1 /* 2 * Xen PCI - handle PCI (INTx) and MSI infrastructure calls for PV, HVM and 3 * initial domain support. We also handle the DSDT _PRT callbacks for GSI's 4 * used in HVM and initial domain mode (PV does not parse ACPI, so it has no 5 * concept of GSIs). Under PV we hook under the pnbbios API for IRQs and 6 * 0xcf8 PCI configuration read/write. 7 * 8 * Author: Ryan Wilson <hap9@epoch.ncsc.mil> 9 * Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> 10 * Stefano Stabellini <stefano.stabellini@eu.citrix.com> 11 */ 12 #include <linux/module.h> 13 #include <linux/init.h> 14 #include <linux/pci.h> 15 #include <linux/acpi.h> 16 17 #include <linux/io.h> 18 #include <asm/io_apic.h> 19 #include <asm/pci_x86.h> 20 21 #include <asm/xen/hypervisor.h> 22 23 #include <xen/features.h> 24 #include <xen/events.h> 25 #include <asm/xen/pci.h> 26 27 static int xen_pcifront_enable_irq(struct pci_dev *dev) 28 { 29 int rc; 30 int share = 1; 31 int pirq; 32 u8 gsi; 33 34 rc = pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &gsi); 35 if (rc < 0) { 36 dev_warn(&dev->dev, "Xen PCI: failed to read interrupt line: %d\n", 37 rc); 38 return rc; 39 } 40 /* In PV DomU the Xen PCI backend puts the PIRQ in the interrupt line.*/ 41 pirq = gsi; 42 43 if (gsi < NR_IRQS_LEGACY) 44 share = 0; 45 46 rc = xen_bind_pirq_gsi_to_irq(gsi, pirq, share, "pcifront"); 47 if (rc < 0) { 48 dev_warn(&dev->dev, "Xen PCI: failed to bind GSI%d (PIRQ%d) to IRQ: %d\n", 49 gsi, pirq, rc); 50 return rc; 51 } 52 53 dev->irq = rc; 54 dev_info(&dev->dev, "Xen PCI mapped GSI%d to IRQ%d\n", gsi, dev->irq); 55 return 0; 56 } 57 58 #ifdef CONFIG_ACPI 59 static int xen_register_pirq(u32 gsi, int gsi_override, int triggering, 60 bool set_pirq) 61 { 62 int rc, pirq = -1, irq = -1; 63 struct physdev_map_pirq map_irq; 64 int shareable = 0; 65 char *name; 66 67 irq = xen_irq_from_gsi(gsi); 68 if (irq > 0) 69 return irq; 70 71 if (set_pirq) 72 pirq = gsi; 73 74 map_irq.domid = DOMID_SELF; 75 map_irq.type = MAP_PIRQ_TYPE_GSI; 76 map_irq.index = gsi; 77 map_irq.pirq = pirq; 78 79 rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq); 80 if (rc) { 81 printk(KERN_WARNING "xen map irq failed %d\n", rc); 82 return -1; 83 } 84 85 if (triggering == ACPI_EDGE_SENSITIVE) { 86 shareable = 0; 87 name = "ioapic-edge"; 88 } else { 89 shareable = 1; 90 name = "ioapic-level"; 91 } 92 93 if (gsi_override >= 0) 94 gsi = gsi_override; 95 96 irq = xen_bind_pirq_gsi_to_irq(gsi, map_irq.pirq, shareable, name); 97 if (irq < 0) 98 goto out; 99 100 printk(KERN_DEBUG "xen: --> pirq=%d -> irq=%d (gsi=%d)\n", map_irq.pirq, irq, gsi); 101 out: 102 return irq; 103 } 104 105 static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi, 106 int trigger, int polarity) 107 { 108 if (!xen_hvm_domain()) 109 return -1; 110 111 return xen_register_pirq(gsi, -1 /* no GSI override */, trigger, 112 false /* no mapping of GSI to PIRQ */); 113 } 114 115 #ifdef CONFIG_XEN_DOM0 116 static int xen_register_gsi(u32 gsi, int gsi_override, int triggering, int polarity) 117 { 118 int rc, irq; 119 struct physdev_setup_gsi setup_gsi; 120 121 if (!xen_pv_domain()) 122 return -1; 123 124 printk(KERN_DEBUG "xen: registering gsi %u triggering %d polarity %d\n", 125 gsi, triggering, polarity); 126 127 irq = xen_register_pirq(gsi, gsi_override, triggering, true); 128 129 setup_gsi.gsi = gsi; 130 setup_gsi.triggering = (triggering == ACPI_EDGE_SENSITIVE ? 