1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright 2017 NXP
4  * Copyright 2016 Freescale Semiconductor, Inc.
5  */
6 
7 #include <linux/bitfield.h>
8 #include <linux/init.h>
9 #include <linux/interrupt.h>
10 #include <linux/io.h>
11 #include <linux/module.h>
12 #include <linux/of.h>
13 #include <linux/of_address.h>
14 #include <linux/of_device.h>
15 #include <linux/of_irq.h>
16 #include <linux/perf_event.h>
17 #include <linux/slab.h>
18 
19 #define COUNTER_CNTL		0x0
20 #define COUNTER_READ		0x20
21 
22 #define COUNTER_DPCR1		0x30
23 
24 #define CNTL_OVER		0x1
25 #define CNTL_CLEAR		0x2
26 #define CNTL_EN			0x4
27 #define CNTL_EN_MASK		0xFFFFFFFB
28 #define CNTL_CLEAR_MASK		0xFFFFFFFD
29 #define CNTL_OVER_MASK		0xFFFFFFFE
30 
31 #define CNTL_CSV_SHIFT		24
32 #define CNTL_CSV_MASK		(0xFF << CNTL_CSV_SHIFT)
33 
34 #define EVENT_CYCLES_ID		0
35 #define EVENT_CYCLES_COUNTER	0
36 #define NUM_COUNTERS		4
37 
38 #define AXI_MASKING_REVERT	0xffff0000	/* AXI_MASKING(MSB 16bits) + AXI_ID(LSB 16bits) */
39 
40 #define to_ddr_pmu(p)		container_of(p, struct ddr_pmu, pmu)
41 
42 #define DDR_PERF_DEV_NAME	"imx8_ddr"
43 #define DDR_CPUHP_CB_NAME	DDR_PERF_DEV_NAME "_perf_pmu"
44 
45 static DEFINE_IDA(ddr_ida);
46 
47 /* DDR Perf hardware feature */
48 #define DDR_CAP_AXI_ID_FILTER			0x1     /* support AXI ID filter */
49 #define DDR_CAP_AXI_ID_FILTER_ENHANCED		0x3     /* support enhanced AXI ID filter */
50 
51 struct fsl_ddr_devtype_data {
52 	unsigned int quirks;    /* quirks needed for different DDR Perf core */
53 };
54 
55 static const struct fsl_ddr_devtype_data imx8_devtype_data;
56 
57 static const struct fsl_ddr_devtype_data imx8m_devtype_data = {
58 	.quirks = DDR_CAP_AXI_ID_FILTER,
59 };
60 
61 static const struct fsl_ddr_devtype_data imx8mp_devtype_data = {
62 	.quirks = DDR_CAP_AXI_ID_FILTER_ENHANCED,
63 };
64 
65 static const struct of_device_id imx_ddr_pmu_dt_ids[] = {
66 	{ .compatible = "fsl,imx8-ddr-pmu", .data = &imx8_devtype_data},
67 	{ .compatible = "fsl,imx8m-ddr-pmu", .data = &imx8m_devtype_data},
68 	{ .compatible = "fsl,imx8mp-ddr-pmu", .data = &imx8mp_devtype_data},
69 	{ /* sentinel */ }
70 };
71 MODULE_DEVICE_TABLE(of, imx_ddr_pmu_dt_ids);
72 
73 struct ddr_pmu {
74 	struct pmu pmu;
75 	void __iomem *base;
76 	unsigned int cpu;
77 	struct	hlist_node node;
78 	struct	device *dev;
79 	struct perf_event *events[NUM_COUNTERS];
80 	int active_events;
81 	enum cpuhp_state cpuhp_state;
82 	const struct fsl_ddr_devtype_data *devtype_data;
83 	int irq;
84 	int id;
85 };
86 
87 enum ddr_perf_filter_capabilities {
88 	PERF_CAP_AXI_ID_FILTER = 0,
89 	PERF_CAP_AXI_ID_FILTER_ENHANCED,
90 	PERF_CAP_AXI_ID_FEAT_MAX,
91 };
92 
93 static u32 ddr_perf_filter_cap_get(struct ddr_pmu *pmu, int cap)
94 {
95 	u32 quirks = pmu->devtype_data->quirks;
96 
97 	switch (cap) {
98 	case PERF_CAP_AXI_ID_FILTER:
99 		return !!(quirks & DDR_CAP_AXI_ID_FILTER);
100 	case PERF_CAP_AXI_ID_FILTER_ENHANCED:
101 		quirks &= DDR_CAP_AXI_ID_FILTER_ENHANCED;
102 		return quirks == DDR_CAP_AXI_ID_FILTER_ENHANCED;
103 	default:
104 		WARN(1, "unknown filter cap %d\n", cap);
105 	}
106 
107 	return 0;
108 }
109 
110 static ssize_t ddr_perf_filter_cap_show(struct device *dev,
111 					struct device_attribute *attr,
112 					char *buf)
113 {
114 	struct ddr_pmu *pmu = dev_get_drvdata(dev);
115 	struct dev_ext_attribute *ea =
116 		container_of(attr, struct dev_ext_attribute, attr);
117 	int cap = (long)ea->var;
118 
119 	return snprintf(buf, PAGE_SIZE, "%u\n",
120 			ddr_perf_filter_cap_get(pmu, cap));
121 }
122 
123 #define PERF_EXT_ATTR_ENTRY(_name, _func, _var)				\
124 	(&((struct dev_ext_attribute) {					\
125 		__ATTR(_name, 0444, _func, NULL), (void *)_var		\
126 	}).attr.attr)
127 
128 #define PERF_FILTER_EXT_ATTR_ENTRY(_name, _var)				\
129 	PERF_EXT_ATTR_ENTRY(_name, ddr_perf_filter_cap_show, _var)
130 
131 static struct attribute *ddr_perf_filter_cap_attr[] = {
132 	PERF_FILTER_EXT_ATTR_ENTRY(filter, PERF_CAP_AXI_ID_FILTER),
133 	PERF_FILTER_EXT_ATTR_ENTRY(enhanced_filter, PERF_CAP_AXI_ID_FILTER_ENHANCED),
134 	NULL,
135 };
136 
137 static struct attribute_group ddr_perf_filter_cap_attr_group = {
138 	.name = "caps",
139 	.attrs = ddr_perf_filter_cap_attr,
140 };
141 
142 static ssize_t ddr_perf_cpumask_show(struct device *dev,
143 				struct device_attribute *attr, char *buf)
144 {
145 	struct ddr_pmu *pmu = dev_get_drvdata(dev);
146 
147 	return cpumap_print_to_pagebuf(true, buf, cpumask_of(pmu->cpu));
148 }
149 
150 static struct device_attribute ddr_perf_cpumask_attr =
151 	__ATTR(cpumask, 0444, ddr_perf_cpumask_show, NULL);
152 
153 static struct attribute *ddr_perf_cpumask_attrs[] = {
154 	&ddr_perf_cpumask_attr.attr,
155 	NULL,
156 };
157 
158 static struct attribute_group ddr_perf_cpumask_attr_group = {
159 	.attrs = ddr_perf_cpumask_attrs,
160 };
161 
162 static ssize_t
163 ddr_pmu_event_show(struct device *dev, struct device_attribute *attr,
164 		   char *page)
165 {
166 	struct perf_pmu_events_attr *pmu_attr;
167 
168 	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
169 	return sprintf(page, "event=0x%02llx\n", pmu_attr->id);
170 }
171 
172 #define IMX8_DDR_PMU_EVENT_ATTR(_name, _id)				\
173 	(&((struct perf_pmu_events_attr[]) {				\
174 		{ .attr = __ATTR(_name, 0444, ddr_pmu_event_show, NULL),\
175 		  .id = _id, }						\
176 	})[0].attr.attr)
177 
178 static struct attribute *ddr_perf_events_attrs[] = {
179 	IMX8_DDR_PMU_EVENT_ATTR(cycles, EVENT_CYCLES_ID),
180 	IMX8_DDR_PMU_EVENT_ATTR(selfresh, 0x01),
181 	IMX8_DDR_PMU_EVENT_ATTR(read-accesses, 0x04),
182 	IMX8_DDR_PMU_EVENT_ATTR(write-accesses, 0x05),
183 	IMX8_DDR_PMU_EVENT_ATTR(read-queue-depth, 0x08),
184 	IMX8_DDR_PMU_EVENT_ATTR(write-queue-depth, 0x09),
185 	IMX8_DDR_PMU_EVENT_ATTR(lp-read-credit-cnt, 0x10),
186 	IMX8_DDR_PMU_EVENT_ATTR(hp-read-credit-cnt, 0x11),
187 	IMX8_DDR_PMU_EVENT_ATTR(write-credit-cnt, 0x12),
188 	IMX8_DDR_PMU_EVENT_ATTR(read-command, 0x20),
189 	IMX8_DDR_PMU_EVENT_ATTR(write-command, 0x21),
190 	IMX8_DDR_PMU_EVENT_ATTR(read-modify-write-command, 0x22),
191 	IMX8_DDR_PMU_EVENT_ATTR(hp-read, 0x23),
192 	IMX8_DDR_PMU_EVENT_ATTR(hp-req-nocredit, 0x24),
