drivers/pci/hotplug/pciehp_core.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/moduleparam.h>
  32 #include <linux/kernel.h>
  33 #include <linux/types.h>
  34 #include <linux/pci.h>
  35 #include "pciehp.h"
  36 #include <linux/interrupt.h>
  37 #include <linux/time.h>
  38
  39 /* Global variables */
  40 int pciehp_debug;
  41 int pciehp_poll_mode;
  42 int pciehp_poll_time;
  43 int pciehp_force;
  44 struct workqueue_struct *pciehp_wq;
  45
  46 #define DRIVER_VERSION  "0.4"
  47 #define DRIVER_AUTHOR   "Dan Zink <dan.zink@compaq.com>, Greg Kroah-Hartman <greg@kroah.com>, Dely Sy <dely.l.sy@intel.com>"
  48 #define DRIVER_DESC     "PCI Express Hot Plug Controller Driver"
  49
  50 MODULE_AUTHOR(DRIVER_AUTHOR);
  51 MODULE_DESCRIPTION(DRIVER_DESC);
  52 MODULE_LICENSE("GPL");
  53
  54 module_param(pciehp_debug, bool, 0644);
  55 module_param(pciehp_poll_mode, bool, 0644);
  56 module_param(pciehp_poll_time, int, 0644);
  57 module_param(pciehp_force, bool, 0644);
  58 MODULE_PARM_DESC(pciehp_debug, "Debugging mode enabled or not");
  59 MODULE_PARM_DESC(pciehp_poll_mode, "Using polling mechanism for hot-plug events or not");
  60 MODULE_PARM_DESC(pciehp_poll_time, "Polling mechanism frequency, in seconds");
  61 MODULE_PARM_DESC(pciehp_force, "Force pciehp, even if _OSC and OSHP are missing");
  62
  63 #define PCIE_MODULE_NAME "pciehp"
  64
  65 static int set_attention_status (struct hotplug_slot *slot, u8 value);
  66 static int enable_slot          (struct hotplug_slot *slot);
  67 static int disable_slot         (struct hotplug_slot *slot);
  68 static int get_power_status     (struct hotplug_slot *slot, u8 *value);
  69 static int get_attention_status (struct hotplug_slot *slot, u8 *value);
  70 static int get_latch_status     (struct hotplug_slot *slot, u8 *value);
  71 static int get_adapter_status   (struct hotplug_slot *slot, u8 *value);
  72 static int get_max_bus_speed    (struct hotplug_slot *slot, enum pci_bus_speed *value);
  73 static int get_cur_bus_speed    (struct hotplug_slot *slot, enum pci_bus_speed *value);
  74
  75 static struct hotplug_slot_ops pciehp_hotplug_slot_ops = {
  76         .owner =                THIS_MODULE,
  77         .set_attention_status = set_attention_status,
  78         .enable_slot =          enable_slot,
  79         .disable_slot =         disable_slot,
  80         .get_power_status =     get_power_status,
  81         .get_attention_status = get_attention_status,
  82         .get_latch_status =     get_latch_status,
  83         .get_adapter_status =   get_adapter_status,
  84         .get_max_bus_speed =    get_max_bus_speed,
  85         .get_cur_bus_speed =    get_cur_bus_speed,
  86 };
  87
  88 /*
  89  * Check the status of the Electro Mechanical Interlock (EMI)
  90  */
  91 static int get_lock_status(struct hotplug_slot *hotplug_slot, u8 *value)
  92 {
  93         struct slot *slot = hotplug_slot->private;
  94         return (slot->hpc_ops->get_emi_status(slot, value));
  95 }
  96
  97 /*
  98  * sysfs interface for the Electro Mechanical Interlock (EMI)
  99  * 1 == locked, 0 == unlocked
 100  */
 101 static ssize_t lock_read_file(struct hotplug_slot *slot, char *buf)
 102 {
 103         int retval;
 104         u8 value;
 105
 106         retval = get_lock_status(slot, &value);
 107         if (retval)
 108                 goto lock_read_exit;
 109         retval = sprintf (buf, "%d\n", value);
 110
 111 lock_read_exit:
 112         return retval;
 113 }
 114
 115 /*
 116  * Change the status of the Electro Mechanical Interlock (EMI)
 117  * This is a toggle - in addition there must be at least 1 second
 118  * in between toggles.
