1 /* 2 * CompactPCI Hot Plug Driver 3 * 4 * Copyright (C) 2002,2005 SOMA Networks, Inc. 5 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com) 6 * Copyright (C) 2001 IBM Corp. 7 * 8 * All rights reserved. 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; either version 2 of the License, or (at 13 * your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, but 16 * WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or 18 * NON INFRINGEMENT. See the GNU General Public License for more 19 * details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, write to the Free Software 23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 24 * 25 * Send feedback to <scottm@somanetworks.com> 26 */ 27 28 #include <linux/module.h> 29 #include <linux/kernel.h> 30 #include <linux/slab.h> 31 #include <linux/pci.h> 32 #include <linux/pci_hotplug.h> 33 #include <linux/init.h> 34 #include <linux/interrupt.h> 35 #include <linux/smp_lock.h> 36 #include <asm/atomic.h> 37 #include <linux/delay.h> 38 #include "cpci_hotplug.h" 39 40 #define DRIVER_AUTHOR "Scott Murray <scottm@somanetworks.com>" 41 #define DRIVER_DESC "CompactPCI Hot Plug Core" 42 43 #define MY_NAME "cpci_hotplug" 44 45 #define dbg(format, arg...) \ 46 do { \ 47 if (cpci_debug) \ 48 printk (KERN_DEBUG "%s: " format "\n", \ 49 MY_NAME , ## arg); \ 50 } while (0) 51 #define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME , ## arg) 52 #define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME , ## arg) 53 #define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME , ## arg) 54 55 /* local variables */ 56 static DECLARE_RWSEM(list_rwsem); 57 static LIST_HEAD(slot_list); 58 static int slots; 59 static atomic_t extracting; 60 int cpci_debug; 61 static struct cpci_hp_controller *controller; 62 static struct semaphore event_semaphore; /* mutex for process loop (up if something to process) */ 63 static struct semaphore thread_exit; /* guard ensure thread has exited before calling it quits */ 64 static int thread_finished = 1; 65 66 static int enable_slot(struct hotplug_slot *slot); 67 static int disable_slot(struct hotplug_slot *slot); 68 static int set_attention_status(struct hotplug_slot *slot, u8 value); 69 static int get_power_status(struct hotplug_slot *slot, u8 * value); 70 static int get_attention_status(struct hotplug_slot *slot, u8 * value); 71 static int get_adapter_status(struct hotplug_slot *slot, u8 * value); 72 static int get_latch_status(struct hotplug_slot *slot, u8 * value); 73 74 static struct hotplug_slot_ops cpci_hotplug_slot_ops = { 75 .owner = THIS_MODULE, 76 .enable_slot = enable_slot, 77 .disable_slot = disable_slot, 78 .set_attention_status = set_attention_status, 79 .get_power_status = get_power_status, 80 .get_attention_status = get_attention_status, 81 .get_adapter_status = get_adapter_status, 82 .get_latch_status = get_latch_status, 83 }; 84 85 static int 86 update_latch_status(struct hotplug_slot *hotplug_slot, u8 value) 87 { 88 struct hotplug_slot_info info; 89 90 memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info)); 91 info.latch_status = value; 92 return pci_hp_change_slot_info(hotplug_slot, &info); 93 } 94 95 static int 96 update_adapter_status(struct hotplug_slot *hotplug_slot, u8 value) 97 { 98 struct hotplug_slot_info info; 99 100 memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info)); 101 info.adapter_status = value; 102 return pci_hp_change_slot_info(hotplug_slot, &info); 103 } 104 105 static int 106 enable_slot(struct hotplug_slot *hotplug_slot) 107 { 108 struct slot *slot = hotplug_slot->private; 109 int retval = 0; 110 111 dbg("%s - physical_slot = %s", __FUNCTION__, hotplug_slot->name); 112 113 if (controller->ops->set_power) 114 retval = controller->ops->set_power(slot, 1); 115 return retval; 116 } 117 118 static int 119 disable_slot(struct hotplug_slot *hotplug_slot) 120 { 121 struct slot *slot = hotplug_slot->private; 122 int retval = 0; 123 124 dbg("%s - physical_slot = %s", __FUNCTION__, hotplug_slot->name); 125 126 down_write(&list_rwsem); 127 128 /* Unconfigure device */ 129 dbg("%s - unconfiguring slot %s", 130 __FUNCTION__, slot->hotplug_slot->name); 131 if ((retval = cpci_unconfigure_slot(slot))) { 132 err("%s - could not unconfigure slot %s", 133 __FUNCTION__, slot->hotplug_slot->name); 134 goto disable_error; 135 } 136 dbg("%s - finished unconfiguring slot %s", 137 __FUNCTION__, slot->hotplug_slot->name); 138 139 /* Clear EXT (by setting it) */ 140 if (cpci_clear_ext(slot)) { 141 err("%s - could not clear EXT for slot %s", 142 __FUNCTION__, slot->hotplug_slot->name); 143 retval = -ENODEV; 144 goto disable_error; 145 } 146 cpci_led_on(slot); 147 148 if (controller->ops->set_power) 149 if ((retval = controller->ops->set_power(slot, 0))) 150 goto disable_error; 151 152 if (update_adapter_status(slot->hotplug_slot, 0)) 153 warn("failure to update adapter file"); 154 155 if (slot->extracting) { 156 slot->extracting = 0; 157 atomic_dec(&extracting); 158 } 159 disable_error: 160 up_write(&list_rwsem); 161 return retval; 162 } 163 164 static u8 165 cpci_get_power_status(struct slot *slot) 166 { 167 u8 power = 1; 168 169 if (controller->ops->get_power) 170 power = controller->ops->get_power(slot); 171 return power; 172 } 173 174 static int 175 get_power_status(struct hotplug_slot *hotplug_slot, u8 * value) 176 { 177 struct slot *slot = hotplug_slot->private; 178 179 *value = cpci_get_power_status(slot); 180 return 0; 181 } 182 183 static int 184 get_attention_status(struct hotplug_slot *hotplug_slot, u8 * value) 185 { 186 struct slot *slot = hotplug_slot->private; 187 188 *value = cpci_get_attention_status(slot); 189 return 0; 190 } 191 192 static int 193 set_attention_status(struct hotplug_slot *hotplug_slot, u8 status) 194 { 195 return cpci_set_attention_status(hotplug_slot->private, status); 196 } 197 198 static int 199 get_adapter_status(struct hotplug_slot *hotplug_slot, u8 * value) 200 { 201 *value = hotplug_slot->info->adapter_status; 202 return 0; 203 } 204 205 static int 206 get_latch_status(struct hotplug_slot *hotplug_slot, u8 * value) 207 { 208 *value = hotplug_slot->info->latch_status; 209 return 0; 210 } 211 212 static void release_slot(struct hotplug_slot *hotplug_slot) 213 { 214 struct slot *slot = hotplug_slot->private; 215 216 kfree(slot->hotplug_slot->info); 217 kfree(slot->hotplug_slot->name); 218 kfree(slot->hotplug_slot); 219 if (slot->dev) 220 pci_dev_put(slot->dev); 221 kfree(slot); 222 } 223 224 #define SLOT_NAME_SIZE 6 225 static void 226 make_slot_name(struct slot *slot) 227 { 228 snprintf(slot->hotplug_slot->name, 229 SLOT_NAME_SIZE, "%02x:%02x", slot->bus->number, slot->number); 230 } 231 232 int 233 cpci_hp_register_bus(struct pci_bus *bus, u8 first, u8 last) 234 { 235 struct slot *slot; 236 struct hotplug_slot *hotplug_slot; 237 struct hotplug_slot_info *info; 238 char *name; 239 int status = -ENOMEM; 240 int i; 241 242 if (!