drivers/edac/edac_pci.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * EDAC PCI component
   4  *
   5  * Author: Dave Jiang <djiang@mvista.com>
   6  *
   7  * 2007 (c) MontaVista Software, Inc.
   8  */
   9 #include <asm/page.h>
  10 #include <linux/uaccess.h>
  11 #include <linux/ctype.h>
  12 #include <linux/highmem.h>
  13 #include <linux/init.h>
  14 #include <linux/module.h>
  15 #include <linux/slab.h>
  16 #include <linux/smp.h>
  17 #include <linux/spinlock.h>
  18 #include <linux/sysctl.h>
  19 #include <linux/timer.h>
  20
  21 #include "edac_pci.h"
  22 #include "edac_module.h"
  23
  24 static DEFINE_MUTEX(edac_pci_ctls_mutex);
  25 static LIST_HEAD(edac_pci_list);
  26 static atomic_t pci_indexes = ATOMIC_INIT(0);
  27
  28 struct edac_pci_ctl_info *edac_pci_alloc_ctl_info(unsigned int sz_pvt,
  29                                                   const char *edac_pci_name)
  30 {
  31         struct edac_pci_ctl_info *pci;
  32
  33         edac_dbg(1, "\n");
  34
  35         pci = kzalloc(sizeof(struct edac_pci_ctl_info), GFP_KERNEL);
  36         if (!pci)
  37                 return NULL;
  38
  39         if (sz_pvt) {
  40                 pci->pvt_info = kzalloc(sz_pvt, GFP_KERNEL);
  41                 if (!pci->pvt_info)
  42                         goto free;
  43         }
  44
  45         pci->op_state = OP_ALLOC;
  46
  47         snprintf(pci->name, strlen(edac_pci_name) + 1, "%s", edac_pci_name);
  48
  49         return pci;
  50
  51 free:
  52         kfree(pci);
  53         return NULL;
  54 }
  55 EXPORT_SYMBOL_GPL(edac_pci_alloc_ctl_info);
  56
  57 void edac_pci_free_ctl_info(struct edac_pci_ctl_info *pci)
  58 {
  59         edac_dbg(1, "\n");
  60
  61         edac_pci_remove_sysfs(pci);
  62 }
  63 EXPORT_SYMBOL_GPL(edac_pci_free_ctl_info);
  64
  65 /*
  66  * find_edac_pci_by_dev()
  67  *      scans the edac_pci list for a specific 'struct device *'
  68  *
  69  *      return NULL if not found, or return control struct pointer
  70  */
  71 static struct edac_pci_ctl_info *find_edac_pci_by_dev(struct device *dev)
  72 {
  73         struct edac_pci_ctl_info *pci;
  74         struct list_head *item;
  75
  76         edac_dbg(1, "\n");
  77
  78         list_for_each(item, &edac_pci_list) {
  79                 pci = list_entry(item, struct edac_pci_ctl_info, link);
  80
  81                 if (pci->dev == dev)
  82                         return pci;
  83         }
  84
  85         return NULL;
  86 }
  87
  88 /*
  89  * add_edac_pci_to_global_list
  90  *      Before calling this function, caller must assign a unique value to
  91  *      edac_dev->pci_idx.
