drivers/pci/hotplug/pciehp_hpc.c

   1 /*
   2  * PCI Express PCI Hot Plug 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/kernel.h>
  31 #include <linux/module.h>
  32 #include <linux/types.h>
  33 #include <linux/signal.h>
  34 #include <linux/jiffies.h>
  35 #include <linux/timer.h>
  36 #include <linux/pci.h>
  37 #include <linux/interrupt.h>
  38 #include <linux/time.h>
  39 #include <linux/slab.h>
  40
  41 #include "../pci.h"
  42 #include "pciehp.h"
  43
  44 static inline struct pci_dev *ctrl_dev(struct controller *ctrl)
  45 {
  46         return ctrl->pcie->port;
  47 }
  48
  49 static irqreturn_t pcie_isr(int irq, void *dev_id);
  50 static void start_int_poll_timer(struct controller *ctrl, int sec);
  51
  52 /* This is the interrupt polling timeout function. */
  53 static void int_poll_timeout(unsigned long data)
  54 {
  55         struct controller *ctrl = (struct controller *)data;
  56
  57         /* Poll for interrupt events.  regs == NULL => polling */
  58         pcie_isr(0, ctrl);
  59
  60         init_timer(&ctrl->poll_timer);
  61         if (!pciehp_poll_time)
  62                 pciehp_poll_time = 2; /* default polling interval is 2 sec */
  63
  64         start_int_poll_timer(ctrl, pciehp_poll_time);
  65 }
  66
  67 /* This function starts the interrupt polling timer. */
  68 static void start_int_poll_timer(struct controller *ctrl, int sec)
  69 {
  70         /* Clamp to sane value */
  71         if ((sec <= 0) || (sec > 60))
  72                 sec = 2;
  73
  74         ctrl->poll_timer.function = &int_poll_timeout;
  75         ctrl->poll_timer.data = (unsigned long)ctrl;
  76         ctrl->poll_timer.expires = jiffies + sec * HZ;
  77         add_timer(&ctrl->poll_timer);
  78 }
  79
  80 static inline int pciehp_request_irq(struct controller *ctrl)
  81 {
  82         int retval, irq = ctrl->pcie->irq;
  83
  84         /* Install interrupt polling timer. Start with 10 sec delay */
  85         if (pciehp_poll_mode) {
  86                 init_timer(&ctrl->poll_timer);
  87                 start_int_poll_timer(ctrl, 10);
  88                 return 0;
  89         }
  90
  91         /* Installs the interrupt handler */
  92         retval = request_irq(irq, pcie_isr, IRQF_SHARED, MY_NAME, ctrl);
  93         if (retval)
  94                 ctrl_err(ctrl, "Cannot get irq %d for the hotplug controller\n",
  95                          irq);
  96         return retval;
  97 }
  98
  99 static inline void pciehp_free_irq(struct controller *ctrl)
 100 {
 101         if (pciehp_poll_mode)
 102                 del_timer_sync(&ctrl->poll_timer);
 103         else
 104                 free_irq(ctrl->pcie->irq, ctrl);
 105 }
 106
 107 static int pcie_poll_cmd(struct controller *ctrl)
 108 {
 109         struct pci_dev *pdev = ctrl_dev(ctrl);
 110         u16 slot_status;
 111         int timeout = 1000;
 112
 113         pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
 114         if (slot_status & PCI_EXP_SLTSTA_CC) {
 115                 pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
 116                                            PCI_EXP_SLTSTA_CC);
 117                 return 1;
 118         }
 119         while (timeout > 0) {
 120                 msleep(10);
 121                 timeout -= 10;
 122                 pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
 123                 if (slot_status & PCI_EXP_SLTSTA_CC) {
 124                         pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
 125                                                    PCI_EXP_SLTSTA_CC);
 126                         return 1;
 127                 }
 128         }
 129         return 0;       /* timeout */
 130 }
 131
 132 static void pcie_wait_cmd(struct controller *ctrl, int poll)
 133 {
 134         unsigned int msecs = pciehp_poll_mode ? 2500 : 1000;
 135         unsigned long timeout = msecs_to_jiffies(msecs);
 136         int rc;
 137
 138         if (poll)
 139                 rc = pcie_poll_cmd(ctrl);
 140         else
 141                 rc = wait_event_timeout(ctrl->queue, !ctrl->cmd_busy, timeout);
