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;
  29EXPORT_SYMBOL_GPL(pci_flags);
  30
  31struct pci_dev_resource {
  32	struct list_head list;
  33	struct resource *res;
  34	struct pci_dev *dev;
  35	resource_size_t start;
  36	resource_size_t end;
  37	resource_size_t add_size;
  38	resource_size_t min_align;
  39	unsigned long flags;
  40};
  41
  42static void free_list(struct list_head *head)
  43{
  44	struct pci_dev_resource *dev_res, *tmp;
  45
  46	list_for_each_entry_safe(dev_res, tmp, head, list) {
  47		list_del(&dev_res->list);
  48		kfree(dev_res);
  49	}
  50}
  51
  52/**
  53 * add_to_list() - Add a new resource tracker to the list
  54 * @head:	Head of the list
  55 * @dev:	Device to which the resource belongs
  56 * @res:	Resource to be tracked
  57 * @add_size:	Additional size to be optionally added to the resource
  58 * @min_align:	Minimum memory window alignment
 
  59 */
  60static int add_to_list(struct list_head *head, struct pci_dev *dev,
  61		       struct resource *res, resource_size_t add_size,
  62		       resource_size_t min_align)
  63{
  64	struct pci_dev_resource *tmp;
  65
  66	tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
  67	if (!tmp)
 
  68		return -ENOMEM;
 
  69
  70	tmp->res = res;
  71	tmp->dev = dev;
  72	tmp->start = res->start;
  73	tmp->end = res->end;
  74	tmp->flags = res->flags;
  75	tmp->add_size = add_size;
  76	tmp->min_align = min_align;
  77
  78	list_add(&tmp->list, head);
  79
  80	return 0;
  81}
  82
  83static void remove_from_list(struct list_head *head, struct resource *res)
 
  84{
  85	struct pci_dev_resource *dev_res, *tmp;
  86
  87	list_for_each_entry_safe(dev_res, tmp, head, list) {
  88		if (dev_res->res == res) {
  89			list_del(&dev_res->list);
  90			kfree(dev_res);
  91			break;
  92		}
  93	}
  94}
  95
  96static struct pci_dev_resource *res_to_dev_res(struct list_head *head,
  97					       struct resource *res)
  98{
  99	struct pci_dev_resource *dev_res;
 100
 101	list_for_each_entry(dev_res, head, list) {
 102		if (dev_res->res == res)
 
 
 
 
 
 
 
 
 103			return dev_res;
 
 104	}
 105
 106	return NULL;
 107}
 108
 109static resource_size_t get_res_add_size(struct list_head *head,
 110					struct resource *res)
 111{
 112	struct pci_dev_resource *dev_res;
 113
 114	dev_res = res_to_dev_res(head, res);
 115	return dev_res ? dev_res->add_size : 0;
 116}
 117
 118static resource_size_t get_res_add_align(struct list_head *head,
 119					 struct resource *res)
 120{
 121	struct pci_dev_resource *dev_res;
 122
 123	dev_res = res_to_dev_res(head, res);
 124	return dev_res ? dev_res->min_align : 0;
 125}
 126
 127
 128/* Sort resources by alignment */
 129static void pdev_sort_resources(struct pci_dev *dev, struct list_head *head)
 130{
 131	int i;
 132
 133	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
 134		struct resource *r;
 135		struct pci_dev_resource *dev_res, *tmp;
 136		resource_size_t r_align;
 137		struct list_head *n;
 138
 139		r = &dev->resource[i];
 140
 141		if (r->flags & IORESOURCE_PCI_FIXED)
 142			continue;
 143
 144		if (!(r->flags) || r->parent)
 145			continue;
 146
 147		r_align = pci_resource_alignment(dev, r);
 148		if (!r_align) {
 149			pci_warn(dev, "BAR %d: %pR has bogus alignment\n",
 150				 i, r);
 151			continue;
 152		}
 153
 154		tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
 155		if (!tmp)
 156			panic("%s: kzalloc() failed!\n", __func__);
 157		tmp->res = r;
 158		tmp->dev = dev;
 159
 160		/* Fallback is smallest one or list is empty */
 161		n = head;
 162		list_for_each_entry(dev_res, head, list) {
 163			resource_size_t align;
 164
 165			align = pci_resource_alignment(dev_res->dev,
 166							 dev_res->res);
 167
 168			if (r_align > align) {
 169				n = &dev_res->list;
 170				break;
 171			}
 172		}
 173		/* Insert it just before n */
 174		list_add_tail(&tmp->list, n);
 175	}
 176}
 177
 178static void __dev_sort_resources(struct pci_dev *dev, struct list_head *head)
 
 179{
 180	u16 class = dev->class >> 8;
 181
 182	/* Don't touch classless devices or host bridges or IOAPICs */
 183	if (class == PCI_CLASS_NOT_DEFINED || class == PCI_CLASS_BRIDGE_HOST)
 184		return;
 185
 186	/* Don't touch IOAPIC devices already enabled by firmware */
 187	if (class == PCI_CLASS_SYSTEM_PIC) {
 188		u16 command;
 189		pci_read_config_word(dev, PCI_COMMAND, &command);
 190		if (command & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY))
 191			return;
 192	}
 193
 194	pdev_sort_resources(dev, head);
 195}
 196
 197static inline void reset_resource(struct resource *res)
 198{
 199	res->start = 0;
 200	res->end = 0;
 201	res->flags = 0;
 202}
 203
 204/**
 205 * reassign_resources_sorted() - Satisfy any additional resource requests
 206 *
 207 * @realloc_head:	Head of the list tracking requests requiring
 208 *			additional resources
 209 * @head:		Head of the list tracking requests with allocated
 210 *			resources
 211 *
 212 * Walk through each element of the realloc_head and try to procure additional
 213 * resources for the element, provided the element is in the head list.
 
 214 */
 215static void reassign_resources_sorted(struct list_head *realloc_head,
 216				      struct list_head *head)
 217{
 218	struct resource *res;
 219	struct pci_dev_resource *add_res, *tmp;
 220	struct pci_dev_resource *dev_res;
 221	resource_size_t add_size, align;
 222	int idx;
 223
 224	list_for_each_entry_safe(add_res, tmp, realloc_head, list) {
 225		bool found_match = false;
 226
 227		res = add_res->res;
 228		/* Skip resource that has been reset */
 229		if (!res->flags)
 230			goto out;
 231
 232		/* Skip this resource if not found in head list */
 233		list_for_each_entry(dev_res, head, list) {
 234			if (dev_res->res == res) {
 235				found_match = true;
 236				break;
 237			}
 238		}
 239		if (!found_match) /* Just skip */
 240			continue;
 241
 242		idx = res - &add_res->dev->resource[0];
 243		add_size = add_res->add_size;
 244		align = add_res->min_align;
 245		if (!resource_size(res)) {
 246			res->start = align;
 247			res->end = res->start + add_size - 1;
 248			if (pci_assign_resource(add_res->dev, idx))
 249				reset_resource(res);
 250		} else {
 251			res->flags |= add_res->flags &
 252				 (IORESOURCE_STARTALIGN|IORESOURCE_SIZEALIGN);
 253			if (pci_reassign_resource(add_res->dev, idx,
 254						  add_size, align))
 255				pci_info(add_res->dev, "failed to add %llx res[%d]=%pR\n",
 256					 (unsigned long long) add_size, idx,
 257					 res);
 
 258		}
 259out:
 260		list_del(&add_res->list);
 261		kfree(add_res);
 262	}
 263}
 264
 265/**
 266 * assign_requested_resources_sorted() - Satisfy resource requests
 267 *
 268 * @head:	Head of the list tracking requests for resources
 269 * @fail_head:	Head of the list tracking requests that could not be
 270 *		allocated
 271 *
 272 * Satisfy resource requests of each element in the list.  Add requests that
 273 * could not be satisfied to the failed_list.
 274 */
 275static void assign_requested_resources_sorted(struct list_head *head,
 276				 struct list_head *fail_head)
 277{
 278	struct resource *res;
 279	struct pci_dev_resource *dev_res;
 280	int idx;
 281
 282	list_for_each_entry(dev_res, head, list) {
 283		res = dev_res->res;
 284		idx = res - &dev_res->dev->resource[0];
 285		if (resource_size(res) &&
 286		    pci_assign_resource(dev_res->dev, idx)) {
 287			if (fail_head) {
 288				/*
 289				 * If the failed resource is a ROM BAR and
 290				 * it will be enabled later, don't add it
 291				 * to the list.
 292				 */
 293				if (!((idx == PCI_ROM_RESOURCE) &&
 294				      (!(res->flags & IORESOURCE_ROM_ENABLE))))
 295					add_to_list(fail_head,
 296						    dev_res->dev, res,
 297						    0 /* don't care */,
 298						    0 /* don't care */);
 299			}
 300			reset_resource(res);
 301		}
 302	}
 303}
 304
 305static unsigned long pci_fail_res_type_mask(struct list_head *fail_head)
 306{
 307	struct pci_dev_resource *fail_res;
 308	unsigned long mask = 0;
 309
 310	/* Check failed type */
 311	list_for_each_entry(fail_res, fail_head, list)
 312		mask |= fail_res->flags;
 313
 314	/*
 315	 * One pref failed resource will set IORESOURCE_MEM, as we can
 316	 * allocate pref in non-pref range.  Will release all assigned
 317	 * non-pref sibling resources according to that bit.
 
