1885 
1886 	if (!parent || !pci_is_pcie(parent))
1887 		return 0;
1888 	if (pci_pcie_type(parent) == PCI_EXP_TYPE_ROOT_PORT)
1889 		return 1;
1890 	if (parent->has_secondary_link &&
1891 	    !pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS))
1892 		return 1;
1893 	return 0;
1894 }
1895 
1896 /**
1897  * pci_scan_slot - scan a PCI slot on a bus for devices.
1898  * @bus: PCI bus to scan
1899  * @devfn: slot number to scan (must have zero function.)
1900  *
1901  * Scan a PCI slot on the specified PCI bus for devices, adding
1902  * discovered devices to the @bus->devices list.  New devices
1903  * will not have is_added set.
1904  *
1905  * Returns the number of new devices found.
1906  */
pci_scan_slot(struct pci_bus * bus,int devfn)1907 int pci_scan_slot(struct pci_bus *bus, int devfn)
1908 {
1909 	unsigned fn, nr = 0;
1910 	struct pci_dev *dev;
1911 
1912 	if (only_one_child(bus) && (devfn > 0))
1913 		return 0; /* Already scanned the entire slot */
1914 
1915 	dev = pci_scan_single_device(bus, devfn);
1916 	if (!dev)
1917 		return 0;
1918 	if (!dev->is_added)
1919 		nr++;
1920 
1921 	for (fn = next_fn(bus, dev, 0); fn > 0; fn = next_fn(bus, dev, fn)) {
1922 		dev = pci_scan_single_device(bus, devfn + fn);
1923 		if (dev) {
1924 			if (!dev->is_added)
1925 				nr++;
1926 			dev->multifunction = 1;
1927 		}
1928 	}
1929 
1930 	/* only one slot has pcie device */
1931 	if (bus->self && nr)
1932 		pcie_aspm_init_link_state(bus->self);
1933 
1934 	return nr;
1935 }
1936 EXPORT_SYMBOL(pci_scan_slot);
1937 
pcie_find_smpss(struct pci_dev * dev,void * data)1938 static int pcie_find_smpss(struct pci_dev *dev, void *data)
1939 {
1940 	u8 *smpss = data;
1941 
1942 	if (!pci_is_pcie(dev))
1943 		return 0;
1944 
1945 	/*
1946 	 * We don't have a way to change MPS settings on devices that have
1947 	 * drivers attached.  A hot-added device might support only the minimum
1948 	 * MPS setting (MPS=128).  Therefore, if the fabric contains a bridge
1949 	 * where devices may be hot-added, we limit the fabric MPS to 128 so
1950 	 * hot-added devices will work correctly.
1951 	 *
1952 	 * However, if we hot-add a device to a slot directly below a Root
1953 	 * Port, it's impossible for there to be other existing devices below
1954 	 * the port.  We don't limit the MPS in this case because we can
1955 	 * reconfigure MPS on both the Root Port and the hot-added device,
1956 	 * and there are no other devices involved.
1957 	 *
1958 	 * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA.
1959 	 */
1960 	if (dev->is_hotplug_bridge &&
1961 	    pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
1962 		*smpss = 0;
1963 
1964 	if (*smpss > dev->pcie_mpss)
1965 		*smpss = dev->pcie_mpss;
1966 
1967 	return 0;
1968 }
1969 
pcie_write_mps(struct pci_dev * dev,int mps)1970 static void pcie_write_mps(struct pci_dev *dev, int mps)
1971 {
1972 	int rc;
1973 
1974 	if (pcie_bus_config == PCIE_BUS_PERFORMANCE) {
1975 		mps = 128 << dev->pcie_mpss;
1976 
1977 		if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT &&
1978 		    dev->bus->self)
1979 			/* For "Performance", the assumption is made that
1980 			 * downstream communication will never be larger than
1981 			 * the MRRS.  So, the MPS only needs to be configured
1982 			 * for the upstream communication.  This being the case,
1983 			 * walk from the top down and set the MPS of the child
1984 			 * to that of the parent bus.