 142         if (!rc)
 143                 ctrl_dbg(ctrl, "Command not completed in 1000 msec\n");
 144 }
 145
 146 /**
 147  * pcie_write_cmd - Issue controller command
 148  * @ctrl: controller to which the command is issued
 149  * @cmd:  command value written to slot control register
 150  * @mask: bitmask of slot control register to be modified
 151  */
 152 static void pcie_write_cmd(struct controller *ctrl, u16 cmd, u16 mask)
 153 {
 154         struct pci_dev *pdev = ctrl_dev(ctrl);
 155         u16 slot_status;
 156         u16 slot_ctrl;
 157
 158         mutex_lock(&ctrl->ctrl_lock);
 159
 160         pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
 161         if (slot_status & PCI_EXP_SLTSTA_CC) {
 162                 pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
 163                                            PCI_EXP_SLTSTA_CC);
 164                 if (!ctrl->no_cmd_complete) {
 165                         /*
 166                          * After 1 sec and CMD_COMPLETED still not set, just
 167                          * proceed forward to issue the next command according
 168                          * to spec. Just print out the error message.
 169                          */
 170                         ctrl_dbg(ctrl, "CMD_COMPLETED not clear after 1 sec\n");
 171                 } else if (!NO_CMD_CMPL(ctrl)) {
 172                         /*
 173                          * This controller seems to notify of command completed
 174                          * event even though it supports none of power
 175                          * controller, attention led, power led and EMI.
 176                          */
 177                         ctrl_dbg(ctrl, "Unexpected CMD_COMPLETED. Need to wait for command completed event\n");
 178                         ctrl->no_cmd_complete = 0;
 179                 } else {
 180                         ctrl_dbg(ctrl, "Unexpected CMD_COMPLETED. Maybe the controller is broken\n");
 181                 }
 182         }
 183
 184         pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
 185         slot_ctrl &= ~mask;
 186         slot_ctrl |= (cmd & mask);
 187         ctrl->cmd_busy = 1;
 188         smp_mb();
 189         pcie_capability_write_word(pdev, PCI_EXP_SLTCTL, slot_ctrl);
 190
 191         /*
 192          * Wait for command completion.
 193          */
 194         if (!ctrl->no_cmd_complete) {
 195                 int poll = 0;
 196                 /*
 197                  * if hotplug interrupt is not enabled or command
 198                  * completed interrupt is not enabled, we need to poll
 199                  * command completed event.
 200                  */
 201                 if (!(slot_ctrl & PCI_EXP_SLTCTL_HPIE) ||
 202                     !(slot_ctrl & PCI_EXP_SLTCTL_CCIE))
 203                         poll = 1;
 204                 pcie_wait_cmd(ctrl, poll);
 205         }
 206         mutex_unlock(&ctrl->ctrl_lock);
 207 }
 208
 209 bool pciehp_check_link_active(struct controller *ctrl)
 210 {
 211         struct pci_dev *pdev = ctrl_dev(ctrl);
 212         u16 lnk_status;
 213         bool ret;
 214
 215         pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
 216         ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA);
 217
 218         if (ret)
 219                 ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status);
 220
 221         return ret;
 222 }
 223
 224 static void __pcie_wait_link_active(struct controller *ctrl, bool active)
 225 {
 226         int timeout = 1000;
 227
 228         if (pciehp_check_link_active(ctrl) == active)
 229                 return;
 230         while (timeout > 0) {
 231                 msleep(10);
 232                 timeout -= 10;
 233                 if (pciehp_check_link_active(ctrl) == active)
 234                         return;
 235         }
 236         ctrl_dbg(ctrl, "Data Link Layer Link Active not %s in 1000 msec\n",
 237                         active ? "set" : "cleared");
 238 }
 239
 240 static void pcie_wait_link_active(struct controller *ctrl)
 241 {
