drivers/pci/dmar.c

   1 /*
   2  * Copyright (c) 2006, Intel Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  15  * Place - Suite 330, Boston, MA 02111-1307 USA.
  16  *
  17  * Copyright (C) 2006-2008 Intel Corporation
  18  * Author: Ashok Raj <ashok.raj@intel.com>
  19  * Author: Shaohua Li <shaohua.li@intel.com>
  20  * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
  21  *
  22  * This file implements early detection/parsing of Remapping Devices
  23  * reported to OS through BIOS via DMA remapping reporting (DMAR) ACPI
  24  * tables.
  25  *
  26  * These routines are used by both DMA-remapping and Interrupt-remapping
  27  */
  28
  29 #include <linux/pci.h>
  30 #include <linux/dmar.h>
  31 #include <linux/iova.h>
  32 #include <linux/intel-iommu.h>
  33 #include <linux/timer.h>
  34 #include <linux/irq.h>
  35 #include <linux/interrupt.h>
  36 #include <linux/tboot.h>
  37 #include <linux/dmi.h>
  38
  39 #define PREFIX "DMAR: "
  40
  41 /* No locks are needed as DMA remapping hardware unit
  42  * list is constructed at boot time and hotplug of
  43  * these units are not supported by the architecture.
  44  */
  45 LIST_HEAD(dmar_drhd_units);
  46
  47 static struct acpi_table_header * __initdata dmar_tbl;
  48 static acpi_size dmar_tbl_size;
  49
  50 static void __init dmar_register_drhd_unit(struct dmar_drhd_unit *drhd)
  51 {
  52         /*
  53          * add INCLUDE_ALL at the tail, so scan the list will find it at
  54          * the very end.
  55          */
  56         if (drhd->include_all)
  57                 list_add_tail(&drhd->list, &dmar_drhd_units);
  58         else
  59                 list_add(&drhd->list, &dmar_drhd_units);
  60 }
  61
  62 static int __init dmar_parse_one_dev_scope(struct acpi_dmar_device_scope *scope,
  63                                            struct pci_dev **dev, u16 segment)
  64 {
  65         struct pci_bus *bus;
  66         struct pci_dev *pdev = NULL;
  67         struct acpi_dmar_pci_path *path;
  68         int count;
  69
  70         bus = pci_find_bus(segment, scope->bus);
  71         path = (struct acpi_dmar_pci_path *)(scope + 1);
  72         count = (scope->length - sizeof(struct acpi_dmar_device_scope))
  73                 / sizeof(struct acpi_dmar_pci_path);
  74
  75         while (count) {
  76                 if (pdev)
  77                         pci_dev_put(pdev);
  78                 /*
  79                  * Some BIOSes list non-exist devices in DMAR table, just
  80                  * ignore it
  81                  */
  82                 if (!bus) {
  83                         printk(KERN_WARNING
  84                         PREFIX "Device scope bus [%d] not found\n",
  85                         scope->bus);
  86                         break;
  87                 }
  88                 pdev = pci_get_slot(bus, PCI_DEVFN(path->dev, path->fn));
  89                 if (!pdev) {
  90                         printk(KERN_WARNING PREFIX
  91                         "Device scope device [%04x:%02x:%02x.%02x] not found\n",
  92                                 segment, bus->number, path->dev, path->fn);
  93                         break;
  94                 }
  95                 path ++;
  96                 count --;
  97                 bus = pdev->subordinate;
  98         }
  99         if (!pdev) {
 100                 printk(KERN_WARNING PREFIX
 101                 "Device scope device [%04x:%02x:%02x.%02x] not found\n",
 102                 segment, scope->bus, path->dev, path->fn);
 103                 *dev = NULL;
 104                 return 0;
 105         }
 106         if ((scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT && \
 107                         pdev->subordinate) || (scope->entry_type == \
 108                         ACPI_DMAR_SCOPE_TYPE_BRIDGE && !pdev->subordinate)) {
 109                 pci_dev_put(pdev);
 110                 printk(KERN_WARNING PREFIX
 111                         "Device scope type does not match for %s\n",
 112                          pci_name(pdev));
 113                 return -EINVAL;
 114         }
 115         *dev = pdev;
 116         return 0;
 117 }
 118
 119 static int __init dmar_parse_dev_scope(void *start, void *end, int *cnt,
 120                                        struct pci_dev ***devices, u16 segment)
 121 {
 122         struct acpi_dmar_device_scope *scope;
 123         void * tmp = start;
 124         int index;
 125         int ret;
 126
 127         *cnt = 0;
 128         while (start < end) {
 129                 scope = start;
 130                 if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT ||
 131                     scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE)
 132                         (*cnt)++;
 133                 else
 134                         printk(KERN_WARNING PREFIX
 135                                 "Unsupported device scope\n");
 136                 start += scope->length;
 137         }
 138         if (*cnt == 0)
 139                 return 0;
 140
 141         *devices = kcalloc(*cnt, sizeof(struct pci_dev *), GFP_KERNEL);
 142         if (!*devices)
 143                 return -ENOMEM;
 144
 145         start = tmp;
 146         index = 0;
 147         while (start < end) {
 148                 scope = start;
 149                 if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT ||
 150                     scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE) {
 151                         ret = dmar_parse_one_dev_scope(scope,
 152                                 &(*devices)[index], segment);
 153                         if (ret) {
 154                                 kfree(*devices);
 155                                 return ret;
 156                         }
 157                         index ++;
 158                 }
 159                 start += scope->length;
 160         }
 161
 162         return 0;
 163 }
 164
 165 /**
 166  * dmar_parse_one_drhd - parses exactly one DMA remapping hardware definition
 167  * structure which uniquely represent one DMA remapping hardware unit
 168  * present in the platform
 169  */
 170 static int __init
 171 dmar_parse_one_drhd(struct acpi_dmar_header *header)
 172 {
 173         struct acpi_dmar_hardware_unit *drhd;
 174         struct dmar_drhd_unit *dmaru;
 175         int ret = 0;
 176
 177         drhd = (struct acpi_dmar_hardware_unit *)header;
 178         dmaru = kzalloc(sizeof(*dmaru), GFP_KERNEL);
