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  1// SPDX-License-Identifier: GPL-2.0+
  2//
  3// Linux performance counter support for ARC CPUs.
  4// This code is inspired by the perf support of various other architectures.
  5//
  6// Copyright (C) 2013-2018 Synopsys, Inc. (www.synopsys.com)
  7
  8#include <linux/errno.h>
  9#include <linux/interrupt.h>
 10#include <linux/module.h>
 11#include <linux/of.h>
 12#include <linux/perf_event.h>
 13#include <linux/platform_device.h>
 14#include <asm/arcregs.h>
 15#include <asm/stacktrace.h>
 16
 17/* HW holds 8 symbols + one for null terminator */
 18#define ARCPMU_EVENT_NAME_LEN	9
 19
 20enum arc_pmu_attr_groups {
 21	ARCPMU_ATTR_GR_EVENTS,
 22	ARCPMU_ATTR_GR_FORMATS,
 23	ARCPMU_NR_ATTR_GR
 24};
 25
 26struct arc_pmu_raw_event_entry {
 27	char name[ARCPMU_EVENT_NAME_LEN];
 28};
 29
 30struct arc_pmu {
 31	struct pmu	pmu;
 32	unsigned int	irq;
 33	int		n_counters;
 34	int		n_events;
 35	u64		max_period;
 36	int		ev_hw_idx[PERF_COUNT_ARC_HW_MAX];
 37
 38	struct arc_pmu_raw_event_entry	*raw_entry;
 39	struct attribute		**attrs;
 40	struct perf_pmu_events_attr	*attr;
 41	const struct attribute_group	*attr_groups[ARCPMU_NR_ATTR_GR + 1];
 42};
 43
 44struct arc_pmu_cpu {
 45	/*
 46	 * A 1 bit for an index indicates that the counter is being used for
 47	 * an event. A 0 means that the counter can be used.
 48	 */
 49	unsigned long	used_mask[BITS_TO_LONGS(ARC_PERF_MAX_COUNTERS)];
 50
 51	/*
 52	 * The events that are active on the PMU for the given index.
 53	 */
 54	struct perf_event *act_counter[ARC_PERF_MAX_COUNTERS];
 55};
 56
 57struct arc_callchain_trace {
 58	int depth;
 59	void *perf_stuff;
 60};
 61
 62static int callchain_trace(unsigned int addr, void *data)
 63{
 64	struct arc_callchain_trace *ctrl = data;
 65	struct perf_callchain_entry_ctx *entry = ctrl->perf_stuff;
 66
 67	perf_callchain_store(entry, addr);
 68
 69	if (ctrl->depth++ < 3)
 70		return 0;
 71
 72	return -1;
 73}
 74
 75void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry,
 76			   struct pt_regs *regs)
 77{
 78	struct arc_callchain_trace ctrl = {
 79		.depth = 0,
 80		.perf_stuff = entry,
 81	};
 82
 83	arc_unwind_core(NULL, regs, callchain_trace, &ctrl);
 84}
 85
 86void perf_callchain_user(struct perf_callchain_entry_ctx *entry,
 87			 struct pt_regs *regs)
 88{
 89	/*
 90	 * User stack can't be unwound trivially with kernel dwarf unwinder
 91	 * So for now just record the user PC
 92	 */
 93	perf_callchain_store(entry, instruction_pointer(regs));
 94}
 95
 96static struct arc_pmu *arc_pmu;
 97static DEFINE_PER_CPU(struct arc_pmu_cpu, arc_pmu_cpu);
 98
 99/* read counter #idx; note that counter# != event# on ARC! */
100static u64 arc_pmu_read_counter(int idx)
101{
102	u32 tmp;
103	u64 result;
104
105	/*
106	 * ARC supports making 'snapshots' of the counters, so we don't
107	 * need to care about counters wrapping to 0 underneath our feet
108	 */
109	write_aux_reg(ARC_REG_PCT_INDEX, idx);
110	tmp = read_aux_reg(ARC_REG_PCT_CONTROL);
111	write_aux_reg(ARC_REG_PCT_CONTROL, tmp | ARC_REG_PCT_CONTROL_SN);
112	result = (u64) (read_aux_reg(ARC_REG_PCT_SNAPH)) << 32;
113	result |= read_aux_reg(ARC_REG_PCT_SNAPL);
114
115	return result;
116}
117
118static void arc_perf_event_update(struct perf_event *event,
119				  struct hw_perf_event *hwc, int idx)
120{
121	u64 prev_raw_count = local64_read(&hwc->prev_count);
122	u64 new_raw_count = arc_pmu_read_counter(idx);
123	s64 delta = new_raw_count - prev_raw_count;
124
125	/*
126	 * We aren't afraid of hwc->prev_count changing beneath our feet
127	 * because there's no way for us to re-enter this function anytime.