 242         __pcie_wait_link_active(ctrl, true);
 243 }
 244
 245 static bool pci_bus_check_dev(struct pci_bus *bus, int devfn)
 246 {
 247         u32 l;
 248         int count = 0;
 249         int delay = 1000, step = 20;
 250         bool found = false;
 251
 252         do {
 253                 found = pci_bus_read_dev_vendor_id(bus, devfn, &l, 0);
 254                 count++;
 255
 256                 if (found)
 257                         break;
 258
 259                 msleep(step);
 260                 delay -= step;
 261         } while (delay > 0);
 262
 263         if (count > 1 && pciehp_debug)
 264                 printk(KERN_DEBUG "pci %04x:%02x:%02x.%d id reading try %d times with interval %d ms to get %08x\n",
 265                         pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
 266                         PCI_FUNC(devfn), count, step, l);
 267
 268         return found;
 269 }
 270
 271 int pciehp_check_link_status(struct controller *ctrl)
 272 {
 273         struct pci_dev *pdev = ctrl_dev(ctrl);
 274         bool found;
 275         u16 lnk_status;
 276
 277         /*
 278          * Data Link Layer Link Active Reporting must be capable for
 279          * hot-plug capable downstream port. But old controller might
 280          * not implement it. In this case, we wait for 1000 ms.
 281         */
 282         if (ctrl->link_active_reporting)
 283                 pcie_wait_link_active(ctrl);
 284         else
 285                 msleep(1000);
 286
 287         /* wait 100ms before read pci conf, and try in 1s */
 288         msleep(100);
 289         found = pci_bus_check_dev(ctrl->pcie->port->subordinate,
 290                                         PCI_DEVFN(0, 0));
 291
 292         pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
 293         ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status);
 294         if ((lnk_status & PCI_EXP_LNKSTA_LT) ||
 295             !(lnk_status & PCI_EXP_LNKSTA_NLW)) {
 296                 ctrl_err(ctrl, "Link Training Error occurs\n");
 297                 return -1;
 298         }
 299
 300         pcie_update_link_speed(ctrl->pcie->port->subordinate, lnk_status);
 301
 302         if (!found)
 303                 return -1;
 304
 305         return 0;
 306 }
 307
 308 static int __pciehp_link_set(struct controller *ctrl, bool enable)
 309 {
 310         struct pci_dev *pdev = ctrl_dev(ctrl);
 311         u16 lnk_ctrl;
 312
 313         pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &lnk_ctrl);
 314
 315         if (enable)
 316                 lnk_ctrl &= ~PCI_EXP_LNKCTL_LD;
 317         else
 318                 lnk_ctrl |= PCI_EXP_LNKCTL_LD;
 319
 320         pcie_capability_write_word(pdev, PCI_EXP_LNKCTL, lnk_ctrl);
 321         ctrl_dbg(ctrl, "%s: lnk_ctrl = %x\n", __func__, lnk_ctrl);
 322         return 0;
 323 }
 324
 325 static int pciehp_link_enable(struct controller *ctrl)
 326 {
 327         return __pciehp_link_set(ctrl, true);
 328 }
 329
 330 void pciehp_get_attention_status(struct slot *slot, u8 *status)
 331 {
 332         struct controller *ctrl = slot->ctrl;
 333         struct pci_dev *pdev = ctrl_dev(ctrl);
 334         u16 slot_ctrl;
 335
 336         pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
 337         ctrl_dbg(ctrl, "%s: SLOTCTRL %x, value read %x\n", __func__,
 338                  pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl);
 339
 340         switch (slot_ctrl & PCI_EXP_SLTCTL_AIC) {
 341         case PCI_EXP_SLTCTL_ATTN_IND_ON:
 342                 *status = 1;    /* On */
 343                 break;
 344         case PCI_EXP_SLTCTL_ATTN_IND_BLINK:
 345                 *status = 2;    /* Blink */
 346                 break;
 347         case PCI_EXP_SLTCTL_ATTN_IND_OFF:
 348                 *status = 0;    /* Off */
 349                 break;
 350         default:
 351                 *status = 0xFF;
 352                 break;
 353         }
 354 }
 355
 356 void pciehp_get_power_status(struct slot *slot, u8 *status)
 357 {
 358         struct controller *ctrl = slot->ctrl;
 359         struct pci_dev *pdev = ctrl_dev(ctrl);
