drivers/edac/edac_pci.c

   1 /*
   2  * EDAC PCI component
   3  *
   4  * Author: Dave Jiang <djiang@mvista.com>
   5  *
   6  * 2007 (c) MontaVista Software, Inc. This file is licensed under
   7  * the terms of the GNU General Public License version 2. This program
   8  * is licensed "as is" without any warranty of any kind, whether express
   9  * or implied.
  10  *
  11  */
  12 #include <linux/module.h>
  13 #include <linux/types.h>
  14 #include <linux/smp.h>
  15 #include <linux/init.h>
  16 #include <linux/sysctl.h>
  17 #include <linux/highmem.h>
  18 #include <linux/timer.h>
  19 #include <linux/slab.h>
  20 #include <linux/spinlock.h>
  21 #include <linux/list.h>
  22 #include <linux/sysdev.h>
  23 #include <linux/ctype.h>
  24 #include <linux/workqueue.h>
  25 #include <asm/uaccess.h>
  26 #include <asm/page.h>
  27
  28 #include "edac_core.h"
  29 #include "edac_module.h"
  30
  31 static DEFINE_MUTEX(edac_pci_ctls_mutex);
  32 static struct list_head edac_pci_list = LIST_HEAD_INIT(edac_pci_list);
  33
  34 static inline void edac_lock_pci_list(void)
  35 {
  36         mutex_lock(&edac_pci_ctls_mutex);
  37 }
  38
  39 static inline void edac_unlock_pci_list(void)
  40 {
  41         mutex_unlock(&edac_pci_ctls_mutex);
  42 }
  43
  44 /*
  45  * The alloc() and free() functions for the 'edac_pci' control info
  46  * structure. The chip driver will allocate one of these for each
  47  * edac_pci it is going to control/register with the EDAC CORE.
  48  */
  49 struct edac_pci_ctl_info * edac_pci_alloc_ctl_info(
  50         unsigned int sz_pvt,
  51         const char *edac_pci_name)
  52 {
  53         struct edac_pci_ctl_info *pci;
  54         void *pvt;
  55         unsigned int size;
  56
  57         pci = (struct edac_pci_ctl_info *)0;
  58         pvt = edac_align_ptr(&pci[1], sz_pvt);
  59         size = ((unsigned long)pvt) + sz_pvt;
  60
  61         if ((pci = kzalloc(size, GFP_KERNEL)) == NULL)
  62                 return NULL;
  63
  64         pvt = sz_pvt ? ((char *)pci) + ((unsigned long)pvt) : NULL;
  65
  66         pci->pvt_info = pvt;
  67
  68         pci->op_state = OP_ALLOC;
  69
  70         snprintf(pci->name, strlen(edac_pci_name)+1, "%s", edac_pci_name);
  71
  72         return pci;
  73 }
  74 EXPORT_SYMBOL_GPL(edac_pci_alloc_ctl_info);
  75
  76 /*
  77  * edac_pci_free_ctl_info()
  78  *      frees the memory allocated by edac_pci_alloc_ctl_info() function
  79  */
  80 void edac_pci_free_ctl_info(struct edac_pci_ctl_info *pci)
  81 {
  82         kfree(pci);
  83 }
  84 EXPORT_SYMBOL_GPL(edac_pci_free_ctl_info);
  85
  86 /*
  87  * find_edac_pci_by_dev()
  88  *      scans the edac_pci list for a specific 'struct device *'
  89  */
  90 static struct edac_pci_ctl_info * find_edac_pci_by_dev(struct device *dev)
  91 {
  92         struct edac_pci_ctl_info *pci;
  93         struct list_head *item;
  94
  95         debugf3("%s()\n", __func__);
  96
  97         list_for_each(item, &edac_pci_list) {
  98                 pci = list_entry(item, struct edac_pci_ctl_info, link);
  99
 100                 if (pci->dev == dev)
 101                         return pci;
 102         }
 103
 104         return NULL;
 105 }
 106
 107 /*
 108  * add_edac_pci_to_global_list
 109  *      Before calling this function, caller must assign a unique value to
 110  *      edac_dev->pci_idx.