 318	 */
 319	return mask & (IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH);
 320}
 321
 322static bool pci_need_to_release(unsigned long mask, struct resource *res)
 323{
 324	if (res->flags & IORESOURCE_IO)
 325		return !!(mask & IORESOURCE_IO);
 326
 327	/* Check pref at first */
 328	if (res->flags & IORESOURCE_PREFETCH) {
 329		if (mask & IORESOURCE_PREFETCH)
 330			return true;
 331		/* Count pref if its parent is non-pref */
 332		else if ((mask & IORESOURCE_MEM) &&
 333			 !(res->parent->flags & IORESOURCE_PREFETCH))
 334			return true;
 335		else
 336			return false;
 337	}
 338
 339	if (res->flags & IORESOURCE_MEM)
 340		return !!(mask & IORESOURCE_MEM);
 341
 342	return false;	/* Should not get here */
 343}
 344
 345static void __assign_resources_sorted(struct list_head *head,
 346				      struct list_head *realloc_head,
 347				      struct list_head *fail_head)
 348{
 349	/*
 350	 * Should not assign requested resources at first.  They could be
 351	 * adjacent, so later reassign can not reallocate them one by one in
 352	 * parent resource window.
 353	 *
 354	 * Try to assign requested + add_size at beginning.  If could do that,
 355	 * could get out early.  If could not do that, we still try to assign
 356	 * requested at first, then try to reassign add_size for some resources.
 357	 *
 358	 * Separate three resource type checking if we need to release
 359	 * assigned resource after requested + add_size try.
 360	 *
 361	 *	1. If IO port assignment fails, will release assigned IO
 362	 *	   port.
 363	 *	2. If pref MMIO assignment fails, release assigned pref
 364	 *	   MMIO.  If assigned pref MMIO's parent is non-pref MMIO
 365	 *	   and non-pref MMIO assignment fails, will release that
 366	 *	   assigned pref MMIO.
 367	 *	3. If non-pref MMIO assignment fails or pref MMIO
 368	 *	   assignment fails, will release assigned non-pref MMIO.
 369	 */
 370	LIST_HEAD(save_head);
 371	LIST_HEAD(local_fail_head);
 372	struct pci_dev_resource *save_res;
 373	struct pci_dev_resource *dev_res, *tmp_res, *dev_res2;
 374	unsigned long fail_type;
 375	resource_size_t add_align, align;
 376
 377	/* Check if optional add_size is there */
 378	if (!realloc_head || list_empty(realloc_head))
 379		goto requested_and_reassign;
 380
 381	/* Save original start, end, flags etc at first */
 382	list_for_each_entry(dev_res, head, list) {
 383		if (add_to_list(&save_head, dev_res->dev, dev_res->res, 0, 0)) {
 384			free_list(&save_head);
 385			goto requested_and_reassign;
 386		}
 387	}
 388
 389	/* Update res in head list with add_size in realloc_head list */
 390	list_for_each_entry_safe(dev_res, tmp_res, head, list) {
 391		dev_res->res->end += get_res_add_size(realloc_head,
 392							dev_res->res);
 393
 394		/*
 395		 * There are two kinds of additional resources in the list:
 396		 * 1. bridge resource  -- IORESOURCE_STARTALIGN
 397		 * 2. SR-IOV resource  -- IORESOURCE_SIZEALIGN
 398		 * Here just fix the additional alignment for bridge
 399		 */
 400		if (!(dev_res->res->flags & IORESOURCE_STARTALIGN))
 401			continue;
 402
 403		add_align = get_res_add_align(realloc_head, dev_res->res);
 404
 405		/*
 406		 * The "head" list is sorted by alignment so resources with
 407		 * bigger alignment will be assigned first.  After we
 408		 * change the alignment of a dev_res in "head" list, we
 409		 * need to reorder the list by alignment to make it
 410		 * consistent.
 411		 */
 412		if (add_align > dev_res->res->start) {
 413			resource_size_t r_size = resource_size(dev_res->res);
 414
 415			dev_res->res->start = add_align;
 416			dev_res->res->end = add_align + r_size - 1;
 417
 418			list_for_each_entry(dev_res2, head, list) {
 419				align = pci_resource_alignment(dev_res2->dev,
 420							       dev_res2->res);
 421				if (add_align > align) {
 422					list_move_tail(&dev_res->list,
 423						       &dev_res2->list);
 424					break;
 425				}
 426			}
 427		}
 428
 429	}
 430
 431	/* Try updated head list with add_size added */
 432	assign_requested_resources_sorted(head, &local_fail_head);
 433
 434	/* All assigned with add_size? */
 435	if (list_empty(&local_fail_head)) {
 436		/* Remove head list from realloc_head list */
 437		list_for_each_entry(dev_res, head, list)
 438			remove_from_list(realloc_head, dev_res->res);
 439		free_list(&save_head);
 440		free_list(head);
 441		return;
 442	}
 443
 444	/* Check failed type */
 445	fail_type = pci_fail_res_type_mask(&local_fail_head);
 446	/* Remove not need to be released assigned res from head list etc */
 447	list_for_each_entry_safe(dev_res, tmp_res, head, list)
 448		if (dev_res->res->parent &&
 449		    !pci_need_to_release(fail_type, dev_res->res)) {
 450			/* Remove it from realloc_head list */
 451			remove_from_list(realloc_head, dev_res->res);
 452			remove_from_list(&save_head, dev_res->res);
 453			list_del(&dev_res->list);
 454			kfree(dev_res);
 455		}
 456
 457	free_list(&local_fail_head);
 458	/* Release assigned resource */
 459	list_for_each_entry(dev_res, head, list)
 460		if (dev_res->res->parent)
 461			release_resource(dev_res->res);
 462	/* Restore start/end/flags from saved list */
 463	list_for_each_entry(save_res, &save_head, list) {
 464		struct resource *res = save_res->res;
 465
 466		res->start = save_res->start;
 467		res->end = save_res->end;
 468		res->flags = save_res->flags;
 469	}
 470	free_list(&save_head);
 471
 472requested_and_reassign:
 473	/* Satisfy the must-have resource requests */
 474	assign_requested_resources_sorted(head, fail_head);
 475
 476	/* Try to satisfy any additional optional resource requests */
 
