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 */
edac_pci_get_check_errors(void)33 int edac_pci_get_check_errors(void)
34 {
35 	return check_pci_errors;
36 }
37 
edac_pci_get_log_pe(void)38 static int edac_pci_get_log_pe(void)
39 {
40 	return edac_pci_log_pe;
41 }
42 
edac_pci_get_log_npe(void)43 static int edac_pci_get_log_npe(void)
44 {
45 	return edac_pci_log_npe;
46 }
47 
edac_pci_get_panic_on_pe(void)48 static int edac_pci_get_panic_on_pe(void)
49 {
50 	return edac_pci_panic_on_pe;
51 }
52 
edac_pci_get_poll_msec(void)53 int edac_pci_get_poll_msec(void)
54 {
55 	return edac_pci_poll_msec;
56 }
57 
58 /**************************** EDAC PCI sysfs instance *******************/
instance_pe_count_show(struct edac_pci_ctl_info * pci,char * data)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 
instance_npe_count_show(struct edac_pci_ctl_info * pci,char * data)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 */
edac_pci_instance_release(struct kobject * kobj)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 */
edac_pci_instance_show(struct kobject * kobj,struct attribute * attr,char * buffer)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 */
edac_pci_instance_store(struct kobject * kobj,struct attribute * attr,const char * buffer,size_t count)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 instance_attribute *pci_instance_attr[] = {
139 	&attr_instance_pe_count,
140 	&attr_instance_npe_count,
141 	NULL
142 };
143 
144 /* the ktype for a pci instance */
145 static struct kobj_type ktype_pci_instance = {
146 	.release = edac_pci_instance_release,
147 	.sysfs_ops = &pci_instance_ops,
148 	.default_attrs = (struct attribute **)pci_instance_attr,
149 };
150 
151 /*
152  * edac_pci_create_instance_kobj
153  *
154  *	construct one EDAC PCI instance's kobject for use
155  */
edac_pci_create_instance_kobj(struct edac_pci_ctl_info * pci,int idx)156 static int edac_pci_create_instance_kobj(struct edac_pci_ctl_info *pci, int idx)
157 {
158 	struct kobject *main_kobj;
159 	int err;
160 
161 	edac_dbg(0, "\n");
162 
163 	/* First bump the ref count on the top main kobj, which will
164 	 * track the number of PCI instances we have, and thus nest
165 	 * properly on keeping the module loaded
166 	 */
167 	main_kobj = kobject_get(edac_pci_top_main_kobj);
168 	if (!main_kobj) {
169 		err = -ENODEV;
170 		goto error_out;
171 	}
172 
173 	/* And now register this new kobject under the main kobj */
174 	err = kobject_init_and_add(&pci->kobj, &ktype_pci_instance,
175 				   edac_pci_top_main_kobj, "pci%d", idx);
176 	if (err != 0) {
177 		edac_dbg(2, "failed to register instance pci%d\n", idx);
178 		kobject_put(edac_pci_top_main_kobj);
179 		goto error_out;
180 	}
181 
182 	kobject_uevent(&pci->kobj, KOBJ_ADD);
183 	edac_dbg(1, "Register instance 'pci%d' kobject\n", idx);
184 
185 	return 0;
186 
187 	/* Error unwind statck */
188 error_out:
189 	return err;
190 }
191 
192 /*
193  * edac_pci_unregister_sysfs_instance_kobj
194  *
195  *	unregister the kobj for the EDAC PCI instance
196  */
edac_pci_unregister_sysfs_instance_kobj(struct edac_pci_ctl_info * pci)197 static void edac_pci_unregister_sysfs_instance_kobj(
198 			struct edac_pci_ctl_info *pci)
199 {
200 	edac_dbg(0, "\n");
201 
202 	/* Unregister the instance kobject and allow its release
203 	 * function release the main reference count and then
204 	 * kfree the memory
205 	 */
206 	kobject_put(&pci->kobj);
207 }
208 
209 /***************************** EDAC PCI sysfs root **********************/
210 #define to_edacpci(k) container_of(k, struct edac_pci_ctl_info, kobj)