  92  *      Return:
  93  *              0 on success
  94  *              1 on failure
  95  */
  96 static int add_edac_pci_to_global_list(struct edac_pci_ctl_info *pci)
  97 {
  98         struct list_head *item, *insert_before;
  99         struct edac_pci_ctl_info *rover;
 100
 101         edac_dbg(1, "\n");
 102
 103         insert_before = &edac_pci_list;
 104
 105         /* Determine if already on the list */
 106         rover = find_edac_pci_by_dev(pci->dev);
 107         if (unlikely(rover != NULL))
 108                 goto fail0;
 109
 110         /* Insert in ascending order by 'pci_idx', so find position */
 111         list_for_each(item, &edac_pci_list) {
 112                 rover = list_entry(item, struct edac_pci_ctl_info, link);
 113
 114                 if (rover->pci_idx >= pci->pci_idx) {
 115                         if (unlikely(rover->pci_idx == pci->pci_idx))
 116                                 goto fail1;
 117
 118                         insert_before = item;
 119                         break;
 120                 }
 121         }
 122
 123         list_add_tail_rcu(&pci->link, insert_before);
 124         return 0;
 125
 126 fail0:
 127         edac_printk(KERN_WARNING, EDAC_PCI,
 128                 "%s (%s) %s %s already assigned %d\n",
 129                 dev_name(rover->dev), edac_dev_name(rover),
 130                 rover->mod_name, rover->ctl_name, rover->pci_idx);
 131         return 1;
 132
 133 fail1:
 134         edac_printk(KERN_WARNING, EDAC_PCI,
 135                 "but in low-level driver: attempt to assign\n"
 136                 "\tduplicate pci_idx %d in %s()\n", rover->pci_idx,
 137                 __func__);
 138         return 1;
 139 }
 140
 141 /*
 142  * del_edac_pci_from_global_list
 143  *
 144  *      remove the PCI control struct from the global list
 145  */
 146 static void del_edac_pci_from_global_list(struct edac_pci_ctl_info *pci)
 147 {
 148         list_del_rcu(&pci->link);
 149
 150         /* these are for safe removal of devices from global list while
 151          * NMI handlers may be traversing list
 152          */
 153         synchronize_rcu();
 154         INIT_LIST_HEAD(&pci->link);
 155 }
 156
 157 /*
 158  * edac_pci_workq_function()
 159  *
 160  *      periodic function that performs the operation
 161  *      scheduled by a workq request, for a given PCI control struct
 162  */
 163 static void edac_pci_workq_function(struct work_struct *work_req)
 164 {
 165         struct delayed_work *d_work = to_delayed_work(work_req);
 166         struct edac_pci_ctl_info *pci = to_edac_pci_ctl_work(d_work);
 167         int msec;
 168         unsigned long delay;
 169
 170         edac_dbg(3, "checking\n");
 171
 172         mutex_lock(&edac_pci_ctls_mutex);
 173
 174         if (pci->op_state != OP_RUNNING_POLL) {
 175                 mutex_unlock(&edac_pci_ctls_mutex);
 176                 return;
 177         }
 178
 179         if (edac_pci_get_check_errors())
 180                 pci->edac_check(pci);
 181
 182         /* if we are on a one second period, then use round */
 183         msec = edac_pci_get_poll_msec();
 184         if (msec == 1000)
 185                 delay = round_jiffies_relative(msecs_to_jiffies(msec));
 186         else
 187                 delay = msecs_to_jiffies(msec);
 188
 189         edac_queue_work(&pci->work, delay);
 190
 191         mutex_unlock(&edac_pci_ctls_mutex);
 192 }
 193
 194 int edac_pci_alloc_index(void)
 195 {
 196         return atomic_inc_return(&pci_indexes) - 1;
 197 }
 198 EXPORT_SYMBOL_GPL(edac_pci_alloc_index);
 199
 200 int edac_pci_add_device(struct edac_pci_ctl_info *pci, int edac_idx)
 201 {
 202         edac_dbg(0, "\n");
 203
 204         pci->pci_idx = edac_idx;
 205         pci->start_time = jiffies;
 206
 207         mutex_lock(&edac_pci_ctls_mutex);
 208
 209         if (add_edac_pci_to_global_list(pci))
 210                 goto fail0;
 211
 212         if (edac_pci_create_sysfs(pci)) {
 213                 edac_pci_printk(pci, KERN_WARNING,