1985 			 *
1986 			 * Configure the device MPS with the smaller of the
1987 			 * device MPSS or the bridge MPS (which is assumed to be
1988 			 * properly configured at this point to the largest
1989 			 * allowable MPS based on its parent bus).
1990 			 */
1991 			mps = min(mps, pcie_get_mps(dev->bus->self));
1992 	}
1993 
1994 	rc = pcie_set_mps(dev, mps);
1995 	if (rc)
1996 		dev_err(&dev->dev, "Failed attempting to set the MPS\n");
1997 }
1998 
pcie_write_mrrs(struct pci_dev * dev)1999 static void pcie_write_mrrs(struct pci_dev *dev)
2000 {
2001 	int rc, mrrs;
2002 
2003 	/* In the "safe" case, do not configure the MRRS.  There appear to be
2004 	 * issues with setting MRRS to 0 on a number of devices.
2005 	 */
2006 	if (pcie_bus_config != PCIE_BUS_PERFORMANCE)
2007 		return;
2008 
2009 	/* For Max performance, the MRRS must be set to the largest supported
2010 	 * value.  However, it cannot be configured larger than the MPS the
2011 	 * device or the bus can support.  This should already be properly
2012 	 * configured by a prior call to pcie_write_mps.
2013 	 */
2014 	mrrs = pcie_get_mps(dev);
2015 
2016 	/* MRRS is a R/W register.  Invalid values can be written, but a
2017 	 * subsequent read will verify if the value is acceptable or not.
2018 	 * If the MRRS value provided is not acceptable (e.g., too large),
2019 	 * shrink the value until it is acceptable to the HW.
2020 	 */
2021 	while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) {
2022 		rc = pcie_set_readrq(dev, mrrs);
2023 		if (!rc)
2024 			break;
2025 
2026 		dev_warn(&dev->dev, "Failed attempting to set the MRRS\n");
2027 		mrrs /= 2;
2028 	}
2029 
2030 	if (mrrs < 128)
2031 		dev_err(&dev->dev, "MRRS was unable to be configured with a safe value.  If problems are experienced, try running with pci=pcie_bus_safe\n");
2032 }
2033 
pcie_bus_configure_set(struct pci_dev * dev,void * data)2034 static int pcie_bus_configure_set(struct pci_dev *dev, void *data)
2035 {
2036 	int mps, orig_mps;
2037 
2038 	if (!pci_is_pcie(dev))
2039 		return 0;
2040 
2041 	if (pcie_bus_config == PCIE_BUS_TUNE_OFF ||
2042 	    pcie_bus_config == PCIE_BUS_DEFAULT)
2043 		return 0;
2044 
2045 	mps = 128 << *(u8 *)data;
2046 	orig_mps = pcie_get_mps(dev);
2047 
2048 	pcie_write_mps(dev, mps);
2049 	pcie_write_mrrs(dev);
2050 
2051 	dev_info(&dev->dev, "Max Payload Size set to %4d/%4d (was %4d), Max Read Rq %4d\n",
2052 		 pcie_get_mps(dev), 128 << dev->pcie_mpss,
2053 		 orig_mps, pcie_get_readrq(dev));
2054 
2055 	return 0;
2056 }
2057 
2058 /* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down,
2059  * parents then children fashion.  If this changes, then this code will not
2060  * work as designed.
2061  */
pcie_bus_configure_settings(struct pci_bus * bus)2062 void pcie_bus_configure_settings(struct pci_bus *bus)
2063 {
2064 	u8 smpss = 0;
2065 
2066 	if (!bus->self)
2067 		return;
2068 
2069 	if (!pci_is_pcie(bus->self))
2070 		return;
2071 
2072 	/* FIXME - Peer to peer DMA is possible, though the endpoint would need
2073 	 * to be aware of the MPS of the destination.  To work around this,
2074 	 * simply force the MPS of the entire system to the smallest possible.