 119  */
 120 static int set_lock_status(struct hotplug_slot *hotplug_slot, u8 status)
 121 {
 122         struct slot *slot = hotplug_slot->private;
 123         int retval;
 124         u8 value;
 125
 126         mutex_lock(&slot->ctrl->crit_sect);
 127
 128         /* has it been >1 sec since our last toggle? */
 129         if ((get_seconds() - slot->last_emi_toggle) < 1)
 130                 return -EINVAL;
 131
 132         /* see what our current state is */
 133         retval = get_lock_status(hotplug_slot, &value);
 134         if (retval || (value == status))
 135                 goto set_lock_exit;
 136
 137         slot->hpc_ops->toggle_emi(slot);
 138 set_lock_exit:
 139         mutex_unlock(&slot->ctrl->crit_sect);
 140         return 0;
 141 }
 142
 143 /*
 144  * sysfs interface which allows the user to toggle the Electro Mechanical
 145  * Interlock.  Valid values are either 0 or 1.  0 == unlock, 1 == lock
 146  */
 147 static ssize_t lock_write_file(struct hotplug_slot *hotplug_slot,
 148                 const char *buf, size_t count)
 149 {
 150         struct slot *slot = hotplug_slot->private;
 151         unsigned long llock;
 152         u8 lock;
 153         int retval = 0;
 154
 155         llock = simple_strtoul(buf, NULL, 10);
 156         lock = (u8)(llock & 0xff);
 157
 158         switch (lock) {
 159                 case 0:
 160                 case 1:
 161                         retval = set_lock_status(hotplug_slot, lock);
 162                         break;
 163                 default:
 164                         ctrl_err(slot->ctrl, "%d is an invalid lock value\n",
 165                                  lock);
 166                         retval = -EINVAL;
 167         }
 168         if (retval)
 169                 return retval;
 170         return count;
 171 }
 172
 173 static struct hotplug_slot_attribute hotplug_slot_attr_lock = {
 174         .attr = {.name = "lock", .mode = S_IFREG | S_IRUGO | S_IWUSR},
 175         .show = lock_read_file,
 176         .store = lock_write_file
 177 };
 178
 179 /**
 180  * release_slot - free up the memory used by a slot
 181  * @hotplug_slot: slot to free
 182  */
 183 static void release_slot(struct hotplug_slot *hotplug_slot)
 184 {
 185         struct slot *slot = hotplug_slot->private;
 186
 187         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 188                  __func__, hotplug_slot_name(hotplug_slot));
 189
 190         kfree(hotplug_slot->info);
 191         kfree(hotplug_slot);
 192 }
 193
 194 static int init_slots(struct controller *ctrl)
 195 {
 196         struct slot *slot;
 197         struct hotplug_slot *hotplug_slot;
 198         struct hotplug_slot_info *info;
 199         char name[SLOT_NAME_SIZE];
 200         int retval = -ENOMEM;
 201
 202         list_for_each_entry(slot, &ctrl->slot_list, slot_list) {
 203                 hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
 204                 if (!hotplug_slot)
 205                         goto error;
 206
 207                 info = kzalloc(sizeof(*info), GFP_KERNEL);
 208                 if (!info)
 209                         goto error_hpslot;
 210
 211                 /* register this slot with the hotplug pci core */
 212                 hotplug_slot->info = info;
 213                 hotplug_slot->private = slot;
 214                 hotplug_slot->release = &release_slot;
 215                 hotplug_slot->ops = &pciehp_hotplug_slot_ops;
 216                 slot->hotplug_slot = hotplug_slot;
 217                 snprintf(name, SLOT_NAME_SIZE, "%u", slot->number);
 218
 219                 ctrl_dbg(ctrl, "Registering domain:bus:dev=%04x:%02x:%02x "
 220                          "hp_slot=%x sun=%x slot_device_offset=%x\n",
 221                          pci_domain_nr(ctrl->pci_dev->subordinate),
 222                          slot->bus, slot->device, slot->hp_slot, slot->number,
 223                          ctrl->slot_device_offset);
 224                 retval = pci_hp_register(hotplug_slot,
 225                                          ctrl->pci_dev->subordinate,
 226                                          slot->device,
 227                                          name);
 228                 if (retval) {
 229                         ctrl_err(ctrl, "pci_hp_register failed with error %d\n",
 230                                  retval);
 231                         goto error_info;
 232                 }
 233                 get_power_status(hotplug_slot, &info->power_status);
 234                 get_attention_status(hotplug_slot, &info->attention_status);
 235                 get_latch_status(hotplug_slot, &info->latch_status);
 236                 get_adapter_status(hotplug_slot, &info->adapter_status);
 237                 /* create additional sysfs entries */
 238                 if (EMI(ctrl)) {
 239                         retval = sysfs_create_file(&hotplug_slot->pci_slot->kobj,
 240                                 &hotplug_slot_attr_lock.attr);
