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
  35 #undef PREFIX
  36 #define PREFIX "DMAR:"
  37
  38 /* No locks are needed as DMA remapping hardware unit
  39  * list is constructed at boot time and hotplug of
  40  * these units are not supported by the architecture.
  41  */
  42 LIST_HEAD(dmar_drhd_units);
  43
  44 static struct acpi_table_header * __initdata dmar_tbl;
  45
  46 static void __init dmar_register_drhd_unit(struct dmar_drhd_unit *drhd)
  47 {
  48         /*
  49          * add INCLUDE_ALL at the tail, so scan the list will find it at
  50          * the very end.
  51          */
  52         if (drhd->include_all)
  53                 list_add_tail(&drhd->list, &dmar_drhd_units);
  54         else
  55                 list_add(&drhd->list, &dmar_drhd_units);
  56 }
  57
  58 static int __init dmar_parse_one_dev_scope(struct acpi_dmar_device_scope *scope,
  59                                            struct pci_dev **dev, u16 segment)
  60 {
  61         struct pci_bus *bus;
  62         struct pci_dev *pdev = NULL;
  63         struct acpi_dmar_pci_path *path;
  64         int count;
  65
  66         bus = pci_find_bus(segment, scope->bus);
  67         path = (struct acpi_dmar_pci_path *)(scope + 1);
  68         count = (scope->length - sizeof(struct acpi_dmar_device_scope))
  69                 / sizeof(struct acpi_dmar_pci_path);
  70
  71         while (count) {
  72                 if (pdev)
  73                         pci_dev_put(pdev);
  74                 /*
  75                  * Some BIOSes list non-exist devices in DMAR table, just
  76                  * ignore it
  77                  */
  78                 if (!bus) {
  79                         printk(KERN_WARNING
  80                         PREFIX "Device scope bus [%d] not found\n",
  81                         scope->bus);
  82                         break;
  83                 }
  84                 pdev = pci_get_slot(bus, PCI_DEVFN(path->dev, path->fn));
  85                 if (!pdev) {
  86                         printk(KERN_WARNING PREFIX
  87                         "Device scope device [%04x:%02x:%02x.%02x] not found\n",
  88                                 segment, bus->number, path->dev, path->fn);
  89                         break;
  90                 }
  91                 path ++;
  92                 count --;
  93                 bus = pdev->subordinate;
  94         }
  95         if (!pdev) {
  96                 printk(KERN_WARNING PREFIX
  97                 "Device scope device [%04x:%02x:%02x.%02x] not found\n",
  98                 segment, scope->bus, path->dev, path->fn);
  99                 *dev = NULL;
 100                 return 0;
 101         }
 102         if ((scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT && \
 103                         pdev->subordinate) || (scope->entry_type == \
 104                         ACPI_DMAR_SCOPE_TYPE_BRIDGE && !pdev->subordinate)) {
 105                 pci_dev_put(pdev);
 106                 printk(KERN_WARNING PREFIX
 107                         "Device scope type does not match for %s\n",
 108                          pci_name(pdev));
 109                 return -EINVAL;
 110         }
 111         *dev = pdev;
 112         return 0;
 113 }
 114
 115 static int __init dmar_parse_dev_scope(void *start, void *end, int *cnt,
 116                                        struct pci_dev ***devices, u16 segment)
