xref: /linux/drivers/perf/fsl_imx8_ddr_perf.c (revision 7255fcc80d4b525cc10cfaaf7f485830d4ed2000)
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_irq.h>
14 #include <linux/perf_event.h>
15 #include <linux/platform_device.h>
16 #include <linux/slab.h>
17 
18 #define COUNTER_CNTL		0x0
19 #define COUNTER_READ		0x20
20 
21 #define COUNTER_DPCR1		0x30
22 #define COUNTER_MUX_CNTL	0x50
23 #define COUNTER_MASK_COMP	0x54
24 
25 #define CNTL_OVER		0x1
26 #define CNTL_CLEAR		0x2
27 #define CNTL_EN			0x4
28 #define CNTL_EN_MASK		0xFFFFFFFB
29 #define CNTL_CLEAR_MASK		0xFFFFFFFD
30 #define CNTL_OVER_MASK		0xFFFFFFFE
31 
32 #define CNTL_CP_SHIFT		16
33 #define CNTL_CP_MASK		(0xFF << CNTL_CP_SHIFT)
34 #define CNTL_CSV_SHIFT		24
35 #define CNTL_CSV_MASK		(0xFFU << CNTL_CSV_SHIFT)
36 
37 #define READ_PORT_SHIFT		0
38 #define READ_PORT_MASK		(0x7 << READ_PORT_SHIFT)
39 #define READ_CHANNEL_REVERT	0x00000008	/* bit 3 for read channel select */
40 #define WRITE_PORT_SHIFT	8
41 #define WRITE_PORT_MASK		(0x7 << WRITE_PORT_SHIFT)
42 #define WRITE_CHANNEL_REVERT	0x00000800	/* bit 11 for write channel select */
43 
44 #define EVENT_CYCLES_ID		0
45 #define EVENT_CYCLES_COUNTER	0
46 #define NUM_COUNTERS		4
47 
48 /* For removing bias if cycle counter CNTL.CP is set to 0xf0 */
49 #define CYCLES_COUNTER_MASK	0x0FFFFFFF
50 #define AXI_MASKING_REVERT	0xffff0000	/* AXI_MASKING(MSB 16bits) + AXI_ID(LSB 16bits) */
51 
52 #define to_ddr_pmu(p)		container_of(p, struct ddr_pmu, pmu)
53 
54 #define DDR_PERF_DEV_NAME	"imx8_ddr"
55 #define DDR_CPUHP_CB_NAME	DDR_PERF_DEV_NAME "_perf_pmu"
56 
57 static DEFINE_IDA(ddr_ida);
58 
59 /* DDR Perf hardware feature */
60 #define DDR_CAP_AXI_ID_FILTER			0x1     /* support AXI ID filter */
61 #define DDR_CAP_AXI_ID_FILTER_ENHANCED		0x3     /* support enhanced AXI ID filter */
62 #define DDR_CAP_AXI_ID_PORT_CHANNEL_FILTER	0x4	/* support AXI ID PORT CHANNEL filter */
63 
64 struct fsl_ddr_devtype_data {
65 	unsigned int quirks;    /* quirks needed for different DDR Perf core */
66 	const char *identifier;	/* system PMU identifier for userspace */
67 };
68 
69 static const struct fsl_ddr_devtype_data imx8_devtype_data;
70 
71 static const struct fsl_ddr_devtype_data imx8m_devtype_data = {
72 	.quirks = DDR_CAP_AXI_ID_FILTER,
73 };
74 
75 static const struct fsl_ddr_devtype_data imx8mq_devtype_data = {
76 	.quirks = DDR_CAP_AXI_ID_FILTER,
77 	.identifier = "i.MX8MQ",
78 };
79 
80 static const struct fsl_ddr_devtype_data imx8mm_devtype_data = {
81 	.quirks = DDR_CAP_AXI_ID_FILTER,
82 	.identifier = "i.MX8MM",
83 };
84 
85 static const struct fsl_ddr_devtype_data imx8mn_devtype_data = {
86 	.quirks = DDR_CAP_AXI_ID_FILTER,
87 	.identifier = "i.MX8MN",
