xref: /linux/drivers/edac/edac_mc_sysfs.c (revision 7fc2cd2e4b398c57c9cf961cfea05eadbf34c05c)
1 /*
2  * edac_mc kernel module
3  * (C) 2005-2007 Linux Networx (http://lnxi.com)
4  *
5  * This file may be distributed under the terms of the
6  * GNU General Public License.
7  *
8  * Written Doug Thompson <norsk5@xmission.com> www.softwarebitmaker.com
9  *
10  * (c) 2012-2013 - Mauro Carvalho Chehab
11  *	The entire API were re-written, and ported to use struct device
12  *
13  */
14 
15 #include <linux/ctype.h>
16 #include <linux/slab.h>
17 #include <linux/edac.h>
18 #include <linux/bug.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/uaccess.h>
21 
22 #include "edac_mc.h"
23 #include "edac_module.h"
24 
25 /* MC EDAC Controls, setable by module parameter, and sysfs */
26 static int edac_mc_log_ue = 1;
27 static int edac_mc_log_ce = 1;
28 static int edac_mc_panic_on_ue;
29 static unsigned int edac_mc_poll_msec = 1000;
30 
31 /* Getter functions for above */
32 int edac_mc_get_log_ue(void)
33 {
34 	return edac_mc_log_ue;
35 }
36 
37 int edac_mc_get_log_ce(void)
38 {
39 	return edac_mc_log_ce;
40 }
41 
42 int edac_mc_get_panic_on_ue(void)
43 {
44 	return edac_mc_panic_on_ue;
45 }
46 
47 /* this is temporary */
48 unsigned int edac_mc_get_poll_msec(void)
49 {
50 	return edac_mc_poll_msec;
51 }
52 
53 static int edac_set_poll_msec(const char *val, const struct kernel_param *kp)
54 {
55 	unsigned int i;
56 	int ret;
57 
58 	if (!val)
59 		return -EINVAL;
60 
61 	ret = kstrtouint(val, 0, &i);
62 	if (ret)
63 		return ret;
64 
65 	if (i < 1000)
66 		return -EINVAL;
67 
68 	*((unsigned int *)kp->arg) = i;
69 
70 	/* notify edac_mc engine to reset the poll period */
71 	edac_mc_reset_delay_period(i);
72 
73 	return 0;
74 }
75 
76 /* Parameter declarations for above */
77 module_param(edac_mc_panic_on_ue, int, 0644);
78 MODULE_PARM_DESC(edac_mc_panic_on_ue, "Panic on uncorrected error: 0=off 1=on");
79 module_param(edac_mc_log_ue, int, 0644);
80 MODULE_PARM_DESC(edac_mc_log_ue,
81 		 "Log uncorrectable error to console: 0=off 1=on");
82 module_param(edac_mc_log_ce, int, 0644);
83 MODULE_PARM_DESC(edac_mc_log_ce,
84 		 "Log correctable error to console: 0=off 1=on");
85 module_param_call(edac_mc_poll_msec, edac_set_poll_msec, param_get_uint,
86 		  &edac_mc_poll_msec, 0644);
87 MODULE_PARM_DESC(edac_mc_poll_msec, "Polling period in milliseconds");
88 
89 static struct device *mci_pdev;
90 
91 /*
92  * various constants for Memory Controllers
93  */
94 static const char * const dev_types[] = {
95 	[DEV_UNKNOWN] = "Unknown",
96 	[DEV_X1] = "x1",
97 	[DEV_X2] = "x2",
98 	[DEV_X4] = "x4",
99 	[DEV_X8] = "x8",
100 	[DEV_X16] = "x16",
101 	[DEV_X32] = "x32",
102 	[DEV_X64] = "x64"
103 };
104 
105 static const char * const edac_caps[] = {
106 	[EDAC_UNKNOWN] = "Unknown",
107 	[EDAC_NONE] = "None",
108 	[EDAC_RESERVED] = "Reserved",
109 	[EDAC_PARITY] = "PARITY",
110 	[EDAC_EC] = "EC",
111 	[EDAC_SECDED] = "SECDED",
112 	[EDAC_S2ECD2ED] = "S2ECD2ED",
113 	[EDAC_S4ECD4ED] = "S4ECD4ED",
114 	[EDAC_S8ECD8ED] = "S8ECD8ED",
115 	[EDAC_S16ECD16ED] = "S16ECD16ED"
116 };
117 
118 /*
119  * Per-dimm (or per-rank) devices
120  */
121 
122 #define to_dimm(k) container_of(k, struct dimm_info, dev)
123 
