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/sysdev.h>
  11 #include <linux/ctype.h>
  12
  13 #include "edac_core.h"
  14 #include "edac_module.h"
  15
  16 /* Turn off this whole feature if PCI is not configured */
  17 #ifdef CONFIG_PCI
  18
  19 #define EDAC_PCI_SYMLINK        "device"
  20
  21 /* data variables exported via sysfs */
  22 static int check_pci_errors;            /* default NO check PCI parity */
  23 static int edac_pci_panic_on_pe;        /* default NO panic on PCI Parity */
  24 static int edac_pci_log_pe = 1;         /* log PCI parity errors */
  25 static int edac_pci_log_npe = 1;        /* log PCI non-parity error errors */
  26 static int edac_pci_poll_msec = 1000;   /* one second workq period */
  27
  28 static atomic_t pci_parity_count = ATOMIC_INIT(0);
  29 static atomic_t pci_nonparity_count = ATOMIC_INIT(0);
  30
  31 static struct kobject edac_pci_top_main_kobj;
  32 static atomic_t edac_pci_sysfs_refcount = ATOMIC_INIT(0);
  33
  34 /* getter functions for the data variables */
  35 int edac_pci_get_check_errors(void)
  36 {
  37         return check_pci_errors;
  38 }
  39
  40 int edac_pci_get_log_pe(void)
  41 {
  42         return edac_pci_log_pe;
  43 }
  44
  45 int edac_pci_get_log_npe(void)
  46 {
  47         return edac_pci_log_npe;
  48 }
  49
  50 int edac_pci_get_panic_on_pe(void)
  51 {
  52         return edac_pci_panic_on_pe;
  53 }
  54
  55 int edac_pci_get_poll_msec(void)
  56 {
  57         return edac_pci_poll_msec;
  58 }
  59
  60 /**************************** EDAC PCI sysfs instance *******************/
  61 static ssize_t instance_pe_count_show(struct edac_pci_ctl_info *pci, char *data)
  62 {
  63         return sprintf(data, "%u\n", atomic_read(&pci->counters.pe_count));
  64 }
  65
  66 static ssize_t instance_npe_count_show(struct edac_pci_ctl_info *pci,
  67                                 char *data)
  68 {
  69         return sprintf(data, "%u\n", atomic_read(&pci->counters.npe_count));
  70 }
  71
  72 #define to_instance(k) container_of(k, struct edac_pci_ctl_info, kobj)
  73 #define to_instance_attr(a) container_of(a, struct instance_attribute, attr)
  74
  75 /* DEVICE instance kobject release() function */
  76 static void edac_pci_instance_release(struct kobject *kobj)
  77 {
  78         struct edac_pci_ctl_info *pci;
  79
  80         debugf0("%s()\n", __func__);
  81
  82         /* Form pointer to containing struct, the pci control struct */
  83         pci = to_instance(kobj);
  84
  85         /* decrement reference count on top main kobj */
  86         kobject_put(&edac_pci_top_main_kobj);
  87
  88         kfree(pci);     /* Free the control struct */
  89 }
  90
  91 /* instance specific attribute structure */
  92 struct instance_attribute {
  93         struct attribute attr;
  94         ssize_t(*show) (struct edac_pci_ctl_info *, char *);
  95         ssize_t(*store) (struct edac_pci_ctl_info *, const char *, size_t);
  96 };
  97
  98 /* Function to 'show' fields from the edac_pci 'instance' structure */
  99 static ssize_t edac_pci_instance_show(struct kobject *kobj,
 100                                 struct attribute *attr, char *buffer)
 101 {
 102         struct edac_pci_ctl_info *pci = to_instance(kobj);
 103         struct instance_attribute *instance_attr = to_instance_attr(attr);
 104
 105         if (instance_attr->show)
 106                 return instance_attr->show(pci, buffer);
 107         return -EIO;
