drivers/pci/hotplug/pciehp_ctrl.c

   1 /*
   2  * PCI Express Hot Plug Controller Driver
   3  *
   4  * Copyright (C) 1995,2001 Compaq Computer Corporation
   5  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
   6  * Copyright (C) 2001 IBM Corp.
   7  * Copyright (C) 2003-2004 Intel Corporation
   8  *
   9  * All rights reserved.
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or (at
  14  * your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful, but
  17  * WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  19  * NON INFRINGEMENT.  See the GNU General Public License for more
  20  * details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  25  *
  26  * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
  27  *
  28  */
  29
  30 #include <linux/module.h>
  31 #include <linux/kernel.h>
  32 #include <linux/types.h>
  33 #include <linux/slab.h>
  34 #include <linux/pci.h>
  35 #include "../pci.h"
  36 #include "pciehp.h"
  37
  38 static void interrupt_event_handler(struct work_struct *work);
  39
  40 static int queue_interrupt_event(struct slot *p_slot, u32 event_type)
  41 {
  42         struct event_info *info;
  43
  44         info = kmalloc(sizeof(*info), GFP_ATOMIC);
  45         if (!info)
  46                 return -ENOMEM;
  47
  48         info->event_type = event_type;
  49         info->p_slot = p_slot;
  50         INIT_WORK(&info->work, interrupt_event_handler);
  51
  52         queue_work(p_slot->wq, &info->work);
  53
  54         return 0;
  55 }
  56
  57 u8 pciehp_handle_attention_button(struct slot *p_slot)
  58 {
  59         u32 event_type;
  60         struct controller *ctrl = p_slot->ctrl;
  61
  62         /*
  63          *  Button pressed - See if need to TAKE ACTION!!!
  64          */
  65         ctrl_info(ctrl, "Button pressed on Slot(%s)\n", slot_name(p_slot));
  66         event_type = INT_BUTTON_PRESS;
  67
  68         queue_interrupt_event(p_slot, event_type);
  69
  70         return 0;
  71 }
  72
  73 u8 pciehp_handle_switch_change(struct slot *p_slot)
  74 {
  75         u8 getstatus;
  76         u32 event_type;
  77         struct controller *ctrl = p_slot->ctrl;
  78
  79         pciehp_get_latch_status(p_slot, &getstatus);
  80         if (getstatus) {
  81                 /*
  82                  * Switch opened
  83                  */
  84                 ctrl_info(ctrl, "Latch open on Slot(%s)\n", slot_name(p_slot));
  85                 event_type = INT_SWITCH_OPEN;
  86         } else {
  87                 /*
  88                  *  Switch closed
  89                  */
  90                 ctrl_info(ctrl, "Latch close on Slot(%s)\n", slot_name(p_slot));
  91                 event_type = INT_SWITCH_CLOSE;
  92         }
  93
  94         queue_interrupt_event(p_slot, event_type);
  95
  96         return 1;
  97 }
  98
  99 u8 pciehp_handle_presence_change(struct slot *p_slot)
 100 {
 101         u32 event_type;
 102         u8 presence_save;
 103         struct controller *ctrl = p_slot->ctrl;
 104
 105         /* Switch is open, assume a presence change
 106          * Save the presence state
 107          */
 108         pciehp_get_adapter_status(p_slot, &presence_save);
 109         if (presence_save) {
 110                 /*
 111                  * Card Present
 112                  */
 113                 ctrl_info(ctrl, "Card present on Slot(%s)\n", slot_name(p_slot));
 114                 event_type = INT_PRESENCE_ON;
 115         } else {
 116                 /*
 117                  * Not Present
 118                  */
 119                 ctrl_info(ctrl, "Card not present on Slot(%s)\n",
 120                           slot_name(p_slot));
 121                 event_type = INT_PRESENCE_OFF;
 122         }
 123
 124         queue_interrupt_event(p_slot, event_type);
 125
 126         return 1;
 127 }
 128
 129 u8 pciehp_handle_power_fault(struct slot *p_slot)
 130 {
 131         u32 event_type;
 132         struct controller *ctrl = p_slot->ctrl;
 133
 134         ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
