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 if (set_pirq) 68 pirq = gsi; 69 70 map_irq.domid = DOMID_SELF; 71 map_irq.type = MAP_PIRQ_TYPE_GSI; 72 map_irq.index = gsi; 73 map_irq.pirq = pirq; 74 75 rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq); 76 if (rc) { 77 printk(KERN_WARNING "xen map irq failed %d\n", rc); 78 return -1; 79 } 80 81 if (triggering == ACPI_EDGE_SENSITIVE) { 82 shareable = 0; 83 name = "ioapic-edge"; 84 } else { 85 shareable = 1; 86 name = "ioapic-level"; 87 } 88 89 if (gsi_override >= 0) 90 gsi = gsi_override; 91 92 irq = xen_bind_pirq_gsi_to_irq(gsi, map_irq.pirq, shareable, name); 93 if (irq < 0) 94 goto out; 95 96 printk(KERN_DEBUG "xen: --> pirq=%d -> irq=%d (gsi=%d)\n", map_irq.pirq, irq, gsi); 97 out: 98 return irq; 99 } 100 101 static int acpi_register_gsi_xen_hvm(struct device *dev, u32 gsi, 102 int trigger, int polarity) 103 { 104 if (!xen_hvm_domain()) 105 return -1; 106 107 return xen_register_pirq(gsi, -1 /* no GSI override */, trigger, 108 false /* no mapping of GSI to PIRQ */); 109 } 110 111 #ifdef CONFIG_XEN_DOM0 112 static int xen_register_gsi(u32 gsi, int gsi_override, int triggering, int polarity) 113 { 114 int rc, irq; 115 struct physdev_setup_gsi setup_gsi; 116 117 if (!xen_pv_domain()) 118 return -1; 119 120 printk(KERN_DEBUG "xen: registering gsi %u triggering %d polarity %d\n", 121 gsi, triggering, polarity); 122 123 irq = xen_register_pirq(gsi, gsi_override, triggering, true); 124 125 setup_gsi.gsi = gsi; 126 setup_gsi.triggering = (triggering == ACPI_EDGE_SENSITIVE ? 0 : 1); 127 setup_gsi.polarity = (polarity == ACPI_ACTIVE_HIGH ? 0 : 1); 128 129 rc = HYPERVISOR_physdev_op(PHYSDEVOP_setup_gsi, &setup_gsi); 130 if (rc == -EEXIST) 131 printk(KERN_INFO "Already setup the GSI :%d\n", gsi); 132 else if (rc) { 133 printk(KERN_ERR "Failed to setup GSI :%d, err_code:%d\n", 134 gsi, rc); 135 } 136 137 return irq; 138 } 139 140 static int acpi_register_gsi_xen(struct device *dev, u32 gsi, 141 int trigger, int polarity) 142 { 143 return xen_register_gsi(gsi, -1 /* no GSI override */, trigger, polarity); 144 } 145 #endif 146 #endif 147 148 #if defined(CONFIG_PCI_MSI) 149 #include <linux/msi.h> 150 #include <asm/msidef.h> 151 152 struct xen_pci_frontend_ops *xen_pci_frontend; 153 EXPORT_SYMBOL_GPL(xen_pci_frontend); 154 155 static int xen_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) 156 { 157 int irq, ret, i; 158 struct msi_desc *msidesc; 159 int *v; 160 161 v = kzalloc(sizeof(int) * max(1, nvec), GFP_KERNEL); 162 if (!v) 163 return -ENOMEM; 164 165 if (type == PCI_CAP_ID_MSIX) 166 ret = xen_pci_frontend_enable_msix(dev, v, nvec); 167 else 168 ret = xen_pci_frontend_enable_msi(dev, v); 169 if (ret) 170 goto error; 171 i = 0; 172 list_for_each_entry(msidesc, &dev->msi_list, list) { 173 irq = xen_bind_pirq_msi_to_irq(dev, msidesc, v[i], 0, 174 (type == PCI_CAP_ID_MSIX) ? 175 "pcifront-msi-x" : 176 "pcifront-msi", 177 DOMID_SELF); 178 if (irq < 0) 179 goto free; 180 i++; 181 } 182 kfree(v); 183 return 0; 184 185 error: 186 dev_err(&dev->dev, "Xen PCI frontend has not registered MSI/MSI-X support!