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/config.h> 29 #include <linux/module.h> 30 #include <linux/kernel.h> 31 #include <linux/slab.h> 32 #include <linux/pci.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 "pci_hotplug.h" 39 #include "cpci_hotplug.h" 40 41 #define DRIVER_AUTHOR "Scott Murray <scottm@somanetworks.com>" 42 #define DRIVER_DESC "CompactPCI Hot Plug Core" 43 44 #define MY_NAME "cpci_hotplug" 45 46 #define dbg(format, arg...) \ 47 do { \ 48 if (cpci_debug) \ 49 printk (KERN_DEBUG "%s: " format "\n", \ 50 MY_NAME , ## arg); \ 51 } while (0) 52 #define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME , ## arg) 53 #define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME , ## arg) 54 #define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME , ## arg) 55 56 /* local variables */ 57 static DECLARE_RWSEM(list_rwsem); 58 static LIST_HEAD(slot_list); 59 static int slots; 60 static atomic_t extracting; 61 int cpci_debug; 62 static struct cpci_hp_controller *controller; 63 static struct semaphore event_semaphore; /* mutex for process loop (up if something to process) */ 64 static struct semaphore thread_exit; /* guard ensure thread has exited before calling it quits */ 65 static int thread_finished = 1; 66 67 static int enable_slot(struct hotplug_slot *slot); 68 static int disable_slot(struct hotplug_slot *slot); 69 static int set_attention_status(struct hotplug_slot *slot, u8 value); 70 static int get_power_status(struct hotplug_slot *slot, u8 * value); 71 static int get_attention_status(struct hotplug_slot *slot, u8 * value); 72 static int get_adapter_status(struct hotplug_slot *slot, u8 * value); 73 static int get_latch_status(struct hotplug_slot *slot, u8 * value); 74 75 static struct hotplug_slot_ops cpci_hotplug_slot_ops = { 76 .owner = THIS_MODULE, 77 .enable_slot = enable_slot, 78 .disable_slot = disable_slot, 79 .set_attention_status = set_attention_status, 80 .get_power_status = get_power_status, 81 .get_attention_status = get_attention_status, 82 .get_adapter_status = get_adapter_status, 83 .get_latch_status = get_latch_status, 84 }; 85 86 static int 87 update_latch_status(struct hotplug_slot *hotplug_slot, u8 value) 88 { 89 struct hotplug_slot_info info; 90 91 memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info)); 92 info.latch_status = value; 93 return pci_hp_change_slot_info(hotplug_slot, &info); 94 } 95 96 static int 97 update_adapter_status(struct hotplug_slot *hotplug_slot, u8 value) 98 { 99 struct hotplug_slot_info info; 100 101 memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info)); 102 info.adapter_status = value; 103 return pci_hp_change_slot_info(hotplug_slot, &info); 104 } 105 106 static int 107 enable_slot(struct hotplug_slot *hotplug_slot) 108 { 109 struct slot *slot = hotplug_slot->private; 110 int retval = 0; 111 112 dbg("%s - physical_slot = %s", __FUNCTION__, hotplug_slot->name); 113 114 if (controller->ops->set_power) 115 retval = controller->ops->set_power(slot, 1); 116 return retval; 117 } 118 119 static int 120 disable_slot(struct hotplug_slot *hotplug_slot) 121 { 122 struct slot *slot = hotplug_slot->private; 123 int retval = 0; 124 125 dbg("%s - physical_slot = %s", __FUNCTION__, hotplug_slot->name); 126 127 down_write(&list_rwsem); 128 129 /* Unconfigure device */ 130 dbg("%s - unconfiguring slot %s", 131 __FUNCTION__, slot->hotplug_slot->name); 132 if ((retval = cpci_unconfigure_slot(slot))) { 133 err("%s - could not unconfigure slot %s", 134 __FUNCTION__, slot->hotplug_slot->name); 135 goto disable_error; 136 } 137 dbg("%s - finished unconfiguring slot %s", 138 __FUNCTION__, slot->hotplug_slot->name); 139 140 /* Clear EXT (by setting it) */ 141 if (cpci_clear_ext(slot)) { 142 err("%s - could not clear EXT for slot %s", 143 __FUNCTION__, slot->hotplug_slot->name); 144 retval = -ENODEV; 145 goto disable_error; 146 } 147 cpci_led_on(slot); 148 149 if (controller->ops->set_power) 150 if ((retval = controller->ops->set_power(slot, 0))) 151 goto disable_error; 152 153 if (update_adapter_status(slot->hotplug_slot, 0)) 154 warn("failure to update adapter file"); 155 156 if (slot->extracting) { 157 slot->extracting = 0; 158 atomic_dec(&extracting); 159 } 160 disable_error: 161 up_write(&list_rwsem); 162 return retval; 163 } 164 165 static u8 166 cpci_get_power_status(struct slot *slot) 167 { 168 u8 power = 1; 169 170 if (controller->ops->get_power) 171 power = controller->ops->get_power(slot); 172 return power; 173 } 174 175 static int 176 get_power_status(struct hotplug_slot *hotplug_slot, u8 * value) 177 { 178 struct slot *slot = hotplug_slot->private; 179 180 *value = cpci_get_power_status(slot); 181 return 0; 182 } 183 184 static int 185 get_attention_status(struct hotplug_slot *hotplug_slot, u8 * value) 186 { 187 struct slot *slot = hotplug_slot->private; 188 189 *value = cpci_get_attention_status(slot); 190 return 0; 191 } 192 193 static int 194 set_attention_status(struct hotplug_slot *hotplug_slot, u8 status) 195 { 196 return cpci_set_attention_status(hotplug_slot->private, status); 197 } 198 199 static int 200 get_adapter_status(struct hotplug_slot *hotplug_slot, u8 * value) 201 { 202 *value = hotplug_slot->info->adapter_status; 203 return 0; 204 } 205 206 static int 207 get_latch_status(struct hotplug_slot *hotplug_slot, u8 * value) 208 { 209 *value = hotplug_slot->info->latch_status; 210 return 0; 211 } 212 213 static void release_slot(struct hotplug_slot *hotplug_slot) 214 { 215 struct slot *slot = hotplug_slot->private; 216 217 kfree(slot->hotplug_slot->info); 218 kfree(slot->hotplug_slot->name); 219 kfree(slot->hotplug_slot); 220 if (slot->dev) 221 pci_dev_put(slot->dev); 222 kfree(slot); 223 } 224 225 #define SLOT_NAME_SIZE 6 226 static void 227 make_slot_name(struct slot *slot) 228 { 229 snprintf(slot->hotplug_slot->name, 230 SLOT_NAME_SIZE, "%02x:%02x", slot->bus->number, slot->number); 231 } 232 233 int 234 cpci_hp_register_bus(struct pci_bus *bus, u8 first, u8 last) 235 { 236 struct slot *slot; 237 struct hotplug_slot *hotplug_slot; 238 struct hotplug_slot_info *info; 239 char *name; 240 int status = -ENOMEM; 241 int i; 242 243 if (!(controller && bus)) 244 return -ENODEV; 245 246 /* 247 * Create a structure for each slot, and register that slot 248 * with the pci_hotplug subsystem. 