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         /* Attention Button Change */
  63         ctrl_dbg(ctrl, "Attention button interrupt received\n");
  64
  65         /*
  66          *  Button pressed - See if need to TAKE ACTION!!!
  67          */
  68         ctrl_info(ctrl, "Button pressed on Slot(%s)\n", slot_name(p_slot));
  69         event_type = INT_BUTTON_PRESS;
  70
  71         queue_interrupt_event(p_slot, event_type);
  72
  73         return 0;
  74 }
  75
  76 u8 pciehp_handle_switch_change(struct slot *p_slot)
  77 {
  78         u8 getstatus;
  79         u32 event_type;
  80         struct controller *ctrl = p_slot->ctrl;
  81
  82         /* Switch Change */
  83         ctrl_dbg(ctrl, "Switch interrupt received\n");
  84
  85         pciehp_get_latch_status(p_slot, &getstatus);
  86         if (getstatus) {
  87                 /*
  88                  * Switch opened
  89                  */
  90                 ctrl_info(ctrl, "Latch open on Slot(%s)\n", slot_name(p_slot));
  91                 event_type = INT_SWITCH_OPEN;
  92         } else {
  93                 /*
  94                  *  Switch closed
  95                  */
  96                 ctrl_info(ctrl, "Latch close on Slot(%s)\n", slot_name(p_slot));
  97                 event_type = INT_SWITCH_CLOSE;
  98         }
  99
 100         queue_interrupt_event(p_slot, event_type);
 101
 102         return 1;
 103 }
 104
 105 u8 pciehp_handle_presence_change(struct slot *p_slot)
 106 {
 107         u32 event_type;
 108         u8 presence_save;
 109         struct controller *ctrl = p_slot->ctrl;
 110
 111         /* Presence Change */
 112         ctrl_dbg(ctrl, "Presence/Notify input change\n");
 113
 114         /* Switch is open, assume a presence change
 115          * Save the presence state
 116          */
 117         pciehp_get_adapter_status(p_slot, &presence_save);
 118         if (presence_save) {
 119                 /*
 120                  * Card Present
 121                  */
 122                 ctrl_info(ctrl, "Card present on Slot(%s)\n", slot_name(p_slot));
 123                 event_type = INT_PRESENCE_ON;
 124         } else {
 125                 /*
 126                  * Not Present
 127                  */
 128                 ctrl_info(ctrl, "Card not present on Slot(%s)\n",
 129                           slot_name(p_slot));
 130                 event_type = INT_PRESENCE_OFF;
 131         }
 132
 133         queue_interrupt_event(p_slot, event_type);
 134
 135         return 1;
 136 }
 137
 138 u8 pciehp_handle_power_fault(struct slot *p_slot)
 139 {
 140         u32 event_type;
 141         struct controller *ctrl = p_slot->ctrl;
 142
 143         /* power fault */
 144         ctrl_dbg(ctrl, "Power fault interrupt received\n");
 145         ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
 146         event_type = INT_POWER_FAULT;
 147         ctrl_info(ctrl, "Power fault bit %x set\n", 0);
 148         queue_interrupt_event(p_slot, event_type);
 149
 150         return 1;
 151 }
 152
 153 /* The following routines constitute the bulk of the
 154    hotplug controller logic
 155  */
 156
 157 static void set_slot_off(struct controller *ctrl, struct slot * pslot)
 158 {
 159         /* turn off slot, turn on Amber LED, turn off Green LED if supported*/
 160         if (POWER_CTRL(ctrl)) {
 161                 pciehp_power_off_slot(pslot);
 162
 163                 /*
 164                  * After turning power off, we must wait for at least 1 second
 165                  * before taking any action that relies on power having been
 166                  * removed from the slot/adapter.
 167                  */
 168                 msleep(1000);
 169         }
 170
 171         pciehp_green_led_off(pslot);
 172         pciehp_set_attention_status(pslot, 1);
 173 }
 174
 175 /**
 176  * board_added - Called after a board has been added to the system.