 111  *      Return:
 112  *              0 on success
 113  *              1 on failure
 114  */
 115 static int add_edac_pci_to_global_list(struct edac_pci_ctl_info *pci)
 116 {
 117         struct list_head *item, *insert_before;
 118         struct edac_pci_ctl_info *rover;
 119
 120         insert_before = &edac_pci_list;
 121
 122         /* Determine if already on the list */
 123         if (unlikely((rover = find_edac_pci_by_dev(pci->dev)) != NULL))
 124                 goto fail0;
 125
 126         /* Insert in ascending order by 'pci_idx', so find position */
 127         list_for_each(item, &edac_pci_list) {
 128                 rover = list_entry(item, struct edac_pci_ctl_info, link);
 129
 130                 if (rover->pci_idx >= pci->pci_idx) {
 131                         if (unlikely(rover->pci_idx == pci->pci_idx))
 132                                 goto fail1;
 133
 134                         insert_before = item;
 135                         break;
 136                 }
 137         }
 138
 139         list_add_tail_rcu(&pci->link, insert_before);
 140         return 0;
 141
 142 fail0:
 143         edac_printk(KERN_WARNING, EDAC_PCI,
 144                 "%s (%s) %s %s already assigned %d\n",
 145                 rover->dev->bus_id, dev_name(rover),
 146                 rover->mod_name, rover->ctl_name, rover->pci_idx);
 147         return 1;
 148
 149 fail1:
 150         edac_printk(KERN_WARNING, EDAC_PCI,
 151                 "but in low-level driver: attempt to assign\n"
 152                 "\tduplicate pci_idx %d in %s()\n", rover->pci_idx, __func__);
 153         return 1;
 154 }
 155
 156 /*
 157  * complete_edac_pci_list_del
 158  */
 159 static void complete_edac_pci_list_del(struct rcu_head *head)
 160 {
 161         struct edac_pci_ctl_info *pci;
 162
 163         pci = container_of(head, struct edac_pci_ctl_info, rcu);
 164         INIT_LIST_HEAD(&pci->link);
 165         complete(&pci->complete);
 166 }
 167
 168 /*
 169  * del_edac_pci_from_global_list
 170  */
 171 static void del_edac_pci_from_global_list(struct edac_pci_ctl_info *pci)
 172 {
 173         list_del_rcu(&pci->link);
 174         init_completion(&pci->complete);
 175         call_rcu(&pci->rcu, complete_edac_pci_list_del);
 176         wait_for_completion(&pci->complete);
 177 }
 178
 179 /*
 180  * edac_pci_find()
 181  *      Search for an edac_pci_ctl_info structure whose index is 'idx'
 182  *
 183  * If found, return a pointer to the structure
 184  * Else return NULL.
 185  *
 186  * Caller must hold pci_ctls_mutex.