2075 	 */
2076 	if (pcie_bus_config == PCIE_BUS_PEER2PEER)
2077 		smpss = 0;
2078 
2079 	if (pcie_bus_config == PCIE_BUS_SAFE) {
2080 		smpss = bus->self->pcie_mpss;
2081 
2082 		pcie_find_smpss(bus->self, &smpss);
2083 		pci_walk_bus(bus, pcie_find_smpss, &smpss);
2084 	}
2085 
2086 	pcie_bus_configure_set(bus->self, &smpss);
2087 	pci_walk_bus(bus, pcie_bus_configure_set, &smpss);
2088 }
2089 EXPORT_SYMBOL_GPL(pcie_bus_configure_settings);
2090 
pci_scan_child_bus(struct pci_bus * bus)2091 unsigned int pci_scan_child_bus(struct pci_bus *bus)
2092 {
2093 	unsigned int devfn, pass, max = bus->busn_res.start;
2094 	struct pci_dev *dev;
2095 
2096 	dev_dbg(&bus->dev, "scanning bus\n");
2097 
2098 	/* Go find them, Rover! */
2099 	for (devfn = 0; devfn < 0x100; devfn += 8)
2100 		pci_scan_slot(bus, devfn);
2101 
2102 	/* Reserve buses for SR-IOV capability. */
2103 	max += pci_iov_bus_range(bus);
2104 
2105 	/*
2106 	 * After performing arch-dependent fixup of the bus, look behind
2107 	 * all PCI-to-PCI bridges on this bus.
2108 	 */
2109 	if (!bus->is_added) {
2110 		dev_dbg(&bus->dev, "fixups for bus\n");
2111 		pcibios_fixup_bus(bus);
2112 		bus->is_added = 1;
2113 	}
2114 
2115 	for (pass = 0; pass < 2; pass++)
2116 		list_for_each_entry(dev, &bus->devices, bus_list) {
2117 			if (pci_is_bridge(dev))
2118 				max = pci_scan_bridge(bus, dev, max, pass);
2119 		}
2120 
2121 	/*
2122 	 * We've scanned the bus and so we know all about what's on
2123 	 * the other side of any bridges that may be on this bus plus
2124 	 * any devices.
2125 	 *
2126 	 * Return how far we've got finding sub-buses.
2127 	 */
2128 	dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max);
2129 	return max;
2130 }
2131 EXPORT_SYMBOL_GPL(pci_scan_child_bus);
2132 
2133 /**
2134  * pcibios_root_bridge_prepare - Platform-specific host bridge setup.
2135  * @bridge: Host bridge to set up.
2136  *
2137  * Default empty implementation.  Replace with an architecture-specific setup
2138  * routine, if necessary.
2139  */
pcibios_root_bridge_prepare(struct pci_host_bridge * bridge)2140 int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
2141 {
2142 	return 0;
2143 }
2144 
pcibios_add_bus(struct pci_bus * bus)2145 void __weak pcibios_add_bus(struct pci_bus *bus)
2146 {
2147 }
2148 
pcibios_remove_bus(struct pci_bus * bus)2149 void __weak pcibios_remove_bus(struct pci_bus *bus)
2150 {
2151 }
2152 
pci_create_root_bus(struct device * parent,int bus,struct pci_ops * ops,void * sysdata,struct list_head * resources)2153 struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
2154 		struct pci_ops *ops, void *sysdata, struct list_head *resources)
2155 {
2156 	int error;
2157 	struct pci_host_bridge *bridge;
2158 	struct pci_bus *b, *b2;
2159 	struct resource_entry *window, *n;
2160 	struct resource *res;
2161 	resource_size_t offset;
2162 	char bus_addr[64];
2163 	char *fmt;
2164 
2165 	b = pci_alloc_bus(NULL);
2166 	if (!b)
2167 		return NULL;
2168 
2169 	b->sysdata = sysdata;
2170 	b->ops = ops;
2171 	b->number = b->busn_res.start = bus;
2172 	pci_bus_assign_domain_nr(b, parent);
2173 	b2 = pci_find_bus(pci_domain_nr(b), bus);
2174 	if (b2) {
2175 		/* If we already got to this bus through a different bridge, ignore it */
2176 		dev_dbg(&b2->dev, "bus already known\n");