88 };
89 
90 static const struct fsl_ddr_devtype_data imx8mp_devtype_data = {
91 	.quirks = DDR_CAP_AXI_ID_FILTER_ENHANCED,
92 	.identifier = "i.MX8MP",
93 };
94 
95 static const struct fsl_ddr_devtype_data imx8dxl_devtype_data = {
96 	.quirks = DDR_CAP_AXI_ID_PORT_CHANNEL_FILTER,
97 	.identifier = "i.MX8DXL",
98 };
99 
100 static const struct of_device_id imx_ddr_pmu_dt_ids[] = {
101 	{ .compatible = "fsl,imx8-ddr-pmu", .data = &imx8_devtype_data},
102 	{ .compatible = "fsl,imx8m-ddr-pmu", .data = &imx8m_devtype_data},
103 	{ .compatible = "fsl,imx8mq-ddr-pmu", .data = &imx8mq_devtype_data},
104 	{ .compatible = "fsl,imx8mm-ddr-pmu", .data = &imx8mm_devtype_data},
105 	{ .compatible = "fsl,imx8mn-ddr-pmu", .data = &imx8mn_devtype_data},
106 	{ .compatible = "fsl,imx8mp-ddr-pmu", .data = &imx8mp_devtype_data},
107 	{ .compatible = "fsl,imx8dxl-ddr-pmu", .data = &imx8dxl_devtype_data},
108 	{ /* sentinel */ }
109 };
110 MODULE_DEVICE_TABLE(of, imx_ddr_pmu_dt_ids);
111 
112 struct ddr_pmu {
113 	struct pmu pmu;
114 	void __iomem *base;
115 	unsigned int cpu;
116 	struct	hlist_node node;
117 	struct	device *dev;
118 	struct perf_event *events[NUM_COUNTERS];
119 	enum cpuhp_state cpuhp_state;
120 	const struct fsl_ddr_devtype_data *devtype_data;
121 	int irq;
122 	int id;
123 	int active_counter;
124 };
125 
126 static ssize_t ddr_perf_identifier_show(struct device *dev,
127 					struct device_attribute *attr,
128 					char *page)
129 {
130 	struct ddr_pmu *pmu = dev_get_drvdata(dev);
131 
132 	return sysfs_emit(page, "%s\n", pmu->devtype_data->identifier);
133 }
134 
135 static umode_t ddr_perf_identifier_attr_visible(struct kobject *kobj,
136 						struct attribute *attr,
137 						int n)
138 {
139 	struct device *dev = kobj_to_dev(kobj);
140 	struct ddr_pmu *pmu = dev_get_drvdata(dev);
141 
142 	if (!pmu->devtype_data->identifier)
143 		return 0;
144 	return attr->mode;
145 };
146 
147 static struct device_attribute ddr_perf_identifier_attr =
148 	__ATTR(identifier, 0444, ddr_perf_identifier_show, NULL);
149 
150 static struct attribute *ddr_perf_identifier_attrs[] = {
151 	&ddr_perf_identifier_attr.attr,
152 	NULL,
153 };
154 
155 static const struct attribute_group ddr_perf_identifier_attr_group = {
156 	.attrs = ddr_perf_identifier_attrs,
157 	.is_visible = ddr_perf_identifier_attr_visible,
158 };
159 
160 enum ddr_perf_filter_capabilities {
161 	PERF_CAP_AXI_ID_FILTER = 0,
162 	PERF_CAP_AXI_ID_FILTER_ENHANCED,
163 	PERF_CAP_AXI_ID_PORT_CHANNEL_FILTER,
164 	PERF_CAP_AXI_ID_FEAT_MAX,
165 };
166 
167 static u32 ddr_perf_filter_cap_get(struct ddr_pmu *pmu, int cap)
168 {
169 	u32 quirks = pmu->devtype_data->quirks;
170 
171 	switch (cap) {
172 	case PERF_CAP_AXI_ID_FILTER:
173 		return !!(quirks & DDR_CAP_AXI_ID_FILTER);
174 	case PERF_CAP_AXI_ID_FILTER_ENHANCED:
175 		quirks &= DDR_CAP_AXI_ID_FILTER_ENHANCED;
176 		return quirks == DDR_CAP_AXI_ID_FILTER_ENHANCED;
177 	case PERF_CAP_AXI_ID_PORT_CHANNEL_FILTER:
178 		return !!(quirks & DDR_CAP_AXI_ID_PORT_CHANNEL_FILTER);
179 	default:
180 		WARN(1, "unknown filter cap %d\n", cap);
181 	}
182 
183 	return 0;
184 }
185 
186 static ssize_t ddr_perf_filter_cap_show(struct device *dev,
187 					struct device_attribute *attr,
188 					char *buf)
189 {
190 	struct ddr_pmu *pmu = dev_get_drvdata(dev);
191 	struct dev_ext_attribute *ea =
192 		container_of(attr, struct dev_ext_attribute, attr);
193 	int cap = (long)ea->var;
194 
195 	return sysfs_emit(buf, "%u\n", ddr_perf_filter_cap_get(pmu, cap));
196 }
197 
198 #define PERF_EXT_ATTR_ENTRY(_name, _func, _var)				\
199 	(&((struct dev_ext_attribute) {					\
200 		__ATTR(_name, 0444, _func, NULL), (void *)_var		\
201 	}).attr.attr)
202 
203 #define PERF_FILTER_EXT_ATTR_ENTRY(_name, _var)				\
204 	PERF_EXT_ATTR_ENTRY(_name, ddr_perf_filter_cap_show, _var)
205 
206 static struct attribute *ddr_perf_filter_cap_attr[] = {
207 	PERF_FILTER_EXT_ATTR_ENTRY(filter, PERF_CAP_AXI_ID_FILTER),
208 	PERF_FILTER_EXT_ATTR_ENTRY(enhanced_filter, PERF_CAP_AXI_ID_FILTER_ENHANCED),
209 	PERF_FILTER_EXT_ATTR_ENTRY(super_filter, PERF_CAP_AXI_ID_PORT_CHANNEL_FILTER),
210 	NULL,
211 };
212 
213 static const struct attribute_group ddr_perf_filter_cap_attr_group = {
214 	.name = "caps",
215 	.attrs = ddr_perf_filter_cap_attr,
216 };
217 
218 static ssize_t ddr_perf_cpumask_show(struct device *dev,
219 				struct device_attribute *attr, char *buf)
220 {
221 	struct ddr_pmu *pmu = dev_get_drvdata(dev);
222 
223 	return cpumap_print_to_pagebuf(true, buf, cpumask_of(pmu->cpu));
224 }
225 
226 static struct device_attribute ddr_perf_cpumask_attr =
227 	__ATTR(cpumask, 0444, ddr_perf_cpumask_show, NULL);
228 
229 static struct attribute *ddr_perf_cpumask_attrs[] = {
230 	&ddr_perf_cpumask_attr.attr,
231 	NULL,
232 };
233 
234 static const struct attribute_group ddr_perf_cpumask_attr_group = {
235 	.attrs = ddr_perf_cpumask_attrs,
236 };
237 
238 static ssize_t
239 ddr_pmu_event_show(struct device *dev, struct device_attribute *attr,
240 		   char *page)
241 {
242 	struct perf_pmu_events_attr *pmu_attr;
243 
244 	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
245 	return sysfs_emit(page, "event=0x%02llx\n", pmu_attr->id);
246 }
247 
248 #define IMX8_DDR_PMU_EVENT_ATTR(_name, _id)		\
249 	PMU_EVENT_ATTR_ID(_name, ddr_pmu_event_show, _id)
250 
251 static struct attribute *ddr_perf_events_attrs[] = {
252 	IMX8_DDR_PMU_EVENT_ATTR(cycles, EVENT_CYCLES_ID),
