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v4.6
 
   1/*
   2 *	drivers/pci/setup-bus.c
   3 *
   4 * Extruded from code written by
   5 *      Dave Rusling (david.rusling@reo.mts.dec.com)
   6 *      David Mosberger (davidm@cs.arizona.edu)
   7 *	David Miller (davem@redhat.com)
   8 *
   9 * Support routines for initializing a PCI subsystem.
  10 */
  11
  12/*
  13 * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
  14 *	     PCI-PCI bridges cleanup, sorted resource allocation.
  15 * Feb 2002, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
  16 *	     Converted to allocation in 3 passes, which gives
  17 *	     tighter packing. Prefetchable range support.
  18 */
  19
  20#include <linux/init.h>
  21#include <linux/kernel.h>
  22#include <linux/module.h>
  23#include <linux/pci.h>
  24#include <linux/errno.h>
  25#include <linux/ioport.h>
  26#include <linux/cache.h>
  27#include <linux/slab.h>
 
  28#include "pci.h"
  29
  30unsigned int pci_flags;
  31
  32struct pci_dev_resource {
  33	struct list_head list;
  34	struct resource *res;
  35	struct pci_dev *dev;
  36	resource_size_t start;
  37	resource_size_t end;
  38	resource_size_t add_size;
  39	resource_size_t min_align;
  40	unsigned long flags;
  41};
  42
  43static void free_list(struct list_head *head)
  44{
  45	struct pci_dev_resource *dev_res, *tmp;
  46
  47	list_for_each_entry_safe(dev_res, tmp, head, list) {
  48		list_del(&dev_res->list);
  49		kfree(dev_res);
  50	}
  51}
  52
  53/**
  54 * add_to_list() - add a new resource tracker to the list
  55 * @head:	Head of the list
  56 * @dev:	device corresponding to which the resource
  57 *		belongs
  58 * @res:	The resource to be tracked
  59 * @add_size:	additional size to be optionally added
  60 *              to the resource
  61 */
  62static int add_to_list(struct list_head *head,
  63		 struct pci_dev *dev, struct resource *res,
  64		 resource_size_t add_size, resource_size_t min_align)
  65{
  66	struct pci_dev_resource *tmp;
  67
  68	tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
  69	if (!tmp) {
  70		pr_warn("add_to_list: kmalloc() failed!\n");
  71		return -ENOMEM;
  72	}
  73
  74	tmp->res = res;
  75	tmp->dev = dev;
  76	tmp->start = res->start;
  77	tmp->end = res->end;
  78	tmp->flags = res->flags;
  79	tmp->add_size = add_size;
  80	tmp->min_align = min_align;
  81
  82	list_add(&tmp->list, head);
  83
  84	return 0;
  85}
  86
  87static void remove_from_list(struct list_head *head,
  88				 struct resource *res)
  89{
  90	struct pci_dev_resource *dev_res, *tmp;
  91
  92	list_for_each_entry_safe(dev_res, tmp, head, list) {
  93		if (dev_res->res == res) {
  94			list_del(&dev_res->list);
  95			kfree(dev_res);
  96			break;
  97		}
  98	}
  99}
 100
 101static struct pci_dev_resource *res_to_dev_res(struct list_head *head,
 102					       struct resource *res)
 103{
 104	struct pci_dev_resource *dev_res;
 105
 106	list_for_each_entry(dev_res, head, list) {
 107		if (dev_res->res == res) {
 108			int idx = res - &dev_res->dev->resource[0];
 109
 110			dev_printk(KERN_DEBUG, &dev_res->dev->dev,
 111				 "res[%d]=%pR res_to_dev_res add_size %llx min_align %llx\n",
 112				 idx, dev_res->res,
 113				 (unsigned long long)dev_res->add_size,
 114				 (unsigned long long)dev_res->min_align);
 115
 116			return dev_res;
 117		}
 118	}
 119
 120	return NULL;
 121}
 122
 123static resource_size_t get_res_add_size(struct list_head *head,
 124					struct resource *res)
 125{
 126	struct pci_dev_resource *dev_res;
 127
 128	dev_res = res_to_dev_res(head, res);
 129	return dev_res ? dev_res->add_size : 0;
 130}
 131
 132static resource_size_t get_res_add_align(struct list_head *head,
 133					 struct resource *res)
 134{
 135	struct pci_dev_resource *dev_res;
 136
 137	dev_res = res_to_dev_res(head, res);
 138	return dev_res ? dev_res->min_align : 0;
 139}
 140
 141
 142/* Sort resources by alignment */
 143static void pdev_sort_resources(struct pci_dev *dev, struct list_head *head)
 144{
 145	int i;
 146
 147	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
 148		struct resource *r;
 149		struct pci_dev_resource *dev_res, *tmp;
 150		resource_size_t r_align;
 151		struct list_head *n;
 152
 153		r = &dev->resource[i];
 154
 155		if (r->flags & IORESOURCE_PCI_FIXED)
 156			continue;
 157
 158		if (!(r->flags) || r->parent)
 159			continue;
 160
 161		r_align = pci_resource_alignment(dev, r);
 162		if (!r_align) {
 163			dev_warn(&dev->dev, "BAR %d: %pR has bogus alignment\n",
 164				 i, r);
 165			continue;
 166		}
 167
 168		tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
 169		if (!tmp)
 170			panic("pdev_sort_resources(): kmalloc() failed!\n");
 171		tmp->res = r;
 172		tmp->dev = dev;
 173
 174		/* fallback is smallest one or list is empty*/
 175		n = head;
 176		list_for_each_entry(dev_res, head, list) {
 177			resource_size_t align;
 178
 179			align = pci_resource_alignment(dev_res->dev,
 180							 dev_res->res);
 181
 182			if (r_align > align) {
 183				n = &dev_res->list;
 184				break;
 185			}
 186		}
 187		/* Insert it just before n*/
 188		list_add_tail(&tmp->list, n);
 189	}
 190}
 191
 192static void __dev_sort_resources(struct pci_dev *dev,
 193				 struct list_head *head)
 194{
 195	u16 class = dev->class >> 8;
 196
 197	/* Don't touch classless devices or host bridges or ioapics.  */
 198	if (class == PCI_CLASS_NOT_DEFINED || class == PCI_CLASS_BRIDGE_HOST)
 199		return;
 200
 201	/* Don't touch ioapic devices already enabled by firmware */
 202	if (class == PCI_CLASS_SYSTEM_PIC) {
 203		u16 command;
 204		pci_read_config_word(dev, PCI_COMMAND, &command);
 205		if (command & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY))
 206			return;
 207	}
 208
 209	pdev_sort_resources(dev, head);
 210}
 211
 212static inline void reset_resource(struct resource *res)
 213{
 214	res->start = 0;
 215	res->end = 0;
 216	res->flags = 0;
 217}
 218
 219/**
 220 * reassign_resources_sorted() - satisfy any additional resource requests
 221 *
 222 * @realloc_head : head of the list tracking requests requiring additional
 223 *             resources
 224 * @head     : head of the list tracking requests with allocated
 225 *             resources
 226 *
 227 * Walk through each element of the realloc_head and try to procure
 228 * additional resources for the element, provided the element
 229 * is in the head list.
 230 */
 231static void reassign_resources_sorted(struct list_head *realloc_head,
 232		struct list_head *head)
 233{
 234	struct resource *res;
 235	struct pci_dev_resource *add_res, *tmp;
 236	struct pci_dev_resource *dev_res;
 237	resource_size_t add_size, align;
 238	int idx;
 239
 240	list_for_each_entry_safe(add_res, tmp, realloc_head, list) {
 241		bool found_match = false;
 242
 243		res = add_res->res;
 244		/* skip resource that has been reset */
 245		if (!res->flags)
 246			goto out;
 247
 248		/* skip this resource if not found in head list */
 249		list_for_each_entry(dev_res, head, list) {
 250			if (dev_res->res == res) {
 251				found_match = true;
 252				break;
 253			}
 254		}
 255		if (!found_match)/* just skip */
 256			continue;
 257
 258		idx = res - &add_res->dev->resource[0];
 259		add_size = add_res->add_size;
 260		align = add_res->min_align;
 261		if (!resource_size(res)) {
 262			res->start = align;
 263			res->end = res->start + add_size - 1;
 264			if (pci_assign_resource(add_res->dev, idx))
 265				reset_resource(res);
 266		} else {
 267			res->flags |= add_res->flags &
 268				 (IORESOURCE_STARTALIGN|IORESOURCE_SIZEALIGN);
 269			if (pci_reassign_resource(add_res->dev, idx,
 270						  add_size, align))
 271				dev_printk(KERN_DEBUG, &add_res->dev->dev,
 272					   "failed to add %llx res[%d]=%pR\n",
 273					   (unsigned long long)add_size,
 274					   idx, res);
 275		}
 276out:
 277		list_del(&add_res->list);
 278		kfree(add_res);
 279	}
 280}
 281
 282/**
 283 * assign_requested_resources_sorted() - satisfy resource requests
 284 *
 285 * @head : head of the list tracking requests for resources
 286 * @fail_head : head of the list tracking requests that could
 287 *		not be allocated
 288 *
 289 * Satisfy resource requests of each element in the list. Add
 290 * requests that could not satisfied to the failed_list.
 291 */
 292static void assign_requested_resources_sorted(struct list_head *head,
 293				 struct list_head *fail_head)
 294{
 295	struct resource *res;
 296	struct pci_dev_resource *dev_res;
 297	int idx;
 298
 299	list_for_each_entry(dev_res, head, list) {
 300		res = dev_res->res;
 301		idx = res - &dev_res->dev->resource[0];
 302		if (resource_size(res) &&
 303		    pci_assign_resource(dev_res->dev, idx)) {
 304			if (fail_head) {
 305				/*
 306				 * if the failed res is for ROM BAR, and it will
 307				 * be enabled later, don't add it to the list
 
 308				 */
 309				if (!((idx == PCI_ROM_RESOURCE) &&
 310				      (!(res->flags & IORESOURCE_ROM_ENABLE))))
 311					add_to_list(fail_head,
 312						    dev_res->dev, res,
 313						    0 /* don't care */,
 314						    0 /* don't care */);
 315			}
 316			reset_resource(res);
 317		}
 318	}
 319}
 320
 321static unsigned long pci_fail_res_type_mask(struct list_head *fail_head)
 322{
 323	struct pci_dev_resource *fail_res;
 324	unsigned long mask = 0;
 325
 326	/* check failed type */
 327	list_for_each_entry(fail_res, fail_head, list)
 328		mask |= fail_res->flags;
 329
 330	/*
 331	 * one pref failed resource will set IORESOURCE_MEM,
 332	 * as we can allocate pref in non-pref range.
 333	 * Will release all assigned non-pref sibling resources
 334	 * according to that bit.
 335	 */
 336	return mask & (IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH);
 337}
 338
 339static bool pci_need_to_release(unsigned long mask, struct resource *res)
 340{
 341	if (res->flags & IORESOURCE_IO)
 342		return !!(mask & IORESOURCE_IO);
 343
 344	/* check pref at first */
 345	if (res->flags & IORESOURCE_PREFETCH) {
 346		if (mask & IORESOURCE_PREFETCH)
 347			return true;
 348		/* count pref if its parent is non-pref */
 349		else if ((mask & IORESOURCE_MEM) &&
 350			 !(res->parent->flags & IORESOURCE_PREFETCH))
 351			return true;
 352		else
 353			return false;
 354	}
 355
 356	if (res->flags & IORESOURCE_MEM)
 357		return !!(mask & IORESOURCE_MEM);
 358
 359	return false;	/* should not get here */
 360}
 361
 362static void __assign_resources_sorted(struct list_head *head,
 363				 struct list_head *realloc_head,
 364				 struct list_head *fail_head)
 365{
 366	/*
 367	 * Should not assign requested resources at first.
 368	 *   they could be adjacent, so later reassign can not reallocate
 369	 *   them one by one in parent resource window.
 370	 * Try to assign requested + add_size at beginning
 371	 *  if could do that, could get out early.
 372	 *  if could not do that, we still try to assign requested at first,
 373	 *    then try to reassign add_size for some resources.
 374	 *
 375	 * Separate three resource type checking if we need to release
 376	 * assigned resource after requested + add_size try.
 377	 *	1. if there is io port assign fail, will release assigned
 378	 *	   io port.
 379	 *	2. if there is pref mmio assign fail, release assigned
 380	 *	   pref mmio.
 381	 *	   if assigned pref mmio's parent is non-pref mmio and there
 382	 *	   is non-pref mmio assign fail, will release that assigned
 383	 *	   pref mmio.
 384	 *	3. if there is non-pref mmio assign fail or pref mmio
 385	 *	   assigned fail, will release assigned non-pref mmio.
 386	 */
 387	LIST_HEAD(save_head);
 388	LIST_HEAD(local_fail_head);
 389	struct pci_dev_resource *save_res;
 390	struct pci_dev_resource *dev_res, *tmp_res, *dev_res2;
 391	unsigned long fail_type;
 392	resource_size_t add_align, align;
 393
 394	/* Check if optional add_size is there */
 395	if (!realloc_head || list_empty(realloc_head))
 396		goto requested_and_reassign;
 397
 398	/* Save original start, end, flags etc at first */
 399	list_for_each_entry(dev_res, head, list) {
 400		if (add_to_list(&save_head, dev_res->dev, dev_res->res, 0, 0)) {
 401			free_list(&save_head);
 402			goto requested_and_reassign;
 403		}
 404	}
 405
 406	/* Update res in head list with add_size in realloc_head list */
 407	list_for_each_entry_safe(dev_res, tmp_res, head, list) {
 408		dev_res->res->end += get_res_add_size(realloc_head,
 409							dev_res->res);
 410
 411		/*
 412		 * There are two kinds of additional resources in the list:
 413		 * 1. bridge resource  -- IORESOURCE_STARTALIGN
 414		 * 2. SR-IOV resource   -- IORESOURCE_SIZEALIGN
 415		 * Here just fix the additional alignment for bridge
 416		 */
 417		if (!(dev_res->res->flags & IORESOURCE_STARTALIGN))
 418			continue;
 419
 420		add_align = get_res_add_align(realloc_head, dev_res->res);
 421
 422		/*
 423		 * The "head" list is sorted by the alignment to make sure
 424		 * resources with bigger alignment will be assigned first.
 425		 * After we change the alignment of a dev_res in "head" list,
 426		 * we need to reorder the list by alignment to make it
 427		 * consistent.
 428		 */
 429		if (add_align > dev_res->res->start) {
 430			resource_size_t r_size = resource_size(dev_res->res);
 431
 432			dev_res->res->start = add_align;
 433			dev_res->res->end = add_align + r_size - 1;
 434
 435			list_for_each_entry(dev_res2, head, list) {
 436				align = pci_resource_alignment(dev_res2->dev,
 437							       dev_res2->res);
 438				if (add_align > align) {
 439					list_move_tail(&dev_res->list,
 440						       &dev_res2->list);
 441					break;
 442				}
 443			}
 444		}
 445
 446	}
 447
 448	/* Try updated head list with add_size added */
 449	assign_requested_resources_sorted(head, &local_fail_head);
 450
 451	/* all assigned with add_size ? */
 452	if (list_empty(&local_fail_head)) {
 453		/* Remove head list from realloc_head list */
 454		list_for_each_entry(dev_res, head, list)
 455			remove_from_list(realloc_head, dev_res->res);
 456		free_list(&save_head);
 457		free_list(head);
 458		return;
 459	}
 460
 461	/* check failed type */
 462	fail_type = pci_fail_res_type_mask(&local_fail_head);
 463	/* remove not need to be released assigned res from head list etc */
 464	list_for_each_entry_safe(dev_res, tmp_res, head, list)
 465		if (dev_res->res->parent &&
 466		    !pci_need_to_release(fail_type, dev_res->res)) {
 467			/* remove it from realloc_head list */
 468			remove_from_list(realloc_head, dev_res->res);
 469			remove_from_list(&save_head, dev_res->res);
 470			list_del(&dev_res->list);
 471			kfree(dev_res);
 472		}
 473
 474	free_list(&local_fail_head);
 475	/* Release assigned resource */
 476	list_for_each_entry(dev_res, head, list)
 477		if (dev_res->res->parent)
 478			release_resource(dev_res->res);
 479	/* Restore start/end/flags from saved list */
 480	list_for_each_entry(save_res, &save_head, list) {
 481		struct resource *res = save_res->res;
 482
 483		res->start = save_res->start;
 484		res->end = save_res->end;
 485		res->flags = save_res->flags;
 486	}
 487	free_list(&save_head);
 488
 489requested_and_reassign:
 490	/* Satisfy the must-have resource requests */
 491	assign_requested_resources_sorted(head, fail_head);
 492
 493	/* Try to satisfy any additional optional resource
 494		requests */
 495	if (realloc_head)
 496		reassign_resources_sorted(realloc_head, head);
 497	free_list(head);
 498}
 499
 500static void pdev_assign_resources_sorted(struct pci_dev *dev,
 501				 struct list_head *add_head,
 502				 struct list_head *fail_head)
 503{
 504	LIST_HEAD(head);
 505
 506	__dev_sort_resources(dev, &head);
 507	__assign_resources_sorted(&head, add_head, fail_head);
 508
 509}
 510
 511static void pbus_assign_resources_sorted(const struct pci_bus *bus,
 512					 struct list_head *realloc_head,
 513					 struct list_head *fail_head)
 514{
 515	struct pci_dev *dev;
 516	LIST_HEAD(head);
 517
 518	list_for_each_entry(dev, &bus->devices, bus_list)
 519		__dev_sort_resources(dev, &head);
 520
 521	__assign_resources_sorted(&head, realloc_head, fail_head);
 522}
 523
 524void pci_setup_cardbus(struct pci_bus *bus)
 525{
 526	struct pci_dev *bridge = bus->self;
 527	struct resource *res;
 528	struct pci_bus_region region;
 529
 530	dev_info(&bridge->dev, "CardBus bridge to %pR\n",
 531		 &bus->busn_res);
 532
 533	res = bus->resource[0];
 534	pcibios_resource_to_bus(bridge->bus, &region, res);
 535	if (res->flags & IORESOURCE_IO) {
 536		/*
 537		 * The IO resource is allocated a range twice as large as it
 538		 * would normally need.  This allows us to set both IO regs.
 539		 */
 540		dev_info(&bridge->dev, "  bridge window %pR\n", res);
 541		pci_write_config_dword(bridge, PCI_CB_IO_BASE_0,
 542					region.start);
 543		pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_0,
 544					region.end);
 545	}
 546
 547	res = bus->resource[1];
 548	pcibios_resource_to_bus(bridge->bus, &region, res);
 549	if (res->flags & IORESOURCE_IO) {
 550		dev_info(&bridge->dev, "  bridge window %pR\n", res);
 551		pci_write_config_dword(bridge, PCI_CB_IO_BASE_1,
 552					region.start);
 553		pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_1,
 554					region.end);
 555	}
 556
 557	res = bus->resource[2];
 558	pcibios_resource_to_bus(bridge->bus, &region, res);
 559	if (res->flags & IORESOURCE_MEM) {
 560		dev_info(&bridge->dev, "  bridge window %pR\n", res);
 561		pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_0,
 562					region.start);
 563		pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_0,
 564					region.end);
 565	}
 566
 567	res = bus->resource[3];
 568	pcibios_resource_to_bus(bridge->bus, &region, res);
 569	if (res->flags & IORESOURCE_MEM) {
 570		dev_info(&bridge->dev, "  bridge window %pR\n", res);
 571		pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_1,
 572					region.start);
 573		pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_1,
 574					region.end);
 575	}
 576}
 577EXPORT_SYMBOL(pci_setup_cardbus);
 578
 579/* Initialize bridges with base/limit values we have collected.
 580   PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998)
 581   requires that if there is no I/O ports or memory behind the
 582   bridge, corresponding range must be turned off by writing base
 583   value greater than limit to the bridge's base/limit registers.
 584
 585   Note: care must be taken when updating I/O base/limit registers
 586   of bridges which support 32-bit I/O. This update requires two
 587   config space writes, so it's quite possible that an I/O window of
 588   the bridge will have some undesirable address (e.g. 0) after the
 589   first write. Ditto 64-bit prefetchable MMIO.  */
 