 241                         if (retval) {
 242                                 pci_hp_deregister(hotplug_slot);
 243                                 ctrl_err(ctrl, "Cannot create additional sysfs "
 244                                          "entries\n");
 245                                 goto error_info;
 246                         }
 247                 }
 248         }
 249
 250         return 0;
 251 error_info:
 252         kfree(info);
 253 error_hpslot:
 254         kfree(hotplug_slot);
 255 error:
 256         return retval;
 257 }
 258
 259 static void cleanup_slots(struct controller *ctrl)
 260 {
 261         struct slot *slot;
 262
 263         list_for_each_entry(slot, &ctrl->slot_list, slot_list) {
 264                 if (EMI(ctrl))
 265                         sysfs_remove_file(&slot->hotplug_slot->pci_slot->kobj,
 266                                 &hotplug_slot_attr_lock.attr);
 267                 pci_hp_deregister(slot->hotplug_slot);
 268         }
 269 }
 270
 271 /*
 272  * set_attention_status - Turns the Amber LED for a slot on, off or blink
 273  */
 274 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
 275 {
 276         struct slot *slot = hotplug_slot->private;
 277
 278         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 279                   __func__, slot_name(slot));
 280
 281         hotplug_slot->info->attention_status = status;
 282
 283         if (ATTN_LED(slot->ctrl))
 284                 slot->hpc_ops->set_attention_status(slot, status);
 285
 286         return 0;
 287 }
 288
 289
 290 static int enable_slot(struct hotplug_slot *hotplug_slot)
 291 {
 292         struct slot *slot = hotplug_slot->private;
 293
 294         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 295                  __func__, slot_name(slot));
 296
 297         return pciehp_sysfs_enable_slot(slot);
 298 }
 299
 300
 301 static int disable_slot(struct hotplug_slot *hotplug_slot)
 302 {
 303         struct slot *slot = hotplug_slot->private;
 304
 305         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 306                   __func__, slot_name(slot));
 307
 308         return pciehp_sysfs_disable_slot(slot);
 309 }
 310
 311 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
 312 {
 313         struct slot *slot = hotplug_slot->private;
 314         int retval;
 315
 316         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 317                   __func__, slot_name(slot));
 318
 319         retval = slot->hpc_ops->get_power_status(slot, value);
 320         if (retval < 0)
 321                 *value = hotplug_slot->info->power_status;
 322
 323         return 0;
 324 }
 325
 326 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
 327 {
 328         struct slot *slot = hotplug_slot->private;
 329         int retval;
 330
 331         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 332                   __func__, slot_name(slot));
 333
 334         retval = slot->hpc_ops->get_attention_status(slot, value);
 335         if (retval < 0)
 336                 *value = hotplug_slot->info->attention_status;
 337
 338         return 0;
 339 }
 340
 341 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
 342 {
 343         struct slot *slot = hotplug_slot->private;
 344         int retval;
 345
 346         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 347                  __func__, slot_name(slot));
 348
 349         retval = slot->hpc_ops->get_latch_status(slot, value);
 350         if (retval < 0)
 351                 *value = hotplug_slot->info->latch_status;
 352
 353         return 0;
 354 }
 355
 356 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
 357 {
 358         struct slot *slot = hotplug_slot->private;
 359         int retval;
 360
 361         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 362                  __func__, slot_name(slot));
 363
 364         retval = slot->hpc_ops->get_adapter_status(slot, value);
 365         if (retval < 0)
 366                 *value = hotplug_slot->info->adapter_status;
 367
 368         return 0;
 369 }
 370
 371 static int get_max_bus_speed(struct hotplug_slot *hotplug_slot,
 372                                 enum pci_bus_speed *value)
 373 {
 374         struct slot *slot = hotplug_slot->private;
 375         int retval;
 376
 377         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 378                  __func__, slot_name(slot));
 379
 380         retval = slot->hpc_ops->get_max_bus_speed(slot, value);
 381         if (retval < 0)
 382                 *value = PCI_SPEED_UNKNOWN;
 383
 384         return 0;
 385 }
 386
 387 static int get_cur_bus_speed(struct hotplug_slot *hotplug_slot, enum pci_bus_speed *value)
 388 {
 389         struct slot *slot = hotplug_slot->private;
 390         int retval;
 391
 392         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 393                  __func__, slot_name(slot));
 394
 395         retval = slot->hpc_ops->get_cur_bus_speed(slot, value);
 396         if (retval < 0)