124 /* show/store functions for DIMM Label attributes */
125 static ssize_t dimmdev_location_show(struct device *dev,
126 				     struct device_attribute *mattr, char *data)
127 {
128 	struct dimm_info *dimm = to_dimm(dev);
129 	ssize_t count;
130 
131 	count = edac_dimm_info_location(dimm, data, PAGE_SIZE);
132 	count += scnprintf(data + count, PAGE_SIZE - count, "\n");
133 
134 	return count;
135 }
136 
137 static ssize_t dimmdev_label_show(struct device *dev,
138 				  struct device_attribute *mattr, char *data)
139 {
140 	struct dimm_info *dimm = to_dimm(dev);
141 
142 	/* if field has not been initialized, there is nothing to send */
143 	if (!dimm->label[0])
144 		return 0;
145 
146 	return sysfs_emit(data, "%s\n", dimm->label);
147 }
148 
149 static ssize_t dimmdev_label_store(struct device *dev,
150 				   struct device_attribute *mattr,
151 				   const char *data,
152 				   size_t count)
153 {
154 	struct dimm_info *dimm = to_dimm(dev);
155 	size_t copy_count = count;
156 
157 	if (count == 0)
158 		return -EINVAL;
159 
160 	if (data[count - 1] == '\0' || data[count - 1] == '\n')
161 		copy_count -= 1;
162 
163 	if (copy_count == 0 || copy_count >= sizeof(dimm->label))
164 		return -EINVAL;
165 
166 	memcpy(dimm->label, data, copy_count);
167 	dimm->label[copy_count] = '\0';
168 
169 	return count;
170 }
171 
172 static ssize_t dimmdev_size_show(struct device *dev,
173 				 struct device_attribute *mattr, char *data)
174 {
175 	struct dimm_info *dimm = to_dimm(dev);
176 
177 	return sysfs_emit(data, "%u\n", PAGES_TO_MiB(dimm->nr_pages));
178 }
179 
180 static ssize_t dimmdev_mem_type_show(struct device *dev,
181 				     struct device_attribute *mattr, char *data)
182 {
183 	struct dimm_info *dimm = to_dimm(dev);
184 
185 	return sysfs_emit(data, "%s\n", edac_mem_types[dimm->mtype]);
186 }
187 
188 static ssize_t dimmdev_dev_type_show(struct device *dev,
189 				     struct device_attribute *mattr, char *data)
190 {
191 	struct dimm_info *dimm = to_dimm(dev);
192 
193 	return sysfs_emit(data, "%s\n", dev_types[dimm->dtype]);
194 }
195 
196 static ssize_t dimmdev_edac_mode_show(struct device *dev,
197 				      struct device_attribute *mattr,
198 				      char *data)
199 {
200 	struct dimm_info *dimm = to_dimm(dev);
201 
202 	return sysfs_emit(data, "%s\n", edac_caps[dimm->edac_mode]);
203 }
204 
205 static ssize_t dimmdev_ce_count_show(struct device *dev,
206 				      struct device_attribute *mattr,
207 				      char *data)
208 {
209 	struct dimm_info *dimm = to_dimm(dev);
210 
211 	return sysfs_emit(data, "%u\n", dimm->ce_count);
212 }
213 
214 static ssize_t dimmdev_ue_count_show(struct device *dev,
215 				      struct device_attribute *mattr,
216 				      char *data)
217 {
218 	struct dimm_info *dimm = to_dimm(dev);
219 
220 	return sysfs_emit(data, "%u\n", dimm->ue_count);
221 }
222 
223 /* dimm/rank attribute files */
224 static DEVICE_ATTR(dimm_label, S_IRUGO | S_IWUSR,
225 		   dimmdev_label_show, dimmdev_label_store);
226 static DEVICE_ATTR(dimm_location, S_IRUGO, dimmdev_location_show, NULL);
227 static DEVICE_ATTR(size, S_IRUGO, dimmdev_size_show, NULL);
228 static DEVICE_ATTR(dimm_mem_type, S_IRUGO, dimmdev_mem_type_show, NULL);