 
 590static void pci_setup_bridge_io(struct pci_dev *bridge)
 591{
 592	struct resource *res;
 593	struct pci_bus_region region;
 594	unsigned long io_mask;
 595	u8 io_base_lo, io_limit_lo;
 596	u16 l;
 597	u32 io_upper16;
 598
 599	io_mask = PCI_IO_RANGE_MASK;
 600	if (bridge->io_window_1k)
 601		io_mask = PCI_IO_1K_RANGE_MASK;
 602
 603	/* Set up the top and bottom of the PCI I/O segment for this bus. */
 604	res = &bridge->resource[PCI_BRIDGE_RESOURCES + 0];
 605	pcibios_resource_to_bus(bridge->bus, &region, res);
 606	if (res->flags & IORESOURCE_IO) {
 607		pci_read_config_word(bridge, PCI_IO_BASE, &l);
 608		io_base_lo = (region.start >> 8) & io_mask;
 609		io_limit_lo = (region.end >> 8) & io_mask;
 610		l = ((u16) io_limit_lo << 8) | io_base_lo;
 611		/* Set up upper 16 bits of I/O base/limit. */
 612		io_upper16 = (region.end & 0xffff0000) | (region.start >> 16);
 613		dev_info(&bridge->dev, "  bridge window %pR\n", res);
 614	} else {
 615		/* Clear upper 16 bits of I/O base/limit. */
 616		io_upper16 = 0;
 617		l = 0x00f0;
 618	}
 619	/* Temporarily disable the I/O range before updating PCI_IO_BASE. */
 620	pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, 0x0000ffff);
 621	/* Update lower 16 bits of I/O base/limit. */
 622	pci_write_config_word(bridge, PCI_IO_BASE, l);
 623	/* Update upper 16 bits of I/O base/limit. */
 624	pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, io_upper16);
 625}
 626
 627static void pci_setup_bridge_mmio(struct pci_dev *bridge)
 628{
 629	struct resource *res;
 630	struct pci_bus_region region;
 631	u32 l;
 632
 633	/* Set up the top and bottom of the PCI Memory segment for this bus. */
 634	res = &bridge->resource[PCI_BRIDGE_RESOURCES + 1];
 635	pcibios_resource_to_bus(bridge->bus, &region, res);
 636	if (res->flags & IORESOURCE_MEM) {
 637		l = (region.start >> 16) & 0xfff0;
 638		l |= region.end & 0xfff00000;
 639		dev_info(&bridge->dev, "  bridge window %pR\n", res);
 640	} else {
 641		l = 0x0000fff0;
 642	}
 643	pci_write_config_dword(bridge, PCI_MEMORY_BASE, l);
 644}
 645
 646static void pci_setup_bridge_mmio_pref(struct pci_dev *bridge)
 647{
 648	struct resource *res;
 649	struct pci_bus_region region;
 650	u32 l, bu, lu;
 651
 652	/* Clear out the upper 32 bits of PREF limit.
 653	   If PCI_PREF_BASE_UPPER32 was non-zero, this temporarily
 654	   disables PREF range, which is ok. */
 
 
 655	pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, 0);
 656
 657	/* Set up PREF base/limit. */
 658	bu = lu = 0;
 659	res = &bridge->resource[PCI_BRIDGE_RESOURCES + 2];
 660	pcibios_resource_to_bus(bridge->bus, &region, res);
 661	if (res->flags & IORESOURCE_PREFETCH) {
 662		l = (region.start >> 16) & 0xfff0;
 663		l |= region.end & 0xfff00000;
 664		if (res->flags & IORESOURCE_MEM_64) {
 665			bu = upper_32_bits(region.start);
 666			lu = upper_32_bits(region.end);
 667		}
 668		dev_info(&bridge->dev, "  bridge window %pR\n", res);
 669	} else {
 670		l = 0x0000fff0;
 671	}
 672	pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l);
 673
 674	/* Set the upper 32 bits of PREF base & limit. */
 675	pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, bu);
 676	pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, lu);
 677}
 678
 679static void __pci_setup_bridge(struct pci_bus *bus, unsigned long type)
 680{
 681	struct pci_dev *bridge = bus->self;
 682
 683	dev_info(&bridge->dev, "PCI bridge to %pR\n",
 684		 &bus->busn_res);
 685
 686	if (type & IORESOURCE_IO)
 687		pci_setup_bridge_io(bridge);
 688
 689	if (type & IORESOURCE_MEM)
 690		pci_setup_bridge_mmio(bridge);
 691
 692	if (type & IORESOURCE_PREFETCH)
 693		pci_setup_bridge_mmio_pref(bridge);
 694
 695	pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, bus->bridge_ctl);
 696}
 697
 
 
 
 
 698void pci_setup_bridge(struct pci_bus *bus)
 699{
 700	unsigned long type = IORESOURCE_IO | IORESOURCE_MEM |
 701				  IORESOURCE_PREFETCH;
 702
 
 703	__pci_setup_bridge(bus, type);
 704}
 705
 706
 707int pci_claim_bridge_resource(struct pci_dev *bridge, int i)
 708{
 709	if (i < PCI_BRIDGE_RESOURCES || i > PCI_BRIDGE_RESOURCE_END)
 710		return 0;
 711
 712	if (pci_claim_resource(bridge, i) == 0)
 713		return 0;	/* claimed the window */
 714
 715	if ((bridge->class >> 8) != PCI_CLASS_BRIDGE_PCI)
 716		return 0;
 717
 718	if (!pci_bus_clip_resource(bridge, i))
 719		return -EINVAL;	/* clipping didn't change anything */
 720
 721	switch (i - PCI_BRIDGE_RESOURCES) {
 722	case 0:
 723		pci_setup_bridge_io(bridge);
 724		break;
 725	case 1:
 726		pci_setup_bridge_mmio(bridge);
 727		break;
 728	case 2:
 729		pci_setup_bridge_mmio_pref(bridge);
 730		break;
 731	default:
 732		return -EINVAL;
 733	}
 734
 735	if (pci_claim_resource(bridge, i) == 0)
 736		return 0;	/* claimed a smaller window */
 737
 738	return -EINVAL;
 739}
 740
 741/* Check whether the bridge supports optional I/O and
 742   prefetchable memory ranges. If not, the respective
 743   base/limit registers must be read-only and read as 0. */
 
 
 744static void pci_bridge_check_ranges(struct pci_bus *bus)
 745{
 746	u16 io;
 747	u32 pmem;
 748	struct pci_dev *bridge = bus->self;
 749	struct resource *b_res;
 750
 751	b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
 752	b_res[1].flags |= IORESOURCE_MEM;
 753
 754	pci_read_config_word(bridge, PCI_IO_BASE, &io);
 755	if (!io) {
 756		pci_write_config_word(bridge, PCI_IO_BASE, 0xe0f0);
 757		pci_read_config_word(bridge, PCI_IO_BASE, &io);
 758		pci_write_config_word(bridge, PCI_IO_BASE, 0x0);
 759	}
 760	if (io)
 761		b_res[0].flags |= IORESOURCE_IO;
 762
 763	/*  DECchip 21050 pass 2 errata: the bridge may miss an address
 764	    disconnect boundary by one PCI data phase.
 765	    Workaround: do not use prefetching on this device. */
 766	if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001)
 767		return;
 768
 769	pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
 770	if (!pmem) {
 771		pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE,
 772					       0xffe0fff0);
 773		pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem);
 774		pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0);
 775	}
 776	if (pmem) {
 777		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
 778		if ((pmem & PCI_PREF_RANGE_TYPE_MASK) ==
 779		    PCI_PREF_RANGE_TYPE_64) {
 780			b_res[2].flags |= IORESOURCE_MEM_64;
 781			b_res[2].flags |= PCI_PREF_RANGE_TYPE_64;
 782		}
 783	}
 784
 785	/* double check if bridge does support 64 bit pref */
 786	if (b_res[2].flags & IORESOURCE_MEM_64) {
 787		u32 mem_base_hi, tmp;
 788		pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32,
 789					 &mem_base_hi);
 790		pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32,
 791					       0xffffffff);
 792		pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &tmp);
 793		if (!tmp)
 794			b_res[2].flags &= ~IORESOURCE_MEM_64;
 795		pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32,
 796				       mem_base_hi);
 797	}
 798}
 799
 800/* Helper function for sizing routines: find first available
 801   bus resource of a given type. Note: we intentionally skip
 802   the bus resources which have already been assigned (that is,
 803   have non-NULL parent resource). */
 
 804static struct resource *find_free_bus_resource(struct pci_bus *bus,
 805			 unsigned long type_mask, unsigned long type)
 
 806{
 807	int i;
 808	struct resource *r;
 809
 810	pci_bus_for_each_resource(bus, r, i) {
 811		if (r == &ioport_resource || r == &iomem_resource)
 812			continue;
 813		if (r && (r->flags & type_mask) == type && !r->parent)
 814			return r;
 815	}
 816	return NULL;
 817}
 818
 819static resource_size_t calculate_iosize(resource_size_t size,
 820		resource_size_t min_size,
 821		resource_size_t size1,
 822		resource_size_t old_size,
 823		resource_size_t align)
 
 
 824{
 825	if (size < min_size)
 826		size = min_size;
 827	if (old_size == 1)
 828		old_size = 0;
 829	/* To be fixed in 2.5: we should have sort of HAVE_ISA
 830	   flag in the struct pci_bus. */
 
 
 831#if defined(CONFIG_ISA) || defined(CONFIG_EISA)
 832	size = (size & 0xff) + ((size & ~0xffUL) << 2);
 833#endif
 834	size = ALIGN(size + size1, align);
 835	if (size < old_size)
 836		size = old_size;
 
 
 837	return size;
 838}
 839
 840static resource_size_t calculate_memsize(resource_size_t size,
 841		resource_size_t min_size,
 842		resource_size_t size1,
 843		resource_size_t old_size,
 844		resource_size_t align)
 
 845{
 846	if (size < min_size)
 847		size = min_size;
 848	if (old_size == 1)
 849		old_size = 0;
 850	if (size < old_size)
 851		size = old_size;
 852	size = ALIGN(size + size1, align);
 
 853	return size;
 854}
 855
 856resource_size_t __weak pcibios_window_alignment(struct pci_bus *bus,
 857						unsigned long type)
 858{
 859	return 1;
 860}
 861
 862#define PCI_P2P_DEFAULT_MEM_ALIGN	0x100000	/* 1MiB */
 863#define PCI_P2P_DEFAULT_IO_ALIGN	0x1000		/* 4KiB */
 864#define PCI_P2P_DEFAULT_IO_ALIGN_1K	0x400		/* 1KiB */
 865
 866static resource_size_t window_alignment(struct pci_bus *bus,
 867					unsigned long type)
 868{
 869	resource_size_t align = 1, arch_align;
 870
 871	if (type & IORESOURCE_MEM)
 872		align = PCI_P2P_DEFAULT_MEM_ALIGN;
 873	else if (type & IORESOURCE_IO) {
 874		/*
 875		 * Per spec, I/O windows are 4K-aligned, but some
 876		 * bridges have an extension to support 1K alignment.
 877		 */
 878		if (bus->self->io_window_1k)
 879			align = PCI_P2P_DEFAULT_IO_ALIGN_1K;
 880		else
 881			align = PCI_P2P_DEFAULT_IO_ALIGN;
 882	}
 883
 884	arch_align = pcibios_window_alignment(bus, type);
 885	return max(align, arch_align);
 886}
 887
 888/**
 889 * pbus_size_io() - size the io window of a given bus
 890 *
 891 * @bus : the bus
 892 * @min_size : the minimum io window that must to be allocated
 893 * @add_size : additional optional io window
 894 * @realloc_head : track the additional io window on this list
 895 *
 896 * Sizing the IO windows of the PCI-PCI bridge is trivial,
 897 * since these windows have 1K or 4K granularity and the IO ranges
 898 * of non-bridge PCI devices are limited to 256 bytes.
 899 * We must be careful with the ISA aliasing though.
 900 */
 901static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
 902		resource_size_t add_size, struct list_head *realloc_head)
 
 903{
 904	struct pci_dev *dev;
 905	struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO,
 906							IORESOURCE_IO);
 907	resource_size_t size = 0, size0 = 0, size1 = 0;
 908	resource_size_t children_add_size = 0;
 909	resource_size_t min_align, align;
 910
 911	if (!b_res)
 912		return;
 913
 914	min_align = window_alignment(bus, IORESOURCE_IO);
 915	list_for_each_entry(dev, &bus->devices, bus_list) {
 916		int i;
 917
 918		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
 919			struct resource *r = &dev->resource[i];
 920			unsigned long r_size;
 921
 922			if (r->parent || !(r->flags & IORESOURCE_IO))
 923				continue;
 924			r_size = resource_size(r);
 925
 926			if (r_size < 0x400)
 927				/* Might be re-aligned for ISA */
 928				size += r_size;
 929			else
 930				size1 += r_size;
 931
 932			align = pci_resource_alignment(dev, r);
 933			if (align > min_align)
 934				min_align = align;
 935
 936			if (realloc_head)
 937				children_add_size += get_res_add_size(realloc_head, r);
 938		}
 939	}
 940
 941	size0 = calculate_iosize(size, min_size, size1,
 942			resource_size(b_res), min_align);
 943	if (children_add_size > add_size)
 944		add_size = children_add_size;
 945	size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 :
 946		calculate_iosize(size, min_size, add_size + size1,
 947			resource_size(b_res), min_align);
 948	if (!size0 && !size1) {
 949		if (b_res->start || b_res->end)
 950			dev_info(&bus->self->dev, "disabling bridge window %pR to %pR (unused)\n",
 951				 b_res, &bus->busn_res);
 952		b_res->flags = 0;
 953		return;
 954	}
 955
 956	b_res->start = min_align;
 957	b_res->end = b_res->start + size0 - 1;
 958	b_res->flags |= IORESOURCE_STARTALIGN;
 959	if (size1 > size0 && realloc_head) {
 960		add_to_list(realloc_head, bus->self, b_res, size1-size0,
 961			    min_align);
 962		dev_printk(KERN_DEBUG, &bus->self->dev, "bridge window %pR to %pR add_size %llx\n",
 963			   b_res, &bus->busn_res,
 964			   (unsigned long long)size1-size0);
 965	}
 966}
 967
 968static inline resource_size_t calculate_mem_align(resource_size_t *aligns,
 969						  int max_order)
 970{
 971	resource_size_t align = 0;
 972	resource_size_t min_align = 0;
 973	int order;
 974
 975	for (order = 0; order <= max_order; order++) {
 976		resource_size_t align1 = 1;
 977
 978		align1 <<= (order + 20);
 979
 980		if (!align)
 981			min_align = align1;
 982		else if (ALIGN(align + min_align, min_align) < align1)
 983			min_align = align1 >> 1;
 984		align += aligns[order];
 985	}
 986
 987	return min_align;
 988}
 989
 990/**
 991 * pbus_size_mem() - size the memory window of a given bus
 992 *
 993 * @bus : the bus
 994 * @mask: mask the resource flag, then compare it with type
 995 * @type: the type of free resource from bridge
 996 * @type2: second match type
 997 * @type3: third match type
 998 * @min_size : the minimum memory window that must to be allocated
 999 * @add_size : additional optional memory window
1000 * @realloc_head : track the additional memory window on this list
1001 *
1002 * Calculate the size of the bus and minimal alignment which
1003 * guarantees that all child resources fit in this size.
1004 *
1005 * Returns -ENOSPC if there's no available bus resource of the desired type.
1006 * Otherwise, sets the bus resource start/end to indicate the required
1007 * size, adds things to realloc_head (if supplied), and returns 0.
1008 */
1009static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
1010			 unsigned long type, unsigned long type2,
1011			 unsigned long type3,
1012			 resource_size_t min_size, resource_size_t add_size,
1013			 struct list_head *realloc_head)
1014{
1015	struct pci_dev *dev;
1016	resource_size_t min_align, align, size, size0, size1;
1017	resource_size_t aligns[18];	/* Alignments from 1Mb to 128Gb */
1018	int order, max_order;
1019	struct resource *b_res = find_free_bus_resource(bus,
1020					mask | IORESOURCE_PREFETCH, type);
1021	resource_size_t children_add_size = 0;
1022	resource_size_t children_add_align = 0;
1023	resource_size_t add_align = 0;
1024
1025	if (!b_res)
1026		return -ENOSPC;
1027
1028	memset(aligns, 0, sizeof(aligns));
1029	max_order = 0;
1030	size = 0;
1031
1032	list_for_each_entry(dev, &bus->devices, bus_list) {
1033		int i;
1034
1035		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
1036			struct resource *r = &dev->resource[i];
1037			resource_size_t r_size;
1038
1039			if (r->parent || (r->flags & IORESOURCE_PCI_FIXED) ||
1040			    ((r->flags & mask) != type &&
1041			     (r->flags & mask) != type2 &&
1042			     (r->flags & mask) != type3))
1043				continue;
1044			r_size = resource_size(r);
1045#ifdef CONFIG_PCI_IOV
1046			/* put SRIOV requested res to the optional list */
1047			if (realloc_head && i >= PCI_IOV_RESOURCES &&
1048					i <= PCI_IOV_RESOURCE_END) {
1049				add_align = max(pci_resource_alignment(dev, r), add_align);
1050				r->end = r->start - 1;
1051				add_to_list(realloc_head, dev, r, r_size, 0/* don't care */);
1052				children_add_size += r_size;
1053				continue;
1054			}
1055#endif
1056			/*
1057			 * aligns[0] is for 1MB (since bridge memory
1058			 * windows are always at least 1MB aligned), so
1059			 * keep "order" from being negative for smaller
1060			 * resources.
1061			 */
1062			align = pci_resource_alignment(dev, r);
1063			order = __ffs(align) - 20;
1064			if (order < 0)
1065				order = 0;
1066			if (order >= ARRAY_SIZE(aligns)) {
1067				dev_warn(&dev->dev, "disabling BAR %d: %pR (bad alignment %#llx)\n",
1068					 i, r, (unsigned long long) align);
1069				r->flags = 0;
1070				continue;
1071			}
1072			size += r_size;
1073			/* Exclude ranges with size > align from
1074			   calculation of the alignment. */
1075			if (r_size == align)
 
