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