 108 }
 109
 110 /* Function to 'store' fields into the edac_pci 'instance' structure */
 111 static ssize_t edac_pci_instance_store(struct kobject *kobj,
 112                                 struct attribute *attr,
 113                                 const char *buffer, size_t count)
 114 {
 115         struct edac_pci_ctl_info *pci = to_instance(kobj);
 116         struct instance_attribute *instance_attr = to_instance_attr(attr);
 117
 118         if (instance_attr->store)
 119                 return instance_attr->store(pci, buffer, count);
 120         return -EIO;
 121 }
 122
 123 /* fs_ops table */
 124 static struct sysfs_ops pci_instance_ops = {
 125         .show = edac_pci_instance_show,
 126         .store = edac_pci_instance_store
 127 };
 128
 129 #define INSTANCE_ATTR(_name, _mode, _show, _store)      \
 130 static struct instance_attribute attr_instance_##_name = {      \
 131         .attr   = {.name = __stringify(_name), .mode = _mode }, \
 132         .show   = _show,                                        \
 133         .store  = _store,                                       \
 134 };
 135
 136 INSTANCE_ATTR(pe_count, S_IRUGO, instance_pe_count_show, NULL);
 137 INSTANCE_ATTR(npe_count, S_IRUGO, instance_npe_count_show, NULL);
 138
 139 /* pci instance attributes */
 140 static struct instance_attribute *pci_instance_attr[] = {
 141         &attr_instance_pe_count,
 142         &attr_instance_npe_count,
 143         NULL
 144 };
 145
 146 /* the ktype for a pci instance */
 147 static struct kobj_type ktype_pci_instance = {
 148         .release = edac_pci_instance_release,
 149         .sysfs_ops = &pci_instance_ops,
 150         .default_attrs = (struct attribute **)pci_instance_attr,
 151 };
 152
 153 /*
 154  * edac_pci_create_instance_kobj
 155  *
 156  *      construct one EDAC PCI instance's kobject for use
 157  */
 158 static int edac_pci_create_instance_kobj(struct edac_pci_ctl_info *pci, int idx)
 159 {
 160         struct kobject *main_kobj;
 161         int err;
 162
 163         debugf0("%s()\n", __func__);
 164
 165         /* First bump the ref count on the top main kobj, which will
 166          * track the number of PCI instances we have, and thus nest
 167          * properly on keeping the module loaded
 168          */
 169         main_kobj = kobject_get(&edac_pci_top_main_kobj);
 170         if (!main_kobj) {
 171                 err = -ENODEV;
 172                 goto error_out;
 173         }
 174
 175         /* And now register this new kobject under the main kobj */
 176         err = kobject_init_and_add(&pci->kobj, &ktype_pci_instance,
 177                                    &edac_pci_top_main_kobj, "pci%d", idx);
 178         if (err != 0) {
 179                 debugf2("%s() failed to register instance pci%d\n",
 180                         __func__, idx);
 181                 kobject_put(&edac_pci_top_main_kobj);
 182                 goto error_out;
 183         }
 184
 185         kobject_uevent(&pci->kobj, KOBJ_ADD);
 186         debugf1("%s() Register instance 'pci%d' kobject\n", __func__, idx);
 187
 188         return 0;
 189
 190         /* Error unwind statck */
 191 error_out:
 192         return err;
 193 }
 194
 195 /*
 196  * edac_pci_unregister_sysfs_instance_kobj
 197  *
 198  *      unregister the kobj for the EDAC PCI instance
 199  */
 200 void edac_pci_unregister_sysfs_instance_kobj(struct edac_pci_ctl_info *pci)
 201 {