 179         if (!dmaru)
 180                 return -ENOMEM;
 181
 182         dmaru->hdr = header;
 183         dmaru->reg_base_addr = drhd->address;
 184         dmaru->segment = drhd->segment;
 185         dmaru->include_all = drhd->flags & 0x1; /* BIT0: INCLUDE_ALL */
 186
 187         ret = alloc_iommu(dmaru);
 188         if (ret) {
 189                 kfree(dmaru);
 190                 return ret;
 191         }
 192         dmar_register_drhd_unit(dmaru);
 193         return 0;
 194 }
 195
 196 static int __init dmar_parse_dev(struct dmar_drhd_unit *dmaru)
 197 {
 198         struct acpi_dmar_hardware_unit *drhd;
 199         int ret = 0;
 200
 201         drhd = (struct acpi_dmar_hardware_unit *) dmaru->hdr;
 202
 203         if (dmaru->include_all)
 204                 return 0;
 205
 206         ret = dmar_parse_dev_scope((void *)(drhd + 1),
 207                                 ((void *)drhd) + drhd->header.length,
 208                                 &dmaru->devices_cnt, &dmaru->devices,
 209                                 drhd->segment);
 210         if (ret) {
 211                 list_del(&dmaru->list);
 212                 kfree(dmaru);
 213         }
 214         return ret;
 215 }
 216
 217 #ifdef CONFIG_DMAR
 218 LIST_HEAD(dmar_rmrr_units);
 219
 220 static void __init dmar_register_rmrr_unit(struct dmar_rmrr_unit *rmrr)
 221 {
 222         list_add(&rmrr->list, &dmar_rmrr_units);
 223 }
 224
 225
 226 static int __init
 227 dmar_parse_one_rmrr(struct acpi_dmar_header *header)
 228 {
 229         struct acpi_dmar_reserved_memory *rmrr;
 230         struct dmar_rmrr_unit *rmrru;
 231
 232         rmrru = kzalloc(sizeof(*rmrru), GFP_KERNEL);
 233         if (!rmrru)
 234                 return -ENOMEM;
 235
 236         rmrru->hdr = header;
 237         rmrr = (struct acpi_dmar_reserved_memory *)header;
 238         rmrru->base_address = rmrr->base_address;
 239         rmrru->end_address = rmrr->end_address;
 240
 241         dmar_register_rmrr_unit(rmrru);
 242         return 0;
 243 }
 244
 245 static int __init
 246 rmrr_parse_dev(struct dmar_rmrr_unit *rmrru)
 247 {
 248         struct acpi_dmar_reserved_memory *rmrr;
 249         int ret;
 250
 251         rmrr = (struct acpi_dmar_reserved_memory *) rmrru->hdr;
 252         ret = dmar_parse_dev_scope((void *)(rmrr + 1),
 253                 ((void *)rmrr) + rmrr->header.length,
 254                 &rmrru->devices_cnt, &rmrru->devices, rmrr->segment);
 255
 256         if (ret || (rmrru->devices_cnt == 0)) {
 257                 list_del(&rmrru->list);
 258                 kfree(rmrru);
 259         }
 260         return ret;
 261 }
 262
 263 static LIST_HEAD(dmar_atsr_units);
 264
 265 static int __init dmar_parse_one_atsr(struct acpi_dmar_header *hdr)
 266 {
 267         struct acpi_dmar_atsr *atsr;
 268         struct dmar_atsr_unit *atsru;
 269
 270         atsr = container_of(hdr, struct acpi_dmar_atsr, header);
 271         atsru = kzalloc(sizeof(*atsru), GFP_KERNEL);
 272         if (!atsru)
 273                 return -ENOMEM;
 274
 275         atsru->hdr = hdr;
 276         atsru->include_all = atsr->flags & 0x1;
 277
 278         list_add(&atsru->list, &dmar_atsr_units);
 279
 280         return 0;
 281 }
 282
 283 static int __init atsr_parse_dev(struct dmar_atsr_unit *atsru)
 284 {
 285         int rc;
 286         struct acpi_dmar_atsr *atsr;
 287
 288         if (atsru->include_all)
 289                 return 0;
 290
 291         atsr = container_of(atsru->hdr, struct acpi_dmar_atsr, header);
 292         rc = dmar_parse_dev_scope((void *)(atsr + 1),
 293                                 (void *)atsr + atsr->header.length,
 294                                 &atsru->devices_cnt, &atsru->devices,
 295                                 atsr->segment);
 296         if (rc || !atsru->devices_cnt) {
 297                 list_del(&atsru->list);
 298                 kfree(atsru);
 299         }
 300
 301         return rc;
 302 }
 303
 304 int dmar_find_matched_atsr_unit(struct pci_dev *dev)
 305 {
 306         int i;
 307         struct pci_bus *bus;
 308         struct acpi_dmar_atsr *atsr;
 309         struct dmar_atsr_unit *atsru;
 310
 311         list_for_each_entry(atsru, &dmar_atsr_units, list) {
 312                 atsr = container_of(atsru->hdr, struct acpi_dmar_atsr, header);
 313                 if (atsr->segment == pci_domain_nr(dev->bus))
 314                         goto found;
 315         }
 316
 317         return 0;
 318
 319 found:
 320         for (bus = dev->bus; bus; bus = bus->parent) {
 321                 struct pci_dev *bridge = bus->self;
 322
 323                 if (!bridge || !bridge->is_pcie ||
 324                     bridge->pcie_type == PCI_EXP_TYPE_PCI_BRIDGE)
 325                         return 0;
 326
 327                 if (bridge->pcie_type == PCI_EXP_TYPE_ROOT_PORT) {
 328                         for (i = 0; i < atsru->devices_cnt; i++)
 329                                 if (atsru->devices[i] == bridge)
 330                                         return 1;
 331                         break;
 332                 }
 333         }
 334
 335         if (atsru->include_all)
 336                 return 1;
 337
 338         return 0;
 339 }
 340 #endif
 341
 342 static void __init
 343 dmar_table_print_dmar_entry(struct acpi_dmar_header *header)
 344 {
 345         struct acpi_dmar_hardware_unit *drhd;
 346         struct acpi_dmar_reserved_memory *rmrr;
 347         struct acpi_dmar_atsr *atsr;
 348         struct acpi_dmar_rhsa *rhsa;
 349
 350         switch (header->type) {
 351         case ACPI_DMAR_TYPE_HARDWARE_UNIT:
 352                 drhd = container_of(header, struct acpi_dmar_hardware_unit,
 353                                     header);
 354                 printk (KERN_INFO PREFIX
 355                         "DRHD base: %#016Lx flags: %#x\n",
 356                         (unsigned long long)drhd->address, drhd->flags);
 357                 break;
 358         case ACPI_DMAR_TYPE_RESERVED_MEMORY:
 359                 rmrr = container_of(header, struct acpi_dmar_reserved_memory,
 360                                     header);
 361                 printk (KERN_INFO PREFIX
 362                         "RMRR base: %#016Lx end: %#016Lx\n",
 363                         (unsigned long long)rmrr->base_address,
 364                         (unsigned long long)rmrr->end_address);
 365                 break;
 366         case ACPI_DMAR_TYPE_ATSR:
 367                 atsr = container_of(header, struct acpi_dmar_atsr, header);
 368                 printk(KERN_INFO PREFIX "ATSR flags: %#x\n", atsr->flags);
 369                 break;
 370         case ACPI_DMAR_HARDWARE_AFFINITY:
 371                 rhsa = container_of(header, struct acpi_dmar_rhsa, header);
 372                 printk(KERN_INFO PREFIX "RHSA base: %#016Lx proximity domain: %#x\n",
 373                        (unsigned long long)rhsa->base_address,
 374                        rhsa->proximity_domain);
 375                 break;
 376         }
 377 }
 378
 379 /**
 380  * dmar_table_detect - checks to see if the platform supports DMAR devices
 381  */
 382 static int __init dmar_table_detect(void)
 383 {
 384         acpi_status status = AE_OK;
 385
 386         /* if we could find DMAR table, then there are DMAR devices */
 387         status = acpi_get_table_with_size(ACPI_SIG_DMAR, 0,
 388                                 (struct acpi_table_header **)&dmar_tbl,
 389                                 &dmar_tbl_size);
 390
 391         if (ACPI_SUCCESS(status) && !dmar_tbl) {
 392                 printk (KERN_WARNING PREFIX "Unable to map DMAR\n");
 393                 status = AE_NOT_FOUND;
 394         }
 395
 396         return (ACPI_SUCCESS(status) ? 1 : 0);
 397 }
 398
 399 /**
 400  * parse_dmar_table - parses the DMA reporting table
 401  */
 402 static int __init
 403 parse_dmar_table(void)
 404 {
 405         struct acpi_table_dmar *dmar;
 406         struct acpi_dmar_header *entry_header;
 407         int ret = 0;
 408
 409         /*
 410          * Do it again, earlier dmar_tbl mapping could be mapped with
 411          * fixed map.
 412          */
 413         dmar_table_detect();
 414
 415         /*
 416          * ACPI tables may not be DMA protected by tboot, so use DMAR copy
 417          * SINIT saved in SinitMleData in TXT heap (which is DMA protected)
 418          */
 419         dmar_tbl = tboot_get_dmar_table(dmar_tbl);
 420
 421         dmar = (struct acpi_table_dmar *)dmar_tbl;
 422         if (!dmar)
 423                 return -ENODEV;
 424
 425         if (dmar->width < PAGE_SHIFT - 1) {
 426                 printk(KERN_WARNING PREFIX "Invalid DMAR haw\n");
 427                 return -EINVAL;
 428         }
 429
 430         printk (KERN_INFO PREFIX "Host address width %d\n",
 431                 dmar->width + 1);
 432
 433         entry_header = (struct acpi_dmar_header *)(dmar + 1);
 434         while (((unsigned long)entry_header) <
 435                         (((unsigned long)dmar) + dmar_tbl->length)) {
 436                 /* Avoid looping forever on bad ACPI tables */
 437                 if (entry_header->length == 0) {
 438                         printk(KERN_WARNING PREFIX
 439                                 "Invalid 0-length structure\n");
 440                         ret = -EINVAL;
 441                         break;
 442                 }
 443
 444                 dmar_table_print_dmar_entry(entry_header);
 445
 446                 switch (entry_header->type) {
 447                 case ACPI_DMAR_TYPE_HARDWARE_UNIT:
 448                         ret = dmar_parse_one_drhd(entry_header);
 449                         break;
 450                 case ACPI_DMAR_TYPE_RESERVED_MEMORY:
 451 #ifdef CONFIG_DMAR
 452                         ret = dmar_parse_one_rmrr(entry_header);
 453 #endif
 454                         break;
 455                 case ACPI_DMAR_TYPE_ATSR:
 456 #ifdef CONFIG_DMAR
 457                         ret = dmar_parse_one_atsr(entry_header);
 458 #endif
 459                         break;
 460                 case ACPI_DMAR_HARDWARE_AFFINITY:
 461                         /* We don't do anything with RHSA (yet?) */
 462                         break;
 463                 default:
 464                         printk(KERN_WARNING PREFIX
 465                                 "Unknown DMAR structure type %d\n",
 466                                 entry_header->type);
 467                         ret = 0; /* for forward compatibility */
 468                         break;
 469                 }
 470                 if (ret)
 471                         break;
 472
 473                 entry_header = ((void *)entry_header + entry_header->length);
 474         }
 475         return ret;
 476 }
 477
 478 int dmar_pci_device_match(struct pci_dev *devices[], int cnt,
 479                           struct pci_dev *dev)
 480 {
 481         int index;
 482
 483         while (dev) {
 484                 for (index = 0; index < cnt; index++)
 485                         if (dev == devices[index])
 486                                 return 1;
 487
 488                 /* Check our parent */
 489                 dev = dev->bus->self;
 490         }
 491
 492         return 0;
 493 }
 494
 495 struct dmar_drhd_unit *
 496 dmar_find_matched_drhd_unit(struct pci_dev *dev)
 497 {
 498         struct dmar_drhd_unit *dmaru = NULL;
 499         struct acpi_dmar_hardware_unit *drhd;
 500
 501         list_for_each_entry(dmaru, &dmar_drhd_units, list) {
 502                 drhd = container_of(dmaru->hdr,
 503                                     struct acpi_dmar_hardware_unit,
 504                                     header);
 505
 506                 if (dmaru->include_all &&
 507                     drhd->segment == pci_domain_nr(dev->bus))
 508                         return dmaru;
 509
 510                 if (dmar_pci_device_match(dmaru->devices,
 511                                           dmaru->devices_cnt, dev))
 512                         return dmaru;
 513         }
 514
 515         return NULL;
 516 }
 517
 518 int __init dmar_dev_scope_init(void)
 519 {
 520         struct dmar_drhd_unit *drhd, *drhd_n;
 521         int ret = -ENODEV;
 522
 523         list_for_each_entry_safe(drhd, drhd_n, &dmar_drhd_units, list) {
 524                 ret = dmar_parse_dev(drhd);
 525                 if (ret)
 526                         return ret;
 527         }
 528
 529 #ifdef CONFIG_DMAR
 530         {
 531                 struct dmar_rmrr_unit *rmrr, *rmrr_n;
 532                 struct dmar_atsr_unit *atsr, *atsr_n;
 533
 534                 list_for_each_entry_safe(rmrr, rmrr_n, &dmar_rmrr_units, list) {
 535                         ret = rmrr_parse_dev(rmrr);
 536                         if (ret)
 537                                 return ret;
 538                 }
 539