253 	IMX8_DDR_PMU_EVENT_ATTR(selfresh, 0x01),
254 	IMX8_DDR_PMU_EVENT_ATTR(read-accesses, 0x04),
255 	IMX8_DDR_PMU_EVENT_ATTR(write-accesses, 0x05),
256 	IMX8_DDR_PMU_EVENT_ATTR(read-queue-depth, 0x08),
257 	IMX8_DDR_PMU_EVENT_ATTR(write-queue-depth, 0x09),
258 	IMX8_DDR_PMU_EVENT_ATTR(lp-read-credit-cnt, 0x10),
259 	IMX8_DDR_PMU_EVENT_ATTR(hp-read-credit-cnt, 0x11),
260 	IMX8_DDR_PMU_EVENT_ATTR(write-credit-cnt, 0x12),
261 	IMX8_DDR_PMU_EVENT_ATTR(read-command, 0x20),
262 	IMX8_DDR_PMU_EVENT_ATTR(write-command, 0x21),
263 	IMX8_DDR_PMU_EVENT_ATTR(read-modify-write-command, 0x22),
264 	IMX8_DDR_PMU_EVENT_ATTR(hp-read, 0x23),
265 	IMX8_DDR_PMU_EVENT_ATTR(hp-req-nocredit, 0x24),
266 	IMX8_DDR_PMU_EVENT_ATTR(hp-xact-credit, 0x25),
267 	IMX8_DDR_PMU_EVENT_ATTR(lp-req-nocredit, 0x26),
268 	IMX8_DDR_PMU_EVENT_ATTR(lp-xact-credit, 0x27),
269 	IMX8_DDR_PMU_EVENT_ATTR(wr-xact-credit, 0x29),
270 	IMX8_DDR_PMU_EVENT_ATTR(read-cycles, 0x2a),
271 	IMX8_DDR_PMU_EVENT_ATTR(write-cycles, 0x2b),
272 	IMX8_DDR_PMU_EVENT_ATTR(read-write-transition, 0x30),
273 	IMX8_DDR_PMU_EVENT_ATTR(precharge, 0x31),
274 	IMX8_DDR_PMU_EVENT_ATTR(activate, 0x32),
275 	IMX8_DDR_PMU_EVENT_ATTR(load-mode, 0x33),
276 	IMX8_DDR_PMU_EVENT_ATTR(perf-mwr, 0x34),
277 	IMX8_DDR_PMU_EVENT_ATTR(read, 0x35),
278 	IMX8_DDR_PMU_EVENT_ATTR(read-activate, 0x36),
279 	IMX8_DDR_PMU_EVENT_ATTR(refresh, 0x37),
280 	IMX8_DDR_PMU_EVENT_ATTR(write, 0x38),
281 	IMX8_DDR_PMU_EVENT_ATTR(raw-hazard, 0x39),
282 	IMX8_DDR_PMU_EVENT_ATTR(axid-read, 0x41),
283 	IMX8_DDR_PMU_EVENT_ATTR(axid-write, 0x42),
284 	NULL,
285 };
286 
287 static const struct attribute_group ddr_perf_events_attr_group = {
288 	.name = "events",
289 	.attrs = ddr_perf_events_attrs,
290 };
291 
292 PMU_FORMAT_ATTR(event, "config:0-7");
293 PMU_FORMAT_ATTR(axi_id, "config1:0-15");
294 PMU_FORMAT_ATTR(axi_mask, "config1:16-31");
295 PMU_FORMAT_ATTR(axi_port, "config2:0-2");
296 PMU_FORMAT_ATTR(axi_channel, "config2:3-3");
297 
298 static struct attribute *ddr_perf_format_attrs[] = {
299 	&format_attr_event.attr,
300 	&format_attr_axi_id.attr,
301 	&format_attr_axi_mask.attr,
302 	&format_attr_axi_port.attr,
303 	&format_attr_axi_channel.attr,
304 	NULL,
305 };
306 
307 static const struct attribute_group ddr_perf_format_attr_group = {
308 	.name = "format",
309 	.attrs = ddr_perf_format_attrs,
310 };
311 
312 static const struct attribute_group *attr_groups[] = {
313 	&ddr_perf_events_attr_group,
314 	&ddr_perf_format_attr_group,
315 	&ddr_perf_cpumask_attr_group,
316 	&ddr_perf_filter_cap_attr_group,
317 	&ddr_perf_identifier_attr_group,
318 	NULL,
319 };
320 
321 static bool ddr_perf_is_filtered(struct perf_event *event)
322 {