 
1076				aligns[order] += align;
1077			if (order > max_order)
1078				max_order = order;
1079
1080			if (realloc_head) {
1081				children_add_size += get_res_add_size(realloc_head, r);
1082				children_add_align = get_res_add_align(realloc_head, r);
1083				add_align = max(add_align, children_add_align);
1084			}
1085		}
1086	}
1087
1088	min_align = calculate_mem_align(aligns, max_order);
1089	min_align = max(min_align, window_alignment(bus, b_res->flags));
1090	size0 = calculate_memsize(size, min_size, 0, resource_size(b_res), min_align);
1091	add_align = max(min_align, add_align);
1092	if (children_add_size > add_size)
1093		add_size = children_add_size;
1094	size1 = (!realloc_head || (realloc_head && !add_size)) ? size0 :
1095		calculate_memsize(size, min_size, add_size,
1096				resource_size(b_res), add_align);
1097	if (!size0 && !size1) {
1098		if (b_res->start || b_res->end)
1099			dev_info(&bus->self->dev, "disabling bridge window %pR to %pR (unused)\n",
1100				 b_res, &bus->busn_res);
1101		b_res->flags = 0;
1102		return 0;
1103	}
1104	b_res->start = min_align;
1105	b_res->end = size0 + min_align - 1;
1106	b_res->flags |= IORESOURCE_STARTALIGN;
1107	if (size1 > size0 && realloc_head) {
1108		add_to_list(realloc_head, bus->self, b_res, size1-size0, add_align);
1109		dev_printk(KERN_DEBUG, &bus->self->dev, "bridge window %pR to %pR add_size %llx add_align %llx\n",
1110			   b_res, &bus->busn_res,
1111			   (unsigned long long) (size1 - size0),
1112			   (unsigned long long) add_align);
1113	}
1114	return 0;
1115}
1116
1117unsigned long pci_cardbus_resource_alignment(struct resource *res)
1118{
1119	if (res->flags & IORESOURCE_IO)
1120		return pci_cardbus_io_size;
1121	if (res->flags & IORESOURCE_MEM)
1122		return pci_cardbus_mem_size;
1123	return 0;
1124}
1125
1126static void pci_bus_size_cardbus(struct pci_bus *bus,
1127			struct list_head *realloc_head)
1128{
1129	struct pci_dev *bridge = bus->self;
1130	struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
1131	resource_size_t b_res_3_size = pci_cardbus_mem_size * 2;
1132	u16 ctrl;
1133
1134	if (b_res[0].parent)
1135		goto handle_b_res_1;
1136	/*
1137	 * Reserve some resources for CardBus.  We reserve
1138	 * a fixed amount of bus space for CardBus bridges.
1139	 */
1140	b_res[0].start = pci_cardbus_io_size;
1141	b_res[0].end = b_res[0].start + pci_cardbus_io_size - 1;
1142	b_res[0].flags |= IORESOURCE_IO | IORESOURCE_STARTALIGN;
1143	if (realloc_head) {
1144		b_res[0].end -= pci_cardbus_io_size;
1145		add_to_list(realloc_head, bridge, b_res, pci_cardbus_io_size,
1146				pci_cardbus_io_size);
1147	}
1148
1149handle_b_res_1:
1150	if (b_res[1].parent)
1151		goto handle_b_res_2;
1152	b_res[1].start = pci_cardbus_io_size;
1153	b_res[1].end = b_res[1].start + pci_cardbus_io_size - 1;
1154	b_res[1].flags |= IORESOURCE_IO | IORESOURCE_STARTALIGN;
1155	if (realloc_head) {
1156		b_res[1].end -= pci_cardbus_io_size;
1157		add_to_list(realloc_head, bridge, b_res+1, pci_cardbus_io_size,
1158				 pci_cardbus_io_size);
1159	}
1160
1161handle_b_res_2:
1162	/* MEM1 must not be pref mmio */
1163	pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
1164	if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM1) {
1165		ctrl &= ~PCI_CB_BRIDGE_CTL_PREFETCH_MEM1;
1166		pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
1167		pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
1168	}
1169
1170	/*
1171	 * Check whether prefetchable memory is supported
1172	 * by this bridge.
1173	 */
1174	pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
1175	if (!(ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0)) {
1176		ctrl |= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0;
1177		pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
1178		pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
1179	}
1180
1181	if (b_res[2].parent)
1182		goto handle_b_res_3;
1183	/*
1184	 * If we have prefetchable memory support, allocate
1185	 * two regions.  Otherwise, allocate one region of
1186	 * twice the size.
1187	 */
1188	if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) {
1189		b_res[2].start = pci_cardbus_mem_size;
1190		b_res[2].end = b_res[2].start + pci_cardbus_mem_size - 1;
1191		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH |
1192				  IORESOURCE_STARTALIGN;
1193		if (realloc_head) {
1194			b_res[2].end -= pci_cardbus_mem_size;
1195			add_to_list(realloc_head, bridge, b_res+2,
1196				 pci_cardbus_mem_size, pci_cardbus_mem_size);
1197		}
1198
1199		/* reduce that to half */
1200		b_res_3_size = pci_cardbus_mem_size;
1201	}
1202
1203handle_b_res_3:
1204	if (b_res[3].parent)
1205		goto handle_done;
1206	b_res[3].start = pci_cardbus_mem_size;
1207	b_res[3].end = b_res[3].start + b_res_3_size - 1;
1208	b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_STARTALIGN;
1209	if (realloc_head) {
1210		b_res[3].end -= b_res_3_size;
1211		add_to_list(realloc_head, bridge, b_res+3, b_res_3_size,
1212				 pci_cardbus_mem_size);
1213	}
1214
1215handle_done:
1216	;
1217}
1218
1219void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)
1220{
1221	struct pci_dev *dev;
1222	unsigned long mask, prefmask, type2 = 0, type3 = 0;
1223	resource_size_t additional_mem_size = 0, additional_io_size = 0;
1224	struct resource *b_res;
1225	int ret;
1226
1227	list_for_each_entry(dev, &bus->devices, bus_list) {
1228		struct pci_bus *b = dev->subordinate;
1229		if (!b)
1230			continue;
1231
1232		switch (dev->class >> 8) {
1233		case PCI_CLASS_BRIDGE_CARDBUS:
1234			pci_bus_size_cardbus(b, realloc_head);
1235			break;
1236
1237		case PCI_CLASS_BRIDGE_PCI:
1238		default:
1239			__pci_bus_size_bridges(b, realloc_head);
1240			break;
1241		}
1242	}
1243
1244	/* The root bus? */
1245	if (pci_is_root_bus(bus))
1246		return;
1247
1248	switch (bus->self->class >> 8) {
1249	case PCI_CLASS_BRIDGE_CARDBUS:
1250		/* don't size cardbuses yet. */
1251		break;
1252
1253	case PCI_CLASS_BRIDGE_PCI:
1254		pci_bridge_check_ranges(bus);
1255		if (bus->self->is_hotplug_bridge) {
1256			additional_io_size  = pci_hotplug_io_size;
1257			additional_mem_size = pci_hotplug_mem_size;
1258		}
1259		/* Fall through */
1260	default:
1261		pbus_size_io(bus, realloc_head ? 0 : additional_io_size,
1262			     additional_io_size, realloc_head);
1263
1264		/*
1265		 * If there's a 64-bit prefetchable MMIO window, compute
1266		 * the size required to put all 64-bit prefetchable
1267		 * resources in it.
1268		 */
1269		b_res = &bus->self->resource[PCI_BRIDGE_RESOURCES];
1270		mask = IORESOURCE_MEM;
1271		prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH;
1272		if (b_res[2].flags & IORESOURCE_MEM_64) {
1273			prefmask |= IORESOURCE_MEM_64;
1274			ret = pbus_size_mem(bus, prefmask, prefmask,
1275				  prefmask, prefmask,
1276				  realloc_head ? 0 : additional_mem_size,
1277				  additional_mem_size, realloc_head);
1278
1279			/*
1280			 * If successful, all non-prefetchable resources
1281			 * and any 32-bit prefetchable resources will go in
1282			 * the non-prefetchable window.
1283			 */
1284			if (ret == 0) {
1285				mask = prefmask;
1286				type2 = prefmask & ~IORESOURCE_MEM_64;
1287				type3 = prefmask & ~IORESOURCE_PREFETCH;
1288			}
1289		}
1290
1291		/*
1292		 * If there is no 64-bit prefetchable window, compute the
1293		 * size required to put all prefetchable resources in the
1294		 * 32-bit prefetchable window (if there is one).
1295		 */
1296		if (!type2) {
1297			prefmask &= ~IORESOURCE_MEM_64;
1298			ret = pbus_size_mem(bus, prefmask, prefmask,
1299					 prefmask, prefmask,
1300					 realloc_head ? 0 : additional_mem_size,
1301					 additional_mem_size, realloc_head);
1302
1303			/*
1304			 * If successful, only non-prefetchable resources
1305			 * will go in the non-prefetchable window.
1306			 */
1307			if (ret == 0)
1308				mask = prefmask;
1309			else
1310				additional_mem_size += additional_mem_size;
1311
1312			type2 = type3 = IORESOURCE_MEM;
1313		}
1314
1315		/*
1316		 * Compute the size required to put everything else in the
1317		 * non-prefetchable window.  This includes:
1318		 *
1319		 *   - all non-prefetchable resources
1320		 *   - 32-bit prefetchable resources if there's a 64-bit
1321		 *     prefetchable window or no prefetchable window at all
1322		 *   - 64-bit prefetchable resources if there's no
1323		 *     prefetchable window at all
1324		 *
1325		 * Note that the strategy in __pci_assign_resource() must
1326		 * match that used here.  Specifically, we cannot put a
1327		 * 32-bit prefetchable resource in a 64-bit prefetchable
1328		 * window.
1329		 */
1330		pbus_size_mem(bus, mask, IORESOURCE_MEM, type2, type3,
1331				realloc_head ? 0 : additional_mem_size,
1332				additional_mem_size, realloc_head);
1333		break;
1334	}
1335}
1336
1337void pci_bus_size_bridges(struct pci_bus *bus)
1338{
1339	__pci_bus_size_bridges(bus, NULL);
1340}
1341EXPORT_SYMBOL(pci_bus_size_bridges);
1342
1343static void assign_fixed_resource_on_bus(struct pci_bus *b, struct resource *r)
1344{
1345	int i;
1346	struct resource *parent_r;
1347	unsigned long mask = IORESOURCE_IO | IORESOURCE_MEM |
1348			     IORESOURCE_PREFETCH;
1349
1350	pci_bus_for_each_resource(b, parent_r, i) {
1351		if (!parent_r)
1352			continue;
1353
1354		if ((r->flags & mask) == (parent_r->flags & mask) &&
1355		    resource_contains(parent_r, r))
1356			request_resource(parent_r, r);
1357	}
1358}
1359
1360/*
1361 * Try to assign any resources marked as IORESOURCE_PCI_FIXED, as they
1362 * are skipped by pbus_assign_resources_sorted().
1363 */
1364static void pdev_assign_fixed_resources(struct pci_dev *dev)
1365{
1366	int i;
1367
1368	for (i = 0; i <  PCI_NUM_RESOURCES; i++) {
1369		struct pci_bus *b;
1370		struct resource *r = &dev->resource[i];
1371
1372		if (r->parent || !(r->flags & IORESOURCE_PCI_FIXED) ||
1373		    !(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
1374			continue;
1375
1376		b = dev->bus;
1377		while (b && !r->parent) {
1378			assign_fixed_resource_on_bus(b, r);
1379			b = b->parent;
1380		}
1381	}
1382}
1383
1384void __pci_bus_assign_resources(const struct pci_bus *bus,
1385				struct list_head *realloc_head,
1386				struct list_head *fail_head)
1387{
1388	struct pci_bus *b;
1389	struct pci_dev *dev;
1390
1391	pbus_assign_resources_sorted(bus, realloc_head, fail_head);
1392
1393	list_for_each_entry(dev, &bus->devices, bus_list) {
1394		pdev_assign_fixed_resources(dev);
1395
1396		b = dev->subordinate;
1397		if (!b)
1398			continue;
1399
1400		__pci_bus_assign_resources(b, realloc_head, fail_head);
1401
1402		switch (dev->class >> 8) {
1403		case PCI_CLASS_BRIDGE_PCI:
1404			if (!pci_is_enabled(dev))
1405				pci_setup_bridge(b);
1406			break;
1407
1408		case PCI_CLASS_BRIDGE_CARDBUS:
1409			pci_setup_cardbus(b);
1410			break;
1411
1412		default:
1413			dev_info(&dev->dev, "not setting up bridge for bus %04x:%02x\n",
1414				 pci_domain_nr(b), b->number);
1415			break;
1416		}
1417	}
1418}
1419
1420void pci_bus_assign_resources(const struct pci_bus *bus)
1421{
1422	__pci_bus_assign_resources(bus, NULL, NULL);
1423}
1424EXPORT_SYMBOL(pci_bus_assign_resources);
1425
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1426static void __pci_bridge_assign_resources(const struct pci_dev *bridge,
1427					  struct list_head *add_head,
1428					  struct list_head *fail_head)
1429{
1430	struct pci_bus *b;
1431
1432	pdev_assign_resources_sorted((struct pci_dev *)bridge,
1433					 add_head, fail_head);
1434
1435	b = bridge->subordinate;
1436	if (!b)
1437		return;
1438
1439	__pci_bus_assign_resources(b, add_head, fail_head);
1440
1441	switch (bridge->class >> 8) {
1442	case PCI_CLASS_BRIDGE_PCI:
1443		pci_setup_bridge(b);
1444		break;
1445
1446	case PCI_CLASS_BRIDGE_CARDBUS:
1447		pci_setup_cardbus(b);
1448		break;
1449
1450	default:
1451		dev_info(&bridge->dev, "not setting up bridge for bus %04x:%02x\n",
1452			 pci_domain_nr(b), b->number);
1453		break;
1454	}
1455}
 
 
 
 
 
1456static void pci_bridge_release_resources(struct pci_bus *bus,
1457					  unsigned long type)
1458{
1459	struct pci_dev *dev = bus->self;
1460	struct resource *r;
1461	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
1462				  IORESOURCE_PREFETCH | IORESOURCE_MEM_64;
1463	unsigned old_flags = 0;
1464	struct resource *b_res;
1465	int idx = 1;
1466
1467	b_res = &dev->resource[PCI_BRIDGE_RESOURCES];
1468
1469	/*
1470	 *     1. if there is io port assign fail, will release bridge
1471	 *	  io port.
1472	 *     2. if there is non pref mmio assign fail, release bridge
1473	 *	  nonpref mmio.
1474	 *     3. if there is 64bit pref mmio assign fail, and bridge pref
1475	 *	  is 64bit, release bridge pref mmio.
1476	 *     4. if there is pref mmio assign fail, and bridge pref is
1477	 *	  32bit mmio, release bridge pref mmio
1478	 *     5. if there is pref mmio assign fail, and bridge pref is not
1479	 *	  assigned, release bridge nonpref mmio.
1480	 */
1481	if (type & IORESOURCE_IO)
1482		idx = 0;
1483	else if (!(type & IORESOURCE_PREFETCH))
1484		idx = 1;
1485	else if ((type & IORESOURCE_MEM_64) &&
1486		 (b_res[2].flags & IORESOURCE_MEM_64))
1487		idx = 2;
1488	else if (!(b_res[2].flags & IORESOURCE_MEM_64) &&
1489		 (b_res[2].flags & IORESOURCE_PREFETCH))
1490		idx = 2;
1491	else
1492		idx = 1;
1493
1494	r = &b_res[idx];
1495
1496	if (!r->parent)
1497		return;
1498
1499	/*
1500	 * if there are children under that, we should release them
1501	 *  all
1502	 */
1503	release_child_resources(r);
1504	if (!release_resource(r)) {
1505		type = old_flags = r->flags & type_mask;
1506		dev_printk(KERN_DEBUG, &dev->dev, "resource %d %pR released\n",
1507					PCI_BRIDGE_RESOURCES + idx, r);
1508		/* keep the old size */
1509		r->end = resource_size(r) - 1;
1510		r->start = 0;
1511		r->flags = 0;
1512
1513		/* avoiding touch the one without PREF */
1514		if (type & IORESOURCE_PREFETCH)
1515			type = IORESOURCE_PREFETCH;
1516		__pci_setup_bridge(bus, type);
1517		/* for next child res under same bridge */
1518		r->flags = old_flags;
1519	}
1520}
1521
1522enum release_type {
1523	leaf_only,
1524	whole_subtree,
1525};
 
