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");
719