Merge branch 'for-5.6' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie...
[linux-2.6-microblaze.git] / drivers / devfreq / event / exynos-ppmu.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * exynos_ppmu.c - Exynos PPMU (Platform Performance Monitoring Unit) support
4  *
5  * Copyright (c) 2014-2015 Samsung Electronics Co., Ltd.
6  * Author : Chanwoo Choi <cw00.choi@samsung.com>
7  *
8  * This driver is based on drivers/devfreq/exynos/exynos_ppmu.c
9  */
10
11 #include <linux/clk.h>
12 #include <linux/io.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/of_address.h>
16 #include <linux/of_device.h>
17 #include <linux/platform_device.h>
18 #include <linux/regmap.h>
19 #include <linux/suspend.h>
20 #include <linux/devfreq-event.h>
21
22 #include "exynos-ppmu.h"
23
24 enum exynos_ppmu_type {
25         EXYNOS_TYPE_PPMU,
26         EXYNOS_TYPE_PPMU_V2,
27 };
28
29 struct exynos_ppmu_data {
30         struct clk *clk;
31 };
32
33 struct exynos_ppmu {
34         struct devfreq_event_dev **edev;
35         struct devfreq_event_desc *desc;
36         unsigned int num_events;
37
38         struct device *dev;
39         struct regmap *regmap;
40
41         struct exynos_ppmu_data ppmu;
42         enum exynos_ppmu_type ppmu_type;
43 };
44
45 #define PPMU_EVENT(name)                        \
46         { "ppmu-event0-"#name, PPMU_PMNCNT0 },  \
47         { "ppmu-event1-"#name, PPMU_PMNCNT1 },  \
48         { "ppmu-event2-"#name, PPMU_PMNCNT2 },  \
49         { "ppmu-event3-"#name, PPMU_PMNCNT3 }
50
51 static struct __exynos_ppmu_events {
52         char *name;
53         int id;
54 } ppmu_events[] = {
55         /* For Exynos3250, Exynos4 and Exynos5260 */
56         PPMU_EVENT(g3d),
57         PPMU_EVENT(fsys),
58
59         /* For Exynos4 SoCs and Exynos3250 */
60         PPMU_EVENT(dmc0),
61         PPMU_EVENT(dmc1),
62         PPMU_EVENT(cpu),
63         PPMU_EVENT(rightbus),
64         PPMU_EVENT(leftbus),
65         PPMU_EVENT(lcd0),
66         PPMU_EVENT(camif),
67
68         /* Only for Exynos3250 and Exynos5260 */
69         PPMU_EVENT(mfc),
70
71         /* Only for Exynos4 SoCs */
72         PPMU_EVENT(mfc-left),
73         PPMU_EVENT(mfc-right),
74
75         /* Only for Exynos5260 SoCs */
76         PPMU_EVENT(drex0-s0),
77         PPMU_EVENT(drex0-s1),
78         PPMU_EVENT(drex1-s0),
79         PPMU_EVENT(drex1-s1),
80         PPMU_EVENT(eagle),
81         PPMU_EVENT(kfc),
82         PPMU_EVENT(isp),
83         PPMU_EVENT(fimc),
84         PPMU_EVENT(gscl),
85         PPMU_EVENT(mscl),
86         PPMU_EVENT(fimd0x),
87         PPMU_EVENT(fimd1x),
88
89         /* Only for Exynos5433 SoCs */
90         PPMU_EVENT(d0-cpu),
91         PPMU_EVENT(d0-general),
92         PPMU_EVENT(d0-rt),
93         PPMU_EVENT(d1-cpu),
94         PPMU_EVENT(d1-general),
95         PPMU_EVENT(d1-rt),
96
97         /* For Exynos5422 SoC */
98         PPMU_EVENT(dmc0_0),
99         PPMU_EVENT(dmc0_1),
100         PPMU_EVENT(dmc1_0),
101         PPMU_EVENT(dmc1_1),
102 };
103
104 static int __exynos_ppmu_find_ppmu_id(const char *edev_name)
105 {
106         int i;
107
108         for (i = 0; i < ARRAY_SIZE(ppmu_events); i++)
109                 if (!strcmp(edev_name, ppmu_events[i].name))
110                         return ppmu_events[i].id;
111
112         return -EINVAL;
113 }
114
115 static int exynos_ppmu_find_ppmu_id(struct devfreq_event_dev *edev)
116 {
117         return __exynos_ppmu_find_ppmu_id(edev->desc->name);
118 }
119
120 /*
121  * The devfreq-event ops structure for PPMU v1.1
122  */
123 static int exynos_ppmu_disable(struct devfreq_event_dev *edev)
124 {
