1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * PCI Hotplug Driver for PowerPC PowerNV platform. 4 * 5 * Copyright Gavin Shan, IBM Corporation 2016. 6 */ 7 8 #include <linux/libfdt.h> 9 #include <linux/module.h> 10 #include <linux/pci.h> 11 #include <linux/pci_hotplug.h> 12 13 #include <asm/opal.h> 14 #include <asm/pnv-pci.h> 15 #include <asm/ppc-pci.h> 16 17 #define DRIVER_VERSION "0.1" 18 #define DRIVER_AUTHOR "Gavin Shan, IBM Corporation" 19 #define DRIVER_DESC "PowerPC PowerNV PCI Hotplug Driver" 20 21 struct pnv_php_event { 22 bool added; 23 struct pnv_php_slot *php_slot; 24 struct work_struct work; 25 }; 26 27 static LIST_HEAD(pnv_php_slot_list); 28 static DEFINE_SPINLOCK(pnv_php_lock); 29 30 static void pnv_php_register(struct device_node *dn); 31 static void pnv_php_unregister_one(struct device_node *dn); 32 static void pnv_php_unregister(struct device_node *dn); 33 34 static void pnv_php_disable_irq(struct pnv_php_slot *php_slot, 35 bool disable_device) 36 { 37 struct pci_dev *pdev = php_slot->pdev; 38 int irq = php_slot->irq; 39 u16 ctrl; 40 41 if (php_slot->irq > 0) { 42 pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &ctrl); 43 ctrl &= ~(PCI_EXP_SLTCTL_HPIE | 44 PCI_EXP_SLTCTL_PDCE | 45 PCI_EXP_SLTCTL_DLLSCE); 46 pcie_capability_write_word(pdev, PCI_EXP_SLTCTL, ctrl); 47 48 free_irq(php_slot->irq, php_slot); 49 php_slot->irq = 0; 50 } 51 52 if (php_slot->wq) { 53 destroy_workqueue(php_slot->wq); 54 php_slot->wq = NULL; 55 } 56 57 if (disable_device || irq > 0) { 58 if (pdev->msix_enabled) 59 pci_disable_msix(pdev); 60 else if (pdev->msi_enabled) 61 pci_disable_msi(pdev); 62 63 pci_disable_device(pdev); 64 } 65 } 66 67 static void pnv_php_free_slot(struct kref *kref) 68 { 69 struct pnv_php_slot *php_slot = container_of(kref, 70 struct pnv_php_slot, kref); 71 72 WARN_ON(!list_empty(&php_slot->children)); 73 pnv_php_disable_irq(php_slot, false); 74 kfree(php_slot->name); 75 kfree(php_slot); 76 } 77 78 static inline void pnv_php_put_slot(struct pnv_php_slot *php_slot) 79 { 80 81 if (!php_slot) 82 return; 83 84 kref_put(&php_slot->kref, pnv_php_free_slot); 85 } 86 87 static struct pnv_php_slot *pnv_php_match(struct device_node *dn, 88 struct pnv_php_slot *php_slot) 89 { 90 struct pnv_php_slot *target, *tmp; 91 92 if (php_slot->dn == dn) { 93 kref_get(&php_slot->kref); 94 return php_slot; 95 } 96 97 list_for_each_entry(tmp, &php_slot->children, link) { 98 target = pnv_php_match(dn, tmp); 99 if (target) 100 return target; 101 } 102 103 return NULL; 104 } 105 106 struct pnv_php_slot *pnv_php_find_slot(struct device_node *dn) 107 { 108 struct pnv_php_slot *php_slot, *tmp; 109 unsigned long flags; 110 111 spin_lock_irqsave(&pnv_php_lock, flags); 112 list_for_each_entry(tmp, &pnv_php_slot_list, link) { 113 php_slot = pnv_php_match(dn, tmp); 114 if (php_slot) { 115 spin_unlock_irqrestore(&pnv_php_lock, flags); 116 return php_slot; 117 } 118 } 119 spin_unlock_irqrestore(&pnv_php_lock, flags); 120 121 return NULL; 122 } 123 EXPORT_SYMBOL_GPL(pnv_php_find_slot); 124 125 /* 126 * Remove pdn for all children of the indicated device node. 127 * The function should remove pdn in a depth-first manner. 