drivers/edac/edac_pci_sysfs.c

   1 /*
   2  * (C) 2005, 2006 Linux Networx (http://lnxi.com)
   3  * This file may be distributed under the terms of the
   4  * GNU General Public License.
   5  *
   6  * Written Doug Thompson <norsk5@xmission.com>
   7  *
   8  */
   9 #include <linux/module.h>
  10 #include <linux/edac.h>
  11 #include <linux/slab.h>
  12 #include <linux/ctype.h>
  13
  14 #include "edac_pci.h"
  15 #include "edac_module.h"
  16
  17 #define EDAC_PCI_SYMLINK        "device"
  18
  19 /* data variables exported via sysfs */
  20 static int check_pci_errors;            /* default NO check PCI parity */
  21 static int edac_pci_panic_on_pe;        /* default NO panic on PCI Parity */
  22 static int edac_pci_log_pe = 1;         /* log PCI parity errors */
  23 static int edac_pci_log_npe = 1;        /* log PCI non-parity error errors */
  24 static int edac_pci_poll_msec = 1000;   /* one second workq period */
  25
  26 static atomic_t pci_parity_count = ATOMIC_INIT(0);
  27 static atomic_t pci_nonparity_count = ATOMIC_INIT(0);
  28
  29 static struct kobject *edac_pci_top_main_kobj;
  30 static atomic_t edac_pci_sysfs_refcount = ATOMIC_INIT(0);
  31
  32 /* getter functions for the data variables */
  33 int edac_pci_get_check_errors(void)
  34 {
  35         return check_pci_errors;
  36 }
  37
  38 static int edac_pci_get_log_pe(void)
  39 {
  40         return edac_pci_log_pe;
  41 }
  42
  43 static int edac_pci_get_log_npe(void)
  44 {
  45         return edac_pci_log_npe;
  46 }
  47
  48 static int edac_pci_get_panic_on_pe(void)
  49 {
  50         return edac_pci_panic_on_pe;
  51 }
  52
  53 int edac_pci_get_poll_msec(void)
  54 {
  55         return edac_pci_poll_msec;
  56 }
  57
  58 /**************************** EDAC PCI sysfs instance *******************/
  59 static ssize_t instance_pe_count_show(struct edac_pci_ctl_info *pci, char *data)
  60 {
  61         return sprintf(data, "%u\n", atomic_read(&pci->counters.pe_count));
  62 }
  63
  64 static ssize_t instance_npe_count_show(struct edac_pci_ctl_info *pci,
  65                                 char *data)
  66 {
  67         return sprintf(data, "%u\n", atomic_read(&pci->counters.npe_count));
  68 }
  69
  70 #define to_instance(k) container_of(k, struct edac_pci_ctl_info, kobj)
  71 #define to_instance_attr(a) container_of(a, struct instance_attribute, attr)
  72
  73 /* DEVICE instance kobject release() function */
  74 static void edac_pci_instance_release(struct kobject *kobj)
  75 {
  76         struct edac_pci_ctl_info *pci;
  77
  78         edac_dbg(0, "\n");
  79
  80         /* Form pointer to containing struct, the pci control struct */
  81         pci = to_instance(kobj);
  82
  83         /* decrement reference count on top main kobj */
  84         kobject_put(edac_pci_top_main_kobj);
  85
  86         kfree(pci);     /* Free the control struct */
  87 }
  88
  89 /* instance specific attribute structure */
  90 struct instance_attribute {
  91         struct attribute attr;
  92         ssize_t(*show) (struct edac_pci_ctl_info *, char *);
  93         ssize_t(*store) (struct edac_pci_ctl_info *, const char *, size_t);
  94 };
  95
  96 /* Function to 'show' fields from the edac_pci 'instance' structure */
  97 static ssize_t edac_pci_instance_show(struct kobject *kobj,
  98                                 struct attribute *attr, char *buffer)
  99 {
 100         struct edac_pci_ctl_info *pci = to_instance(kobj);
 101         struct instance_attribute *instance_attr = to_instance_attr(attr);
 102
 103         if (instance_attr->show)
 104                 return instance_attr->show(pci, buffer);
 105         return -EIO;
 106 }
 107
 108 /* Function to 'store' fields into the edac_pci 'instance' structure */
 109 static ssize_t edac_pci_instance_store(struct kobject *kobj,
 110                                 struct attribute *attr,