0 : 1); 131 setup_gsi.polarity = (polarity == ACPI_ACTIVE_HIGH ? 0 : 1); 132 133 rc = HYPERVISOR_physdev_op(PHYSDEVOP_setup_gsi, &setup_gsi); 134 if (rc == -EEXIST) 135 printk(KERN_INFO "Already setup the GSI :%d\n", gsi); 136 else if (rc) { 137 printk(KERN_ERR "Failed to setup GSI :%d, err_code:%d\n", 138 gsi, rc); 139 } 140 141 return irq; 142 } 143 144 static int acpi_register_gsi_xen(struct device *dev, u32 gsi, 145 int trigger, int polarity) 146 { 147 return xen_register_gsi(gsi, -1 /* no GSI override */, trigger, polarity); 148 } 149 #endif 150 #endif 151 152 #if defined(CONFIG_PCI_MSI) 153 #include <linux/msi.h> 154 #include <asm/msidef.h> 155 156 struct xen_pci_frontend_ops *xen_pci_frontend; 157 EXPORT_SYMBOL_GPL(xen_pci_frontend); 158 159 static int xen_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) 160 { 161 int irq, ret, i; 162 struct msi_desc *msidesc; 163 int *v; 164 165 if (type == PCI_CAP_ID_MSI && nvec > 1) 166 return 1; 167 168 v = kzalloc(sizeof(int) * max(1, nvec), GFP_KERNEL); 169 if (!v) 170 return -ENOMEM; 171 172 if (type == PCI_CAP_ID_MSIX) 173 ret = xen_pci_frontend_enable_msix(dev, v, nvec); 174 else 175 ret = xen_pci_frontend_enable_msi(dev, v); 176 if (ret) 177 goto error; 178 i = 0; 179 list_for_each_entry(msidesc, &dev->msi_list, list) { 180 irq = xen_bind_pirq_msi_to_irq(dev, msidesc, v[i], 181 (type == PCI_CAP_ID_MSI) ? nvec : 1, 182 (type == PCI_CAP_ID_MSIX) ? 183 "pcifront-msi-x" : 184 "pcifront-msi", 185 DOMID_SELF); 186 if (irq < 0) { 187 ret = irq; 188 goto free; 189 } 190 i++; 191 } 192 kfree(v); 193 return 0; 194 195 error: 196 dev_err(&dev->dev, "Xen PCI frontend has not registered MSI/MSI-X support!\n"); 197 free: 198 kfree(v); 199 return ret; 200 } 201 202 #define XEN_PIRQ_MSI_DATA (MSI_DATA_TRIGGER_EDGE | \ 203 MSI_DATA_LEVEL_ASSERT | (3 << 8) | MSI_DATA_VECTOR(0)) 204 205 static void xen_msi_compose_msg(struct pci_dev *pdev, unsigned int pirq, 206 struct msi_msg *msg) 207 { 208 /* We set vector == 0 to tell the hypervisor we don't care about it, 209 * but we want a pirq setup instead. 210 * We use the dest_id field to pass the pirq that we want. */ 211 msg->address_hi = MSI_ADDR_BASE_HI | MSI_ADDR_EXT_DEST_ID(pirq); 212 msg->address_lo = 213 MSI_ADDR_BASE_LO | 214 MSI_ADDR_DEST_MODE_PHYSICAL | 215 MSI_ADDR_REDIRECTION_CPU | 216 MSI_ADDR_DEST_ID(pirq); 217 218 msg->data = XEN_PIRQ_MSI_DATA; 219 } 220 221 static int xen_hvm_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) 222 { 223 int irq, pirq; 224 struct msi_desc *msidesc; 225 struct msi_msg msg; 226 227 if (type == PCI_CAP_ID_MSI && nvec > 1) 228 return 1; 229 230 list_for_each_entry(msidesc, &dev->msi_list, list) { 231 __read_msi_msg(msidesc, &msg); 232 pirq = MSI_ADDR_EXT_DEST_ID(msg.address_hi) | 233 ((msg.address_lo >> MSI_ADDR_DEST_ID_SHIFT) & 0xff); 234 if (msg.data != XEN_PIRQ_MSI_DATA || 235 xen_irq_from_pirq(pirq) < 0) { 236 pirq = xen_allocate_pirq_msi(dev, msidesc); 237 if (pirq < 0) { 238 irq = -ENODEV; 239 goto error; 240 } 241 xen_msi_compose_msg(dev, pirq, &msg); 242 __write_msi_msg(msidesc, &msg); 243 dev_dbg(&dev->dev, "xen: msi bound to pirq=%d\n", pirq); 244 } else { 245 dev_dbg(&dev->dev, 246 "xen: msi already bound to pirq=%d\n", pirq); 247 } 248 irq = xen_bind_pirq_msi_to_irq(dev, msidesc, pirq, 249 (type == PCI_CAP_ID_MSI) ? nvec : 1, 250 (type == PCI_CAP_ID_MSIX) ? 