1526/*
1527 * try to release pci bridge resources that is from leaf bridge,
1528 * so we can allocate big new one later
1529 */
1530static void pci_bus_release_bridge_resources(struct pci_bus *bus,
1531					     unsigned long type,
1532					     enum release_type rel_type)
1533{
1534	struct pci_dev *dev;
1535	bool is_leaf_bridge = true;
1536
1537	list_for_each_entry(dev, &bus->devices, bus_list) {
1538		struct pci_bus *b = dev->subordinate;
1539		if (!b)
1540			continue;
1541
1542		is_leaf_bridge = false;
1543
1544		if ((dev->class >> 8) != PCI_CLASS_BRIDGE_PCI)
1545			continue;
1546
1547		if (rel_type == whole_subtree)
1548			pci_bus_release_bridge_resources(b, type,
1549						 whole_subtree);
1550	}
1551
1552	if (pci_is_root_bus(bus))
1553		return;
1554
1555	if ((bus->self->class >> 8) != PCI_CLASS_BRIDGE_PCI)
1556		return;
1557
1558	if ((rel_type == whole_subtree) || is_leaf_bridge)
1559		pci_bridge_release_resources(bus, type);
1560}
1561
1562static void pci_bus_dump_res(struct pci_bus *bus)
1563{
1564	struct resource *res;
1565	int i;
1566
1567	pci_bus_for_each_resource(bus, res, i) {
1568		if (!res || !res->end || !res->flags)
1569			continue;
1570
1571		dev_printk(KERN_DEBUG, &bus->dev, "resource %d %pR\n", i, res);
1572	}
1573}
1574
1575static void pci_bus_dump_resources(struct pci_bus *bus)
1576{
1577	struct pci_bus *b;
1578	struct pci_dev *dev;
1579
1580
1581	pci_bus_dump_res(bus);
1582
1583	list_for_each_entry(dev, &bus->devices, bus_list) {
1584		b = dev->subordinate;
1585		if (!b)
1586			continue;
1587
1588		pci_bus_dump_resources(b);
1589	}
1590}
1591
1592static int pci_bus_get_depth(struct pci_bus *bus)
1593{
1594	int depth = 0;
1595	struct pci_bus *child_bus;
1596
1597	list_for_each_entry(child_bus, &bus->children, node) {
1598		int ret;
1599
1600		ret = pci_bus_get_depth(child_bus);
1601		if (ret + 1 > depth)
1602			depth = ret + 1;
1603	}
1604
1605	return depth;
1606}
1607
1608/*
1609 * -1: undefined, will auto detect later
1610 *  0: disabled by user
1611 *  1: disabled by auto detect
1612 *  2: enabled by user
1613 *  3: enabled by auto detect
1614 */
1615enum enable_type {
1616	undefined = -1,
1617	user_disabled,
1618	auto_disabled,
1619	user_enabled,
1620	auto_enabled,
1621};
1622
1623static enum enable_type pci_realloc_enable = undefined;
1624void __init pci_realloc_get_opt(char *str)
1625{
1626	if (!strncmp(str, "off", 3))
1627		pci_realloc_enable = user_disabled;
1628	else if (!strncmp(str, "on", 2))
1629		pci_realloc_enable = user_enabled;
1630}
1631static bool pci_realloc_enabled(enum enable_type enable)
1632{
1633	return enable >= user_enabled;
1634}
1635
1636#if defined(CONFIG_PCI_IOV) && defined(CONFIG_PCI_REALLOC_ENABLE_AUTO)
1637static int iov_resources_unassigned(struct pci_dev *dev, void *data)
1638{
1639	int i;
1640	bool *unassigned = data;
1641
1642	for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++) {
1643		struct resource *r = &dev->resource[i];
1644		struct pci_bus_region region;
1645
1646		/* Not assigned or rejected by kernel? */
1647		if (!r->flags)
1648			continue;
1649
1650		pcibios_resource_to_bus(dev->bus, &region, r);
1651		if (!region.start) {
1652			*unassigned = true;
1653			return 1; /* return early from pci_walk_bus() */
1654		}
1655	}
1656
1657	return 0;
1658}
1659
1660static enum enable_type pci_realloc_detect(struct pci_bus *bus,
1661			 enum enable_type enable_local)
1662{
1663	bool unassigned = false;
 
1664
1665	if (enable_local != undefined)
1666		return enable_local;
1667
 
 
 
 
1668	pci_walk_bus(bus, iov_resources_unassigned, &unassigned);
1669	if (unassigned)
1670		return auto_enabled;
1671
1672	return enable_local;
1673}
1674#else
1675static enum enable_type pci_realloc_detect(struct pci_bus *bus,
1676			 enum enable_type enable_local)
1677{
1678	return enable_local;
1679}
1680#endif
1681
1682/*
1683 * first try will not touch pci bridge res
1684 * second and later try will clear small leaf bridge res
1685 * will stop till to the max depth if can not find good one
1686 */
1687void pci_assign_unassigned_root_bus_resources(struct pci_bus *bus)
1688{
1689	LIST_HEAD(realloc_head); /* list of resources that
1690					want additional resources */
1691	struct list_head *add_list = NULL;
1692	int tried_times = 0;
1693	enum release_type rel_type = leaf_only;
1694	LIST_HEAD(fail_head);
1695	struct pci_dev_resource *fail_res;
1696	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
1697				  IORESOURCE_PREFETCH | IORESOURCE_MEM_64;
1698	int pci_try_num = 1;
1699	enum enable_type enable_local;
1700
1701	/* don't realloc if asked to do so */
1702	enable_local = pci_realloc_detect(bus, pci_realloc_enable);
1703	if (pci_realloc_enabled(enable_local)) {
1704		int max_depth = pci_bus_get_depth(bus);
1705
1706		pci_try_num = max_depth + 1;
1707		dev_printk(KERN_DEBUG, &bus->dev,
1708			   "max bus depth: %d pci_try_num: %d\n",
1709			   max_depth, pci_try_num);
1710	}
1711
1712again:
1713	/*
1714	 * last try will use add_list, otherwise will try good to have as
1715	 * must have, so can realloc parent bridge resource
1716	 */
1717	if (tried_times + 1 == pci_try_num)
1718		add_list = &realloc_head;
1719	/* Depth first, calculate sizes and alignments of all
1720	   subordinate buses. */
 
1721	__pci_bus_size_bridges(bus, add_list);
1722
1723	/* Depth last, allocate resources and update the hardware. */
1724	__pci_bus_assign_resources(bus, add_list, &fail_head);
1725	if (add_list)
1726		BUG_ON(!list_empty(add_list));
1727	tried_times++;
1728
1729	/* any device complain? */
1730	if (list_empty(&fail_head))
1731		goto dump;
1732
1733	if (tried_times >= pci_try_num) {
1734		if (enable_local == undefined)
1735			dev_info(&bus->dev, "Some PCI device resources are unassigned, try booting with pci=realloc\n");
1736		else if (enable_local == auto_enabled)
1737			dev_info(&bus->dev, "Automatically enabled pci realloc, if you have problem, try booting with pci=realloc=off\n");
1738
1739		free_list(&fail_head);
1740		goto dump;
1741	}
1742
1743	dev_printk(KERN_DEBUG, &bus->dev,
1744		   "No. %d try to assign unassigned res\n", tried_times + 1);
1745
1746	/* third times and later will not check if it is leaf */
1747	if ((tried_times + 1) > 2)
1748		rel_type = whole_subtree;
1749
1750	/*
1751	 * Try to release leaf bridge's resources that doesn't fit resource of
1752	 * child device under that bridge
1753	 */
1754	list_for_each_entry(fail_res, &fail_head, list)
1755		pci_bus_release_bridge_resources(fail_res->dev->bus,
1756						 fail_res->flags & type_mask,
1757						 rel_type);
1758
1759	/* restore size and flags */
1760	list_for_each_entry(fail_res, &fail_head, list) {
1761		struct resource *res = fail_res->res;
1762
1763		res->start = fail_res->start;
1764		res->end = fail_res->end;
1765		res->flags = fail_res->flags;
1766		if (fail_res->dev->subordinate)
1767			res->flags = 0;
1768	}
1769	free_list(&fail_head);
1770
1771	goto again;
1772
1773dump:
1774	/* dump the resource on buses */
1775	pci_bus_dump_resources(bus);
1776}
1777
1778void __init pci_assign_unassigned_resources(void)
1779{
1780	struct pci_bus *root_bus;
1781
1782	list_for_each_entry(root_bus, &pci_root_buses, node)
1783		pci_assign_unassigned_root_bus_resources(root_bus);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1784}
1785
1786void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge)
1787{
1788	struct pci_bus *parent = bridge->subordinate;
1789	LIST_HEAD(add_list); /* list of resources that
1790					want additional resources */
 
1791	int tried_times = 0;
1792	LIST_HEAD(fail_head);
1793	struct pci_dev_resource *fail_res;
1794	int retval;
1795	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
1796				  IORESOURCE_PREFETCH | IORESOURCE_MEM_64;
1797
1798again:
1799	__pci_bus_size_bridges(parent, &add_list);
 
 
 
 
 
 
 
 
1800	__pci_bridge_assign_resources(bridge, &add_list, &fail_head);
1801	BUG_ON(!list_empty(&add_list));
1802	tried_times++;
1803
1804	if (list_empty(&fail_head))
1805		goto enable_all;
1806
1807	if (tried_times >= 2) {
1808		/* still fail, don't need to try more */
1809		free_list(&fail_head);
1810		goto enable_all;
1811	}
1812
1813	printk(KERN_DEBUG "PCI: No. %d try to assign unassigned res\n",
1814			 tried_times + 1);
1815
1816	/*
1817	 * Try to release leaf bridge's resources that doesn't fit resource of
1818	 * child device under that bridge
1819	 */
1820	list_for_each_entry(fail_res, &fail_head, list)
1821		pci_bus_release_bridge_resources(fail_res->dev->bus,
1822						 fail_res->flags & type_mask,
1823						 whole_subtree);
1824
1825	/* restore size and flags */
1826	list_for_each_entry(fail_res, &fail_head, list) {
1827		struct resource *res = fail_res->res;
1828
1829		res->start = fail_res->start;
1830		res->end = fail_res->end;
1831		res->flags = fail_res->flags;
1832		if (fail_res->dev->subordinate)
1833			res->flags = 0;
1834	}
1835	free_list(&fail_head);
1836
1837	goto again;
1838
1839enable_all:
1840	retval = pci_reenable_device(bridge);
1841	if (retval)
1842		dev_err(&bridge->dev, "Error reenabling bridge (%d)\n", retval);
1843	pci_set_master(bridge);
1844}
1845EXPORT_SYMBOL_GPL(pci_assign_unassigned_bridge_resources);
1846
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1847void pci_assign_unassigned_bus_resources(struct pci_bus *bus)
1848{
1849	struct pci_dev *dev;
1850	LIST_HEAD(add_list); /* list of resources that
1851					want additional resources */
1852
1853	down_read(&pci_bus_sem);
1854	list_for_each_entry(dev, &bus->devices, bus_list)
1855		if (pci_is_bridge(dev) && pci_has_subordinate(dev))
1856				__pci_bus_size_bridges(dev->subordinate,
1857							 &add_list);
1858	up_read(&pci_bus_sem);
1859	__pci_bus_assign_resources(bus, &add_list, NULL);
1860	BUG_ON(!list_empty(&add_list));
1861}
1862EXPORT_SYMBOL_GPL(pci_assign_unassigned_bus_resources);
v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Support routines for initializing a PCI subsystem
   4 *
   5 * Extruded from code written by
   6 *      Dave Rusling (david.rusling@reo.mts.dec.com)
   7 *      David Mosberger (davidm@cs.arizona.edu)
   8 *	David Miller (davem@redhat.com)
   9 *
 
 
 
 
  10 * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
  11 *	     PCI-PCI bridges cleanup, sorted resource allocation.
  12 * Feb 2002, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
  13 *	     Converted to allocation in 3 passes, which gives
  14 *	     tighter packing. Prefetchable range support.
  15 */
  16
  17#include <linux/init.h>
  18#include <linux/kernel.h>
  19#include <linux/module.h>
  20#include <linux/pci.h>
  21#include <linux/errno.h>
  22#include <linux/ioport.h>
  23#include <linux/cache.h>
  24#include <linux/slab.h>
  25#include <linux/acpi.h>
  26#include "pci.h"
  27
  28unsigned int pci_flags;
  29
  30struct pci_dev_resource {
  31	struct list_head list;
  32	struct resource *res;
  33	struct pci_dev *dev;
  34	resource_size_t start;
  35	resource_size_t end;
  36	resource_size_t add_size;
  37	resource_size_t min_align;
  38	unsigned long flags;
  39};
  40
  41static void free_list(struct list_head *head)
  42{
  43	struct pci_dev_resource *dev_res, *tmp;
  44
  45	list_for_each_entry_safe(dev_res, tmp, head, list) {
  46		list_del(&dev_res->list);
  47		kfree(dev_res);
  48	}
  49}
  50
  51/**
  52 * add_to_list() - Add a new resource tracker to the list
  53 * @head:	Head of the list
  54 * @dev:	Device to which the resource belongs
  55 * @res:	Resource to be tracked
  56 * @add_size:	Additional size to be optionally added to the resource
 
 
  57 */
  58static int add_to_list(struct list_head *head, struct pci_dev *dev,
  59		       struct resource *res, resource_size_t add_size,
  60		       resource_size_t min_align)
  61{
  62	struct pci_dev_resource *tmp;
  63
  64	tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
  65	if (!tmp)
 
  66		return -ENOMEM;
 
  67
  68	tmp->res = res;
  69	tmp->dev = dev;
  70	tmp->start = res->start;
  71	tmp->end = res->end;
  72	tmp->flags = res->flags;
  73	tmp->add_size = add_size;
  74	tmp->min_align = min_align;
  75
  76	list_add(&tmp->list, head);
  77
  78	return 0;
  79}
  80
  81static void remove_from_list(struct list_head *head, struct resource *res)
 
  82{
  83	struct pci_dev_resource *dev_res, *tmp;
  84
  85	list_for_each_entry_safe(dev_res, tmp, head, list) {
  86		if (dev_res->res == res) {
  87			list_del(&dev_res->list);
  88			kfree(dev_res);
  89			break;
  90		}
  91	}
  92}
  93
  94static struct pci_dev_resource *res_to_dev_res(struct list_head *head,
  95					       struct resource *res)
  96{
  97	struct pci_dev_resource *dev_res;
  98
  99	list_for_each_entry(dev_res, head, list) {
 100		if (dev_res->res == res)
 
 
 
 
 
 
 
 
 101			return dev_res;
 
 102	}
 103
 104	return NULL;
 105}
 106
 107static resource_size_t get_res_add_size(struct list_head *head,
 108					struct resource *res)
 109{
 110	struct pci_dev_resource *dev_res;
 111
 112	dev_res = res_to_dev_res(head, res);
 113	return dev_res ? dev_res->add_size : 0;
 114}
 115
 116static resource_size_t get_res_add_align(struct list_head *head,
 117					 struct resource *res)
 118{
 119	struct pci_dev_resource *dev_res;
 120
 121	dev_res = res_to_dev_res(head, res);
 122	return dev_res ? dev_res->min_align : 0;
 123}
 124
 125
 126/* Sort resources by alignment */
 127static void pdev_sort_resources(struct pci_dev *dev, struct list_head *head)
 128{
 129	int i;
 130
 131	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
 132		struct resource *r;
 133		struct pci_dev_resource *dev_res, *tmp;
 134		resource_size_t r_align;
 135		struct list_head *n;
 136
 137		r = &dev->resource[i];
 138
 139		if (r->flags & IORESOURCE_PCI_FIXED)
 140			continue;
 141
 142		if (!(r->flags) || r->parent)
 143			continue;
 144
 145		r_align = pci_resource_alignment(dev, r);
 146		if (!r_align) {
 147			pci_warn(dev, "BAR %d: %pR has bogus alignment\n",
 148				 i, r);
 149			continue;
 150		}
 151
 152		tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
 153		if (!tmp)
 154			panic("pdev_sort_resources(): kmalloc() failed!\n");
 155		tmp->res = r;
 156		tmp->dev = dev;
 157
 158		/* Fallback is smallest one or list is empty */
 159		n = head;
 160		list_for_each_entry(dev_res, head, list) {
 161			resource_size_t align;
 162
 163			align = pci_resource_alignment(dev_res->dev,
 164							 dev_res->res);
 165
 166			if (r_align > align) {
 167				n = &dev_res->list;
 168				break;
 169			}
 170		}
 171		/* Insert it just before n */
 172		list_add_tail(&tmp->list, n);
 173	}
 174}
 175
 176static void __dev_sort_resources(struct pci_dev *dev, struct list_head *head)
 
 177{
 178	u16 class = dev->class >> 8;
 179
 180	/* Don't touch classless devices or host bridges or IOAPICs */
 181	if (class == PCI_CLASS_NOT_DEFINED || class == PCI_CLASS_BRIDGE_HOST)
 182		return;
 183
 184	/* Don't touch IOAPIC devices already enabled by firmware */
 185	if (class == PCI_CLASS_SYSTEM_PIC) {
 186		u16 command;
 187		pci_read_config_word(dev, PCI_COMMAND, &command);
 188		if (command & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY))
 189			return;
 190	}
 191
 192	pdev_sort_resources(dev, head);
 193}
 194
 195static inline void reset_resource(struct resource *res)
 196{
 197	res->start = 0;
 198	res->end = 0;
 199	res->flags = 0;
 200}
 201
 202/**
 203 * reassign_resources_sorted() - Satisfy any additional resource requests
 204 *
 205 * @realloc_head:	Head of the list tracking requests requiring
 206 *			additional resources
 207 * @head:		Head of the list tracking requests with allocated
 208 *			resources
 209 *
 210 * Walk through each element of the realloc_head and try to procure additional
 211 * resources for the element, provided the element is in the head list.
 