 117 {
 118         struct acpi_dmar_device_scope *scope;
 119         void * tmp = start;
 120         int index;
 121         int ret;
 122
 123         *cnt = 0;
 124         while (start < end) {
 125                 scope = start;
 126                 if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT ||
 127                     scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE)
 128                         (*cnt)++;
 129                 else
 130                         printk(KERN_WARNING PREFIX
 131                                 "Unsupported device scope\n");
 132                 start += scope->length;
 133         }
 134         if (*cnt == 0)
 135                 return 0;
 136
 137         *devices = kcalloc(*cnt, sizeof(struct pci_dev *), GFP_KERNEL);
 138         if (!*devices)
 139                 return -ENOMEM;
 140
 141         start = tmp;
 142         index = 0;
 143         while (start < end) {
 144                 scope = start;
 145                 if (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT ||
 146                     scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE) {
 147                         ret = dmar_parse_one_dev_scope(scope,
 148                                 &(*devices)[index], segment);
 149                         if (ret) {
 150                                 kfree(*devices);
 151                                 return ret;
 152                         }
 153                         index ++;
 154                 }
 155                 start += scope->length;
 156         }
 157
 158         return 0;
 159 }
 160
 161 /**
 162  * dmar_parse_one_drhd - parses exactly one DMA remapping hardware definition
 163  * structure which uniquely represent one DMA remapping hardware unit
 164  * present in the platform
 165  */
 166 static int __init
 167 dmar_parse_one_drhd(struct acpi_dmar_header *header)
 168 {
 169         struct acpi_dmar_hardware_unit *drhd;
 170         struct dmar_drhd_unit *dmaru;
 171         int ret = 0;
 172
 173         dmaru = kzalloc(sizeof(*dmaru), GFP_KERNEL);
 174         if (!dmaru)
 175                 return -ENOMEM;
 176
 177         dmaru->hdr = header;
 178         drhd = (struct acpi_dmar_hardware_unit *)header;
 179         dmaru->reg_base_addr = drhd->address;
 180         dmaru->include_all = drhd->flags & 0x1; /* BIT0: INCLUDE_ALL */
 181
 182         ret = alloc_iommu(dmaru);
 183         if (ret) {
 184                 kfree(dmaru);
 185                 return ret;
 186         }
 187         dmar_register_drhd_unit(dmaru);
 188         return 0;
 189 }
 190
 191 static int __init dmar_parse_dev(struct dmar_drhd_unit *dmaru)
 192 {
 193         struct acpi_dmar_hardware_unit *drhd;
 194         int ret = 0;
 195
 196         drhd = (struct acpi_dmar_hardware_unit *) dmaru->hdr;
 197
 198         if (dmaru->include_all)
 199                 return 0;
 200
 201         ret = dmar_parse_dev_scope((void *)(drhd + 1),
 202                                 ((void *)drhd) + drhd->header.length,
 203                                 &dmaru->devices_cnt, &dmaru->devices,
 204                                 drhd->segment);
 205         if (ret) {
 206                 list_del(&dmaru->list);
 207                 kfree(dmaru);
 208         }
 209         return ret;
 210 }
 211
 212 #ifdef CONFIG_DMAR
 213 LIST_HEAD(dmar_rmrr_units);
 214