323 	return event->attr.config == 0x41 || event->attr.config == 0x42;
324 }
325 
326 static u32 ddr_perf_filter_val(struct perf_event *event)
327 {
328 	return event->attr.config1;
329 }
330 
331 static bool ddr_perf_filters_compatible(struct perf_event *a,
332 					struct perf_event *b)
333 {
334 	if (!ddr_perf_is_filtered(a))
335 		return true;
336 	if (!ddr_perf_is_filtered(b))
337 		return true;
338 	return ddr_perf_filter_val(a) == ddr_perf_filter_val(b);
339 }
340 
341 static bool ddr_perf_is_enhanced_filtered(struct perf_event *event)
342 {
343 	unsigned int filt;
344 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
345 
346 	filt = pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER_ENHANCED;
347 	return (filt == DDR_CAP_AXI_ID_FILTER_ENHANCED) &&
348 		ddr_perf_is_filtered(event);
349 }
350 
351 static u32 ddr_perf_alloc_counter(struct ddr_pmu *pmu, int event)
352 {
353 	int i;
354 
355 	/*
356 	 * Always map cycle event to counter 0
357 	 * Cycles counter is dedicated for cycle event
358 	 * can't used for the other events
359 	 */
360 	if (event == EVENT_CYCLES_ID) {
361 		if (pmu->events[EVENT_CYCLES_COUNTER] == NULL)
362 			return EVENT_CYCLES_COUNTER;
363 		else
364 			return -ENOENT;
365 	}
366 
367 	for (i = 1; i < NUM_COUNTERS; i++) {
368 		if (pmu->events[i] == NULL)
369 			return i;
370 	}
371 
372 	return -ENOENT;
373 }
374 
375 static void ddr_perf_free_counter(struct ddr_pmu *pmu, int counter)
376 {
377 	pmu->events[counter] = NULL;
378 }
379 
380 static u32 ddr_perf_read_counter(struct ddr_pmu *pmu, int counter)
381 {
382 	struct perf_event *event = pmu->events[counter];
383 	void __iomem *base = pmu->base;
384 
385 	/*
386 	 * return bytes instead of bursts from ddr transaction for
387 	 * axid-read and axid-write event if PMU core supports enhanced
388 	 * filter.
389 	 */
390 	base += ddr_perf_is_enhanced_filtered(event) ? COUNTER_DPCR1 :
391 						       COUNTER_READ;
392 	return readl_relaxed(base + counter * 4);
393 }
394 
395 static int ddr_perf_event_init(struct perf_event *event)
396 {
397 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
398 	struct hw_perf_event *hwc = &event->hw;
399 	struct perf_event *sibling;
400 
401 	if (event->attr.type != event->pmu->type)
402 		return -ENOENT;
403 
404 	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
405 		return -EOPNOTSUPP;
406 
407 	if (event->cpu < 0) {
408 		dev_warn(pmu->dev, "Can't provide per-task data!\n");
409 		return -EOPNOTSUPP;
410 	}
411 
412 	/*
413 	 * We must NOT create groups containing mixed PMUs, although software
414 	 * events are acceptable (for example to create a CCN group
415 	 * periodically read when a hrtimer aka cpu-clock leader triggers).