251 "msi-x" : "msi", 252 DOMID_SELF); 253 if (irq < 0) 254 goto error; 255 dev_dbg(&dev->dev, 256 "xen: msi --> pirq=%d --> irq=%d\n", pirq, irq); 257 } 258 return 0; 259 260 error: 261 dev_err(&dev->dev, 262 "Xen PCI frontend has not registered MSI/MSI-X support!\n"); 263 return irq; 264 } 265 266 #ifdef CONFIG_XEN_DOM0 267 static bool __read_mostly pci_seg_supported = true; 268 269 static int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) 270 { 271 int ret = 0; 272 struct msi_desc *msidesc; 273 274 list_for_each_entry(msidesc, &dev->msi_list, list) { 275 struct physdev_map_pirq map_irq; 276 domid_t domid; 277 278 domid = ret = xen_find_device_domain_owner(dev); 279 /* N.B. Casting int's -ENODEV to uint16_t results in 0xFFED, 280 * hence check ret value for < 0. */ 281 if (ret < 0) 282 domid = DOMID_SELF; 283 284 memset(&map_irq, 0, sizeof(map_irq)); 285 map_irq.domid = domid; 286 map_irq.type = MAP_PIRQ_TYPE_MSI_SEG; 287 map_irq.index = -1; 288 map_irq.pirq = -1; 289 map_irq.bus = dev->bus->number | 290 (pci_domain_nr(dev->bus) << 16); 291 map_irq.devfn = dev->devfn; 292 293 if (type == PCI_CAP_ID_MSI && nvec > 1) { 294 map_irq.type = MAP_PIRQ_TYPE_MULTI_MSI; 295 map_irq.entry_nr = nvec; 296 } else if (type == PCI_CAP_ID_MSIX) { 297 int pos; 298 u32 table_offset, bir; 299 300 pos = dev->msix_cap; 301 pci_read_config_dword(dev, pos + PCI_MSIX_TABLE, 302 &table_offset); 303 bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR); 304 305 map_irq.table_base = pci_resource_start(dev, bir); 306 map_irq.entry_nr = msidesc->msi_attrib.entry_nr; 307 } 308 309 ret = -EINVAL; 310 if (pci_seg_supported) 311 ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, 312 &map_irq); 313 if (type == PCI_CAP_ID_MSI && nvec > 1 && ret) { 314 /* 315 * If MAP_PIRQ_TYPE_MULTI_MSI is not available 316 * there's nothing else we can do in this case. 317 * Just set ret > 0 so driver can retry with 318 * single MSI. 319 */ 320 ret = 1; 321 goto out; 322 } 323 if (ret == -EINVAL && !pci_domain_nr(dev->bus)) { 324 map_irq.type = MAP_PIRQ_TYPE_MSI; 325 map_irq.index = -1; 326 map_irq.pirq = -1; 327 map_irq.bus = dev->bus->number; 328 ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, 329 &map_irq); 330 if (ret != -EINVAL) 331 pci_seg_supported = false; 332 } 333 if (ret) { 334 dev_warn(&dev->dev, "xen map irq failed %d for %d domain\n", 335 ret, domid); 336 goto out; 337 } 338 339 ret = xen_bind_pirq_msi_to_irq(dev, msidesc, map_irq.pirq, 340 (type == PCI_CAP_ID_MSI) ? nvec : 1, 341 (type == PCI_CAP_ID_MSIX) ? "msi-x" : "msi", 342 domid); 343 if (ret < 0) 344 goto out; 345 } 346 ret = 0; 347 out: 348 return ret; 349 } 350 351 static void xen_initdom_restore_msi_irqs(struct pci_dev *dev) 352 { 353 int ret = 0; 354 355 if (pci_seg_supported) { 356 struct physdev_pci_device restore_ext; 357 358 restore_ext.seg = pci_domain_nr(dev->bus); 359 restore_ext.bus = dev->bus->number; 360 restore_ext.devfn = dev->devfn; 361 ret = HYPERVISOR_physdev_op(PHYSDEVOP_restore_msi_ext, 362 &restore_ext); 363 if (ret == -ENOSYS) 364 pci_seg_supported = false; 365 WARN(ret && ret != -ENOSYS, "restore_msi_ext -> %d\n", ret); 366 } 367 if (!pci_seg_supported) { 368 struct physdev_restore_msi restore; 369 370 restore.bus = dev->bus->number; 371 restore.devfn = dev->devfn; 372 ret = HYPERVISOR_physdev_op(PHYSDEVOP_restore_msi, &restore); 373 WARN(ret && ret != -ENOSYS, "restore_msi -> %d\n", ret); 374 } 375 } 376 #endif 377 378 static void xen_teardown_msi_irqs(struct pci_dev *dev) 379 { 380 struct msi_desc *msidesc; 381 382 msidesc = list_entry(dev->msi_list.next, struct msi_desc, list); 383 if (msidesc->msi_attrib.is_msix) 384 xen_pci_frontend_disable_msix(dev); 385 else 386 xen_pci_frontend_disable_msi(dev); 387 388 /* Free the IRQ's and the msidesc using the generic code. */ 389 default_teardown_msi_irqs(dev); 390 } 391 392 static void xen_teardown_msi_irq(unsigned int irq) 393 { 394 xen_destroy_irq(irq); 395 } 396 static u32 xen_nop_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) 397 { 398 return 0; 399 } 400 static u32 xen_nop_msix_mask_irq(struct msi_desc *desc, u32 flag) 401 { 402 return 0; 403 } 404 #endif 405 406 int __init pci_xen_init(void) 407 { 408 if (!xen_pv_domain() || xen_initial_domain()) 409 return -ENODEV; 410 411 printk(KERN_INFO "PCI: setting up Xen PCI frontend stub\n"); 412 413 pcibios_set_cache_line_size(); 414 415 pcibios_enable_irq = xen_pcifront_enable_irq; 416 pcibios_disable_irq = NULL; 417 418 #ifdef CONFIG_ACPI 419 /* Keep ACPI out of the picture */ 420 acpi_noirq = 1; 421 #endif 422 423 #ifdef CONFIG_PCI_MSI 424 x86_msi.setup_msi_irqs = xen_setup_msi_irqs; 425 x86_msi.teardown_msi_irq = xen_teardown_msi_irq; 426 x86_msi.teardown_msi_irqs = xen_teardown_msi_irqs; 427 x86_msi.msi_mask_irq = xen_nop_msi_mask_irq; 428 x86_msi.msix_mask_irq = xen_nop_msix_mask_irq; 429 #endif 430 return 0; 431 } 432 433 int __init pci_xen_hvm_init(void) 434 { 435 if (!xen_have_vector_callback || !xen_feature(XENFEAT_hvm_pirqs)) 436 return 0; 437 438 #ifdef CONFIG_ACPI 439 /* 440 * We don't want to change the actual ACPI delivery model, 441 * just how GSIs get registered. 442 */ 443 __acpi_register_gsi = acpi_register_gsi_xen_hvm; 444 #endif 445 446 #ifdef CONFIG_PCI_MSI 447 x86_msi.setup_msi_irqs = xen_hvm_setup_msi_irqs; 448 x86_msi.teardown_msi_irq = xen_teardown_msi_irq; 449 #endif 450 return 0; 451 } 452 453 #ifdef CONFIG_XEN_DOM0 454 static __init void xen_setup_acpi_sci(void) 455 { 456 int rc; 457 int trigger, polarity; 458 int gsi = acpi_sci_override_gsi; 459 int irq = -1; 460 int gsi_override = -1; 461 462 if (!gsi) 463 return; 464 465 rc = acpi_get_override_irq(gsi, &trigger, &polarity); 466 if (rc) { 467 printk(KERN_WARNING "xen: acpi_get_override_irq failed for acpi" 468 " sci, rc=%d\n", rc); 469 return; 470 } 471 trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE; 472 polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH; 473 474 printk(KERN_INFO "xen: sci override: global_irq=%d trigger=%d " 475 "polarity=%d\n", gsi, trigger, polarity); 476 477 /* Before we bind the GSI to a Linux IRQ, check whether 478 * we need to override it with bus_irq (IRQ) value. Usually for 479 * IRQs below IRQ_LEGACY_IRQ this holds IRQ == GSI, as so: 480 * ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 low level) 481 * but there are oddballs where the IRQ != GSI: 482 * ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 20 low level) 483 * which ends up being: gsi_to_irq[9] == 20 484 * (which is what acpi_gsi_to_irq ends up calling when starting the 485 * the ACPI interpreter and keels over since IRQ 9 has not been 486 * setup as we had setup IRQ 20 for it). 