 540                 list_for_each_entry_safe(atsr, atsr_n, &dmar_atsr_units, list) {
 541                         ret = atsr_parse_dev(atsr);
 542                         if (ret)
 543                                 return ret;
 544                 }
 545         }
 546 #endif
 547
 548         return ret;
 549 }
 550
 551
 552 int __init dmar_table_init(void)
 553 {
 554         static int dmar_table_initialized;
 555         int ret;
 556
 557         if (dmar_table_initialized)
 558                 return 0;
 559
 560         dmar_table_initialized = 1;
 561
 562         ret = parse_dmar_table();
 563         if (ret) {
 564                 if (ret != -ENODEV)
 565                         printk(KERN_INFO PREFIX "parse DMAR table failure.\n");
 566                 return ret;
 567         }
 568
 569         if (list_empty(&dmar_drhd_units)) {
 570                 printk(KERN_INFO PREFIX "No DMAR devices found\n");
 571                 return -ENODEV;
 572         }
 573
 574 #ifdef CONFIG_DMAR
 575         if (list_empty(&dmar_rmrr_units))
 576                 printk(KERN_INFO PREFIX "No RMRR found\n");
 577
 578         if (list_empty(&dmar_atsr_units))
 579                 printk(KERN_INFO PREFIX "No ATSR found\n");
 580 #endif
 581
 582         return 0;
 583 }
 584
 585 int __init check_zero_address(void)
 586 {
 587         struct acpi_table_dmar *dmar;
 588         struct acpi_dmar_header *entry_header;
 589         struct acpi_dmar_hardware_unit *drhd;
 590
 591         dmar = (struct acpi_table_dmar *)dmar_tbl;
 592         entry_header = (struct acpi_dmar_header *)(dmar + 1);
 593
 594         while (((unsigned long)entry_header) <
 595                         (((unsigned long)dmar) + dmar_tbl->length)) {
 596                 /* Avoid looping forever on bad ACPI tables */
 597                 if (entry_header->length == 0) {
 598                         printk(KERN_WARNING PREFIX
 599                                 "Invalid 0-length structure\n");
 600                         return 0;
 601                 }
 602
 603                 if (entry_header->type == ACPI_DMAR_TYPE_HARDWARE_UNIT) {
 604                         drhd = (void *)entry_header;
 605                         if (!drhd->address) {
 606                                 /* Promote an attitude of violence to a BIOS engineer today */
 607                                 WARN(1, "Your BIOS is broken; DMAR reported at address zero!\n"
 608                                      "BIOS vendor: %s; Ver: %s; Product Version: %s\n",
 609                                      dmi_get_system_info(DMI_BIOS_VENDOR),
 610                                      dmi_get_system_info(DMI_BIOS_VERSION),
 611                                      dmi_get_system_info(DMI_PRODUCT_VERSION));
 612 #ifdef CONFIG_DMAR
 613                                 dmar_disabled = 1;
 614 #endif
 615                                 return 0;
 616                         }
 617                         break;
 618                 }
 619
 620                 entry_header = ((void *)entry_header + entry_header->length);
 621         }
 622         return 1;
 623 }
 624
 625 void __init detect_intel_iommu(void)
 626 {
 627         int ret;
 628
 629         ret = dmar_table_detect();
 630         if (ret)
 631                 ret = check_zero_address();
 632         {
 633 #ifdef CONFIG_INTR_REMAP
 634                 struct acpi_table_dmar *dmar;
 635                 /*
 636                  * for now we will disable dma-remapping when interrupt
 637                  * remapping is enabled.
 638                  * When support for queued invalidation for IOTLB invalidation
 639                  * is added, we will not need this any more.
 640                  */
 641                 dmar = (struct acpi_table_dmar *) dmar_tbl;
 642                 if (ret && cpu_has_x2apic && dmar->flags & 0x1)
 643                         printk(KERN_INFO
 644                                "Queued invalidation will be enabled to support "
 645                                "x2apic and Intr-remapping.\n");
 646 #endif
 647 #ifdef CONFIG_DMAR
 648                 if (ret && !no_iommu && !iommu_detected && !swiotlb &&
 649                     !dmar_disabled)
 650                         iommu_detected = 1;
 651 #endif
 652         }
 653         early_acpi_os_unmap_memory(dmar_tbl, dmar_tbl_size);
 654         dmar_tbl = NULL;
 655 }
 656
 657
 658 int alloc_iommu(struct dmar_drhd_unit *drhd)
 659 {
 660         struct intel_iommu *iommu;
 661         int map_size;
 662         u32 ver;
 663         static int iommu_allocated = 0;
 664         int agaw = 0;
 665         int msagaw = 0;
 666
 667         iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
 668         if (!iommu)
 669                 return -ENOMEM;
 670
 671         iommu->seq_id = iommu_allocated++;
 672         sprintf (iommu->name, "dmar%d", iommu->seq_id);
 673
 674         iommu->reg = ioremap(drhd->reg_base_addr, VTD_PAGE_SIZE);
 675         if (!iommu->reg) {
 676                 printk(KERN_ERR "IOMMU: can't map the region\n");
 677                 goto error;
 678         }
 679         iommu->cap = dmar_readq(iommu->reg + DMAR_CAP_REG);
 680         iommu->ecap = dmar_readq(iommu->reg + DMAR_ECAP_REG);
 681
 682         if (iommu->cap == (uint64_t)-1 && iommu->ecap == (uint64_t)-1) {
 683                 /* Promote an attitude of violence to a BIOS engineer today */
 684                 WARN(1, "Your BIOS is broken; DMAR reported at address %llx returns all ones!\n"
 685                      "BIOS vendor: %s; Ver: %s; Product Version: %s\n",
 686                      drhd->reg_base_addr,
 687                      dmi_get_system_info(DMI_BIOS_VENDOR),
 688                      dmi_get_system_info(DMI_BIOS_VERSION),
 689                      dmi_get_system_info(DMI_PRODUCT_VERSION));
 690                 goto err_unmap;
 691         }
 692
 693 #ifdef CONFIG_DMAR
 694         agaw = iommu_calculate_agaw(iommu);
 695         if (agaw < 0) {
 696                 printk(KERN_ERR
 697                        "Cannot get a valid agaw for iommu (seq_id = %d)\n",
 698                        iommu->seq_id);
 699                 goto err_unmap;
 700         }
 701         msagaw = iommu_calculate_max_sagaw(iommu);
 702         if (msagaw < 0) {
 703                 printk(KERN_ERR
 704                         "Cannot get a valid max agaw for iommu (seq_id = %d)\n",
 705                         iommu->seq_id);