 360         u16 slot_ctrl;
 361
 362         pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
 363         ctrl_dbg(ctrl, "%s: SLOTCTRL %x value read %x\n", __func__,
 364                  pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl);
 365
 366         switch (slot_ctrl & PCI_EXP_SLTCTL_PCC) {
 367         case PCI_EXP_SLTCTL_PWR_ON:
 368                 *status = 1;    /* On */
 369                 break;
 370         case PCI_EXP_SLTCTL_PWR_OFF:
 371                 *status = 0;    /* Off */
 372                 break;
 373         default:
 374                 *status = 0xFF;
 375                 break;
 376         }
 377 }
 378
 379 void pciehp_get_latch_status(struct slot *slot, u8 *status)
 380 {
 381         struct pci_dev *pdev = ctrl_dev(slot->ctrl);
 382         u16 slot_status;
 383
 384         pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
 385         *status = !!(slot_status & PCI_EXP_SLTSTA_MRLSS);
 386 }
 387
 388 void pciehp_get_adapter_status(struct slot *slot, u8 *status)
 389 {
 390         struct pci_dev *pdev = ctrl_dev(slot->ctrl);
 391         u16 slot_status;
 392
 393         pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
 394         *status = !!(slot_status & PCI_EXP_SLTSTA_PDS);
 395 }
 396
 397 int pciehp_query_power_fault(struct slot *slot)
 398 {
 399         struct pci_dev *pdev = ctrl_dev(slot->ctrl);
 400         u16 slot_status;
 401
 402         pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
 403         return !!(slot_status & PCI_EXP_SLTSTA_PFD);
 404 }
 405
 406 void pciehp_set_attention_status(struct slot *slot, u8 value)
 407 {
 408         struct controller *ctrl = slot->ctrl;
 409         u16 slot_cmd;
 410
 411         if (!ATTN_LED(ctrl))
 412                 return;
 413
 414         switch (value) {
 415         case 0:         /* turn off */
 416                 slot_cmd = PCI_EXP_SLTCTL_ATTN_IND_OFF;
 417                 break;
 418         case 1:         /* turn on */
 419                 slot_cmd = PCI_EXP_SLTCTL_ATTN_IND_ON;
 420                 break;
 421         case 2:         /* turn blink */
 422                 slot_cmd = PCI_EXP_SLTCTL_ATTN_IND_BLINK;
 423                 break;
 424         default:
 425                 return;
 426         }
 427         ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 428                  pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
 429         pcie_write_cmd(ctrl, slot_cmd, PCI_EXP_SLTCTL_AIC);
 430 }
 431
 432 void pciehp_green_led_on(struct slot *slot)
 433 {
 434         struct controller *ctrl = slot->ctrl;
 435
 436         if (!PWR_LED(ctrl))
 437                 return;
 438
 439         pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_IND_ON, PCI_EXP_SLTCTL_PIC);
 440         ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 441                  pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
 442                  PCI_EXP_SLTCTL_PWR_IND_ON);
 443 }
 444
 445 void pciehp_green_led_off(struct slot *slot)
 446 {
 447         struct controller *ctrl = slot->ctrl;
 448
 449         if (!PWR_LED(ctrl))
 450                 return;
 451
 452         pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF, PCI_EXP_SLTCTL_PIC);
 453         ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 454                  pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
 455                  PCI_EXP_SLTCTL_PWR_IND_OFF);
 456 }
 457
 458 void pciehp_green_led_blink(struct slot *slot)
 459 {
 460         struct controller *ctrl = slot->ctrl;
 461
 462         if (!PWR_LED(ctrl))
 463                 return;
 464
 465         pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_IND_BLINK, PCI_EXP_SLTCTL_PIC);
 466         ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 467                  pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
 468                  PCI_EXP_SLTCTL_PWR_IND_BLINK);
 469 }
 470
 471 int pciehp_power_on_slot(struct slot *slot)
 472 {
 473         struct controller *ctrl = slot->ctrl;
 474         struct pci_dev *pdev = ctrl_dev(ctrl);