193 	IMX8_DDR_PMU_EVENT_ATTR(hp-xact-credit, 0x25),
194 	IMX8_DDR_PMU_EVENT_ATTR(lp-req-nocredit, 0x26),
195 	IMX8_DDR_PMU_EVENT_ATTR(lp-xact-credit, 0x27),
196 	IMX8_DDR_PMU_EVENT_ATTR(wr-xact-credit, 0x29),
197 	IMX8_DDR_PMU_EVENT_ATTR(read-cycles, 0x2a),
198 	IMX8_DDR_PMU_EVENT_ATTR(write-cycles, 0x2b),
199 	IMX8_DDR_PMU_EVENT_ATTR(read-write-transition, 0x30),
200 	IMX8_DDR_PMU_EVENT_ATTR(precharge, 0x31),
201 	IMX8_DDR_PMU_EVENT_ATTR(activate, 0x32),
202 	IMX8_DDR_PMU_EVENT_ATTR(load-mode, 0x33),
203 	IMX8_DDR_PMU_EVENT_ATTR(perf-mwr, 0x34),
204 	IMX8_DDR_PMU_EVENT_ATTR(read, 0x35),
205 	IMX8_DDR_PMU_EVENT_ATTR(read-activate, 0x36),
206 	IMX8_DDR_PMU_EVENT_ATTR(refresh, 0x37),
207 	IMX8_DDR_PMU_EVENT_ATTR(write, 0x38),
208 	IMX8_DDR_PMU_EVENT_ATTR(raw-hazard, 0x39),
209 	IMX8_DDR_PMU_EVENT_ATTR(axid-read, 0x41),
210 	IMX8_DDR_PMU_EVENT_ATTR(axid-write, 0x42),
211 	NULL,
212 };
213 
214 static struct attribute_group ddr_perf_events_attr_group = {
215 	.name = "events",
216 	.attrs = ddr_perf_events_attrs,
217 };
218 
219 PMU_FORMAT_ATTR(event, "config:0-7");
220 PMU_FORMAT_ATTR(axi_id, "config1:0-15");
221 PMU_FORMAT_ATTR(axi_mask, "config1:16-31");
222 
223 static struct attribute *ddr_perf_format_attrs[] = {
224 	&format_attr_event.attr,
225 	&format_attr_axi_id.attr,
226 	&format_attr_axi_mask.attr,
227 	NULL,
228 };
229 
230 static struct attribute_group ddr_perf_format_attr_group = {
231 	.name = "format",
232 	.attrs = ddr_perf_format_attrs,
233 };
234 
235 static const struct attribute_group *attr_groups[] = {
236 	&ddr_perf_events_attr_group,
237 	&ddr_perf_format_attr_group,
238 	&ddr_perf_cpumask_attr_group,
239 	&ddr_perf_filter_cap_attr_group,
240 	NULL,
241 };
242 
243 static bool ddr_perf_is_filtered(struct perf_event *event)
244 {
245 	return event->attr.config == 0x41 || event->attr.config == 0x42;
246 }
247 
248 static u32 ddr_perf_filter_val(struct perf_event *event)
249 {
250 	return event->attr.config1;
251 }
252 
253 static bool ddr_perf_filters_compatible(struct perf_event *a,
254 					struct perf_event *b)
255 {
256 	if (!ddr_perf_is_filtered(a))
257 		return true;
258 	if (!ddr_perf_is_filtered(b))
259 		return true;
260 	return ddr_perf_filter_val(a) == ddr_perf_filter_val(b);
261 }
262 
263 static bool ddr_perf_is_enhanced_filtered(struct perf_event *event)
264 {
265 	unsigned int filt;
266 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
267 
268 	filt = pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER_ENHANCED;
269 	return (filt == DDR_CAP_AXI_ID_FILTER_ENHANCED) &&
270 		ddr_perf_is_filtered(event);
271 }
272 
273 static u32 ddr_perf_alloc_counter(struct ddr_pmu *pmu, int event)
274 {
275 	int i;
276 
277 	/*
278 	 * Always map cycle event to counter 0
279 	 * Cycles counter is dedicated for cycle event
280 	 * can't used for the other events
281 	 */
282 	if (event == EVENT_CYCLES_ID) {
283 		if (pmu->events[EVENT_CYCLES_COUNTER] == NULL)
284 			return EVENT_CYCLES_COUNTER;
285 		else
286 			return -ENOENT;
287 	}
288 
289 	for (i = 1; i < NUM_COUNTERS; i++) {