 215 static void __init dmar_register_rmrr_unit(struct dmar_rmrr_unit *rmrr)
 216 {
 217         list_add(&rmrr->list, &dmar_rmrr_units);
 218 }
 219
 220
 221 static int __init
 222 dmar_parse_one_rmrr(struct acpi_dmar_header *header)
 223 {
 224         struct acpi_dmar_reserved_memory *rmrr;
 225         struct dmar_rmrr_unit *rmrru;
 226
 227         rmrru = kzalloc(sizeof(*rmrru), GFP_KERNEL);
 228         if (!rmrru)
 229                 return -ENOMEM;
 230
 231         rmrru->hdr = header;
 232         rmrr = (struct acpi_dmar_reserved_memory *)header;
 233         rmrru->base_address = rmrr->base_address;
 234         rmrru->end_address = rmrr->end_address;
 235
 236         dmar_register_rmrr_unit(rmrru);
 237         return 0;
 238 }
 239
 240 static int __init
 241 rmrr_parse_dev(struct dmar_rmrr_unit *rmrru)
 242 {
 243         struct acpi_dmar_reserved_memory *rmrr;
 244         int ret;
 245
 246         rmrr = (struct acpi_dmar_reserved_memory *) rmrru->hdr;
 247         ret = dmar_parse_dev_scope((void *)(rmrr + 1),
 248                 ((void *)rmrr) + rmrr->header.length,
 249                 &rmrru->devices_cnt, &rmrru->devices, rmrr->segment);
 250
 251         if (ret || (rmrru->devices_cnt == 0)) {
 252                 list_del(&rmrru->list);
 253                 kfree(rmrru);
 254         }
 255         return ret;
 256 }
 257 #endif
 258
 259 static void __init
 260 dmar_table_print_dmar_entry(struct acpi_dmar_header *header)
 261 {
 262         struct acpi_dmar_hardware_unit *drhd;
 263         struct acpi_dmar_reserved_memory *rmrr;
 264
 265         switch (header->type) {
 266         case ACPI_DMAR_TYPE_HARDWARE_UNIT:
 267                 drhd = (struct acpi_dmar_hardware_unit *)header;
 268                 printk (KERN_INFO PREFIX
 269                         "DRHD (flags: 0x%08x)base: 0x%016Lx\n",
 270                         drhd->flags, (unsigned long long)drhd->address);
 271                 break;
 272         case ACPI_DMAR_TYPE_RESERVED_MEMORY:
 273                 rmrr = (struct acpi_dmar_reserved_memory *)header;
 274
 275                 printk (KERN_INFO PREFIX
 276                         "RMRR base: 0x%016Lx end: 0x%016Lx\n",
 277                         (unsigned long long)rmrr->base_address,
 278                         (unsigned long long)rmrr->end_address);
 279                 break;
 280         }
 281 }
 282
 283 /**
 284  * dmar_table_detect - checks to see if the platform supports DMAR devices
 285  */
 286 static int __init dmar_table_detect(void)
 287 {
 288         acpi_status status = AE_OK;
 289
 290         /* if we could find DMAR table, then there are DMAR devices */
 291         status = acpi_get_table(ACPI_SIG_DMAR, 0,
 292                                 (struct acpi_table_header **)&dmar_tbl);
 293
 294         if (ACPI_SUCCESS(status) && !dmar_tbl) {
 295                 printk (KERN_WARNING PREFIX "Unable to map DMAR\n");
 296                 status = AE_NOT_FOUND;
 297         }
 298
 299         return (ACPI_SUCCESS(status) ? 1 : 0);
 300 }
 301
 302 /**
 303  * parse_dmar_table - parses the DMA reporting table
 304  */
 305 static int __init
 306 parse_dmar_table(void)
 307 {
 308         struct acpi_table_dmar *dmar;
 309         struct acpi_dmar_header *entry_header;
 310         int ret = 0;
 311
 312         /*
 313          * Do it again, earlier dmar_tbl mapping could be mapped with
 314          * fixed map.