 397                 *value = PCI_SPEED_UNKNOWN;
 398
 399         return 0;
 400 }
 401
 402 static int pciehp_probe(struct pcie_device *dev, const struct pcie_port_service_id *id)
 403 {
 404         int rc;
 405         struct controller *ctrl;
 406         struct slot *t_slot;
 407         u8 value;
 408         struct pci_dev *pdev = dev->port;
 409
 410         if (pciehp_force)
 411                 dev_info(&dev->device,
 412                          "Bypassing BIOS check for pciehp use on %s\n",
 413                          pci_name(pdev));
 414         else if (pciehp_get_hp_hw_control_from_firmware(pdev))
 415                 goto err_out_none;
 416
 417         ctrl = pcie_init(dev);
 418         if (!ctrl) {
 419                 dev_err(&dev->device, "Controller initialization failed\n");
 420                 goto err_out_none;
 421         }
 422         set_service_data(dev, ctrl);
 423
 424         /* Setup the slot information structures */
 425         rc = init_slots(ctrl);
 426         if (rc) {
 427                 if (rc == -EBUSY)
 428                         ctrl_warn(ctrl, "Slot already registered by another "
 429                                   "hotplug driver\n");
 430                 else
 431                         ctrl_err(ctrl, "Slot initialization failed\n");
 432                 goto err_out_release_ctlr;
 433         }
 434
 435         /* Check if slot is occupied */
 436         t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);
 437         t_slot->hpc_ops->get_adapter_status(t_slot, &value);
 438         if (value) {
 439                 if (pciehp_force)
 440                         pciehp_enable_slot(t_slot);
 441         } else {
 442                 /* Power off slot if not occupied */
 443                 if (POWER_CTRL(ctrl)) {
 444                         rc = t_slot->hpc_ops->power_off_slot(t_slot);
 445                         if (rc)
 446                                 goto err_out_free_ctrl_slot;
 447                 }
 448         }
 449
 450         return 0;
 451
 452 err_out_free_ctrl_slot:
 453         cleanup_slots(ctrl);
 454 err_out_release_ctlr:
 455         ctrl->hpc_ops->release_ctlr(ctrl);
 456 err_out_none:
 457         return -ENODEV;
 458 }
 459
 460 static void pciehp_remove (struct pcie_device *dev)
 461 {
 462         struct controller *ctrl = get_service_data(dev);
 463
 464         cleanup_slots(ctrl);
 465         ctrl->hpc_ops->release_ctlr(ctrl);
 466 }
 467
 468 #ifdef CONFIG_PM
 469 static int pciehp_suspend (struct pcie_device *dev, pm_message_t state)
 470 {
 471         dev_info(&dev->device, "%s ENTRY\n", __func__);
 472         return 0;
 473 }
 474
 475 static int pciehp_resume (struct pcie_device *dev)
 476 {
 477         dev_info(&dev->device, "%s ENTRY\n", __func__);
 478         if (pciehp_force) {
 479                 struct controller *ctrl = get_service_data(dev);
 480                 struct slot *t_slot;
 481                 u8 status;
 482
 483                 /* reinitialize the chipset's event detection logic */
 484                 pcie_enable_notification(ctrl);
 485
 486                 t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);
 487
 488                 /* Check if slot is occupied */
 489                 t_slot->hpc_ops->get_adapter_status(t_slot, &status);
 490                 if (status)
 491                         pciehp_enable_slot(t_slot);
 492                 else
 493                         pciehp_disable_slot(t_slot);
 494         }
 495         return 0;
 496 }
 497 #endif
 498
 499 static struct pcie_port_service_id port_pci_ids[] = { {
 500         .vendor = PCI_ANY_ID,
 501         .device = PCI_ANY_ID,
 502         .port_type = PCIE_ANY_PORT,
 503         .service_type = PCIE_PORT_SERVICE_HP,
 504         .driver_data =  0,
 505         }, { /* end: all zeroes */ }
 506 };
 507
 508 static struct pcie_port_service_driver hpdriver_portdrv = {
 509         .name           = PCIE_MODULE_NAME,
 510         .id_table       = &port_pci_ids[0],
 511
 512         .probe          = pciehp_probe,
 513         .remove         = pciehp_remove,
 514
 515 #ifdef  CONFIG_PM
 516         .suspend        = pciehp_suspend,
 517         .resume         = pciehp_resume,
 518 #endif  /* PM */
 519 };
 520
 521 static int __init pcied_init(void)
 522 {
 523         int retval = 0;
 524
 525         pciehp_firmware_init();
 526         retval = pcie_port_service_register(&hpdriver_portdrv);
 527         dbg("pcie_port_service_register = %d\n", retval);
 528         info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
 529         if (retval)
 530                 dbg("Failure to register service\n");
 531         return retval;
 532 }
 533
 534 static void __exit pcied_cleanup(void)
 535 {
 536         dbg("unload_pciehpd()\n");
 537         pcie_port_service_unregister(&hpdriver_portdrv);
 538         info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
 539 }
 540
 541 module_init(pcied_init);
 542 module_exit(pcied_cleanup);