290 		if (pmu->events[i] == NULL)
291 			return i;
292 	}
293 
294 	return -ENOENT;
295 }
296 
297 static void ddr_perf_free_counter(struct ddr_pmu *pmu, int counter)
298 {
299 	pmu->events[counter] = NULL;
300 }
301 
302 static u32 ddr_perf_read_counter(struct ddr_pmu *pmu, int counter)
303 {
304 	struct perf_event *event = pmu->events[counter];
305 	void __iomem *base = pmu->base;
306 
307 	/*
308 	 * return bytes instead of bursts from ddr transaction for
309 	 * axid-read and axid-write event if PMU core supports enhanced
310 	 * filter.
311 	 */
312 	base += ddr_perf_is_enhanced_filtered(event) ? COUNTER_DPCR1 :
313 						       COUNTER_READ;
314 	return readl_relaxed(base + counter * 4);
315 }
316 
317 static int ddr_perf_event_init(struct perf_event *event)
318 {
319 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
320 	struct hw_perf_event *hwc = &event->hw;
321 	struct perf_event *sibling;
322 
323 	if (event->attr.type != event->pmu->type)
324 		return -ENOENT;
325 
326 	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
327 		return -EOPNOTSUPP;
328 
329 	if (event->cpu < 0) {
330 		dev_warn(pmu->dev, "Can't provide per-task data!\n");
331 		return -EOPNOTSUPP;
332 	}
333 
334 	/*
335 	 * We must NOT create groups containing mixed PMUs, although software
336 	 * events are acceptable (for example to create a CCN group
337 	 * periodically read when a hrtimer aka cpu-clock leader triggers).
338 	 */
339 	if (event->group_leader->pmu != event->pmu &&
340 			!is_software_event(event->group_leader))
341 		return -EINVAL;
342 
343 	if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER) {
344 		if (!ddr_perf_filters_compatible(event, event->group_leader))
345 			return -EINVAL;
346 		for_each_sibling_event(sibling, event->group_leader) {
347 			if (!ddr_perf_filters_compatible(event, sibling))
348 				return -EINVAL;
349 		}
350 	}
351 
352 	for_each_sibling_event(sibling, event->group_leader) {
353 		if (sibling->pmu != event->pmu &&
354 				!is_software_event(sibling))
355 			return -EINVAL;
356 	}
357 
358 	event->cpu = pmu->cpu;
359 	hwc->idx = -1;
360 
361 	return 0;
362 }
363 
364 
365 static void ddr_perf_event_update(struct perf_event *event)
366 {
367 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
368 	struct hw_perf_event *hwc = &event->hw;
369 	u64 delta, prev_raw_count, new_raw_count;
370 	int counter = hwc->idx;
371 
372 	do {
373 		prev_raw_count = local64_read(&hwc->prev_count);
374 		new_raw_count = ddr_perf_read_counter(pmu, counter);
375 	} while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
376 			new_raw_count) != prev_raw_count);
377 
378 	delta = (new_raw_count - prev_raw_count) & 0xFFFFFFFF;
379 
380 	local64_add(delta, &event->count);
381 }
382 
383 static void ddr_perf_counter_enable(struct ddr_pmu *pmu, int config,
384 				  int counter, bool enable)
385 {
386 	u8 reg = counter * 4 + COUNTER_CNTL;
387 	int val;
388 
389 	if (enable) {
390 		/*
391 		 * must disable first, then enable again
392 		 * otherwise, cycle counter will not work
393 		 * if previous state is enabled.