211 #define to_edacpci_attr(a) container_of(a, struct edac_pci_attr, attr)
212 
213 /* simple show/store functions for attributes */
edac_pci_int_show(void * ptr,char * buffer)214 static ssize_t edac_pci_int_show(void *ptr, char *buffer)
215 {
216 	int *value = ptr;
217 	return sprintf(buffer, "%d\n", *value);
218 }
219 
edac_pci_int_store(void * ptr,const char * buffer,size_t count)220 static ssize_t edac_pci_int_store(void *ptr, const char *buffer, size_t count)
221 {
222 	int *value = ptr;
223 
224 	if (isdigit(*buffer))
225 		*value = simple_strtoul(buffer, NULL, 0);
226 
227 	return count;
228 }
229 
230 struct edac_pci_dev_attribute {
231 	struct attribute attr;
232 	void *value;
233 	 ssize_t(*show) (void *, char *);
234 	 ssize_t(*store) (void *, const char *, size_t);
235 };
236 
237 /* Set of show/store abstract level functions for PCI Parity object */
edac_pci_dev_show(struct kobject * kobj,struct attribute * attr,char * buffer)238 static ssize_t edac_pci_dev_show(struct kobject *kobj, struct attribute *attr,
239 				 char *buffer)
240 {
241 	struct edac_pci_dev_attribute *edac_pci_dev;
242 	edac_pci_dev = (struct edac_pci_dev_attribute *)attr;
243 
244 	if (edac_pci_dev->show)
245 		return edac_pci_dev->show(edac_pci_dev->value, buffer);
246 	return -EIO;
247 }
248 
edac_pci_dev_store(struct kobject * kobj,struct attribute * attr,const char * buffer,size_t count)249 static ssize_t edac_pci_dev_store(struct kobject *kobj,
250 				struct attribute *attr, const char *buffer,
251 				size_t count)
252 {
253 	struct edac_pci_dev_attribute *edac_pci_dev;
254 	edac_pci_dev = (struct edac_pci_dev_attribute *)attr;
255 
256 	if (edac_pci_dev->store)
257 		return edac_pci_dev->store(edac_pci_dev->value, buffer, count);
258 	return -EIO;
259 }
260 
261 static const struct sysfs_ops edac_pci_sysfs_ops = {
262 	.show = edac_pci_dev_show,
263 	.store = edac_pci_dev_store
264 };
265 
266 #define EDAC_PCI_ATTR(_name,_mode,_show,_store)			\
267 static struct edac_pci_dev_attribute edac_pci_attr_##_name = {		\
268 	.attr = {.name = __stringify(_name), .mode = _mode },	\
269 	.value  = &_name,					\
270 	.show   = _show,					\
271 	.store  = _store,					\
272 };
273 
274 #define EDAC_PCI_STRING_ATTR(_name,_data,_mode,_show,_store)	\
275 static struct edac_pci_dev_attribute edac_pci_attr_##_name = {		\
276 	.attr = {.name = __stringify(_name), .mode = _mode },	\
277 	.value  = _data,					\
278 	.show   = _show,					\
279 	.store  = _store,					\
280 };
281 
282 /* PCI Parity control files */
283 EDAC_PCI_ATTR(check_pci_errors, S_IRUGO | S_IWUSR, edac_pci_int_show,
284 	edac_pci_int_store);
285 EDAC_PCI_ATTR(edac_pci_log_pe, S_IRUGO | S_IWUSR, edac_pci_int_show,
286 	edac_pci_int_store);
287 EDAC_PCI_ATTR(edac_pci_log_npe, S_IRUGO | S_IWUSR, edac_pci_int_show,
288 	edac_pci_int_store);
289 EDAC_PCI_ATTR(edac_pci_panic_on_pe, S_IRUGO | S_IWUSR, edac_pci_int_show,
290 	edac_pci_int_store);
291 EDAC_PCI_ATTR(pci_parity_count, S_IRUGO, edac_pci_int_show, NULL);
292 EDAC_PCI_ATTR(pci_nonparity_count, S_IRUGO, edac_pci_int_show, NULL);
293 
294 /* Base Attributes of the memory ECC object */
295 static struct edac_pci_dev_attribute *edac_pci_attr[] = {
296 	&edac_pci_attr_check_pci_errors,
297 	&edac_pci_attr_edac_pci_log_pe,
298 	&edac_pci_attr_edac_pci_log_npe,
299 	&edac_pci_attr_edac_pci_panic_on_pe,
300 	&edac_pci_attr_pci_parity_count,
301 	&edac_pci_attr_pci_nonparity_count,
302 	NULL,
303 };
304 
305 /*
306  * edac_pci_release_main_kobj
307  *
308  *	This release function is called when the reference count to the
309  *	passed kobj goes to zero.