128	 */
129	local64_set(&hwc->prev_count, new_raw_count);
130	local64_add(delta, &event->count);
131	local64_sub(delta, &hwc->period_left);
132}
133
134static void arc_pmu_read(struct perf_event *event)
135{
136	arc_perf_event_update(event, &event->hw, event->hw.idx);
137}
138
139static int arc_pmu_cache_event(u64 config)
140{
141	unsigned int cache_type, cache_op, cache_result;
142	int ret;
143
144	cache_type	= (config >>  0) & 0xff;
145	cache_op	= (config >>  8) & 0xff;
146	cache_result	= (config >> 16) & 0xff;
147	if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
148		return -EINVAL;
149	if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
150		return -EINVAL;
151	if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
152		return -EINVAL;
153
154	ret = arc_pmu_cache_map[cache_type][cache_op][cache_result];
155
156	if (ret == CACHE_OP_UNSUPPORTED)
157		return -ENOENT;
158
159	pr_debug("init cache event: type/op/result %d/%d/%d with h/w %d \'%s\'\n",
160		 cache_type, cache_op, cache_result, ret,
161		 arc_pmu_ev_hw_map[ret]);
162
163	return ret;
164}
165
166/* initializes hw_perf_event structure if event is supported */
167static int arc_pmu_event_init(struct perf_event *event)
168{
169	struct hw_perf_event *hwc = &event->hw;
170	int ret;
171
172	if (!is_sampling_event(event)) {
173		hwc->sample_period = arc_pmu->max_period;
174		hwc->last_period = hwc->sample_period;
175		local64_set(&hwc->period_left, hwc->sample_period);
176	}
177
178	hwc->config = 0;
179
180	if (is_isa_arcv2()) {
181		/* "exclude user" means "count only kernel" */
182		if (event->attr.exclude_user)
183			hwc->config |= ARC_REG_PCT_CONFIG_KERN;
184
185		/* "exclude kernel" means "count only user" */
186		if (event->attr.exclude_kernel)
187			hwc->config |= ARC_REG_PCT_CONFIG_USER;
188	}
189
190	switch (event->attr.type) {
191	case PERF_TYPE_HARDWARE:
192		if (event->attr.config >= PERF_COUNT_HW_MAX)
193			return -ENOENT;
194		if (arc_pmu->ev_hw_idx[event->attr.config] < 0)
195			return -ENOENT;
196		hwc->config |= arc_pmu->ev_hw_idx[event->attr.config];
197		pr_debug("init event %d with h/w %08x \'%s\'\n",
198			 (int)event->attr.config, (int)hwc->config,
199			 arc_pmu_ev_hw_map[event->attr.config]);
200		return 0;
201
202	case PERF_TYPE_HW_CACHE:
203		ret = arc_pmu_cache_event(event->attr.config);
204		if (ret < 0)
205			return ret;
206		hwc->config |= arc_pmu->ev_hw_idx[ret];
207		pr_debug("init cache event with h/w %08x \'%s\'\n",
208			 (int)hwc->config, arc_pmu_ev_hw_map[ret]);
209		return 0;
210
211	case PERF_TYPE_RAW:
212		if (event->attr.config >= arc_pmu->n_events)
213			return -ENOENT;
214
215		hwc->config |= event->attr.config;
216		pr_debug("init raw event with idx %lld \'%s\'\n",
217			 event->attr.config,
218			 arc_pmu->raw_entry[event->attr.config].name);
219
220		return 0;
221
222	default:
223		return -ENOENT;
224	}
225}
226
227/* starts all counters */
228static void arc_pmu_enable(struct pmu *pmu)
229{
230	u32 tmp;
231	tmp = read_aux_reg(ARC_REG_PCT_CONTROL);
232	write_aux_reg(ARC_REG_PCT_CONTROL, (tmp & 0xffff0000) | 0x1);
233}
234
235/* stops all counters */
236static void arc_pmu_disable(struct pmu *pmu)
237{
238	u32 tmp;
239	tmp = read_aux_reg(ARC_REG_PCT_CONTROL);
240	write_aux_reg(ARC_REG_PCT_CONTROL, (tmp & 0xffff0000) | 0x0);
241}
242
243static int arc_pmu_event_set_period(struct perf_event *event)
244{
245	struct hw_perf_event *hwc = &event->hw;
246	s64 left = local64_read(&hwc->period_left);
247	s64 period = hwc->sample_period;
248	int idx = hwc->idx;
249	int overflow = 0;
250	u64 value;
251
252	if (unlikely(left <= -period)) {
253		/* left underflowed by more than period. */
254		left = period;
255		local64_set(&hwc->period_left, left);
256		hwc->last_period = period;
257		overflow = 1;
258	} else if (unlikely(left <= 0)) {
259		/* left underflowed by less than period. */
260		left += period;
261		local64_set(&hwc->period_left, left);
262		hwc->last_period = period;
263		overflow = 1;
264	}
265
266	if (left > arc_pmu->max_period)
267		left = arc_pmu->max_period;
268
269	value = arc_pmu->max_period - left;
270	local64_set(&hwc->prev_count, value);
271
272	/* Select counter */
273	write_aux_reg(ARC_REG_PCT_INDEX, idx);
274
275	/* Write value */
276	write_aux_reg(ARC_REG_PCT_COUNTL, lower_32_bits(value));
277	write_aux_reg(ARC_REG_PCT_COUNTH, upper_32_bits(value));
278
279	perf_event_update_userpage(event);
280
281	return overflow;
282}
283
284/*
285 * Assigns hardware counter to hardware condition.
286 * Note that there is no separate start/stop mechanism;
287 * stopping is achieved by assigning the 'never' condition
288 */
289static void arc_pmu_start(struct perf_event *event, int flags)
290{
291	struct hw_perf_event *hwc = &event->hw;
292	int idx = hwc->idx;
293
294	if (WARN_ON_ONCE(idx == -1))
295		return;
296
297	if (flags & PERF_EF_RELOAD)
298		WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
299
300	hwc->state = 0;
301
302	arc_pmu_event_set_period(event);
303
304	/* Enable interrupt for this counter */
305	if (is_sampling_event(event))
306		write_aux_reg(ARC_REG_PCT_INT_CTRL,
307			      read_aux_reg(ARC_REG_PCT_INT_CTRL) | BIT(idx));
308
309	/* enable ARC pmu here */
310	write_aux_reg(ARC_REG_PCT_INDEX, idx);		/* counter # */
311	write_aux_reg(ARC_REG_PCT_CONFIG, hwc->config);	/* condition */
312}
313
314static void arc_pmu_stop(struct perf_event *event, int flags)
315{
316	struct hw_perf_event *hwc = &event->hw;
317	int idx = hwc->idx;
318
319	/* Disable interrupt for this counter */
320	if (is_sampling_event(event)) {
321		/*
322		 * Reset interrupt flag by writing of 1. This is required
323		 * to make sure pending interrupt was not left.