229 static DEVICE_ATTR(dimm_dev_type, S_IRUGO, dimmdev_dev_type_show, NULL);
230 static DEVICE_ATTR(dimm_edac_mode, S_IRUGO, dimmdev_edac_mode_show, NULL);
231 static DEVICE_ATTR(dimm_ce_count, S_IRUGO, dimmdev_ce_count_show, NULL);
232 static DEVICE_ATTR(dimm_ue_count, S_IRUGO, dimmdev_ue_count_show, NULL);
233 
234 /* attributes of the dimm<id>/rank<id> object */
235 static struct attribute *dimm_attrs[] = {
236 	&dev_attr_dimm_label.attr,
237 	&dev_attr_dimm_location.attr,
238 	&dev_attr_size.attr,
239 	&dev_attr_dimm_mem_type.attr,
240 	&dev_attr_dimm_dev_type.attr,
241 	&dev_attr_dimm_edac_mode.attr,
242 	&dev_attr_dimm_ce_count.attr,
243 	&dev_attr_dimm_ue_count.attr,
244 	NULL,
245 };
246 
247 static const struct attribute_group dimm_attr_grp = {
248 	.attrs	= dimm_attrs,
249 };
250 
251 static const struct attribute_group *dimm_attr_groups[] = {
252 	&dimm_attr_grp,
253 	NULL
254 };
255 
256 static const struct device_type dimm_attr_type = {
257 	.groups		= dimm_attr_groups,
258 };
259 
260 static void dimm_release(struct device *dev)
261 {
262 	/*
263 	 * Nothing to do, just unregister sysfs here. The mci
264 	 * device owns the data and will also release it.
265 	 */
266 }
267 
268 /* Create a DIMM object under specified memory controller device */
269 static int edac_create_dimm_object(struct mem_ctl_info *mci,
270 				   struct dimm_info *dimm)
271 {
272 	int err;
273 	dimm->mci = mci;
274 
275 	dimm->dev.type = &dimm_attr_type;
276 	dimm->dev.release = dimm_release;
277 	device_initialize(&dimm->dev);
278 
279 	dimm->dev.parent = &mci->dev;
280 	if (mci->csbased)
281 		dev_set_name(&dimm->dev, "rank%d", dimm->idx);
282 	else
283 		dev_set_name(&dimm->dev, "dimm%d", dimm->idx);
284 	dev_set_drvdata(&dimm->dev, dimm);
285 	pm_runtime_forbid(&mci->dev);
286 
287 	err = device_add(&dimm->dev);
288 	if (err) {
289 		edac_dbg(1, "failure: create device %s\n", dev_name(&dimm->dev));
290 		put_device(&dimm->dev);
291 		return err;
292 	}
293 
294 	if (IS_ENABLED(CONFIG_EDAC_DEBUG)) {
295 		char location[80];
296 
297 		edac_dimm_info_location(dimm, location, sizeof(location));
298 		edac_dbg(0, "device %s created at location %s\n",
299 			dev_name(&dimm->dev), location);
300 	}
301 
302 	return 0;
303 }
304 
305 /*
306  * Memory controller device
307  */
308 
309 #define to_mci(k) container_of(k, struct mem_ctl_info, dev)
310 
311 static ssize_t mci_reset_counters_store(struct device *dev,
312 					struct device_attribute *mattr,
313 					const char *data, size_t count)
314 {
315 	struct mem_ctl_info *mci = to_mci(dev);
316 	struct dimm_info *dimm;
317 	int row, chan;
318 
319 	mci->ue_mc = 0;
320 	mci->ce_mc = 0;
321 	mci->ue_noinfo_count = 0;
322 	mci->ce_noinfo_count = 0;
323 
324 	for (row = 0; row < mci->nr_csrows; row++) {
325 		struct csrow_info *ri = mci->csrows[row];
326 
327 		ri->ue_count = 0;
328 		ri->ce_count = 0;
329 
330 		for (chan = 0; chan < ri->nr_channels; chan++)
331 			ri->channels[chan]->ce_count = 0;
332 	}
333 
334 	mci_for_each_dimm(mci, dimm) {
335 		dimm->ue_count = 0;
336 		dimm->ce_count = 0;
337 	}
338 
339 	mci->start_time = jiffies;
340 	return count;
341 }
342 
343 /* Memory scrubbing interface:
344  *
345  * A MC driver can limit the scrubbing bandwidth based on the CPU type.