(controller && bus)) 243 return -ENODEV; 244 245 /* 246 * Create a structure for each slot, and register that slot 247 * with the pci_hotplug subsystem. 248 */ 249 for (i = first; i <= last; ++i) { 250 slot = kzalloc(sizeof (struct slot), GFP_KERNEL); 251 if (!slot) 252 goto error; 253 254 hotplug_slot = 255 kzalloc(sizeof (struct hotplug_slot), GFP_KERNEL); 256 if (!hotplug_slot) 257 goto error_slot; 258 slot->hotplug_slot = hotplug_slot; 259 260 info = kzalloc(sizeof (struct hotplug_slot_info), GFP_KERNEL); 261 if (!info) 262 goto error_hpslot; 263 hotplug_slot->info = info; 264 265 name = kmalloc(SLOT_NAME_SIZE, GFP_KERNEL); 266 if (!name) 267 goto error_info; 268 hotplug_slot->name = name; 269 270 slot->bus = bus; 271 slot->number = i; 272 slot->devfn = PCI_DEVFN(i, 0); 273 274 hotplug_slot->private = slot; 275 hotplug_slot->release = &release_slot; 276 make_slot_name(slot); 277 hotplug_slot->ops = &cpci_hotplug_slot_ops; 278 279 /* 280 * Initialize the slot info structure with some known 281 * good values. 282 */ 283 dbg("initializing slot %s", slot->hotplug_slot->name); 284 info->power_status = cpci_get_power_status(slot); 285 info->attention_status = cpci_get_attention_status(slot); 286 287 dbg("registering slot %s", slot->hotplug_slot->name); 288 status = pci_hp_register(slot->hotplug_slot); 289 if (status) { 290 err("pci_hp_register failed with error %d", status); 291 goto error_name; 292 } 293 294 /* Add slot to our internal list */ 295 down_write(&list_rwsem); 296 list_add(&slot->slot_list, &slot_list); 297 slots++; 298 up_write(&list_rwsem); 299 } 300 return 0; 301 error_name: 302 kfree(name); 303 error_info: 304 kfree(info); 305 error_hpslot: 306 kfree(hotplug_slot); 307 error_slot: 308 kfree(slot); 309 error: 310 return status; 311 } 312 313 int 314 cpci_hp_unregister_bus(struct pci_bus *bus) 315 { 316 struct slot *slot; 317 struct slot *tmp; 318 int status = 0; 319 320 down_write(&list_rwsem); 321 if (!slots) { 322 up_write(&list_rwsem); 323 return -1; 324 } 325 list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) { 326 if (slot->bus == bus) { 327 list_del(&slot->slot_list); 328 slots--; 329 330 dbg("deregistering slot %s", slot->hotplug_slot->name); 331 status = pci_hp_deregister(slot->hotplug_slot); 332 if (status) { 333 err("pci_hp_deregister failed with error %d", 334 status); 335 break; 336 } 337 } 338 } 339 up_write(&list_rwsem); 340 return status; 341 } 342 343 /* This is the interrupt mode interrupt handler */ 344 static irqreturn_t 345 cpci_hp_intr(int irq, void *data) 346 { 347 dbg("entered cpci_hp_intr"); 348 349 /* Check to see if it was our interrupt */ 350 if ((controller->irq_flags & IRQF_SHARED) && 351 !controller->ops->check_irq(controller->dev_id)) { 352 dbg("exited cpci_hp_intr, not our interrupt"); 353 return IRQ_NONE; 354 } 355 356 /* Disable ENUM interrupt */ 357 controller->ops->disable_irq(); 358 359 /* Trigger processing by the event thread */ 360 dbg("Signal event_semaphore"); 361 up(&event_semaphore); 362 dbg("exited cpci_hp_intr"); 363 return IRQ_HANDLED; 364 } 365 366 /* 367 * According to PICMG 2.1 R2.0, section 6.3.2, upon 368 * initialization, the system driver shall clear the 369 * INS bits of the cold-inserted devices. 