249 */ 250 for (i = first; i <= last; ++i) { 251 slot = kmalloc(sizeof (struct slot), GFP_KERNEL); 252 if (!slot) 253 goto error; 254 memset(slot, 0, sizeof (struct slot)); 255 256 hotplug_slot = 257 kmalloc(sizeof (struct hotplug_slot), GFP_KERNEL); 258 if (!hotplug_slot) 259 goto error_slot; 260 memset(hotplug_slot, 0, sizeof (struct hotplug_slot)); 261 slot->hotplug_slot = hotplug_slot; 262 263 info = kmalloc(sizeof (struct hotplug_slot_info), GFP_KERNEL); 264 if (!info) 265 goto error_hpslot; 266 memset(info, 0, sizeof (struct hotplug_slot_info)); 267 hotplug_slot->info = info; 268 269 name = kmalloc(SLOT_NAME_SIZE, GFP_KERNEL); 270 if (!name) 271 goto error_info; 272 hotplug_slot->name = name; 273 274 slot->bus = bus; 275 slot->number = i; 276 slot->devfn = PCI_DEVFN(i, 0); 277 278 hotplug_slot->private = slot; 279 hotplug_slot->release = &release_slot; 280 make_slot_name(slot); 281 hotplug_slot->ops = &cpci_hotplug_slot_ops; 282 283 /* 284 * Initialize the slot info structure with some known 285 * good values. 286 */ 287 dbg("initializing slot %s", slot->hotplug_slot->name); 288 info->power_status = cpci_get_power_status(slot); 289 info->attention_status = cpci_get_attention_status(slot); 290 291 dbg("registering slot %s", slot->hotplug_slot->name); 292 status = pci_hp_register(slot->hotplug_slot); 293 if (status) { 294 err("pci_hp_register failed with error %d", status); 295 goto error_name; 296 } 297 298 /* Add slot to our internal list */ 299 down_write(&list_rwsem); 300 list_add(&slot->slot_list, &slot_list); 301 slots++; 302 up_write(&list_rwsem); 303 } 304 return 0; 305 error_name: 306 kfree(name); 307 error_info: 308 kfree(info); 309 error_hpslot: 310 kfree(hotplug_slot); 311 error_slot: 312 kfree(slot); 313 error: 314 return status; 315 } 316 317 int 318 cpci_hp_unregister_bus(struct pci_bus *bus) 319 { 320 struct slot *slot; 321 struct slot *tmp; 322 int status = 0; 323 324 down_write(&list_rwsem); 325 if (!slots) { 326 up_write(&list_rwsem); 327 return -1; 328 } 329 list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) { 330 if (slot->bus == bus) { 331 list_del(&slot->slot_list); 332 slots--; 333 334 dbg("deregistering slot %s", slot->hotplug_slot->name); 335 status = pci_hp_deregister(slot->hotplug_slot); 336 if (status) { 337 err("pci_hp_deregister failed with error %d", 338 status); 339 break; 340 } 341 } 342 } 343 up_write(&list_rwsem); 344 return status; 345 } 346 347 /* This is the interrupt mode interrupt handler */ 348 static irqreturn_t 349 cpci_hp_intr(int irq, void *data, struct pt_regs *regs) 350 { 351 dbg("entered cpci_hp_intr"); 352 353 /* Check to see if it was our interrupt */ 354 if ((controller->irq_flags & SA_SHIRQ) && 355 !controller->ops->check_irq(controller->dev_id)) { 356 dbg("exited cpci_hp_intr, not our interrupt"); 357 return IRQ_NONE; 358 } 359 360 /* Disable ENUM interrupt */ 361 controller->ops->disable_irq(); 362 363 /* Trigger processing by the event thread */ 364 dbg("Signal event_semaphore"); 365 up(&event_semaphore); 366 dbg("exited cpci_hp_intr"); 367 return IRQ_HANDLED; 368 } 369 370 /* 371 * According to PICMG 2.1 R2.0, section 6.3.2, upon 372 * initialization, the system driver shall clear the 373 * INS bits of the cold-inserted devices. 