 202         debugf0("%s()\n", __func__);
 203
 204         /* Unregister the instance kobject and allow its release
 205          * function release the main reference count and then
 206          * kfree the memory
 207          */
 208         kobject_put(&pci->kobj);
 209 }
 210
 211 /***************************** EDAC PCI sysfs root **********************/
 212 #define to_edacpci(k) container_of(k, struct edac_pci_ctl_info, kobj)
 213 #define to_edacpci_attr(a) container_of(a, struct edac_pci_attr, attr)
 214
 215 /* simple show/store functions for attributes */
 216 static ssize_t edac_pci_int_show(void *ptr, char *buffer)
 217 {
 218         int *value = ptr;
 219         return sprintf(buffer, "%d\n", *value);
 220 }
 221
 222 static ssize_t edac_pci_int_store(void *ptr, const char *buffer, size_t count)
 223 {
 224         int *value = ptr;
 225
 226         if (isdigit(*buffer))
 227                 *value = simple_strtoul(buffer, NULL, 0);
 228
 229         return count;
 230 }
 231
 232 struct edac_pci_dev_attribute {
 233         struct attribute attr;
 234         void *value;
 235          ssize_t(*show) (void *, char *);
 236          ssize_t(*store) (void *, const char *, size_t);
 237 };
 238
 239 /* Set of show/store abstract level functions for PCI Parity object */
 240 static ssize_t edac_pci_dev_show(struct kobject *kobj, struct attribute *attr,
 241                                  char *buffer)
 242 {
 243         struct edac_pci_dev_attribute *edac_pci_dev;
 244         edac_pci_dev = (struct edac_pci_dev_attribute *)attr;
 245
 246         if (edac_pci_dev->show)
 247                 return edac_pci_dev->show(edac_pci_dev->value, buffer);
 248         return -EIO;
 249 }
 250
 251 static ssize_t edac_pci_dev_store(struct kobject *kobj,
 252                                 struct attribute *attr, const char *buffer,
 253                                 size_t count)
 254 {
 255         struct edac_pci_dev_attribute *edac_pci_dev;
 256         edac_pci_dev = (struct edac_pci_dev_attribute *)attr;
 257
 258         if (edac_pci_dev->show)
 259                 return edac_pci_dev->store(edac_pci_dev->value, buffer, count);
 260         return -EIO;
 261 }
 262
 263 static struct sysfs_ops edac_pci_sysfs_ops = {
 264         .show = edac_pci_dev_show,
 265         .store = edac_pci_dev_store
 266 };
 267
 268 #define EDAC_PCI_ATTR(_name,_mode,_show,_store)                 \
 269 static struct edac_pci_dev_attribute edac_pci_attr_##_name = {          \
 270         .attr = {.name = __stringify(_name), .mode = _mode },   \
 271         .value  = &_name,                                       \
 272         .show   = _show,                                        \
 273         .store  = _store,                                       \
 274 };
 275
 276 #define EDAC_PCI_STRING_ATTR(_name,_data,_mode,_show,_store)    \
 277 static struct edac_pci_dev_attribute edac_pci_attr_##_name = {          \
 278         .attr = {.name = __stringify(_name), .mode = _mode },   \
 279         .value  = _data,                                        \
 280         .show   = _show,                                        \
 281         .store  = _store,                                       \
 282 };
 283
 284 /* PCI Parity control files */
 285 EDAC_PCI_ATTR(check_pci_errors, S_IRUGO | S_IWUSR, edac_pci_int_show,
 286         edac_pci_int_store);
 287 EDAC_PCI_ATTR(edac_pci_log_pe, S_IRUGO | S_IWUSR, edac_pci_int_show,