125         struct exynos_ppmu *info = devfreq_event_get_drvdata(edev);
126         int ret;
127         u32 pmnc;
128
129         /* Disable all counters */
130         ret = regmap_write(info->regmap, PPMU_CNTENC,
131                                 PPMU_CCNT_MASK |
132                                 PPMU_PMCNT0_MASK |
133                                 PPMU_PMCNT1_MASK |
134                                 PPMU_PMCNT2_MASK |
135                                 PPMU_PMCNT3_MASK);
136         if (ret < 0)
137                 return ret;
138
139         /* Disable PPMU */
140         ret = regmap_read(info->regmap, PPMU_PMNC, &pmnc);
141         if (ret < 0)
142                 return ret;
143
144         pmnc &= ~PPMU_PMNC_ENABLE_MASK;
145         ret = regmap_write(info->regmap, PPMU_PMNC, pmnc);
146         if (ret < 0)
147                 return ret;
148
149         return 0;
150 }
151
152 static int exynos_ppmu_set_event(struct devfreq_event_dev *edev)
153 {
154         struct exynos_ppmu *info = devfreq_event_get_drvdata(edev);
155         int id = exynos_ppmu_find_ppmu_id(edev);
156         int ret;
157         u32 pmnc, cntens;
158
159         if (id < 0)
160                 return id;
161
162         /* Enable specific counter */
163         ret = regmap_read(info->regmap, PPMU_CNTENS, &cntens);
164         if (ret < 0)
165                 return ret;
166
167         cntens |= (PPMU_CCNT_MASK | (PPMU_ENABLE << id));
168         ret = regmap_write(info->regmap, PPMU_CNTENS, cntens);
169         if (ret < 0)
170                 return ret;
171
172         /* Set the event of proper data type monitoring */
173         ret = regmap_write(info->regmap, PPMU_BEVTxSEL(id),
174                            edev->desc->event_type);
175         if (ret < 0)
176                 return ret;
177
178         /* Reset cycle counter/performance counter and enable PPMU */
179         ret = regmap_read(info->regmap, PPMU_PMNC, &pmnc);
180         if (ret < 0)
181                 return ret;
182
183         pmnc &= ~(PPMU_PMNC_ENABLE_MASK
184                         | PPMU_PMNC_COUNTER_RESET_MASK
185                         | PPMU_PMNC_CC_RESET_MASK);
186         pmnc |= (PPMU_ENABLE << PPMU_PMNC_ENABLE_SHIFT);
187         pmnc |= (PPMU_ENABLE << PPMU_PMNC_COUNTER_RESET_SHIFT);
188         pmnc |= (PPMU_ENABLE << PPMU_PMNC_CC_RESET_SHIFT);
189         ret = regmap_write(info->regmap, PPMU_PMNC, pmnc);
190         if (ret < 0)
191                 return ret;
192
193         return 0;
194 }
195
196 static int exynos_ppmu_get_event(struct devfreq_event_dev *edev,
197                                 struct devfreq_event_data *edata)
198 {
199         struct exynos_ppmu *info = devfreq_event_get_drvdata(edev);
200         int id = exynos_ppmu_find_ppmu_id(edev);
201         unsigned int total_count, load_count;
202         unsigned int pmcnt3_high, pmcnt3_low;
203         unsigned int pmnc, cntenc;
204         int ret;
205
206         if (id < 0)
207                 return -EINVAL;
208
209         /* Disable PPMU */
210         ret = regmap_read(info->regmap, PPMU_PMNC, &pmnc);
211         if (ret < 0)
212                 return ret;
213
214         pmnc &= ~PPMU_PMNC_ENABLE_MASK;
215         ret = regmap_write(info->regmap, PPMU_PMNC, pmnc);
216         if (ret < 0)
217                 return ret;
218
219         /* Read cycle count */
220         ret = regmap_read(info->regmap, PPMU_CCNT, &total_count);
221         if (ret < 0)
222                 return ret;
223         edata->total_count = total_count;
224
225         /* Read performance count */
226         switch (id) {
