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 <linux/kthread.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 task_struct *cpci_thread; 64 static int thread_finished; 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 wake_up_process(cpci_thread); 361 return IRQ_HANDLED; 362 } 363 364 /* 365 * According to PICMG 2.1 R2.0, section 6.3.2, upon 366 * initialization, the system driver shall clear the 367 * INS bits of the cold-inserted devices. 368 */ 369 static int 370 init_slots(int clear_ins) 371 { 372 struct slot *slot; 373 struct pci_dev* dev; 374 375 dbg("%s - enter", __FUNCTION__); 376 down_read(&list_rwsem); 377 if (!slots) { 378 up_read(&list_rwsem); 379 return -1; 380 } 381 list_for_each_entry(slot, &slot_list, slot_list) { 382 dbg("%s - looking at slot %s", 383 __FUNCTION__, slot->hotplug_slot->name); 384 if (clear_ins && cpci_check_and_clear_ins(slot)) 385 dbg("%s - cleared INS for slot %s", 386 __FUNCTION__, slot->hotplug_slot->name); 387 dev = pci_get_slot(slot->bus, PCI_DEVFN(slot->number, 0)); 388 if (dev) { 389 if (update_adapter_status(slot->hotplug_slot, 1)) 390 warn("failure to update adapter file"); 391 if (update_latch_status(slot->hotplug_slot, 1)) 392 warn("failure to update latch file"); 393 slot->dev = dev; 394 } 395 } 396 up_read(&list_rwsem); 397 dbg("%s - exit", __FUNCTION__); 398 return 0; 399 } 400 401 static int 402 check_slots(void) 403 { 404 struct slot *slot; 405 int extracted; 406 int inserted; 407 u16 hs_csr; 408 409 down_read(&list_rwsem); 410 if (!slots) { 411 up_read(&list_rwsem); 412 err("no slots registered, shutting down"); 413 return -1; 414 } 415 extracted = inserted = 0; 416 list_for_each_entry(slot, &slot_list, slot_list) { 417 dbg("%s - looking at slot %s", 418 __FUNCTION__, slot->hotplug_slot->name); 419 if (cpci_check_and_clear_ins(slot)) { 420 /* 421 * Some broken hardware (e.g. PLX 9054AB) asserts 422 * ENUM# twice... 423 */ 424 if (slot->dev) { 425 warn("slot %s already inserted", 426 slot->hotplug_slot->name); 427 inserted++; 428 continue; 429 } 430 431 /* Process insertion */ 432 dbg("%s - slot %s inserted", 433 __FUNCTION__, slot->hotplug_slot->name); 434 435 /* GSM, debug */ 436 hs_csr = cpci_get_hs_csr(slot); 437 dbg("%s - slot %s HS_CSR (1) = %04x", 438 __FUNCTION__, slot->hotplug_slot->name, hs_csr); 439 440 /* Configure device */ 441 dbg("%s - configuring slot %s", 442 __FUNCTION__, slot->hotplug_slot->name); 443 if (cpci_configure_slot(slot)) { 444 err("%s - could not configure slot %s", 445 __FUNCTION__, slot->hotplug_slot->name); 446 continue; 447 } 448 dbg("%s - finished configuring slot %s", 449 __FUNCTION__, slot->hotplug_slot->name); 450 451 /* GSM, debug */ 452 hs_csr = cpci_get_hs_csr(slot); 453 dbg("%s - slot %s HS_CSR (2) = %04x", 454 __FUNCTION__, slot->hotplug_slot->name, hs_csr); 455 456 if (update_latch_status(slot->hotplug_slot, 1)) 457 warn("failure to update latch file"); 458 459 if (update_adapter_status(slot->hotplug_slot, 1)) 460 warn("failure to update adapter file"); 461 462 cpci_led_off(slot); 463 464 /* GSM, debug */ 465 hs_csr = cpci_get_hs_csr(slot); 466 dbg("%s - slot %s HS_CSR (3) = %04x", 467 __FUNCTION__, slot->hotplug_slot->name, hs_csr); 468 469 inserted++; 470 } else