416 	 */
417 	if (event->group_leader->pmu != event->pmu &&
418 			!is_software_event(event->group_leader))
419 		return -EINVAL;
420 
421 	if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER) {
422 		if (!ddr_perf_filters_compatible(event, event->group_leader))
423 			return -EINVAL;
424 		for_each_sibling_event(sibling, event->group_leader) {
425 			if (!ddr_perf_filters_compatible(event, sibling))
426 				return -EINVAL;
427 		}
428 	}
429 
430 	for_each_sibling_event(sibling, event->group_leader) {
431 		if (sibling->pmu != event->pmu &&
432 				!is_software_event(sibling))
433 			return -EINVAL;
434 	}
435 
436 	event->cpu = pmu->cpu;
437 	hwc->idx = -1;
438 
439 	return 0;
440 }
441 
442 static void ddr_perf_counter_enable(struct ddr_pmu *pmu, int config,
443 				  int counter, bool enable)
444 {
445 	u8 reg = counter * 4 + COUNTER_CNTL;
446 	int val;
447 
448 	if (enable) {
449 		/*
450 		 * cycle counter is special which should firstly write 0 then
451 		 * write 1 into CLEAR bit to clear it. Other counters only
452 		 * need write 0 into CLEAR bit and it turns out to be 1 by
453 		 * hardware. Below enable flow is harmless for all counters.
454 		 */
455 		writel(0, pmu->base + reg);
456 		val = CNTL_EN | CNTL_CLEAR;
457 		val |= FIELD_PREP(CNTL_CSV_MASK, config);
458 
459 		/*
460 		 * On i.MX8MP we need to bias the cycle counter to overflow more often.
461 		 * We do this by initializing bits [23:16] of the counter value via the
462 		 * COUNTER_CTRL Counter Parameter (CP) field.
463 		 */
464 		if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER_ENHANCED) {
465 			if (counter == EVENT_CYCLES_COUNTER)
466 				val |= FIELD_PREP(CNTL_CP_MASK, 0xf0);
467 		}
468 
469 		writel(val, pmu->base + reg);
470 	} else {
471 		/* Disable counter */
472 		val = readl_relaxed(pmu->base + reg) & CNTL_EN_MASK;
473 		writel(val, pmu->base + reg);
474 	}
475 }
476 
477 static bool ddr_perf_counter_overflow(struct ddr_pmu *pmu, int counter)
478 {
479 	int val;
480 
481 	val = readl_relaxed(pmu->base + counter * 4 + COUNTER_CNTL);
482 
483 	return val & CNTL_OVER;
484 }
485 
486 static void ddr_perf_counter_clear(struct ddr_pmu *pmu, int counter)
487 {
488 	u8 reg = counter * 4 + COUNTER_CNTL;
489 	int val;
490 
491 	val = readl_relaxed(pmu->base + reg);
492 	val &= ~CNTL_CLEAR;
493 	writel(val, pmu->base + reg);
494 
495 	val |= CNTL_CLEAR;
496 	writel(val, pmu->base + reg);
497 }
498 
499 static void ddr_perf_event_update(struct perf_event *event)
500 {
501 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
502 	struct hw_perf_event *hwc = &event->hw;
503 	u64 new_raw_count;
504 	int counter = hwc->idx;
505 	int ret;
506 
507 	new_raw_count = ddr_perf_read_counter(pmu, counter);
508 	/* Remove the bias applied in ddr_perf_counter_enable(). */
509 	if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER_ENHANCED) {
510 		if (counter == EVENT_CYCLES_COUNTER)
511 			new_raw_count &= CYCLES_COUNTER_MASK;
512 	}
513 
514 	local64_add(new_raw_count, &event->count);
515 
516 	/*
517 	 * For legacy SoCs: event counter continue counting when overflow,
518 	 *                  no need to clear the counter.
519 	 * For new SoCs: event counter stop counting when overflow, need
520 	 *               clear counter to let it count again.