227         case PPMU_PMNCNT0:
228         case PPMU_PMNCNT1:
229         case PPMU_PMNCNT2:
230                 ret = regmap_read(info->regmap, PPMU_PMNCT(id), &load_count);
231                 if (ret < 0)
232                         return ret;
233                 edata->load_count = load_count;
234                 break;
235         case PPMU_PMNCNT3:
236                 ret = regmap_read(info->regmap, PPMU_PMCNT3_HIGH, &pmcnt3_high);
237                 if (ret < 0)
238                         return ret;
239
240                 ret = regmap_read(info->regmap, PPMU_PMCNT3_LOW, &pmcnt3_low);
241                 if (ret < 0)
242                         return ret;
243
244                 edata->load_count = ((pmcnt3_high << 8) | pmcnt3_low);
245                 break;
246         default:
247                 return -EINVAL;
248         }
249
250         /* Disable specific counter */
251         ret = regmap_read(info->regmap, PPMU_CNTENC, &cntenc);
252         if (ret < 0)
253                 return ret;
254
255         cntenc |= (PPMU_CCNT_MASK | (PPMU_ENABLE << id));
256         ret = regmap_write(info->regmap, PPMU_CNTENC, cntenc);
257         if (ret < 0)
258                 return ret;
259
260         dev_dbg(&edev->dev, "%s (event: %ld/%ld)\n", edev->desc->name,
261                                         edata->load_count, edata->total_count);
262
263         return 0;
264 }
265
266 static const struct devfreq_event_ops exynos_ppmu_ops = {
267         .disable = exynos_ppmu_disable,
268         .set_event = exynos_ppmu_set_event,
269         .get_event = exynos_ppmu_get_event,
270 };
271
272 /*
273  * The devfreq-event ops structure for PPMU v2.0
274  */
275 static int exynos_ppmu_v2_disable(struct devfreq_event_dev *edev)
276 {
277         struct exynos_ppmu *info = devfreq_event_get_drvdata(edev);
278         int ret;
279         u32 pmnc, clear;
280
281         /* Disable all counters */
282         clear = (PPMU_CCNT_MASK | PPMU_PMCNT0_MASK | PPMU_PMCNT1_MASK
283                 | PPMU_PMCNT2_MASK | PPMU_PMCNT3_MASK);
284         ret = regmap_write(info->regmap, PPMU_V2_FLAG, clear);
285         if (ret < 0)
286                 return ret;
287
288         ret = regmap_write(info->regmap, PPMU_V2_INTENC, clear);
289         if (ret < 0)
290                 return ret;
291
292         ret = regmap_write(info->regmap, PPMU_V2_CNTENC, clear);
293         if (ret < 0)
294                 return ret;
295
296         ret = regmap_write(info->regmap, PPMU_V2_CNT_RESET, clear);
297         if (ret < 0)
298                 return ret;
299
300         ret = regmap_write(info->regmap, PPMU_V2_CIG_CFG0, 0x0);
301         if (ret < 0)
302                 return ret;
303
304         ret = regmap_write(info->regmap, PPMU_V2_CIG_CFG1, 0x0);
305         if (ret < 0)
306                 return ret;
307
308         ret = regmap_write(info->regmap, PPMU_V2_CIG_CFG2, 0x0);
309         if (ret < 0)
310                 return ret;
311
312         ret = regmap_write(info->regmap, PPMU_V2_CIG_RESULT, 0x0);
313         if (ret < 0)
314                 return ret;
315
316         ret = regmap_write(info->regmap, PPMU_V2_CNT_AUTO, 0x0);
317         if (ret < 0)
318                 return ret;
319
320         ret = regmap_write(info->regmap, PPMU_V2_CH_EV0_TYPE, 0x0);
321         if (ret < 0)
322                 return ret;
323
324         ret = regmap_write(info->regmap, PPMU_V2_CH_EV1_TYPE, 0x0);
325         if (ret < 0)
326                 return ret;
327
328         ret = regmap_write(info->regmap, PPMU_V2_CH_EV2_TYPE, 0x0);
329         if (ret < 0)
330                 return ret;