 177  * @p_slot: &slot where board is added
 178  *
 179  * Turns power on for the board.
 180  * Configures board.
 181  */
 182 static int board_added(struct slot *p_slot)
 183 {
 184         int retval = 0;
 185         struct controller *ctrl = p_slot->ctrl;
 186         struct pci_bus *parent = ctrl->pcie->port->subordinate;
 187
 188         if (POWER_CTRL(ctrl)) {
 189                 /* Power on slot */
 190                 retval = pciehp_power_on_slot(p_slot);
 191                 if (retval)
 192                         return retval;
 193         }
 194
 195         pciehp_green_led_blink(p_slot);
 196
 197         /* Check link training status */
 198         retval = pciehp_check_link_status(ctrl);
 199         if (retval) {
 200                 ctrl_err(ctrl, "Failed to check link status\n");
 201                 goto err_exit;
 202         }
 203
 204         /* Check for a power fault */
 205         if (ctrl->power_fault_detected || pciehp_query_power_fault(p_slot)) {
 206                 ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
 207                 retval = -EIO;
 208                 goto err_exit;
 209         }
 210
 211         retval = pciehp_configure_device(p_slot);
 212         if (retval) {
 213                 ctrl_err(ctrl, "Cannot add device at %04x:%02x:00\n",
 214                          pci_domain_nr(parent), parent->number);
 215                 goto err_exit;
 216         }
 217
 218         pciehp_green_led_on(p_slot);
 219         return 0;
 220
 221 err_exit:
 222         set_slot_off(ctrl, p_slot);
 223         return retval;
 224 }
 225
 226 /**
 227  * remove_board - Turns off slot and LEDs
 228  * @p_slot: slot where board is being removed
 229  */
 230 static int remove_board(struct slot *p_slot)
 231 {
 232         int retval;
 233         struct controller *ctrl = p_slot->ctrl;
 234
 235         retval = pciehp_unconfigure_device(p_slot);
 236         if (retval)
 237                 return retval;
 238
 239         if (POWER_CTRL(ctrl)) {
 240                 pciehp_power_off_slot(p_slot);
 241
 242                 /*
 243                  * After turning power off, we must wait for at least 1 second
 244                  * before taking any action that relies on power having been
 245                  * removed from the slot/adapter.
 246                  */
 247                 msleep(1000);
 248         }
 249
 250         /* turn off Green LED */
 251         pciehp_green_led_off(p_slot);
 252         return 0;
 253 }
 254
 255 struct power_work_info {
 256         struct slot *p_slot;
 257         struct work_struct work;
 258 };
 259
 260 /**
 261  * pciehp_power_thread - handle pushbutton events
 262  * @work: &struct work_struct describing work to be done
 263  *
 264  * Scheduled procedure to handle blocking stuff for the pushbuttons.
 265  * Handles all pending events and exits.