346  * Therefore, ->set_sdram_scrub_rate should be made to return the actual
347  * bandwidth that is accepted or 0 when scrubbing is to be disabled.
348  *
349  * Negative value still means that an error has occurred while setting
350  * the scrub rate.
351  */
352 static ssize_t mci_sdram_scrub_rate_store(struct device *dev,
353 					  struct device_attribute *mattr,
354 					  const char *data, size_t count)
355 {
356 	struct mem_ctl_info *mci = to_mci(dev);
357 	unsigned long bandwidth = 0;
358 	int new_bw = 0;
359 
360 	if (kstrtoul(data, 10, &bandwidth) < 0)
361 		return -EINVAL;
362 
363 	new_bw = mci->set_sdram_scrub_rate(mci, bandwidth);
364 	if (new_bw < 0) {
365 		edac_printk(KERN_WARNING, EDAC_MC,
366 			    "Error setting scrub rate to: %lu\n", bandwidth);
367 		return -EINVAL;
368 	}
369 
370 	return count;
371 }
372 
373 /*
374  * ->get_sdram_scrub_rate() return value semantics same as above.
375  */
376 static ssize_t mci_sdram_scrub_rate_show(struct device *dev,
377 					 struct device_attribute *mattr,
378 					 char *data)
379 {
380 	struct mem_ctl_info *mci = to_mci(dev);
381 	int bandwidth = 0;
382 
383 	bandwidth = mci->get_sdram_scrub_rate(mci);
384 	if (bandwidth < 0) {
385 		edac_printk(KERN_DEBUG, EDAC_MC, "Error reading scrub rate\n");
386 		return bandwidth;
387 	}
388 
389 	return sysfs_emit(data, "%d\n", bandwidth);
390 }
391 
392 /* default attribute files for the MCI object */
393 static ssize_t mci_ue_count_show(struct device *dev,
394 				 struct device_attribute *mattr,
395 				 char *data)
396 {
397 	struct mem_ctl_info *mci = to_mci(dev);
398 
399 	return sysfs_emit(data, "%u\n", mci->ue_mc);
400 }
401 
402 static ssize_t mci_ce_count_show(struct device *dev,
403 				 struct device_attribute *mattr,
404 				 char *data)
405 {
406 	struct mem_ctl_info *mci = to_mci(dev);
407 
408 	return sysfs_emit(data, "%u\n", mci->ce_mc);
409 }
410 
411 static ssize_t mci_ce_noinfo_show(struct device *dev,
412 				  struct device_attribute *mattr,
413 				  char *data)
414 {
415 	struct mem_ctl_info *mci = to_mci(dev);
416 
417 	return sysfs_emit(data, "%u\n", mci->ce_noinfo_count);
418 }
419 
420 static ssize_t mci_ue_noinfo_show(struct device *dev,
421 				  struct device_attribute *mattr,
422 				  char *data)
423 {
424 	struct mem_ctl_info *mci = to_mci(dev);
425 
426 	return sysfs_emit(data, "%u\n", mci->ue_noinfo_count);
427 }
428 
429 static ssize_t mci_seconds_show(struct device *dev,
430 				struct device_attribute *mattr,
431 				char *data)
432 {
433 	struct mem_ctl_info *mci = to_mci(dev);
434 
435 	return sysfs_emit(data, "%ld\n", (jiffies - mci->start_time) / HZ);
436 }
437 
438 static ssize_t mci_ctl_name_show(struct device *dev,
439 				 struct device_attribute *mattr,
440 				 char *data)
441 {
442 	struct mem_ctl_info *mci = to_mci(dev);
443 
444 	return sysfs_emit(data, "%s\n", mci->ctl_name);
445 }
446 
447 static ssize_t mci_size_mb_show(struct device *dev,
448 				struct device_attribute *mattr,
449 				char *data)
450 {
451 	struct mem_ctl_info *mci = to_mci(dev);