374 */ 375 static int 376 init_slots(int clear_ins) 377 { 378 struct slot *slot; 379 struct pci_dev* dev; 380 381 dbg("%s - enter", __FUNCTION__); 382 down_read(&list_rwsem); 383 if (!slots) { 384 up_read(&list_rwsem); 385 return -1; 386 } 387 list_for_each_entry(slot, &slot_list, slot_list) { 388 dbg("%s - looking at slot %s", 389 __FUNCTION__, slot->hotplug_slot->name); 390 if (clear_ins && cpci_check_and_clear_ins(slot)) 391 dbg("%s - cleared INS for slot %s", 392 __FUNCTION__, slot->hotplug_slot->name); 393 dev = pci_get_slot(slot->bus, PCI_DEVFN(slot->number, 0)); 394 if (dev) { 395 if (update_adapter_status(slot->hotplug_slot, 1)) 396 warn("failure to update adapter file"); 397 if (update_latch_status(slot->hotplug_slot, 1)) 398 warn("failure to update latch file"); 399 slot->dev = dev; 400 } 401 } 402 up_read(&list_rwsem); 403 dbg("%s - exit", __FUNCTION__); 404 return 0; 405 } 406 407 static int 408 check_slots(void) 409 { 410 struct slot *slot; 411 int extracted; 412 int inserted; 413 u16 hs_csr; 414 415 down_read(&list_rwsem); 416 if (!slots) { 417 up_read(&list_rwsem); 418 err("no slots registered, shutting down"); 419 return -1; 420 } 421 extracted = inserted = 0; 422 list_for_each_entry(slot, &slot_list, slot_list) { 423 dbg("%s - looking at slot %s", 424 __FUNCTION__, slot->hotplug_slot->name); 425 if (cpci_check_and_clear_ins(slot)) { 426 /* 427 * Some broken hardware (e.g. PLX 9054AB) asserts 428 * ENUM# twice... 429 */ 430 if (slot->dev) { 431 warn("slot %s already inserted", 432 slot->hotplug_slot->name); 433 inserted++; 434 continue; 435 } 436 437 /* Process insertion */ 438 dbg("%s - slot %s inserted", 439 __FUNCTION__, slot->hotplug_slot->name); 440 441 /* GSM, debug */ 442 hs_csr = cpci_get_hs_csr(slot); 443 dbg("%s - slot %s HS_CSR (1) = %04x", 444 __FUNCTION__, slot->hotplug_slot->name, hs_csr); 445 446 /* Configure device */ 447 dbg("%s - configuring slot %s", 448 __FUNCTION__, slot->hotplug_slot->name); 449 if (cpci_configure_slot(slot)) { 450 err("%s - could not configure slot %s", 451 __FUNCTION__, slot->hotplug_slot->name); 452 continue; 453 } 454 dbg("%s - finished configuring slot %s", 455 __FUNCTION__, slot->hotplug_slot->name); 456 457 /* GSM, debug */ 458 hs_csr = cpci_get_hs_csr(slot); 459 dbg("%s - slot %s HS_CSR (2) = %04x", 460 __FUNCTION__, slot->hotplug_slot->name, hs_csr); 461 462 if (update_latch_status(slot->hotplug_slot, 1)) 463 warn("failure to update latch file"); 464 465 if (update_adapter_status(slot->hotplug_slot, 1)) 466 warn("failure to update adapter file"); 467 468 cpci_led_off(slot); 469 470 /* GSM, debug */ 471 hs_csr = cpci_get_hs_csr(slot); 472 dbg("%s - slot %s HS_CSR (3) = %04x", 473 __FUNCTION__, slot->hotplug_slot->name, hs_csr); 474 475 inserted++; 476 } else if (cpci_check_ext(slot)) { 477 /* Process extraction request */ 478 dbg("%s - slot %s extracted", 479 __FUNCTION__, slot->hotplug_slot->name); 480 481 /* GSM, debug */ 482 hs_csr = cpci_get_hs_csr(slot); 483 dbg("%s - slot %s HS_CSR = %04x", 484 __FUNCTION__, slot->hotplug_slot->name, hs_csr); 485 486 if (!slot->extracting) { 487 if (update_latch_status(slot->hotplug_slot, 0)) { 488 warn("failure to update latch file"); 489 } 490 slot->extracting = 1; 491 atomic_inc(&extracting); 492 } 493 extracted++; 494 } else if (slot->extracting) { 495 hs_csr = cpci_get_hs_csr(slot); 496 if (hs_csr == 0xffff) { 497 /* 498 * Hmmm, we're likely hosed at this point, should we 499 * bother trying to tell the driver or not? 500 */ 501 err("card in slot %s was improperly removed", 502 slot->hotplug_slot->name); 503 if (update_adapter_status(slot->hotplug_slot, 0)) 504 warn("failure to update adapter file"); 505 slot->extracting = 0; 506 atomic_dec(&extracting); 507 } 508 } 509 } 510 up_read(&list_rwsem); 511 dbg("inserted=%d, extracted=%d, extracting=%d", 512 inserted, extracted, atomic_read(&extracting)); 513 if (inserted || extracted) 514 return extracted; 515 else if (!atomic_read(&extracting)) { 516 err("cannot find ENUM# source, shutting down"); 517 return -1; 518 } 519 return 0; 520 } 521 522 /* This is the interrupt mode worker thread body */ 523 static int 524 event_thread(void *data) 525 { 526 int rc; 527 528 lock_kernel(); 529 daemonize("cpci_hp_eventd"); 530 unlock_kernel(); 531 532 dbg("%s - event thread started", __FUNCTION__); 533 while (1) { 534 dbg("event thread sleeping"); 535 down_interruptible(&event_semaphore); 536 dbg("event thread woken, thread_finished = %d", 537 thread_finished); 538 if (thread_finished || signal_pending(current)) 539 break; 540 do { 541 rc = check_slots(); 542 if (rc > 0) { 543 /* Give userspace a chance to handle extraction */ 544 msleep(500); 545 } else if (rc < 0) { 546 dbg("%s - error checking slots", __FUNCTION__); 547 thread_finished = 1; 548 break; 549 } 550 } while (atomic_read(&extracting) && !thread_finished); 551 if (thread_finished) 552 break; 553 554 /* Re-enable ENUM# interrupt */ 555 dbg("%s - re-enabling irq", __FUNCTION__); 556 controller->ops->enable_irq(); 557 } 558 dbg("%s - event thread signals exit", __FUNCTION__); 559 up(&thread_exit); 560 return 0; 561 } 562 563 /* This is the polling mode worker thread body */ 564 static int 565 poll_thread(void *data) 566 { 567 int rc; 568 569 lock_kernel(); 570 daemonize("cpci_hp_polld"); 571 unlock_kernel(); 572 573 while (1) { 574 if (thread_finished || signal_pending(current)) 575 break; 576 if (controller->ops->query_enum()) { 577 do { 578 rc = check_slots(); 579 if (rc > 0) { 580 /* Give userspace a chance to handle extraction */ 581 msleep(500); 582 } else if (rc < 0) { 583 dbg("%s - error checking slots", __FUNCTION__); 584 thread_finished = 1; 585 break; 586 } 587 } while (atomic_read(&extracting) && !thread_finished); 588 } 589 msleep(100); 590 } 591 dbg("poll thread signals exit"); 592 up(&thread_exit); 593 return 0; 594 } 595 596 static int 597 cpci_start_thread(void) 598 { 599 int pid; 600 601 /* initialize our semaphores */ 602 init_MUTEX_LOCKED(&event_semaphore); 603 init_MUTEX_LOCKED(&thread_exit); 604 thread_finished = 0; 605 606 if (controller->irq) 607 pid = kernel_thread(event_thread, NULL, 0); 608 else 609 pid = kernel_thread(poll_thread, NULL, 0); 610 if (pid < 0) { 611 err("Can't start up our thread"); 612 return -1; 613 } 614 dbg("Our thread pid = %d", pid); 615 return 0; 616 } 617 618 static void 619 cpci_stop_thread(void) 620 { 621 thread_finished = 1; 622 dbg("thread finish command given"); 623 if (controller->irq) 624 up(&event_semaphore); 625 dbg("wait for thread to exit"); 626 down(&thread_exit); 627 } 628 629 int 630 cpci_hp_register_controller(struct cpci_hp_controller *new_controller) 631 { 632 int status = 0; 633 634 if (controller) 635 return -1; 636 if (!