394 		 */
395 		writel(0, pmu->base + reg);
396 		val = CNTL_EN | CNTL_CLEAR;
397 		val |= FIELD_PREP(CNTL_CSV_MASK, config);
398 		writel(val, pmu->base + reg);
399 	} else {
400 		/* Disable counter */
401 		writel(0, pmu->base + reg);
402 	}
403 }
404 
405 static void ddr_perf_event_start(struct perf_event *event, int flags)
406 {
407 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
408 	struct hw_perf_event *hwc = &event->hw;
409 	int counter = hwc->idx;
410 
411 	local64_set(&hwc->prev_count, 0);
412 
413 	ddr_perf_counter_enable(pmu, event->attr.config, counter, true);
414 
415 	hwc->state = 0;
416 }
417 
418 static int ddr_perf_event_add(struct perf_event *event, int flags)
419 {
420 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
421 	struct hw_perf_event *hwc = &event->hw;
422 	int counter;
423 	int cfg = event->attr.config;
424 	int cfg1 = event->attr.config1;
425 
426 	if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER) {
427 		int i;
428 
429 		for (i = 1; i < NUM_COUNTERS; i++) {
430 			if (pmu->events[i] &&
431 			    !ddr_perf_filters_compatible(event, pmu->events[i]))
432 				return -EINVAL;
433 		}
434 
435 		if (ddr_perf_is_filtered(event)) {
436 			/* revert axi id masking(axi_mask) value */
437 			cfg1 ^= AXI_MASKING_REVERT;
438 			writel(cfg1, pmu->base + COUNTER_DPCR1);
439 		}
440 	}
441 
442 	counter = ddr_perf_alloc_counter(pmu, cfg);
443 	if (counter < 0) {
444 		dev_dbg(pmu->dev, "There are not enough counters\n");
445 		return -EOPNOTSUPP;
446 	}
447 
448 	pmu->events[counter] = event;
449 	pmu->active_events++;
450 	hwc->idx = counter;
451 
452 	hwc->state |= PERF_HES_STOPPED;
453 
454 	if (flags & PERF_EF_START)
455 		ddr_perf_event_start(event, flags);
456 
457 	return 0;
458 }
459 
460 static void ddr_perf_event_stop(struct perf_event *event, int flags)
461 {
462 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
463 	struct hw_perf_event *hwc = &event->hw;
464 	int counter = hwc->idx;
465 
466 	ddr_perf_counter_enable(pmu, event->attr.config, counter, false);
467 	ddr_perf_event_update(event);
468 
469 	hwc->state |= PERF_HES_STOPPED;
470 }
471 
472 static void ddr_perf_event_del(struct perf_event *event, int flags)
473 {
474 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
475 	struct hw_perf_event *hwc = &event->hw;
476 	int counter = hwc->idx;
477 
478 	ddr_perf_event_stop(event, PERF_EF_UPDATE);
479 
480 	ddr_perf_free_counter(pmu, counter);
481 	pmu->active_events--;
482 	hwc->idx = -1;
483 }
484 
485 static void ddr_perf_pmu_enable(struct pmu *pmu)
486 {
487 	struct ddr_pmu *ddr_pmu = to_ddr_pmu(pmu);
488 
489 	/* enable cycle counter if cycle is not active event list */
490 	if (ddr_pmu->events[EVENT_CYCLES_COUNTER] == NULL)
491 		ddr_perf_counter_enable(ddr_pmu,
492 				      EVENT_CYCLES_ID,
493 				      EVENT_CYCLES_COUNTER,
494 				      true);
495 }
496 