 111                                 const char *buffer, size_t count)
 112 {
 113         struct edac_pci_ctl_info *pci = to_instance(kobj);
 114         struct instance_attribute *instance_attr = to_instance_attr(attr);
 115
 116         if (instance_attr->store)
 117                 return instance_attr->store(pci, buffer, count);
 118         return -EIO;
 119 }
 120
 121 /* fs_ops table */
 122 static const struct sysfs_ops pci_instance_ops = {
 123         .show = edac_pci_instance_show,
 124         .store = edac_pci_instance_store
 125 };
 126
 127 #define INSTANCE_ATTR(_name, _mode, _show, _store)      \
 128 static struct instance_attribute attr_instance_##_name = {      \
 129         .attr   = {.name = __stringify(_name), .mode = _mode }, \
 130         .show   = _show,                                        \
 131         .store  = _store,                                       \
 132 };
 133
 134 INSTANCE_ATTR(pe_count, S_IRUGO, instance_pe_count_show, NULL);
 135 INSTANCE_ATTR(npe_count, S_IRUGO, instance_npe_count_show, NULL);
 136
 137 /* pci instance attributes */
 138 static struct attribute *pci_instance_attrs[] = {
 139         &attr_instance_pe_count.attr,
 140         &attr_instance_npe_count.attr,
 141         NULL
 142 };
 143 ATTRIBUTE_GROUPS(pci_instance);
 144
 145 /* the ktype for a pci instance */
 146 static struct kobj_type ktype_pci_instance = {
 147         .release = edac_pci_instance_release,
 148         .sysfs_ops = &pci_instance_ops,
 149         .default_groups = pci_instance_groups,
 150 };
 151
 152 /*
 153  * edac_pci_create_instance_kobj
 154  *
 155  *      construct one EDAC PCI instance's kobject for use
 156  */
 157 static int edac_pci_create_instance_kobj(struct edac_pci_ctl_info *pci, int idx)
 158 {
 159         struct kobject *main_kobj;
 160         int err;
 161
 162         edac_dbg(0, "\n");
 163
 164         /* First bump the ref count on the top main kobj, which will
 165          * track the number of PCI instances we have, and thus nest
 166          * properly on keeping the module loaded
 167          */
 168         main_kobj = kobject_get(edac_pci_top_main_kobj);
 169         if (!main_kobj) {
 170                 err = -ENODEV;
 171                 goto error_out;
 172         }
 173
 174         /* And now register this new kobject under the main kobj */
 175         err = kobject_init_and_add(&pci->kobj, &ktype_pci_instance,
 176                                    edac_pci_top_main_kobj, "pci%d", idx);
 177         if (err != 0) {
 178                 edac_dbg(2, "failed to register instance pci%d\n", idx);
 179                 kobject_put(edac_pci_top_main_kobj);
 180                 goto error_out;
 181         }
 182
 183         kobject_uevent(&pci->kobj, KOBJ_ADD);
 184         edac_dbg(1, "Register instance 'pci%d' kobject\n", idx);
 185
 186         return 0;
 187
 188         /* Error unwind statck */
 189 error_out:
 190         return err;
 191 }
 192
 193 /*
 194  * edac_pci_unregister_sysfs_instance_kobj
 195  *
 196  *      unregister the kobj for the EDAC PCI instance
 197  */
 198 static void edac_pci_unregister_sysfs_instance_kobj(
 199                         struct edac_pci_ctl_info *pci)
 200 {
 201         edac_dbg(0, "\n");
 202
 203         /* Unregister the instance kobject and allow its release
 204          * function release the main reference count and then
 205          * kfree the memory
 206          */
 207         kobject_put(&pci->kobj);
 208 }
 209
 210 /***************************** EDAC PCI sysfs root **********************/
 211 #define to_edacpci(k) container_of(k, struct edac_pci_ctl_info, kobj)
 212 #define to_edacpci_attr(a) container_of(a, struct edac_pci_attr, attr)
 213
 214 /* simple show/store functions for attributes */
 215 static ssize_t edac_pci_int_show(void *ptr, char *buffer)
 216 {