310  *
311  *	This kobj is the 'main' kobject that EDAC PCI instances
312  *	link to, and thus provide for proper nesting counts
313  */
edac_pci_release_main_kobj(struct kobject * kobj)314 static void edac_pci_release_main_kobj(struct kobject *kobj)
315 {
316 	edac_dbg(0, "here to module_put(THIS_MODULE)\n");
317 
318 	kfree(kobj);
319 
320 	/* last reference to top EDAC PCI kobject has been removed,
321 	 * NOW release our ref count on the core module
322 	 */
323 	module_put(THIS_MODULE);
324 }
325 
326 /* ktype struct for the EDAC PCI main kobj */
327 static struct kobj_type ktype_edac_pci_main_kobj = {
328 	.release = edac_pci_release_main_kobj,
329 	.sysfs_ops = &edac_pci_sysfs_ops,
330 	.default_attrs = (struct attribute **)edac_pci_attr,
331 };
332 
333 /**
334  * edac_pci_main_kobj_setup: Setup the sysfs for EDAC PCI attributes.
335  */
edac_pci_main_kobj_setup(void)336 static int edac_pci_main_kobj_setup(void)
337 {
338 	int err;
339 	struct bus_type *edac_subsys;
340 
341 	edac_dbg(0, "\n");
342 
343 	/* check and count if we have already created the main kobject */
344 	if (atomic_inc_return(&edac_pci_sysfs_refcount) != 1)
345 		return 0;
346 
347 	/* First time, so create the main kobject and its
348 	 * controls and attributes
349 	 */
350 	edac_subsys = edac_get_sysfs_subsys();
351 
352 	/* Bump the reference count on this module to ensure the
353 	 * modules isn't unloaded until we deconstruct the top
354 	 * level main kobj for EDAC PCI
355 	 */
356 	if (!try_module_get(THIS_MODULE)) {
357 		edac_dbg(1, "try_module_get() failed\n");
358 		err = -ENODEV;
359 		goto decrement_count_fail;
360 	}
361 
362 	edac_pci_top_main_kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
363 	if (!edac_pci_top_main_kobj) {
364 		edac_dbg(1, "Failed to allocate\n");
365 		err = -ENOMEM;
366 		goto kzalloc_fail;
367 	}
368 
369 	/* Instanstiate the pci object */
370 	err = kobject_init_and_add(edac_pci_top_main_kobj,
371 				   &ktype_edac_pci_main_kobj,
372 				   &edac_subsys->dev_root->kobj, "pci");
373 	if (err) {
374 		edac_dbg(1, "Failed to register '.../edac/pci'\n");
375 		goto kobject_init_and_add_fail;
376 	}
377 
378 	/* At this point, to 'release' the top level kobject
379 	 * for EDAC PCI, then edac_pci_main_kobj_teardown()
380 	 * must be used, for resources to be cleaned up properly
381 	 */
382 	kobject_uevent(edac_pci_top_main_kobj, KOBJ_ADD);
383 	edac_dbg(1, "Registered '.../edac/pci' kobject\n");
384 
385 	return 0;
386 
387 	/* Error unwind statck */
388 kobject_init_and_add_fail:
389 	kobject_put(edac_pci_top_main_kobj);
390 
391 kzalloc_fail:
392 	module_put(THIS_MODULE);
393 
394 decrement_count_fail:
395 	/* if are on this error exit, nothing to tear down */
396 	atomic_dec(&edac_pci_sysfs_refcount);
397 