if (cpci_check_ext(slot)) { 471 /* Process extraction request */ 472 dbg("%s - slot %s extracted", 473 __FUNCTION__, slot->hotplug_slot->name); 474 475 /* GSM, debug */ 476 hs_csr = cpci_get_hs_csr(slot); 477 dbg("%s - slot %s HS_CSR = %04x", 478 __FUNCTION__, slot->hotplug_slot->name, hs_csr); 479 480 if (!slot->extracting) { 481 if (update_latch_status(slot->hotplug_slot, 0)) { 482 warn("failure to update latch file"); 483 } 484 slot->extracting = 1; 485 atomic_inc(&extracting); 486 } 487 extracted++; 488 } else if (slot->extracting) { 489 hs_csr = cpci_get_hs_csr(slot); 490 if (hs_csr == 0xffff) { 491 /* 492 * Hmmm, we're likely hosed at this point, should we 493 * bother trying to tell the driver or not? 494 */ 495 err("card in slot %s was improperly removed", 496 slot->hotplug_slot->name); 497 if (update_adapter_status(slot->hotplug_slot, 0)) 498 warn("failure to update adapter file"); 499 slot->extracting = 0; 500 atomic_dec(&extracting); 501 } 502 } 503 } 504 up_read(&list_rwsem); 505 dbg("inserted=%d, extracted=%d, extracting=%d", 506 inserted, extracted, atomic_read(&extracting)); 507 if (inserted || extracted) 508 return extracted; 509 else if (!atomic_read(&extracting)) { 510 err("cannot find ENUM# source, shutting down"); 511 return -1; 512 } 513 return 0; 514 } 515 516 /* This is the interrupt mode worker thread body */ 517 static int 518 event_thread(void *data) 519 { 520 int rc; 521 522 dbg("%s - event thread started", __FUNCTION__); 523 while (1) { 524 dbg("event thread sleeping"); 525 set_current_state(TASK_INTERRUPTIBLE); 526 schedule(); 527 if (kthread_should_stop()) 528 break; 529 do { 530 rc = check_slots(); 531 if (rc > 0) { 532 /* Give userspace a chance to handle extraction */ 533 msleep(500); 534 } else if (rc < 0) { 535 dbg("%s - error checking slots", __FUNCTION__); 536 thread_finished = 1; 537 goto out; 538 } 539 } while (atomic_read(&extracting) && !kthread_should_stop()); 540 if (kthread_should_stop()) 541 break; 542 543 /* Re-enable ENUM# interrupt */ 544 dbg("%s - re-enabling irq", __FUNCTION__); 545 controller->ops->enable_irq(); 546 } 547 out: 548 return 0; 549 } 550 551 /* This is the polling mode worker thread body */ 552 static int 553 poll_thread(void *data) 554 { 555 int rc; 556 557 while (1) { 558 if (kthread_should_stop() || signal_pending(current)) 559 break; 560 if (controller->ops->query_enum()) { 561 do { 562 rc = check_slots(); 563 if (rc > 0) { 564 /* Give userspace a chance to handle extraction */ 565 msleep(500); 566 } else if (rc < 0) { 567 dbg("%s - error checking slots", __FUNCTION__); 568 thread_finished = 1; 569 goto out; 570 } 571 } while (atomic_read(&extracting) && !kthread_should_stop()); 572 } 573 msleep(100); 574 } 575 out: 576 return 0; 577 } 578 579 static int 580 cpci_start_thread(void) 581 { 582 if (controller->irq) 583 cpci_thread = kthread_run(event_thread, NULL, "cpci_hp_eventd"); 584 else 585 cpci_thread = kthread_run(poll_thread, NULL, "cpci_hp_polld"); 586 if (IS_ERR(cpci_thread)) { 587 err("Can't start up our thread"); 588 return PTR_ERR(cpci_thread); 589 } 590 thread_finished = 0; 591 return 0; 592 } 593 594 static void 595 cpci_stop_thread(void) 596 { 597 kthread_stop(cpci_thread); 598 thread_finished = 1; 599 } 600 601 int 602 cpci_hp_register_controller(struct cpci_hp_controller *new_controller) 603 { 604 int status = 0; 605 606 if (controller) 607 return -1; 608 if (!