 266  */
 267 static void pciehp_power_thread(struct work_struct *work)
 268 {
 269         struct power_work_info *info =
 270                 container_of(work, struct power_work_info, work);
 271         struct slot *p_slot = info->p_slot;
 272
 273         mutex_lock(&p_slot->lock);
 274         switch (p_slot->state) {
 275         case POWEROFF_STATE:
 276                 mutex_unlock(&p_slot->lock);
 277                 ctrl_dbg(p_slot->ctrl,
 278                          "Disabling domain:bus:device=%04x:%02x:00\n",
 279                          pci_domain_nr(p_slot->ctrl->pcie->port->subordinate),
 280                          p_slot->ctrl->pcie->port->subordinate->number);
 281                 pciehp_disable_slot(p_slot);
 282                 mutex_lock(&p_slot->lock);
 283                 p_slot->state = STATIC_STATE;
 284                 break;
 285         case POWERON_STATE:
 286                 mutex_unlock(&p_slot->lock);
 287                 if (pciehp_enable_slot(p_slot))
 288                         pciehp_green_led_off(p_slot);
 289                 mutex_lock(&p_slot->lock);
 290                 p_slot->state = STATIC_STATE;
 291                 break;
 292         default:
 293                 break;
 294         }
 295         mutex_unlock(&p_slot->lock);
 296
 297         kfree(info);
 298 }
 299
 300 void pciehp_queue_pushbutton_work(struct work_struct *work)
 301 {
 302         struct slot *p_slot = container_of(work, struct slot, work.work);
 303         struct power_work_info *info;
 304
 305         info = kmalloc(sizeof(*info), GFP_KERNEL);
 306         if (!info) {
 307                 ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
 308                          __func__);
 309                 return;
 310         }
 311         info->p_slot = p_slot;
 312         INIT_WORK(&info->work, pciehp_power_thread);
 313
 314         mutex_lock(&p_slot->lock);
 315         switch (p_slot->state) {
 316         case BLINKINGOFF_STATE:
 317                 p_slot->state = POWEROFF_STATE;
 318                 break;
 319         case BLINKINGON_STATE:
 320                 p_slot->state = POWERON_STATE;
 321                 break;
 322         default:
 323                 kfree(info);
 324                 goto out;
 325         }
 326         queue_work(p_slot->wq, &info->work);
 327  out:
 328         mutex_unlock(&p_slot->lock);
 329 }
 330
 331 /*
 332  * Note: This function must be called with slot->lock held
 333  */
 334 static void handle_button_press_event(struct slot *p_slot)
 335 {
 336         struct controller *ctrl = p_slot->ctrl;
 337         u8 getstatus;
 338
 339         switch (p_slot->state) {
 340         case STATIC_STATE:
 341                 pciehp_get_power_status(p_slot, &getstatus);
 342                 if (getstatus) {
 343                         p_slot->state = BLINKINGOFF_STATE;
 344                         ctrl_info(ctrl,
 345                                   "PCI slot #%s - powering off due to button "
 346                                   "press.\n", slot_name(p_slot));
 347                 } else {
 348                         p_slot->state = BLINKINGON_STATE;
 349                         ctrl_info(ctrl,
 350                                   "PCI slot #%s - powering on due to button "
 351                                   "press.\n", slot_name(p_slot));
 352                 }
 353                 /* blink green LED and turn off amber */
 354                 pciehp_green_led_blink(p_slot);
 355                 pciehp_set_attention_status(p_slot, 0);
 356                 queue_delayed_work(p_slot->wq, &p_slot->work, 5*HZ);
 357                 break;
 358         case BLINKINGOFF_STATE:
 359         case BLINKINGON_STATE:
 360                 /*
 361                  * Cancel if we are still blinking; this means that we
 362                  * press the attention again before the 5 sec. limit
 363                  * expires to cancel hot-add or hot-remove
 364                  */
 365                 ctrl_info(ctrl, "Button cancel on Slot(%s)\n", slot_name(p_slot));
 366                 cancel_delayed_work(&p_slot->work);
 367                 if (p_slot->state == BLINKINGOFF_STATE) {