 135         event_type = INT_POWER_FAULT;
 136         ctrl_info(ctrl, "Power fault bit %x set\n", 0);
 137         queue_interrupt_event(p_slot, event_type);
 138
 139         return 1;
 140 }
 141
 142 void pciehp_handle_linkstate_change(struct slot *p_slot)
 143 {
 144         u32 event_type;
 145         struct controller *ctrl = p_slot->ctrl;
 146
 147         if (pciehp_check_link_active(ctrl)) {
 148                 ctrl_info(ctrl, "slot(%s): Link Up event\n",
 149                           slot_name(p_slot));
 150                 event_type = INT_LINK_UP;
 151         } else {
 152                 ctrl_info(ctrl, "slot(%s): Link Down event\n",
 153                           slot_name(p_slot));
 154                 event_type = INT_LINK_DOWN;
 155         }
 156
 157         queue_interrupt_event(p_slot, event_type);
 158 }
 159
 160 /* The following routines constitute the bulk of the
 161    hotplug controller logic
 162  */
 163
 164 static void set_slot_off(struct controller *ctrl, struct slot *pslot)
 165 {
 166         /* turn off slot, turn on Amber LED, turn off Green LED if supported*/
 167         if (POWER_CTRL(ctrl)) {
 168                 pciehp_power_off_slot(pslot);
 169
 170                 /*
 171                  * After turning power off, we must wait for at least 1 second
 172                  * before taking any action that relies on power having been
 173                  * removed from the slot/adapter.
 174                  */
 175                 msleep(1000);
 176         }
 177
 178         pciehp_green_led_off(pslot);
 179         pciehp_set_attention_status(pslot, 1);
 180 }
 181
 182 /**
 183  * board_added - Called after a board has been added to the system.
 184  * @p_slot: &slot where board is added
 185  *
 186  * Turns power on for the board.
 187  * Configures board.
 188  */
 189 static int board_added(struct slot *p_slot)
 190 {
 191         int retval = 0;
 192         struct controller *ctrl = p_slot->ctrl;
 193         struct pci_bus *parent = ctrl->pcie->port->subordinate;
 194
 195         if (POWER_CTRL(ctrl)) {
 196                 /* Power on slot */
 197                 retval = pciehp_power_on_slot(p_slot);
 198                 if (retval)
 199                         return retval;
 200         }
 201
 202         pciehp_green_led_blink(p_slot);
 203
 204         /* Check link training status */
 205         retval = pciehp_check_link_status(ctrl);
 206         if (retval) {
 207                 ctrl_err(ctrl, "Failed to check link status\n");
 208                 goto err_exit;
 209         }
 210
 211         /* Check for a power fault */
 212         if (ctrl->power_fault_detected || pciehp_query_power_fault(p_slot)) {
 213                 ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
 214                 retval = -EIO;
 215                 goto err_exit;
 216         }
 217
 218         retval = pciehp_configure_device(p_slot);
 219         if (retval) {
 220                 ctrl_err(ctrl, "Cannot add device at %04x:%02x:00\n",
 221                          pci_domain_nr(parent), parent->number);
 222                 if (retval != -EEXIST)
 223                         goto err_exit;
 224         }
 225
 226         pciehp_green_led_on(p_slot);
 227         return 0;
 228
 229 err_exit:
 230         set_slot_off(ctrl, p_slot);
 231         return retval;
 232 }
 233
 234 /**
 235  * remove_board - Turns off slot and LEDs
 236  * @p_slot: slot where board is being removed
 237  */
 238 static int remove_board(struct slot *p_slot)
 239 {
 240         int retval;
 241         struct controller *ctrl = p_slot->ctrl;
 242
 243         retval = pciehp_unconfigure_device(p_slot);
 244         if (retval)
 245                 return retval;
 246
 247         if (POWER_CTRL(ctrl)) {
 248                 pciehp_power_off_slot(p_slot);
 249
 250                 /*
 251                  * After turning power off, we must wait for at least 1 second
 252                  * before taking any action that relies on power having been
 253                  * removed from the slot/adapter.