452 	int total_pages = 0, csrow_idx, j;
453 
454 	for (csrow_idx = 0; csrow_idx < mci->nr_csrows; csrow_idx++) {
455 		struct csrow_info *csrow = mci->csrows[csrow_idx];
456 
457 		for (j = 0; j < csrow->nr_channels; j++) {
458 			struct dimm_info *dimm = csrow->channels[j]->dimm;
459 
460 			total_pages += dimm->nr_pages;
461 		}
462 	}
463 
464 	return sysfs_emit(data, "%u\n", PAGES_TO_MiB(total_pages));
465 }
466 
467 static ssize_t mci_max_location_show(struct device *dev,
468 				     struct device_attribute *mattr,
469 				     char *data)
470 {
471 	struct mem_ctl_info *mci = to_mci(dev);
472 	int len = PAGE_SIZE;
473 	char *p = data;
474 	int i, n;
475 
476 	for (i = 0; i < mci->n_layers; i++) {
477 		n = scnprintf(p, len, "%s %d ",
478 			      edac_layer_name[mci->layers[i].type],
479 			      mci->layers[i].size - 1);
480 		len -= n;
481 		if (len <= 0)
482 			goto out;
483 
484 		p += n;
485 	}
486 
487 	p += scnprintf(p, len, "\n");
488 out:
489 	return p - data;
490 }
491 
492 /* default Control file */
493 static DEVICE_ATTR(reset_counters, S_IWUSR, NULL, mci_reset_counters_store);
494 
495 /* default Attribute files */
496 static DEVICE_ATTR(mc_name, S_IRUGO, mci_ctl_name_show, NULL);
497 static DEVICE_ATTR(size_mb, S_IRUGO, mci_size_mb_show, NULL);
498 static DEVICE_ATTR(seconds_since_reset, S_IRUGO, mci_seconds_show, NULL);
499 static DEVICE_ATTR(ue_noinfo_count, S_IRUGO, mci_ue_noinfo_show, NULL);
500 static DEVICE_ATTR(ce_noinfo_count, S_IRUGO, mci_ce_noinfo_show, NULL);
501 static DEVICE_ATTR(ue_count, S_IRUGO, mci_ue_count_show, NULL);
502 static DEVICE_ATTR(ce_count, S_IRUGO, mci_ce_count_show, NULL);
503 static DEVICE_ATTR(max_location, S_IRUGO, mci_max_location_show, NULL);
504 
505 /* memory scrubber attribute file */
506 static DEVICE_ATTR(sdram_scrub_rate, 0, mci_sdram_scrub_rate_show,
507 	    mci_sdram_scrub_rate_store); /* umode set later in is_visible */
508 
509 static struct attribute *mci_attrs[] = {
510 	&dev_attr_reset_counters.attr,
511 	&dev_attr_mc_name.attr,
512 	&dev_attr_size_mb.attr,
513 	&dev_attr_seconds_since_reset.attr,
514 	&dev_attr_ue_noinfo_count.attr,
515 	&dev_attr_ce_noinfo_count.attr,
516 	&dev_attr_ue_count.attr,
517 	&dev_attr_ce_count.attr,
518 	&dev_attr_max_location.attr,
519 	&dev_attr_sdram_scrub_rate.attr,
520 	NULL
521 };
522 
523 static umode_t mci_attr_is_visible(struct kobject *kobj,
524 				   struct attribute *attr, int idx)
525 {
526 	struct device *dev = kobj_to_dev(kobj);
527 	struct mem_ctl_info *mci = to_mci(dev);
528 	umode_t mode = 0;
529 
530 	if (attr != &dev_attr_sdram_scrub_rate.attr)
531 		return attr->mode;
532 	if (mci->get_sdram_scrub_rate)
533 		mode |= S_IRUGO;
534 	if (mci->set_sdram_scrub_rate)
535 		mode |= S_IWUSR;
536 	return mode;
537 }
538 
539 static const struct attribute_group mci_attr_grp = {
540 	.attrs	= mci_attrs,
541 	.is_visible = mci_attr_is_visible,
542 };
543 
544 static const struct attribute_group *mci_attr_groups[] = {
545 	&mci_attr_grp,
546 	NULL
547 };
548 
549 static const struct device_type mci_attr_type = {
550 	.groups		= mci_attr_groups,