370 */ 371 static int 372 init_slots(int clear_ins) 373 { 374 struct slot *slot; 375 struct pci_dev* dev; 376 377 dbg("%s - enter", __FUNCTION__); 378 down_read(&list_rwsem); 379 if (!slots) { 380 up_read(&list_rwsem); 381 return -1; 382 } 383 list_for_each_entry(slot, &slot_list, slot_list) { 384 dbg("%s - looking at slot %s", 385 __FUNCTION__, slot->hotplug_slot->name); 386 if (clear_ins && cpci_check_and_clear_ins(slot)) 387 dbg("%s - cleared INS for slot %s", 388 __FUNCTION__, slot->hotplug_slot->name); 389 dev = pci_get_slot(slot->bus, PCI_DEVFN(slot->number, 0)); 390 if (dev) { 391 if (update_adapter_status(slot->hotplug_slot, 1)) 392 warn("failure to update adapter file"); 393 if (update_latch_status(slot->hotplug_slot, 1)) 394 warn("failure to update latch file"); 395 slot->dev = dev; 396 } 397 } 398 up_read(&list_rwsem); 399 dbg("%s - exit", __FUNCTION__); 400 return 0; 401 } 402 403 static int 404 check_slots(void) 405 { 406 struct slot *slot; 407 int extracted; 408 int inserted; 409 u16 hs_csr; 410 411 down_read(&list_rwsem); 412 if (!slots) { 413 up_read(&list_rwsem); 414 err("no slots registered, shutting down"); 415 return -1; 416 } 417 extracted = inserted = 0; 418 list_for_each_entry(slot, &slot_list, slot_list) { 419 dbg("%s - looking at slot %s", 420 __FUNCTION__, slot->hotplug_slot->name); 421 if (cpci_check_and_clear_ins(slot)) { 422 /* 423 * Some broken hardware (e.g. PLX 9054AB) asserts 424 * ENUM# twice... 425 */ 426 if (slot->dev) { 427 warn("slot %s already inserted", 428 slot->hotplug_slot->name); 429 inserted++; 430 continue; 431 } 432 433 /* Process insertion */ 434 dbg("%s - slot %s inserted", 435 __FUNCTION__, slot->hotplug_slot->name); 436 437 /* GSM, debug */ 438 hs_csr = cpci_get_hs_csr(slot); 439 dbg("%s - slot %s HS_CSR (1) = %04x", 440 __FUNCTION__, slot->hotplug_slot->name, hs_csr); 441 442 /* Configure device */ 443 dbg("%s - configuring slot %s", 444 __FUNCTION__, slot->hotplug_slot->name); 445 if (cpci_configure_slot(slot)) { 446 err("%s - could not configure slot %s", 447 __FUNCTION__, slot->hotplug_slot->name); 448 continue; 449 } 450 dbg("%s - finished configuring slot %s", 451 __FUNCTION__, slot->hotplug_slot->name); 452 453 /* GSM, debug */ 454 hs_csr = cpci_get_hs_csr(slot); 455 dbg("%s - slot %s HS_CSR (2) = %04x", 456 __FUNCTION__, slot->hotplug_slot->name, hs_csr); 457 458 if (update_latch_status(slot->hotplug_slot, 1)) 459 warn("failure to update latch file"); 460 461 if (update_adapter_status(slot->hotplug_slot, 1)) 462 warn("failure to update adapter file"); 463 464 cpci_led_off(slot); 465 466 /* GSM, debug */ 467 hs_csr = cpci_get_hs_csr(slot); 468 dbg("%s - slot %s HS_CSR (3) = %04x", 469 __FUNCTION__, slot->hotplug_slot->name, hs_csr); 470 471 inserted++; 472 } else if (cpci_check_ext(slot)) { 473 /* Process extraction request */ 474 dbg("%s - slot %s extracted", 475 __FUNCTION__, slot->hotplug_slot->name); 476 477 /* GSM, debug */ 478 hs_csr = cpci_get_hs_csr(slot); 479 dbg("%s - slot %s HS_CSR = %04x", 480 __FUNCTION__, slot->hotplug_slot->name, hs_csr); 481 482 if (!slot->extracting) { 483 if (update_latch_status(slot->hotplug_slot, 