 315          */
 316         dmar_table_detect();
 317
 318         dmar = (struct acpi_table_dmar *)dmar_tbl;
 319         if (!dmar)
 320                 return -ENODEV;
 321
 322         if (dmar->width < PAGE_SHIFT - 1) {
 323                 printk(KERN_WARNING PREFIX "Invalid DMAR haw\n");
 324                 return -EINVAL;
 325         }
 326
 327         printk (KERN_INFO PREFIX "Host address width %d\n",
 328                 dmar->width + 1);
 329
 330         entry_header = (struct acpi_dmar_header *)(dmar + 1);
 331         while (((unsigned long)entry_header) <
 332                         (((unsigned long)dmar) + dmar_tbl->length)) {
 333                 dmar_table_print_dmar_entry(entry_header);
 334
 335                 switch (entry_header->type) {
 336                 case ACPI_DMAR_TYPE_HARDWARE_UNIT:
 337                         ret = dmar_parse_one_drhd(entry_header);
 338                         break;
 339                 case ACPI_DMAR_TYPE_RESERVED_MEMORY:
 340 #ifdef CONFIG_DMAR
 341                         ret = dmar_parse_one_rmrr(entry_header);
 342 #endif
 343                         break;
 344                 default:
 345                         printk(KERN_WARNING PREFIX
 346                                 "Unknown DMAR structure type\n");
 347                         ret = 0; /* for forward compatibility */
 348                         break;
 349                 }
 350                 if (ret)
 351                         break;
 352
 353                 entry_header = ((void *)entry_header + entry_header->length);
 354         }
 355         return ret;
 356 }
 357
 358 int dmar_pci_device_match(struct pci_dev *devices[], int cnt,
 359                           struct pci_dev *dev)
 360 {
 361         int index;
 362
 363         while (dev) {
 364                 for (index = 0; index < cnt; index++)
 365                         if (dev == devices[index])
 366                                 return 1;
 367
 368                 /* Check our parent */
 369                 dev = dev->bus->self;
 370         }
 371
 372         return 0;
 373 }
 374
 375 struct dmar_drhd_unit *
 376 dmar_find_matched_drhd_unit(struct pci_dev *dev)
 377 {
 378         struct dmar_drhd_unit *dmaru = NULL;
 379         struct acpi_dmar_hardware_unit *drhd;
 380
 381         list_for_each_entry(dmaru, &dmar_drhd_units, list) {
 382                 drhd = container_of(dmaru->hdr,
 383                                     struct acpi_dmar_hardware_unit,
 384                                     header);
 385
 386                 if (dmaru->include_all &&
 387                     drhd->segment == pci_domain_nr(dev->bus))
 388                         return dmaru;
 389
 390                 if (dmar_pci_device_match(dmaru->devices,
 391                                           dmaru->devices_cnt, dev))
 392                         return dmaru;
 393         }
 394
 395         return NULL;
 396 }
 397
 398 int __init dmar_dev_scope_init(void)
 399 {
 400         struct dmar_drhd_unit *drhd, *drhd_n;
 401         int ret = -ENODEV;
 402
 403         list_for_each_entry_safe(drhd, drhd_n, &dmar_drhd_units, list) {
 404                 ret = dmar_parse_dev(drhd);
 405                 if (ret)
 406                         return ret;
 407         }
 408
 409 #ifdef CONFIG_DMAR
 410         {
 411                 struct dmar_rmrr_unit *rmrr, *rmrr_n;
 412                 list_for_each_entry_safe(rmrr, rmrr_n, &dmar_rmrr_units, list) {
 413                         ret = rmrr_parse_dev(rmrr);
 414                         if (ret)
 415                                 return ret;
 416                 }
 417         }
 418 #endif
 419
 420         return ret;
 421 }
 422
 423
 424 int __init dmar_table_init(void)
 425 {
 426         static int dmar_table_initialized;
 427         int ret;
 428
 429         if (dmar_table_initialized)
 430                 return 0;
 431
 432         dmar_table_initialized = 1;
 433
 434         ret = parse_dmar_table();
 435         if (ret) {
 436                 if (ret != -ENODEV)
 437                         printk(KERN_INFO PREFIX "parse DMAR table failure.\n");
 438                 return ret;
 439         }
 440
 441         if (list_empty(&dmar_drhd_units)) {
 442                 printk(KERN_INFO PREFIX "No DMAR devices found\n");
 443                 return -ENODEV;
 444         }
 445
 446 #ifdef CONFIG_DMAR
 447         if (list_empty(&dmar_rmrr_units))
 448                 printk(KERN_INFO PREFIX "No RMRR found\n");
 449 #endif
 450
 451 #ifdef CONFIG_INTR_REMAP
 452         parse_ioapics_under_ir();
 453 #endif
 454         return 0;
 455 }
 456
 457 void __init detect_intel_iommu(void)
 458 {
 459         int ret;
 460
 461         ret = dmar_table_detect();
 462
 463         {
 464 #ifdef CONFIG_INTR_REMAP
 465                 struct acpi_table_dmar *dmar;
 466                 /*
 467                  * for now we will disable dma-remapping when interrupt
 468                  * remapping is enabled.