331
332         ret = regmap_write(info->regmap, PPMU_V2_CH_EV3_TYPE, 0x0);
333         if (ret < 0)
334                 return ret;
335
336         ret = regmap_write(info->regmap, PPMU_V2_SM_ID_V, 0x0);
337         if (ret < 0)
338                 return ret;
339
340         ret = regmap_write(info->regmap, PPMU_V2_SM_ID_A, 0x0);
341         if (ret < 0)
342                 return ret;
343
344         ret = regmap_write(info->regmap, PPMU_V2_SM_OTHERS_V, 0x0);
345         if (ret < 0)
346                 return ret;
347
348         ret = regmap_write(info->regmap, PPMU_V2_SM_OTHERS_A, 0x0);
349         if (ret < 0)
350                 return ret;
351
352         ret = regmap_write(info->regmap, PPMU_V2_INTERRUPT_RESET, 0x0);
353         if (ret < 0)
354                 return ret;
355
356         /* Disable PPMU */
357         ret = regmap_read(info->regmap, PPMU_V2_PMNC, &pmnc);
358         if (ret < 0)
359                 return ret;
360
361         pmnc &= ~PPMU_PMNC_ENABLE_MASK;
362         ret = regmap_write(info->regmap, PPMU_V2_PMNC, pmnc);
363         if (ret < 0)
364                 return ret;
365
366         return 0;
367 }
368
369 static int exynos_ppmu_v2_set_event(struct devfreq_event_dev *edev)
370 {
371         struct exynos_ppmu *info = devfreq_event_get_drvdata(edev);
372         unsigned int pmnc, cntens;
373         int id = exynos_ppmu_find_ppmu_id(edev);
374         int ret;
375
376         /* Enable all counters */
377         ret = regmap_read(info->regmap, PPMU_V2_CNTENS, &cntens);
378         if (ret < 0)
379                 return ret;
380
381         cntens |= (PPMU_CCNT_MASK | (PPMU_ENABLE << id));
382         ret = regmap_write(info->regmap, PPMU_V2_CNTENS, cntens);
383         if (ret < 0)
384                 return ret;
385
386         /* Set the event of proper data type monitoring */
387         ret = regmap_write(info->regmap, PPMU_V2_CH_EVx_TYPE(id),
388                            edev->desc->event_type);
389         if (ret < 0)
390                 return ret;
391
392         /* Reset cycle counter/performance counter and enable PPMU */
393         ret = regmap_read(info->regmap, PPMU_V2_PMNC, &pmnc);
394         if (ret < 0)
395                 return ret;
396
397         pmnc &= ~(PPMU_PMNC_ENABLE_MASK
398                         | PPMU_PMNC_COUNTER_RESET_MASK
399                         | PPMU_PMNC_CC_RESET_MASK
400                         | PPMU_PMNC_CC_DIVIDER_MASK
401                         | PPMU_V2_PMNC_START_MODE_MASK);
402         pmnc |= (PPMU_ENABLE << PPMU_PMNC_ENABLE_SHIFT);
403         pmnc |= (PPMU_ENABLE << PPMU_PMNC_COUNTER_RESET_SHIFT);
404         pmnc |= (PPMU_ENABLE << PPMU_PMNC_CC_RESET_SHIFT);
405         pmnc |= (PPMU_V2_MODE_MANUAL << PPMU_V2_PMNC_START_MODE_SHIFT);
406
407         ret = regmap_write(info->regmap, PPMU_V2_PMNC, pmnc);
408         if (ret < 0)
409                 return ret;
410
411         return 0;
412 }
413
414 static int exynos_ppmu_v2_get_event(struct devfreq_event_dev *edev,
415                                     struct devfreq_event_data *edata)
416 {
417         struct exynos_ppmu *info = devfreq_event_get_drvdata(edev);
418         int id = exynos_ppmu_find_ppmu_id(edev);
419         int ret;
420         unsigned int pmnc, cntenc;
421         unsigned int pmcnt_high, pmcnt_low;
422         unsigned int total_count, count;
423         unsigned long load_count = 0;
424
425         /* Disable PPMU */
426         ret = regmap_read(info->regmap, PPMU_V2_PMNC, &pmnc);
427         if (ret < 0)
428                 return ret;
429
430         pmnc &= ~PPMU_PMNC_ENABLE_MASK;