0)) { 484 warn("failure to update latch file"); 485 } 486 slot->extracting = 1; 487 atomic_inc(&extracting); 488 } 489 extracted++; 490 } else if (slot->extracting) { 491 hs_csr = cpci_get_hs_csr(slot); 492 if (hs_csr == 0xffff) { 493 /* 494 * Hmmm, we're likely hosed at this point, should we 495 * bother trying to tell the driver or not? 496 */ 497 err("card in slot %s was improperly removed", 498 slot->hotplug_slot->name); 499 if (update_adapter_status(slot->hotplug_slot, 0)) 500 warn("failure to update adapter file"); 501 slot->extracting = 0; 502 atomic_dec(&extracting); 503 } 504 } 505 } 506 up_read(&list_rwsem); 507 dbg("inserted=%d, extracted=%d, extracting=%d", 508 inserted, extracted, atomic_read(&extracting)); 509 if (inserted || extracted) 510 return extracted; 511 else if (!atomic_read(&extracting)) { 512 err("cannot find ENUM# source, shutting down"); 513 return -1; 514 } 515 return 0; 516 } 517 518 /* This is the interrupt mode worker thread body */ 519 static int 520 event_thread(void *data) 521 { 522 int rc; 523 524 lock_kernel(); 525 daemonize("cpci_hp_eventd"); 526 unlock_kernel(); 527 528 dbg("%s - event thread started", __FUNCTION__); 529 while (1) { 530 dbg("event thread sleeping"); 531 down_interruptible(&event_semaphore); 532 dbg("event thread woken, thread_finished = %d", 533 thread_finished); 534 if (thread_finished || signal_pending(current)) 535 break; 536 do { 537 rc = check_slots(); 538 if (rc > 0) { 539 /* Give userspace a chance to handle extraction */ 540 msleep(500); 541 } else if (rc < 0) { 542 dbg("%s - error checking slots", __FUNCTION__); 543 thread_finished = 1; 544 break; 545 } 546 } while (atomic_read(&extracting) && !thread_finished); 547 if (thread_finished) 548 break; 549 550 /* Re-enable ENUM# interrupt */ 551 dbg("%s - re-enabling irq", __FUNCTION__); 552 controller->ops->enable_irq(); 553 } 554 dbg("%s - event thread signals exit", __FUNCTION__); 555 up(&thread_exit); 556 return 0; 557 } 558 559 /* This is the polling mode worker thread body */ 560 static int 561 poll_thread(void *data) 562 { 563 int rc; 564 565 lock_kernel(); 566 daemonize("cpci_hp_polld"); 567 unlock_kernel(); 568 569 while (1) { 570 if (thread_finished || signal_pending(current)) 571 break; 572 if (controller->ops->query_enum()) { 573 do { 574 rc = check_slots(); 575 if (rc > 0) { 576 /* Give userspace a chance to handle extraction */ 577 msleep(500); 578 } else if (rc < 0) { 579 dbg("%s - error checking slots", __FUNCTION__); 580 thread_finished = 1; 581 break; 582 } 583 } while (atomic_read(&extracting) && !thread_finished); 584 } 585 msleep(100); 586 } 587 dbg("poll thread signals exit"); 588 up(&thread_exit); 589 return 0; 590 } 591 592 static int 593 cpci_start_thread(void) 594 { 595 int pid; 596 597 /* initialize our semaphores */ 598 init_MUTEX_LOCKED(&event_semaphore); 599 init_MUTEX_LOCKED(&thread_exit); 600 thread_finished = 0; 601 602 if (controller->irq) 603 pid = kernel_thread(event_thread, NULL, 0); 604 else 605 pid = kernel_thread(poll_thread, NULL, 0); 606 if (pid < 0) { 607 err("Can't start up our thread"); 608 return -1; 609 } 610 dbg("Our thread pid = %d", pid); 611 return 0; 612 } 613 614 static void 615 cpci_stop_thread(void) 616 { 617 thread_finished = 1; 618 dbg("thread finish command given"); 619 if (controller->irq) 620 up(&event_semaphore); 621 dbg("wait for thread to exit"); 622 down(&thread_exit); 623 } 624 625 int 626 cpci_hp_register_controller(struct cpci_hp_controller *new_controller) 627 { 628 int status = 0; 629 630 if (controller) 631 return -1; 632 if (!