 368                         pciehp_green_led_on(p_slot);
 369                 } else {
 370                         pciehp_green_led_off(p_slot);
 371                 }
 372                 pciehp_set_attention_status(p_slot, 0);
 373                 ctrl_info(ctrl, "PCI slot #%s - action canceled "
 374                           "due to button press\n", slot_name(p_slot));
 375                 p_slot->state = STATIC_STATE;
 376                 break;
 377         case POWEROFF_STATE:
 378         case POWERON_STATE:
 379                 /*
 380                  * Ignore if the slot is on power-on or power-off state;
 381                  * this means that the previous attention button action
 382                  * to hot-add or hot-remove is undergoing
 383                  */
 384                 ctrl_info(ctrl, "Button ignore on Slot(%s)\n", slot_name(p_slot));
 385                 break;
 386         default:
 387                 ctrl_warn(ctrl, "Not a valid state\n");
 388                 break;
 389         }
 390 }
 391
 392 /*
 393  * Note: This function must be called with slot->lock held
 394  */
 395 static void handle_surprise_event(struct slot *p_slot)
 396 {
 397         u8 getstatus;
 398         struct power_work_info *info;
 399
 400         info = kmalloc(sizeof(*info), GFP_KERNEL);
 401         if (!info) {
 402                 ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
 403                          __func__);
 404                 return;
 405         }
 406         info->p_slot = p_slot;
 407         INIT_WORK(&info->work, pciehp_power_thread);
 408
 409         pciehp_get_adapter_status(p_slot, &getstatus);
 410         if (!getstatus)
 411                 p_slot->state = POWEROFF_STATE;
 412         else
 413                 p_slot->state = POWERON_STATE;
 414
 415         queue_work(p_slot->wq, &info->work);
 416 }
 417
 418 static void interrupt_event_handler(struct work_struct *work)
 419 {
 420         struct event_info *info = container_of(work, struct event_info, work);
 421         struct slot *p_slot = info->p_slot;
 422         struct controller *ctrl = p_slot->ctrl;
 423
 424         mutex_lock(&p_slot->lock);
 425         switch (info->event_type) {
 426         case INT_BUTTON_PRESS:
 427                 handle_button_press_event(p_slot);
 428                 break;
 429         case INT_POWER_FAULT:
 430                 if (!POWER_CTRL(ctrl))
 431                         break;
 432                 pciehp_set_attention_status(p_slot, 1);
 433                 pciehp_green_led_off(p_slot);
 434                 break;
 435         case INT_PRESENCE_ON:
 436         case INT_PRESENCE_OFF:
 437                 if (!HP_SUPR_RM(ctrl))
 438                         break;
 439                 ctrl_dbg(ctrl, "Surprise Removal\n");
 440                 handle_surprise_event(p_slot);
 441                 break;
 442         default:
 443                 break;
 444         }
 445         mutex_unlock(&p_slot->lock);
 446
 447         kfree(info);
 448 }
 449
 450 int pciehp_enable_slot(struct slot *p_slot)
 451 {
 452         u8 getstatus = 0;
 453         int rc;
 454         struct controller *ctrl = p_slot->ctrl;
 455
 456         pciehp_get_adapter_status(p_slot, &getstatus);
 457         if (!getstatus) {
 458                 ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
 459                 return -ENODEV;
 460         }
 461         if (MRL_SENS(p_slot->ctrl)) {
 462                 pciehp_get_latch_status(p_slot, &getstatus);
 463                 if (getstatus) {
 464                         ctrl_info(ctrl, "Latch open on slot(%s)\n",
 465                                   slot_name(p_slot));
 466                         return -ENODEV;
 467                 }
 468         }
 469
 470         if (POWER_CTRL(p_slot->ctrl)) {
 471                 pciehp_get_power_status(p_slot, &getstatus);
 472                 if (getstatus) {
 473                         ctrl_info(ctrl, "Already enabled on slot(%s)\n",
 474                                   slot_name(p_slot));
 475                         return -EINVAL;
 476                 }
 477         }
 478
 479         pciehp_get_latch_status(p_slot, &getstatus);
 480