(new_controller && new_controller->ops)) 637 return -EINVAL; 638 if (new_controller->irq) { 639 if (!(new_controller->ops->enable_irq && 640 new_controller->ops->disable_irq)) 641 status = -EINVAL; 642 if (request_irq(new_controller->irq, 643 cpci_hp_intr, 644 new_controller->irq_flags, 645 MY_NAME, 646 new_controller->dev_id)) { 647 err("Can't get irq %d for the hotplug cPCI controller", 648 new_controller->irq); 649 status = -ENODEV; 650 } 651 dbg("%s - acquired controller irq %d", 652 __FUNCTION__, new_controller->irq); 653 } 654 if (!status) 655 controller = new_controller; 656 return status; 657 } 658 659 static void 660 cleanup_slots(void) 661 { 662 struct slot *slot; 663 struct slot *tmp; 664 665 /* 666 * Unregister all of our slots with the pci_hotplug subsystem, 667 * and free up all memory that we had allocated. 668 */ 669 down_write(&list_rwsem); 670 if (!slots) 671 goto cleanup_null; 672 list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) { 673 list_del(&slot->slot_list); 674 pci_hp_deregister(slot->hotplug_slot); 675 } 676 cleanup_null: 677 up_write(&list_rwsem); 678 return; 679 } 680 681 int 682 cpci_hp_unregister_controller(struct cpci_hp_controller *old_controller) 683 { 684 int status = 0; 685 686 if (controller) { 687 if (!thread_finished) 688 cpci_stop_thread(); 689 if (controller->irq) 690 free_irq(controller->irq, controller->dev_id); 691 controller = NULL; 692 cleanup_slots(); 693 } else 694 status = -ENODEV; 695 return status; 696 } 697 698 int 699 cpci_hp_start(void) 700 { 701 static int first = 1; 702 int status; 703 704 dbg("%s - enter", __FUNCTION__); 705 if (!controller) 706 return -ENODEV; 707 708 down_read(&list_rwsem); 709 if (list_empty(&slot_list)) { 710 up_read(&list_rwsem); 711 return -ENODEV; 712 } 713 up_read(&list_rwsem); 714 715 status = init_slots(first); 716 if (first) 717 first = 0; 718 if (status) 719 return status; 720 721 status = cpci_start_thread(); 722 if (status) 723 return status; 724 dbg("%s - thread started", __FUNCTION__); 725 726 if (controller->irq) { 727 /* Start enum interrupt processing */ 728 dbg("%s - enabling irq", __FUNCTION__); 729 controller->ops->enable_irq(); 730 } 731 dbg("%s - exit", __FUNCTION__); 732 return 0; 733 } 734 735 int 736 cpci_hp_stop(void) 737 { 738 if (!controller) 739 return -ENODEV; 740 if (controller->irq) { 741 /* Stop enum interrupt processing */ 742 dbg("%s - disabling irq", __FUNCTION__); 743 controller->ops->disable_irq(); 744 } 745 cpci_stop_thread(); 746 return 0; 747 } 748 749 int __init 750 cpci_hotplug_init(int debug) 751 { 752 cpci_debug = debug; 753 return 0; 754 } 755 756 void __exit 757 cpci_hotplug_exit(void) 758 { 759 /* 760 * Clean everything up. 761 */ 762 cpci_hp_stop(); 763 cpci_hp_unregister_controller(controller); 764 } 765 766 EXPORT_SYMBOL_GPL(cpci_hp_register_controller); 767 EXPORT_SYMBOL_GPL(cpci_hp_unregister_controller); 768 EXPORT_SYMBOL_GPL(cpci_hp_register_bus); 769 EXPORT_SYMBOL_GPL(cpci_hp_unregister_bus); 770 EXPORT_SYMBOL_GPL(cpci_hp_start); 771 EXPORT_SYMBOL_GPL(cpci_hp_stop); 772