551 };
552 
553 /*
554  * Create a new Memory Controller kobject instance,
555  *	mc<id> under the 'mc' directory
556  *
557  * Return:
558  *	0	Success
559  *	!0	Failure
560  */
561 int edac_create_sysfs_mci_device(struct mem_ctl_info *mci,
562 				 const struct attribute_group **groups)
563 {
564 	struct dimm_info *dimm;
565 	int err;
566 
567 	/* get the /sys/devices/system/edac subsys reference */
568 	mci->dev.type = &mci_attr_type;
569 	mci->dev.parent = mci_pdev;
570 	mci->dev.groups = groups;
571 	dev_set_name(&mci->dev, "mc%d", mci->mc_idx);
572 	dev_set_drvdata(&mci->dev, mci);
573 	pm_runtime_forbid(&mci->dev);
574 
575 	err = device_add(&mci->dev);
576 	if (err < 0) {
577 		edac_dbg(1, "failure: create device %s\n", dev_name(&mci->dev));
578 		/* no put_device() here, free mci with _edac_mc_free() */
579 		return err;
580 	}
581 
582 	edac_dbg(0, "device %s created\n", dev_name(&mci->dev));
583 
584 	/*
585 	 * Create the dimm/rank devices
586 	 */
587 	mci_for_each_dimm(mci, dimm) {
588 		/* Only expose populated DIMMs */
589 		if (!dimm->nr_pages)
590 			continue;
591 
592 		err = edac_create_dimm_object(mci, dimm);
593 		if (err)
594 			goto fail;
595 	}
596 
597 	edac_create_debugfs_nodes(mci);
598 	return 0;
599 
600 fail:
601 	edac_remove_sysfs_mci_device(mci);
602 
603 	return err;
604 }
605 
606 /*
607  * remove a Memory Controller instance
608  */
609 void edac_remove_sysfs_mci_device(struct mem_ctl_info *mci)
610 {
611 	struct dimm_info *dimm;
612 
613 	if (!device_is_registered(&mci->dev))
614 		return;
615 
616 	edac_dbg(0, "\n");
617 
618 #ifdef CONFIG_EDAC_DEBUG
619 	edac_debugfs_remove_recursive(mci->debugfs);
620 #endif
621 
622 	mci_for_each_dimm(mci, dimm) {
623 		if (!device_is_registered(&dimm->dev))
624 			continue;
625 		edac_dbg(1, "unregistering device %s\n", dev_name(&dimm->dev));
626 		device_unregister(&dimm->dev);
627 	}
628 
629 	/* only remove the device, but keep mci */
630 	device_del(&mci->dev);
631 }
632 
633 static void mc_attr_release(struct device *dev)
634 {
635 	/*
636 	 * There's no container structure here, as this is just the mci
637 	 * parent device, used to create the /sys/devices/mc sysfs node.
638 	 * So, there are no attributes on it.
639 	 */
640 	edac_dbg(1, "device %s released\n", dev_name(dev));
641 	kfree(dev);
642 }
643 
644 /*
645  * Init/exit code for the module. Basically, creates/removes /sys/class/rc
646  */
647 int __init edac_mc_sysfs_init(void)
648 {
649 	int err;
650 
651 	mci_pdev = kzalloc(sizeof(*mci_pdev), GFP_KERNEL);
652 	if (!mci_pdev)
653 		return -ENOMEM;
654 
655 	mci_pdev->bus = edac_get_sysfs_subsys();
656 	mci_pdev->release = mc_attr_release;
657 	mci_pdev->init_name = "mc";
658 
659 	err = device_register(mci_pdev);
660 	if (err < 0) {
661 		edac_dbg(1, "failure: create device %s\n", dev_name(mci_pdev));
662 		put_device(mci_pdev);
663 		return err;
664 	}
665 
666 	edac_dbg(0, "device %s created\n", dev_name(mci_pdev));
667 
668 	return 0;
669 }
670 
671 void edac_mc_sysfs_exit(void)
672 {
673 	device_unregister(mci_pdev);
674 }
675