521 	 */
522 	if (counter != EVENT_CYCLES_COUNTER) {
523 		ret = ddr_perf_counter_overflow(pmu, counter);
524 		if (ret)
525 			dev_warn_ratelimited(pmu->dev,  "events lost due to counter overflow (config 0x%llx)\n",
526 					     event->attr.config);
527 	}
528 
529 	/* clear counter every time for both cycle counter and event counter */
530 	ddr_perf_counter_clear(pmu, counter);
531 }
532 
533 static void ddr_perf_event_start(struct perf_event *event, int flags)
534 {
535 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
536 	struct hw_perf_event *hwc = &event->hw;
537 	int counter = hwc->idx;
538 
539 	local64_set(&hwc->prev_count, 0);
540 
541 	ddr_perf_counter_enable(pmu, event->attr.config, counter, true);
542 
543 	if (!pmu->active_counter++)
544 		ddr_perf_counter_enable(pmu, EVENT_CYCLES_ID,
545 			EVENT_CYCLES_COUNTER, true);
546 
547 	hwc->state = 0;
548 }
549 
550 static int ddr_perf_event_add(struct perf_event *event, int flags)
551 {
552 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
553 	struct hw_perf_event *hwc = &event->hw;
554 	int counter;
555 	int cfg = event->attr.config;
556 	int cfg1 = event->attr.config1;
557 	int cfg2 = event->attr.config2;
558 
559 	if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER) {
560 		int i;
561 
562 		for (i = 1; i < NUM_COUNTERS; i++) {
563 			if (pmu->events[i] &&
564 			    !ddr_perf_filters_compatible(event, pmu->events[i]))
565 				return -EINVAL;
566 		}
567 
568 		if (ddr_perf_is_filtered(event)) {
569 			/* revert axi id masking(axi_mask) value */
570 			cfg1 ^= AXI_MASKING_REVERT;
571 			writel(cfg1, pmu->base + COUNTER_DPCR1);
572 		}
573 	}
574 
575 	counter = ddr_perf_alloc_counter(pmu, cfg);
576 	if (counter < 0) {
577 		dev_dbg(pmu->dev, "There are not enough counters\n");
578 		return -EOPNOTSUPP;
579 	}
580 
581 	if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_PORT_CHANNEL_FILTER) {
582 		if (ddr_perf_is_filtered(event)) {
583 			/* revert axi id masking(axi_mask) value */
584 			cfg1 ^= AXI_MASKING_REVERT;
585 			writel(cfg1, pmu->base + COUNTER_MASK_COMP + ((counter - 1) << 4));
586 
587 			if (cfg == 0x41) {
588 				/* revert axi read channel(axi_channel) value */
589 				cfg2 ^= READ_CHANNEL_REVERT;
590 				cfg2 |= FIELD_PREP(READ_PORT_MASK, cfg2);
591 			} else {
592 				/* revert axi write channel(axi_channel) value */
593 				cfg2 ^= WRITE_CHANNEL_REVERT;
594 				cfg2 |= FIELD_PREP(WRITE_PORT_MASK, cfg2);
595 			}
596 
597 			writel(cfg2, pmu->base + COUNTER_MUX_CNTL + ((counter - 1) << 4));
598 		}
599 	}
600 
601 	pmu->events[counter] = event;
602 	hwc->idx = counter;
603 
604 	hwc->state |= PERF_HES_STOPPED;
605 
606 	if (flags & PERF_EF_START)
607 		ddr_perf_event_start(event, flags);
608 
609 	return 0;
610 }
611 
612 static void ddr_perf_event_stop(struct perf_event *event, int flags)
613 {
614 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
615 	struct hw_perf_event *hwc = &event->hw;
616 	int counter = hwc->idx;
617 
618 	ddr_perf_counter_enable(pmu, event->attr.config, counter, false);
619 	ddr_perf_event_update(event);
620 
621 	if (!--pmu->active_counter)