 477	if (realloc_head)
 478		reassign_resources_sorted(realloc_head, head);
 479	free_list(head);
 480}
 481
 482static void pdev_assign_resources_sorted(struct pci_dev *dev,
 483					 struct list_head *add_head,
 484					 struct list_head *fail_head)
 485{
 486	LIST_HEAD(head);
 487
 488	__dev_sort_resources(dev, &head);
 489	__assign_resources_sorted(&head, add_head, fail_head);
 490
 491}
 492
 493static void pbus_assign_resources_sorted(const struct pci_bus *bus,
 494					 struct list_head *realloc_head,
 495					 struct list_head *fail_head)
 496{
 497	struct pci_dev *dev;
 498	LIST_HEAD(head);
 499
 500	list_for_each_entry(dev, &bus->devices, bus_list)
 501		__dev_sort_resources(dev, &head);
 502
 503	__assign_resources_sorted(&head, realloc_head, fail_head);
 504}
 505
 506void pci_setup_cardbus(struct pci_bus *bus)
 507{
 508	struct pci_dev *bridge = bus->self;
 509	struct resource *res;
 510	struct pci_bus_region region;
 511
 512	pci_info(bridge, "CardBus bridge to %pR\n",
 513		 &bus->busn_res);
 514
 515	res = bus->resource[0];
 516	pcibios_resource_to_bus(bridge->bus, &region, res);
 517	if (res->flags & IORESOURCE_IO) {
 518		/*
 519		 * The IO resource is allocated a range twice as large as it
 520		 * would normally need.  This allows us to set both IO regs.
 521		 */
 522		pci_info(bridge, "  bridge window %pR\n", res);
 523		pci_write_config_dword(bridge, PCI_CB_IO_BASE_0,
 524					region.start);
 525		pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_0,
 526					region.end);
 527	}
 528
 529	res = bus->resource[1];
 530	pcibios_resource_to_bus(bridge->bus, &region, res);
 531	if (res->flags & IORESOURCE_IO) {
 532		pci_info(bridge, "  bridge window %pR\n", res);
 533		pci_write_config_dword(bridge, PCI_CB_IO_BASE_1,
 534					region.start);
 535		pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_1,
 536					region.end);
 537	}
 538
 539	res = bus->resource[2];
 540	pcibios_resource_to_bus(bridge->bus, &region, res);
 541	if (res->flags & IORESOURCE_MEM) {
 542		pci_info(bridge, "  bridge window %pR\n", res);
 543		pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_0,
 544					region.start);
 545		pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_0,
 546					region.end);
 547	}
 548
 549	res = bus->resource[3];
 550	pcibios_resource_to_bus(bridge->bus, &region, res);
 551	if (res->flags & IORESOURCE_MEM) {
 552		pci_info(bridge, "  bridge window %pR\n", res);
 553		pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_1,
 554					region.start);
 555		pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_1,
 556					region.end);
 557	}
 558}
 559EXPORT_SYMBOL(pci_setup_cardbus);
 560
 561/*
 562 * Initialize bridges with base/limit values we have collected.  PCI-to-PCI
 563 * Bridge Architecture Specification rev. 1.1 (1998) requires that if there
 564 * are no I/O ports or memory behind the bridge, the corresponding range
 565 * must be turned off by writing base value greater than limit to the
 566 * bridge's base/limit registers.
 567 *
 568 * Note: care must be taken when updating I/O base/limit registers of
 569 * bridges which support 32-bit I/O.  This update requires two config space
 570 * writes, so it's quite possible that an I/O window of the bridge will
 571 * have some undesirable address (e.g. 0) after the first write.  Ditto
 572 * 64-bit prefetchable MMIO.
 573 */
 574static void pci_setup_bridge_io(struct pci_dev *bridge)
 575{
 576	struct resource *res;
 577	struct pci_bus_region region;
 578	unsigned long io_mask;
 579	u8 io_base_lo, io_limit_lo;
 580	u16 l;
 581	u32 io_upper16;
 582
 583	io_mask = PCI_IO_RANGE_MASK;
 584	if (bridge->io_window_1k)
 585		io_mask = PCI_IO_1K_RANGE_MASK;
 586
 587	/* Set up the top and bottom of the PCI I/O segment for this bus */
 588	res = &bridge->resource[PCI_BRIDGE_IO_WINDOW];
 589	pcibios_resource_to_bus(bridge->bus, &region, res);
 590	if (res->flags & IORESOURCE_IO) {
 591		pci_read_config_word(bridge, PCI_IO_BASE, &l);
 592		io_base_lo = (region.start >> 8) & io_mask;
 593		io_limit_lo = (region.end >> 8) & io_mask;
 594		l = ((u16) io_limit_lo << 8) | io_base_lo;
 595		/* Set up upper 16 bits of I/O base/limit */
 596		io_upper16 = (region.end & 0xffff0000) | (region.start >> 16);
 597		pci_info(bridge, "  bridge window %pR\n", res);
 598	} else {
 599		/* Clear upper 16 bits of I/O base/limit */
 600		io_upper16 = 0;
 601		l = 0x00f0;
 602	}
 603	/* Temporarily disable the I/O range before updating PCI_IO_BASE */
 604	pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, 0x0000ffff);
 605	/* Update lower 16 bits of I/O base/limit */
 606	pci_write_config_word(bridge, PCI_IO_BASE, l);
 607	/* Update upper 16 bits of I/O base/limit */
 608	pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, io_upper16);
 609}
 610
 611static void pci_setup_bridge_mmio(struct pci_dev *bridge)
 612{
 613	struct resource *res;
 614	struct pci_bus_region region;
 615	u32 l;
 616
 617	/* Set up the top and bottom of the PCI Memory segment for this bus */
 618	res = &bridge->resource[PCI_BRIDGE_MEM_WINDOW];
 619	pcibios_resource_to_bus(bridge->bus, &region, res);
 620	if (res->flags & IORESOURCE_MEM) {
 621		l = (region.start >> 16) & 0xfff0;
 622		l |= region.end & 0xfff00000;
 623		pci_info(bridge, "  bridge window %pR\n", res);
 624	} else {
 625		l = 0x0000fff0;
 626	}
 627	pci_write_config_dword(bridge, PCI_MEMORY_BASE, l);
 628}
 629
 630static void pci_setup_bridge_mmio_pref(struct pci_dev *bridge)
 631{
 632	struct resource *res;
 633	struct pci_bus_region region;
 634	u32 l, bu, lu;
 635
 636	/*
 637	 * Clear out the upper 32 bits of PREF limit.  If
 638	 * PCI_PREF_BASE_UPPER32 was non-zero, this temporarily disables
 639	 * PREF range, which is ok.
 640	 */
 641	pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, 0);
 642
 643	/* Set up PREF base/limit */
 644	bu = lu = 0;
 645	res = &bridge->resource[PCI_BRIDGE_PREF_MEM_WINDOW];
 646	pcibios_resource_to_bus(bridge->bus, &region, res);
 647	if (res->flags & IORESOURCE_PREFETCH) {
 648		l = (region.start >> 16) & 0xfff0;
 649		l |= region.end & 0xfff00000;
 650		if (res->flags & IORESOURCE_MEM_64) {
 651			bu = upper_32_bits(region.start);
 652			lu = upper_32_bits(region.end);
 653		}
 654		pci_info(bridge, "  bridge window %pR\n", res);
 655	} else {
 656		l = 0x0000fff0;
 657	}
 658	pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l);
 659
 660	/* Set the upper 32 bits of PREF base & limit */
 661	pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, bu);
 662	pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, lu);
 663}
 664
 665static void __pci_setup_bridge(struct pci_bus *bus, unsigned long type)
 666{
 667	struct pci_dev *bridge = bus->self;
 668
 669	pci_info(bridge, "PCI bridge to %pR\n",
 670		 &bus->busn_res);
 671
 672	if (type & IORESOURCE_IO)
 673		pci_setup_bridge_io(bridge);
 674
 675	if (type & IORESOURCE_MEM)
 676		pci_setup_bridge_mmio(bridge);
 677
 678	if (type & IORESOURCE_PREFETCH)
 679		pci_setup_bridge_mmio_pref(bridge);
 680
 681	pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, bus->bridge_ctl);
 682}
 683
 684void __weak pcibios_setup_bridge(struct pci_bus *bus, unsigned long type)
 685{
 686}
 687
 688void pci_setup_bridge(struct pci_bus *bus)
 689{
 690	unsigned long type = IORESOURCE_IO | IORESOURCE_MEM |
 691				  IORESOURCE_PREFETCH;
 692
 693	pcibios_setup_bridge(bus, type);
 694	__pci_setup_bridge(bus, type);
 695}
 696
 697
 698int pci_claim_bridge_resource(struct pci_dev *bridge, int i)
 699{
 700	if (i < PCI_BRIDGE_RESOURCES || i > PCI_BRIDGE_RESOURCE_END)
 701		return 0;
 702
 703	if (pci_claim_resource(bridge, i) == 0)
 704		return 0;	/* Claimed the window */
 705
 706	if ((bridge->class >> 8) != PCI_CLASS_BRIDGE_PCI)
 707		return 0;
 708
 709	if (!pci_bus_clip_resource(bridge, i))
 710		return -EINVAL;	/* Clipping didn't change anything */
 711
 712	switch (i) {
 713	case PCI_BRIDGE_IO_WINDOW:
 714		pci_setup_bridge_io(bridge);
 715		break;
 716	case PCI_BRIDGE_MEM_WINDOW:
 717		pci_setup_bridge_mmio(bridge);
 718		break;
 719	case PCI_BRIDGE_PREF_MEM_WINDOW:
 720		pci_setup_bridge_mmio_pref(bridge);
 721		break;
 722	default:
 723		return -EINVAL;
 724	}
 725
 726	if (pci_claim_resource(bridge, i) == 0)
 727		return 0;	/* Claimed a smaller window */
 728
 729	return -EINVAL;
 730}
 731
 732/*
 733 * Check whether the bridge supports optional I/O and prefetchable memory
 734 * ranges.  If not, the respective base/limit registers must be read-only
 735 * and read as 0.
 736 */
 737static void pci_bridge_check_ranges(struct pci_bus *bus)
 738{
 
 
 739	struct pci_dev *bridge = bus->self;
 740	struct resource *b_res;
 741
 742	b_res = &bridge->resource[PCI_BRIDGE_MEM_WINDOW];
 743	b_res->flags |= IORESOURCE_MEM;
 744
 745	if (bridge->io_window) {
 746		b_res = &bridge->resource[PCI_BRIDGE_IO_WINDOW];
 747		b_res->flags |= IORESOURCE_IO;
 748	}
 
 
 
 
 
 
 
 
 
 
 749
 750	if (bridge->pref_window) {
 751		b_res = &bridge->resource[PCI_BRIDGE_PREF_MEM_WINDOW];
 752		b_res->flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
 753		if (bridge->pref_64_window) {
 754			b_res->flags |= IORESOURCE_MEM_64 |
 755					PCI_PREF_RANGE_TYPE_64;
 
 
 
 
 
 
 
 756		}
 757	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 758}
 759
 760/*
 761 * Helper function for sizing routines.  Assigned resources have non-NULL
 762 * parent resource.
 763 *
 764 * Return first unassigned resource of the correct type.  If there is none,
 765 * return first assigned resource of the correct type.  If none of the
 766 * above, return NULL.
 767 *
 768 * Returning an assigned resource of the correct type allows the caller to
 769 * distinguish between already assigned and no resource of the correct type.
 770 */
 771static struct resource *find_bus_resource_of_type(struct pci_bus *bus,
 772						  unsigned long type_mask,
 773						  unsigned long type)
 774{
 775	struct resource *r, *r_assigned = NULL;
 776	int i;
 
 777
 778	pci_bus_for_each_resource(bus, r, i) {
 779		if (r == &ioport_resource || r == &iomem_resource)
 780			continue;
 781		if (r && (r->flags & type_mask) == type && !r->parent)
 782			return r;
 783		if (r && (r->flags & type_mask) == type && !r_assigned)
 784			r_assigned = r;
 785	}
 786	return r_assigned;
 787}
 788
 789static resource_size_t calculate_iosize(resource_size_t size,
 790					resource_size_t min_size,
 791					resource_size_t size1,
 792					resource_size_t add_size,
 793					resource_size_t children_add_size,
 794					resource_size_t old_size,
 795					resource_size_t align)
 796{
 797	if (size < min_size)
 798		size = min_size;
 799	if (old_size == 1)
 800		old_size = 0;
 801	/*
 802	 * To be fixed in 2.5: we should have sort of HAVE_ISA flag in the
 803	 * struct pci_bus.
 804	 */
 805#if defined(CONFIG_ISA) || defined(CONFIG_EISA)
 806	size = (size & 0xff) + ((size & ~0xffUL) << 2);
 807#endif
 808	size = size + size1;
 809	if (size < old_size)
 810		size = old_size;
 811
 812	size = ALIGN(max(size, add_size) + children_add_size, align);
 813	return size;
 814}
 815
 816static resource_size_t calculate_memsize(resource_size_t size,
 817					 resource_size_t min_size,
 818					 resource_size_t add_size,
 819					 resource_size_t children_add_size,
 820					 resource_size_t old_size,
 821					 resource_size_t align)
 822{
 823	if (size < min_size)
 824		size = min_size;
 825	if (old_size == 1)
 826		old_size = 0;
 827	if (size < old_size)
 828		size = old_size;
 829
 830	size = ALIGN(max(size, add_size) + children_add_size, align);
 831	return size;
 832}
 833
 834resource_size_t __weak pcibios_window_alignment(struct pci_bus *bus,
 835						unsigned long type)
 836{
 837	return 1;
 838}
 839
 840#define PCI_P2P_DEFAULT_MEM_ALIGN	0x100000	/* 1MiB */
 841#define PCI_P2P_DEFAULT_IO_ALIGN	0x1000		/* 4KiB */
 842#define PCI_P2P_DEFAULT_IO_ALIGN_1K	0x400		/* 1KiB */
 843
 844static resource_size_t window_alignment(struct pci_bus *bus, unsigned long type)
 