 706                 goto err_unmap;
 707         }
 708 #endif
 709         iommu->agaw = agaw;
 710         iommu->msagaw = msagaw;
 711
 712         /* the registers might be more than one page */
 713         map_size = max_t(int, ecap_max_iotlb_offset(iommu->ecap),
 714                 cap_max_fault_reg_offset(iommu->cap));
 715         map_size = VTD_PAGE_ALIGN(map_size);
 716         if (map_size > VTD_PAGE_SIZE) {
 717                 iounmap(iommu->reg);
 718                 iommu->reg = ioremap(drhd->reg_base_addr, map_size);
 719                 if (!iommu->reg) {
 720                         printk(KERN_ERR "IOMMU: can't map the region\n");
 721                         goto error;
 722                 }
 723         }
 724
 725         ver = readl(iommu->reg + DMAR_VER_REG);
 726         pr_info("IOMMU %llx: ver %d:%d cap %llx ecap %llx\n",
 727                 (unsigned long long)drhd->reg_base_addr,
 728                 DMAR_VER_MAJOR(ver), DMAR_VER_MINOR(ver),
 729                 (unsigned long long)iommu->cap,
 730                 (unsigned long long)iommu->ecap);
 731
 732         spin_lock_init(&iommu->register_lock);
 733
 734         drhd->iommu = iommu;
 735         return 0;
 736
 737  err_unmap:
 738         iounmap(iommu->reg);
 739  error:
 740         kfree(iommu);
 741         return -1;
 742 }
 743
 744 void free_iommu(struct intel_iommu *iommu)
 745 {
 746         if (!iommu)
 747                 return;
 748
 749 #ifdef CONFIG_DMAR
 750         free_dmar_iommu(iommu);
 751 #endif
 752
 753         if (iommu->reg)
 754                 iounmap(iommu->reg);
 755         kfree(iommu);
 756 }
 757
 758 /*
 759  * Reclaim all the submitted descriptors which have completed its work.
 760  */
 761 static inline void reclaim_free_desc(struct q_inval *qi)
 762 {
 763         while (qi->desc_status[qi->free_tail] == QI_DONE ||
 764                qi->desc_status[qi->free_tail] == QI_ABORT) {
 765                 qi->desc_status[qi->free_tail] = QI_FREE;
 766                 qi->free_tail = (qi->free_tail + 1) % QI_LENGTH;
 767                 qi->free_cnt++;
 768         }
 769 }
 770
 771 static int qi_check_fault(struct intel_iommu *iommu, int index)
 772 {
 773         u32 fault;
 774         int head, tail;
 775         struct q_inval *qi = iommu->qi;
 776         int wait_index = (index + 1) % QI_LENGTH;
 777
 778         if (qi->desc_status[wait_index] == QI_ABORT)
 779                 return -EAGAIN;
 780
 781         fault = readl(iommu->reg + DMAR_FSTS_REG);
 782
 783         /*
 784          * If IQE happens, the head points to the descriptor associated
 785          * with the error. No new descriptors are fetched until the IQE
 786          * is cleared.
 787          */
 788         if (fault & DMA_FSTS_IQE) {
 789                 head = readl(iommu->reg + DMAR_IQH_REG);
 790                 if ((head >> DMAR_IQ_SHIFT) == index) {
 791                         printk(KERN_ERR "VT-d detected invalid descriptor: "
 792                                 "low=%llx, high=%llx\n",
 793                                 (unsigned long long)qi->desc[index].low,
 794                                 (unsigned long long)qi->desc[index].high);
 795                         memcpy(&qi->desc[index], &qi->desc[wait_index],
 796                                         sizeof(struct qi_desc));
 797                         __iommu_flush_cache(iommu, &qi->desc[index],
 798                                         sizeof(struct qi_desc));
 799                         writel(DMA_FSTS_IQE, iommu->reg + DMAR_FSTS_REG);
 800                         return -EINVAL;
 801                 }
 802         }
 803
 804         /*
 805          * If ITE happens, all pending wait_desc commands are aborted.
 806          * No new descriptors are fetched until the ITE is cleared.
 807          */
 808         if (fault & DMA_FSTS_ITE) {
 809                 head = readl(iommu->reg + DMAR_IQH_REG);
 810                 head = ((head >> DMAR_IQ_SHIFT) - 1 + QI_LENGTH) % QI_LENGTH;
 811                 head |= 1;
 812                 tail = readl(iommu->reg + DMAR_IQT_REG);
 813                 tail = ((tail >> DMAR_IQ_SHIFT) - 1 + QI_LENGTH) % QI_LENGTH;
 814
 815                 writel(DMA_FSTS_ITE, iommu->reg + DMAR_FSTS_REG);
 816
 817                 do {
 818                         if (qi->desc_status[head] == QI_IN_USE)
 819                                 qi->desc_status[head] = QI_ABORT;
 820                         head = (head - 2 + QI_LENGTH) % QI_LENGTH;
 821                 } while (head != tail);
 822
 823                 if (qi->desc_status[wait_index] == QI_ABORT)
 824                         return -EAGAIN;
 825         }
 826
 827         if (fault & DMA_FSTS_ICE)
 828                 writel(DMA_FSTS_ICE, iommu->reg + DMAR_FSTS_REG);
 829
 830         return 0;
 831 }
 832
 833 /*
 834  * Submit the queued invalidation descriptor to the remapping
 835  * hardware unit and wait for its completion.
 836  */
 837 int qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu)
 838 {
 839         int rc;
 840         struct q_inval *qi = iommu->qi;
 841         struct qi_desc *hw, wait_desc;
 842         int wait_index, index;
 843         unsigned long flags;
 844
 845         if (!qi)
 846                 return 0;
 847
 848         hw = qi->desc;
 849
 850 restart:
 851         rc = 0;
 852
 853         spin_lock_irqsave(&qi->q_lock, flags);
 854         while (qi->free_cnt < 3) {
 855                 spin_unlock_irqrestore(&qi->q_lock, flags);
 856                 cpu_relax();
 857                 spin_lock_irqsave(&qi->q_lock, flags);
 858         }
 859
 860         index = qi->free_head;
 861         wait_index = (index + 1) % QI_LENGTH;
 862
 863         qi->desc_status[index] = qi->desc_status[wait_index] = QI_IN_USE;
 864
 865         hw[index] = *desc;
 866
 867         wait_desc.low = QI_IWD_STATUS_DATA(QI_DONE) |
 868                         QI_IWD_STATUS_WRITE | QI_IWD_TYPE;
 869         wait_desc.high = virt_to_phys(&qi->desc_status[wait_index]);
 870
 871         hw[wait_index] = wait_desc;
 872
 873         __iommu_flush_cache(iommu, &hw[index], sizeof(struct qi_desc));
 874         __iommu_flush_cache(iommu, &hw[wait_index], sizeof(struct qi_desc));
 875
 876         qi->free_head = (qi->free_head + 2) % QI_LENGTH;
 877         qi->free_cnt -= 2;
 878
 879         /*
 880          * update the HW tail register indicating the presence of
 881          * new descriptors.