 217         int *value = ptr;
 218         return sprintf(buffer, "%d\n", *value);
 219 }
 220
 221 static ssize_t edac_pci_int_store(void *ptr, const char *buffer, size_t count)
 222 {
 223         int *value = ptr;
 224
 225         if (isdigit(*buffer))
 226                 *value = simple_strtoul(buffer, NULL, 0);
 227
 228         return count;
 229 }
 230
 231 struct edac_pci_dev_attribute {
 232         struct attribute attr;
 233         void *value;
 234          ssize_t(*show) (void *, char *);
 235          ssize_t(*store) (void *, const char *, size_t);
 236 };
 237
 238 /* Set of show/store abstract level functions for PCI Parity object */
 239 static ssize_t edac_pci_dev_show(struct kobject *kobj, struct attribute *attr,
 240                                  char *buffer)
 241 {
 242         struct edac_pci_dev_attribute *edac_pci_dev;
 243         edac_pci_dev = (struct edac_pci_dev_attribute *)attr;
 244
 245         if (edac_pci_dev->show)
 246                 return edac_pci_dev->show(edac_pci_dev->value, buffer);
 247         return -EIO;
 248 }
 249
 250 static ssize_t edac_pci_dev_store(struct kobject *kobj,
 251                                 struct attribute *attr, const char *buffer,
 252                                 size_t count)
 253 {
 254         struct edac_pci_dev_attribute *edac_pci_dev;
 255         edac_pci_dev = (struct edac_pci_dev_attribute *)attr;
 256
 257         if (edac_pci_dev->store)
 258                 return edac_pci_dev->store(edac_pci_dev->value, buffer, count);
 259         return -EIO;
 260 }
 261
 262 static const struct sysfs_ops edac_pci_sysfs_ops = {
 263         .show = edac_pci_dev_show,
 264         .store = edac_pci_dev_store
 265 };
 266
 267 #define EDAC_PCI_ATTR(_name,_mode,_show,_store)                 \
 268 static struct edac_pci_dev_attribute edac_pci_attr_##_name = {          \
 269         .attr = {.name = __stringify(_name), .mode = _mode },   \
 270         .value  = &_name,                                       \
 271         .show   = _show,                                        \
 272         .store  = _store,                                       \
 273 };
 274
 275 #define EDAC_PCI_STRING_ATTR(_name,_data,_mode,_show,_store)    \
 276 static struct edac_pci_dev_attribute edac_pci_attr_##_name = {          \
 277         .attr = {.name = __stringify(_name), .mode = _mode },   \
 278         .value  = _data,                                        \
 279         .show   = _show,                                        \
 280         .store  = _store,                                       \
 281 };
 282
 283 /* PCI Parity control files */
 284 EDAC_PCI_ATTR(check_pci_errors, S_IRUGO | S_IWUSR, edac_pci_int_show,
 285         edac_pci_int_store);
 286 EDAC_PCI_ATTR(edac_pci_log_pe, S_IRUGO | S_IWUSR, edac_pci_int_show,
 287         edac_pci_int_store);
 288 EDAC_PCI_ATTR(edac_pci_log_npe, S_IRUGO | S_IWUSR, edac_pci_int_show,
 289         edac_pci_int_store);
 290 EDAC_PCI_ATTR(edac_pci_panic_on_pe, S_IRUGO | S_IWUSR, edac_pci_int_show,
 291         edac_pci_int_store);
 292 EDAC_PCI_ATTR(pci_parity_count, S_IRUGO, edac_pci_int_show, NULL);
 293 EDAC_PCI_ATTR(pci_nonparity_count, S_IRUGO, edac_pci_int_show, NULL);
 294
 295 /* Base Attributes of the memory ECC object */
 296 static struct attribute *edac_pci_attrs[] = {
 297         &edac_pci_attr_check_pci_errors.attr,
 298         &edac_pci_attr_edac_pci_log_pe.attr,
 299         &edac_pci_attr_edac_pci_log_npe.attr,
 300         &edac_pci_attr_edac_pci_panic_on_pe.attr,
 301         &edac_pci_attr_pci_parity_count.attr,
 302         &edac_pci_attr_pci_nonparity_count.attr,
 303         NULL,
 304 };
 305 ATTRIBUTE_GROUPS(edac_pci);
 306
 307 /*
 308  * edac_pci_release_main_kobj
 309  *
 310  *      This release function is called when the reference count to the
 311  *      passed kobj goes to zero.