 212 */
 213static void reassign_resources_sorted(struct list_head *realloc_head,
 214				      struct list_head *head)
 215{
 216	struct resource *res;
 217	struct pci_dev_resource *add_res, *tmp;
 218	struct pci_dev_resource *dev_res;
 219	resource_size_t add_size, align;
 220	int idx;
 221
 222	list_for_each_entry_safe(add_res, tmp, realloc_head, list) {
 223		bool found_match = false;
 224
 225		res = add_res->res;
 226		/* Skip resource that has been reset */
 227		if (!res->flags)
 228			goto out;
 229
 230		/* Skip this resource if not found in head list */
 231		list_for_each_entry(dev_res, head, list) {
 232			if (dev_res->res == res) {
 233				found_match = true;
 234				break;
 235			}
 236		}
 237		if (!found_match) /* Just skip */
 238			continue;
 239
 240		idx = res - &add_res->dev->resource[0];
 241		add_size = add_res->add_size;
 242		align = add_res->min_align;
 243		if (!resource_size(res)) {
 244			res->start = align;
 245			res->end = res->start + add_size - 1;
 246			if (pci_assign_resource(add_res->dev, idx))
 247				reset_resource(res);
 248		} else {
 249			res->flags |= add_res->flags &
 250				 (IORESOURCE_STARTALIGN|IORESOURCE_SIZEALIGN);
 251			if (pci_reassign_resource(add_res->dev, idx,
 252						  add_size, align))
 253				pci_info(add_res->dev, "failed to add %llx res[%d]=%pR\n",
 254					 (unsigned long long) add_size, idx,
 255					 res);
 
 256		}
 257out:
 258		list_del(&add_res->list);
 259		kfree(add_res);
 260	}
 261}
 262
 263/**
 264 * assign_requested_resources_sorted() - Satisfy resource requests
 265 *
 266 * @head:	Head of the list tracking requests for resources
 267 * @fail_head:	Head of the list tracking requests that could not be
 268 *		allocated
 269 *
 270 * Satisfy resource requests of each element in the list.  Add requests that
 271 * could not be satisfied to the failed_list.
 272 */
 273static void assign_requested_resources_sorted(struct list_head *head,
 274				 struct list_head *fail_head)
 275{
 276	struct resource *res;
 277	struct pci_dev_resource *dev_res;
 278	int idx;
 279
 280	list_for_each_entry(dev_res, head, list) {
 281		res = dev_res->res;
 282		idx = res - &dev_res->dev->resource[0];
 283		if (resource_size(res) &&
 284		    pci_assign_resource(dev_res->dev, idx)) {
 285			if (fail_head) {
 286				/*
 287				 * If the failed resource is a ROM BAR and
 288				 * it will be enabled later, don't add it
 289				 * to the list.
 290				 */
 291				if (!((idx == PCI_ROM_RESOURCE) &&
 292				      (!(res->flags & IORESOURCE_ROM_ENABLE))))
 293					add_to_list(fail_head,
 294						    dev_res->dev, res,
 295						    0 /* don't care */,
 296						    0 /* don't care */);
 297			}
 298			reset_resource(res);
 299		}
 300	}
 301}
 302
 303static unsigned long pci_fail_res_type_mask(struct list_head *fail_head)
 304{
 305	struct pci_dev_resource *fail_res;
 306	unsigned long mask = 0;
 307
 308	/* Check failed type */
 309	list_for_each_entry(fail_res, fail_head, list)
 310		mask |= fail_res->flags;
 311
 312	/*
 313	 * One pref failed resource will set IORESOURCE_MEM, as we can
 314	 * allocate pref in non-pref range.  Will release all assigned
 315	 * non-pref sibling resources according to that bit.
 
 316	 */
 317	return mask & (IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH);
 318}
 319
 320static bool pci_need_to_release(unsigned long mask, struct resource *res)
 321{
 322	if (res->flags & IORESOURCE_IO)
 323		return !!(mask & IORESOURCE_IO);
 324
 325	/* Check pref at first */
 326	if (res->flags & IORESOURCE_PREFETCH) {
 327		if (mask & IORESOURCE_PREFETCH)
 328			return true;
 329		/* Count pref if its parent is non-pref */
 330		else if ((mask & IORESOURCE_MEM) &&
 331			 !(res->parent->flags & IORESOURCE_PREFETCH))
 332			return true;
 333		else
 334			return false;
 335	}
 336
 337	if (res->flags & IORESOURCE_MEM)
 338		return !!(mask & IORESOURCE_MEM);
 339
 340	return false;	/* Should not get here */
 341}
 342
 343static void __assign_resources_sorted(struct list_head *head,
 344				      struct list_head *realloc_head,
 345				      struct list_head *fail_head)
 346{
 347	/*
 348	 * Should not assign requested resources at first.  They could be
 349	 * adjacent, so later reassign can not reallocate them one by one in
 350	 * parent resource window.
 351	 *
 352	 * Try to assign requested + add_size at beginning.  If could do that,
 353	 * could get out early.  If could not do that, we still try to assign
 354	 * requested at first, then try to reassign add_size for some resources.
 355	 *
 356	 * Separate three resource type checking if we need to release
 357	 * assigned resource after requested + add_size try.
 358	 *
 359	 *	1. If IO port assignment fails, will release assigned IO
 360	 *	   port.
 361	 *	2. If pref MMIO assignment fails, release assigned pref
 362	 *	   MMIO.  If assigned pref MMIO's parent is non-pref MMIO
 363	 *	   and non-pref MMIO assignment fails, will release that
 364	 *	   assigned pref MMIO.
 365	 *	3. If non-pref MMIO assignment fails or pref MMIO
 366	 *	   assignment fails, will release assigned non-pref MMIO.
 367	 */
 368	LIST_HEAD(save_head);
 369	LIST_HEAD(local_fail_head);
 370	struct pci_dev_resource *save_res;
 371	struct pci_dev_resource *dev_res, *tmp_res, *dev_res2;
 372	unsigned long fail_type;
 373	resource_size_t add_align, align;
 374
 375	/* Check if optional add_size is there */
 376	if (!realloc_head || list_empty(realloc_head))
 377		goto requested_and_reassign;
 378
 379	/* Save original start, end, flags etc at first */
 380	list_for_each_entry(dev_res, head, list) {
 381		if (add_to_list(&save_head, dev_res->dev, dev_res->res, 0, 0)) {
 382			free_list(&save_head);
 383			goto requested_and_reassign;
 384		}
 385	}
 386
 387	/* Update res in head list with add_size in realloc_head list */
 388	list_for_each_entry_safe(dev_res, tmp_res, head, list) {
 389		dev_res->res->end += get_res_add_size(realloc_head,
 390							dev_res->res);
 391
 392		/*
 393		 * There are two kinds of additional resources in the list:
 394		 * 1. bridge resource  -- IORESOURCE_STARTALIGN
 395		 * 2. SR-IOV resource  -- IORESOURCE_SIZEALIGN
 396		 * Here just fix the additional alignment for bridge
 397		 */
 398		if (!(dev_res->res->flags & IORESOURCE_STARTALIGN))
 399			continue;
 400
 401		add_align = get_res_add_align(realloc_head, dev_res->res);
 402
 403		/*
 404		 * The "head" list is sorted by alignment so resources with
 405		 * bigger alignment will be assigned first.  After we
 406		 * change the alignment of a dev_res in "head" list, we
 407		 * need to reorder the list by alignment to make it
 408		 * consistent.
 409		 */
 410		if (add_align > dev_res->res->start) {
 411			resource_size_t r_size = resource_size(dev_res->res);
 412
 413			dev_res->res->start = add_align;
 414			dev_res->res->end = add_align + r_size - 1;
 415
 416			list_for_each_entry(dev_res2, head, list) {
 417				align = pci_resource_alignment(dev_res2->dev,
 418							       dev_res2->res);
 419				if (add_align > align) {
 420					list_move_tail(&dev_res->list,
 421						       &dev_res2->list);
 422					break;
 423				}
 424			}
 425		}
 426
 427	}
 428
 429	/* Try updated head list with add_size added */
 430	assign_requested_resources_sorted(head, &local_fail_head);
 431
 432	/* All assigned with add_size? */
 433	if (list_empty(&local_fail_head)) {
 434		/* Remove head list from realloc_head list */
 435		list_for_each_entry(dev_res, head, list)
 436			remove_from_list(realloc_head, dev_res->res);
 437		free_list(&save_head);
 438		free_list(head);
 439		return;
 440	}
 441
 442	/* Check failed type */
 443	fail_type = pci_fail_res_type_mask(&local_fail_head);
 444	/* Remove not need to be released assigned res from head list etc */
 445	list_for_each_entry_safe(dev_res, tmp_res, head, list)
 446		if (dev_res->res->parent &&
 447		    !pci_need_to_release(fail_type, dev_res->res)) {
 448			/* Remove it from realloc_head list */
 449			remove_from_list(realloc_head, dev_res->res);
 450			remove_from_list(&save_head, dev_res->res);
 451			list_del(&dev_res->list);
 452			kfree(dev_res);
 453		}
 454
 455	free_list(&local_fail_head);
 456	/* Release assigned resource */
 457	list_for_each_entry(dev_res, head, list)
 458		if (dev_res->res->parent)
 459			release_resource(dev_res->res);
 460	/* Restore start/end/flags from saved list */
 461	list_for_each_entry(save_res, &save_head, list) {
 462		struct resource *res = save_res->res;
 463
 464		res->start = save_res->start;
 465		res->end = save_res->end;
 466		res->flags = save_res->flags;
 467	}
 468	free_list(&save_head);
 469
 470requested_and_reassign:
 471	/* Satisfy the must-have resource requests */
 472	assign_requested_resources_sorted(head, fail_head);
 473
 474	/* Try to satisfy any additional optional resource requests */
 
 475	if (realloc_head)
 476		reassign_resources_sorted(realloc_head, head);
 477	free_list(head);
 478}
 479
 480static void pdev_assign_resources_sorted(struct pci_dev *dev,
 481					 struct list_head *add_head,
 482					 struct list_head *fail_head)
 483{
 484	LIST_HEAD(head);
 485
 486	__dev_sort_resources(dev, &head);
 487	__assign_resources_sorted(&head, add_head, fail_head);
 488
 489}
 490
 491static void pbus_assign_resources_sorted(const struct pci_bus *bus,
 492					 struct list_head *realloc_head,
 493					 struct list_head *fail_head)
 494{
 495	struct pci_dev *dev;
 496	LIST_HEAD(head);
 497
 498	list_for_each_entry(dev, &bus->devices, bus_list)
 499		__dev_sort_resources(dev, &head);
 500
 501	__assign_resources_sorted(&head, realloc_head, fail_head);
 502}
 503
 504void pci_setup_cardbus(struct pci_bus *bus)
 505{
 506	struct pci_dev *bridge = bus->self;
 507	struct resource *res;
 508	struct pci_bus_region region;
 509
 510	pci_info(bridge, "CardBus bridge to %pR\n",
 511		 &bus->busn_res);
 512
 513	res = bus->resource[0];
 514	pcibios_resource_to_bus(bridge->bus, &region, res);
 515	if (res->flags & IORESOURCE_IO) {
 516		/*
 517		 * The IO resource is allocated a range twice as large as it
 518		 * would normally need.  This allows us to set both IO regs.
 519		 */
 520		pci_info(bridge, "  bridge window %pR\n", res);
 521		pci_write_config_dword(bridge, PCI_CB_IO_BASE_0,
 522					region.start);
 523		pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_0,
 524					region.end);
 525	}
 526
 527	res = bus->resource[1];
 528	pcibios_resource_to_bus(bridge->bus, &region, res);
 529	if (res->flags & IORESOURCE_IO) {
 530		pci_info(bridge, "  bridge window %pR\n", res);
 531		pci_write_config_dword(bridge, PCI_CB_IO_BASE_1,
 532					region.start);
 533		pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_1,
 534					region.end);
 535	}
 536
 537	res = bus->resource[2];
 538	pcibios_resource_to_bus(bridge->bus, &region, res);
 539	if (res->flags & IORESOURCE_MEM) {
 540		pci_info(bridge, "  bridge window %pR\n", res);
 541		pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_0,
 542					region.start);
 543		pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_0,
 544					region.end);
 545	}
 546
 547	res = bus->resource[3];
 548	pcibios_resource_to_bus(bridge->bus, &region, res);
 549	if (res->flags & IORESOURCE_MEM) {
 550		pci_info(bridge, "  bridge window %pR\n", res);
 551		pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_1,
 552					region.start);
 553		pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_1,
 554					region.end);
 555	}
 556}
 557EXPORT_SYMBOL(pci_setup_cardbus);
 558
 559/*
 560 * Initialize bridges with base/limit values we have collected.  PCI-to-PCI
 561 * Bridge Architecture Specification rev. 1.1 (1998) requires that if there
 562 * are no I/O ports or memory behind the bridge, the corresponding range
 563 * must be turned off by writing base value greater than limit to the
 564 * bridge's base/limit registers.
 565 *
 566 * Note: care must be taken when updating I/O base/limit registers of
 567 * bridges which support 32-bit I/O.  This update requires two config space
 568 * writes, so it's quite possible that an I/O window of the bridge will
 569 * have some undesirable address (e.g. 0) after the first write.  Ditto
 570 * 64-bit prefetchable MMIO.
 571 */
 572static void pci_setup_bridge_io(struct pci_dev *bridge)
 573{
 574	struct resource *res;
 575	struct pci_bus_region region;
 576	unsigned long io_mask;
 577	u8 io_base_lo, io_limit_lo;
 578	u16 l;
 579	u32 io_upper16;
 580
 581	io_mask = PCI_IO_RANGE_MASK;
 582	if (bridge->io_window_1k)
 583		io_mask = PCI_IO_1K_RANGE_MASK;
 584
 585	/* Set up the top and bottom of the PCI I/O segment for this bus */
 586	res = &bridge->resource[PCI_BRIDGE_RESOURCES + 0];
 587	pcibios_resource_to_bus(bridge->bus, &region, res);
 588	if (res->flags & IORESOURCE_IO) {
 589		pci_read_config_word(bridge, PCI_IO_BASE, &l);
 590		io_base_lo = (region.start >> 8) & io_mask;
 591		io_limit_lo = (region.end >> 8) & io_mask;
 592		l = ((u16) io_limit_lo << 8) | io_base_lo;
 593		/* Set up upper 16 bits of I/O base/limit */
 594		io_upper16 = (region.end & 0xffff0000) | (region.start >> 16);
 595		pci_info(bridge, "  bridge window %pR\n", res);
 596	} else {
 597		/* Clear upper 16 bits of I/O base/limit */
 598		io_upper16 = 0;
 599		l = 0x00f0;
 600	}
 601	/* Temporarily disable the I/O range before updating PCI_IO_BASE */
 602	pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, 0x0000ffff);
 603	/* Update lower 16 bits of I/O base/limit */
 604	pci_write_config_word(bridge, PCI_IO_BASE, l);
 605	/* Update upper 16 bits of I/O base/limit */
 606	pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, io_upper16);
 607}
 608
 609static void pci_setup_bridge_mmio(struct pci_dev *bridge)
 610{
 611	struct resource *res;
 612	struct pci_bus_region region;
 613	u32 l;
 614
 615	/* Set up the top and bottom of the PCI Memory segment for this bus */
 616	res = &bridge->resource[PCI_BRIDGE_RESOURCES + 1];
 617	pcibios_resource_to_bus(bridge->bus, &region, res);
 618	if (res->flags & IORESOURCE_MEM) {
 619		l = (region.start >> 16) & 0xfff0;
 620		l |= region.end & 0xfff00000;
 621		pci_info(bridge, "  bridge window %pR\n", res);
 622	} else {
 623		l = 0x0000fff0;
 624	}
 625	pci_write_config_dword(bridge, PCI_MEMORY_BASE, l);
 626}
 627
 628static void pci_setup_bridge_mmio_pref(struct pci_dev *bridge)
 629{
 630	struct resource *res;
 631	struct pci_bus_region region;
 632	u32 l, bu, lu;
 633
 634	/*
 635	 * Clear out the upper 32 bits of PREF limit.  If
 636	 * PCI_PREF_BASE_UPPER32 was non-zero, this temporarily disables
 637	 * PREF range, which is ok.
 638	 */
 639	pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, 0);
 640
 641	/* Set up PREF base/limit */
 642	bu = lu = 0;
 643	res = &bridge->resource[PCI_BRIDGE_RESOURCES + 2];
 644	pcibios_resource_to_bus(bridge->bus, &region, res);
 645	if (res->flags & IORESOURCE_PREFETCH) {
 646		l = (region.start >> 16) & 0xfff0;
 647		l |= region.end & 0xfff00000;
 648		if (res->flags & IORESOURCE_MEM_64) {
 649			bu = upper_32_bits(region.start);
 650			lu = upper_32_bits(region.end);
 651		}
 652		pci_info(bridge, "  bridge window %pR\n", res);
 653	} else {
 654		l = 0x0000fff0;
 655	}
 656	pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l);
 657
 658	/* Set the upper 32 bits of PREF base & limit */
 659	pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, bu);
 660	pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, lu);
 661}
 662
 663static void __pci_setup_bridge(struct pci_bus *bus, unsigned long type)
 664{
 665	struct pci_dev *bridge = bus->self;
 666
 667	pci_info(bridge, "PCI bridge to %pR\n",
 668		 &bus->busn_res);
 669
 670	if (type & IORESOURCE_IO)
 671		pci_setup_bridge_io(bridge);
 672
 673	if (type & IORESOURCE_MEM)
 674		pci_setup_bridge_mmio(bridge);
 675
 676	if (type & IORESOURCE_PREFETCH)
 677		pci_setup_bridge_mmio_pref(bridge);
 678
 679	pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, bus->bridge_ctl);
 680}
 681
 682void __weak pcibios_setup_bridge(struct pci_bus *bus, unsigned long type)
 683{
 684}
 685
 686void pci_setup_bridge(struct pci_bus *bus)
 687{
 688	unsigned long type = IORESOURCE_IO | IORESOURCE_MEM |
 689				  IORESOURCE_PREFETCH;
 690
 691	pcibios_setup_bridge(bus, type);
 692	__pci_setup_bridge(bus, type);
 693}
 694
 695
 696int pci_claim_bridge_resource(struct pci_dev *bridge, int i)
 697{
 698	if (i < PCI_BRIDGE_RESOURCES || i > PCI_BRIDGE_RESOURCE_END)
 699		return 0;
 700
 701	if (pci_claim_resource(bridge, i) == 0)
 702		return 0;	/* Claimed the window */
 703
 704	if ((bridge->class >> 8) != PCI_CLASS_BRIDGE_PCI)
 705		return 0;
 706
 707	if (!pci_bus_clip_resource(bridge, i))
 708		return -EINVAL;	/* Clipping didn't change anything */
 709
 710	switch (i - PCI_BRIDGE_RESOURCES) {
 711	case 0:
 712		pci_setup_bridge_io(bridge);
 713		break;
 714	case 1:
 715		pci_setup_bridge_mmio(bridge);
 716		break;
 717	case 2:
 718		pci_setup_bridge_mmio_pref(bridge);
 719		break;
 720	default:
 721		return -EINVAL;
 722	}
 723
 724	if (pci_claim_resource(bridge, i) == 0)
 725		return 0;	/* Claimed a smaller window */
 726
 727	return -EINVAL;
 728}
 729
 730/*
 731 * Check whether the bridge supports optional I/O and prefetchable memory
 732 * ranges.  If not, the respective base/limit registers must be read-only
 733 * and read as 0.
 734 */
 735static void pci_bridge_check_ranges(struct pci_bus *bus)
 736{
 