128 */ 129 static void pnv_php_rmv_pdns(struct device_node *dn) 130 { 131 struct device_node *child; 132 133 for_each_child_of_node(dn, child) { 134 pnv_php_rmv_pdns(child); 135 136 pci_remove_device_node_info(child); 137 } 138 } 139 140 /* 141 * Detach all child nodes of the indicated device nodes. The 142 * function should handle device nodes in depth-first manner. 143 * 144 * We should not invoke of_node_release() as the memory for 145 * individual device node is part of large memory block. The 146 * large block is allocated from memblock (system bootup) or 147 * kmalloc() when unflattening the device tree by OF changeset. 148 * We can not free the large block allocated from memblock. For 149 * later case, it should be released at once. 150 */ 151 static void pnv_php_detach_device_nodes(struct device_node *parent) 152 { 153 struct device_node *dn; 154 int refcount; 155 156 for_each_child_of_node(parent, dn) { 157 pnv_php_detach_device_nodes(dn); 158 159 of_node_put(dn); 160 refcount = kref_read(&dn->kobj.kref); 161 if (refcount != 1) 162 pr_warn("Invalid refcount %d on <%pOF>\n", 163 refcount, dn); 164 165 of_detach_node(dn); 166 } 167 } 168 169 static void pnv_php_rmv_devtree(struct pnv_php_slot *php_slot) 170 { 171 pnv_php_rmv_pdns(php_slot->dn); 172 173 /* 174 * Decrease the refcount if the device nodes were created 175 * through OF changeset before detaching them. 176 */ 177 if (php_slot->fdt) 178 of_changeset_destroy(&php_slot->ocs); 179 pnv_php_detach_device_nodes(php_slot->dn); 180 181 if (php_slot->fdt) { 182 kfree(php_slot->dt); 183 kfree(php_slot->fdt); 184 php_slot->dt = NULL; 185 php_slot->dn->child = NULL; 186 php_slot->fdt = NULL; 187 } 188 } 189 190 /* 191 * As the nodes in OF changeset are applied in reverse order, we 192 * need revert the nodes in advance so that we have correct node 193 * order after the changeset is applied. 194 */ 195 static void pnv_php_reverse_nodes(struct device_node *parent) 196 { 197 struct device_node *child, *next; 198 199 /* In-depth first */ 200 for_each_child_of_node(parent, child) 201 pnv_php_reverse_nodes(child); 202 203 /* Reverse the nodes in the child list */ 204 child = parent->child; 205 parent->child = NULL; 206 while (child) { 207 next = child->sibling; 208 209 child->sibling = parent->child; 210 parent->child = child; 211 child = next; 212 } 213 } 214 215 static int pnv_php_populate_changeset(struct of_changeset *ocs, 216 struct device_node *dn) 217 { 218 struct device_node *child; 219 int ret = 0; 220 221 for_each_child_of_node(dn, child) { 222 ret = of_changeset_attach_node(ocs, child); 223 if (ret) { 224 of_node_put(child); 225 break; 226 } 227 228 ret = pnv_php_populate_changeset(ocs, child); 229 if (ret) { 230 of_node_put(child); 231 break; 232 } 233 } 234 235 return ret; 236 } 237 238 static void *pnv_php_add_one_pdn(struct device_node *dn, void *data) 239 { 240 struct pci_controller *hose = (struct pci_controller *)data; 241 struct pci_dn *pdn; 242 243 pdn = pci_add_device_node_info(hose, dn); 244 if (!pdn) 245 return ERR_PTR(-ENOMEM); 246 247 return NULL; 248 } 249 250 static void pnv_php_add_pdns(struct pnv_php_slot *slot) 251 { 252 struct pci_controller *hose = pci_bus_to_host(slot->bus); 253 254 pci_traverse_device_nodes(slot->dn, pnv_php_add_one_pdn, hose); 