398 	return err;
399 }
400 
401 /*
402  * edac_pci_main_kobj_teardown()
403  *
404  *	if no longer linked (needed) remove the top level EDAC PCI
405  *	kobject with its controls and attributes
406  */
edac_pci_main_kobj_teardown(void)407 static void edac_pci_main_kobj_teardown(void)
408 {
409 	edac_dbg(0, "\n");
410 
411 	/* Decrement the count and only if no more controller instances
412 	 * are connected perform the unregisteration of the top level
413 	 * main kobj
414 	 */
415 	if (atomic_dec_return(&edac_pci_sysfs_refcount) == 0) {
416 		edac_dbg(0, "called kobject_put on main kobj\n");
417 		kobject_put(edac_pci_top_main_kobj);
418 	}
419 }
420 
edac_pci_create_sysfs(struct edac_pci_ctl_info * pci)421 int edac_pci_create_sysfs(struct edac_pci_ctl_info *pci)
422 {
423 	int err;
424 	struct kobject *edac_kobj = &pci->kobj;
425 
426 	edac_dbg(0, "idx=%d\n", pci->pci_idx);
427 
428 	/* create the top main EDAC PCI kobject, IF needed */
429 	err = edac_pci_main_kobj_setup();
430 	if (err)
431 		return err;
432 
433 	/* Create this instance's kobject under the MAIN kobject */
434 	err = edac_pci_create_instance_kobj(pci, pci->pci_idx);
435 	if (err)
436 		goto unregister_cleanup;
437 
438 	err = sysfs_create_link(edac_kobj, &pci->dev->kobj, EDAC_PCI_SYMLINK);
439 	if (err) {
440 		edac_dbg(0, "sysfs_create_link() returned err= %d\n", err);
441 		goto symlink_fail;
442 	}
443 
444 	return 0;
445 
446 	/* Error unwind stack */
447 symlink_fail:
448 	edac_pci_unregister_sysfs_instance_kobj(pci);
449 
450 unregister_cleanup:
451 	edac_pci_main_kobj_teardown();
452 
453 	return err;
454 }
455 
edac_pci_remove_sysfs(struct edac_pci_ctl_info * pci)456 void edac_pci_remove_sysfs(struct edac_pci_ctl_info *pci)
457 {
458 	edac_dbg(0, "index=%d\n", pci->pci_idx);
459 
460 	/* Remove the symlink */
461 	sysfs_remove_link(&pci->kobj, EDAC_PCI_SYMLINK);
462 
463 	/* remove this PCI instance's sysfs entries */
464 	edac_pci_unregister_sysfs_instance_kobj(pci);
465 
466 	/* Call the main unregister function, which will determine
467 	 * if this 'pci' is the last instance.
468 	 * If it is, the main kobject will be unregistered as a result
469 	 */
470 	edac_dbg(0, "calling edac_pci_main_kobj_teardown()\n");
471 	edac_pci_main_kobj_teardown();
472 }
473 
474 /************************ PCI error handling *************************/
get_pci_parity_status(struct pci_dev * dev,int secondary)475 static u16 get_pci_parity_status(struct pci_dev *dev, int secondary)
476 {
477 	int where;
478 	u16 status;
479 
480 	where = secondary ? PCI_SEC_STATUS : PCI_STATUS;
481 	pci_read_config_word(dev, where, &status);
482 
483 	/* If we get back 0xFFFF then we must suspect that the card has been
484 	 * pulled but the Linux PCI layer has not yet finished cleaning up.