(new_controller && new_controller->ops)) 633 return -EINVAL; 634 if (new_controller->irq) { 635 if (!(new_controller->ops->enable_irq && 636 new_controller->ops->disable_irq)) 637 status = -EINVAL; 638 if (request_irq(new_controller->irq, 639 cpci_hp_intr, 640 new_controller->irq_flags, 641 MY_NAME, 642 new_controller->dev_id)) { 643 err("Can't get irq %d for the hotplug cPCI controller", 644 new_controller->irq); 645 status = -ENODEV; 646 } 647 dbg("%s - acquired controller irq %d", 648 __FUNCTION__, new_controller->irq); 649 } 650 if (!status) 651 controller = new_controller; 652 return status; 653 } 654 655 static void 656 cleanup_slots(void) 657 { 658 struct slot *slot; 659 struct slot *tmp; 660 661 /* 662 * Unregister all of our slots with the pci_hotplug subsystem, 663 * and free up all memory that we had allocated. 664 */ 665 down_write(&list_rwsem); 666 if (!slots) 667 goto cleanup_null; 668 list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) { 669 list_del(&slot->slot_list); 670 pci_hp_deregister(slot->hotplug_slot); 671 } 672 cleanup_null: 673 up_write(&list_rwsem); 674 return; 675 } 676 677 int 678 cpci_hp_unregister_controller(struct cpci_hp_controller *old_controller) 679 { 680 int status = 0; 681 682 if (controller) { 683 if (!thread_finished) 684 cpci_stop_thread(); 685 if (controller->irq) 686 free_irq(controller->irq, controller->dev_id); 687 controller = NULL; 688 cleanup_slots(); 689 } else 690 status = -ENODEV; 691 return status; 692 } 693 694 int 695 cpci_hp_start(void) 696 { 697 static int first = 1; 698 int status; 699 700 dbg("%s - enter", __FUNCTION__); 701 if (!controller) 702 return -ENODEV; 703 704 down_read(&list_rwsem); 705 if (list_empty(&slot_list)) { 706 up_read(&list_rwsem); 707 return -ENODEV; 708 } 709 up_read(&list_rwsem); 710 711 status = init_slots(first); 712 if (first) 713 first = 0; 714 if (status) 715 return status; 716 717 status = cpci_start_thread(); 718 if (status) 719 return status; 720 dbg("%s - thread started", __FUNCTION__); 721 722 if (controller->irq) { 723 /* Start enum interrupt processing */ 724 dbg("%s - enabling irq", __FUNCTION__); 725 controller->ops->enable_irq(); 726 } 727 dbg("%s - exit", __FUNCTION__); 728 return 0; 729 } 730 731 int 732 cpci_hp_stop(void) 733 { 734 if (!controller) 735 return -ENODEV; 736 if (controller->irq) { 737 /* Stop enum interrupt processing */ 738 dbg("%s - disabling irq", __FUNCTION__); 739 controller->ops->disable_irq(); 740 } 741 cpci_stop_thread(); 742 return 0; 743 } 744 745 int __init 746 cpci_hotplug_init(int debug) 747 { 748 cpci_debug = debug; 749 return 0; 750 } 751 752 void __exit 753 cpci_hotplug_exit(void) 754 { 755 /* 756 * Clean everything up. 757 */ 758 cpci_hp_stop(); 759 cpci_hp_unregister_controller(controller); 760 } 761 762 EXPORT_SYMBOL_GPL(cpci_hp_register_controller); 763 EXPORT_SYMBOL_GPL(cpci_hp_unregister_controller); 764 EXPORT_SYMBOL_GPL(cpci_hp_register_bus); 765 EXPORT_SYMBOL_GPL(cpci_hp_unregister_bus); 766 EXPORT_SYMBOL_GPL(cpci_hp_start); 767 EXPORT_SYMBOL_GPL(cpci_hp_stop); 768