431         ret = regmap_write(info->regmap, PPMU_V2_PMNC, pmnc);
432         if (ret < 0)
433                 return ret;
434
435         /* Read cycle count and performance count */
436         ret = regmap_read(info->regmap, PPMU_V2_CCNT, &total_count);
437         if (ret < 0)
438                 return ret;
439         edata->total_count = total_count;
440
441         switch (id) {
442         case PPMU_PMNCNT0:
443         case PPMU_PMNCNT1:
444         case PPMU_PMNCNT2:
445                 ret = regmap_read(info->regmap, PPMU_V2_PMNCT(id), &count);
446                 if (ret < 0)
447                         return ret;
448                 load_count = count;
449                 break;
450         case PPMU_PMNCNT3:
451                 ret = regmap_read(info->regmap, PPMU_V2_PMCNT3_HIGH,
452                                                 &pmcnt_high);
453                 if (ret < 0)
454                         return ret;
455
456                 ret = regmap_read(info->regmap, PPMU_V2_PMCNT3_LOW, &pmcnt_low);
457                 if (ret < 0)
458                         return ret;
459
460                 load_count = ((u64)((pmcnt_high & 0xff)) << 32)+ (u64)pmcnt_low;
461                 break;
462         }
463         edata->load_count = load_count;
464
465         /* Disable all counters */
466         ret = regmap_read(info->regmap, PPMU_V2_CNTENC, &cntenc);
467         if (ret < 0)
468                 return 0;
469
470         cntenc |= (PPMU_CCNT_MASK | (PPMU_ENABLE << id));
471         ret = regmap_write(info->regmap, PPMU_V2_CNTENC, cntenc);
472         if (ret < 0)
473                 return ret;
474
475         dev_dbg(&edev->dev, "%25s (load: %ld / %ld)\n", edev->desc->name,
476                                         edata->load_count, edata->total_count);
477         return 0;
478 }
479
480 static const struct devfreq_event_ops exynos_ppmu_v2_ops = {
481         .disable = exynos_ppmu_v2_disable,
482         .set_event = exynos_ppmu_v2_set_event,
483         .get_event = exynos_ppmu_v2_get_event,
484 };
485
486 static const struct of_device_id exynos_ppmu_id_match[] = {
487         {
488                 .compatible = "samsung,exynos-ppmu",
489                 .data = (void *)EXYNOS_TYPE_PPMU,
490         }, {
491                 .compatible = "samsung,exynos-ppmu-v2",
492                 .data = (void *)EXYNOS_TYPE_PPMU_V2,
493         },
494         { /* sentinel */ },
495 };
496 MODULE_DEVICE_TABLE(of, exynos_ppmu_id_match);
497
498 static int of_get_devfreq_events(struct device_node *np,
499                                  struct exynos_ppmu *info)
500 {
501         struct devfreq_event_desc *desc;
502         struct device *dev = info->dev;
503         struct device_node *events_np, *node;
504         int i, j, count;
505         const struct of_device_id *of_id;
506         int ret;
507
508         events_np = of_get_child_by_name(np, "events");
509         if (!events_np) {
510                 dev_err(dev,
511                         "failed to get child node of devfreq-event devices\n");
512                 return -EINVAL;
513         }
514
515         count = of_get_child_count(events_np);
516         desc = devm_kcalloc(dev, count, sizeof(*desc), GFP_KERNEL);
517         if (!desc)
518                 return -ENOMEM;
519         info->num_events = count;
520
521         of_id = of_match_device(exynos_ppmu_id_match, dev);
522         if (of_id)
523                 info->ppmu_type = (enum exynos_ppmu_type)of_id->data;
524         else
525                 return -EINVAL;
526
527         j = 0;
528         for_each_child_of_node(events_np, node) {