485 	 * We don't want to report on such devices
486 	 */
487 
488 	if (status == 0xFFFF) {
489 		u32 sanity;
490 
491 		pci_read_config_dword(dev, 0, &sanity);
492 
493 		if (sanity == 0xFFFFFFFF)
494 			return 0;
495 	}
496 
497 	status &= PCI_STATUS_DETECTED_PARITY | PCI_STATUS_SIG_SYSTEM_ERROR |
498 		PCI_STATUS_PARITY;
499 
500 	if (status)
501 		/* reset only the bits we are interested in */
502 		pci_write_config_word(dev, where, status);
503 
504 	return status;
505 }
506 
507 
508 /* Clear any PCI parity errors logged by this device. */
edac_pci_dev_parity_clear(struct pci_dev * dev)509 static void edac_pci_dev_parity_clear(struct pci_dev *dev)
510 {
511 	u8 header_type;
512 
513 	get_pci_parity_status(dev, 0);
514 
515 	/* read the device TYPE, looking for bridges */
516 	pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
517 
518 	if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE)
519 		get_pci_parity_status(dev, 1);
520 }
521 
522 /*
523  *  PCI Parity polling
524  *
525  *	Function to retrieve the current parity status
526  *	and decode it
527  *
528  */
edac_pci_dev_parity_test(struct pci_dev * dev)529 static void edac_pci_dev_parity_test(struct pci_dev *dev)
530 {
531 	unsigned long flags;
532 	u16 status;
533 	u8 header_type;
534 
535 	/* stop any interrupts until we can acquire the status */
536 	local_irq_save(flags);
537 
538 	/* read the STATUS register on this device */
539 	status = get_pci_parity_status(dev, 0);
540 
541 	/* read the device TYPE, looking for bridges */
542 	pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
543 
544 	local_irq_restore(flags);
545 
546 	edac_dbg(4, "PCI STATUS= 0x%04x %s\n", status, dev_name(&dev->dev));
547 
548 	/* check the status reg for errors on boards NOT marked as broken
549 	 * if broken, we cannot trust any of the status bits
550 	 */
551 	if (status && !dev->broken_parity_status) {
552 		if (status & (PCI_STATUS_SIG_SYSTEM_ERROR)) {
553 			edac_printk(KERN_CRIT, EDAC_PCI,
554 				"Signaled System Error on %s\n",
555 				pci_name(dev));
556 			atomic_inc(&pci_nonparity_count);
557 		}
558 
559 		if (status & (PCI_STATUS_PARITY)) {
560 			edac_printk(KERN_CRIT, EDAC_PCI,
561 				"Master Data Parity Error on %s\n",
562 				pci_name(dev));
563 
564 			atomic_inc(&pci_parity_count);
565 		}
566 
567 		if (status & (PCI_STATUS_DETECTED_PARITY)) {
568 			edac_printk(KERN_CRIT, EDAC_PCI,
569 				"Detected Parity Error on %s\n",
570 				pci_name(dev));
571 
572 			atomic_inc(&pci_parity_count);
573 		}
574 	}
575 
576 
577 	edac_dbg(4, "PCI HEADER TYPE= 0x%02x %s\n",
578 		 header_type, dev_name(&dev->dev));
579 
580 	if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE) {
581 		/* On bridges, need to examine secondary status register  */
582 		status = get_pci_parity_status(dev, 1);
583 
584 		edac_dbg(4, "PCI SEC_STATUS= 0x%04x %s\n",
585 			 status, dev_name(&dev->dev));
586 
587 		/* check the secondary status reg for errors,
588 		 * on NOT broken boards
589 		 */
590 		if (status && !dev->broken_parity_status) {
591 			if (status & (PCI_STATUS_SIG_SYSTEM_ERROR)) {
592 				edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
593 					"Signaled System Error on %s\n",
594 					pci_name(dev));
595 				atomic_inc(&pci_nonparity_count);
596 			}
597 
598 			if (status & (PCI_STATUS_PARITY)) {
599 				edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
600 					"Master Data Parity Error on "
601 					"%s\n", pci_name(dev));
602 
603 				atomic_inc(&pci_parity_count);
604 			}
605 
606 			if (status & (PCI_STATUS_DETECTED_PARITY)) {
607 				edac_printk(KERN_CRIT, EDAC_PCI, "Bridge "
608 					"Detected Parity Error on %s\n",
609 					pci_name(dev));
610 
611 				atomic_inc(&pci_parity_count);
612 			}
613 		}
614 	}
615 }
616 
617 /* reduce some complexity in definition of the iterator */
618 typedef void (*pci_parity_check_fn_t) (struct pci_dev *dev);
619 
620 /*
621  * pci_dev parity list iterator
622  *
623  *	Scan the PCI device list looking for SERRORs, Master Parity ERRORS or
624  *	Parity ERRORs on primary or secondary devices.