 481         rc = board_added(p_slot);
 482         if (rc) {
 483                 pciehp_get_latch_status(p_slot, &getstatus);
 484         }
 485         return rc;
 486 }
 487
 488
 489 int pciehp_disable_slot(struct slot *p_slot)
 490 {
 491         u8 getstatus = 0;
 492         struct controller *ctrl = p_slot->ctrl;
 493
 494         if (!p_slot->ctrl)
 495                 return 1;
 496
 497         if (!HP_SUPR_RM(p_slot->ctrl)) {
 498                 pciehp_get_adapter_status(p_slot, &getstatus);
 499                 if (!getstatus) {
 500                         ctrl_info(ctrl, "No adapter on slot(%s)\n",
 501                                   slot_name(p_slot));
 502                         return -ENODEV;
 503                 }
 504         }
 505
 506         if (MRL_SENS(p_slot->ctrl)) {
 507                 pciehp_get_latch_status(p_slot, &getstatus);
 508                 if (getstatus) {
 509                         ctrl_info(ctrl, "Latch open on slot(%s)\n",
 510                                   slot_name(p_slot));
 511                         return -ENODEV;
 512                 }
 513         }
 514
 515         if (POWER_CTRL(p_slot->ctrl)) {
 516                 pciehp_get_power_status(p_slot, &getstatus);
 517                 if (!getstatus) {
 518                         ctrl_info(ctrl, "Already disabled on slot(%s)\n",
 519                                   slot_name(p_slot));
 520                         return -EINVAL;
 521                 }
 522         }
 523
 524         return remove_board(p_slot);
 525 }
 526
 527 int pciehp_sysfs_enable_slot(struct slot *p_slot)
 528 {
 529         int retval = -ENODEV;
 530         struct controller *ctrl = p_slot->ctrl;
 531
 532         mutex_lock(&p_slot->lock);
 533         switch (p_slot->state) {
 534         case BLINKINGON_STATE:
 535                 cancel_delayed_work(&p_slot->work);
 536         case STATIC_STATE:
 537                 p_slot->state = POWERON_STATE;
 538                 mutex_unlock(&p_slot->lock);
 539                 retval = pciehp_enable_slot(p_slot);
 540                 mutex_lock(&p_slot->lock);
 541                 p_slot->state = STATIC_STATE;
 542                 break;
 543         case POWERON_STATE:
 544                 ctrl_info(ctrl, "Slot %s is already in powering on state\n",
 545                           slot_name(p_slot));
 546                 break;
 547         case BLINKINGOFF_STATE:
 548         case POWEROFF_STATE:
 549                 ctrl_info(ctrl, "Already enabled on slot %s\n",
 550                           slot_name(p_slot));
 551                 break;
 552         default:
 553                 ctrl_err(ctrl, "Not a valid state on slot %s\n",
 554                          slot_name(p_slot));
 555                 break;
 556         }
 557         mutex_unlock(&p_slot->lock);
 558
 559         return retval;
 560 }
 561
 562 int pciehp_sysfs_disable_slot(struct slot *p_slot)
 563 {
 564         int retval = -ENODEV;
 565         struct controller *ctrl = p_slot->ctrl;
 566
 567         mutex_lock(&p_slot->lock);
 568         switch (p_slot->state) {
 569         case BLINKINGOFF_STATE:
 570                 cancel_delayed_work(&p_slot->work);
 571         case STATIC_STATE:
 572                 p_slot->state = POWEROFF_STATE;
 573                 mutex_unlock(&p_slot->lock);
 574                 retval = pciehp_disable_slot(p_slot);
 575                 mutex_lock(&p_slot->lock);
 576                 p_slot->state = STATIC_STATE;
 577                 break;
 578         case POWEROFF_STATE:
 579                 ctrl_info(ctrl, "Slot %s is already in powering off state\n",
 580                           slot_name(p_slot));
 581                 break;
 582         case BLINKINGON_STATE:
 583         case POWERON_STATE:
 584                 ctrl_info(ctrl, "Already disabled on slot %s\n",
 585                           slot_name(p_slot));
 586                 break;
 587         default:
 588                 ctrl_err(ctrl, "Not a valid state on slot %s\n",
 589                          slot_name(p_slot));
 590                 break;
 591         }
 592         mutex_unlock(&p_slot->lock);
 593
 594         return retval;
 595 }