 288         edac_pci_int_store);
 289 EDAC_PCI_ATTR(edac_pci_log_npe, S_IRUGO | S_IWUSR, edac_pci_int_show,
 290         edac_pci_int_store);
 291 EDAC_PCI_ATTR(edac_pci_panic_on_pe, S_IRUGO | S_IWUSR, edac_pci_int_show,
 292         edac_pci_int_store);
 293 EDAC_PCI_ATTR(pci_parity_count, S_IRUGO, edac_pci_int_show, NULL);
 294 EDAC_PCI_ATTR(pci_nonparity_count, S_IRUGO, edac_pci_int_show, NULL);
 295
 296 /* Base Attributes of the memory ECC object */
 297 static struct edac_pci_dev_attribute *edac_pci_attr[] = {
 298         &edac_pci_attr_check_pci_errors,
 299         &edac_pci_attr_edac_pci_log_pe,
 300         &edac_pci_attr_edac_pci_log_npe,
 301         &edac_pci_attr_edac_pci_panic_on_pe,
 302         &edac_pci_attr_pci_parity_count,
 303         &edac_pci_attr_pci_nonparity_count,
 304         NULL,
 305 };
 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
 319         debugf0("%s() here to module_put(THIS_MODULE)\n", __func__);
 320
 321         /* last reference to top EDAC PCI kobject has been removed,
 322          * NOW release our ref count on the core module
 323          */
 324         module_put(THIS_MODULE);
 325 }
 326
 327 /* ktype struct for the EDAC PCI main kobj */
 328 static struct kobj_type ktype_edac_pci_main_kobj = {
 329         .release = edac_pci_release_main_kobj,
 330         .sysfs_ops = &edac_pci_sysfs_ops,
 331         .default_attrs = (struct attribute **)edac_pci_attr,
 332 };
 333
 334 /**
 335  * edac_pci_main_kobj_setup()
 336  *
 337  *      setup the sysfs for EDAC PCI attributes
 338  *      assumes edac_class has already been initialized
 339  */
 340 int edac_pci_main_kobj_setup(void)
 341 {
 342         int err;
 343         struct sysdev_class *edac_class;
 344
 345         debugf0("%s()\n", __func__);
 346
 347         /* check and count if we have already created the main kobject */
 348         if (atomic_inc_return(&edac_pci_sysfs_refcount) != 1)
 349                 return 0;
 350
 351         /* First time, so create the main kobject and its
 352          * controls and atributes
 353          */
 354         edac_class = edac_get_edac_class();
 355         if (edac_class == NULL) {
 356                 debugf1("%s() no edac_class\n", __func__);
 357                 err = -ENODEV;
 358                 goto decrement_count_fail;
 359         }
 360
 361         /* Bump the reference count on this module to ensure the
 362          * modules isn't unloaded until we deconstruct the top
 363          * level main kobj for EDAC PCI
 364          */
 365         if (!try_module_get(THIS_MODULE)) {
 366                 debugf1("%s() try_module_get() failed\n", __func__);
 367                 err = -ENODEV;
 368                 goto decrement_count_fail;
 369         }
 370
 371         /* Instanstiate the pci object */
 372         err = kobject_init_and_add(&edac_pci_top_main_kobj, &ktype_edac_pci_main_kobj,
 373                                    &edac_class->kset.kobj, "pci");
 374         if (err) {
 375                 debugf1("Failed to register '.../edac/pci'\n");
 376                 goto kobject_init_and_add_fail;
 377         }
 378
 379         /* At this point, to 'release' the top level kobject
 380          * for EDAC PCI, then edac_pci_main_kobj_teardown()
 381          * must be used, for resources to be cleaned up properly
 382          */
 383         kobject_uevent(&edac_pci_top_main_kobj, KOBJ_ADD);
 384         debugf1("Registered '.../edac/pci' kobject\n");