487 */ 488 if (acpi_gsi_to_irq(gsi, &irq) == 0) { 489 /* Use the provided value if it's valid. */ 490 if (irq >= 0) 491 gsi_override = irq; 492 } 493 494 gsi = xen_register_gsi(gsi, gsi_override, trigger, polarity); 495 printk(KERN_INFO "xen: acpi sci %d\n", gsi); 496 497 return; 498 } 499 500 int __init pci_xen_initial_domain(void) 501 { 502 int irq; 503 504 #ifdef CONFIG_PCI_MSI 505 x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs; 506 x86_msi.teardown_msi_irq = xen_teardown_msi_irq; 507 x86_msi.restore_msi_irqs = xen_initdom_restore_msi_irqs; 508 x86_msi.msi_mask_irq = xen_nop_msi_mask_irq; 509 x86_msi.msix_mask_irq = xen_nop_msix_mask_irq; 510 #endif 511 xen_setup_acpi_sci(); 512 __acpi_register_gsi = acpi_register_gsi_xen; 513 /* Pre-allocate legacy irqs */ 514 for (irq = 0; irq < NR_IRQS_LEGACY; irq++) { 515 int trigger, polarity; 516 517 if (acpi_get_override_irq(irq, &trigger, &polarity) == -1) 518 continue; 519 520 xen_register_pirq(irq, -1 /* no GSI override */, 521 trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE, 522 true /* Map GSI to PIRQ */); 523 } 524 if (0 == nr_ioapics) { 525 for (irq = 0; irq < NR_IRQS_LEGACY; irq++) 526 xen_bind_pirq_gsi_to_irq(irq, irq, 0, "xt-pic"); 527 } 528 return 0; 529 } 530 531 struct xen_device_domain_owner { 532 domid_t domain; 533 struct pci_dev *dev; 534 struct list_head list; 535 }; 536 537 static DEFINE_SPINLOCK(dev_domain_list_spinlock); 538 static struct list_head dev_domain_list = LIST_HEAD_INIT(dev_domain_list); 539 540 static struct xen_device_domain_owner *find_device(struct pci_dev *dev) 541 { 542 struct xen_device_domain_owner *owner; 543 544 list_for_each_entry(owner, &dev_domain_list, list) { 545 if (owner->dev == dev) 546 return owner; 547 } 548 return NULL; 549 } 550 551 int xen_find_device_domain_owner(struct pci_dev *dev) 552 { 553 struct xen_device_domain_owner *owner; 554 int domain = -ENODEV; 555 556 spin_lock(&dev_domain_list_spinlock); 557 owner = find_device(dev); 558 if (owner) 559 domain = owner->domain; 560 spin_unlock(&dev_domain_list_spinlock); 561 return domain; 562 } 563 EXPORT_SYMBOL_GPL(xen_find_device_domain_owner); 564 565 int xen_register_device_domain_owner(struct pci_dev *dev, uint16_t domain) 566 { 567 struct xen_device_domain_owner *owner; 568 569 owner = kzalloc(sizeof(struct xen_device_domain_owner), GFP_KERNEL); 570 if (!owner) 571 return -ENODEV; 572 573 spin_lock(&dev_domain_list_spinlock); 574 if (find_device(dev)) { 575 spin_unlock(&dev_domain_list_spinlock); 576 kfree(owner); 577 return -EEXIST; 578 } 579 owner->domain = domain; 580 owner->dev = dev; 581 list_add_tail(&owner->list, &dev_domain_list); 582 spin_unlock(&dev_domain_list_spinlock); 583 return 0; 584 } 585 EXPORT_SYMBOL_GPL(xen_register_device_domain_owner); 586 587 int xen_unregister_device_domain_owner(struct pci_dev *dev) 588 { 589 struct xen_device_domain_owner *owner; 590 591 spin_lock(&dev_domain_list_spinlock); 592 owner = find_device(dev); 593 if (!owner) { 594 spin_unlock(&dev_domain_list_spinlock); 595 return -ENODEV; 596 } 597 list_del(&owner->list); 598 spin_unlock(&dev_domain_list_spinlock); 599 kfree(owner); 600 return 0; 601 } 602 EXPORT_SYMBOL_GPL(xen_unregister_device_domain_owner); 603 #endif 604