 254                  */
 255                 msleep(1000);
 256         }
 257
 258         /* turn off Green LED */
 259         pciehp_green_led_off(p_slot);
 260         return 0;
 261 }
 262
 263 struct power_work_info {
 264         struct slot *p_slot;
 265         struct work_struct work;
 266         unsigned int req;
 267 #define DISABLE_REQ 0
 268 #define ENABLE_REQ  1
 269 };
 270
 271 /**
 272  * pciehp_power_thread - handle pushbutton events
 273  * @work: &struct work_struct describing work to be done
 274  *
 275  * Scheduled procedure to handle blocking stuff for the pushbuttons.
 276  * Handles all pending events and exits.
 277  */
 278 static void pciehp_power_thread(struct work_struct *work)
 279 {
 280         struct power_work_info *info =
 281                 container_of(work, struct power_work_info, work);
 282         struct slot *p_slot = info->p_slot;
 283         int ret;
 284
 285         switch (info->req) {
 286         case DISABLE_REQ:
 287                 mutex_lock(&p_slot->hotplug_lock);
 288                 pciehp_disable_slot(p_slot);
 289                 mutex_unlock(&p_slot->hotplug_lock);
 290                 mutex_lock(&p_slot->lock);
 291                 p_slot->state = STATIC_STATE;
 292                 mutex_unlock(&p_slot->lock);
 293                 break;
 294         case ENABLE_REQ:
 295                 mutex_lock(&p_slot->hotplug_lock);
 296                 ret = pciehp_enable_slot(p_slot);
 297                 mutex_unlock(&p_slot->hotplug_lock);
 298                 if (ret)
 299                         pciehp_green_led_off(p_slot);
 300                 mutex_lock(&p_slot->lock);
 301                 p_slot->state = STATIC_STATE;
 302                 mutex_unlock(&p_slot->lock);
 303                 break;
 304         default:
 305                 break;
 306         }
 307
 308         kfree(info);
 309 }
 310
 311 void pciehp_queue_pushbutton_work(struct work_struct *work)
 312 {
 313         struct slot *p_slot = container_of(work, struct slot, work.work);
 314         struct power_work_info *info;
 315
 316         info = kmalloc(sizeof(*info), GFP_KERNEL);
 317         if (!info) {
 318                 ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
 319                          __func__);
 320                 return;
 321         }
 322         info->p_slot = p_slot;
 323         INIT_WORK(&info->work, pciehp_power_thread);
 324
 325         mutex_lock(&p_slot->lock);
 326         switch (p_slot->state) {
 327         case BLINKINGOFF_STATE:
 328                 p_slot->state = POWEROFF_STATE;
 329                 info->req = DISABLE_REQ;
 330                 break;
 331         case BLINKINGON_STATE:
 332                 p_slot->state = POWERON_STATE;
 333                 info->req = ENABLE_REQ;
 334                 break;
 335         default:
 336                 kfree(info);
 337                 goto out;
 338         }
 339         queue_work(p_slot->wq, &info->work);
 340  out:
 341         mutex_unlock(&p_slot->lock);
 342 }
 343
 344 /*
 345  * Note: This function must be called with slot->lock held
 346  */
 347 static void handle_button_press_event(struct slot *p_slot)
 348 {
 349         struct controller *ctrl = p_slot->ctrl;
 350         u8 getstatus;
 351
 352         switch (p_slot->state) {
 353         case STATIC_STATE:
 354                 pciehp_get_power_status(p_slot, &getstatus);
 355                 if (getstatus) {
 356                         p_slot->state = BLINKINGOFF_STATE;
 357                         ctrl_info(ctrl, "PCI slot #%s - powering off due to button press\n",
 358                                   slot_name(p_slot));
 359                 } else {
 360                         p_slot->state = BLINKINGON_STATE;
 361                         ctrl_info(ctrl, "PCI slot #%s - powering on due to button press\n",