 214                                 "failed to create sysfs pci\n");
 215                 goto fail1;
 216         }
 217
 218         if (pci->edac_check) {
 219                 pci->op_state = OP_RUNNING_POLL;
 220
 221                 INIT_DELAYED_WORK(&pci->work, edac_pci_workq_function);
 222                 edac_queue_work(&pci->work, msecs_to_jiffies(edac_pci_get_poll_msec()));
 223
 224         } else {
 225                 pci->op_state = OP_RUNNING_INTERRUPT;
 226         }
 227
 228         edac_pci_printk(pci, KERN_INFO,
 229                 "Giving out device to module %s controller %s: DEV %s (%s)\n",
 230                 pci->mod_name, pci->ctl_name, pci->dev_name,
 231                 edac_op_state_to_string(pci->op_state));
 232
 233         mutex_unlock(&edac_pci_ctls_mutex);
 234         return 0;
 235
 236         /* error unwind stack */
 237 fail1:
 238         del_edac_pci_from_global_list(pci);
 239 fail0:
 240         mutex_unlock(&edac_pci_ctls_mutex);
 241         return 1;
 242 }
 243 EXPORT_SYMBOL_GPL(edac_pci_add_device);
 244
 245 struct edac_pci_ctl_info *edac_pci_del_device(struct device *dev)
 246 {
 247         struct edac_pci_ctl_info *pci;
 248
 249         edac_dbg(0, "\n");
 250
 251         mutex_lock(&edac_pci_ctls_mutex);
 252
 253         /* ensure the control struct is on the global list
 254          * if not, then leave
 255          */
 256         pci = find_edac_pci_by_dev(dev);
 257         if (pci  == NULL) {
 258                 mutex_unlock(&edac_pci_ctls_mutex);
 259                 return NULL;
 260         }
 261
 262         pci->op_state = OP_OFFLINE;
 263
 264         del_edac_pci_from_global_list(pci);
 265
 266         mutex_unlock(&edac_pci_ctls_mutex);
 267
 268         if (pci->edac_check)
 269                 edac_stop_work(&pci->work);
 270
 271         edac_printk(KERN_INFO, EDAC_PCI,
 272                 "Removed device %d for %s %s: DEV %s\n",
 273                 pci->pci_idx, pci->mod_name, pci->ctl_name, edac_dev_name(pci));
 274
 275         return pci;
 276 }
 277 EXPORT_SYMBOL_GPL(edac_pci_del_device);
 278
 279 /*
 280  * edac_pci_generic_check
 281  *
 282  *      a Generic parity check API
 283  */
 284 static void edac_pci_generic_check(struct edac_pci_ctl_info *pci)
 285 {
 286         edac_dbg(4, "\n");
 287         edac_pci_do_parity_check();
 288 }
 289
 290 /* free running instance index counter */
 291 static int edac_pci_idx;
 292 #define EDAC_PCI_GENCTL_NAME    "EDAC PCI controller"
 293
 294 struct edac_pci_gen_data {
 295         int edac_idx;
 296 };
 297
 298 struct edac_pci_ctl_info *edac_pci_create_generic_ctl(struct device *dev,
 299                                                 const char *mod_name)
 300 {
 301         struct edac_pci_ctl_info *pci;
 302         struct edac_pci_gen_data *pdata;
 303
 304         pci = edac_pci_alloc_ctl_info(sizeof(*pdata), EDAC_PCI_GENCTL_NAME);
 305         if (!pci)
 306                 return NULL;
 307
 308         pdata = pci->pvt_info;
 309         pci->dev = dev;
 310         dev_set_drvdata(pci->dev, pci);
 311         pci->dev_name = pci_name(to_pci_dev(dev));
 312
 313         pci->mod_name = mod_name;
 314         pci->ctl_name = EDAC_PCI_GENCTL_NAME;
 315         if (edac_op_state == EDAC_OPSTATE_POLL)
 316                 pci->edac_check = edac_pci_generic_check;
 317
 318         pdata->edac_idx = edac_pci_idx++;
 319
 320         if (edac_pci_add_device(pci, pdata->edac_idx) > 0) {
 321                 edac_dbg(3, "failed edac_pci_add_device()\n");
 322                 edac_pci_free_ctl_info(pci);
 323                 return NULL;
 324         }
 325
 326         return pci;
 327 }
 328 EXPORT_SYMBOL_GPL(edac_pci_create_generic_ctl);
 329
 330 void edac_pci_release_generic_ctl(struct edac_pci_ctl_info *pci)
 331 {
 332         edac_dbg(0, "pci mod=%s\n", pci->mod_name);
 333
 334         edac_pci_del_device(pci->dev);
 335         edac_pci_free_ctl_info(pci);
 336 }
 337 EXPORT_SYMBOL_GPL(edac_pci_release_generic_ctl);