324		 */
325		write_aux_reg(ARC_REG_PCT_INT_ACT, BIT(idx));
326		write_aux_reg(ARC_REG_PCT_INT_CTRL,
327			      read_aux_reg(ARC_REG_PCT_INT_CTRL) & ~BIT(idx));
328	}
329
330	if (!(event->hw.state & PERF_HES_STOPPED)) {
331		/* stop ARC pmu here */
332		write_aux_reg(ARC_REG_PCT_INDEX, idx);
333
334		/* condition code #0 is always "never" */
335		write_aux_reg(ARC_REG_PCT_CONFIG, 0);
336
337		event->hw.state |= PERF_HES_STOPPED;
338	}
339
340	if ((flags & PERF_EF_UPDATE) &&
341	    !(event->hw.state & PERF_HES_UPTODATE)) {
342		arc_perf_event_update(event, &event->hw, idx);
343		event->hw.state |= PERF_HES_UPTODATE;
344	}
345}
346
347static void arc_pmu_del(struct perf_event *event, int flags)
348{
349	struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu);
350
351	arc_pmu_stop(event, PERF_EF_UPDATE);
352	__clear_bit(event->hw.idx, pmu_cpu->used_mask);
353
354	pmu_cpu->act_counter[event->hw.idx] = 0;
355
356	perf_event_update_userpage(event);
357}
358
359/* allocate hardware counter and optionally start counting */
360static int arc_pmu_add(struct perf_event *event, int flags)
361{
362	struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu);
363	struct hw_perf_event *hwc = &event->hw;
364	int idx = hwc->idx;
365
366	idx = ffz(pmu_cpu->used_mask[0]);
367	if (idx == arc_pmu->n_counters)
368		return -EAGAIN;
369
370	__set_bit(idx, pmu_cpu->used_mask);
371	hwc->idx = idx;
372
373	write_aux_reg(ARC_REG_PCT_INDEX, idx);
374
375	pmu_cpu->act_counter[idx] = event;
376
377	if (is_sampling_event(event)) {
378		/* Mimic full counter overflow as other arches do */
379		write_aux_reg(ARC_REG_PCT_INT_CNTL,
380			      lower_32_bits(arc_pmu->max_period));
381		write_aux_reg(ARC_REG_PCT_INT_CNTH,
382			      upper_32_bits(arc_pmu->max_period));
383	}
384
385	write_aux_reg(ARC_REG_PCT_CONFIG, 0);
386	write_aux_reg(ARC_REG_PCT_COUNTL, 0);
387	write_aux_reg(ARC_REG_PCT_COUNTH, 0);
388	local64_set(&hwc->prev_count, 0);
389
390	hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
391	if (flags & PERF_EF_START)
392		arc_pmu_start(event, PERF_EF_RELOAD);
393
394	perf_event_update_userpage(event);
395
396	return 0;
397}
398
399#ifdef CONFIG_ISA_ARCV2
400static irqreturn_t arc_pmu_intr(int irq, void *dev)
401{
402	struct perf_sample_data data;
403	struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu);
404	struct pt_regs *regs;
405	unsigned int active_ints;
406	int idx;
407
408	arc_pmu_disable(&arc_pmu->pmu);
409
410	active_ints = read_aux_reg(ARC_REG_PCT_INT_ACT);
411	if (!active_ints)
412		goto done;
413
414	regs = get_irq_regs();
415
416	do {
417		struct perf_event *event;
418		struct hw_perf_event *hwc;
419
420		idx = __ffs(active_ints);
421
422		/* Reset interrupt flag by writing of 1 */
423		write_aux_reg(ARC_REG_PCT_INT_ACT, BIT(idx));
424
425		/*
426		 * On reset of "interrupt active" bit corresponding
427		 * "interrupt enable" bit gets automatically reset as well.
428		 * Now we need to re-enable interrupt for the counter.
429		 */
430		write_aux_reg(ARC_REG_PCT_INT_CTRL,
431			read_aux_reg(ARC_REG_PCT_INT_CTRL) | BIT(idx));
432
433		event = pmu_cpu->act_counter[idx];
434		hwc = &event->hw;
435
436		WARN_ON_ONCE(hwc->idx != idx);
437
438		arc_perf_event_update(event, &event->hw, event->hw.idx);
439		perf_sample_data_init(&data, 0, hwc->last_period);
440		if (arc_pmu_event_set_period(event)) {
441			if (perf_event_overflow(event, &data, regs))
442				arc_pmu_stop(event, 0);
443		}
444
445		active_ints &= ~BIT(idx);
446	} while (active_ints);
447
448done:
449	arc_pmu_enable(&arc_pmu->pmu);
450
451	return IRQ_HANDLED;
452}
453#else
454
455static irqreturn_t arc_pmu_intr(int irq, void *dev)
456{
457	return IRQ_NONE;
458}
459
460#endif /* CONFIG_ISA_ARCV2 */
461
462static void arc_cpu_pmu_irq_init(void *data)
463{
464	int irq = *(int *)data;
465
466	enable_percpu_irq(irq, IRQ_TYPE_NONE);
467
468	/* Clear all pending interrupt flags */
469	write_aux_reg(ARC_REG_PCT_INT_ACT, 0xffffffff);
470}
471
472/* Event field occupies the bottom 15 bits of our config field */
473PMU_FORMAT_ATTR(event, "config:0-14");
474static struct attribute *arc_pmu_format_attrs[] = {
475	&format_attr_event.attr,
476	NULL,
477};
478
479static struct attribute_group arc_pmu_format_attr_gr = {
480	.name = "format",
481	.attrs = arc_pmu_format_attrs,
482};
483
484static ssize_t arc_pmu_events_sysfs_show(struct device *dev,
485					 struct device_attribute *attr,
486					 char *page)
487{
488	struct perf_pmu_events_attr *pmu_attr;
489
490	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
491	return sprintf(page, "event=0x%04llx\n", pmu_attr->id);
492}
493
494/*
495 * We don't add attrs here as we don't have pre-defined list of perf events.