497 static void ddr_perf_pmu_disable(struct pmu *pmu)
498 {
499 	struct ddr_pmu *ddr_pmu = to_ddr_pmu(pmu);
500 
501 	if (ddr_pmu->events[EVENT_CYCLES_COUNTER] == NULL)
502 		ddr_perf_counter_enable(ddr_pmu,
503 				      EVENT_CYCLES_ID,
504 				      EVENT_CYCLES_COUNTER,
505 				      false);
506 }
507 
508 static int ddr_perf_init(struct ddr_pmu *pmu, void __iomem *base,
509 			 struct device *dev)
510 {
511 	*pmu = (struct ddr_pmu) {
512 		.pmu = (struct pmu) {
513 			.capabilities = PERF_PMU_CAP_NO_EXCLUDE,
514 			.task_ctx_nr = perf_invalid_context,
515 			.attr_groups = attr_groups,
516 			.event_init  = ddr_perf_event_init,
517 			.add	     = ddr_perf_event_add,
518 			.del	     = ddr_perf_event_del,
519 			.start	     = ddr_perf_event_start,
520 			.stop	     = ddr_perf_event_stop,
521 			.read	     = ddr_perf_event_update,
522 			.pmu_enable  = ddr_perf_pmu_enable,
523 			.pmu_disable = ddr_perf_pmu_disable,
524 		},
525 		.base = base,
526 		.dev = dev,
527 	};
528 
529 	pmu->id = ida_simple_get(&ddr_ida, 0, 0, GFP_KERNEL);
530 	return pmu->id;
531 }
532 
533 static irqreturn_t ddr_perf_irq_handler(int irq, void *p)
534 {
535 	int i;
536 	struct ddr_pmu *pmu = (struct ddr_pmu *) p;
537 	struct perf_event *event, *cycle_event = NULL;
538 
539 	/* all counter will stop if cycle counter disabled */
540 	ddr_perf_counter_enable(pmu,
541 			      EVENT_CYCLES_ID,
542 			      EVENT_CYCLES_COUNTER,
543 			      false);
544 	/*
545 	 * When the cycle counter overflows, all counters are stopped,
546 	 * and an IRQ is raised. If any other counter overflows, it
547 	 * continues counting, and no IRQ is raised.
548 	 *
549 	 * Cycles occur at least 4 times as often as other events, so we
550 	 * can update all events on a cycle counter overflow and not
551 	 * lose events.
552 	 *
553 	 */
554 	for (i = 0; i < NUM_COUNTERS; i++) {
555 
556 		if (!pmu->events[i])
557 			continue;
558 
559 		event = pmu->events[i];
560 
561 		ddr_perf_event_update(event);
562 
563 		if (event->hw.idx == EVENT_CYCLES_COUNTER)
564 			cycle_event = event;
565 	}
566 
567 	ddr_perf_counter_enable(pmu,
568 			      EVENT_CYCLES_ID,
569 			      EVENT_CYCLES_COUNTER,
570 			      true);
571 	if (cycle_event)
572 		ddr_perf_event_update(cycle_event);
573 
574 	return IRQ_HANDLED;
575 }
576 
577 static int ddr_perf_offline_cpu(unsigned int cpu, struct hlist_node *node)
578 {
579 	struct ddr_pmu *pmu = hlist_entry_safe(node, struct ddr_pmu, node);
580 	int target;
581 
582 	if (cpu != pmu->cpu)
583 		return 0;
584 
585 	target = cpumask_any_but(cpu_online_mask, cpu);
586 	if (target >= nr_cpu_ids)
587 		return 0;
588 
589 	perf_pmu_migrate_context(&pmu->pmu, cpu, target);
590 	pmu->cpu = target;
591 
592 	WARN_ON(irq_set_affinity_hint(pmu->irq, cpumask_of(pmu->cpu)));
593 
594 	return 0;
595 }
596 
597 static int ddr_perf_probe(struct platform_device *pdev)
598 {
599 	struct ddr_pmu *pmu;
