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 *slot, const char *buf,
 148                 size_t count)
 149 {
 150         unsigned long llock;
 151         u8 lock;
 152         int retval = 0;
 153
 154         llock = simple_strtoul(buf, NULL, 10);
 155         lock = (u8)(llock & 0xff);
 156
 157         switch (lock) {
 158                 case 0:
 159                 case 1:
 160                         retval = set_lock_status(slot, lock);
 161                         break;
 162                 default:
 163                         err ("%d is an invalid lock value\n", lock);
 164                         retval = -EINVAL;
 165         }
 166         if (retval)
 167                 return retval;
 168         return count;
 169 }
 170
 171 static struct hotplug_slot_attribute hotplug_slot_attr_lock = {
 172         .attr = {.name = "lock", .mode = S_IFREG | S_IRUGO | S_IWUSR},
 173         .show = lock_read_file,
 174         .store = lock_write_file
 175 };
 176
 177 /**
 178  * release_slot - free up the memory used by a slot
 179  * @hotplug_slot: slot to free
 180  */
 181 static void release_slot(struct hotplug_slot *hotplug_slot)
 182 {
 183         dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
 184
 185         kfree(hotplug_slot->info);
 186         kfree(hotplug_slot);
 187 }
 188
 189 static int init_slots(struct controller *ctrl)
 190 {
 191         struct slot *slot;
 192         struct hotplug_slot *hotplug_slot;
 193         struct hotplug_slot_info *info;
 194         int len, dup = 1;
 195         int retval = -ENOMEM;
 196
 197         list_for_each_entry(slot, &ctrl->slot_list, slot_list) {
 198                 hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
 199                 if (!hotplug_slot)
 200                         goto error;
 201
 202                 info = kzalloc(sizeof(*info), GFP_KERNEL);
 203                 if (!info)
 204                         goto error_hpslot;
 205
 206                 /* register this slot with the hotplug pci core */
 207                 hotplug_slot->info = info;
 208                 hotplug_slot->name = slot->name;
 209                 hotplug_slot->private = slot;
 210                 hotplug_slot->release = &release_slot;
 211                 hotplug_slot->ops = &pciehp_hotplug_slot_ops;
 212                 get_power_status(hotplug_slot, &info->power_status);
 213                 get_attention_status(hotplug_slot, &info->attention_status);
 214                 get_latch_status(hotplug_slot, &info->latch_status);
 215                 get_adapter_status(hotplug_slot, &info->adapter_status);
 216                 slot->hotplug_slot = hotplug_slot;
 217
 218                 dbg("Registering bus=%x dev=%x hp_slot=%x sun=%x "
 219                     "slot_device_offset=%x\n", slot->bus, slot->device,
 220                     slot->hp_slot, slot->number, ctrl->slot_device_offset);
 221 duplicate_name:
 222                 retval = pci_hp_register(hotplug_slot,
 223                                          ctrl->pci_dev->subordinate,
 224                                          slot->device);
 225                 if (retval) {
 226                         /*
 227                          * If slot N already exists, we'll try to create
 228                          * slot N-1, N-2 ... N-M, until we overflow.