 475         u16 slot_status;
 476         int retval;
 477
 478         /* Clear sticky power-fault bit from previous power failures */
 479         pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
 480         if (slot_status & PCI_EXP_SLTSTA_PFD)
 481                 pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
 482                                            PCI_EXP_SLTSTA_PFD);
 483         ctrl->power_fault_detected = 0;
 484
 485         pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_ON, PCI_EXP_SLTCTL_PCC);
 486         ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 487                  pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
 488                  PCI_EXP_SLTCTL_PWR_ON);
 489
 490         retval = pciehp_link_enable(ctrl);
 491         if (retval)
 492                 ctrl_err(ctrl, "%s: Can not enable the link!\n", __func__);
 493
 494         return retval;
 495 }
 496
 497 void pciehp_power_off_slot(struct slot *slot)
 498 {
 499         struct controller *ctrl = slot->ctrl;
 500
 501         pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_OFF, PCI_EXP_SLTCTL_PCC);
 502         ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 503                  pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
 504                  PCI_EXP_SLTCTL_PWR_OFF);
 505 }
 506
 507 static irqreturn_t pcie_isr(int irq, void *dev_id)
 508 {
 509         struct controller *ctrl = (struct controller *)dev_id;
 510         struct pci_dev *pdev = ctrl_dev(ctrl);
 511         struct slot *slot = ctrl->slot;
 512         u16 detected, intr_loc;
 513
 514         /*
 515          * In order to guarantee that all interrupt events are
 516          * serviced, we need to re-inspect Slot Status register after
 517          * clearing what is presumed to be the last pending interrupt.
 518          */
 519         intr_loc = 0;
 520         do {
 521                 pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &detected);
 522
 523                 detected &= (PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD |
 524                              PCI_EXP_SLTSTA_MRLSC | PCI_EXP_SLTSTA_PDC |
 525                              PCI_EXP_SLTSTA_CC | PCI_EXP_SLTSTA_DLLSC);
 526                 detected &= ~intr_loc;
 527                 intr_loc |= detected;
 528                 if (!intr_loc)
 529                         return IRQ_NONE;
 530                 if (detected)
 531                         pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
 532                                                    intr_loc);
 533         } while (detected);
 534
 535         ctrl_dbg(ctrl, "%s: intr_loc %x\n", __func__, intr_loc);
 536
 537         /* Check Command Complete Interrupt Pending */
 538         if (intr_loc & PCI_EXP_SLTSTA_CC) {
 539                 ctrl->cmd_busy = 0;
 540                 smp_mb();
 541                 wake_up(&ctrl->queue);
 542         }
 543
 544         if (!(intr_loc & ~PCI_EXP_SLTSTA_CC))
 545                 return IRQ_HANDLED;
 546
 547         /* Check MRL Sensor Changed */
 548         if (intr_loc & PCI_EXP_SLTSTA_MRLSC)
 549                 pciehp_handle_switch_change(slot);
 550
 551         /* Check Attention Button Pressed */
 552         if (intr_loc & PCI_EXP_SLTSTA_ABP)
 553                 pciehp_handle_attention_button(slot);
 554
 555         /* Check Presence Detect Changed */
 556         if (intr_loc & PCI_EXP_SLTSTA_PDC)
 557                 pciehp_handle_presence_change(slot);
 558
 559         /* Check Power Fault Detected */
 560         if ((intr_loc & PCI_EXP_SLTSTA_PFD) && !ctrl->power_fault_detected) {
 561                 ctrl->power_fault_detected = 1;
 562                 pciehp_handle_power_fault(slot);
 563         }
 564
 565         if (intr_loc & PCI_EXP_SLTSTA_DLLSC)
 566                 pciehp_handle_linkstate_change(slot);
 567
 568         return IRQ_HANDLED;
 569 }
 570
 571 void pcie_enable_notification(struct controller *ctrl)
 572 {
 573         u16 cmd, mask;
 574
 575         /*
 576          * TBD: Power fault detected software notification support.