255 } 256 257 static int pnv_php_add_devtree(struct pnv_php_slot *php_slot) 258 { 259 void *fdt, *fdt1, *dt; 260 int ret; 261 262 /* We don't know the FDT blob size. We try to get it through 263 * maximal memory chunk and then copy it to another chunk that 264 * fits the real size. 265 */ 266 fdt1 = kzalloc(0x10000, GFP_KERNEL); 267 if (!fdt1) { 268 ret = -ENOMEM; 269 goto out; 270 } 271 272 ret = pnv_pci_get_device_tree(php_slot->dn->phandle, fdt1, 0x10000); 273 if (ret) { 274 pci_warn(php_slot->pdev, "Error %d getting FDT blob\n", ret); 275 goto free_fdt1; 276 } 277 278 fdt = kzalloc(fdt_totalsize(fdt1), GFP_KERNEL); 279 if (!fdt) { 280 ret = -ENOMEM; 281 goto free_fdt1; 282 } 283 284 /* Unflatten device tree blob */ 285 memcpy(fdt, fdt1, fdt_totalsize(fdt1)); 286 dt = of_fdt_unflatten_tree(fdt, php_slot->dn, NULL); 287 if (!dt) { 288 ret = -EINVAL; 289 pci_warn(php_slot->pdev, "Cannot unflatten FDT\n"); 290 goto free_fdt; 291 } 292 293 /* Initialize and apply the changeset */ 294 of_changeset_init(&php_slot->ocs); 295 pnv_php_reverse_nodes(php_slot->dn); 296 ret = pnv_php_populate_changeset(&php_slot->ocs, php_slot->dn); 297 if (ret) { 298 pnv_php_reverse_nodes(php_slot->dn); 299 pci_warn(php_slot->pdev, "Error %d populating changeset\n", 300 ret); 301 goto free_dt; 302 } 303 304 php_slot->dn->child = NULL; 305 ret = of_changeset_apply(&php_slot->ocs); 306 if (ret) { 307 pci_warn(php_slot->pdev, "Error %d applying changeset\n", ret); 308 goto destroy_changeset; 309 } 310 311 /* Add device node firmware data */ 312 pnv_php_add_pdns(php_slot); 313 php_slot->fdt = fdt; 314 php_slot->dt = dt; 315 kfree(fdt1); 316 goto out; 317 318 destroy_changeset: 319 of_changeset_destroy(&php_slot->ocs); 320 free_dt: 321 kfree(dt); 322 php_slot->dn->child = NULL; 323 free_fdt: 324 kfree(fdt); 325 free_fdt1: 326 kfree(fdt1); 327 out: 328 return ret; 329 } 330 331 int pnv_php_set_slot_power_state(struct hotplug_slot *slot, 332 uint8_t state) 333 { 334 struct pnv_php_slot *php_slot = slot->private; 335 struct opal_msg msg; 336 int ret; 337 338 ret = pnv_pci_set_power_state(php_slot->id, state, &msg); 339 if (ret > 0) { 340 if (be64_to_cpu(msg.params[1]) != php_slot->dn->phandle || 341 be64_to_cpu(msg.params[2]) != state || 342 be64_to_cpu(msg.params[3]) != OPAL_SUCCESS) { 343 pci_warn(php_slot->pdev, "Wrong msg (%lld, %lld, %lld)\n", 344 be64_to_cpu(msg.params[1]), 345 be64_to_cpu(msg.params[2]), 346 be64_to_cpu(msg.params[3])); 347 return -ENOMSG; 348 } 349 } else if (ret < 0) { 350 pci_warn(php_slot->pdev, "Error %d powering %s\n", 351 ret, (state == OPAL_PCI_SLOT_POWER_ON) ? "on" : "off"); 352 return ret; 353 } 354 355 if (state == OPAL_PCI_SLOT_POWER_OFF || state == OPAL_PCI_SLOT_OFFLINE) 356 pnv_php_rmv_devtree(php_slot); 357 else 358 ret = pnv_php_add_devtree(php_slot); 359 360 return ret; 361 } 362 EXPORT_SYMBOL_GPL(pnv_php_set_slot_power_state); 363 364 static int pnv_php_get_power_state(struct hotplug_slot *slot, u8 *state) 365 { 366 struct pnv_php_slot *php_slot = slot->private; 367 uint8_t power_state = OPAL_PCI_SLOT_POWER_ON; 368 int ret; 369 370 /* 371 * Retrieve power status from firmware. If we fail 372 * getting that, the power status fails back to 