496 * We will generate and add attrs dynamically in probe() after we read HW
497 * configuration.
498 */
499static struct attribute_group arc_pmu_events_attr_gr = {
500	.name = "events",
501};
502
503static void arc_pmu_add_raw_event_attr(int j, char *str)
504{
505	memmove(arc_pmu->raw_entry[j].name, str, ARCPMU_EVENT_NAME_LEN - 1);
506	arc_pmu->attr[j].attr.attr.name = arc_pmu->raw_entry[j].name;
507	arc_pmu->attr[j].attr.attr.mode = VERIFY_OCTAL_PERMISSIONS(0444);
508	arc_pmu->attr[j].attr.show = arc_pmu_events_sysfs_show;
509	arc_pmu->attr[j].id = j;
510	arc_pmu->attrs[j] = &(arc_pmu->attr[j].attr.attr);
511}
512
513static int arc_pmu_raw_alloc(struct device *dev)
514{
515	arc_pmu->attr = devm_kmalloc_array(dev, arc_pmu->n_events + 1,
516		sizeof(*arc_pmu->attr), GFP_KERNEL | __GFP_ZERO);
517	if (!arc_pmu->attr)
518		return -ENOMEM;
519
520	arc_pmu->attrs = devm_kmalloc_array(dev, arc_pmu->n_events + 1,
521		sizeof(*arc_pmu->attrs), GFP_KERNEL | __GFP_ZERO);
522	if (!arc_pmu->attrs)
523		return -ENOMEM;
524
525	arc_pmu->raw_entry = devm_kmalloc_array(dev, arc_pmu->n_events,
526		sizeof(*arc_pmu->raw_entry), GFP_KERNEL | __GFP_ZERO);
527	if (!arc_pmu->raw_entry)
528		return -ENOMEM;
529
530	return 0;
531}
532
533static inline bool event_in_hw_event_map(int i, char *name)
534{
535	if (!arc_pmu_ev_hw_map[i])
536		return false;
537
538	if (!strlen(arc_pmu_ev_hw_map[i]))
539		return false;
540
541	if (strcmp(arc_pmu_ev_hw_map[i], name))
542		return false;
543
544	return true;
545}
546
547static void arc_pmu_map_hw_event(int j, char *str)
548{
549	int i;
550
551	/* See if HW condition has been mapped to a perf event_id */
552	for (i = 0; i < ARRAY_SIZE(arc_pmu_ev_hw_map); i++) {
553		if (event_in_hw_event_map(i, str)) {
554			pr_debug("mapping perf event %2d to h/w event \'%8s\' (idx %d)\n",
555				 i, str, j);
556			arc_pmu->ev_hw_idx[i] = j;
557		}
558	}
559}
560
561static int arc_pmu_device_probe(struct platform_device *pdev)
562{
563	struct arc_reg_pct_build pct_bcr;
564	struct arc_reg_cc_build cc_bcr;
565	int i, has_interrupts, irq;
566	int counter_size;	/* in bits */
567
568	union cc_name {
569		struct {
570			u32 word0, word1;
571			char sentinel;
572		} indiv;
573		char str[ARCPMU_EVENT_NAME_LEN];
574	} cc_name;
575
576
577	READ_BCR(ARC_REG_PCT_BUILD, pct_bcr);
578	if (!pct_bcr.v) {
579		pr_err("This core does not have performance counters!\n");
580		return -ENODEV;
581	}
582	BUILD_BUG_ON(ARC_PERF_MAX_COUNTERS > 32);
583	if (WARN_ON(pct_bcr.c > ARC_PERF_MAX_COUNTERS))
584		return -EINVAL;
585
586	READ_BCR(ARC_REG_CC_BUILD, cc_bcr);
587	if (WARN(!cc_bcr.v, "Counters exist but No countable conditions?"))