600 	struct device_node *np;
601 	void __iomem *base;
602 	char *name;
603 	int num;
604 	int ret;
605 	int irq;
606 
607 	base = devm_platform_ioremap_resource(pdev, 0);
608 	if (IS_ERR(base))
609 		return PTR_ERR(base);
610 
611 	np = pdev->dev.of_node;
612 
613 	pmu = devm_kzalloc(&pdev->dev, sizeof(*pmu), GFP_KERNEL);
614 	if (!pmu)
615 		return -ENOMEM;
616 
617 	num = ddr_perf_init(pmu, base, &pdev->dev);
618 
619 	platform_set_drvdata(pdev, pmu);
620 
621 	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, DDR_PERF_DEV_NAME "%d",
622 			      num);
623 	if (!name)
624 		return -ENOMEM;
625 
626 	pmu->devtype_data = of_device_get_match_data(&pdev->dev);
627 
628 	pmu->cpu = raw_smp_processor_id();
629 	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
630 				      DDR_CPUHP_CB_NAME,
631 				      NULL,
632 				      ddr_perf_offline_cpu);
633 
634 	if (ret < 0) {
635 		dev_err(&pdev->dev, "cpuhp_setup_state_multi failed\n");
636 		goto ddr_perf_err;
637 	}
638 
639 	pmu->cpuhp_state = ret;
640 
641 	/* Register the pmu instance for cpu hotplug */
642 	cpuhp_state_add_instance_nocalls(pmu->cpuhp_state, &pmu->node);
643 
644 	/* Request irq */
645 	irq = of_irq_get(np, 0);
646 	if (irq < 0) {
647 		dev_err(&pdev->dev, "Failed to get irq: %d", irq);
648 		ret = irq;
649 		goto ddr_perf_err;
650 	}
651 
652 	ret = devm_request_irq(&pdev->dev, irq,
653 					ddr_perf_irq_handler,
654 					IRQF_NOBALANCING | IRQF_NO_THREAD,
655 					DDR_CPUHP_CB_NAME,
656 					pmu);
657 	if (ret < 0) {
658 		dev_err(&pdev->dev, "Request irq failed: %d", ret);
659 		goto ddr_perf_err;
660 	}
661 
662 	pmu->irq = irq;
663 	ret = irq_set_affinity_hint(pmu->irq, cpumask_of(pmu->cpu));
664 	if (ret) {
665 		dev_err(pmu->dev, "Failed to set interrupt affinity!\n");
666 		goto ddr_perf_err;
667 	}
668 
669 	ret = perf_pmu_register(&pmu->pmu, name, -1);
670 	if (ret)
671 		goto ddr_perf_err;
672 
673 	return 0;
674 
675 ddr_perf_err:
676 	if (pmu->cpuhp_state)
677 		cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
678 
679 	ida_simple_remove(&ddr_ida, pmu->id);
680 	dev_warn(&pdev->dev, "i.MX8 DDR Perf PMU failed (%d), disabled\n", ret);
681 	return ret;
682 }
683 
684 static int ddr_perf_remove(struct platform_device *pdev)
685 {
686 	struct ddr_pmu *pmu = platform_get_drvdata(pdev);
687 
688 	cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
689 	irq_set_affinity_hint(pmu->irq, NULL);
690 
691 	perf_pmu_unregister(&pmu->pmu);
692 
693 	ida_simple_remove(&ddr_ida, pmu->id);
694 	return 0;
695 }
696 
697 static struct platform_driver imx_ddr_pmu_driver = {
698 	.driver         = {
699 		.name   = "imx-ddr-pmu",
700 		.of_match_table = imx_ddr_pmu_dt_ids,
701 	},
702 	.probe          = ddr_perf_probe,
703 	.remove         = ddr_perf_remove,
704 };
705 
706 module_platform_driver(imx_ddr_pmu_driver);
707 MODULE_LICENSE("GPL v2");
708