 882          */
 883         writel(qi->free_head << DMAR_IQ_SHIFT, iommu->reg + DMAR_IQT_REG);
 884
 885         while (qi->desc_status[wait_index] != QI_DONE) {
 886                 /*
 887                  * We will leave the interrupts disabled, to prevent interrupt
 888                  * context to queue another cmd while a cmd is already submitted
 889                  * and waiting for completion on this cpu. This is to avoid
 890                  * a deadlock where the interrupt context can wait indefinitely
 891                  * for free slots in the queue.
 892                  */
 893                 rc = qi_check_fault(iommu, index);
 894                 if (rc)
 895                         break;
 896
 897                 spin_unlock(&qi->q_lock);
 898                 cpu_relax();
 899                 spin_lock(&qi->q_lock);
 900         }
 901
 902         qi->desc_status[index] = QI_DONE;
 903
 904         reclaim_free_desc(qi);
 905         spin_unlock_irqrestore(&qi->q_lock, flags);
 906
 907         if (rc == -EAGAIN)
 908                 goto restart;
 909
 910         return rc;
 911 }
 912
 913 /*
 914  * Flush the global interrupt entry cache.
 915  */
 916 void qi_global_iec(struct intel_iommu *iommu)
 917 {
 918         struct qi_desc desc;
 919
 920         desc.low = QI_IEC_TYPE;
 921         desc.high = 0;
 922
 923         /* should never fail */
 924         qi_submit_sync(&desc, iommu);
 925 }
 926
 927 void qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, u8 fm,
 928                       u64 type)
 929 {
 930         struct qi_desc desc;
 931
 932         desc.low = QI_CC_FM(fm) | QI_CC_SID(sid) | QI_CC_DID(did)
 933                         | QI_CC_GRAN(type) | QI_CC_TYPE;
 934         desc.high = 0;
 935
 936         qi_submit_sync(&desc, iommu);
 937 }
 938
 939 void qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr,
 940                     unsigned int size_order, u64 type)
 941 {
 942         u8 dw = 0, dr = 0;
 943
 944         struct qi_desc desc;
 945         int ih = 0;
 946
 947         if (cap_write_drain(iommu->cap))
 948                 dw = 1;
 949
 950         if (cap_read_drain(iommu->cap))
 951                 dr = 1;
 952
 953         desc.low = QI_IOTLB_DID(did) | QI_IOTLB_DR(dr) | QI_IOTLB_DW(dw)
 954                 | QI_IOTLB_GRAN(type) | QI_IOTLB_TYPE;
 955         desc.high = QI_IOTLB_ADDR(addr) | QI_IOTLB_IH(ih)
 956                 | QI_IOTLB_AM(size_order);
 957
 958         qi_submit_sync(&desc, iommu);
 959 }
 960
 961 void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 qdep,
 962                         u64 addr, unsigned mask)
 963 {
 964         struct qi_desc desc;
 965
 966         if (mask) {
 967                 BUG_ON(addr & ((1 << (VTD_PAGE_SHIFT + mask)) - 1));
 968                 addr |= (1 << (VTD_PAGE_SHIFT + mask - 1)) - 1;
 969                 desc.high = QI_DEV_IOTLB_ADDR(addr) | QI_DEV_IOTLB_SIZE;
 970         } else
 971                 desc.high = QI_DEV_IOTLB_ADDR(addr);
 972
 973         if (qdep >= QI_DEV_IOTLB_MAX_INVS)
 974                 qdep = 0;
 975
 976         desc.low = QI_DEV_IOTLB_SID(sid) | QI_DEV_IOTLB_QDEP(qdep) |
 977                    QI_DIOTLB_TYPE;
 978
 979         qi_submit_sync(&desc, iommu);
 980 }
 981
 982 /*
 983  * Disable Queued Invalidation interface.
 984  */
 985 void dmar_disable_qi(struct intel_iommu *iommu)
 986 {
 987         unsigned long flags;
 988         u32 sts;
 989         cycles_t start_time = get_cycles();
 990
 991         if (!ecap_qis(iommu->ecap))
 992                 return;
 993
 994         spin_lock_irqsave(&iommu->register_lock, flags);
 995
 996         sts =  dmar_readq(iommu->reg + DMAR_GSTS_REG);
 997         if (!(sts & DMA_GSTS_QIES))
 998                 goto end;
 999
1000         /*
1001          * Give a chance to HW to complete the pending invalidation requests.
1002          */
1003         while ((readl(iommu->reg + DMAR_IQT_REG) !=
1004                 readl(iommu->reg + DMAR_IQH_REG)) &&
1005                 (DMAR_OPERATION_TIMEOUT > (get_cycles() - start_time)))
1006                 cpu_relax();
1007
1008         iommu->gcmd &= ~DMA_GCMD_QIE;
1009         writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
1010
1011         IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, readl,
1012                       !(sts & DMA_GSTS_QIES), sts);
1013 end:
1014         spin_unlock_irqrestore(&iommu->register_lock, flags);
1015 }
1016
1017 /*
1018  * Enable queued invalidation.
1019  */
1020 static void __dmar_enable_qi(struct intel_iommu *iommu)
1021 {
1022         u32 sts;
1023         unsigned long flags;
1024         struct q_inval *qi = iommu->qi;
1025
1026         qi->free_head = qi->free_tail = 0;
1027         qi->free_cnt = QI_LENGTH;
1028
1029         spin_lock_irqsave(&iommu->register_lock, flags);
1030
1031         /* write zero to the tail reg */
1032         writel(0, iommu->reg + DMAR_IQT_REG);
1033
1034         dmar_writeq(iommu->reg + DMAR_IQA_REG, virt_to_phys(qi->desc));
1035
1036         iommu->gcmd |= DMA_GCMD_QIE;
1037         writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
1038
1039         /* Make sure hardware complete it */
1040         IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, readl, (sts & DMA_GSTS_QIES), sts);
1041
1042         spin_unlock_irqrestore(&iommu->register_lock, flags);
1043 }
1044
1045 /*
1046  * Enable Queued Invalidation interface. This is a must to support
1047  * interrupt-remapping. Also used by DMA-remapping, which replaces
1048  * register based IOTLB invalidation.