 
 737	struct pci_dev *bridge = bus->self;
 738	struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
 739
 
 740	b_res[1].flags |= IORESOURCE_MEM;
 741
 742	if (bridge->io_window)
 
 
 
 
 
 
 743		b_res[0].flags |= IORESOURCE_IO;
 744
 745	if (bridge->pref_window) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 746		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
 747		if (bridge->pref_64_window) {
 
 748			b_res[2].flags |= IORESOURCE_MEM_64;
 749			b_res[2].flags |= PCI_PREF_RANGE_TYPE_64;
 750		}
 751	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 752}
 753
 754/*
 755 * Helper function for sizing routines: find first available bus resource
 756 * of a given type.  Note: we intentionally skip the bus resources which
 757 * have already been assigned (that is, have non-NULL parent resource).
 758 */
 759static struct resource *find_free_bus_resource(struct pci_bus *bus,
 760					       unsigned long type_mask,
 761					       unsigned long type)
 762{
 763	int i;
 764	struct resource *r;
 765
 766	pci_bus_for_each_resource(bus, r, i) {
 767		if (r == &ioport_resource || r == &iomem_resource)
 768			continue;
 769		if (r && (r->flags & type_mask) == type && !r->parent)
 770			return r;
 771	}
 772	return NULL;
 773}
 774
 775static resource_size_t calculate_iosize(resource_size_t size,
 776					resource_size_t min_size,
 777					resource_size_t size1,
 778					resource_size_t add_size,
 779					resource_size_t children_add_size,
 780					resource_size_t old_size,
 781					resource_size_t align)
 782{
 783	if (size < min_size)
 784		size = min_size;
 785	if (old_size == 1)
 786		old_size = 0;
 787	/*
 788	 * To be fixed in 2.5: we should have sort of HAVE_ISA flag in the
 789	 * struct pci_bus.
 790	 */
 791#if defined(CONFIG_ISA) || defined(CONFIG_EISA)
 792	size = (size & 0xff) + ((size & ~0xffUL) << 2);
 793#endif
 794	size = size + size1;
 795	if (size < old_size)
 796		size = old_size;
 797
 798	size = ALIGN(max(size, add_size) + children_add_size, align);
 799	return size;
 800}
 801
 802static resource_size_t calculate_memsize(resource_size_t size,
 803					 resource_size_t min_size,
 804					 resource_size_t add_size,
 805					 resource_size_t children_add_size,
 806					 resource_size_t old_size,
 807					 resource_size_t align)
 808{
 809	if (size < min_size)
 810		size = min_size;
 811	if (old_size == 1)
 812		old_size = 0;
 813	if (size < old_size)
 814		size = old_size;
 815
 816	size = ALIGN(max(size, add_size) + children_add_size, align);
 817	return size;
 818}
 819
 820resource_size_t __weak pcibios_window_alignment(struct pci_bus *bus,
 821						unsigned long type)
 822{
 823	return 1;
 824}
 825
 826#define PCI_P2P_DEFAULT_MEM_ALIGN	0x100000	/* 1MiB */
 827#define PCI_P2P_DEFAULT_IO_ALIGN	0x1000		/* 4KiB */
 828#define PCI_P2P_DEFAULT_IO_ALIGN_1K	0x400		/* 1KiB */
 829
 830static resource_size_t window_alignment(struct pci_bus *bus, unsigned long type)
 
 831{
 832	resource_size_t align = 1, arch_align;
 833
 834	if (type & IORESOURCE_MEM)
 835		align = PCI_P2P_DEFAULT_MEM_ALIGN;
 836	else if (type & IORESOURCE_IO) {
 837		/*
 838		 * Per spec, I/O windows are 4K-aligned, but some bridges have
 839		 * an extension to support 1K alignment.
 840		 */
 841		if (bus->self->io_window_1k)
 842			align = PCI_P2P_DEFAULT_IO_ALIGN_1K;
 843		else
 844			align = PCI_P2P_DEFAULT_IO_ALIGN;
 845	}
 846
 847	arch_align = pcibios_window_alignment(bus, type);
 848	return max(align, arch_align);
 849}
 850
 851/**
 852 * pbus_size_io() - Size the I/O window of a given bus
 853 *
 854 * @bus:		The bus
 855 * @min_size:		The minimum I/O window that must be allocated
 856 * @add_size:		Additional optional I/O window
 857 * @realloc_head:	Track the additional I/O window on this list
 858 *
 859 * Sizing the I/O windows of the PCI-PCI bridge is trivial, since these
 860 * windows have 1K or 4K granularity and the I/O ranges of non-bridge PCI
 861 * devices are limited to 256 bytes.  We must be careful with the ISA
 862 * aliasing though.
 863 */
 864static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
 865			 resource_size_t add_size,
 866			 struct list_head *realloc_head)
 867{
 868	struct pci_dev *dev;
 869	struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO,
 870							IORESOURCE_IO);
 871	resource_size_t size = 0, size0 = 0, size1 = 0;
 872	resource_size_t children_add_size = 0;
 873	resource_size_t min_align, align;
 874
 875	if (!b_res)
 876		return;
 877
 878	min_align = window_alignment(bus, IORESOURCE_IO);
 879	list_for_each_entry(dev, &bus->devices, bus_list) {
 880		int i;
 881
 882		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
 883			struct resource *r = &dev->resource[i];
 884			unsigned long r_size;
 885
 886			if (r->parent || !(r->flags & IORESOURCE_IO))
 887				continue;
 888			r_size = resource_size(r);
 889
 890			if (r_size < 0x400)
 891				/* Might be re-aligned for ISA */
 892				size += r_size;
 893			else
 894				size1 += r_size;
 895
 896			align = pci_resource_alignment(dev, r);
 897			if (align > min_align)
 898				min_align = align;
 899
 900			if (realloc_head)
 901				children_add_size += get_res_add_size(realloc_head, r);
 902		}
 903	}
 904
 905	size0 = calculate_iosize(size, min_size, size1, 0, 0,
 906			resource_size(b_res), min_align);
 907	size1 = (!realloc_head || (realloc_head && !add_size && !children_add_size)) ? size0 :
 908		calculate_iosize(size, min_size, size1, add_size, children_add_size,
 
 
 909			resource_size(b_res), min_align);
 910	if (!size0 && !size1) {
 911		if (b_res->start || b_res->end)
 912			pci_info(bus->self, "disabling bridge window %pR to %pR (unused)\n",
 913				 b_res, &bus->busn_res);
 914		b_res->flags = 0;
 915		return;
 916	}
 917
 918	b_res->start = min_align;
 919	b_res->end = b_res->start + size0 - 1;
 920	b_res->flags |= IORESOURCE_STARTALIGN;
 921	if (size1 > size0 && realloc_head) {
 922		add_to_list(realloc_head, bus->self, b_res, size1-size0,
 923			    min_align);
 924		pci_info(bus->self, "bridge window %pR to %pR add_size %llx\n",
 925			 b_res, &bus->busn_res,
 926			 (unsigned long long) size1 - size0);
 927	}
 928}
 929
 930static inline resource_size_t calculate_mem_align(resource_size_t *aligns,
 931						  int max_order)
 932{
 933	resource_size_t align = 0;
 934	resource_size_t min_align = 0;
 935	int order;
 936
 937	for (order = 0; order <= max_order; order++) {
 938		resource_size_t align1 = 1;
 939
 940		align1 <<= (order + 20);
 941
 942		if (!align)
 943			min_align = align1;
 944		else if (ALIGN(align + min_align, min_align) < align1)
 945			min_align = align1 >> 1;
 946		align += aligns[order];
 947	}
 948
 949	return min_align;
 950}
 951
 952/**
 953 * pbus_size_mem() - Size the memory window of a given bus
 954 *
 955 * @bus:		The bus
 956 * @mask:		Mask the resource flag, then compare it with type
 957 * @type:		The type of free resource from bridge
 958 * @type2:		Second match type
 959 * @type3:		Third match type
 960 * @min_size:		The minimum memory window that must be allocated
 961 * @add_size:		Additional optional memory window
 962 * @realloc_head:	Track the additional memory window on this list
 963 *
 964 * Calculate the size of the bus and minimal alignment which guarantees
 965 * that all child resources fit in this size.
 966 *
 967 * Return -ENOSPC if there's no available bus resource of the desired
 968 * type.  Otherwise, set the bus resource start/end to indicate the
 969 * required size, add things to realloc_head (if supplied), and return 0.
 970 */
 971static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
 972			 unsigned long type, unsigned long type2,
 973			 unsigned long type3, resource_size_t min_size,
 974			 resource_size_t add_size,
 975			 struct list_head *realloc_head)
 976{
 977	struct pci_dev *dev;
 978	resource_size_t min_align, align, size, size0, size1;
 979	resource_size_t aligns[18]; /* Alignments from 1MB to 128GB */
 980	int order, max_order;
 981	struct resource *b_res = find_free_bus_resource(bus,
 982					mask | IORESOURCE_PREFETCH, type);
 983	resource_size_t children_add_size = 0;
 984	resource_size_t children_add_align = 0;
 985	resource_size_t add_align = 0;
 986
 987	if (!b_res)
 988		return -ENOSPC;
 989
 990	memset(aligns, 0, sizeof(aligns));
 991	max_order = 0;
 992	size = 0;
 993
 994	list_for_each_entry(dev, &bus->devices, bus_list) {
 995		int i;
 996
 997		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
 998			struct resource *r = &dev->resource[i];
 999			resource_size_t r_size;
1000
1001			if (r->parent || (r->flags & IORESOURCE_PCI_FIXED) ||
1002			    ((r->flags & mask) != type &&
1003			     (r->flags & mask) != type2 &&
1004			     (r->flags & mask) != type3))
1005				continue;
1006			r_size = resource_size(r);
1007#ifdef CONFIG_PCI_IOV
1008			/* Put SRIOV requested res to the optional list */
1009			if (realloc_head && i >= PCI_IOV_RESOURCES &&
1010					i <= PCI_IOV_RESOURCE_END) {
1011				add_align = max(pci_resource_alignment(dev, r), add_align);
1012				r->end = r->start - 1;
1013				add_to_list(realloc_head, dev, r, r_size, 0 /* Don't care */);
1014				children_add_size += r_size;
1015				continue;
1016			}
1017#endif
1018			/*
1019			 * aligns[0] is for 1MB (since bridge memory
1020			 * windows are always at least 1MB aligned), so
1021			 * keep "order" from being negative for smaller
1022			 * resources.
1023			 */
1024			align = pci_resource_alignment(dev, r);
1025			order = __ffs(align) - 20;
1026			if (order < 0)
1027				order = 0;
1028			if (order >= ARRAY_SIZE(aligns)) {
1029				pci_warn(dev, "disabling BAR %d: %pR (bad alignment %#llx)\n",
1030					 i, r, (unsigned long long) align);
1031				r->flags = 0;
1032				continue;
1033			}
1034			size += max(r_size, align);
1035			/*
1036			 * Exclude ranges with size > align from calculation of
1037			 * the alignment.
1038			 */
1039			if (r_size <= align)
1040				aligns[order] += align;
1041			if (order > max_order)
1042				max_order = order;
1043
1044			if (realloc_head) {
1045				children_add_size += get_res_add_size(realloc_head, r);
1046				children_add_align = get_res_add_align(realloc_head, r);
1047				add_align = max(add_align, children_add_align);
1048			}
1049		}
1050	}
1051
1052	min_align = calculate_mem_align(aligns, max_order);
1053	min_align = max(min_align, window_alignment(bus, b_res->flags));
1054	size0 = calculate_memsize(size, min_size, 0, 0, resource_size(b_res), min_align);
1055	add_align = max(min_align, add_align);
1056	size1 = (!realloc_head || (realloc_head && !add_size && !children_add_size)) ? size0 :
1057		calculate_memsize(size, min_size, add_size, children_add_size,
 
 
1058				resource_size(b_res), add_align);
1059	if (!size0 && !size1) {
1060		if (b_res->start || b_res->end)
1061			pci_info(bus->self, "disabling bridge window %pR to %pR (unused)\n",
1062				 b_res, &bus->busn_res);
1063		b_res->flags = 0;
1064		return 0;
1065	}
1066	b_res->start = min_align;
1067	b_res->end = size0 + min_align - 1;
1068	b_res->flags |= IORESOURCE_STARTALIGN;
1069	if (size1 > size0 && realloc_head) {
1070		add_to_list(realloc_head, bus->self, b_res, size1-size0, add_align);
1071		pci_info(bus->self, "bridge window %pR to %pR add_size %llx add_align %llx\n",
1072			   b_res, &bus->busn_res,
1073			   (unsigned long long) (size1 - size0),
1074			   (unsigned long long) add_align);
1075	}
1076	return 0;
1077}
1078
1079unsigned long pci_cardbus_resource_alignment(struct resource *res)
1080{
1081	if (res->flags & IORESOURCE_IO)
1082		return pci_cardbus_io_size;
1083	if (res->flags & IORESOURCE_MEM)
1084		return pci_cardbus_mem_size;
1085	return 0;
1086}
1087
1088static void pci_bus_size_cardbus(struct pci_bus *bus,
1089				 struct list_head *realloc_head)
1090{
1091	struct pci_dev *bridge = bus->self;
1092	struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
1093	resource_size_t b_res_3_size = pci_cardbus_mem_size * 2;
1094	u16 ctrl;
1095
1096	if (b_res[0].parent)
1097		goto handle_b_res_1;
1098	/*
1099	 * Reserve some resources for CardBus.  We reserve a fixed amount
1100	 * of bus space for CardBus bridges.
1101	 */
1102	b_res[0].start = pci_cardbus_io_size;
1103	b_res[0].end = b_res[0].start + pci_cardbus_io_size - 1;
1104	b_res[0].flags |= IORESOURCE_IO | IORESOURCE_STARTALIGN;
1105	if (realloc_head) {
1106		b_res[0].end -= pci_cardbus_io_size;
1107		add_to_list(realloc_head, bridge, b_res, pci_cardbus_io_size,
1108				pci_cardbus_io_size);
1109	}
1110
1111handle_b_res_1:
1112	if (b_res[1].parent)
1113		goto handle_b_res_2;
1114	b_res[1].start = pci_cardbus_io_size;
1115	b_res[1].end = b_res[1].start + pci_cardbus_io_size - 1;
1116	b_res[1].flags |= IORESOURCE_IO | IORESOURCE_STARTALIGN;
1117	if (realloc_head) {
1118		b_res[1].end -= pci_cardbus_io_size;
1119		add_to_list(realloc_head, bridge, b_res+1, pci_cardbus_io_size,
1120				 pci_cardbus_io_size);
1121	}
1122
1123handle_b_res_2:
1124	/* MEM1 must not be pref MMIO */
1125	pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
1126	if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM1) {
1127		ctrl &= ~PCI_CB_BRIDGE_CTL_PREFETCH_MEM1;
1128		pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
1129		pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
1130	}
1131
1132	/* Check whether prefetchable memory is supported by this bridge. */
 
 
 
1133	pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
1134	if (!(ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0)) {
1135		ctrl |= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0;
1136		pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
1137		pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
1138	}
1139
1140	if (b_res[2].parent)
1141		goto handle_b_res_3;
1142	/*
1143	 * If we have prefetchable memory support, allocate two regions.
1144	 * Otherwise, allocate one region of twice the size.
 