588		return -EINVAL;
589
590	arc_pmu = devm_kzalloc(&pdev->dev, sizeof(struct arc_pmu), GFP_KERNEL);
591	if (!arc_pmu)
592		return -ENOMEM;
593
594	arc_pmu->n_events = cc_bcr.c;
595
596	if (arc_pmu_raw_alloc(&pdev->dev))
597		return -ENOMEM;
598
599	has_interrupts = is_isa_arcv2() ? pct_bcr.i : 0;
600
601	arc_pmu->n_counters = pct_bcr.c;
602	counter_size = 32 + (pct_bcr.s << 4);
603
604	arc_pmu->max_period = (1ULL << counter_size) / 2 - 1ULL;
605
606	pr_info("ARC perf\t: %d counters (%d bits), %d conditions%s\n",
607		arc_pmu->n_counters, counter_size, cc_bcr.c,
608		has_interrupts ? ", [overflow IRQ support]" : "");
609
610	cc_name.str[ARCPMU_EVENT_NAME_LEN - 1] = 0;
611	for (i = 0; i < PERF_COUNT_ARC_HW_MAX; i++)
612		arc_pmu->ev_hw_idx[i] = -1;
613
614	/* loop thru all available h/w condition indexes */
615	for (i = 0; i < cc_bcr.c; i++) {
616		write_aux_reg(ARC_REG_CC_INDEX, i);
617		cc_name.indiv.word0 = le32_to_cpu(read_aux_reg(ARC_REG_CC_NAME0));
618		cc_name.indiv.word1 = le32_to_cpu(read_aux_reg(ARC_REG_CC_NAME1));
619
620		arc_pmu_map_hw_event(i, cc_name.str);
621		arc_pmu_add_raw_event_attr(i, cc_name.str);
622	}
623
624	arc_pmu_events_attr_gr.attrs = arc_pmu->attrs;
625	arc_pmu->attr_groups[ARCPMU_ATTR_GR_EVENTS] = &arc_pmu_events_attr_gr;
626	arc_pmu->attr_groups[ARCPMU_ATTR_GR_FORMATS] = &arc_pmu_format_attr_gr;
627
628	arc_pmu->pmu = (struct pmu) {
629		.pmu_enable	= arc_pmu_enable,
630		.pmu_disable	= arc_pmu_disable,
631		.event_init	= arc_pmu_event_init,
632		.add		= arc_pmu_add,
633		.del		= arc_pmu_del,
634		.start		= arc_pmu_start,
635		.stop		= arc_pmu_stop,
636		.read		= arc_pmu_read,
637		.attr_groups	= arc_pmu->attr_groups,
638	};
639
640	if (has_interrupts && (irq = platform_get_irq(pdev, 0) >= 0)) {
641
642		arc_pmu->irq = irq;
643
644		/* intc map function ensures irq_set_percpu_devid() called */
645		request_percpu_irq(irq, arc_pmu_intr, "ARC perf counters",
646				   this_cpu_ptr(&arc_pmu_cpu));
647
648		on_each_cpu(arc_cpu_pmu_irq_init, &irq, 1);
649	} else {
650		arc_pmu->pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
651	}
652
653	/*
654	 * perf parser doesn't really like '-' symbol in events name, so let's
655	 * use '_' in arc pct name as it goes to kernel PMU event prefix.
656	 */
657	return perf_pmu_register(&arc_pmu->pmu, "arc_pct", PERF_TYPE_RAW);
658}
659
660static const struct of_device_id arc_pmu_match[] = {
661	{ .compatible = "snps,arc700-pct" },
662	{ .compatible = "snps,archs-pct" },
663	{},
664};
665MODULE_DEVICE_TABLE(of, arc_pmu_match);
666
667static struct platform_driver arc_pmu_driver = {
668	.driver	= {
669		.name		= "arc-pct",
670		.of_match_table = of_match_ptr(arc_pmu_match),
671	},
672	.probe		= arc_pmu_device_probe,
673};
674
675module_platform_driver(arc_pmu_driver);
676
677MODULE_LICENSE("GPL");
678MODULE_AUTHOR("Mischa Jonker <mjonker@synopsys.com>");
679MODULE_DESCRIPTION("ARC PMU driver");