 577          *
 578          * Power fault detected software notification is not enabled
 579          * now, because it caused power fault detected interrupt storm
 580          * on some machines. On those machines, power fault detected
 581          * bit in the slot status register was set again immediately
 582          * when it is cleared in the interrupt service routine, and
 583          * next power fault detected interrupt was notified again.
 584          */
 585
 586         /*
 587          * Always enable link events: thus link-up and link-down shall
 588          * always be treated as hotplug and unplug respectively. Enable
 589          * presence detect only if Attention Button is not present.
 590          */
 591         cmd = PCI_EXP_SLTCTL_DLLSCE;
 592         if (ATTN_BUTTN(ctrl))
 593                 cmd |= PCI_EXP_SLTCTL_ABPE;
 594         else
 595                 cmd |= PCI_EXP_SLTCTL_PDCE;
 596         if (MRL_SENS(ctrl))
 597                 cmd |= PCI_EXP_SLTCTL_MRLSCE;
 598         if (!pciehp_poll_mode)
 599                 cmd |= PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE;
 600
 601         mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE |
 602                 PCI_EXP_SLTCTL_MRLSCE | PCI_EXP_SLTCTL_PFDE |
 603                 PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE |
 604                 PCI_EXP_SLTCTL_DLLSCE);
 605
 606         pcie_write_cmd(ctrl, cmd, mask);
 607 }
 608
 609 static void pcie_disable_notification(struct controller *ctrl)
 610 {
 611         u16 mask;
 612
 613         mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE |
 614                 PCI_EXP_SLTCTL_MRLSCE | PCI_EXP_SLTCTL_PFDE |
 615                 PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE |
 616                 PCI_EXP_SLTCTL_DLLSCE);
 617         pcie_write_cmd(ctrl, 0, mask);
 618 }
 619
 620 /*
 621  * pciehp has a 1:1 bus:slot relationship so we ultimately want a secondary
 622  * bus reset of the bridge, but at the same time we want to ensure that it is
 623  * not seen as a hot-unplug, followed by the hot-plug of the device. Thus,
 624  * disable link state notification and presence detection change notification
 625  * momentarily, if we see that they could interfere. Also, clear any spurious
 626  * events after.
 627  */
 628 int pciehp_reset_slot(struct slot *slot, int probe)
 629 {
 630         struct controller *ctrl = slot->ctrl;
 631         struct pci_dev *pdev = ctrl_dev(ctrl);
 632         u16 stat_mask = 0, ctrl_mask = 0;
 633
 634         if (probe)
 635                 return 0;
 636
 637         if (!ATTN_BUTTN(ctrl)) {
 638                 ctrl_mask |= PCI_EXP_SLTCTL_PDCE;
 639                 stat_mask |= PCI_EXP_SLTSTA_PDC;
 640         }
 641         ctrl_mask |= PCI_EXP_SLTCTL_DLLSCE;
 642         stat_mask |= PCI_EXP_SLTSTA_DLLSC;
 643
 644         pcie_write_cmd(ctrl, 0, ctrl_mask);
 645         if (pciehp_poll_mode)
 646                 del_timer_sync(&ctrl->poll_timer);
 647
 648         pci_reset_bridge_secondary_bus(ctrl->pcie->port);
 649
 650         pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, stat_mask);
 651         pcie_write_cmd(ctrl, ctrl_mask, ctrl_mask);
 652         if (pciehp_poll_mode)
 653                 int_poll_timeout(ctrl->poll_timer.data);
 654
 655         return 0;
 656 }
 657
 658 int pcie_init_notification(struct controller *ctrl)
 659 {
 660         if (pciehp_request_irq(ctrl))
 661                 return -1;