(new_controller && new_controller->ops)) 609 return -EINVAL; 610 if (new_controller->irq) { 611 if (!(new_controller->ops->enable_irq && 612 new_controller->ops->disable_irq)) 613 status = -EINVAL; 614 if (request_irq(new_controller->irq, 615 cpci_hp_intr, 616 new_controller->irq_flags, 617 MY_NAME, 618 new_controller->dev_id)) { 619 err("Can't get irq %d for the hotplug cPCI controller", 620 new_controller->irq); 621 status = -ENODEV; 622 } 623 dbg("%s - acquired controller irq %d", 624 __FUNCTION__, new_controller->irq); 625 } 626 if (!status) 627 controller = new_controller; 628 return status; 629 } 630 631 static void 632 cleanup_slots(void) 633 { 634 struct slot *slot; 635 struct slot *tmp; 636 637 /* 638 * Unregister all of our slots with the pci_hotplug subsystem, 639 * and free up all memory that we had allocated. 640 */ 641 down_write(&list_rwsem); 642 if (!slots) 643 goto cleanup_null; 644 list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) { 645 list_del(&slot->slot_list); 646 pci_hp_deregister(slot->hotplug_slot); 647 } 648 cleanup_null: 649 up_write(&list_rwsem); 650 return; 651 } 652 653 int 654 cpci_hp_unregister_controller(struct cpci_hp_controller *old_controller) 655 { 656 int status = 0; 657 658 if (controller) { 659 if (!thread_finished) 660 cpci_stop_thread(); 661 if (controller->irq) 662 free_irq(controller->irq, controller->dev_id); 663 controller = NULL; 664 cleanup_slots(); 665 } else 666 status = -ENODEV; 667 return status; 668 } 669 670 int 671 cpci_hp_start(void) 672 { 673 static int first = 1; 674 int status; 675 676 dbg("%s - enter", __FUNCTION__); 677 if (!controller) 678 return -ENODEV; 679 680 down_read(&list_rwsem); 681 if (list_empty(&slot_list)) { 682 up_read(&list_rwsem); 683 return -ENODEV; 684 } 685 up_read(&list_rwsem); 686 687 status = init_slots(first); 688 if (first) 689 first = 0; 690 if (status) 691 return status; 692 693 status = cpci_start_thread(); 694 if (status) 695 return status; 696 dbg("%s - thread started", __FUNCTION__); 697 698 if (controller->irq) { 699 /* Start enum interrupt processing */ 700 dbg("%s - enabling irq", __FUNCTION__); 701 controller->ops->enable_irq(); 702 } 703 dbg("%s - exit", __FUNCTION__); 704 return 0; 705 } 706 707 int 708 cpci_hp_stop(void) 709 { 710 if (!controller) 711 return -ENODEV; 712 if (controller->irq) { 713 /* Stop enum interrupt processing */ 714 dbg("%s - disabling irq", __FUNCTION__); 715 controller->ops->disable_irq(); 716 } 717 cpci_stop_thread(); 718 return 0; 719 } 720 721 int __init 722 cpci_hotplug_init(int debug) 723 { 724 cpci_debug = debug; 725 return 0; 726 } 727 728 void __exit 729 cpci_hotplug_exit(void) 730 { 731 /* 732 * Clean everything up. 733 */ 734 cpci_hp_stop(); 735 cpci_hp_unregister_controller(controller); 736 } 737 738 EXPORT_SYMBOL_GPL(cpci_hp_register_controller); 739 EXPORT_SYMBOL_GPL(cpci_hp_unregister_controller); 740 EXPORT_SYMBOL_GPL(cpci_hp_register_bus); 741 EXPORT_SYMBOL_GPL(cpci_hp_unregister_bus); 742 EXPORT_SYMBOL_GPL(cpci_hp_start); 743 EXPORT_SYMBOL_GPL(cpci_hp_stop); 744