1049  */
1050 int dmar_enable_qi(struct intel_iommu *iommu)
1051 {
1052         struct q_inval *qi;
1053
1054         if (!ecap_qis(iommu->ecap))
1055                 return -ENOENT;
1056
1057         /*
1058          * queued invalidation is already setup and enabled.
1059          */
1060         if (iommu->qi)
1061                 return 0;
1062
1063         iommu->qi = kmalloc(sizeof(*qi), GFP_ATOMIC);
1064         if (!iommu->qi)
1065                 return -ENOMEM;
1066
1067         qi = iommu->qi;
1068
1069         qi->desc = (void *)(get_zeroed_page(GFP_ATOMIC));
1070         if (!qi->desc) {
1071                 kfree(qi);
1072                 iommu->qi = 0;
1073                 return -ENOMEM;
1074         }
1075
1076         qi->desc_status = kmalloc(QI_LENGTH * sizeof(int), GFP_ATOMIC);
1077         if (!qi->desc_status) {
1078                 free_page((unsigned long) qi->desc);
1079                 kfree(qi);
1080                 iommu->qi = 0;
1081                 return -ENOMEM;
1082         }
1083
1084         qi->free_head = qi->free_tail = 0;
1085         qi->free_cnt = QI_LENGTH;
1086
1087         spin_lock_init(&qi->q_lock);
1088
1089         __dmar_enable_qi(iommu);
1090
1091         return 0;
1092 }
1093
1094 /* iommu interrupt handling. Most stuff are MSI-like. */
1095
1096 enum faulttype {
1097         DMA_REMAP,
1098         INTR_REMAP,
1099         UNKNOWN,
1100 };
1101
1102 static const char *dma_remap_fault_reasons[] =
1103 {
1104         "Software",
1105         "Present bit in root entry is clear",
1106         "Present bit in context entry is clear",
1107         "Invalid context entry",
1108         "Access beyond MGAW",
1109         "PTE Write access is not set",
1110         "PTE Read access is not set",
1111         "Next page table ptr is invalid",
1112         "Root table address invalid",
1113         "Context table ptr is invalid",
1114         "non-zero reserved fields in RTP",
1115         "non-zero reserved fields in CTP",
1116         "non-zero reserved fields in PTE",
1117 };
1118
1119 static const char *intr_remap_fault_reasons[] =
1120 {
1121         "Detected reserved fields in the decoded interrupt-remapped request",
1122         "Interrupt index exceeded the interrupt-remapping table size",
1123         "Present field in the IRTE entry is clear",
1124         "Error accessing interrupt-remapping table pointed by IRTA_REG",
1125         "Detected reserved fields in the IRTE entry",
1126         "Blocked a compatibility format interrupt request",
1127         "Blocked an interrupt request due to source-id verification failure",
1128 };
1129
1130 #define MAX_FAULT_REASON_IDX    (ARRAY_SIZE(fault_reason_strings) - 1)
1131
1132 const char *dmar_get_fault_reason(u8 fault_reason, int *fault_type)
1133 {
1134         if (fault_reason >= 0x20 && (fault_reason <= 0x20 +
1135                                      ARRAY_SIZE(intr_remap_fault_reasons))) {
1136                 *fault_type = INTR_REMAP;
1137                 return intr_remap_fault_reasons[fault_reason - 0x20];
1138         } else if (fault_reason < ARRAY_SIZE(dma_remap_fault_reasons)) {
1139                 *fault_type = DMA_REMAP;
1140                 return dma_remap_fault_reasons[fault_reason];
1141         } else {
1142                 *fault_type = UNKNOWN;
1143                 return "Unknown";
1144         }
1145 }
1146
1147 void dmar_msi_unmask(unsigned int irq)
1148 {
1149         struct intel_iommu *iommu = get_irq_data(irq);
1150         unsigned long flag;
1151
1152         /* unmask it */
1153         spin_lock_irqsave(&iommu->register_lock, flag);
1154         writel(0, iommu->reg + DMAR_FECTL_REG);
1155         /* Read a reg to force flush the post write */
1156         readl(iommu->reg + DMAR_FECTL_REG);
1157         spin_unlock_irqrestore(&iommu->register_lock, flag);
1158 }
1159
1160 void dmar_msi_mask(unsigned int irq)
1161 {
1162         unsigned long flag;
1163         struct intel_iommu *iommu = get_irq_data(irq);
1164
1165         /* mask it */
1166         spin_lock_irqsave(&iommu->register_lock, flag);
1167         writel(DMA_FECTL_IM, iommu->reg + DMAR_FECTL_REG);
1168         /* Read a reg to force flush the post write */
1169         readl(iommu->reg + DMAR_FECTL_REG);
1170         spin_unlock_irqrestore(&iommu->register_lock, flag);
1171 }
1172
1173 void dmar_msi_write(int irq, struct msi_msg *msg)
1174 {
1175         struct intel_iommu *iommu = get_irq_data(irq);
1176         unsigned long flag;
1177
1178         spin_lock_irqsave(&iommu->register_lock, flag);
1179         writel(msg->data, iommu->reg + DMAR_FEDATA_REG);
1180         writel(msg->address_lo, iommu->reg + DMAR_FEADDR_REG);
1181         writel(msg->address_hi, iommu->reg + DMAR_FEUADDR_REG);
1182         spin_unlock_irqrestore(&iommu->register_lock, flag);
1183 }
1184
1185 void dmar_msi_read(int irq, struct msi_msg *msg)
1186 {
1187         struct intel_iommu *iommu = get_irq_data(irq);
1188         unsigned long flag;
1189
1190         spin_lock_irqsave(&iommu->register_lock, flag);
1191         msg->data = readl(iommu->reg + DMAR_FEDATA_REG);
1192         msg->address_lo = readl(iommu->reg + DMAR_FEADDR_REG);
1193         msg->address_hi = readl(iommu->reg + DMAR_FEUADDR_REG);
1194         spin_unlock_irqrestore(&iommu->register_lock, flag);
1195 }
1196
1197 static int dmar_fault_do_one(struct intel_iommu *iommu, int type,
1198                 u8 fault_reason, u16 source_id, unsigned long long addr)
1199 {
1200         const char *reason;
1201         int fault_type;
1202
1203         reason = dmar_get_fault_reason(fault_reason, &fault_type);
1204
1205         if (fault_type == INTR_REMAP)
1206                 printk(KERN_ERR "INTR-REMAP: Request device [[%02x:%02x.%d] "
1207                        "fault index %llx\n"
1208                         "INTR-REMAP:[fault reason %02d] %s\n",
1209                         (source_id >> 8), PCI_SLOT(source_id & 0xFF),