373 * be on. 374 */ 375 ret = pnv_pci_get_power_state(php_slot->id, &power_state); 376 if (ret) { 377 pci_warn(php_slot->pdev, "Error %d getting power status\n", 378 ret); 379 } else { 380 *state = power_state; 381 slot->info->power_status = power_state; 382 } 383 384 return 0; 385 } 386 387 static int pnv_php_get_adapter_state(struct hotplug_slot *slot, u8 *state) 388 { 389 struct pnv_php_slot *php_slot = slot->private; 390 uint8_t presence = OPAL_PCI_SLOT_EMPTY; 391 int ret; 392 393 /* 394 * Retrieve presence status from firmware. If we can't 395 * get that, it will fail back to be empty. 396 */ 397 ret = pnv_pci_get_presence_state(php_slot->id, &presence); 398 if (ret >= 0) { 399 *state = presence; 400 slot->info->adapter_status = presence; 401 ret = 0; 402 } else { 403 pci_warn(php_slot->pdev, "Error %d getting presence\n", ret); 404 } 405 406 return ret; 407 } 408 409 static int pnv_php_set_attention_state(struct hotplug_slot *slot, u8 state) 410 { 411 /* FIXME: Make it real once firmware supports it */ 412 slot->info->attention_status = state; 413 414 return 0; 415 } 416 417 static int pnv_php_enable(struct pnv_php_slot *php_slot, bool rescan) 418 { 419 struct hotplug_slot *slot = &php_slot->slot; 420 uint8_t presence = OPAL_PCI_SLOT_EMPTY; 421 uint8_t power_status = OPAL_PCI_SLOT_POWER_ON; 422 int ret; 423 424 /* Check if the slot has been configured */ 425 if (php_slot->state != PNV_PHP_STATE_REGISTERED) 426 return 0; 427 428 /* Retrieve slot presence status */ 429 ret = pnv_php_get_adapter_state(slot, &presence); 430 if (ret) 431 return ret; 432 433 /* 434 * Proceed if there have nothing behind the slot. However, 435 * we should leave the slot in registered state at the 436 * beginning. Otherwise, the PCI devices inserted afterwards 437 * won't be probed and populated. 438 */ 439 if (presence == OPAL_PCI_SLOT_EMPTY) { 440 if (!php_slot->power_state_check) { 441 php_slot->power_state_check = true; 442 443 return 0; 444 } 445 446 goto scan; 447 } 448 449 /* 450 * If the power supply to the slot is off, we can't detect 451 * adapter presence state. That means we have to turn the 452 * slot on before going to probe slot's presence state. 453 * 454 * On the first time, we don't change the power status to 455 * boost system boot with assumption that the firmware 456 * supplies consistent slot power status: empty slot always 457 * has its power off and non-empty slot has its power on. 458 */ 459 if (!php_slot->power_state_check) { 460 php_slot->power_state_check = true; 461 462 ret = pnv_php_get_power_state(slot, &power_status); 463 if (ret) 464 return ret; 465 466 if (power_status != OPAL_PCI_SLOT_POWER_ON) 467 return 0; 468 } 469 470 /* Check the power status. Scan the slot if it is already on */ 471 ret = pnv_php_get_power_state(slot, &power_status); 472 if (ret) 473 return ret; 474 475 if (power_status == OPAL_PCI_SLOT_POWER_ON) 476 goto scan; 477 478 /* Power is off, turn it on and then scan the slot */ 479 ret = pnv_php_set_slot_power_state(slot, OPAL_PCI_SLOT_POWER_ON); 480 if (ret) 481 return ret; 482 483 scan: 484 if (presence == OPAL_PCI_SLOT_PRESENT) { 485 if (rescan) { 486 pci_lock_rescan_remove(); 487 pci_hp_add_devices(php_slot->bus); 488 