 845{
 846	resource_size_t align = 1, arch_align;
 847
 848	if (type & IORESOURCE_MEM)
 849		align = PCI_P2P_DEFAULT_MEM_ALIGN;
 850	else if (type & IORESOURCE_IO) {
 851		/*
 852		 * Per spec, I/O windows are 4K-aligned, but some bridges have
 853		 * an extension to support 1K alignment.
 854		 */
 855		if (bus->self && bus->self->io_window_1k)
 856			align = PCI_P2P_DEFAULT_IO_ALIGN_1K;
 857		else
 858			align = PCI_P2P_DEFAULT_IO_ALIGN;
 859	}
 860
 861	arch_align = pcibios_window_alignment(bus, type);
 862	return max(align, arch_align);
 863}
 864
 865/**
 866 * pbus_size_io() - Size the I/O window of a given bus
 867 *
 868 * @bus:		The bus
 869 * @min_size:		The minimum I/O window that must be allocated
 870 * @add_size:		Additional optional I/O window
 871 * @realloc_head:	Track the additional I/O window on this list
 872 *
 873 * Sizing the I/O windows of the PCI-PCI bridge is trivial, since these
 874 * windows have 1K or 4K granularity and the I/O ranges of non-bridge PCI
 875 * devices are limited to 256 bytes.  We must be careful with the ISA
 876 * aliasing though.
 877 */
 878static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
 879			 resource_size_t add_size,
 880			 struct list_head *realloc_head)
 881{
 882	struct pci_dev *dev;
 883	struct resource *b_res = find_bus_resource_of_type(bus, IORESOURCE_IO,
 884							   IORESOURCE_IO);
 885	resource_size_t size = 0, size0 = 0, size1 = 0;
 886	resource_size_t children_add_size = 0;
 887	resource_size_t min_align, align;
 888
 889	if (!b_res)
 890		return;
 891
 892	/* If resource is already assigned, nothing more to do */
 893	if (b_res->parent)
 894		return;
 895
 896	min_align = window_alignment(bus, IORESOURCE_IO);
 897	list_for_each_entry(dev, &bus->devices, bus_list) {
 898		int i;
 899
 900		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
 901			struct resource *r = &dev->resource[i];
 902			unsigned long r_size;
 903
 904			if (r->parent || !(r->flags & IORESOURCE_IO))
 905				continue;
 906			r_size = resource_size(r);
 907
 908			if (r_size < 0x400)
 909				/* Might be re-aligned for ISA */
 910				size += r_size;
 911			else
 912				size1 += r_size;
 913
 914			align = pci_resource_alignment(dev, r);
 915			if (align > min_align)
 916				min_align = align;
 917
 918			if (realloc_head)
 919				children_add_size += get_res_add_size(realloc_head, r);
 920		}
 921	}
 922
 923	size0 = calculate_iosize(size, min_size, size1, 0, 0,
 924			resource_size(b_res), min_align);
 925	size1 = (!realloc_head || (realloc_head && !add_size && !children_add_size)) ? size0 :
 926		calculate_iosize(size, min_size, size1, add_size, children_add_size,
 
 
 927			resource_size(b_res), min_align);
 928	if (!size0 && !size1) {
 929		if (bus->self && (b_res->start || b_res->end))
 930			pci_info(bus->self, "disabling bridge window %pR to %pR (unused)\n",
 931				 b_res, &bus->busn_res);
 932		b_res->flags = 0;
 933		return;
 934	}
 935
 936	b_res->start = min_align;
 937	b_res->end = b_res->start + size0 - 1;
 938	b_res->flags |= IORESOURCE_STARTALIGN;
 939	if (bus->self && size1 > size0 && realloc_head) {
 940		add_to_list(realloc_head, bus->self, b_res, size1-size0,
 941			    min_align);
 942		pci_info(bus->self, "bridge window %pR to %pR add_size %llx\n",
 943			 b_res, &bus->busn_res,
 944			 (unsigned long long) size1 - size0);
 945	}
 946}
 947
 948static inline resource_size_t calculate_mem_align(resource_size_t *aligns,
 949						  int max_order)
 950{
 951	resource_size_t align = 0;
 952	resource_size_t min_align = 0;
 953	int order;
 954
 955	for (order = 0; order <= max_order; order++) {
 956		resource_size_t align1 = 1;
 957
 958		align1 <<= (order + 20);
 959
 960		if (!align)
 961			min_align = align1;
 962		else if (ALIGN(align + min_align, min_align) < align1)
 963			min_align = align1 >> 1;
 964		align += aligns[order];
 965	}
 966
 967	return min_align;
 968}
 969
 970/**
 971 * pbus_size_mem() - Size the memory window of a given bus
 972 *
 973 * @bus:		The bus
 974 * @mask:		Mask the resource flag, then compare it with type
 975 * @type:		The type of free resource from bridge
 976 * @type2:		Second match type
 977 * @type3:		Third match type
 978 * @min_size:		The minimum memory window that must be allocated
 979 * @add_size:		Additional optional memory window
 980 * @realloc_head:	Track the additional memory window on this list
 981 *
 982 * Calculate the size of the bus and minimal alignment which guarantees
 983 * that all child resources fit in this size.
 984 *
 985 * Return -ENOSPC if there's no available bus resource of the desired
 986 * type.  Otherwise, set the bus resource start/end to indicate the
 987 * required size, add things to realloc_head (if supplied), and return 0.
 988 */
 989static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
 990			 unsigned long type, unsigned long type2,
 991			 unsigned long type3, resource_size_t min_size,
 992			 resource_size_t add_size,
 993			 struct list_head *realloc_head)
 994{
 995	struct pci_dev *dev;
 996	resource_size_t min_align, align, size, size0, size1;
 997	resource_size_t aligns[18]; /* Alignments from 1MB to 128GB */
 998	int order, max_order;
 999	struct resource *b_res = find_bus_resource_of_type(bus,
1000					mask | IORESOURCE_PREFETCH, type);
1001	resource_size_t children_add_size = 0;
1002	resource_size_t children_add_align = 0;
1003	resource_size_t add_align = 0;
1004
1005	if (!b_res)
1006		return -ENOSPC;
1007
1008	/* If resource is already assigned, nothing more to do */
1009	if (b_res->parent)
1010		return 0;
1011
1012	memset(aligns, 0, sizeof(aligns));
1013	max_order = 0;
1014	size = 0;
1015
1016	list_for_each_entry(dev, &bus->devices, bus_list) {
1017		int i;
1018
1019		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
1020			struct resource *r = &dev->resource[i];
1021			resource_size_t r_size;
1022
1023			if (r->parent || (r->flags & IORESOURCE_PCI_FIXED) ||
1024			    ((r->flags & mask) != type &&
1025			     (r->flags & mask) != type2 &&
1026			     (r->flags & mask) != type3))
1027				continue;
1028			r_size = resource_size(r);
1029#ifdef CONFIG_PCI_IOV
1030			/* Put SRIOV requested res to the optional list */
1031			if (realloc_head && i >= PCI_IOV_RESOURCES &&
1032					i <= PCI_IOV_RESOURCE_END) {
1033				add_align = max(pci_resource_alignment(dev, r), add_align);
1034				r->end = r->start - 1;
1035				add_to_list(realloc_head, dev, r, r_size, 0 /* Don't care */);
1036				children_add_size += r_size;
1037				continue;
1038			}
1039#endif
1040			/*
1041			 * aligns[0] is for 1MB (since bridge memory
1042			 * windows are always at least 1MB aligned), so
1043			 * keep "order" from being negative for smaller
1044			 * resources.
1045			 */
1046			align = pci_resource_alignment(dev, r);
1047			order = __ffs(align) - 20;
1048			if (order < 0)
1049				order = 0;
1050			if (order >= ARRAY_SIZE(aligns)) {
1051				pci_warn(dev, "disabling BAR %d: %pR (bad alignment %#llx)\n",
1052					 i, r, (unsigned long long) align);
1053				r->flags = 0;
1054				continue;
1055			}
1056			size += max(r_size, align);
1057			/*
1058			 * Exclude ranges with size > align from calculation of
1059			 * the alignment.
1060			 */
1061			if (r_size <= align)
1062				aligns[order] += align;
1063			if (order > max_order)
1064				max_order = order;
1065
1066			if (realloc_head) {
1067				children_add_size += get_res_add_size(realloc_head, r);
1068				children_add_align = get_res_add_align(realloc_head, r);
1069				add_align = max(add_align, children_add_align);
1070			}
1071		}
1072	}
1073
1074	min_align = calculate_mem_align(aligns, max_order);
1075	min_align = max(min_align, window_alignment(bus, b_res->flags));
1076	size0 = calculate_memsize(size, min_size, 0, 0, resource_size(b_res), min_align);
1077	add_align = max(min_align, add_align);
1078	size1 = (!realloc_head || (realloc_head && !add_size && !children_add_size)) ? size0 :
1079		calculate_memsize(size, min_size, add_size, children_add_size,
 
 
1080				resource_size(b_res), add_align);
1081	if (!size0 && !size1) {
1082		if (bus->self && (b_res->start || b_res->end))
1083			pci_info(bus->self, "disabling bridge window %pR to %pR (unused)\n",
1084				 b_res, &bus->busn_res);
1085		b_res->flags = 0;
1086		return 0;
1087	}
1088	b_res->start = min_align;
1089	b_res->end = size0 + min_align - 1;
1090	b_res->flags |= IORESOURCE_STARTALIGN;
1091	if (bus->self && size1 > size0 && realloc_head) {
1092		add_to_list(realloc_head, bus->self, b_res, size1-size0, add_align);
1093		pci_info(bus->self, "bridge window %pR to %pR add_size %llx add_align %llx\n",
1094			   b_res, &bus->busn_res,
1095			   (unsigned long long) (size1 - size0),
1096			   (unsigned long long) add_align);
1097	}
1098	return 0;
1099}
1100
1101unsigned long pci_cardbus_resource_alignment(struct resource *res)
1102{
1103	if (res->flags & IORESOURCE_IO)
1104		return pci_cardbus_io_size;
1105	if (res->flags & IORESOURCE_MEM)
1106		return pci_cardbus_mem_size;
1107	return 0;
1108}
1109
1110static void pci_bus_size_cardbus(struct pci_bus *bus,
1111				 struct list_head *realloc_head)
1112{
1113	struct pci_dev *bridge = bus->self;
1114	struct resource *b_res;
1115	resource_size_t b_res_3_size = pci_cardbus_mem_size * 2;
1116	u16 ctrl;
1117
1118	b_res = &bridge->resource[PCI_CB_BRIDGE_IO_0_WINDOW];
1119	if (b_res->parent)
1120		goto handle_b_res_1;
1121	/*
1122	 * Reserve some resources for CardBus.  We reserve a fixed amount
1123	 * of bus space for CardBus bridges.
1124	 */
1125	b_res->start = pci_cardbus_io_size;
1126	b_res->end = b_res->start + pci_cardbus_io_size - 1;
1127	b_res->flags |= IORESOURCE_IO | IORESOURCE_STARTALIGN;
1128	if (realloc_head) {
1129		b_res->end -= pci_cardbus_io_size;
1130		add_to_list(realloc_head, bridge, b_res, pci_cardbus_io_size,
1131			    pci_cardbus_io_size);
1132	}
1133
1134handle_b_res_1:
1135	b_res = &bridge->resource[PCI_CB_BRIDGE_IO_1_WINDOW];
1136	if (b_res->parent)
1137		goto handle_b_res_2;
1138	b_res->start = pci_cardbus_io_size;
1139	b_res->end = b_res->start + pci_cardbus_io_size - 1;
1140	b_res->flags |= IORESOURCE_IO | IORESOURCE_STARTALIGN;
1141	if (realloc_head) {
1142		b_res->end -= pci_cardbus_io_size;
1143		add_to_list(realloc_head, bridge, b_res, pci_cardbus_io_size,
1144			    pci_cardbus_io_size);
1145	}
1146
1147handle_b_res_2:
1148	/* MEM1 must not be pref MMIO */
1149	pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
1150	if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM1) {
1151		ctrl &= ~PCI_CB_BRIDGE_CTL_PREFETCH_MEM1;
1152		pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
1153		pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
1154	}
1155
1156	/* Check whether prefetchable memory is supported by this bridge. */
 