 362                                   slot_name(p_slot));
 363                 }
 364                 /* blink green LED and turn off amber */
 365                 pciehp_green_led_blink(p_slot);
 366                 pciehp_set_attention_status(p_slot, 0);
 367                 queue_delayed_work(p_slot->wq, &p_slot->work, 5*HZ);
 368                 break;
 369         case BLINKINGOFF_STATE:
 370         case BLINKINGON_STATE:
 371                 /*
 372                  * Cancel if we are still blinking; this means that we
 373                  * press the attention again before the 5 sec. limit
 374                  * expires to cancel hot-add or hot-remove
 375                  */
 376                 ctrl_info(ctrl, "Button cancel on Slot(%s)\n", slot_name(p_slot));
 377                 cancel_delayed_work(&p_slot->work);
 378                 if (p_slot->state == BLINKINGOFF_STATE)
 379                         pciehp_green_led_on(p_slot);
 380                 else
 381                         pciehp_green_led_off(p_slot);
 382                 pciehp_set_attention_status(p_slot, 0);
 383                 ctrl_info(ctrl, "PCI slot #%s - action canceled due to button press\n",
 384                           slot_name(p_slot));
 385                 p_slot->state = STATIC_STATE;
 386                 break;
 387         case POWEROFF_STATE:
 388         case POWERON_STATE:
 389                 /*
 390                  * Ignore if the slot is on power-on or power-off state;
 391                  * this means that the previous attention button action
 392                  * to hot-add or hot-remove is undergoing
 393                  */
 394                 ctrl_info(ctrl, "Button ignore on Slot(%s)\n", slot_name(p_slot));
 395                 break;
 396         default:
 397                 ctrl_warn(ctrl, "ignoring invalid state %#x\n", p_slot->state);
 398                 break;
 399         }
 400 }
 401
 402 /*
 403  * Note: This function must be called with slot->lock held
 404  */
 405 static void handle_surprise_event(struct slot *p_slot)
 406 {
 407         u8 getstatus;
 408         struct power_work_info *info;
 409
 410         info = kmalloc(sizeof(*info), GFP_KERNEL);
 411         if (!info) {
 412                 ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
 413                          __func__);
 414                 return;
 415         }
 416         info->p_slot = p_slot;
 417         INIT_WORK(&info->work, pciehp_power_thread);
 418
 419         pciehp_get_adapter_status(p_slot, &getstatus);
 420         if (!getstatus) {
 421                 p_slot->state = POWEROFF_STATE;
 422                 info->req = DISABLE_REQ;
 423         } else {
 424                 p_slot->state = POWERON_STATE;
 425                 info->req = ENABLE_REQ;
 426         }
 427
 428         queue_work(p_slot->wq, &info->work);
 429 }
 430
 431 /*
 432  * Note: This function must be called with slot->lock held
 433  */
 434 static void handle_link_event(struct slot *p_slot, u32 event)
 435 {
 436         struct controller *ctrl = p_slot->ctrl;
 437         struct power_work_info *info;
 438
 439         info = kmalloc(sizeof(*info), GFP_KERNEL);
 440         if (!info) {
 441                 ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
 442                          __func__);
 443                 return;
 444         }
 445         info->p_slot = p_slot;
 446         info->req = event == INT_LINK_UP ? ENABLE_REQ : DISABLE_REQ;
 447         INIT_WORK(&info->work, pciehp_power_thread);
 448
 449         switch (p_slot->state) {
 450         case BLINKINGON_STATE:
 451         case BLINKINGOFF_STATE:
 452                 cancel_delayed_work(&p_slot->work);
 453                 /* Fall through */
 454         case STATIC_STATE:
 455                 p_slot->state = event == INT_LINK_UP ?