 385
 386         return 0;
 387
 388         /* Error unwind statck */
 389 kobject_init_and_add_fail:
 390         module_put(THIS_MODULE);
 391
 392 decrement_count_fail:
 393         /* if are on this error exit, nothing to tear down */
 394         atomic_dec(&edac_pci_sysfs_refcount);
 395
 396         return err;
 397 }
 398
 399 /*
 400  * edac_pci_main_kobj_teardown()
 401  *
 402  *      if no longer linked (needed) remove the top level EDAC PCI
 403  *      kobject with its controls and attributes
 404  */
 405 static void edac_pci_main_kobj_teardown(void)
 406 {
 407         debugf0("%s()\n", __func__);
 408
 409         /* Decrement the count and only if no more controller instances
 410          * are connected perform the unregisteration of the top level
 411          * main kobj
 412          */
 413         if (atomic_dec_return(&edac_pci_sysfs_refcount) == 0) {
 414                 debugf0("%s() called kobject_put on main kobj\n",
 415                         __func__);
 416                 kobject_put(&edac_pci_top_main_kobj);
 417         }
 418 }
 419
 420 /*
 421  *
 422  * edac_pci_create_sysfs
 423  *
 424  *      Create the controls/attributes for the specified EDAC PCI device
 425  */
 426 int edac_pci_create_sysfs(struct edac_pci_ctl_info *pci)
 427 {
 428         int err;
 429         struct kobject *edac_kobj = &pci->kobj;
 430
 431         debugf0("%s() idx=%d\n", __func__, pci->pci_idx);
 432
 433         /* create the top main EDAC PCI kobject, IF needed */
 434         err = edac_pci_main_kobj_setup();
 435         if (err)
 436                 return err;
 437
 438         /* Create this instance's kobject under the MAIN kobject */
 439         err = edac_pci_create_instance_kobj(pci, pci->pci_idx);
 440         if (err)
 441                 goto unregister_cleanup;
 442
 443         err = sysfs_create_link(edac_kobj, &pci->dev->kobj, EDAC_PCI_SYMLINK);
 444         if (err) {
 445                 debugf0("%s() sysfs_create_link() returned err= %d\n",
 446                         __func__, 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 /*
 463  * edac_pci_remove_sysfs
 464  *
 465  *      remove the controls and attributes for this EDAC PCI device
 466  */
 467 void edac_pci_remove_sysfs(struct edac_pci_ctl_info *pci)
 468 {
 469         debugf0("%s() index=%d\n", __func__, pci->pci_idx);
 470
 471         /* Remove the symlink */
 472         sysfs_remove_link(&pci->kobj, EDAC_PCI_SYMLINK);
 473
 474         /* remove this PCI instance's sysfs entries */
 475         edac_pci_unregister_sysfs_instance_kobj(pci);
 476
 477         /* Call the main unregister function, which will determine
 478          * if this 'pci' is the last instance.
 479          * If it is, the main kobject will be unregistered as a result
 480          */
 481         debugf0("%s() calling edac_pci_main_kobj_teardown()\n", __func__);
 482         edac_pci_main_kobj_teardown();
 483 }
 484
 485 /************************ PCI error handling *************************/
 486 static u16 get_pci_parity_status(struct pci_dev *dev, int secondary)
 487 {
 488         int where;
 489         u16 status;
 490
 491         where = secondary ? PCI_SEC_STATUS : PCI_STATUS;
 492         pci_read_config_word(dev, where, &status);
 493
 494         /* If we get back 0xFFFF then we must suspect that the card has been
 495          * pulled but the Linux PCI layer has not yet finished cleaning up.