 
 
1157	pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
1158	if (!(ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0)) {
1159		ctrl |= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0;
1160		pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
1161		pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
1162	}
1163
1164	b_res = &bridge->resource[PCI_CB_BRIDGE_MEM_0_WINDOW];
1165	if (b_res->parent)
1166		goto handle_b_res_3;
1167	/*
1168	 * If we have prefetchable memory support, allocate two regions.
1169	 * Otherwise, allocate one region of twice the size.
 
1170	 */
1171	if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) {
1172		b_res->start = pci_cardbus_mem_size;
1173		b_res->end = b_res->start + pci_cardbus_mem_size - 1;
1174		b_res->flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH |
1175				    IORESOURCE_STARTALIGN;
1176		if (realloc_head) {
1177			b_res->end -= pci_cardbus_mem_size;
1178			add_to_list(realloc_head, bridge, b_res,
1179				    pci_cardbus_mem_size, pci_cardbus_mem_size);
1180		}
1181
1182		/* Reduce that to half */
1183		b_res_3_size = pci_cardbus_mem_size;
1184	}
1185
1186handle_b_res_3:
1187	b_res = &bridge->resource[PCI_CB_BRIDGE_MEM_1_WINDOW];
1188	if (b_res->parent)
1189		goto handle_done;
1190	b_res->start = pci_cardbus_mem_size;
1191	b_res->end = b_res->start + b_res_3_size - 1;
1192	b_res->flags |= IORESOURCE_MEM | IORESOURCE_STARTALIGN;
1193	if (realloc_head) {
1194		b_res->end -= b_res_3_size;
1195		add_to_list(realloc_head, bridge, b_res, b_res_3_size,
1196			    pci_cardbus_mem_size);
1197	}
1198
1199handle_done:
1200	;
1201}
1202
1203void __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head)
1204{
1205	struct pci_dev *dev;
1206	unsigned long mask, prefmask, type2 = 0, type3 = 0;
1207	resource_size_t additional_io_size = 0, additional_mmio_size = 0,
1208			additional_mmio_pref_size = 0;
1209	struct resource *pref;
1210	struct pci_host_bridge *host;
1211	int hdr_type, i, ret;
1212
1213	list_for_each_entry(dev, &bus->devices, bus_list) {
1214		struct pci_bus *b = dev->subordinate;
1215		if (!b)
1216			continue;
1217
1218		switch (dev->hdr_type) {
1219		case PCI_HEADER_TYPE_CARDBUS:
1220			pci_bus_size_cardbus(b, realloc_head);
1221			break;
1222
1223		case PCI_HEADER_TYPE_BRIDGE:
1224		default:
1225			__pci_bus_size_bridges(b, realloc_head);
1226			break;
1227		}
1228	}
1229
1230	/* The root bus? */
1231	if (pci_is_root_bus(bus)) {
1232		host = to_pci_host_bridge(bus->bridge);
1233		if (!host->size_windows)
1234			return;
1235		pci_bus_for_each_resource(bus, pref, i)
1236			if (pref && (pref->flags & IORESOURCE_PREFETCH))
1237				break;
1238		hdr_type = -1;	/* Intentionally invalid - not a PCI device. */
1239	} else {
1240		pref = &bus->self->resource[PCI_BRIDGE_PREF_MEM_WINDOW];
1241		hdr_type = bus->self->hdr_type;
1242	}
1243
1244	switch (hdr_type) {
1245	case PCI_HEADER_TYPE_CARDBUS:
1246		/* Don't size CardBuses yet */
1247		break;
1248
1249	case PCI_HEADER_TYPE_BRIDGE:
1250		pci_bridge_check_ranges(bus);
1251		if (bus->self->is_hotplug_bridge) {
1252			additional_io_size  = pci_hotplug_io_size;
1253			additional_mmio_size = pci_hotplug_mmio_size;
1254			additional_mmio_pref_size = pci_hotplug_mmio_pref_size;
1255		}
1256		fallthrough;
1257	default:
1258		pbus_size_io(bus, realloc_head ? 0 : additional_io_size,
1259			     additional_io_size, realloc_head);
1260
1261		/*
1262		 * If there's a 64-bit prefetchable MMIO window, compute
1263		 * the size required to put all 64-bit prefetchable
1264		 * resources in it.
1265		 */
 
1266		mask = IORESOURCE_MEM;
1267		prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH;
1268		if (pref && (pref->flags & IORESOURCE_MEM_64)) {
1269			prefmask |= IORESOURCE_MEM_64;
1270			ret = pbus_size_mem(bus, prefmask, prefmask,
1271				prefmask, prefmask,
1272				realloc_head ? 0 : additional_mmio_pref_size,
1273				additional_mmio_pref_size, realloc_head);
1274
1275			/*
1276			 * If successful, all non-prefetchable resources
1277			 * and any 32-bit prefetchable resources will go in
1278			 * the non-prefetchable window.
1279			 */
1280			if (ret == 0) {
1281				mask = prefmask;
1282				type2 = prefmask & ~IORESOURCE_MEM_64;
1283				type3 = prefmask & ~IORESOURCE_PREFETCH;
1284			}
1285		}
1286
1287		/*
1288		 * If there is no 64-bit prefetchable window, compute the
1289		 * size required to put all prefetchable resources in the
1290		 * 32-bit prefetchable window (if there is one).
1291		 */
1292		if (!type2) {
1293			prefmask &= ~IORESOURCE_MEM_64;
1294			ret = pbus_size_mem(bus, prefmask, prefmask,
1295				prefmask, prefmask,
1296				realloc_head ? 0 : additional_mmio_pref_size,
1297				additional_mmio_pref_size, realloc_head);
1298
1299			/*
1300			 * If successful, only non-prefetchable resources
1301			 * will go in the non-prefetchable window.
1302			 */
1303			if (ret == 0)
1304				mask = prefmask;
1305			else
1306				additional_mmio_size += additional_mmio_pref_size;
1307
1308			type2 = type3 = IORESOURCE_MEM;
1309		}
1310
1311		/*
1312		 * Compute the size required to put everything else in the
1313		 * non-prefetchable window. This includes:
1314		 *
1315		 *   - all non-prefetchable resources
1316		 *   - 32-bit prefetchable resources if there's a 64-bit
1317		 *     prefetchable window or no prefetchable window at all
1318		 *   - 64-bit prefetchable resources if there's no prefetchable
1319		 *     window at all
1320		 *
1321		 * Note that the strategy in __pci_assign_resource() must match
1322		 * that used here. Specifically, we cannot put a 32-bit
1323		 * prefetchable resource in a 64-bit prefetchable window.
 