2177 		goto err_out;
2178 	}
2179 
2180 	bridge = pci_alloc_host_bridge(b);
2181 	if (!bridge)
2182 		goto err_out;
2183 
2184 	bridge->dev.parent = parent;
2185 	bridge->dev.release = pci_release_host_bridge_dev;
2186 	dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus);
2187 	error = pcibios_root_bridge_prepare(bridge);
2188 	if (error) {
2189 		kfree(bridge);
2190 		goto err_out;
2191 	}
2192 
2193 	error = device_register(&bridge->dev);
2194 	if (error) {
2195 		put_device(&bridge->dev);
2196 		goto err_out;
2197 	}
2198 	b->bridge = get_device(&bridge->dev);
2199 	device_enable_async_suspend(b->bridge);
2200 	pci_set_bus_of_node(b);
2201 	pci_set_bus_msi_domain(b);
2202 
2203 	if (!parent)
2204 		set_dev_node(b->bridge, pcibus_to_node(b));
2205 
2206 	b->dev.class = &pcibus_class;
2207 	b->dev.parent = b->bridge;
2208 	dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
2209 	error = device_register(&b->dev);
2210 	if (error)
2211 		goto class_dev_reg_err;
2212 
2213 	pcibios_add_bus(b);
2214 
2215 	/* Create legacy_io and legacy_mem files for this bus */
2216 	pci_create_legacy_files(b);
2217 
2218 	if (parent)
2219 		dev_info(parent, "PCI host bridge to bus %s\n", dev_name(&b->dev));
2220 	else
2221 		printk(KERN_INFO "PCI host bridge to bus %s\n", dev_name(&b->dev));
2222 
2223 	/* Add initial resources to the bus */
2224 	resource_list_for_each_entry_safe(window, n, resources) {
2225 		list_move_tail(&window->node, &bridge->windows);
2226 		res = window->res;
2227 		offset = window->offset;
2228 		if (res->flags & IORESOURCE_BUS)
2229 			pci_bus_insert_busn_res(b, bus, res->end);
2230 		else
2231 			pci_bus_add_resource(b, res, 0);
2232 		if (offset) {
2233 			if (resource_type(res) == IORESOURCE_IO)
2234 				fmt = " (bus address [%#06llx-%#06llx])";
2235 			else
2236 				fmt = " (bus address [%#010llx-%#010llx])";
2237 			snprintf(bus_addr, sizeof(bus_addr), fmt,
2238 				 (unsigned long long) (res->start - offset),
2239 				 (unsigned long long) (res->end - offset));
2240 		} else
2241 			bus_addr[0] = '\0';
2242 		dev_info(&b->dev, "root bus resource %pR%s\n", res, bus_addr);
2243 	}
2244 
2245 	down_write(&pci_bus_sem);
2246 	list_add_tail(&b->node, &pci_root_buses);
2247 	up_write(&pci_bus_sem);
2248 
2249 	return b;
2250 
2251 class_dev_reg_err:
2252 	put_device(&bridge->dev);
2253 	device_unregister(&bridge->dev);
2254 err_out:
2255 	kfree(b);
2256 	return NULL;
2257 }
2258 EXPORT_SYMBOL_GPL(pci_create_root_bus);
2259 
pci_bus_insert_busn_res(struct pci_bus * b,int bus,int bus_max)2260 int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max)
2261 {
2262 	struct resource *res = &b->busn_res;
2263 	struct resource *parent_res, *conflict;
2264 
2265 	res->start = bus;
2266 	res->end = bus_max;
2267 	res->flags = IORESOURCE_BUS;
2268 
2269 	if (!pci_is_root_bus(b))
2270 		parent_res = &b->parent->busn_res;
2271 	else {
2272 		parent_res = get_pci_domain_busn_res(pci_domain_nr(b));
2273 		res->flags |= IORESOURCE_PCI_FIXED;
2274 	}
2275 
2276 	conflict = request_resource_conflict(parent_res, res);
2277 
2278 	if (conflict)
2279 		dev_printk(KERN_DEBUG, &b->dev,
2280 			   "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n",
2281 			    res, pci_is_root_bus(b) ? "domain " : "",
2282 			    parent_res, conflict->name, conflict);