 496          * We don't want to report on such devices
 497          */
 498
 499         if (status == 0xFFFF) {
 500                 u32 sanity;
 501
 502                 pci_read_config_dword(dev, 0, &sanity);
 503
 504                 if (sanity == 0xFFFFFFFF)
 505                         return 0;
 506         }
 507
 508         status &= PCI_STATUS_DETECTED_PARITY | PCI_STATUS_SIG_SYSTEM_ERROR |
 509                 PCI_STATUS_PARITY;
 510
 511         if (status)
 512                 /* reset only the bits we are interested in */
 513                 pci_write_config_word(dev, where, status);
 514
 515         return status;
 516 }
 517
 518
 519 /* Clear any PCI parity errors logged by this device. */
 520 static void edac_pci_dev_parity_clear(struct pci_dev *dev)
 521 {
 522         u8 header_type;
 523
 524         debugf0("%s()\n", __func__);
 525
 526         get_pci_parity_status(dev, 0);
 527
 528         /* read the device TYPE, looking for bridges */
 529         pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
 530
 531         if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE)
 532                 get_pci_parity_status(dev, 1);
 533 }
 534
 535 /*
 536  *  PCI Parity polling
 537  *
 538  *      Fucntion to retrieve the current parity status
 539  *      and decode it
 540  *
 541  */
 542 static void edac_pci_dev_parity_test(struct pci_dev *dev)
 543 {
 544         unsigned long flags;
 545         u16 status;
 546         u8 header_type;
 547
 548         /* stop any interrupts until we can acquire the status */
 549         local_irq_save(flags);
 550
 551         /* read the STATUS register on this device */
 552         status = get_pci_parity_status(dev, 0);
 553
 554         /* read the device TYPE, looking for bridges */
 555         pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
 556
 557         local_irq_restore(flags);
 558
 559         debugf4("PCI STATUS= 0x%04x %s\n", status, dev->dev.bus_id);
 560
 561         /* check the status reg for errors */
 562         if (status) {
 563                 if (status & (PCI_STATUS_SIG_SYSTEM_ERROR)) {
 564                         edac_printk(KERN_CRIT, EDAC_PCI,
 565                                 "Signaled System Error on %s\n",
 566                                 pci_name(dev));
 567                         atomic_inc(&pci_nonparity_count);
 568                 }
 569
 570                 if (status & (PCI_STATUS_PARITY)) {
 571                         edac_printk(KERN_CRIT, EDAC_PCI,
 572                                 "Master Data Parity Error on %s\n",
 573                                 pci_name(dev));
 574
 575                         atomic_inc(&pci_parity_count);
 576                 }
 577
 578                 if (status & (PCI_STATUS_DETECTED_PARITY)) {
 579                         edac_printk(KERN_CRIT, EDAC_PCI,
 580                                 "Detected Parity Error on %s\n",
 581                                 pci_name(dev));
 582
 583                         atomic_inc(&pci_parity_count);
 584                 }
 585         }
 586
 587
 588         debugf4("PCI HEADER TYPE= 0x%02x %s\n", header_type, dev->dev.bus_id);
 589
 590         if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE) {
 591                 /* On bridges, need to examine secondary status register  */
 592                 status = get_pci_parity_status(dev, 1);
 593
 594                 debugf4("PCI SEC_STATUS= 0x%04x %s\n", status, dev->dev.bus_id);
 595
 596                 /* check the secondary status reg for errors */
 597                 if (status) {
 598                         if (status & (PCI_STATUS_SIG_SYSTEM_ERROR)) {
 599                                 edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
 600                                         "Signaled System Error on %s\n",
 601                                         pci_name(dev));
 602                                 atomic_inc(&pci_nonparity_count);
 603                         }
 604
 605                         if (status & (PCI_STATUS_PARITY)) {
 606                                 edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
 607                                         "Master Data Parity Error on "
 608                                         "%s\n", pci_name(dev));
 609
 610                                 atomic_inc(&pci_parity_count);
 611                         }
 612
 613                         if (status & (PCI_STATUS_DETECTED_PARITY)) {
 614                                 edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
 615                                         "Detected Parity Error on %s\n",
 616                                         pci_name(dev));
 617
 618                                 atomic_inc(&pci_parity_count);
 619                         }
 620                 }
 621         }
 622 }
 623
 624 /* reduce some complexity in definition of the iterator */
 625 typedef void (*pci_parity_check_fn_t) (struct pci_dev *dev);
 626
 627 /*
 628  * pci_dev parity list iterator
 629  *      Scan the PCI device list for one pass, looking for SERRORs
 630  *      Master Parity ERRORS or 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         /* request for kernel access to the next PCI device, if any,
 637          * and while we are looking at it have its reference count
 638          * bumped until we are done with it
 639          */
 640         while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
 641                 fn(dev);
 642         }
 643 }
 644
 645 /*
 646  * edac_pci_do_parity_check
 647  *
 648  *      performs the actual PCI parity check operation
 649  */
 650 void edac_pci_do_parity_check(void)
 651 {
 652         int before_count;
 653
 654         debugf3("%s()\n", __func__);
 655
 656         /* if policy has PCI check off, leave now */
 657         if (!check_pci_errors)
 658                 return;
 659
 660         before_count = atomic_read(&pci_parity_count);
 661
 662         /* scan all PCI devices looking for a Parity Error on devices and
 663          * bridges.