1324		 */
1325		pbus_size_mem(bus, mask, IORESOURCE_MEM, type2, type3,
1326			      realloc_head ? 0 : additional_mmio_size,
1327			      additional_mmio_size, realloc_head);
1328		break;
1329	}
1330}
1331
1332void pci_bus_size_bridges(struct pci_bus *bus)
1333{
1334	__pci_bus_size_bridges(bus, NULL);
1335}
1336EXPORT_SYMBOL(pci_bus_size_bridges);
1337
1338static void assign_fixed_resource_on_bus(struct pci_bus *b, struct resource *r)
1339{
1340	int i;
1341	struct resource *parent_r;
1342	unsigned long mask = IORESOURCE_IO | IORESOURCE_MEM |
1343			     IORESOURCE_PREFETCH;
1344
1345	pci_bus_for_each_resource(b, parent_r, i) {
1346		if (!parent_r)
1347			continue;
1348
1349		if ((r->flags & mask) == (parent_r->flags & mask) &&
1350		    resource_contains(parent_r, r))
1351			request_resource(parent_r, r);
1352	}
1353}
1354
1355/*
1356 * Try to assign any resources marked as IORESOURCE_PCI_FIXED, as they are
1357 * skipped by pbus_assign_resources_sorted().
1358 */
1359static void pdev_assign_fixed_resources(struct pci_dev *dev)
1360{
1361	int i;
1362
1363	for (i = 0; i <  PCI_NUM_RESOURCES; i++) {
1364		struct pci_bus *b;
1365		struct resource *r = &dev->resource[i];
1366
1367		if (r->parent || !(r->flags & IORESOURCE_PCI_FIXED) ||
1368		    !(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
1369			continue;
1370
1371		b = dev->bus;
1372		while (b && !r->parent) {
1373			assign_fixed_resource_on_bus(b, r);
1374			b = b->parent;
1375		}
1376	}
1377}
1378
1379void __pci_bus_assign_resources(const struct pci_bus *bus,
1380				struct list_head *realloc_head,
1381				struct list_head *fail_head)
1382{
1383	struct pci_bus *b;
1384	struct pci_dev *dev;
1385
1386	pbus_assign_resources_sorted(bus, realloc_head, fail_head);
1387
1388	list_for_each_entry(dev, &bus->devices, bus_list) {
1389		pdev_assign_fixed_resources(dev);
1390
1391		b = dev->subordinate;
1392		if (!b)
1393			continue;
1394
1395		__pci_bus_assign_resources(b, realloc_head, fail_head);
1396
1397		switch (dev->hdr_type) {
1398		case PCI_HEADER_TYPE_BRIDGE:
1399			if (!pci_is_enabled(dev))
1400				pci_setup_bridge(b);
1401			break;
1402
1403		case PCI_HEADER_TYPE_CARDBUS:
1404			pci_setup_cardbus(b);
1405			break;
1406
1407		default:
1408			pci_info(dev, "not setting up bridge for bus %04x:%02x\n",
1409				 pci_domain_nr(b), b->number);
1410			break;
1411		}
1412	}
1413}
1414
1415void pci_bus_assign_resources(const struct pci_bus *bus)
1416{
1417	__pci_bus_assign_resources(bus, NULL, NULL);
1418}
1419EXPORT_SYMBOL(pci_bus_assign_resources);
1420
1421static void pci_claim_device_resources(struct pci_dev *dev)
1422{
1423	int i;
1424
1425	for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
1426		struct resource *r = &dev->resource[i];
1427
1428		if (!r->flags || r->parent)
1429			continue;
1430
1431		pci_claim_resource(dev, i);
1432	}
1433}
1434
1435static void pci_claim_bridge_resources(struct pci_dev *dev)
1436{
1437	int i;
1438
1439	for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) {
1440		struct resource *r = &dev->resource[i];
1441
1442		if (!r->flags || r->parent)
1443			continue;
1444
1445		pci_claim_bridge_resource(dev, i);
1446	}
1447}
1448
1449static void pci_bus_allocate_dev_resources(struct pci_bus *b)
1450{
1451	struct pci_dev *dev;
1452	struct pci_bus *child;
1453
1454	list_for_each_entry(dev, &b->devices, bus_list) {
1455		pci_claim_device_resources(dev);
1456
1457		child = dev->subordinate;
1458		if (child)
1459			pci_bus_allocate_dev_resources(child);
1460	}
1461}
1462
1463static void pci_bus_allocate_resources(struct pci_bus *b)
1464{
1465	struct pci_bus *child;
1466
1467	/*
1468	 * Carry out a depth-first search on the PCI bus tree to allocate
1469	 * bridge apertures.  Read the programmed bridge bases and
1470	 * recursively claim the respective bridge resources.
1471	 */
1472	if (b->self) {
1473		pci_read_bridge_bases(b);
1474		pci_claim_bridge_resources(b->self);
1475	}
1476
1477	list_for_each_entry(child, &b->children, node)
1478		pci_bus_allocate_resources(child);
1479}
1480
1481void pci_bus_claim_resources(struct pci_bus *b)
1482{
1483	pci_bus_allocate_resources(b);
1484	pci_bus_allocate_dev_resources(b);
1485}
1486EXPORT_SYMBOL(pci_bus_claim_resources);
1487
1488static void __pci_bridge_assign_resources(const struct pci_dev *bridge,
1489					  struct list_head *add_head,
1490					  struct list_head *fail_head)
1491{
1492	struct pci_bus *b;
1493
1494	pdev_assign_resources_sorted((struct pci_dev *)bridge,
1495					 add_head, fail_head);
1496
1497	b = bridge->subordinate;
1498	if (!b)
1499		return;
1500
1501	__pci_bus_assign_resources(b, add_head, fail_head);
1502
1503	switch (bridge->class >> 8) {
1504	case PCI_CLASS_BRIDGE_PCI:
1505		pci_setup_bridge(b);
1506		break;
1507
1508	case PCI_CLASS_BRIDGE_CARDBUS:
1509		pci_setup_cardbus(b);
1510		break;
1511
1512	default:
1513		pci_info(bridge, "not setting up bridge for bus %04x:%02x\n",
1514			 pci_domain_nr(b), b->number);
1515		break;
1516	}
1517}
1518
1519#define PCI_RES_TYPE_MASK \
1520	(IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH |\
1521	 IORESOURCE_MEM_64)
1522
1523static void pci_bridge_release_resources(struct pci_bus *bus,
1524					 unsigned long type)
1525{
1526	struct pci_dev *dev = bus->self;
1527	struct resource *r;
 
 
1528	unsigned old_flags = 0;
1529	struct resource *b_res;
1530	int idx = 1;
1531
1532	b_res = &dev->resource[PCI_BRIDGE_RESOURCES];
1533
1534	/*
1535	 * 1. If IO port assignment fails, release bridge IO port.
1536	 * 2. If non pref MMIO assignment fails, release bridge nonpref MMIO.
1537	 * 3. If 64bit pref MMIO assignment fails, and bridge pref is 64bit,
1538	 *    release bridge pref MMIO.
1539	 * 4. If pref MMIO assignment fails, and bridge pref is 32bit,
1540	 *    release bridge pref MMIO.
1541	 * 5. If pref MMIO assignment fails, and bridge pref is not
1542	 *    assigned, release bridge nonpref MMIO.
 
 
1543	 */
1544	if (type & IORESOURCE_IO)
1545		idx = 0;
1546	else if (!(type & IORESOURCE_PREFETCH))
1547		idx = 1;
1548	else if ((type & IORESOURCE_MEM_64) &&
1549		 (b_res[2].flags & IORESOURCE_MEM_64))
1550		idx = 2;
1551	else if (!(b_res[2].flags & IORESOURCE_MEM_64) &&
1552		 (b_res[2].flags & IORESOURCE_PREFETCH))
1553		idx = 2;
1554	else
1555		idx = 1;
1556
1557	r = &b_res[idx];
1558
1559	if (!r->parent)
1560		return;
1561
1562	/* If there are children, release them all */
 
 
 
1563	release_child_resources(r);
1564	if (!release_resource(r)) {
1565		type = old_flags = r->flags & PCI_RES_TYPE_MASK;
1566		pci_info(dev, "resource %d %pR released\n",
1567			 PCI_BRIDGE_RESOURCES + idx, r);
1568		/* Keep the old size */
1569		r->end = resource_size(r) - 1;
1570		r->start = 0;
1571		r->flags = 0;
1572
1573		/* Avoiding touch the one without PREF */
1574		if (type & IORESOURCE_PREFETCH)
1575			type = IORESOURCE_PREFETCH;
1576		__pci_setup_bridge(bus, type);
1577		/* For next child res under same bridge */
1578		r->flags = old_flags;
1579	}
1580}
1581
1582enum release_type {
1583	leaf_only,
1584	whole_subtree,
1585};
1586
1587/*
1588 * Try to release PCI bridge resources from leaf bridge, so we can allocate
1589 * a larger window later.
1590 */
1591static void pci_bus_release_bridge_resources(struct pci_bus *bus,
1592					     unsigned long type,
1593					     enum release_type rel_type)
1594{
1595	struct pci_dev *dev;
1596	bool is_leaf_bridge = true;
1597
1598	list_for_each_entry(dev, &bus->devices, bus_list) {
1599		struct pci_bus *b = dev->subordinate;
1600		if (!b)
1601			continue;
1602
1603		is_leaf_bridge = false;
1604
1605		if ((dev->class >> 8) != PCI_CLASS_BRIDGE_PCI)
1606			continue;
1607
1608		if (rel_type == whole_subtree)
1609			pci_bus_release_bridge_resources(b, type,
1610						 whole_subtree);
1611	}
1612
1613	if (pci_is_root_bus(bus))
1614		return;
1615
1616	if ((bus->self->class >> 8) != PCI_CLASS_BRIDGE_PCI)
1617		return;
1618
1619	if ((rel_type == whole_subtree) || is_leaf_bridge)
1620		pci_bridge_release_resources(bus, type);
1621}
1622
1623static void pci_bus_dump_res(struct pci_bus *bus)
1624{
1625	struct resource *res;
1626	int i;
1627
1628	pci_bus_for_each_resource(bus, res, i) {
1629		if (!res || !res->end || !res->flags)
1630			continue;
1631
1632		dev_info(&bus->dev, "resource %d %pR\n", i, res);
1633	}
1634}
1635
1636static void pci_bus_dump_resources(struct pci_bus *bus)
1637{
1638	struct pci_bus *b;
1639	struct pci_dev *dev;
1640
1641
1642	pci_bus_dump_res(bus);
1643
1644	list_for_each_entry(dev, &bus->devices, bus_list) {
1645		b = dev->subordinate;
1646		if (!b)
1647			continue;
1648
1649		pci_bus_dump_resources(b);
1650	}
1651}
1652
1653static int pci_bus_get_depth(struct pci_bus *bus)
1654{
1655	int depth = 0;
1656	struct pci_bus *child_bus;
1657
1658	list_for_each_entry(child_bus, &bus->children, node) {
1659		int ret;
1660
1661		ret = pci_bus_get_depth(child_bus);
1662		if (ret + 1 > depth)
1663			depth = ret + 1;
1664	}
1665
1666	return depth;
1667}
1668
1669/*
1670 * -1: undefined, will auto detect later
1671 *  0: disabled by user
1672 *  1: disabled by auto detect
1673 *  2: enabled by user
1674 *  3: enabled by auto detect
1675 */
1676enum enable_type {
1677	undefined = -1,
1678	user_disabled,
1679	auto_disabled,
1680	user_enabled,
1681	auto_enabled,
1682};
1683
1684static enum enable_type pci_realloc_enable = undefined;
1685void __init pci_realloc_get_opt(char *str)
1686{
1687	if (!strncmp(str, "off", 3))
1688		pci_realloc_enable = user_disabled;
1689	else if (!strncmp(str, "on", 2))
1690		pci_realloc_enable = user_enabled;
1691}
1692static bool pci_realloc_enabled(enum enable_type enable)
1693{
1694	return enable >= user_enabled;
1695}
1696
1697#if defined(CONFIG_PCI_IOV) && defined(CONFIG_PCI_REALLOC_ENABLE_AUTO)
1698static int iov_resources_unassigned(struct pci_dev *dev, void *data)
1699{
1700	int i;
1701	bool *unassigned = data;
1702
1703	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
1704		struct resource *r = &dev->resource[i + PCI_IOV_RESOURCES];
1705		struct pci_bus_region region;
1706
1707		/* Not assigned or rejected by kernel? */
1708		if (!r->flags)
1709			continue;
1710
1711		pcibios_resource_to_bus(dev->bus, &region, r);
1712		if (!region.start) {
1713			*unassigned = true;
1714			return 1; /* Return early from pci_walk_bus() */
1715		}
1716	}
1717
1718	return 0;
1719}
1720
1721static enum enable_type pci_realloc_detect(struct pci_bus *bus,
1722					   enum enable_type enable_local)
1723{
1724	bool unassigned = false;
1725	struct pci_host_bridge *host;
1726
1727	if (enable_local != undefined)
1728		return enable_local;
1729
1730	host = pci_find_host_bridge(bus);
1731	if (host->preserve_config)
1732		return auto_disabled;
1733
1734	pci_walk_bus(bus, iov_resources_unassigned, &unassigned);
1735	if (unassigned)
1736		return auto_enabled;
1737
1738	return enable_local;
1739}
1740#else
1741static enum enable_type pci_realloc_detect(struct pci_bus *bus,
1742					   enum enable_type enable_local)
1743{
1744	return enable_local;
1745}
1746#endif
1747
1748/*
1749 * First try will not touch PCI bridge res.
1750 * Second and later try will clear small leaf bridge res.
1751 * Will stop till to the max depth if can not find good one.
1752 */
1753void pci_assign_unassigned_root_bus_resources(struct pci_bus *bus)
1754{
1755	LIST_HEAD(realloc_head);
1756	/* List of resources that want additional resources */
1757	struct list_head *add_list = NULL;
1758	int tried_times = 0;
1759	enum release_type rel_type = leaf_only;
1760	LIST_HEAD(fail_head);
1761	struct pci_dev_resource *fail_res;
 