 469                  * When support for queued invalidation for IOTLB invalidation
 470                  * is added, we will not need this any more.
 471                  */
 472                 dmar = (struct acpi_table_dmar *) dmar_tbl;
 473                 if (ret && cpu_has_x2apic && dmar->flags & 0x1)
 474                         printk(KERN_INFO
 475                                "Queued invalidation will be enabled to support "
 476                                "x2apic and Intr-remapping.\n");
 477 #endif
 478 #ifdef CONFIG_DMAR
 479                 if (ret && !no_iommu && !iommu_detected && !swiotlb &&
 480                     !dmar_disabled)
 481                         iommu_detected = 1;
 482 #endif
 483         }
 484         dmar_tbl = NULL;
 485 }
 486
 487
 488 int alloc_iommu(struct dmar_drhd_unit *drhd)
 489 {
 490         struct intel_iommu *iommu;
 491         int map_size;
 492         u32 ver;
 493         static int iommu_allocated = 0;
 494         int agaw;
 495
 496         iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
 497         if (!iommu)
 498                 return -ENOMEM;
 499
 500         iommu->seq_id = iommu_allocated++;
 501
 502         iommu->reg = ioremap(drhd->reg_base_addr, VTD_PAGE_SIZE);
 503         if (!iommu->reg) {
 504                 printk(KERN_ERR "IOMMU: can't map the region\n");
 505                 goto error;
 506         }
 507         iommu->cap = dmar_readq(iommu->reg + DMAR_CAP_REG);
 508         iommu->ecap = dmar_readq(iommu->reg + DMAR_ECAP_REG);
 509
 510         agaw = iommu_calculate_agaw(iommu);
 511         if (agaw < 0) {
 512                 printk(KERN_ERR
 513                         "Cannot get a valid agaw for iommu (seq_id = %d)\n",
 514                         iommu->seq_id);
 515                 goto error;
 516         }
 517         iommu->agaw = agaw;
 518
 519         /* the registers might be more than one page */
 520         map_size = max_t(int, ecap_max_iotlb_offset(iommu->ecap),
 521                 cap_max_fault_reg_offset(iommu->cap));
 522         map_size = VTD_PAGE_ALIGN(map_size);
 523         if (map_size > VTD_PAGE_SIZE) {
 524                 iounmap(iommu->reg);
 525                 iommu->reg = ioremap(drhd->reg_base_addr, map_size);
 526                 if (!iommu->reg) {
 527                         printk(KERN_ERR "IOMMU: can't map the region\n");
 528                         goto error;
 529                 }
 530         }
 531
 532         ver = readl(iommu->reg + DMAR_VER_REG);
 533         pr_debug("IOMMU %llx: ver %d:%d cap %llx ecap %llx\n",
 534                 (unsigned long long)drhd->reg_base_addr,
 535                 DMAR_VER_MAJOR(ver), DMAR_VER_MINOR(ver),
 536                 (unsigned long long)iommu->cap,
 537                 (unsigned long long)iommu->ecap);
 538
 539         spin_lock_init(&iommu->register_lock);
 540
 541         drhd->iommu = iommu;
 542         return 0;
 543 error:
 544         kfree(iommu);
 545         return -1;
 546 }
 547
 548 void free_iommu(struct intel_iommu *iommu)
 549 {
 550         if (!iommu)
 551                 return;
 552
 553 #ifdef CONFIG_DMAR
 554         free_dmar_iommu(iommu);
 555 #endif
 556
 557         if (iommu->reg)
 558                 iounmap(iommu->reg);
 559         kfree(iommu);
 560 }
 561
 562 /*
 563  * Reclaim all the submitted descriptors which have completed its work.