\n"); 187 free: 188 kfree(v); 189 return ret; 190 } 191 192 #define XEN_PIRQ_MSI_DATA (MSI_DATA_TRIGGER_EDGE | \ 193 MSI_DATA_LEVEL_ASSERT | (3 << 8) | MSI_DATA_VECTOR(0)) 194 195 static void xen_msi_compose_msg(struct pci_dev *pdev, unsigned int pirq, 196 struct msi_msg *msg) 197 { 198 /* We set vector == 0 to tell the hypervisor we don't care about it, 199 * but we want a pirq setup instead. 200 * We use the dest_id field to pass the pirq that we want. */ 201 msg->address_hi = MSI_ADDR_BASE_HI | MSI_ADDR_EXT_DEST_ID(pirq); 202 msg->address_lo = 203 MSI_ADDR_BASE_LO | 204 MSI_ADDR_DEST_MODE_PHYSICAL | 205 MSI_ADDR_REDIRECTION_CPU | 206 MSI_ADDR_DEST_ID(pirq); 207 208 msg->data = XEN_PIRQ_MSI_DATA; 209 } 210 211 static int xen_hvm_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) 212 { 213 int irq, pirq; 214 struct msi_desc *msidesc; 215 struct msi_msg msg; 216 217 list_for_each_entry(msidesc, &dev->msi_list, list) { 218 __read_msi_msg(msidesc, &msg); 219 pirq = MSI_ADDR_EXT_DEST_ID(msg.address_hi) | 220 ((msg.address_lo >> MSI_ADDR_DEST_ID_SHIFT) & 0xff); 221 if (msg.data != XEN_PIRQ_MSI_DATA || 222 xen_irq_from_pirq(pirq) < 0) { 223 pirq = xen_allocate_pirq_msi(dev, msidesc); 224 if (pirq < 0) 225 goto error; 226 xen_msi_compose_msg(dev, pirq, &msg); 227 __write_msi_msg(msidesc, &msg); 228 dev_dbg(&dev->dev, "xen: msi bound to pirq=%d\n", pirq); 229 } else { 230 dev_dbg(&dev->dev, 231 "xen: msi already bound to pirq=%d\n", pirq); 232 } 233 irq = xen_bind_pirq_msi_to_irq(dev, msidesc, pirq, 0, 234 (type == PCI_CAP_ID_MSIX) ? 235 "msi-x" : "msi", 236 DOMID_SELF); 237 if (irq < 0) 238 goto error; 239 dev_dbg(&dev->dev, 240 "xen: msi --> pirq=%d --> irq=%d\n", pirq, irq); 241 } 242 return 0; 243 244 error: 245 dev_err(&dev->dev, 246 "Xen PCI frontend has not registered MSI/MSI-X support!\n"); 247 return -ENODEV; 248 } 249 250 #ifdef CONFIG_XEN_DOM0 251 static int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) 252 { 253 int ret = 0; 254 struct msi_desc *msidesc; 255 256 list_for_each_entry(msidesc, &dev->msi_list, list) { 257 struct physdev_map_pirq map_irq; 258 domid_t domid; 259 260 domid = ret = xen_find_device_domain_owner(dev); 261 /* N.B. Casting int's -ENODEV to uint16_t results in 0xFFED, 262 * hence check ret value for < 0. */ 263 if (ret < 0) 264 domid = DOMID_SELF; 265 266 memset(&map_irq, 0, sizeof(map_irq)); 267 map_irq.domid = domid; 268 map_irq.type = MAP_PIRQ_TYPE_MSI; 269 map_irq.index = -1; 270 map_irq.pirq = -1; 271 map_irq.bus = dev->bus->number; 272 map_irq.devfn = dev->devfn; 273 274 if (type == PCI_CAP_ID_MSIX) { 275 int pos; 276 u32 table_offset, bir; 277 278 pos = pci_find_capability(dev, PCI_CAP_ID_MSIX); 279 280 pci_read_config_dword(dev, pos + PCI_MSIX_TABLE, 281 &table_offset); 282 bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK); 283 284 map_irq.table_base = pci_resource_start(dev, bir); 285 map_irq.entry_nr = msidesc->msi_attrib.entry_nr; 286 } 287 288 ret = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq); 289 if (ret) { 290 dev_warn(&dev->dev, "xen map irq failed %d for %d domain\n", 291 ret, domid); 292 goto out; 293 } 294 295 ret = xen_bind_pirq_msi_to_irq(dev, msidesc, 296 map_irq.pirq, map_irq.index, 297 (type == PCI_CAP_ID_MSIX) ? 