 312  *
 313  *      This kobj is the 'main' kobject that EDAC PCI instances
 314  *      link to, and thus provide for proper nesting counts
 315  */
 316 static void edac_pci_release_main_kobj(struct kobject *kobj)
 317 {
 318         edac_dbg(0, "here to module_put(THIS_MODULE)\n");
 319
 320         kfree(kobj);
 321
 322         /* last reference to top EDAC PCI kobject has been removed,
 323          * NOW release our ref count on the core module
 324          */
 325         module_put(THIS_MODULE);
 326 }
 327
 328 /* ktype struct for the EDAC PCI main kobj */
 329 static struct kobj_type ktype_edac_pci_main_kobj = {
 330         .release = edac_pci_release_main_kobj,
 331         .sysfs_ops = &edac_pci_sysfs_ops,
 332         .default_groups = edac_pci_groups,
 333 };
 334
 335 /**
 336  * edac_pci_main_kobj_setup: Setup the sysfs for EDAC PCI attributes.
 337  */
 338 static int edac_pci_main_kobj_setup(void)
 339 {
 340         int err = -ENODEV;
 341         const struct bus_type *edac_subsys;
 342         struct device *dev_root;
 343
 344         edac_dbg(0, "\n");
 345
 346         /* check and count if we have already created the main kobject */
 347         if (atomic_inc_return(&edac_pci_sysfs_refcount) != 1)
 348                 return 0;
 349
 350         /* First time, so create the main kobject and its
 351          * controls and attributes
 352          */
 353         edac_subsys = edac_get_sysfs_subsys();
 354
 355         /* Bump the reference count on this module to ensure the
 356          * modules isn't unloaded until we deconstruct the top
 357          * level main kobj for EDAC PCI
 358          */
 359         if (!try_module_get(THIS_MODULE)) {
 360                 edac_dbg(1, "try_module_get() failed\n");
 361                 goto decrement_count_fail;
 362         }
 363
 364         edac_pci_top_main_kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
 365         if (!edac_pci_top_main_kobj) {
 366                 edac_dbg(1, "Failed to allocate\n");
 367                 err = -ENOMEM;
 368                 goto kzalloc_fail;
 369         }
 370
 371         /* Instanstiate the pci object */
 372         dev_root = bus_get_dev_root(edac_subsys);
 373         if (dev_root) {
 374                 err = kobject_init_and_add(edac_pci_top_main_kobj,
 375                                            &ktype_edac_pci_main_kobj,
 376                                            &dev_root->kobj, "pci");
 377                 put_device(dev_root);
 378         }
 379         if (err) {
 380                 edac_dbg(1, "Failed to register '.../edac/pci'\n");
 381                 goto kobject_init_and_add_fail;
 382         }
 383
 384         /* At this point, to 'release' the top level kobject
 385          * for EDAC PCI, then edac_pci_main_kobj_teardown()
 386          * must be used, for resources to be cleaned up properly
 387          */
 388         kobject_uevent(edac_pci_top_main_kobj, KOBJ_ADD);
 389         edac_dbg(1, "Registered '.../edac/pci' kobject\n");
 390
 391         return 0;
 392
 393         /* Error unwind statck */
 394 kobject_init_and_add_fail:
 395         kobject_put(edac_pci_top_main_kobj);
 396
 397 kzalloc_fail:
 398         module_put(THIS_MODULE);
 399
 400 decrement_count_fail:
 401         /* if are on this error exit, nothing to tear down */
 402         atomic_dec(&edac_pci_sysfs_refcount);
 403
 404         return err;
 405 }
 406
 407 /*
 408  * edac_pci_main_kobj_teardown()
 409  *
 410  *      if no longer linked (needed) remove the top level EDAC PCI
 411  *      kobject with its controls and attributes
 412  */
 413 static void edac_pci_main_kobj_teardown(void)
 414 {
 415         edac_dbg(0, "\n");
 416
 417         /* Decrement the count and only if no more controller instances
 418          * are connected perform the unregisteration of the top level
 419          * main kobj
 420          */
 421         if (atomic_dec_return(&edac_pci_sysfs_refcount) == 0) {
 422                 edac_dbg(0, "called kobject_put on main kobj\n");
 423                 kobject_put(edac_pci_top_main_kobj);
 424         }
 425 }
 426
 427 int edac_pci_create_sysfs(struct edac_pci_ctl_info *pci)
 428 {
 429         int err;
 430         struct kobject *edac_kobj = &pci->kobj;
 431
 432         edac_dbg(0, "idx=%d\n", pci->pci_idx);
 433
 434         /* create the top main EDAC PCI kobject, IF needed */
 435         err = edac_pci_main_kobj_setup();
 436         if (err)
 437                 return err;
 438
 439         /* Create this instance's kobject under the MAIN kobject */
 440         err = edac_pci_create_instance_kobj(pci, pci->pci_idx);
 441         if (err)
 442                 goto unregister_cleanup;
 443
 444         err = sysfs_create_link(edac_kobj, &pci->dev->kobj, EDAC_PCI_SYMLINK);
 445         if (err) {
 446                 edac_dbg(0, "sysfs_create_link() returned err= %d\n", err);
 447                 goto symlink_fail;
 448         }
 449
 450         return 0;
 451
 452         /* Error unwind stack */
 453 symlink_fail:
 454         edac_pci_unregister_sysfs_instance_kobj(pci);
 455
 456 unregister_cleanup:
 457         edac_pci_main_kobj_teardown();
 458
 459         return err;
 460 }
 461
 462 void edac_pci_remove_sysfs(struct edac_pci_ctl_info *pci)
 463 {
 464         edac_dbg(0, "index=%d\n", pci->pci_idx);
 465
 466         /* Remove the symlink */
 467         sysfs_remove_link(&pci->kobj, EDAC_PCI_SYMLINK);
 468
 469         /* remove this PCI instance's sysfs entries */
 470         edac_pci_unregister_sysfs_instance_kobj(pci);
 471
 472         /* Call the main unregister function, which will determine
 473          * if this 'pci' is the last instance.
 474          * If it is, the main kobject will be unregistered as a result
 475          */
 476         edac_dbg(0, "calling edac_pci_main_kobj_teardown()\n");
 477         edac_pci_main_kobj_teardown();
 478 }
 479
 480 /************************ PCI error handling *************************/
 481 static u16 get_pci_parity_status(struct pci_dev *dev, int secondary)
 482 {
 483         int where;
 484         u16 status;
 485
 486         where = secondary ? PCI_SEC_STATUS : PCI_STATUS;
 487         pci_read_config_word(dev, where, &status);
 488
 489         /* If we get back 0xFFFF then we must suspect that the card has been
 490          * pulled but the Linux PCI layer has not yet finished cleaning up.