 
1762	int pci_try_num = 1;
1763	enum enable_type enable_local;
1764
1765	/* Don't realloc if asked to do so */
1766	enable_local = pci_realloc_detect(bus, pci_realloc_enable);
1767	if (pci_realloc_enabled(enable_local)) {
1768		int max_depth = pci_bus_get_depth(bus);
1769
1770		pci_try_num = max_depth + 1;
1771		dev_info(&bus->dev, "max bus depth: %d pci_try_num: %d\n",
1772			 max_depth, pci_try_num);
 
1773	}
1774
1775again:
1776	/*
1777	 * Last try will use add_list, otherwise will try good to have as must
1778	 * have, so can realloc parent bridge resource
1779	 */
1780	if (tried_times + 1 == pci_try_num)
1781		add_list = &realloc_head;
1782	/*
1783	 * Depth first, calculate sizes and alignments of all subordinate buses.
1784	 */
1785	__pci_bus_size_bridges(bus, add_list);
1786
1787	/* Depth last, allocate resources and update the hardware. */
1788	__pci_bus_assign_resources(bus, add_list, &fail_head);
1789	if (add_list)
1790		BUG_ON(!list_empty(add_list));
1791	tried_times++;
1792
1793	/* Any device complain? */
1794	if (list_empty(&fail_head))
1795		goto dump;
1796
1797	if (tried_times >= pci_try_num) {
1798		if (enable_local == undefined)
1799			dev_info(&bus->dev, "Some PCI device resources are unassigned, try booting with pci=realloc\n");
1800		else if (enable_local == auto_enabled)
1801			dev_info(&bus->dev, "Automatically enabled pci realloc, if you have problem, try booting with pci=realloc=off\n");
1802
1803		free_list(&fail_head);
1804		goto dump;
1805	}
1806
1807	dev_info(&bus->dev, "No. %d try to assign unassigned res\n",
1808		 tried_times + 1);
1809
1810	/* Third times and later will not check if it is leaf */
1811	if ((tried_times + 1) > 2)
1812		rel_type = whole_subtree;
1813
1814	/*
1815	 * Try to release leaf bridge's resources that doesn't fit resource of
1816	 * child device under that bridge.
1817	 */
1818	list_for_each_entry(fail_res, &fail_head, list)
1819		pci_bus_release_bridge_resources(fail_res->dev->bus,
1820						 fail_res->flags & PCI_RES_TYPE_MASK,
1821						 rel_type);
1822
1823	/* Restore size and flags */
1824	list_for_each_entry(fail_res, &fail_head, list) {
1825		struct resource *res = fail_res->res;
1826		int idx;
1827
1828		res->start = fail_res->start;
1829		res->end = fail_res->end;
1830		res->flags = fail_res->flags;
1831
1832		if (pci_is_bridge(fail_res->dev)) {
1833			idx = res - &fail_res->dev->resource[0];
1834			if (idx >= PCI_BRIDGE_RESOURCES &&
1835			    idx <= PCI_BRIDGE_RESOURCE_END)
1836				res->flags = 0;
1837		}
1838	}
1839	free_list(&fail_head);
1840
1841	goto again;
1842
1843dump:
1844	/* Dump the resource on buses */
1845	pci_bus_dump_resources(bus);
1846}
1847
1848void __init pci_assign_unassigned_resources(void)
1849{
1850	struct pci_bus *root_bus;
1851
1852	list_for_each_entry(root_bus, &pci_root_buses, node) {
1853		pci_assign_unassigned_root_bus_resources(root_bus);
1854
1855		/* Make sure the root bridge has a companion ACPI device */
1856		if (ACPI_HANDLE(root_bus->bridge))
1857			acpi_ioapic_add(ACPI_HANDLE(root_bus->bridge));
1858	}
1859}
1860
1861static void adjust_bridge_window(struct pci_dev *bridge, struct resource *res,
1862				 struct list_head *add_list,
1863				 resource_size_t new_size)
1864{
1865	resource_size_t add_size, size = resource_size(res);
1866
1867	if (res->parent)
1868		return;
1869
1870	if (!new_size)
1871		return;
1872
1873	if (new_size > size) {
1874		add_size = new_size - size;
1875		pci_dbg(bridge, "bridge window %pR extended by %pa\n", res,
1876			&add_size);
1877	} else if (new_size < size) {
1878		add_size = size - new_size;
1879		pci_dbg(bridge, "bridge window %pR shrunken by %pa\n", res,
1880			&add_size);
1881	}
1882
1883	res->end = res->start + new_size - 1;
1884	remove_from_list(add_list, res);
1885}
1886
1887static void pci_bus_distribute_available_resources(struct pci_bus *bus,
1888					    struct list_head *add_list,
1889					    struct resource io,
1890					    struct resource mmio,
1891					    struct resource mmio_pref)
1892{
1893	unsigned int normal_bridges = 0, hotplug_bridges = 0;
1894	struct resource *io_res, *mmio_res, *mmio_pref_res;
1895	struct pci_dev *dev, *bridge = bus->self;
1896	resource_size_t io_per_hp, mmio_per_hp, mmio_pref_per_hp, align;
1897
1898	io_res = &bridge->resource[PCI_BRIDGE_IO_WINDOW];
1899	mmio_res = &bridge->resource[PCI_BRIDGE_MEM_WINDOW];
1900	mmio_pref_res = &bridge->resource[PCI_BRIDGE_PREF_MEM_WINDOW];
1901
1902	/*
1903	 * The alignment of this bridge is yet to be considered, hence it must
1904	 * be done now before extending its bridge window.
1905	 */
1906	align = pci_resource_alignment(bridge, io_res);
1907	if (!io_res->parent && align)
1908		io.start = min(ALIGN(io.start, align), io.end + 1);
1909
1910	align = pci_resource_alignment(bridge, mmio_res);
1911	if (!mmio_res->parent && align)
1912		mmio.start = min(ALIGN(mmio.start, align), mmio.end + 1);
1913
1914	align = pci_resource_alignment(bridge, mmio_pref_res);
1915	if (!mmio_pref_res->parent && align)
1916		mmio_pref.start = min(ALIGN(mmio_pref.start, align),
1917			mmio_pref.end + 1);
1918
1919	/*
1920	 * Now that we have adjusted for alignment, update the bridge window
1921	 * resources to fill as much remaining resource space as possible.
1922	 */
1923	adjust_bridge_window(bridge, io_res, add_list, resource_size(&io));
1924	adjust_bridge_window(bridge, mmio_res, add_list, resource_size(&mmio));
1925	adjust_bridge_window(bridge, mmio_pref_res, add_list,
1926			     resource_size(&mmio_pref));
1927
1928	/*
1929	 * Calculate how many hotplug bridges and normal bridges there
1930	 * are on this bus.  We will distribute the additional available
1931	 * resources between hotplug bridges.
1932	 */
1933	for_each_pci_bridge(dev, bus) {
1934		if (dev->is_hotplug_bridge)
1935			hotplug_bridges++;
1936		else
1937			normal_bridges++;
1938	}
1939
1940	/*
1941	 * There is only one bridge on the bus so it gets all available
1942	 * resources which it can then distribute to the possible hotplug
1943	 * bridges below.
1944	 */
1945	if (hotplug_bridges + normal_bridges == 1) {
1946		dev = list_first_entry(&bus->devices, struct pci_dev, bus_list);
1947		if (dev->subordinate)
1948			pci_bus_distribute_available_resources(dev->subordinate,
1949				add_list, io, mmio, mmio_pref);
1950		return;
1951	}
1952
1953	if (hotplug_bridges == 0)
1954		return;
1955
1956	/*
1957	 * Calculate the total amount of extra resource space we can
1958	 * pass to bridges below this one.  This is basically the
1959	 * extra space reduced by the minimal required space for the
1960	 * non-hotplug bridges.
1961	 */
1962	for_each_pci_bridge(dev, bus) {
1963		resource_size_t used_size;
1964		struct resource *res;
1965
1966		if (dev->is_hotplug_bridge)
1967			continue;
1968
1969		/*
1970		 * Reduce the available resource space by what the
1971		 * bridge and devices below it occupy.
1972		 */
1973		res = &dev->resource[PCI_BRIDGE_IO_WINDOW];
1974		align = pci_resource_alignment(dev, res);
1975		align = align ? ALIGN(io.start, align) - io.start : 0;
1976		used_size = align + resource_size(res);
1977		if (!res->parent)
1978			io.start = min(io.start + used_size, io.end + 1);
1979
1980		res = &dev->resource[PCI_BRIDGE_MEM_WINDOW];
1981		align = pci_resource_alignment(dev, res);
1982		align = align ? ALIGN(mmio.start, align) - mmio.start : 0;
1983		used_size = align + resource_size(res);
1984		if (!res->parent)
1985			mmio.start = min(mmio.start + used_size, mmio.end + 1);
1986
1987		res = &dev->resource[PCI_BRIDGE_PREF_MEM_WINDOW];
1988		align = pci_resource_alignment(dev, res);
1989		align = align ? ALIGN(mmio_pref.start, align) -
1990			mmio_pref.start : 0;
1991		used_size = align + resource_size(res);
1992		if (!res->parent)
1993			mmio_pref.start = min(mmio_pref.start + used_size,
1994				mmio_pref.end + 1);
1995	}
1996
1997	io_per_hp = div64_ul(resource_size(&io), hotplug_bridges);
1998	mmio_per_hp = div64_ul(resource_size(&mmio), hotplug_bridges);
1999	mmio_pref_per_hp = div64_ul(resource_size(&mmio_pref),
2000		hotplug_bridges);
2001
2002	/*
2003	 * Go over devices on this bus and distribute the remaining
2004	 * resource space between hotplug bridges.
2005	 */
2006	for_each_pci_bridge(dev, bus) {
2007		struct pci_bus *b;
2008
2009		b = dev->subordinate;
2010		if (!b || !dev->is_hotplug_bridge)
2011			continue;
2012
2013		/*
2014		 * Distribute available extra resources equally between
2015		 * hotplug-capable downstream ports taking alignment into
2016		 * account.
2017		 */
2018		io.end = io.start + io_per_hp - 1;
2019		mmio.end = mmio.start + mmio_per_hp - 1;
2020		mmio_pref.end = mmio_pref.start + mmio_pref_per_hp - 1;
2021
2022		pci_bus_distribute_available_resources(b, add_list, io, mmio,
2023						       mmio_pref);
2024
2025		io.start += io_per_hp;
2026		mmio.start += mmio_per_hp;
2027		mmio_pref.start += mmio_pref_per_hp;
2028	}
2029}
2030
2031static void pci_bridge_distribute_available_resources(struct pci_dev *bridge,
2032						     struct list_head *add_list)
2033{
2034	struct resource available_io, available_mmio, available_mmio_pref;
2035
2036	if (!bridge->is_hotplug_bridge)
2037		return;
2038
2039	/* Take the initial extra resources from the hotplug port */
2040	available_io = bridge->resource[PCI_BRIDGE_IO_WINDOW];
2041	available_mmio = bridge->resource[PCI_BRIDGE_MEM_WINDOW];
2042	available_mmio_pref = bridge->resource[PCI_BRIDGE_PREF_MEM_WINDOW];
2043
2044	pci_bus_distribute_available_resources(bridge->subordinate,
2045					       add_list, available_io,
2046					       available_mmio,
2047					       available_mmio_pref);
2048}
2049
2050void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge)
2051{
2052	struct pci_bus *parent = bridge->subordinate;
2053	/* List of resources that want additional resources */
2054	LIST_HEAD(add_list);
2055
2056	int tried_times = 0;
2057	LIST_HEAD(fail_head);
2058	struct pci_dev_resource *fail_res;
2059	int retval;
 