pci_unlock_rescan_remove(); 489 } 490 491 /* Rescan for child hotpluggable slots */ 492 php_slot->state = PNV_PHP_STATE_POPULATED; 493 if (rescan) 494 pnv_php_register(php_slot->dn); 495 } else { 496 php_slot->state = PNV_PHP_STATE_POPULATED; 497 } 498 499 return 0; 500 } 501 502 static int pnv_php_enable_slot(struct hotplug_slot *slot) 503 { 504 struct pnv_php_slot *php_slot = container_of(slot, 505 struct pnv_php_slot, slot); 506 507 return pnv_php_enable(php_slot, true); 508 } 509 510 static int pnv_php_disable_slot(struct hotplug_slot *slot) 511 { 512 struct pnv_php_slot *php_slot = slot->private; 513 int ret; 514 515 if (php_slot->state != PNV_PHP_STATE_POPULATED) 516 return 0; 517 518 /* Remove all devices behind the slot */ 519 pci_lock_rescan_remove(); 520 pci_hp_remove_devices(php_slot->bus); 521 pci_unlock_rescan_remove(); 522 523 /* Detach the child hotpluggable slots */ 524 pnv_php_unregister(php_slot->dn); 525 526 /* Notify firmware and remove device nodes */ 527 ret = pnv_php_set_slot_power_state(slot, OPAL_PCI_SLOT_POWER_OFF); 528 529 php_slot->state = PNV_PHP_STATE_REGISTERED; 530 return ret; 531 } 532 533 static struct hotplug_slot_ops php_slot_ops = { 534 .get_power_status = pnv_php_get_power_state, 535 .get_adapter_status = pnv_php_get_adapter_state, 536 .set_attention_status = pnv_php_set_attention_state, 537 .enable_slot = pnv_php_enable_slot, 538 .disable_slot = pnv_php_disable_slot, 539 }; 540 541 static void pnv_php_release(struct pnv_php_slot *php_slot) 542 { 543 unsigned long flags; 544 545 /* Remove from global or child list */ 546 spin_lock_irqsave(&pnv_php_lock, flags); 547 list_del(&php_slot->link); 548 spin_unlock_irqrestore(&pnv_php_lock, flags); 549 550 /* Detach from parent */ 551 pnv_php_put_slot(php_slot); 552 pnv_php_put_slot(php_slot->parent); 553 } 554 555 static struct pnv_php_slot *pnv_php_alloc_slot(struct device_node *dn) 556 { 557 struct pnv_php_slot *php_slot; 558 struct pci_bus *bus; 559 const char *label; 560 uint64_t id; 561 int ret; 562 563 ret = of_property_read_string(dn, "ibm,slot-label", &label); 564 if (ret) 565 return NULL; 566 567 if (pnv_pci_get_slot_id(dn, &id)) 568 return NULL; 569 570 bus = pci_find_bus_by_node(dn); 571 if (!bus) 572 return NULL; 573 574 php_slot = kzalloc(sizeof(*php_slot), GFP_KERNEL); 575 if (!php_slot) 576 return NULL; 577 578 php_slot->name = kstrdup(label, GFP_KERNEL); 579 if (!php_slot->name) { 580 kfree(php_slot); 581 return NULL; 582 } 583 584 if (dn->child && PCI_DN(dn->child)) 585 php_slot->slot_no = PCI_SLOT(PCI_DN(dn->child)->devfn); 586 else 587 php_slot->slot_no = -1; /* Placeholder slot */ 588 589 kref_init(&php_slot->kref); 590 php_slot->state = PNV_PHP_STATE_INITIALIZED; 591 php_slot->dn = dn; 592 php_slot->pdev = bus->self; 593 php_slot->bus = bus; 594 php_slot->id = id; 595 php_slot->power_state_check = false; 596 php_slot->slot.ops = &php_slot_ops; 597 php_slot->slot.info = &php_slot->slot_info; 598 php_slot->slot.private = php_slot; 599 600 INIT_LIST_HEAD(&php_slot->children); 601 INIT_LIST_HEAD(&php_slot->link); 602 603 return php_slot; 604 } 605 606 static int pnv_php_register_slot(struct pnv_php_slot *php_slot) 607 { 608 struct pnv_php_slot *parent; 609 struct device_node *dn = php_slot->dn; 610 unsigned long flags; 611 int ret; 612 613 /* Check if the slot is registered or not */ 614 parent = pnv_php_find_slot(php_slot->dn); 615 if (parent) { 616 pnv_php_put_slot(parent); 617 return -EEXIST; 618 } 619 620 /* Register PCI slot */ 621 ret = pci_hp_register(&php_slot->slot, php_slot->bus, 622 php_slot->slot_no, php_slot->name); 623 if (ret) { 624 pci_warn(php_slot->pdev, "Error %d registering slot\n", ret); 625 return ret; 626 } 627 628 /* Attach to the parent's child list or global list */ 629 while ((dn = of_get_parent(dn))) { 630 if (!PCI_DN(dn)) { 631 of_node_put(dn); 632 break; 633 } 634 635 parent = pnv_php_find_slot(dn); 636 if (parent) { 637 of_node_put(dn); 638 break; 639 } 640 641 of_node_put(dn); 642 } 643 644 spin_lock_irqsave(&pnv_php_lock, flags); 645 php_slot->parent = parent; 646 if (parent) 647 list_add_tail(&php_slot->link, &parent->children); 648 else 649 list_add_tail(&php_slot->link, &pnv_php_slot_list); 650 spin_unlock_irqrestore(&pnv_php_lock, flags); 651 652 php_slot->state = PNV_PHP_STATE_REGISTERED; 653 return 0; 654 } 655 656 static int pnv_php_enable_msix(struct pnv_php_slot *php_slot) 657 { 658 struct pci_dev *pdev = php_slot->pdev; 659 struct msix_entry entry; 660 int nr_entries, ret; 661 u16 pcie_flag; 662 663 /* Get total number of MSIx entries */ 664 nr_entries = pci_msix_vec_count(pdev); 665 if (nr_entries < 0) 666 return nr_entries; 667 668 /* Check hotplug MSIx entry is in range */ 669 pcie_capability_read_word(pdev, PCI_EXP_FLAGS, &pcie_flag); 670 entry.entry = (pcie_flag & PCI_EXP_FLAGS_IRQ) >> 9; 671 if (entry.entry >= nr_entries) 672 return -ERANGE; 673 674 /* Enable MSIx */ 675 ret = pci_enable_msix_exact(pdev, &entry, 1); 676 if (ret) { 677 pci_warn(pdev, "Error %d enabling MSIx\n", ret); 678 return ret; 679 } 680 681 return entry.vector; 682 } 683 684 static void pnv_php_event_handler(struct work_struct *work) 685 { 686 struct pnv_php_event *event = 687 container_of(work, struct pnv_php_event, work); 688 struct pnv_php_slot *php_slot = event->php_slot; 689 690 if (event->added) 691 pnv_php_enable_slot(&php_slot->slot); 692 else 693 pnv_php_disable_slot(&php_slot->slot); 694 695 kfree(event); 696 } 697 698 static irqreturn_t pnv_php_interrupt(int irq, void *data) 699 { 700 struct pnv_php_slot *php_slot = data; 701 struct pci_dev *pchild, *pdev = php_slot->pdev; 702 struct eeh_dev *edev; 703 struct eeh_pe *pe; 704 struct pnv_php_event *event; 705 u16 sts, lsts; 706 u8 presence; 707 bool added; 708 unsigned long flags; 709 int ret; 710 711 pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &sts); 712 sts &= (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC); 713 pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, sts); 714 if (sts & PCI_EXP_SLTSTA_DLLSC) { 715 pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lsts); 716 added = !!(lsts & PCI_EXP_LNKSTA_DLLLA); 717 } else if (!(php_slot->flags & PNV_PHP_FLAG_BROKEN_PDC) && 718 (sts & PCI_EXP_SLTSTA_PDC)) { 719 ret = pnv_pci_get_presence_state(php_slot->id, &presence); 720 if (ret) { 721 pci_warn(pdev, "PCI slot [%s] error %d getting presence (0x%04x), to retry the operation.\n", 722 php_slot->name, ret, sts); 723 return IRQ_HANDLED; 724 } 725 726 added = !!