2283 
2284 	return conflict == NULL;
2285 }
2286 
pci_bus_update_busn_res_end(struct pci_bus * b,int bus_max)2287 int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max)
2288 {
2289 	struct resource *res = &b->busn_res;
2290 	struct resource old_res = *res;
2291 	resource_size_t size;
2292 	int ret;
2293 
2294 	if (res->start > bus_max)
2295 		return -EINVAL;
2296 
2297 	size = bus_max - res->start + 1;
2298 	ret = adjust_resource(res, res->start, size);
2299 	dev_printk(KERN_DEBUG, &b->dev,
2300 			"busn_res: %pR end %s updated to %02x\n",
2301 			&old_res, ret ? "can not be" : "is", bus_max);
2302 
2303 	if (!ret && !res->parent)
2304 		pci_bus_insert_busn_res(b, res->start, res->end);
2305 
2306 	return ret;
2307 }
2308 
pci_bus_release_busn_res(struct pci_bus * b)2309 void pci_bus_release_busn_res(struct pci_bus *b)
2310 {
2311 	struct resource *res = &b->busn_res;
2312 	int ret;
2313 
2314 	if (!res->flags || !res->parent)
2315 		return;
2316 
2317 	ret = release_resource(res);
2318 	dev_printk(KERN_DEBUG, &b->dev,
2319 			"busn_res: %pR %s released\n",
2320 			res, ret ? "can not be" : "is");
2321 }
2322 
pci_scan_root_bus_msi(struct device * parent,int bus,struct pci_ops * ops,void * sysdata,struct list_head * resources,struct msi_controller * msi)2323 struct pci_bus *pci_scan_root_bus_msi(struct device *parent, int bus,
2324 		struct pci_ops *ops, void *sysdata,
2325 		struct list_head *resources, struct msi_controller *msi)
2326 {
2327 	struct resource_entry *window;
2328 	bool found = false;
2329 	struct pci_bus *b;
2330 	int max;
2331 
2332 	resource_list_for_each_entry(window, resources)
2333 		if (window->res->flags & IORESOURCE_BUS) {
2334 			found = true;
2335 			break;
2336 		}
2337 
2338 	b = pci_create_root_bus(parent, bus, ops, sysdata, resources);
2339 	if (!b)
2340 		return NULL;
2341 
2342 	b->msi = msi;
2343 
2344 	if (!found) {
2345 		dev_info(&b->dev,
2346 		 "No busn resource found for root bus, will use [bus %02x-ff]\n",
2347 			bus);
2348 		pci_bus_insert_busn_res(b, bus, 255);
2349 	}
2350 
2351 	max = pci_scan_child_bus(b);
2352 
2353 	if (!found)
2354 		pci_bus_update_busn_res_end(b, max);
2355 
2356 	return b;
2357 }
2358 
pci_scan_root_bus(struct device * parent,int bus,struct pci_ops * ops,void * sysdata,struct list_head * resources)2359 struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
2360 		struct pci_ops *ops, void *sysdata, struct list_head *resources)
2361 {
2362 	return pci_scan_root_bus_msi(parent, bus, ops, sysdata, resources,
2363 				     NULL);
2364 }
2365 EXPORT_SYMBOL(pci_scan_root_bus);
2366 
pci_scan_bus(int bus,struct pci_ops * ops,void * sysdata)2367 struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
2368 					void *sysdata)
2369 {
2370 	LIST_HEAD(resources);
2371 	struct pci_bus *b;
2372 
2373 	pci_add_resource(&resources, &ioport_resource);
2374 	pci_add_resource(&resources, &iomem_resource);
2375 	pci_add_resource(&resources, &busn_resource);
2376 	b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources);
2377 	if (b) {
2378 		pci_scan_child_bus(b);
2379 	} else {
2380 		pci_free_resource_list(&resources);
2381 	}
2382 	return b;
2383 }
2384 EXPORT_SYMBOL(pci_scan_bus);
2385 
2386 /**
2387  * pci_rescan_bus_bridge_resize - scan a PCI bus for devices.