1210                         PCI_FUNC(source_id & 0xFF), addr >> 48,
1211                         fault_reason, reason);
1212         else
1213                 printk(KERN_ERR
1214                        "DMAR:[%s] Request device [%02x:%02x.%d] "
1215                        "fault addr %llx \n"
1216                        "DMAR:[fault reason %02d] %s\n",
1217                        (type ? "DMA Read" : "DMA Write"),
1218                        (source_id >> 8), PCI_SLOT(source_id & 0xFF),
1219                        PCI_FUNC(source_id & 0xFF), addr, fault_reason, reason);
1220         return 0;
1221 }
1222
1223 #define PRIMARY_FAULT_REG_LEN (16)
1224 irqreturn_t dmar_fault(int irq, void *dev_id)
1225 {
1226         struct intel_iommu *iommu = dev_id;
1227         int reg, fault_index;
1228         u32 fault_status;
1229         unsigned long flag;
1230
1231         spin_lock_irqsave(&iommu->register_lock, flag);
1232         fault_status = readl(iommu->reg + DMAR_FSTS_REG);
1233         if (fault_status)
1234                 printk(KERN_ERR "DRHD: handling fault status reg %x\n",
1235                        fault_status);
1236
1237         /* TBD: ignore advanced fault log currently */
1238         if (!(fault_status & DMA_FSTS_PPF))
1239                 goto clear_rest;
1240
1241         fault_index = dma_fsts_fault_record_index(fault_status);
1242         reg = cap_fault_reg_offset(iommu->cap);
1243         while (1) {
1244                 u8 fault_reason;
1245                 u16 source_id;
1246                 u64 guest_addr;
1247                 int type;
1248                 u32 data;
1249
1250                 /* highest 32 bits */
1251                 data = readl(iommu->reg + reg +
1252                                 fault_index * PRIMARY_FAULT_REG_LEN + 12);
1253                 if (!(data & DMA_FRCD_F))
1254                         break;
1255
1256                 fault_reason = dma_frcd_fault_reason(data);
1257                 type = dma_frcd_type(data);
1258
1259                 data = readl(iommu->reg + reg +
1260                                 fault_index * PRIMARY_FAULT_REG_LEN + 8);
1261                 source_id = dma_frcd_source_id(data);
1262
1263                 guest_addr = dmar_readq(iommu->reg + reg +
1264                                 fault_index * PRIMARY_FAULT_REG_LEN);
1265                 guest_addr = dma_frcd_page_addr(guest_addr);
1266                 /* clear the fault */
1267                 writel(DMA_FRCD_F, iommu->reg + reg +
1268                         fault_index * PRIMARY_FAULT_REG_LEN + 12);
1269
1270                 spin_unlock_irqrestore(&iommu->register_lock, flag);
1271
1272                 dmar_fault_do_one(iommu, type, fault_reason,
1273                                 source_id, guest_addr);
1274
1275                 fault_index++;
1276                 if (fault_index >= cap_num_fault_regs(iommu->cap))
1277                         fault_index = 0;
1278                 spin_lock_irqsave(&iommu->register_lock, flag);
1279         }
1280 clear_rest:
1281         /* clear all the other faults */
1282         fault_status = readl(iommu->reg + DMAR_FSTS_REG);
1283         writel(fault_status, iommu->reg + DMAR_FSTS_REG);
1284
1285         spin_unlock_irqrestore(&iommu->register_lock, flag);
1286         return IRQ_HANDLED;
1287 }
1288
1289 int dmar_set_interrupt(struct intel_iommu *iommu)
1290 {
1291         int irq, ret;
1292
1293         /*
1294          * Check if the fault interrupt is already initialized.
1295          */
1296         if (iommu->irq)
1297                 return 0;
1298
1299         irq = create_irq();
1300         if (!irq) {
1301                 printk(KERN_ERR "IOMMU: no free vectors\n");
1302                 return -EINVAL;
1303         }
1304
1305         set_irq_data(irq, iommu);
1306         iommu->irq = irq;
1307
1308         ret = arch_setup_dmar_msi(irq);
1309         if (ret) {
1310                 set_irq_data(irq, NULL);
1311                 iommu->irq = 0;
1312                 destroy_irq(irq);
1313                 return ret;
1314         }
1315
1316         ret = request_irq(irq, dmar_fault, 0, iommu->name, iommu);
1317         if (ret)
1318                 printk(KERN_ERR "IOMMU: can't request irq\n");
1319         return ret;
1320 }
1321
1322 int __init enable_drhd_fault_handling(void)
1323 {
1324         struct dmar_drhd_unit *drhd;
1325
1326         /*
1327          * Enable fault control interrupt.
1328          */
1329         for_each_drhd_unit(drhd) {
1330                 int ret;
1331                 struct intel_iommu *iommu = drhd->iommu;
1332                 ret = dmar_set_interrupt(iommu);
1333
1334                 if (ret) {
1335                         printk(KERN_ERR "DRHD %Lx: failed to enable fault, "
1336                                " interrupt, ret %d\n",
1337                                (unsigned long long)drhd->reg_base_addr, ret);
1338                         return -1;
1339                 }
1340         }
1341
1342         return 0;
1343 }
1344
1345 /*
1346  * Re-enable Queued Invalidation interface.
1347  */
1348 int dmar_reenable_qi(struct intel_iommu *iommu)
1349 {
1350         if (!ecap_qis(iommu->ecap))
1351                 return -ENOENT;
1352
1353         if (!iommu->qi)
1354                 return -ENOENT;
1355
1356         /*
1357          * First disable queued invalidation.
1358          */
1359         dmar_disable_qi(iommu);
1360         /*
1361          * Then enable queued invalidation again. Since there is no pending
1362          * invalidation requests now, it's safe to re-enable queued
1363          * invalidation.
1364          */
1365         __dmar_enable_qi(iommu);
1366
1367         return 0;
1368 }
1369
1370 /*
1371  * Check interrupt remapping support in DMAR table description.
1372  */
1373 int dmar_ir_support(void)
1374 {
1375         struct acpi_table_dmar *dmar;
1376         dmar = (struct acpi_table_dmar *)dmar_tbl;
1377         return dmar->flags & 0x1;
1378 }