 491          * We don't want to report on such devices
 492          */
 493
 494         if (status == 0xFFFF) {
 495                 u32 sanity;
 496
 497                 pci_read_config_dword(dev, 0, &sanity);
 498
 499                 if (sanity == 0xFFFFFFFF)
 500                         return 0;
 501         }
 502
 503         status &= PCI_STATUS_DETECTED_PARITY | PCI_STATUS_SIG_SYSTEM_ERROR |
 504                 PCI_STATUS_PARITY;
 505
 506         if (status)
 507                 /* reset only the bits we are interested in */
 508                 pci_write_config_word(dev, where, status);
 509
 510         return status;
 511 }
 512
 513
 514 /* Clear any PCI parity errors logged by this device. */
 515 static void edac_pci_dev_parity_clear(struct pci_dev *dev)
 516 {
 517         u8 header_type;
 518
 519         get_pci_parity_status(dev, 0);
 520
 521         /* read the device TYPE, looking for bridges */
 522         pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
 523
 524         if ((header_type & PCI_HEADER_TYPE_MASK) == PCI_HEADER_TYPE_BRIDGE)
 525                 get_pci_parity_status(dev, 1);
 526 }
 527
 528 /*
 529  *  PCI Parity polling
 530  *
 531  *      Function to retrieve the current parity status
 532  *      and decode it
 533  *
 534  */
 535 static void edac_pci_dev_parity_test(struct pci_dev *dev)
 536 {
 537         unsigned long flags;
 538         u16 status;
 539         u8 header_type;
 540
 541         /* stop any interrupts until we can acquire the status */
 542         local_irq_save(flags);
 543
 544         /* read the STATUS register on this device */
 545         status = get_pci_parity_status(dev, 0);
 546
 547         /* read the device TYPE, looking for bridges */
 548         pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
 549
 550         local_irq_restore(flags);
 551
 552         edac_dbg(4, "PCI STATUS= 0x%04x %s\n", status, dev_name(&dev->dev));
 553
 554         /* check the status reg for errors on boards NOT marked as broken
 555          * if broken, we cannot trust any of the status bits
 556          */
 557         if (status && !dev->broken_parity_status) {
 558                 if (status & (PCI_STATUS_SIG_SYSTEM_ERROR)) {
 559                         edac_printk(KERN_CRIT, EDAC_PCI,
 560                                 "Signaled System Error on %s\n",
 561                                 pci_name(dev));
 562                         atomic_inc(&pci_nonparity_count);
 563                 }
 564
 565                 if (status & (PCI_STATUS_PARITY)) {
 566                         edac_printk(KERN_CRIT, EDAC_PCI,
 567                                 "Master Data Parity Error on %s\n",
 568                                 pci_name(dev));
 569
 570                         atomic_inc(&pci_parity_count);
 571                 }
 572
 573                 if (status & (PCI_STATUS_DETECTED_PARITY)) {
 574                         edac_printk(KERN_CRIT, EDAC_PCI,
 575                                 "Detected Parity Error on %s\n",
 576                                 pci_name(dev));
 577
 578                         atomic_inc(&pci_parity_count);
 579                 }
 580         }
 581
 582
 583         edac_dbg(4, "PCI HEADER TYPE= 0x%02x %s\n",
 584                  header_type, dev_name(&dev->dev));
 585
 586         if ((header_type & PCI_HEADER_TYPE_MASK) == PCI_HEADER_TYPE_BRIDGE) {
 587                 /* On bridges, need to examine secondary status register  */
 588                 status = get_pci_parity_status(dev, 1);
 589
 590                 edac_dbg(4, "PCI SEC_STATUS= 0x%04x %s\n",
 591                          status, dev_name(&dev->dev));
 592
 593                 /* check the secondary status reg for errors,
 594                  * on NOT broken boards
 595                  */
 596                 if (status && !dev->broken_parity_status) {
 597                         if (status & (PCI_STATUS_SIG_SYSTEM_ERROR)) {
 598                                 edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
 599                                         "Signaled System Error on %s\n",
 600                                         pci_name(dev));
 601                                 atomic_inc(&pci_nonparity_count);
 602                         }
 603
 604                         if (status & (PCI_STATUS_PARITY)) {
 605                                 edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
 606                                         "Master Data Parity Error on "
 607                                         "%s\n", pci_name(dev));
 608
 609                                 atomic_inc(&pci_parity_count);
 610                         }
 611
 612                         if (status & (PCI_STATUS_DETECTED_PARITY)) {
 613                                 edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
 614                                         "Detected Parity Error on %s\n",
 615                                         pci_name(dev));
 616
 617                                 atomic_inc(&pci_parity_count);
 618                         }
 619                 }
 620         }
 621 }
 622
 623 /* reduce some complexity in definition of the iterator */
 624 typedef void (*pci_parity_check_fn_t) (struct pci_dev *dev);
 625
 626 /*
 627  * pci_dev parity list iterator
 628  *
 629  *      Scan the PCI device list looking for SERRORs, Master Parity ERRORS or
 630  *      Parity ERRORs on primary or secondary devices.