 662         pcie_enable_notification(ctrl);
 663         ctrl->notification_enabled = 1;
 664         return 0;
 665 }
 666
 667 static void pcie_shutdown_notification(struct controller *ctrl)
 668 {
 669         if (ctrl->notification_enabled) {
 670                 pcie_disable_notification(ctrl);
 671                 pciehp_free_irq(ctrl);
 672                 ctrl->notification_enabled = 0;
 673         }
 674 }
 675
 676 static int pcie_init_slot(struct controller *ctrl)
 677 {
 678         struct slot *slot;
 679
 680         slot = kzalloc(sizeof(*slot), GFP_KERNEL);
 681         if (!slot)
 682                 return -ENOMEM;
 683
 684         slot->wq = alloc_workqueue("pciehp-%u", 0, 0, PSN(ctrl));
 685         if (!slot->wq)
 686                 goto abort;
 687
 688         slot->ctrl = ctrl;
 689         mutex_init(&slot->lock);
 690         mutex_init(&slot->hotplug_lock);
 691         INIT_DELAYED_WORK(&slot->work, pciehp_queue_pushbutton_work);
 692         ctrl->slot = slot;
 693         return 0;
 694 abort:
 695         kfree(slot);
 696         return -ENOMEM;
 697 }
 698
 699 static void pcie_cleanup_slot(struct controller *ctrl)
 700 {
 701         struct slot *slot = ctrl->slot;
 702         cancel_delayed_work(&slot->work);
 703         destroy_workqueue(slot->wq);
 704         kfree(slot);
 705 }
 706
 707 static inline void dbg_ctrl(struct controller *ctrl)
 708 {
 709         int i;
 710         u16 reg16;
 711         struct pci_dev *pdev = ctrl->pcie->port;
 712
 713         if (!pciehp_debug)
 714                 return;
 715
 716         ctrl_info(ctrl, "Hotplug Controller:\n");
 717         ctrl_info(ctrl, "  Seg/Bus/Dev/Func/IRQ : %s IRQ %d\n",
 718                   pci_name(pdev), pdev->irq);
 719         ctrl_info(ctrl, "  Vendor ID            : 0x%04x\n", pdev->vendor);
 720         ctrl_info(ctrl, "  Device ID            : 0x%04x\n", pdev->device);
 721         ctrl_info(ctrl, "  Subsystem ID         : 0x%04x\n",
 722                   pdev->subsystem_device);
 723         ctrl_info(ctrl, "  Subsystem Vendor ID  : 0x%04x\n",
 724                   pdev->subsystem_vendor);
 725         ctrl_info(ctrl, "  PCIe Cap offset      : 0x%02x\n",
 726                   pci_pcie_cap(pdev));
 727         for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
 728                 if (!pci_resource_len(pdev, i))
 729                         continue;
 730                 ctrl_info(ctrl, "  PCI resource [%d]     : %pR\n",
 731                           i, &pdev->resource[i]);
 732         }
 733         ctrl_info(ctrl, "Slot Capabilities      : 0x%08x\n", ctrl->slot_cap);
 734         ctrl_info(ctrl, "  Physical Slot Number : %d\n", PSN(ctrl));
 735         ctrl_info(ctrl, "  Attention Button     : %3s\n",
 736                   ATTN_BUTTN(ctrl) ? "yes" : "no");
 737         ctrl_info(ctrl, "  Power Controller     : %3s\n",
 738                   POWER_CTRL(ctrl) ? "yes" : "no");
 739         ctrl_info(ctrl, "  MRL Sensor           : %3s\n",
 740                   MRL_SENS(ctrl)   ? "yes" : "no");
 741         ctrl_info(ctrl, "  Attention Indicator  : %3s\n",
 742                   ATTN_LED(ctrl)   ? "yes" : "no");
 743         ctrl_info(ctrl, "  Power Indicator      : %3s\n",
 744                   PWR_LED(ctrl)    ? "yes" : "no");
 745         ctrl_info(ctrl, "  Hot-Plug Surprise    : %3s\n",
 746                   HP_SUPR_RM(ctrl) ? "yes" : "no");
 747         ctrl_info(ctrl, "  EMI Present          : %3s\n",