1145	 */
1146	if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) {
1147		b_res[2].start = pci_cardbus_mem_size;
1148		b_res[2].end = b_res[2].start + pci_cardbus_mem_size - 1;
1149		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH |
1150				  IORESOURCE_STARTALIGN;
1151		if (realloc_head) {
1152			b_res[2].end -= pci_cardbus_mem_size;
1153			add_to_list(realloc_head, bridge, b_res+2,
1154				 pci_cardbus_mem_size, pci_cardbus_mem_size);
1155		}
1156
1157		/* Reduce that to half */
1158		b_res_3_size = pci_cardbus_mem_size;
1159	}
1160
1161handle_b_res_3:
1162	if (b_res[3].parent)
1163		goto handle_done;
1164	b_res[3].start = pci_cardbus_mem_size;
1165	b_res[3].end = b_res[3].start + b_res_3_size - 1;
1166	b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_STARTALIGN;
1167	if (realloc_head) {
1168		b_res[3].end -= b_res_3_size;
1169		add_to_list(realloc_head, bridge, b_res+3, b_res_3_size,
1170				 pci_cardbus_mem_size);
1171	}
1172
1173handle_done:
1174	;
1175}
1176
1177void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)
1178{
1179	struct pci_dev *dev;
1180	unsigned long mask, prefmask, type2 = 0, type3 = 0;
1181	resource_size_t additional_mem_size = 0, additional_io_size = 0;
1182	struct resource *b_res;
1183	int ret;
1184
1185	list_for_each_entry(dev, &bus->devices, bus_list) {
1186		struct pci_bus *b = dev->subordinate;
1187		if (!b)
1188			continue;
1189
1190		switch (dev->hdr_type) {
1191		case PCI_HEADER_TYPE_CARDBUS:
1192			pci_bus_size_cardbus(b, realloc_head);
1193			break;
1194
1195		case PCI_HEADER_TYPE_BRIDGE:
1196		default:
1197			__pci_bus_size_bridges(b, realloc_head);
1198			break;
1199		}
1200	}
1201
1202	/* The root bus? */
1203	if (pci_is_root_bus(bus))
1204		return;
1205
1206	switch (bus->self->hdr_type) {
1207	case PCI_HEADER_TYPE_CARDBUS:
1208		/* Don't size CardBuses yet */
1209		break;
1210
1211	case PCI_HEADER_TYPE_BRIDGE:
1212		pci_bridge_check_ranges(bus);
1213		if (bus->self->is_hotplug_bridge) {
1214			additional_io_size  = pci_hotplug_io_size;
1215			additional_mem_size = pci_hotplug_mem_size;
1216		}
1217		/* Fall through */
1218	default:
1219		pbus_size_io(bus, realloc_head ? 0 : additional_io_size,
1220			     additional_io_size, realloc_head);
1221
1222		/*
1223		 * If there's a 64-bit prefetchable MMIO window, compute
1224		 * the size required to put all 64-bit prefetchable
1225		 * resources in it.
1226		 */
1227		b_res = &bus->self->resource[PCI_BRIDGE_RESOURCES];
1228		mask = IORESOURCE_MEM;
1229		prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH;
1230		if (b_res[2].flags & IORESOURCE_MEM_64) {
1231			prefmask |= IORESOURCE_MEM_64;
1232			ret = pbus_size_mem(bus, prefmask, prefmask,
1233				  prefmask, prefmask,
1234				  realloc_head ? 0 : additional_mem_size,
1235				  additional_mem_size, realloc_head);
1236
1237			/*
1238			 * If successful, all non-prefetchable resources
1239			 * and any 32-bit prefetchable resources will go in
1240			 * the non-prefetchable window.
1241			 */
1242			if (ret == 0) {
1243				mask = prefmask;
1244				type2 = prefmask & ~IORESOURCE_MEM_64;
1245				type3 = prefmask & ~IORESOURCE_PREFETCH;
1246			}
1247		}
1248
1249		/*
1250		 * If there is no 64-bit prefetchable window, compute the
1251		 * size required to put all prefetchable resources in the
1252		 * 32-bit prefetchable window (if there is one).
1253		 */
1254		if (!type2) {
1255			prefmask &= ~IORESOURCE_MEM_64;
1256			ret = pbus_size_mem(bus, prefmask, prefmask,
1257					 prefmask, prefmask,
1258					 realloc_head ? 0 : additional_mem_size,
1259					 additional_mem_size, realloc_head);
1260
1261			/*
1262			 * If successful, only non-prefetchable resources
1263			 * will go in the non-prefetchable window.
1264			 */
1265			if (ret == 0)
1266				mask = prefmask;
1267			else
1268				additional_mem_size += additional_mem_size;
1269
1270			type2 = type3 = IORESOURCE_MEM;
1271		}
1272
1273		/*
1274		 * Compute the size required to put everything else in the
1275		 * non-prefetchable window. This includes:
1276		 *
1277		 *   - all non-prefetchable resources
1278		 *   - 32-bit prefetchable resources if there's a 64-bit
1279		 *     prefetchable window or no prefetchable window at all
1280		 *   - 64-bit prefetchable resources if there's no prefetchable
1281		 *     window at all
1282		 *
1283		 * Note that the strategy in __pci_assign_resource() must match
1284		 * that used here. Specifically, we cannot put a 32-bit
1285		 * prefetchable resource in a 64-bit prefetchable window.
 
1286		 */
1287		pbus_size_mem(bus, mask, IORESOURCE_MEM, type2, type3,
1288				realloc_head ? 0 : additional_mem_size,
1289				additional_mem_size, realloc_head);
1290		break;
1291	}
1292}
1293
1294void pci_bus_size_bridges(struct pci_bus *bus)
1295{
1296	__pci_bus_size_bridges(bus, NULL);
1297}
1298EXPORT_SYMBOL(pci_bus_size_bridges);
1299
1300static void assign_fixed_resource_on_bus(struct pci_bus *b, struct resource *r)
1301{
1302	int i;
1303	struct resource *parent_r;
1304	unsigned long mask = IORESOURCE_IO | IORESOURCE_MEM |
1305			     IORESOURCE_PREFETCH;
1306
1307	pci_bus_for_each_resource(b, parent_r, i) {
1308		if (!parent_r)
1309			continue;
1310
1311		if ((r->flags & mask) == (parent_r->flags & mask) &&
1312		    resource_contains(parent_r, r))
1313			request_resource(parent_r, r);
1314	}
1315}
1316
1317/*
1318 * Try to assign any resources marked as IORESOURCE_PCI_FIXED, as they are
1319 * skipped by pbus_assign_resources_sorted().
1320 */
1321static void pdev_assign_fixed_resources(struct pci_dev *dev)
1322{
1323	int i;
1324
1325	for (i = 0; i <  PCI_NUM_RESOURCES; i++) {
1326		struct pci_bus *b;
1327		struct resource *r = &dev->resource[i];
1328
1329		if (r->parent || !(r->flags & IORESOURCE_PCI_FIXED) ||
1330		    !(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
1331			continue;
1332
1333		b = dev->bus;
1334		while (b && !r->parent) {
1335			assign_fixed_resource_on_bus(b, r);
1336			b = b->parent;
1337		}
1338	}
1339}
1340
1341void __pci_bus_assign_resources(const struct pci_bus *bus,
1342				struct list_head *realloc_head,
1343				struct list_head *fail_head)
1344{
1345	struct pci_bus *b;
1346	struct pci_dev *dev;
1347
1348	pbus_assign_resources_sorted(bus, realloc_head, fail_head);
1349
1350	list_for_each_entry(dev, &bus->devices, bus_list) {
1351		pdev_assign_fixed_resources(dev);
1352
1353		b = dev->subordinate;
1354		if (!b)
1355			continue;
1356
1357		__pci_bus_assign_resources(b, realloc_head, fail_head);
1358
1359		switch (dev->hdr_type) {
1360		case PCI_HEADER_TYPE_BRIDGE:
1361			if (!pci_is_enabled(dev))
1362				pci_setup_bridge(b);
1363			break;
1364
1365		case PCI_HEADER_TYPE_CARDBUS:
1366			pci_setup_cardbus(b);
1367			break;
1368
1369		default:
1370			pci_info(dev, "not setting up bridge for bus %04x:%02x\n",
1371				 pci_domain_nr(b), b->number);
1372			break;
1373		}
1374	}
1375}
1376
1377void pci_bus_assign_resources(const struct pci_bus *bus)
1378{
1379	__pci_bus_assign_resources(bus, NULL, NULL);
1380}
1381EXPORT_SYMBOL(pci_bus_assign_resources);
1382
1383static void pci_claim_device_resources(struct pci_dev *dev)
1384{
1385	int i;
1386
1387	for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
1388		struct resource *r = &dev->resource[i];
1389
1390		if (!r->flags || r->parent)
1391			continue;
1392
1393		pci_claim_resource(dev, i);
1394	}
1395}
1396
1397static void pci_claim_bridge_resources(struct pci_dev *dev)
1398{
1399	int i;
1400
1401	for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) {
1402		struct resource *r = &dev->resource[i];
1403
1404		if (!r->flags || r->parent)
1405			continue;
1406
1407		pci_claim_bridge_resource(dev, i);
1408	}
1409}
1410
1411static void pci_bus_allocate_dev_resources(struct pci_bus *b)
1412{
1413	struct pci_dev *dev;
1414	struct pci_bus *child;
1415
1416	list_for_each_entry(dev, &b->devices, bus_list) {
1417		pci_claim_device_resources(dev);
1418
1419		child = dev->subordinate;
1420		if (child)
1421			pci_bus_allocate_dev_resources(child);
1422	}
1423}
1424
1425static void pci_bus_allocate_resources(struct pci_bus *b)
1426{
1427	struct pci_bus *child;
1428
1429	/*
1430	 * Carry out a depth-first search on the PCI bus tree to allocate
1431	 * bridge apertures.  Read the programmed bridge bases and
1432	 * recursively claim the respective bridge resources.
1433	 */
1434	if (b->self) {
1435		pci_read_bridge_bases(b);
1436		pci_claim_bridge_resources(b->self);
1437	}
1438
1439	list_for_each_entry(child, &b->children, node)
1440		pci_bus_allocate_resources(child);
1441}
1442
1443void pci_bus_claim_resources(struct pci_bus *b)
1444{
1445	pci_bus_allocate_resources(b);
1446	pci_bus_allocate_dev_resources(b);
1447}
1448EXPORT_SYMBOL(pci_bus_claim_resources);
1449
1450static void __pci_bridge_assign_resources(const struct pci_dev *bridge,
1451					  struct list_head *add_head,
1452					  struct list_head *fail_head)
1453{
1454	struct pci_bus *b;
1455
1456	pdev_assign_resources_sorted((struct pci_dev *)bridge,
1457					 add_head, fail_head);
1458
1459	b = bridge->subordinate;
1460	if (!b)
1461		return;
1462
1463	__pci_bus_assign_resources(b, add_head, fail_head);
1464
1465	switch (bridge->class >> 8) {
1466	case PCI_CLASS_BRIDGE_PCI:
1467		pci_setup_bridge(b);
1468		break;
1469
1470	case PCI_CLASS_BRIDGE_CARDBUS:
1471		pci_setup_cardbus(b);
1472		break;
1473
1474	default:
1475		pci_info(bridge, "not setting up bridge for bus %04x:%02x\n",
1476			 pci_domain_nr(b), b->number);
1477		break;
1478	}
1479}
1480
1481#define PCI_RES_TYPE_MASK \
1482	(IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH |\
1483	 IORESOURCE_MEM_64)
1484
1485static void pci_bridge_release_resources(struct pci_bus *bus,
1486					 unsigned long type)
1487{
1488	struct pci_dev *dev = bus->self;
1489	struct resource *r;
 
 
1490	unsigned old_flags = 0;
1491	struct resource *b_res;
1492	int idx = 1;
1493
1494	b_res = &dev->resource[PCI_BRIDGE_RESOURCES];
1495
1496	/*
1497	 * 1. If IO port assignment fails, release bridge IO port.
1498	 * 2. If non pref MMIO assignment fails, release bridge nonpref MMIO.
1499	 * 3. If 64bit pref MMIO assignment fails, and bridge pref is 64bit,
1500	 *    release bridge pref MMIO.
1501	 * 4. If pref MMIO assignment fails, and bridge pref is 32bit,
1502	 *    release bridge pref MMIO.
1503	 * 5. If pref MMIO assignment fails, and bridge pref is not
1504	 *    assigned, release bridge nonpref MMIO.
 
 
1505	 */
1506	if (type & IORESOURCE_IO)
1507		idx = 0;
1508	else if (!(type & IORESOURCE_PREFETCH))
1509		idx = 1;
1510	else if ((type & IORESOURCE_MEM_64) &&
1511		 (b_res[2].flags & IORESOURCE_MEM_64))
1512		idx = 2;
1513	else if (!(b_res[2].flags & IORESOURCE_MEM_64) &&
1514		 (b_res[2].flags & IORESOURCE_PREFETCH))
1515		idx = 2;
1516	else
1517		idx = 1;
1518
1519	r = &b_res[idx];
1520
1521	if (!r->parent)
1522		return;
1523
1524	/* If there are children, release them all */
 
 
 
1525	release_child_resources(r);
1526	if (!release_resource(r)) {
1527		type = old_flags = r->flags & PCI_RES_TYPE_MASK;
1528		pci_info(dev, "resource %d %pR released\n",
1529			 PCI_BRIDGE_RESOURCES + idx, r);
1530		/* Keep the old size */
1531		r->end = resource_size(r) - 1;
1532		r->start = 0;
1533		r->flags = 0;
1534
1535		/* Avoiding touch the one without PREF */
1536		if (type & IORESOURCE_PREFETCH)
1537			type = IORESOURCE_PREFETCH;
1538		__pci_setup_bridge(bus, type);
1539		/* For next child res under same bridge */
1540		r->flags = old_flags;
1541	}
1542}
1543
1544enum release_type {
1545	leaf_only,
1546	whole_subtree,
1547};
1548
1549/*
1550 * Try to release PCI bridge resources from leaf bridge, so we can allocate
1551 * a larger window later.
1552 */
1553static void pci_bus_release_bridge_resources(struct pci_bus *bus,
1554					     unsigned long type,
1555					     enum release_type rel_type)
1556{
1557	struct pci_dev *dev;
1558	bool is_leaf_bridge = true;
1559
1560	list_for_each_entry(dev, &bus->devices, bus_list) {
1561		struct pci_bus *b = dev->subordinate;
1562		if (!b)
1563			continue;
1564
1565		is_leaf_bridge = false;
1566
1567		if ((dev->class >> 8) != PCI_CLASS_BRIDGE_PCI)
1568			continue;
1569
1570		if (rel_type == whole_subtree)
1571			pci_bus_release_bridge_resources(b, type,
1572						 whole_subtree);
1573	}
1574
1575	if (pci_is_root_bus(bus))
1576		return;
1577
1578	if ((bus->self->class >> 8) != PCI_CLASS_BRIDGE_PCI)
1579		return;
1580
1581	if ((rel_type == whole_subtree) || is_leaf_bridge)
1582		pci_bridge_release_resources(bus, type);
1583}
1584
1585static void pci_bus_dump_res(struct pci_bus *bus)
1586{
1587	struct resource *res;
1588	int i;
1589
1590	pci_bus_for_each_resource(bus, res, i) {
1591		if (!res || !res->end || !res->flags)
1592			continue;
1593
1594		dev_info(&bus->dev, "resource %d %pR\n", i, res);
1595	}
1596}
1597
1598static void pci_bus_dump_resources(struct pci_bus *bus)
1599{
1600	struct pci_bus *b;
1601	struct pci_dev *dev;
1602
1603
1604	pci_bus_dump_res(bus);
1605
1606	list_for_each_entry(dev, &bus->devices, bus_list) {
1607		b = dev->subordinate;
1608		if (!b)
1609			continue;
1610
1611		pci_bus_dump_resources(b);
1612	}
1613}
1614
1615static int pci_bus_get_depth(struct pci_bus *bus)
1616{
1617	int depth = 0;
1618	struct pci_bus *child_bus;
1619
1620	list_for_each_entry(child_bus, &bus->children, node) {
1621		int ret;
1622
1623		ret = pci_bus_get_depth(child_bus);
1624		if (ret + 1 > depth)
1625			depth = ret + 1;
1626	}
1627
1628	return depth;
1629}
1630
1631/*
1632 * -1: undefined, will auto detect later
1633 *  0: disabled by user
1634 *  1: disabled by auto detect
1635 *  2: enabled by user
1636 *  3: enabled by auto detect
1637 */
1638enum enable_type {
1639	undefined = -1,
1640	user_disabled,
1641	auto_disabled,
1642	user_enabled,
1643	auto_enabled,
1644};
1645
1646static enum enable_type pci_realloc_enable = undefined;
1647void __init pci_realloc_get_opt(char *str)
1648{
1649	if (!strncmp(str, "off", 3))
1650		pci_realloc_enable = user_disabled;
1651	else if (!strncmp(str, "on", 2))
1652		pci_realloc_enable = user_enabled;
1653}
1654static bool pci_realloc_enabled(enum enable_type enable)
1655{
1656	return enable >= user_enabled;
1657}
1658
1659#if defined(CONFIG_PCI_IOV) && defined(CONFIG_PCI_REALLOC_ENABLE_AUTO)
1660static int iov_resources_unassigned(struct pci_dev *dev, void *data)
1661{
1662	int i;
1663	bool *unassigned = data;
1664
1665	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
1666		struct resource *r = &dev->resource[i + PCI_IOV_RESOURCES];
1667		struct pci_bus_region region;
1668
1669		/* Not assigned or rejected by kernel? */
1670		if (!r->flags)
1671			continue;
1672
1673		pcibios_resource_to_bus(dev->bus, &region, r);
1674		if (!region.start) {
1675			*unassigned = true;
1676			return 1; /* Return early from pci_walk_bus() */
1677		}
1678	}
1679
1680	return 0;
1681}
1682
1683static enum enable_type pci_realloc_detect(struct pci_bus *bus,
1684					   enum enable_type enable_local)
1685{
1686	bool unassigned = false;
1687	struct pci_host_bridge *host;
1688
1689	if (enable_local != undefined)
1690		return enable_local;
1691
1692	host = pci_find_host_bridge(bus);
1693	if (host->preserve_config)
1694		return auto_disabled;
1695
1696	pci_walk_bus(bus, iov_resources_unassigned, &unassigned);
1697	if (unassigned)
1698		return auto_enabled;
1699
1700	return enable_local;
1701}
1702#else
1703static enum enable_type pci_realloc_detect(struct pci_bus *bus,
1704					   enum enable_type enable_local)
1705{
1706	return enable_local;
1707}
1708#endif
1709
1710/*
1711 * First try will not touch PCI bridge res.
1712 * Second and later try will clear small leaf bridge res.
1713 * Will stop till to the max depth if can not find good one.
1714 */
1715void pci_assign_unassigned_root_bus_resources(struct pci_bus *bus)
1716{
1717	LIST_HEAD(realloc_head);
1718	/* List of resources that want additional resources */
1719	struct list_head *add_list = NULL;
1720	int tried_times = 0;
1721	enum release_type rel_type = leaf_only;
1722	LIST_HEAD(fail_head);
1723	struct pci_dev_resource *fail_res;
 