 664          * The iterator calls pci_get_device() which might sleep, thus
 665          * we cannot disable interrupts in this scan.
 666          */
 667         edac_pci_dev_parity_iterator(edac_pci_dev_parity_test);
 668
 669         /* Only if operator has selected panic on PCI Error */
 670         if (edac_pci_get_panic_on_pe()) {
 671                 /* If the count is different 'after' from 'before' */
 672                 if (before_count != atomic_read(&pci_parity_count))
 673                         panic("EDAC: PCI Parity Error");
 674         }
 675 }
 676
 677 /*
 678  * edac_pci_clear_parity_errors
 679  *
 680  *      function to perform an iteration over the PCI devices
 681  *      and clearn their current status
 682  */
 683 void edac_pci_clear_parity_errors(void)
 684 {
 685         /* Clear any PCI bus parity errors that devices initially have logged
 686          * in their registers.
 687          */
 688         edac_pci_dev_parity_iterator(edac_pci_dev_parity_clear);
 689 }
 690
 691 /*
 692  * edac_pci_handle_pe
 693  *
 694  *      Called to handle a PARITY ERROR event
 695  */
 696 void edac_pci_handle_pe(struct edac_pci_ctl_info *pci, const char *msg)
 697 {
 698
 699         /* global PE counter incremented by edac_pci_do_parity_check() */
 700         atomic_inc(&pci->counters.pe_count);
 701
 702         if (edac_pci_get_log_pe())
 703                 edac_pci_printk(pci, KERN_WARNING,
 704                                 "Parity Error ctl: %s %d: %s\n",
 705                                 pci->ctl_name, pci->pci_idx, msg);
 706
 707         /*
 708          * poke all PCI devices and see which one is the troublemaker
 709          * panic() is called if set
 710          */
 711         edac_pci_do_parity_check();
 712 }
 713 EXPORT_SYMBOL_GPL(edac_pci_handle_pe);
 714
 715
 716 /*
 717  * edac_pci_handle_npe
 718  *
 719  *      Called to handle a NON-PARITY ERROR event
 720  */
 721 void edac_pci_handle_npe(struct edac_pci_ctl_info *pci, const char *msg)
 722 {
 723
 724         /* global NPE counter incremented by edac_pci_do_parity_check() */
 725         atomic_inc(&pci->counters.npe_count);
 726
 727         if (edac_pci_get_log_npe())
 728                 edac_pci_printk(pci, KERN_WARNING,
 729                                 "Non-Parity Error ctl: %s %d: %s\n",
 730                                 pci->ctl_name, pci->pci_idx, msg);
 731
 732         /*
 733          * poke all PCI devices and see which one is the troublemaker
 734          * panic() is called if set
 735          */
 736         edac_pci_do_parity_check();
 737 }
 738 EXPORT_SYMBOL_GPL(edac_pci_handle_npe);
 739
 740 /*
 741  * Define the PCI parameter to the module
 742  */
 743 module_param(check_pci_errors, int, 0644);
 744 MODULE_PARM_DESC(check_pci_errors,
 745                  "Check for PCI bus parity errors: 0=off 1=on");
 746 module_param(edac_pci_panic_on_pe, int, 0644);
 747 MODULE_PARM_DESC(edac_pci_panic_on_pe,
 748                  "Panic on PCI Bus Parity error: 0=off 1=on");
 749
 750 #endif                          /* CONFIG_PCI */