(presence == OPAL_PCI_SLOT_PRESENT); 727 } else { 728 return IRQ_NONE; 729 } 730 731 /* Freeze the removed PE to avoid unexpected error reporting */ 732 if (!added) { 733 pchild = list_first_entry_or_null(&php_slot->bus->devices, 734 struct pci_dev, bus_list); 735 edev = pchild ? pci_dev_to_eeh_dev(pchild) : NULL; 736 pe = edev ? edev->pe : NULL; 737 if (pe) { 738 eeh_serialize_lock(&flags); 739 eeh_pe_state_mark(pe, EEH_PE_ISOLATED); 740 eeh_serialize_unlock(flags); 741 eeh_pe_set_option(pe, EEH_OPT_FREEZE_PE); 742 } 743 } 744 745 /* 746 * The PE is left in frozen state if the event is missed. It's 747 * fine as the PCI devices (PE) aren't functional any more. 748 */ 749 event = kzalloc(sizeof(*event), GFP_ATOMIC); 750 if (!event) { 751 pci_warn(pdev, "PCI slot [%s] missed hotplug event 0x%04x\n", 752 php_slot->name, sts); 753 return IRQ_HANDLED; 754 } 755 756 pci_info(pdev, "PCI slot [%s] %s (IRQ: %d)\n", 757 php_slot->name, added ? "added" : "removed", irq); 758 INIT_WORK(&event->work, pnv_php_event_handler); 759 event->added = added; 760 event->php_slot = php_slot; 761 queue_work(php_slot->wq, &event->work); 762 763 return IRQ_HANDLED; 764 } 765 766 static void pnv_php_init_irq(struct pnv_php_slot *php_slot, int irq) 767 { 768 struct pci_dev *pdev = php_slot->pdev; 769 u32 broken_pdc = 0; 770 u16 sts, ctrl; 771 int ret; 772 773 /* Allocate workqueue */ 774 php_slot->wq = alloc_workqueue("pciehp-%s", 0, 0, php_slot->name); 775 if (!php_slot->wq) { 776 pci_warn(pdev, "Cannot alloc workqueue\n"); 777 pnv_php_disable_irq(php_slot, true); 778 return; 779 } 780 781 /* Check PDC (Presence Detection Change) is broken or not */ 782 ret = of_property_read_u32(php_slot->dn, "ibm,slot-broken-pdc", 783 &broken_pdc); 784 if (!ret && broken_pdc) 785 php_slot->flags |= PNV_PHP_FLAG_BROKEN_PDC; 786 787 /* Clear pending interrupts */ 788 pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &sts); 789 if (php_slot->flags & PNV_PHP_FLAG_BROKEN_PDC) 790 sts |= PCI_EXP_SLTSTA_DLLSC; 791 else 792 sts |= (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC); 793 pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, sts); 794 795 /* Request the interrupt */ 796 ret = request_irq(irq, pnv_php_interrupt, IRQF_SHARED, 797 php_slot->name, php_slot); 798 if (ret) { 799 pnv_php_disable_irq(php_slot, true); 800 pci_warn(pdev, "Error %d enabling IRQ %d\n", ret, irq); 801 return; 802 } 803 804 /* Enable the interrupts */ 805 pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &ctrl); 806 if (php_slot->flags & PNV_PHP_FLAG_BROKEN_PDC) { 807 ctrl &= ~PCI_EXP_SLTCTL_PDCE; 808 ctrl |= (PCI_EXP_SLTCTL_HPIE | 809 PCI_EXP_SLTCTL_DLLSCE); 810 } else { 811 ctrl |= (PCI_EXP_SLTCTL_HPIE | 812 PCI_EXP_SLTCTL_PDCE | 813 PCI_EXP_SLTCTL_DLLSCE); 814 } 815 pcie_capability_write_word(pdev, PCI_EXP_SLTCTL, ctrl); 816 817 /* The interrupt is initialized successfully when @irq is valid */ 818 php_slot->irq = irq; 819 } 820 821 static void pnv_php_enable_irq(struct pnv_php_slot *php_slot) 822 { 823 struct pci_dev *pdev = php_slot->pdev; 824 int irq, ret; 825 826 /* 827 * The MSI/MSIx interrupt might have been occupied by other 828 * drivers. Don't populate the surprise