2388  * @bridge: PCI bridge for the bus to scan
2389  *
2390  * Scan a PCI bus and child buses for new devices, add them,
2391  * and enable them, resizing bridge mmio/io resource if necessary
2392  * and possible.  The caller must ensure the child devices are already
2393  * removed for resizing to occur.
2394  *
2395  * Returns the max number of subordinate bus discovered.
2396  */
pci_rescan_bus_bridge_resize(struct pci_dev * bridge)2397 unsigned int pci_rescan_bus_bridge_resize(struct pci_dev *bridge)
2398 {
2399 	unsigned int max;
2400 	struct pci_bus *bus = bridge->subordinate;
2401 
2402 	max = pci_scan_child_bus(bus);
2403 
2404 	pci_assign_unassigned_bridge_resources(bridge);
2405 
2406 	pci_bus_add_devices(bus);
2407 
2408 	return max;
2409 }
2410 
2411 /**
2412  * pci_rescan_bus - scan a PCI bus for devices.
2413  * @bus: PCI bus to scan
2414  *
2415  * Scan a PCI bus and child buses for new devices, adds them,
2416  * and enables them.
2417  *
2418  * Returns the max number of subordinate bus discovered.
2419  */
pci_rescan_bus(struct pci_bus * bus)2420 unsigned int pci_rescan_bus(struct pci_bus *bus)
2421 {
2422 	unsigned int max;
2423 
2424 	max = pci_scan_child_bus(bus);
2425 	pci_assign_unassigned_bus_resources(bus);
2426 	pci_bus_add_devices(bus);
2427 
2428 	return max;
2429 }
2430 EXPORT_SYMBOL_GPL(pci_rescan_bus);
2431 
2432 /*
2433  * pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal
2434  * routines should always be executed under this mutex.
2435  */
2436 static DEFINE_MUTEX(pci_rescan_remove_lock);
2437 
pci_lock_rescan_remove(void)2438 void pci_lock_rescan_remove(void)
2439 {
2440 	mutex_lock(&pci_rescan_remove_lock);
2441 }
2442 EXPORT_SYMBOL_GPL(pci_lock_rescan_remove);
2443 
pci_unlock_rescan_remove(void)2444 void pci_unlock_rescan_remove(void)
2445 {
2446 	mutex_unlock(&pci_rescan_remove_lock);
2447 }
2448 EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove);
2449 
pci_sort_bf_cmp(const struct device * d_a,const struct device * d_b)2450 static int __init pci_sort_bf_cmp(const struct device *d_a,
2451 				  const struct device *d_b)
2452 {
2453 	const struct pci_dev *a = to_pci_dev(d_a);
2454 	const struct pci_dev *b = to_pci_dev(d_b);
2455 
2456 	if      (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
2457 	else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return  1;
2458 
2459 	if      (a->bus->number < b->bus->number) return -1;
2460 	else if (a->bus->number > b->bus->number) return  1;
2461 
2462 	if      (a->devfn < b->devfn) return -1;
2463 	else if (a->devfn > b->devfn) return  1;
2464 
2465 	return 0;
2466 }
2467 
pci_sort_breadthfirst(void)2468 void __init pci_sort_breadthfirst(void)
2469 {
2470 	bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp);
2471 }
2472