 564  */
 565 static inline void reclaim_free_desc(struct q_inval *qi)
 566 {
 567         while (qi->desc_status[qi->free_tail] == QI_DONE) {
 568                 qi->desc_status[qi->free_tail] = QI_FREE;
 569                 qi->free_tail = (qi->free_tail + 1) % QI_LENGTH;
 570                 qi->free_cnt++;
 571         }
 572 }
 573
 574 /*
 575  * Submit the queued invalidation descriptor to the remapping
 576  * hardware unit and wait for its completion.
 577  */
 578 void qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu)
 579 {
 580         struct q_inval *qi = iommu->qi;
 581         struct qi_desc *hw, wait_desc;
 582         int wait_index, index;
 583         unsigned long flags;
 584
 585         if (!qi)
 586                 return;
 587
 588         hw = qi->desc;
 589
 590         spin_lock_irqsave(&qi->q_lock, flags);
 591         while (qi->free_cnt < 3) {
 592                 spin_unlock_irqrestore(&qi->q_lock, flags);
 593                 cpu_relax();
 594                 spin_lock_irqsave(&qi->q_lock, flags);
 595         }
 596
 597         index = qi->free_head;
 598         wait_index = (index + 1) % QI_LENGTH;
 599
 600         qi->desc_status[index] = qi->desc_status[wait_index] = QI_IN_USE;
 601
 602         hw[index] = *desc;
 603
 604         wait_desc.low = QI_IWD_STATUS_DATA(2) | QI_IWD_STATUS_WRITE | QI_IWD_TYPE;
 605         wait_desc.high = virt_to_phys(&qi->desc_status[wait_index]);
 606
 607         hw[wait_index] = wait_desc;
 608
 609         __iommu_flush_cache(iommu, &hw[index], sizeof(struct qi_desc));
 610         __iommu_flush_cache(iommu, &hw[wait_index], sizeof(struct qi_desc));
 611
 612         qi->free_head = (qi->free_head + 2) % QI_LENGTH;
 613         qi->free_cnt -= 2;
 614
 615         spin_lock(&iommu->register_lock);
 616         /*
 617          * update the HW tail register indicating the presence of
 618          * new descriptors.
 619          */
 620         writel(qi->free_head << 4, iommu->reg + DMAR_IQT_REG);
 621         spin_unlock(&iommu->register_lock);
 622
 623         while (qi->desc_status[wait_index] != QI_DONE) {
 624                 /*
 625                  * We will leave the interrupts disabled, to prevent interrupt
 626                  * context to queue another cmd while a cmd is already submitted
 627                  * and waiting for completion on this cpu. This is to avoid
 628                  * a deadlock where the interrupt context can wait indefinitely
 629                  * for free slots in the queue.
 630                  */
 631                 spin_unlock(&qi->q_lock);
 632                 cpu_relax();
 633                 spin_lock(&qi->q_lock);
 634         }
 635
 636         qi->desc_status[index] = QI_DONE;
 637
 638         reclaim_free_desc(qi);
 639         spin_unlock_irqrestore(&qi->q_lock, flags);
 640 }
 641
 642 /*
 643  * Flush the global interrupt entry cache.