529                 for (i = 0; i < ARRAY_SIZE(ppmu_events); i++) {
530                         if (!ppmu_events[i].name)
531                                 continue;
532
533                         if (of_node_name_eq(node, ppmu_events[i].name))
534                                 break;
535                 }
536
537                 if (i == ARRAY_SIZE(ppmu_events)) {
538                         dev_warn(dev,
539                                 "don't know how to configure events : %pOFn\n",
540                                 node);
541                         continue;
542                 }
543
544                 switch (info->ppmu_type) {
545                 case EXYNOS_TYPE_PPMU:
546                         desc[j].ops = &exynos_ppmu_ops;
547                         break;
548                 case EXYNOS_TYPE_PPMU_V2:
549                         desc[j].ops = &exynos_ppmu_v2_ops;
550                         break;
551                 }
552
553                 desc[j].driver_data = info;
554
555                 of_property_read_string(node, "event-name", &desc[j].name);
556                 ret = of_property_read_u32(node, "event-data-type",
557                                            &desc[j].event_type);
558                 if (ret) {
559                         /* Set the event of proper data type counting.
560                          * Check if the data type has been defined in DT,
561                          * use default if not.
562                          */
563                         if (info->ppmu_type == EXYNOS_TYPE_PPMU_V2) {
564                                 int id;
565                                 /* Not all registers take the same value for
566                                  * read+write data count.
567                                  */
568                                 id = __exynos_ppmu_find_ppmu_id(desc[j].name);
569
570                                 switch (id) {
571                                 case PPMU_PMNCNT0:
572                                 case PPMU_PMNCNT1:
573                                 case PPMU_PMNCNT2:
574                                         desc[j].event_type = PPMU_V2_RO_DATA_CNT
575                                                 | PPMU_V2_WO_DATA_CNT;
576                                         break;
577                                 case PPMU_PMNCNT3:
578                                         desc[j].event_type =
579                                                 PPMU_V2_EVT3_RW_DATA_CNT;
580                                         break;
581                                 }
582                         } else {
583                                 desc[j].event_type = PPMU_RO_DATA_CNT |
584                                         PPMU_WO_DATA_CNT;
585                         }
586                 }
587
588                 j++;
589         }
590         info->desc = desc;
591
592         of_node_put(events_np);
593
594         return 0;
595 }
596
597 static struct regmap_config exynos_ppmu_regmap_config = {
598         .reg_bits = 32,
599         .val_bits = 32,
600         .reg_stride = 4,
601 };
602
603 static int exynos_ppmu_parse_dt(struct platform_device *pdev,
604                                 struct exynos_ppmu *info)
605 {
606         struct device *dev = info->dev;
607         struct device_node *np = dev->of_node;
608         struct resource *res;
609         void __iomem *base;
610         int ret = 0;
611
612         if (!np) {
613                 dev_err(dev, "failed to find devicetree node\n");
614                 return -EINVAL;
615         }
616