 
1724	int pci_try_num = 1;
1725	enum enable_type enable_local;
1726
1727	/* Don't realloc if asked to do so */
1728	enable_local = pci_realloc_detect(bus, pci_realloc_enable);
1729	if (pci_realloc_enabled(enable_local)) {
1730		int max_depth = pci_bus_get_depth(bus);
1731
1732		pci_try_num = max_depth + 1;
1733		dev_info(&bus->dev, "max bus depth: %d pci_try_num: %d\n",
1734			 max_depth, pci_try_num);
 
1735	}
1736
1737again:
1738	/*
1739	 * Last try will use add_list, otherwise will try good to have as must
1740	 * have, so can realloc parent bridge resource
1741	 */
1742	if (tried_times + 1 == pci_try_num)
1743		add_list = &realloc_head;
1744	/*
1745	 * Depth first, calculate sizes and alignments of all subordinate buses.
1746	 */
1747	__pci_bus_size_bridges(bus, add_list);
1748
1749	/* Depth last, allocate resources and update the hardware. */
1750	__pci_bus_assign_resources(bus, add_list, &fail_head);
1751	if (add_list)
1752		BUG_ON(!list_empty(add_list));
1753	tried_times++;
1754
1755	/* Any device complain? */
1756	if (list_empty(&fail_head))
1757		goto dump;
1758
1759	if (tried_times >= pci_try_num) {
1760		if (enable_local == undefined)
1761			dev_info(&bus->dev, "Some PCI device resources are unassigned, try booting with pci=realloc\n");
1762		else if (enable_local == auto_enabled)
1763			dev_info(&bus->dev, "Automatically enabled pci realloc, if you have problem, try booting with pci=realloc=off\n");
1764
1765		free_list(&fail_head);
1766		goto dump;
1767	}
1768
1769	dev_info(&bus->dev, "No. %d try to assign unassigned res\n",
1770		 tried_times + 1);
1771
1772	/* Third times and later will not check if it is leaf */
1773	if ((tried_times + 1) > 2)
1774		rel_type = whole_subtree;
1775
1776	/*
1777	 * Try to release leaf bridge's resources that doesn't fit resource of
1778	 * child device under that bridge.
1779	 */
1780	list_for_each_entry(fail_res, &fail_head, list)
1781		pci_bus_release_bridge_resources(fail_res->dev->bus,
1782						 fail_res->flags & PCI_RES_TYPE_MASK,
1783						 rel_type);
1784
1785	/* Restore size and flags */
1786	list_for_each_entry(fail_res, &fail_head, list) {
1787		struct resource *res = fail_res->res;
1788
1789		res->start = fail_res->start;
1790		res->end = fail_res->end;
1791		res->flags = fail_res->flags;
1792		if (fail_res->dev->subordinate)
1793			res->flags = 0;
1794	}
1795	free_list(&fail_head);
1796
1797	goto again;
1798
1799dump:
1800	/* Dump the resource on buses */
1801	pci_bus_dump_resources(bus);
1802}
1803
1804void __init pci_assign_unassigned_resources(void)
1805{
1806	struct pci_bus *root_bus;
1807
1808	list_for_each_entry(root_bus, &pci_root_buses, node) {
1809		pci_assign_unassigned_root_bus_resources(root_bus);
1810
1811		/* Make sure the root bridge has a companion ACPI device */
1812		if (ACPI_HANDLE(root_bus->bridge))
1813			acpi_ioapic_add(ACPI_HANDLE(root_bus->bridge));
1814	}
1815}
1816
1817static void extend_bridge_window(struct pci_dev *bridge, struct resource *res,
1818				 struct list_head *add_list,
1819				 resource_size_t available)
1820{
1821	struct pci_dev_resource *dev_res;
1822
1823	if (res->parent)
1824		return;
1825
1826	if (resource_size(res) >= available)
1827		return;
1828
1829	dev_res = res_to_dev_res(add_list, res);
1830	if (!dev_res)
1831		return;
1832
1833	/* Is there room to extend the window? */
1834	if (available - resource_size(res) <= dev_res->add_size)
1835		return;
1836
1837	dev_res->add_size = available - resource_size(res);
1838	pci_dbg(bridge, "bridge window %pR extended by %pa\n", res,
1839		&dev_res->add_size);
1840}
1841
1842static void pci_bus_distribute_available_resources(struct pci_bus *bus,
1843					    struct list_head *add_list,
1844					    resource_size_t available_io,
1845					    resource_size_t available_mmio,
1846					    resource_size_t available_mmio_pref)
1847{
1848	resource_size_t remaining_io, remaining_mmio, remaining_mmio_pref;
1849	unsigned int normal_bridges = 0, hotplug_bridges = 0;
1850	struct resource *io_res, *mmio_res, *mmio_pref_res;
1851	struct pci_dev *dev, *bridge = bus->self;
1852
1853	io_res = &bridge->resource[PCI_BRIDGE_RESOURCES + 0];
1854	mmio_res = &bridge->resource[PCI_BRIDGE_RESOURCES + 1];
1855	mmio_pref_res = &bridge->resource[PCI_BRIDGE_RESOURCES + 2];
1856
1857	/*
1858	 * Update additional resource list (add_list) to fill all the
1859	 * extra resource space available for this port except the space
1860	 * calculated in __pci_bus_size_bridges() which covers all the
1861	 * devices currently connected to the port and below.
1862	 */
1863	extend_bridge_window(bridge, io_res, add_list, available_io);
1864	extend_bridge_window(bridge, mmio_res, add_list, available_mmio);
1865	extend_bridge_window(bridge, mmio_pref_res, add_list,
1866			     available_mmio_pref);
1867
1868	/*
1869	 * Calculate how many hotplug bridges and normal bridges there
1870	 * are on this bus.  We will distribute the additional available
1871	 * resources between hotplug bridges.
1872	 */
1873	for_each_pci_bridge(dev, bus) {
1874		if (dev->is_hotplug_bridge)
1875			hotplug_bridges++;
1876		else
1877			normal_bridges++;
1878	}
1879
1880	/*
1881	 * There is only one bridge on the bus so it gets all available
1882	 * resources which it can then distribute to the possible hotplug
1883	 * bridges below.
1884	 */
1885	if (hotplug_bridges + normal_bridges == 1) {
1886		dev = list_first_entry(&bus->devices, struct pci_dev, bus_list);
1887		if (dev->subordinate) {
1888			pci_bus_distribute_available_resources(dev->subordinate,
1889				add_list, available_io, available_mmio,
1890				available_mmio_pref);
1891		}
1892		return;
1893	}
1894
1895	if (hotplug_bridges == 0)
1896		return;
1897
1898	/*
1899	 * Calculate the total amount of extra resource space we can
1900	 * pass to bridges below this one.  This is basically the
1901	 * extra space reduced by the minimal required space for the
1902	 * non-hotplug bridges.
1903	 */
1904	remaining_io = available_io;
1905	remaining_mmio = available_mmio;
1906	remaining_mmio_pref = available_mmio_pref;
1907
1908	for_each_pci_bridge(dev, bus) {
1909		const struct resource *res;
1910
1911		if (dev->is_hotplug_bridge)
1912			continue;
1913
1914		/*
1915		 * Reduce the available resource space by what the
1916		 * bridge and devices below it occupy.
1917		 */
1918		res = &dev->resource[PCI_BRIDGE_RESOURCES + 0];
1919		if (!res->parent && available_io > resource_size(res))
1920			remaining_io -= resource_size(res);
1921
1922		res = &dev->resource[PCI_BRIDGE_RESOURCES + 1];
1923		if (!res->parent && available_mmio > resource_size(res))
1924			remaining_mmio -= resource_size(res);
1925
1926		res = &dev->resource[PCI_BRIDGE_RESOURCES + 2];
1927		if (!res->parent && available_mmio_pref > resource_size(res))
1928			remaining_mmio_pref -= resource_size(res);
1929	}
1930
1931	/*
1932	 * Go over devices on this bus and distribute the remaining
1933	 * resource space between hotplug bridges.
1934	 */
1935	for_each_pci_bridge(dev, bus) {
1936		resource_size_t align, io, mmio, mmio_pref;
1937		struct pci_bus *b;
1938
1939		b = dev->subordinate;
1940		if (!b || !dev->is_hotplug_bridge)
1941			continue;
1942
1943		/*
1944		 * Distribute available extra resources equally between
1945		 * hotplug-capable downstream ports taking alignment into
1946		 * account.
1947		 */
1948		align = pci_resource_alignment(bridge, io_res);
1949		io = div64_ul(available_io, hotplug_bridges);
1950		io = min(ALIGN(io, align), remaining_io);
1951		remaining_io -= io;
1952
1953		align = pci_resource_alignment(bridge, mmio_res);
1954		mmio = div64_ul(available_mmio, hotplug_bridges);
1955		mmio = min(ALIGN(mmio, align), remaining_mmio);
1956		remaining_mmio -= mmio;
1957
1958		align = pci_resource_alignment(bridge, mmio_pref_res);
1959		mmio_pref = div64_ul(available_mmio_pref, hotplug_bridges);
1960		mmio_pref = min(ALIGN(mmio_pref, align), remaining_mmio_pref);
1961		remaining_mmio_pref -= mmio_pref;
1962
1963		pci_bus_distribute_available_resources(b, add_list, io, mmio,
1964						       mmio_pref);
1965	}
1966}
1967
1968static void pci_bridge_distribute_available_resources(struct pci_dev *bridge,
1969						     struct list_head *add_list)
1970{
1971	resource_size_t available_io, available_mmio, available_mmio_pref;
1972	const struct resource *res;
1973
1974	if (!bridge->is_hotplug_bridge)
1975		return;
1976
1977	/* Take the initial extra resources from the hotplug port */
1978	res = &bridge->resource[PCI_BRIDGE_RESOURCES + 0];
1979	available_io = resource_size(res);
1980	res = &bridge->resource[PCI_BRIDGE_RESOURCES + 1];
1981	available_mmio = resource_size(res);
1982	res = &bridge->resource[PCI_BRIDGE_RESOURCES + 2];
1983	available_mmio_pref = resource_size(res);
1984
1985	pci_bus_distribute_available_resources(bridge->subordinate,
1986					       add_list, available_io,
1987					       available_mmio,
1988					       available_mmio_pref);
1989}
1990
1991void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge)
1992{
1993	struct pci_bus *parent = bridge->subordinate;
1994	/* List of resources that want additional resources */
1995	LIST_HEAD(add_list);
1996
1997	int tried_times = 0;
1998	LIST_HEAD(fail_head);
1999	struct pci_dev_resource *fail_res;
2000	int retval;
 
 
2001
2002again:
2003	__pci_bus_size_bridges(parent, &add_list);
2004
2005	/*
2006	 * Distribute remaining resources (if any) equally between hotplug
2007	 * bridges below.  This makes it possible to extend the hierarchy
2008	 * later without running out of resources.
2009	 */
2010	pci_bridge_distribute_available_resources(bridge, &add_list);
2011
2012	__pci_bridge_assign_resources(bridge, &add_list, &fail_head);
2013	BUG_ON(!list_empty(&add_list));
2014	tried_times++;
2015
2016	if (list_empty(&fail_head))
2017		goto enable_all;
2018
2019	if (tried_times >= 2) {
2020		/* Still fail, don't need to try more */
2021		free_list(&fail_head);
2022		goto enable_all;
2023	}
2024
2025	printk(KERN_DEBUG "PCI: No. %d try to assign unassigned res\n",
2026			 tried_times + 1);
2027
2028	/*
2029	 * Try to release leaf bridge's resources that aren't big enough
2030	 * to contain child device resources.
2031	 */
2032	list_for_each_entry(fail_res, &fail_head, list)
2033		pci_bus_release_bridge_resources(fail_res->dev->bus,
2034						 fail_res->flags & PCI_RES_TYPE_MASK,
2035						 whole_subtree);
2036
2037	/* Restore size and flags */
2038	list_for_each_entry(fail_res, &fail_head, list) {
2039		struct resource *res = fail_res->res;
2040
2041		res->start = fail_res->start;
2042		res->end = fail_res->end;
2043		res->flags = fail_res->flags;
2044		if (fail_res->dev->subordinate)
2045			res->flags = 0;
2046	}
2047	free_list(&fail_head);
2048
2049	goto again;
2050
2051enable_all:
2052	retval = pci_reenable_device(bridge);
2053	if (retval)
2054		pci_err(bridge, "Error reenabling bridge (%d)\n", retval);
2055	pci_set_master(bridge);
2056}
2057EXPORT_SYMBOL_GPL(pci_assign_unassigned_bridge_resources);
2058
2059int pci_reassign_bridge_resources(struct pci_dev *bridge, unsigned long type)
2060{
2061	struct pci_dev_resource *dev_res;
2062	struct pci_dev *next;
2063	LIST_HEAD(saved);
2064	LIST_HEAD(added);
2065	LIST_HEAD(failed);
2066	unsigned int i;
2067	int ret;
2068
2069	/* Walk to the root hub, releasing bridge BARs when possible */
2070	next = bridge;
2071	do {
2072		bridge = next;
2073		for (i = PCI_BRIDGE_RESOURCES; i < PCI_BRIDGE_RESOURCE_END;
2074		     i++) {
2075			struct resource *res = &bridge->resource[i];
2076
2077			if ((res->flags ^ type) & PCI_RES_TYPE_MASK)
2078				continue;
2079
2080			/* Ignore BARs which are still in use */
2081			if (res->child)
2082				continue;
2083
2084			ret = add_to_list(&saved, bridge, res, 0, 0);
2085			if (ret)
2086				goto cleanup;
2087
2088			pci_info(bridge, "BAR %d: releasing %pR\n",
2089				 i, res);
2090
2091			if (res->parent)
2092				release_resource(res);
2093			res->start = 0;
2094			res->end = 0;
2095			break;
2096		}
2097		if (i == PCI_BRIDGE_RESOURCE_END)
2098			break;
2099
2100		next = bridge->bus ? bridge->bus->self : NULL;
2101	} while (next);
2102
2103	if (list_empty(&saved))
2104		return -ENOENT;
2105
2106	__pci_bus_size_bridges(bridge->subordinate, &added);
2107	__pci_bridge_assign_resources(bridge, &added, &failed);
2108	BUG_ON(!list_empty(&added));
2109
2110	if (!list_empty(&failed)) {
2111		ret = -ENOSPC;
2112		goto cleanup;
2113	}
2114
2115	list_for_each_entry(dev_res, &saved, list) {
2116		/* Skip the bridge we just assigned resources for */
2117		if (bridge == dev_res->dev)
2118			continue;
2119
2120		bridge = dev_res->dev;
2121		pci_setup_bridge(bridge->subordinate);
2122	}
2123
2124	free_list(&saved);
2125	return 0;
2126
2127cleanup:
2128	/* Restore size and flags */
2129	list_for_each_entry(dev_res, &failed, list) {
2130		struct resource *res = dev_res->res;
2131
2132		res->start = dev_res->start;
2133		res->end = dev_res->end;
2134		res->flags = dev_res->flags;
2135	}
2136	free_list(&failed);
2137
2138	/* Revert to the old configuration */
2139	list_for_each_entry(dev_res, &saved, list) {
2140		struct resource *res = dev_res->res;
2141
2142		bridge = dev_res->dev;
2143		i = res - bridge->resource;
2144
2145		res->start = dev_res->start;
2146		res->end = dev_res->end;
2147		res->flags = dev_res->flags;
2148
2149		pci_claim_resource(bridge, i);
2150		pci_setup_bridge(bridge->subordinate);
2151	}
2152	free_list(&saved);
2153
2154	return ret;
2155}
2156
2157void pci_assign_unassigned_bus_resources(struct pci_bus *bus)
2158{
2159	struct pci_dev *dev;
2160	/* List of resources that want additional resources */
2161	LIST_HEAD(add_list);
2162
2163	down_read(&pci_bus_sem);
2164	for_each_pci_bridge(dev, bus)
2165		if (pci_has_subordinate(dev))
2166			__pci_bus_size_bridges(dev->subordinate, &add_list);
 
2167	up_read(&pci_bus_sem);
2168	__pci_bus_assign_resources(bus, &add_list, NULL);
2169	BUG_ON(!list_empty(&add_list));
2170}
2171EXPORT_SYMBOL_GPL(pci_assign_unassigned_bus_resources);