298 "msi-x" : "msi", 299 domid); 300 if (ret < 0) 301 goto out; 302 } 303 ret = 0; 304 out: 305 return ret; 306 } 307 #endif 308 309 static void xen_teardown_msi_irqs(struct pci_dev *dev) 310 { 311 struct msi_desc *msidesc; 312 313 msidesc = list_entry(dev->msi_list.next, struct msi_desc, list); 314 if (msidesc->msi_attrib.is_msix) 315 xen_pci_frontend_disable_msix(dev); 316 else 317 xen_pci_frontend_disable_msi(dev); 318 319 /* Free the IRQ's and the msidesc using the generic code. */ 320 default_teardown_msi_irqs(dev); 321 } 322 323 static void xen_teardown_msi_irq(unsigned int irq) 324 { 325 xen_destroy_irq(irq); 326 } 327 328 #endif 329 330 int __init pci_xen_init(void) 331 { 332 if (!xen_pv_domain() || xen_initial_domain()) 333 return -ENODEV; 334 335 printk(KERN_INFO "PCI: setting up Xen PCI frontend stub\n"); 336 337 pcibios_set_cache_line_size(); 338 339 pcibios_enable_irq = xen_pcifront_enable_irq; 340 pcibios_disable_irq = NULL; 341 342 #ifdef CONFIG_ACPI 343 /* Keep ACPI out of the picture */ 344 acpi_noirq = 1; 345 #endif 346 347 #ifdef CONFIG_PCI_MSI 348 x86_msi.setup_msi_irqs = xen_setup_msi_irqs; 349 x86_msi.teardown_msi_irq = xen_teardown_msi_irq; 350 x86_msi.teardown_msi_irqs = xen_teardown_msi_irqs; 351 #endif 352 return 0; 353 } 354 355 int __init pci_xen_hvm_init(void) 356 { 357 if (!xen_feature(XENFEAT_hvm_pirqs)) 358 return 0; 359 360 #ifdef CONFIG_ACPI 361 /* 362 * We don't want to change the actual ACPI delivery model, 363 * just how GSIs get registered. 364 */ 365 __acpi_register_gsi = acpi_register_gsi_xen_hvm; 366 #endif 367 368 #ifdef CONFIG_PCI_MSI 369 x86_msi.setup_msi_irqs = xen_hvm_setup_msi_irqs; 370 x86_msi.teardown_msi_irq = xen_teardown_msi_irq; 371 #endif 372 return 0; 373 } 374 375 #ifdef CONFIG_XEN_DOM0 376 static __init void xen_setup_acpi_sci(void) 377 { 378 int rc; 379 int trigger, polarity; 380 int gsi = acpi_sci_override_gsi; 381 int irq = -1; 382 int gsi_override = -1; 383 384 if (!gsi) 385 return; 386 387 rc = acpi_get_override_irq(gsi, &trigger, &polarity); 388 if (rc) { 389 printk(KERN_WARNING "xen: acpi_get_override_irq failed for acpi" 390 " sci, rc=%d\n", rc); 391 return; 392 } 393 trigger = trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE; 394 polarity = polarity ? ACPI_ACTIVE_LOW : ACPI_ACTIVE_HIGH; 395 396 printk(KERN_INFO "xen: sci override: global_irq=%d trigger=%d " 397 "polarity=%d\n", gsi, trigger, polarity); 398 399 /* Before we bind the GSI to a Linux IRQ, check whether 400 * we need to override it with bus_irq (IRQ) value. Usually for 401 * IRQs below IRQ_LEGACY_IRQ this holds IRQ == GSI, as so: 402 * ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 low level) 403 * but there are oddballs where the IRQ != GSI: 404 * ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 20 low level) 405 * which ends up being: gsi_to_irq[9] == 20 406 * (which is what acpi_gsi_to_irq ends up calling when starting the 407 * the ACPI interpreter and keels over since IRQ 9 has not been 408 * setup as we had setup IRQ 20 for it). 