 187  */
 188 struct edac_pci_ctl_info * edac_pci_find(int idx)
 189 {
 190         struct list_head *item;
 191         struct edac_pci_ctl_info *pci;
 192
 193         /* Iterage over list, looking for exact match of ID */
 194         list_for_each(item, &edac_pci_list) {
 195                 pci = list_entry(item, struct edac_pci_ctl_info, link);
 196
 197                 if (pci->pci_idx >= idx) {
 198                         if (pci->pci_idx == idx)
 199                                 return pci;
 200
 201                 /* not on list, so terminate early */
 202                         break;
 203                 }
 204         }
 205
 206         return NULL;
 207 }
 208 EXPORT_SYMBOL_GPL(edac_pci_find);
 209
 210 /*
 211  * edac_pci_workq_function()
 212  *      performs the operation scheduled by a workq request
 213  */
 214 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,20))
 215 static void edac_pci_workq_function(struct work_struct *work_req)
 216 {
 217         struct delayed_work *d_work = (struct delayed_work *)work_req;
 218         struct edac_pci_ctl_info *pci = to_edac_pci_ctl_work(d_work);
 219 #else
 220 static void edac_pci_workq_function(void *ptr)
 221 {
 222         struct edac_pci_ctl_info *pci = ptr;
 223 #endif
 224
 225         edac_lock_pci_list();
 226
 227         if ((pci->op_state == OP_RUNNING_POLL) &&
 228                 (pci->edac_check != NULL) &&
 229                 (edac_pci_get_check_errors()))
 230                 pci->edac_check(pci);
 231
 232         edac_unlock_pci_list();
 233
 234         /* Reschedule */
 235         queue_delayed_work(edac_workqueue, &pci->work,
 236                         msecs_to_jiffies(edac_pci_get_poll_msec()));
 237 }
 238
 239 /*
 240  * edac_pci_workq_setup()
 241  *      initialize a workq item for this edac_pci instance
 242  *      passing in the new delay period in msec
 243  */
 244 static void edac_pci_workq_setup(struct edac_pci_ctl_info *pci,
 245                 unsigned int msec)
 246 {
 247         debugf0("%s()\n", __func__);
 248
 249 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,20))
 250         INIT_DELAYED_WORK(&pci->work, edac_pci_workq_function);
 251 #else
 252         INIT_WORK(&pci->work, edac_pci_workq_function, pci);
 253 #endif
 254         queue_delayed_work(edac_workqueue, &pci->work,
 255                         msecs_to_jiffies(edac_pci_get_poll_msec()));
 256 }
 257
 258 /*
 259  * edac_pci_workq_teardown()
 260  *      stop the workq processing on this edac_pci instance
 261  */
 262 static void edac_pci_workq_teardown(struct edac_pci_ctl_info *pci)
 263 {
 264         int status;
 265
 266         status = cancel_delayed_work(&pci->work);
 267         if (status == 0)
 268                 flush_workqueue(edac_workqueue);
 269 }
 270
 271 /*
 272  * edac_pci_reset_delay_period
 273  */
 274 void edac_pci_reset_delay_period(struct edac_pci_ctl_info *pci,
 275                 unsigned long value)
 276 {
 277         edac_lock_pci_list();
 278
 279         edac_pci_workq_teardown(pci);
 280
 281         edac_pci_workq_setup(pci, value);
 282
 283         edac_unlock_pci_list();
 284 }
 285 EXPORT_SYMBOL_GPL(edac_pci_reset_delay_period);
 286
 287 /*
 288  * edac_pci_add_device: Insert the 'edac_dev' structure into the
 289  * edac_pci global list and create sysfs entries associated with
 290  * edac_pci structure.
 291  * @pci: pointer to the edac_device structure to be added to the list
 292  * @edac_idx: A unique numeric identifier to be assigned to the
 293  * 'edac_pci' structure.
 294  *
 295  * Return:
 296  *      0       Success
 297  *      !0      Failure
 298  */
 299 int edac_pci_add_device(struct edac_pci_ctl_info *pci, int edac_idx)
 300 {
 301         debugf0("%s()\n", __func__);
 302
 303         pci->pci_idx = edac_idx;
 304
 305         edac_lock_pci_list();
 306
 307         if (add_edac_pci_to_global_list(pci))
 308                 goto fail0;
 309
 310         pci->start_time = jiffies;
 311