 229                          */
 230                         if (retval == -EEXIST) {
 231                                 len = snprintf(slot->name, SLOT_NAME_SIZE,
 232                                                "%d-%d", slot->number, dup++);
 233                                 if (len < SLOT_NAME_SIZE)
 234                                         goto duplicate_name;
 235                                 else
 236                                         err("duplicate slot name overflow\n");
 237                         }
 238                         err("pci_hp_register failed with error %d\n", retval);
 239                         goto error_info;
 240                 }
 241                 /* create additional sysfs entries */
 242                 if (EMI(ctrl)) {
 243                         retval = sysfs_create_file(&hotplug_slot->pci_slot->kobj,
 244                                 &hotplug_slot_attr_lock.attr);
 245                         if (retval) {
 246                                 pci_hp_deregister(hotplug_slot);
 247                                 err("cannot create additional sysfs entries\n");
 248                                 goto error_info;
 249                         }
 250                 }
 251         }
 252
 253         return 0;
 254 error_info:
 255         kfree(info);
 256 error_hpslot:
 257         kfree(hotplug_slot);
 258 error:
 259         return retval;
 260 }
 261
 262 static void cleanup_slots(struct controller *ctrl)
 263 {
 264         struct slot *slot;
 265
 266         list_for_each_entry(slot, &ctrl->slot_list, slot_list) {
 267                 if (EMI(ctrl))
 268                         sysfs_remove_file(&slot->hotplug_slot->pci_slot->kobj,
 269                                 &hotplug_slot_attr_lock.attr);
 270                 pci_hp_deregister(slot->hotplug_slot);
 271         }
 272 }
 273
 274 /*
 275  * set_attention_status - Turns the Amber LED for a slot on, off or blink
 276  */
 277 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
 278 {
 279         struct slot *slot = hotplug_slot->private;
 280
 281         dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
 282
 283         hotplug_slot->info->attention_status = status;
 284
 285         if (ATTN_LED(slot->ctrl))
 286                 slot->hpc_ops->set_attention_status(slot, status);
 287
 288         return 0;
 289 }
 290
 291
 292 static int enable_slot(struct hotplug_slot *hotplug_slot)
 293 {
 294         struct slot *slot = hotplug_slot->private;
 295
 296         dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
 297
 298         return pciehp_sysfs_enable_slot(slot);
 299 }
 300
 301
 302 static int disable_slot(struct hotplug_slot *hotplug_slot)
 303 {
 304         struct slot *slot = hotplug_slot->private;
 305
 306         dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
 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         dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
 317
 318         retval = slot->hpc_ops->get_power_status(slot, value);
 319         if (retval < 0)
 320                 *value = hotplug_slot->info->power_status;
 321
 322         return 0;
 323 }
 324
 325 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
 326 {
 327         struct slot *slot = hotplug_slot->private;
 328         int retval;
 329
 330         dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
 331
 332         retval = slot->hpc_ops->get_attention_status(slot, value);
 333         if (retval < 0)
 334                 *value = hotplug_slot->info->attention_status;
 335
 336         return 0;
 337 }
 338
 339 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
 340 {
 341         struct slot *slot = hotplug_slot->private;
 342         int retval;
 343
 344         dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
 345
 346         retval = slot->hpc_ops->get_latch_status(slot, value);
 347         if (retval < 0)
 348                 *value = hotplug_slot->info->latch_status;
 349
 350         return 0;
 351 }
 352
 353 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
 354 {
 355         struct slot *slot = hotplug_slot->private;
 356         int retval;
 357
 358         dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
 359
 360         retval = slot->hpc_ops->get_adapter_status(slot, value);
 361         if (retval < 0)
 362                 *value = hotplug_slot->info->adapter_status;
 363
 364         return 0;
 365 }
 366
 367 static int get_max_bus_speed(struct hotplug_slot *hotplug_slot,
 368                                 enum pci_bus_speed *value)
 369 {
 370         struct slot *slot = hotplug_slot->private;
 371         int retval;
 372
 373         dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
 374
 375         retval = slot->hpc_ops->get_max_bus_speed(slot, value);
 376         if (retval < 0)
 377                 *value = PCI_SPEED_UNKNOWN;
 378
 379         return 0;
 380 }
 381
 382 static int get_cur_bus_speed(struct hotplug_slot *hotplug_slot, enum pci_bus_speed *value)
 383 {
 384         struct slot *slot = hotplug_slot->private;
 385         int retval;
 386