 631  */
 632 static inline void edac_pci_dev_parity_iterator(pci_parity_check_fn_t fn)
 633 {
 634         struct pci_dev *dev = NULL;
 635
 636         for_each_pci_dev(dev)
 637                 fn(dev);
 638 }
 639
 640 /*
 641  * edac_pci_do_parity_check
 642  *
 643  *      performs the actual PCI parity check operation
 644  */
 645 void edac_pci_do_parity_check(void)
 646 {
 647         int before_count;
 648
 649         edac_dbg(3, "\n");
 650
 651         /* if policy has PCI check off, leave now */
 652         if (!check_pci_errors)
 653                 return;
 654
 655         before_count = atomic_read(&pci_parity_count);
 656
 657         /* scan all PCI devices looking for a Parity Error on devices and
 658          * bridges.
 659          * The iterator calls pci_get_device() which might sleep, thus
 660          * we cannot disable interrupts in this scan.
 661          */
 662         edac_pci_dev_parity_iterator(edac_pci_dev_parity_test);
 663
 664         /* Only if operator has selected panic on PCI Error */
 665         if (edac_pci_get_panic_on_pe()) {
 666                 /* If the count is different 'after' from 'before' */
 667                 if (before_count != atomic_read(&pci_parity_count))
 668                         panic("EDAC: PCI Parity Error");
 669         }
 670 }
 671
 672 /*
 673  * edac_pci_clear_parity_errors
 674  *
 675  *      function to perform an iteration over the PCI devices
 676  *      and clearn their current status
 677  */
 678 void edac_pci_clear_parity_errors(void)
 679 {
 680         /* Clear any PCI bus parity errors that devices initially have logged
 681          * in their registers.
 682          */
 683         edac_pci_dev_parity_iterator(edac_pci_dev_parity_clear);
 684 }
 685
 686 /*
 687  * edac_pci_handle_pe
 688  *
 689  *      Called to handle a PARITY ERROR event
 690  */
 691 void edac_pci_handle_pe(struct edac_pci_ctl_info *pci, const char *msg)
 692 {
 693
 694         /* global PE counter incremented by edac_pci_do_parity_check() */
 695         atomic_inc(&pci->counters.pe_count);
 696
 697         if (edac_pci_get_log_pe())
 698                 edac_pci_printk(pci, KERN_WARNING,
 699                                 "Parity Error ctl: %s %d: %s\n",
 700                                 pci->ctl_name, pci->pci_idx, msg);
 701
 702         /*
 703          * poke all PCI devices and see which one is the troublemaker
 704          * panic() is called if set
 705          */
 706         edac_pci_do_parity_check();
 707 }
 708 EXPORT_SYMBOL_GPL(edac_pci_handle_pe);
 709
 710
 711 /*
 712  * edac_pci_handle_npe
 713  *
 714  *      Called to handle a NON-PARITY ERROR event
 715  */
 716 void edac_pci_handle_npe(struct edac_pci_ctl_info *pci, const char *msg)
 717 {
 718
 719         /* global NPE counter incremented by edac_pci_do_parity_check() */
 720         atomic_inc(&pci->counters.npe_count);
 721
 722         if (edac_pci_get_log_npe())
 723                 edac_pci_printk(pci, KERN_WARNING,
 724                                 "Non-Parity Error ctl: %s %d: %s\n",
 725                                 pci->ctl_name, pci->pci_idx, msg);
 726
 727         /*
 728          * poke all PCI devices and see which one is the troublemaker
 729          * panic() is called if set
 730          */
 731         edac_pci_do_parity_check();
 732 }
 733 EXPORT_SYMBOL_GPL(edac_pci_handle_npe);
 734
 735 /*
 736  * Define the PCI parameter to the module
 737  */
 738 module_param(check_pci_errors, int, 0644);
 739 MODULE_PARM_DESC(check_pci_errors,
 740                  "Check for PCI bus parity errors: 0=off 1=on");
 741 module_param(edac_pci_panic_on_pe, int, 0644);
 742 MODULE_PARM_DESC(edac_pci_panic_on_pe,
 743                  "Panic on PCI Bus Parity error: 0=off 1=on");