 
2060
2061again:
2062	__pci_bus_size_bridges(parent, &add_list);
2063
2064	/*
2065	 * Distribute remaining resources (if any) equally between hotplug
2066	 * bridges below.  This makes it possible to extend the hierarchy
2067	 * later without running out of resources.
2068	 */
2069	pci_bridge_distribute_available_resources(bridge, &add_list);
2070
2071	__pci_bridge_assign_resources(bridge, &add_list, &fail_head);
2072	BUG_ON(!list_empty(&add_list));
2073	tried_times++;
2074
2075	if (list_empty(&fail_head))
2076		goto enable_all;
2077
2078	if (tried_times >= 2) {
2079		/* Still fail, don't need to try more */
2080		free_list(&fail_head);
2081		goto enable_all;
2082	}
2083
2084	printk(KERN_DEBUG "PCI: No. %d try to assign unassigned res\n",
2085			 tried_times + 1);
2086
2087	/*
2088	 * Try to release leaf bridge's resources that aren't big enough
2089	 * to contain child device resources.
2090	 */
2091	list_for_each_entry(fail_res, &fail_head, list)
2092		pci_bus_release_bridge_resources(fail_res->dev->bus,
2093						 fail_res->flags & PCI_RES_TYPE_MASK,
2094						 whole_subtree);
2095
2096	/* Restore size and flags */
2097	list_for_each_entry(fail_res, &fail_head, list) {
2098		struct resource *res = fail_res->res;
2099		int idx;
2100
2101		res->start = fail_res->start;
2102		res->end = fail_res->end;
2103		res->flags = fail_res->flags;
2104
2105		if (pci_is_bridge(fail_res->dev)) {
2106			idx = res - &fail_res->dev->resource[0];
2107			if (idx >= PCI_BRIDGE_RESOURCES &&
2108			    idx <= PCI_BRIDGE_RESOURCE_END)
2109				res->flags = 0;
2110		}
2111	}
2112	free_list(&fail_head);
2113
2114	goto again;
2115
2116enable_all:
2117	retval = pci_reenable_device(bridge);
2118	if (retval)
2119		pci_err(bridge, "Error reenabling bridge (%d)\n", retval);
2120	pci_set_master(bridge);
2121}
2122EXPORT_SYMBOL_GPL(pci_assign_unassigned_bridge_resources);
2123
2124int pci_reassign_bridge_resources(struct pci_dev *bridge, unsigned long type)
2125{
2126	struct pci_dev_resource *dev_res;
2127	struct pci_dev *next;
2128	LIST_HEAD(saved);
2129	LIST_HEAD(added);
2130	LIST_HEAD(failed);
2131	unsigned int i;
2132	int ret;
2133
2134	down_read(&pci_bus_sem);
2135
2136	/* Walk to the root hub, releasing bridge BARs when possible */
2137	next = bridge;
2138	do {
2139		bridge = next;
2140		for (i = PCI_BRIDGE_RESOURCES; i < PCI_BRIDGE_RESOURCE_END;
2141		     i++) {
2142			struct resource *res = &bridge->resource[i];
2143
2144			if ((res->flags ^ type) & PCI_RES_TYPE_MASK)
2145				continue;
2146
2147			/* Ignore BARs which are still in use */
2148			if (res->child)
2149				continue;
2150
2151			ret = add_to_list(&saved, bridge, res, 0, 0);
2152			if (ret)
2153				goto cleanup;
2154
2155			pci_info(bridge, "BAR %d: releasing %pR\n",
2156				 i, res);
2157
2158			if (res->parent)
2159				release_resource(res);
2160			res->start = 0;
2161			res->end = 0;
2162			break;
2163		}
2164		if (i == PCI_BRIDGE_RESOURCE_END)
2165			break;
2166
2167		next = bridge->bus ? bridge->bus->self : NULL;
2168	} while (next);
2169
2170	if (list_empty(&saved)) {
2171		up_read(&pci_bus_sem);
2172		return -ENOENT;
2173	}
2174
2175	__pci_bus_size_bridges(bridge->subordinate, &added);
2176	__pci_bridge_assign_resources(bridge, &added, &failed);
2177	BUG_ON(!list_empty(&added));
2178
2179	if (!list_empty(&failed)) {
2180		ret = -ENOSPC;
2181		goto cleanup;
2182	}
2183
2184	list_for_each_entry(dev_res, &saved, list) {
2185		/* Skip the bridge we just assigned resources for */
2186		if (bridge == dev_res->dev)
2187			continue;
2188
2189		bridge = dev_res->dev;
2190		pci_setup_bridge(bridge->subordinate);
2191	}
2192
2193	free_list(&saved);
2194	up_read(&pci_bus_sem);
2195	return 0;
2196
2197cleanup:
2198	/* Restore size and flags */
2199	list_for_each_entry(dev_res, &failed, list) {
2200		struct resource *res = dev_res->res;
2201
2202		res->start = dev_res->start;
2203		res->end = dev_res->end;
2204		res->flags = dev_res->flags;
2205	}
2206	free_list(&failed);
2207
2208	/* Revert to the old configuration */
2209	list_for_each_entry(dev_res, &saved, list) {
2210		struct resource *res = dev_res->res;
2211
2212		bridge = dev_res->dev;
2213		i = res - bridge->resource;
2214
2215		res->start = dev_res->start;
2216		res->end = dev_res->end;
2217		res->flags = dev_res->flags;
2218
2219		pci_claim_resource(bridge, i);
2220		pci_setup_bridge(bridge->subordinate);
2221	}
2222	free_list(&saved);
2223	up_read(&pci_bus_sem);
2224
2225	return ret;
2226}
2227
2228void pci_assign_unassigned_bus_resources(struct pci_bus *bus)
2229{
2230	struct pci_dev *dev;
2231	/* List of resources that want additional resources */
2232	LIST_HEAD(add_list);
2233
2234	down_read(&pci_bus_sem);
2235	for_each_pci_bridge(dev, bus)
2236		if (pci_has_subordinate(dev))
2237			__pci_bus_size_bridges(dev->subordinate, &add_list);
 
2238	up_read(&pci_bus_sem);
2239	__pci_bus_assign_resources(bus, &add_list, NULL);
2240	BUG_ON(!list_empty(&add_list));
2241}
2242EXPORT_SYMBOL_GPL(pci_assign_unassigned_bus_resources);