 387         dbg("%s - physical_slot = %s\n", __func__, hotplug_slot->name);
 388
 389         retval = slot->hpc_ops->get_cur_bus_speed(slot, value);
 390         if (retval < 0)
 391                 *value = PCI_SPEED_UNKNOWN;
 392
 393         return 0;
 394 }
 395
 396 static int pciehp_probe(struct pcie_device *dev, const struct pcie_port_service_id *id)
 397 {
 398         int rc;
 399         struct controller *ctrl;
 400         struct slot *t_slot;
 401         u8 value;
 402         struct pci_dev *pdev = dev->port;
 403
 404         if (pciehp_force)
 405                 dbg("Bypassing BIOS check for pciehp use on %s\n",
 406                     pci_name(pdev));
 407         else if (pciehp_get_hp_hw_control_from_firmware(pdev))
 408                 goto err_out_none;
 409
 410         ctrl = pcie_init(dev);
 411         if (!ctrl) {
 412                 dbg("%s: controller initialization failed\n", PCIE_MODULE_NAME);
 413                 goto err_out_none;
 414         }
 415         set_service_data(dev, ctrl);
 416
 417         /* Setup the slot information structures */
 418         rc = init_slots(ctrl);
 419         if (rc) {
 420                 if (rc == -EBUSY)
 421                         warn("%s: slot already registered by another "
 422                                 "hotplug driver\n", PCIE_MODULE_NAME);
 423                 else
 424                         err("%s: slot initialization failed\n",
 425                                 PCIE_MODULE_NAME);
 426                 goto err_out_release_ctlr;
 427         }
 428
 429         t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);
 430
 431         t_slot->hpc_ops->get_adapter_status(t_slot, &value); /* Check if slot is occupied */
 432         if (value && pciehp_force) {
 433                 rc = pciehp_enable_slot(t_slot);
 434                 if (rc) /* -ENODEV: shouldn't happen, but deal with it */
 435                         value = 0;
 436         }
 437         if ((POWER_CTRL(ctrl)) && !value) {
 438                 rc = t_slot->hpc_ops->power_off_slot(t_slot); /* Power off slot if not occupied*/
 439                 if (rc)
 440                         goto err_out_free_ctrl_slot;
 441         }
 442
 443         return 0;
 444
 445 err_out_free_ctrl_slot:
 446         cleanup_slots(ctrl);
 447 err_out_release_ctlr:
 448         ctrl->hpc_ops->release_ctlr(ctrl);
 449 err_out_none:
 450         return -ENODEV;
 451 }
 452
 453 static void pciehp_remove (struct pcie_device *dev)
 454 {
 455         struct controller *ctrl = get_service_data(dev);
 456
 457         cleanup_slots(ctrl);
 458         ctrl->hpc_ops->release_ctlr(ctrl);
 459 }
 460
 461 #ifdef CONFIG_PM
 462 static int pciehp_suspend (struct pcie_device *dev, pm_message_t state)
 463 {
 464         printk("%s ENTRY\n", __func__);
 465         return 0;
 466 }
 467
 468 static int pciehp_resume (struct pcie_device *dev)
 469 {
 470         printk("%s ENTRY\n", __func__);
 471         if (pciehp_force) {
 472                 struct controller *ctrl = get_service_data(dev);
 473                 struct slot *t_slot;
 474                 u8 status;
 475
 476                 /* reinitialize the chipset's event detection logic */
 477                 pcie_enable_notification(ctrl);
 478
 479                 t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);
 480
 481                 /* Check if slot is occupied */
 482                 t_slot->hpc_ops->get_adapter_status(t_slot, &status);
 483                 if (status)
 484                         pciehp_enable_slot(t_slot);
 485                 else
 486                         pciehp_disable_slot(t_slot);
 487         }
 488         return 0;
 489 }
 490 #endif
 491
 492 static struct pcie_port_service_id port_pci_ids[] = { {
 493         .vendor = PCI_ANY_ID,
 494         .device = PCI_ANY_ID,
 495         .port_type = PCIE_ANY_PORT,
 496         .service_type = PCIE_PORT_SERVICE_HP,
 497         .driver_data =  0,
 498         }, { /* end: all zeroes */ }
 499 };
 500 static const char device_name[] = "hpdriver";
 501
 502 static struct pcie_port_service_driver hpdriver_portdrv = {
 503         .name           = (char *)device_name,
 504         .id_table       = &port_pci_ids[0],
 505
 506         .probe          = pciehp_probe,
 507         .remove         = pciehp_remove,
 508
 509 #ifdef  CONFIG_PM
 510         .suspend        = pciehp_suspend,
 511         .resume         = pciehp_resume,
 512 #endif  /* PM */
 513 };
 514
 515 static int __init pcied_init(void)
 516 {
 517         int retval = 0;
 518
 519         retval = pcie_port_service_register(&hpdriver_portdrv);
 520         dbg("pcie_port_service_register = %d\n", retval);
 521         info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
 522         if (retval)
 523                 dbg("%s: Failure to register service\n", __func__);
 524         return retval;
 525 }
 526
 527 static void __exit pcied_cleanup(void)
 528 {
 529         dbg("unload_pciehpd()\n");
 530         pcie_port_service_unregister(&hpdriver_portdrv);
 531         info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
 532 }
 533
 534 module_init(pcied_init);
 535 module_exit(pcied_cleanup);