409 */ 410 if (acpi_gsi_to_irq(gsi, &irq) == 0) { 411 /* Use the provided value if it's valid. */ 412 if (irq >= 0) 413 gsi_override = irq; 414 } 415 416 gsi = xen_register_gsi(gsi, gsi_override, trigger, polarity); 417 printk(KERN_INFO "xen: acpi sci %d\n", gsi); 418 419 return; 420 } 421 422 int __init pci_xen_initial_domain(void) 423 { 424 int irq; 425 426 #ifdef CONFIG_PCI_MSI 427 x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs; 428 x86_msi.teardown_msi_irq = xen_teardown_msi_irq; 429 #endif 430 xen_setup_acpi_sci(); 431 __acpi_register_gsi = acpi_register_gsi_xen; 432 /* Pre-allocate legacy irqs */ 433 for (irq = 0; irq < NR_IRQS_LEGACY; irq++) { 434 int trigger, polarity; 435 436 if (acpi_get_override_irq(irq, &trigger, &polarity) == -1) 437 continue; 438 439 xen_register_pirq(irq, -1 /* no GSI override */, 440 trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE, 441 true /* Map GSI to PIRQ */); 442 } 443 if (0 == nr_ioapics) { 444 for (irq = 0; irq < NR_IRQS_LEGACY; irq++) 445 xen_bind_pirq_gsi_to_irq(irq, irq, 0, "xt-pic"); 446 } 447 return 0; 448 } 449 450 struct xen_device_domain_owner { 451 domid_t domain; 452 struct pci_dev *dev; 453 struct list_head list; 454 }; 455 456 static DEFINE_SPINLOCK(dev_domain_list_spinlock); 457 static struct list_head dev_domain_list = LIST_HEAD_INIT(dev_domain_list); 458 459 static struct xen_device_domain_owner *find_device(struct pci_dev *dev) 460 { 461 struct xen_device_domain_owner *owner; 462 463 list_for_each_entry(owner, &dev_domain_list, list) { 464 if (owner->dev == dev) 465 return owner; 466 } 467 return NULL; 468 } 469 470 int xen_find_device_domain_owner(struct pci_dev *dev) 471 { 472 struct xen_device_domain_owner *owner; 473 int domain = -ENODEV; 474 475 spin_lock(&dev_domain_list_spinlock); 476 owner = find_device(dev); 477 if (owner) 478 domain = owner->domain; 479 spin_unlock(&dev_domain_list_spinlock); 480 return domain; 481 } 482 EXPORT_SYMBOL_GPL(xen_find_device_domain_owner); 483 484 int xen_register_device_domain_owner(struct pci_dev *dev, uint16_t domain) 485 { 486 struct xen_device_domain_owner *owner; 487 488 owner = kzalloc(sizeof(struct xen_device_domain_owner), GFP_KERNEL); 489 if (!owner) 490 return -ENODEV; 491 492 spin_lock(&dev_domain_list_spinlock); 493 if (find_device(dev)) { 494 spin_unlock(&dev_domain_list_spinlock); 495 kfree(owner); 496 return -EEXIST; 497 } 498 owner->domain = domain; 499 owner->dev = dev; 500 list_add_tail(&owner->list, &dev_domain_list); 501 spin_unlock(&dev_domain_list_spinlock); 502 return 0; 503 } 504 EXPORT_SYMBOL_GPL(xen_register_device_domain_owner); 505 506 int xen_unregister_device_domain_owner(struct pci_dev *dev) 507 { 508 struct xen_device_domain_owner *owner; 509 510 spin_lock(&dev_domain_list_spinlock); 511 owner = find_device(dev); 512 if (!owner) { 513 spin_unlock(&dev_domain_list_spinlock); 514 return -ENODEV; 515 } 516 list_del(&owner->list); 517 spin_unlock(&dev_domain_list_spinlock); 518 kfree(owner); 519 return 0; 520 } 521 EXPORT_SYMBOL_GPL(xen_unregister_device_domain_owner); 522 #endif 523