 456                     POWERON_STATE : POWEROFF_STATE;
 457                 queue_work(p_slot->wq, &info->work);
 458                 break;
 459         case POWERON_STATE:
 460                 if (event == INT_LINK_UP) {
 461                         ctrl_info(ctrl,
 462                                   "Link Up event ignored on slot(%s): already powering on\n",
 463                                   slot_name(p_slot));
 464                         kfree(info);
 465                 } else {
 466                         ctrl_info(ctrl,
 467                                   "Link Down event queued on slot(%s): currently getting powered on\n",
 468                                   slot_name(p_slot));
 469                         p_slot->state = POWEROFF_STATE;
 470                         queue_work(p_slot->wq, &info->work);
 471                 }
 472                 break;
 473         case POWEROFF_STATE:
 474                 if (event == INT_LINK_UP) {
 475                         ctrl_info(ctrl,
 476                                   "Link Up event queued on slot(%s): currently getting powered off\n",
 477                                   slot_name(p_slot));
 478                         p_slot->state = POWERON_STATE;
 479                         queue_work(p_slot->wq, &info->work);
 480                 } else {
 481                         ctrl_info(ctrl,
 482                                   "Link Down event ignored on slot(%s): already powering off\n",
 483                                   slot_name(p_slot));
 484                         kfree(info);
 485                 }
 486                 break;
 487         default:
 488                 ctrl_err(ctrl, "ignoring invalid state %#x on slot(%s)\n",
 489                          p_slot->state, slot_name(p_slot));
 490                 kfree(info);
 491                 break;
 492         }
 493 }
 494
 495 static void interrupt_event_handler(struct work_struct *work)
 496 {
 497         struct event_info *info = container_of(work, struct event_info, work);
 498         struct slot *p_slot = info->p_slot;
 499         struct controller *ctrl = p_slot->ctrl;
 500
 501         mutex_lock(&p_slot->lock);
 502         switch (info->event_type) {
 503         case INT_BUTTON_PRESS:
 504                 handle_button_press_event(p_slot);
 505                 break;
 506         case INT_POWER_FAULT:
 507                 if (!POWER_CTRL(ctrl))
 508                         break;
 509                 pciehp_set_attention_status(p_slot, 1);
 510                 pciehp_green_led_off(p_slot);
 511                 break;
 512         case INT_PRESENCE_ON:
 513                 handle_surprise_event(p_slot);
 514                 break;
 515         case INT_PRESENCE_OFF:
 516                 /*
 517                  * Regardless of surprise capability, we need to
 518                  * definitely remove a card that has been pulled out!
 519                  */
 520                 handle_surprise_event(p_slot);
 521                 break;
 522         case INT_LINK_UP:
 523         case INT_LINK_DOWN:
 524                 handle_link_event(p_slot, info->event_type);
 525                 break;
 526         default:
 527                 break;
 528         }
 529         mutex_unlock(&p_slot->lock);
 530
 531         kfree(info);
 532 }
 533
 534 /*
 535  * Note: This function must be called with slot->hotplug_lock held
 536  */
 537 int pciehp_enable_slot(struct slot *p_slot)
 538 {
 539         u8 getstatus = 0;
 540         int rc;
 541         struct controller *ctrl = p_slot->ctrl;
 542
 543         pciehp_get_adapter_status(p_slot, &getstatus);
 544         if (!getstatus) {
 545                 ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
 546                 return -ENODEV;
 547         }
 548         if (MRL_SENS(p_slot->ctrl)) {
 549                 pciehp_get_latch_status(p_slot, &getstatus);
 550                 if (getstatus) {
 551                         ctrl_info(ctrl, "Latch open on slot(%s)\n",
 552                                   slot_name(p_slot));
 553                         return -ENODEV;
 554                 }