 748                   EMI(ctrl)        ? "yes" : "no");
 749         ctrl_info(ctrl, "  Command Completed    : %3s\n",
 750                   NO_CMD_CMPL(ctrl) ? "no" : "yes");
 751         pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &reg16);
 752         ctrl_info(ctrl, "Slot Status            : 0x%04x\n", reg16);
 753         pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &reg16);
 754         ctrl_info(ctrl, "Slot Control           : 0x%04x\n", reg16);
 755 }
 756
 757 #define FLAG(x, y)      (((x) & (y)) ? '+' : '-')
 758
 759 struct controller *pcie_init(struct pcie_device *dev)
 760 {
 761         struct controller *ctrl;
 762         u32 slot_cap, link_cap;
 763         struct pci_dev *pdev = dev->port;
 764
 765         ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
 766         if (!ctrl) {
 767                 dev_err(&dev->device, "%s: Out of memory\n", __func__);
 768                 goto abort;
 769         }
 770         ctrl->pcie = dev;
 771         pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &slot_cap);
 772         ctrl->slot_cap = slot_cap;
 773         mutex_init(&ctrl->ctrl_lock);
 774         init_waitqueue_head(&ctrl->queue);
 775         dbg_ctrl(ctrl);
 776         /*
 777          * Controller doesn't notify of command completion if the "No
 778          * Command Completed Support" bit is set in Slot Capability
 779          * register or the controller supports none of power
 780          * controller, attention led, power led and EMI.
 781          */
 782         if (NO_CMD_CMPL(ctrl) ||
 783             !(POWER_CTRL(ctrl) | ATTN_LED(ctrl) | PWR_LED(ctrl) | EMI(ctrl)))
 784                 ctrl->no_cmd_complete = 1;
 785
 786         /* Check if Data Link Layer Link Active Reporting is implemented */
 787         pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &link_cap);
 788         if (link_cap & PCI_EXP_LNKCAP_DLLLARC) {
 789                 ctrl_dbg(ctrl, "Link Active Reporting supported\n");
 790                 ctrl->link_active_reporting = 1;
 791         }
 792
 793         /* Clear all remaining event bits in Slot Status register */
 794         pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
 795                 PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD |
 796                 PCI_EXP_SLTSTA_MRLSC | PCI_EXP_SLTSTA_PDC |
 797                 PCI_EXP_SLTSTA_CC);
 798
 799         /* Disable software notification */
 800         pcie_disable_notification(ctrl);
 801
 802         ctrl_info(ctrl, "Slot #%d AttnBtn%c AttnInd%c PwrInd%c PwrCtrl%c MRL%c Interlock%c NoCompl%c LLActRep%c\n",
 803                 (slot_cap & PCI_EXP_SLTCAP_PSN) >> 19,
 804                 FLAG(slot_cap, PCI_EXP_SLTCAP_ABP),
 805                 FLAG(slot_cap, PCI_EXP_SLTCAP_AIP),
 806                 FLAG(slot_cap, PCI_EXP_SLTCAP_PIP),
 807                 FLAG(slot_cap, PCI_EXP_SLTCAP_PCP),
 808                 FLAG(slot_cap, PCI_EXP_SLTCAP_MRLSP),
 809                 FLAG(slot_cap, PCI_EXP_SLTCAP_EIP),
 810                 FLAG(slot_cap, PCI_EXP_SLTCAP_NCCS),
 811                 FLAG(link_cap, PCI_EXP_LNKCAP_DLLLARC));
 812
 813         if (pcie_init_slot(ctrl))
 814                 goto abort_ctrl;
 815
 816         return ctrl;
 817
 818 abort_ctrl:
 819         kfree(ctrl);
 820 abort:
 821         return NULL;
 822 }
 823
 824 void pciehp_release_ctrl(struct controller *ctrl)
 825 {
 826         pcie_shutdown_notification(ctrl);
 827         pcie_cleanup_slot(ctrl);
 828         kfree(ctrl);
 829 }