 312         if (edac_pci_create_sysfs(pci)) {
 313                 edac_pci_printk(pci, KERN_WARNING,
 314                                 "failed to create sysfs pci\n");
 315                 goto fail1;
 316         }
 317
 318         if (pci->edac_check != NULL) {
 319                 pci->op_state = OP_RUNNING_POLL;
 320
 321                 edac_pci_workq_setup(pci, 1000);
 322         } else {
 323                 pci->op_state = OP_RUNNING_INTERRUPT;
 324         }
 325
 326         edac_pci_printk(pci, KERN_INFO,
 327                 "Giving out device to module '%s' controller '%s':"
 328                 " DEV '%s' (%s)\n",
 329                 pci->mod_name,
 330                 pci->ctl_name,
 331                 dev_name(pci),
 332                 edac_op_state_toString(pci->op_state));
 333
 334         edac_unlock_pci_list();
 335         return 0;
 336
 337 fail1:
 338         del_edac_pci_from_global_list(pci);
 339 fail0:
 340         edac_unlock_pci_list();
 341         return 1;
 342 }
 343 EXPORT_SYMBOL_GPL(edac_pci_add_device);
 344
 345 /*
 346  * edac_pci_del_device()
 347  *      Remove sysfs entries for specified edac_pci structure and
 348  *      then remove edac_pci structure from global list
 349  *
 350  * @dev:
 351  *      Pointer to 'struct device' representing edac_pci structure
 352  *      to remove
 353  *
 354  * Return:
 355  *      Pointer to removed edac_pci structure,
 356  *      or NULL if device not found
 357  */
 358 struct edac_pci_ctl_info * edac_pci_del_device(struct device *dev)
 359 {
 360         struct edac_pci_ctl_info *pci;
 361
 362         debugf0("%s()\n", __func__);
 363
 364         edac_lock_pci_list();
 365
 366         if ((pci = find_edac_pci_by_dev(dev)) == NULL) {
 367                 edac_unlock_pci_list();
 368                 return NULL;
 369         }
 370
 371         pci->op_state = OP_OFFLINE;
 372
 373         edac_pci_workq_teardown(pci);
 374
 375         edac_pci_remove_sysfs(pci);
 376
 377         del_edac_pci_from_global_list(pci);
 378
 379         edac_unlock_pci_list();
 380
 381         edac_printk(KERN_INFO, EDAC_PCI,
 382                 "Removed device %d for %s %s: DEV %s\n",
 383                 pci->pci_idx,
 384                 pci->mod_name,
 385                 pci->ctl_name,
 386                 dev_name(pci));
 387
 388         return pci;
 389 }
 390 EXPORT_SYMBOL_GPL(edac_pci_del_device);
 391
 392 void edac_pci_generic_check(struct edac_pci_ctl_info *pci)
 393 {
 394         edac_pci_do_parity_check();
 395 }
 396
 397 static int edac_pci_idx = 0;
 398 #define EDAC_PCI_GENCTL_NAME    "EDAC PCI controller"
 399
 400 struct edac_pci_gen_data {
 401         int edac_idx;
 402 };
 403
 404 struct edac_pci_ctl_info *
 405 edac_pci_create_generic_ctl(struct device *dev, const char *mod_name)
 406 {
 407         struct edac_pci_ctl_info *pci;
 408         struct edac_pci_gen_data *pdata;
 409
 410         pci = edac_pci_alloc_ctl_info(sizeof(*pdata), EDAC_PCI_GENCTL_NAME);
 411         if (!pci)
 412                 return NULL;
 413
 414         pdata = pci->pvt_info;
 415         pci->dev = dev;
 416         dev_set_drvdata(pci->dev, pci);
 417         pci->dev_name = pci_name(to_pci_dev(dev));
 418
 419         pci->mod_name = mod_name;
 420         pci->ctl_name = EDAC_PCI_GENCTL_NAME;
 421         pci->edac_check = edac_pci_generic_check;
 422
 423         pdata->edac_idx = edac_pci_idx++;
 424
 425         if (edac_pci_add_device(pci, pdata->edac_idx) > 0) {
 426                 debugf3("%s(): failed edac_pci_add_device()\n", __func__);
 427                 edac_pci_free_ctl_info(pci);
 428                 return NULL;
 429         }
 430
 431         return pci;
 432 }
 433 EXPORT_SYMBOL_GPL(edac_pci_create_generic_ctl);
 434
 435 void edac_pci_release_generic_ctl(struct edac_pci_ctl_info *pci)
 436 {
 437         edac_pci_del_device(pci->dev);
 438         edac_pci_free_ctl_info(pci);
 439 }
 440 EXPORT_SYMBOL_GPL(edac_pci_release_generic_ctl);