hotplug capability 829 * in that case. 830 */ 831 if (pci_dev_msi_enabled(pdev)) 832 return; 833 834 ret = pci_enable_device(pdev); 835 if (ret) { 836 pci_warn(pdev, "Error %d enabling device\n", ret); 837 return; 838 } 839 840 pci_set_master(pdev); 841 842 /* Enable MSIx interrupt */ 843 irq = pnv_php_enable_msix(php_slot); 844 if (irq > 0) { 845 pnv_php_init_irq(php_slot, irq); 846 return; 847 } 848 849 /* 850 * Use MSI if MSIx doesn't work. Fail back to legacy INTx 851 * if MSI doesn't work either 852 */ 853 ret = pci_enable_msi(pdev); 854 if (!ret || pdev->irq) { 855 irq = pdev->irq; 856 pnv_php_init_irq(php_slot, irq); 857 } 858 } 859 860 static int pnv_php_register_one(struct device_node *dn) 861 { 862 struct pnv_php_slot *php_slot; 863 u32 prop32; 864 int ret; 865 866 /* Check if it's hotpluggable slot */ 867 ret = of_property_read_u32(dn, "ibm,slot-pluggable", &prop32); 868 if (ret || !prop32) 869 return -ENXIO; 870 871 ret = of_property_read_u32(dn, "ibm,reset-by-firmware", &prop32); 872 if (ret || !prop32) 873 return -ENXIO; 874 875 php_slot = pnv_php_alloc_slot(dn); 876 if (!php_slot) 877 return -ENODEV; 878 879 ret = pnv_php_register_slot(php_slot); 880 if (ret) 881 goto free_slot; 882 883 ret = pnv_php_enable(php_slot, false); 884 if (ret) 885 goto unregister_slot; 886 887 /* Enable interrupt if the slot supports surprise hotplug */ 888 ret = of_property_read_u32(dn, "ibm,slot-surprise-pluggable", &prop32); 889 if (!ret && prop32) 890 pnv_php_enable_irq(php_slot); 891 892 return 0; 893 894 unregister_slot: 895 pnv_php_unregister_one(php_slot->dn); 896 free_slot: 897 pnv_php_put_slot(php_slot); 898 return ret; 899 } 900 901 static void pnv_php_register(struct device_node *dn) 902 { 903 struct device_node *child; 904 905 /* 906 * The parent slots should be registered before their 907 * child slots. 908 */ 909 for_each_child_of_node(dn, child) { 910 pnv_php_register_one(child); 911 pnv_php_register(child); 912 } 913 } 914 915 static void pnv_php_unregister_one(struct device_node *dn) 916 { 917 struct pnv_php_slot *php_slot; 918 919 php_slot = pnv_php_find_slot(dn); 920 if (!php_slot) 921 return; 922 923 php_slot->state = PNV_PHP_STATE_OFFLINE; 924 pci_hp_deregister(&php_slot->slot); 925 pnv_php_release(php_slot); 926 pnv_php_put_slot(php_slot); 927 } 928 929 static void pnv_php_unregister(struct device_node *dn) 930 { 931 struct device_node *child; 932 933 /* The child slots should go before their parent slots */ 934 for_each_child_of_node(dn, child) { 935 pnv_php_unregister(child); 936 pnv_php_unregister_one(child); 937 } 938 } 939 940 static int __init pnv_php_init(void) 941 { 942 struct device_node *dn; 943 944 pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n"); 945 for_each_compatible_node(dn, NULL, "ibm,ioda2-phb") 946 pnv_php_register(dn); 947 948 return 0; 949 } 950 951 static void __exit pnv_php_exit(void) 952 { 953 struct device_node *dn; 954 955 for_each_compatible_node(dn, NULL, "ibm,ioda2-phb") 956 pnv_php_unregister(dn); 957 } 958 959 module_init(pnv_php_init); 960 module_exit(pnv_php_exit); 961 962 MODULE_VERSION(DRIVER_VERSION); 963 MODULE_LICENSE("GPL v2"); 964 MODULE_AUTHOR(DRIVER_AUTHOR); 965 MODULE_DESCRIPTION(DRIVER_DESC); 966