 555         }
 556
 557         if (POWER_CTRL(p_slot->ctrl)) {
 558                 pciehp_get_power_status(p_slot, &getstatus);
 559                 if (getstatus) {
 560                         ctrl_info(ctrl, "Already enabled on slot(%s)\n",
 561                                   slot_name(p_slot));
 562                         return -EINVAL;
 563                 }
 564         }
 565
 566         pciehp_get_latch_status(p_slot, &getstatus);
 567
 568         rc = board_added(p_slot);
 569         if (rc)
 570                 pciehp_get_latch_status(p_slot, &getstatus);
 571
 572         return rc;
 573 }
 574
 575 /*
 576  * Note: This function must be called with slot->hotplug_lock held
 577  */
 578 int pciehp_disable_slot(struct slot *p_slot)
 579 {
 580         u8 getstatus = 0;
 581         struct controller *ctrl = p_slot->ctrl;
 582
 583         if (!p_slot->ctrl)
 584                 return 1;
 585
 586         if (POWER_CTRL(p_slot->ctrl)) {
 587                 pciehp_get_power_status(p_slot, &getstatus);
 588                 if (!getstatus) {
 589                         ctrl_info(ctrl, "Already disabled on slot(%s)\n",
 590                                   slot_name(p_slot));
 591                         return -EINVAL;
 592                 }
 593         }
 594
 595         return remove_board(p_slot);
 596 }
 597
 598 int pciehp_sysfs_enable_slot(struct slot *p_slot)
 599 {
 600         int retval = -ENODEV;
 601         struct controller *ctrl = p_slot->ctrl;
 602
 603         mutex_lock(&p_slot->lock);
 604         switch (p_slot->state) {
 605         case BLINKINGON_STATE:
 606                 cancel_delayed_work(&p_slot->work);
 607         case STATIC_STATE:
 608                 p_slot->state = POWERON_STATE;
 609                 mutex_unlock(&p_slot->lock);
 610                 mutex_lock(&p_slot->hotplug_lock);
 611                 retval = pciehp_enable_slot(p_slot);
 612                 mutex_unlock(&p_slot->hotplug_lock);
 613                 mutex_lock(&p_slot->lock);
 614                 p_slot->state = STATIC_STATE;
 615                 break;
 616         case POWERON_STATE:
 617                 ctrl_info(ctrl, "Slot %s is already in powering on state\n",
 618                           slot_name(p_slot));
 619                 break;
 620         case BLINKINGOFF_STATE:
 621         case POWEROFF_STATE:
 622                 ctrl_info(ctrl, "Already enabled on slot %s\n",
 623                           slot_name(p_slot));
 624                 break;
 625         default:
 626                 ctrl_err(ctrl, "invalid state %#x on slot %s\n",
 627                          p_slot->state, slot_name(p_slot));
 628                 break;
 629         }
 630         mutex_unlock(&p_slot->lock);
 631
 632         return retval;
 633 }
 634
 635 int pciehp_sysfs_disable_slot(struct slot *p_slot)
 636 {
 637         int retval = -ENODEV;
 638         struct controller *ctrl = p_slot->ctrl;
 639
 640         mutex_lock(&p_slot->lock);
 641         switch (p_slot->state) {
 642         case BLINKINGOFF_STATE:
 643                 cancel_delayed_work(&p_slot->work);
 644         case STATIC_STATE:
 645                 p_slot->state = POWEROFF_STATE;
 646                 mutex_unlock(&p_slot->lock);
 647                 retval = pciehp_disable_slot(p_slot);
 648                 mutex_lock(&p_slot->lock);
 649                 p_slot->state = STATIC_STATE;
 650                 break;
 651         case POWEROFF_STATE:
 652                 ctrl_info(ctrl, "Slot %s is already in powering off state\n",
 653                           slot_name(p_slot));
 654                 break;
 655         case BLINKINGON_STATE:
 656         case POWERON_STATE:
 657                 ctrl_info(ctrl, "Already disabled on slot %s\n",
 658                           slot_name(p_slot));
 659                 break;
 660         default:
 661                 ctrl_err(ctrl, "invalid state %#x on slot %s\n",
 662                          p_slot->state, slot_name(p_slot));
 663                 break;
 664         }
 665         mutex_unlock(&p_slot->lock);
 666
 667         return retval;
 668 }