625  */
edac_pci_dev_parity_iterator(pci_parity_check_fn_t fn)626 static inline void edac_pci_dev_parity_iterator(pci_parity_check_fn_t fn)
627 {
628 	struct pci_dev *dev = NULL;
629 
630 	for_each_pci_dev(dev)
631 		fn(dev);
632 }
633 
634 /*
635  * edac_pci_do_parity_check
636  *
637  *	performs the actual PCI parity check operation
638  */
edac_pci_do_parity_check(void)639 void edac_pci_do_parity_check(void)
640 {
641 	int before_count;
642 
643 	edac_dbg(3, "\n");
644 
645 	/* if policy has PCI check off, leave now */
646 	if (!check_pci_errors)
647 		return;
648 
649 	before_count = atomic_read(&pci_parity_count);
650 
651 	/* scan all PCI devices looking for a Parity Error on devices and
652 	 * bridges.
653 	 * The iterator calls pci_get_device() which might sleep, thus
654 	 * we cannot disable interrupts in this scan.
655 	 */
656 	edac_pci_dev_parity_iterator(edac_pci_dev_parity_test);
657 
658 	/* Only if operator has selected panic on PCI Error */
659 	if (edac_pci_get_panic_on_pe()) {
660 		/* If the count is different 'after' from 'before' */
661 		if (before_count != atomic_read(&pci_parity_count))
662 			panic("EDAC: PCI Parity Error");
663 	}
664 }
665 
666 /*
667  * edac_pci_clear_parity_errors
668  *
669  *	function to perform an iteration over the PCI devices
670  *	and clearn their current status
671  */
edac_pci_clear_parity_errors(void)672 void edac_pci_clear_parity_errors(void)
673 {
674 	/* Clear any PCI bus parity errors that devices initially have logged
675 	 * in their registers.
676 	 */
677 	edac_pci_dev_parity_iterator(edac_pci_dev_parity_clear);
678 }
679 
680 /*
681  * edac_pci_handle_pe
682  *
683  *	Called to handle a PARITY ERROR event
684  */
edac_pci_handle_pe(struct edac_pci_ctl_info * pci,const char * msg)685 void edac_pci_handle_pe(struct edac_pci_ctl_info *pci, const char *msg)
686 {
687 
688 	/* global PE counter incremented by edac_pci_do_parity_check() */
689 	atomic_inc(&pci->counters.pe_count);
690 
691 	if (edac_pci_get_log_pe())
692 		edac_pci_printk(pci, KERN_WARNING,
693 				"Parity Error ctl: %s %d: %s\n",
694 				pci->ctl_name, pci->pci_idx, msg);
695 
696 	/*
697 	 * poke all PCI devices and see which one is the troublemaker
698 	 * panic() is called if set
699 	 */
700 	edac_pci_do_parity_check();
701 }
702 EXPORT_SYMBOL_GPL(edac_pci_handle_pe);
703 
704 
705 /*
706  * edac_pci_handle_npe
707  *
708  *	Called to handle a NON-PARITY ERROR event
709  */
edac_pci_handle_npe(struct edac_pci_ctl_info * pci,const char * msg)710 void edac_pci_handle_npe(struct edac_pci_ctl_info *pci, const char *msg)
711 {
712 
713 	/* global NPE counter incremented by edac_pci_do_parity_check() */
714 	atomic_inc(&pci->counters.npe_count);
715 
716 	if (edac_pci_get_log_npe())
717 		edac_pci_printk(pci, KERN_WARNING,
718 				"Non-Parity Error ctl: %s %d: %s\n",
719 				pci->ctl_name, pci->pci_idx, msg);
720 
721 	/*
722 	 * poke all PCI devices and see which one is the troublemaker
723 	 * panic() is called if set
724 	 */
725 	edac_pci_do_parity_check();
726 }
727 EXPORT_SYMBOL_GPL(edac_pci_handle_npe);
728 
729 /*
730  * Define the PCI parameter to the module
731  */
732 module_param(check_pci_errors, int, 0644);
733 MODULE_PARM_DESC(check_pci_errors,
734 		 "Check for PCI bus parity errors: 0=off 1=on");
735 module_param(edac_pci_panic_on_pe, int, 0644);
736 MODULE_PARM_DESC(edac_pci_panic_on_pe,
737 		 "Panic on PCI Bus Parity error: 0=off 1=on");
738