617         /* Maps the memory mapped IO to control PPMU register */
618         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
619         base = devm_ioremap_resource(dev, res);
620         if (IS_ERR(base))
621                 return PTR_ERR(base);
622
623         exynos_ppmu_regmap_config.max_register = resource_size(res) - 4;
624         info->regmap = devm_regmap_init_mmio(dev, base,
625                                         &exynos_ppmu_regmap_config);
626         if (IS_ERR(info->regmap)) {
627                 dev_err(dev, "failed to initialize regmap\n");
628                 return PTR_ERR(info->regmap);
629         }
630
631         info->ppmu.clk = devm_clk_get(dev, "ppmu");
632         if (IS_ERR(info->ppmu.clk)) {
633                 info->ppmu.clk = NULL;
634                 dev_warn(dev, "cannot get PPMU clock\n");
635         }
636
637         ret = of_get_devfreq_events(np, info);
638         if (ret < 0) {
639                 dev_err(dev, "failed to parse exynos ppmu dt node\n");
640                 return ret;
641         }
642
643         return 0;
644 }
645
646 static int exynos_ppmu_probe(struct platform_device *pdev)
647 {
648         struct exynos_ppmu *info;
649         struct devfreq_event_dev **edev;
650         struct devfreq_event_desc *desc;
651         int i, ret = 0, size;
652
653         info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
654         if (!info)
655                 return -ENOMEM;
656
657         info->dev = &pdev->dev;
658
659         /* Parse dt data to get resource */
660         ret = exynos_ppmu_parse_dt(pdev, info);
661         if (ret < 0) {
662                 dev_err(&pdev->dev,
663                         "failed to parse devicetree for resource\n");
664                 return ret;
665         }
666         desc = info->desc;
667
668         size = sizeof(struct devfreq_event_dev *) * info->num_events;
669         info->edev = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
670         if (!info->edev)
671                 return -ENOMEM;
672
673         edev = info->edev;
674         platform_set_drvdata(pdev, info);
675
676         for (i = 0; i < info->num_events; i++) {
677                 edev[i] = devm_devfreq_event_add_edev(&pdev->dev, &desc[i]);
678                 if (IS_ERR(edev[i])) {
679                         dev_err(&pdev->dev,
680                                 "failed to add devfreq-event device\n");
681                         return PTR_ERR(edev[i]);
682                 }
683
684                 pr_info("exynos-ppmu: new PPMU device registered %s (%s)\n",
685                         dev_name(&pdev->dev), desc[i].name);
686         }
687
688         ret = clk_prepare_enable(info->ppmu.clk);
689         if (ret) {
690                 dev_err(&pdev->dev, "failed to prepare ppmu clock\n");
691                 return ret;
692         }
693
694         return 0;
695 }
696
697 static int exynos_ppmu_remove(struct platform_device *pdev)
698 {
699         struct exynos_ppmu *info = platform_get_drvdata(pdev);
700
701         clk_disable_unprepare(info->ppmu.clk);
702
703         return 0;
704 }
705
706 static struct platform_driver exynos_ppmu_driver = {
707         .probe  = exynos_ppmu_probe,
708         .remove = exynos_ppmu_remove,
709         .driver = {
710                 .name   = "exynos-ppmu",
711                 .of_match_table = exynos_ppmu_id_match,
712         },
713 };
714 module_platform_driver(exynos_ppmu_driver);
715
716 MODULE_DESCRIPTION("Exynos PPMU(Platform Performance Monitoring Unit) driver");
717 MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
718 MODULE_LICENSE("GPL");