 644  */
 645 void qi_global_iec(struct intel_iommu *iommu)
 646 {
 647         struct qi_desc desc;
 648
 649         desc.low = QI_IEC_TYPE;
 650         desc.high = 0;
 651
 652         qi_submit_sync(&desc, iommu);
 653 }
 654
 655 int qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, u8 fm,
 656                      u64 type, int non_present_entry_flush)
 657 {
 658
 659         struct qi_desc desc;
 660
 661         if (non_present_entry_flush) {
 662                 if (!cap_caching_mode(iommu->cap))
 663                         return 1;
 664                 else
 665                         did = 0;
 666         }
 667
 668         desc.low = QI_CC_FM(fm) | QI_CC_SID(sid) | QI_CC_DID(did)
 669                         | QI_CC_GRAN(type) | QI_CC_TYPE;
 670         desc.high = 0;
 671
 672         qi_submit_sync(&desc, iommu);
 673
 674         return 0;
 675
 676 }
 677
 678 int qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr,
 679                    unsigned int size_order, u64 type,
 680                    int non_present_entry_flush)
 681 {
 682         u8 dw = 0, dr = 0;
 683
 684         struct qi_desc desc;
 685         int ih = 0;
 686
 687         if (non_present_entry_flush) {
 688                 if (!cap_caching_mode(iommu->cap))
 689                         return 1;
 690                 else
 691                         did = 0;
 692         }
 693
 694         if (cap_write_drain(iommu->cap))
 695                 dw = 1;
 696
 697         if (cap_read_drain(iommu->cap))
 698                 dr = 1;
 699
 700         desc.low = QI_IOTLB_DID(did) | QI_IOTLB_DR(dr) | QI_IOTLB_DW(dw)
 701                 | QI_IOTLB_GRAN(type) | QI_IOTLB_TYPE;
 702         desc.high = QI_IOTLB_ADDR(addr) | QI_IOTLB_IH(ih)
 703                 | QI_IOTLB_AM(size_order);
 704
 705         qi_submit_sync(&desc, iommu);
 706
 707         return 0;
 708
 709 }
 710
 711 /*
 712  * Enable Queued Invalidation interface. This is a must to support
 713  * interrupt-remapping. Also used by DMA-remapping, which replaces
 714  * register based IOTLB invalidation.
 715  */
 716 int dmar_enable_qi(struct intel_iommu *iommu)
 717 {
 718         u32 cmd, sts;
 719         unsigned long flags;
 720         struct q_inval *qi;
 721
 722         if (!ecap_qis(iommu->ecap))
 723                 return -ENOENT;
 724
 725         /*
 726          * queued invalidation is already setup and enabled.
 727          */
 728         if (iommu->qi)
 729                 return 0;
 730
 731         iommu->qi = kmalloc(sizeof(*qi), GFP_KERNEL);
 732         if (!iommu->qi)
 733                 return -ENOMEM;
 734
 735         qi = iommu->qi;
 736
 737         qi->desc = (void *)(get_zeroed_page(GFP_KERNEL));
 738         if (!qi->desc) {
 739                 kfree(qi);
 740                 iommu->qi = 0;
 741                 return -ENOMEM;
 742         }
 743
 744         qi->desc_status = kmalloc(QI_LENGTH * sizeof(int), GFP_KERNEL);
 745         if (!qi->desc_status) {
 746                 free_page((unsigned long) qi->desc);
 747                 kfree(qi);
 748                 iommu->qi = 0;
 749                 return -ENOMEM;
 750         }
 751
 752         qi->free_head = qi->free_tail = 0;
 753         qi->free_cnt = QI_LENGTH;
 754
 755         spin_lock_init(&qi->q_lock);
 756
 757         spin_lock_irqsave(&iommu->register_lock, flags);
 758         /* write zero to the tail reg */
 759         writel(0, iommu->reg + DMAR_IQT_REG);
 760
 761         dmar_writeq(iommu->reg + DMAR_IQA_REG, virt_to_phys(qi->desc));
 762
 763         cmd = iommu->gcmd | DMA_GCMD_QIE;
 764         iommu->gcmd |= DMA_GCMD_QIE;
 765         writel(cmd, iommu->reg + DMAR_GCMD_REG);
 766
 767         /* Make sure hardware complete it */
 768         IOMMU_WAIT_OP(iommu, DMAR_GSTS_REG, readl, (sts & DMA_GSTS_QIES), sts);
 769         spin_unlock_irqrestore(&iommu->register_lock, flags);
 770
 771         return 0;
 772 }