622 		ddr_perf_counter_enable(pmu, EVENT_CYCLES_ID,
623 			EVENT_CYCLES_COUNTER, false);
624 
625 	hwc->state |= PERF_HES_STOPPED;
626 }
627 
628 static void ddr_perf_event_del(struct perf_event *event, int flags)
629 {
630 	struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
631 	struct hw_perf_event *hwc = &event->hw;
632 	int counter = hwc->idx;
633 
634 	ddr_perf_event_stop(event, PERF_EF_UPDATE);
635 
636 	ddr_perf_free_counter(pmu, counter);
637 	hwc->idx = -1;
638 }
639 
640 static void ddr_perf_pmu_enable(struct pmu *pmu)
641 {
642 }
643 
644 static void ddr_perf_pmu_disable(struct pmu *pmu)
645 {
646 }
647 
648 static int ddr_perf_init(struct ddr_pmu *pmu, void __iomem *base,
649 			 struct device *dev)
650 {
651 	*pmu = (struct ddr_pmu) {
652 		.pmu = (struct pmu) {
653 			.module	      = THIS_MODULE,
654 			.capabilities = PERF_PMU_CAP_NO_EXCLUDE,
655 			.task_ctx_nr = perf_invalid_context,
656 			.attr_groups = attr_groups,
657 			.event_init  = ddr_perf_event_init,
658 			.add	     = ddr_perf_event_add,
659 			.del	     = ddr_perf_event_del,
660 			.start	     = ddr_perf_event_start,
661 			.stop	     = ddr_perf_event_stop,
662 			.read	     = ddr_perf_event_update,
663 			.pmu_enable  = ddr_perf_pmu_enable,
664 			.pmu_disable = ddr_perf_pmu_disable,
665 		},
666 		.base = base,
667 		.dev = dev,
668 	};
669 
670 	pmu->id = ida_alloc(&ddr_ida, GFP_KERNEL);
671 	return pmu->id;
672 }
673 
674 static irqreturn_t ddr_perf_irq_handler(int irq, void *p)
675 {
676 	int i;
677 	struct ddr_pmu *pmu = (struct ddr_pmu *) p;
678 	struct perf_event *event;
679 
680 	/* all counter will stop if cycle counter disabled */
681 	ddr_perf_counter_enable(pmu,
682 			      EVENT_CYCLES_ID,
683 			      EVENT_CYCLES_COUNTER,
684 			      false);
685 	/*
686 	 * When the cycle counter overflows, all counters are stopped,
687 	 * and an IRQ is raised. If any other counter overflows, it
688 	 * continues counting, and no IRQ is raised. But for new SoCs,
689 	 * such as i.MX8MP, event counter would stop when overflow, so
690 	 * we need use cycle counter to stop overflow of event counter.
691 	 *
692 	 * Cycles occur at least 4 times as often as other events, so we
693 	 * can update all events on a cycle counter overflow and not
694 	 * lose events.
695 	 *
696 	 */
697 	for (i = 0; i < NUM_COUNTERS; i++) {
698 
699 		if (!pmu->events[i])
700 			continue;
701 
702 		event = pmu->events[i];
703 
704 		ddr_perf_event_update(event);
705 	}
706 
707 	ddr_perf_counter_enable(pmu,
708 			      EVENT_CYCLES_ID,
709 			      EVENT_CYCLES_COUNTER,
710 			      true);
711 
712 	return IRQ_HANDLED;
713 }
714 
715 static int ddr_perf_offline_cpu(unsigned int cpu, struct hlist_node *node)
716 {
717 	struct ddr_pmu *pmu = hlist_entry_safe(node, struct ddr_pmu, node);
718 	int target;
719 
720 	if (cpu != pmu->cpu)
721 		return 0;
722 
723 	target = cpumask_any_but(cpu_online_mask, cpu);
724 	if (target >= nr_cpu_ids)
725 		return 0;
726 
727 	perf_pmu_migrate_context(&pmu->pmu, cpu, target);
728 	pmu->cpu = target;
729 
730 	WARN_ON(irq_set_affinity(pmu->irq, cpumask_of(pmu->cpu)));
731 
732 	return 0;
733 }
734 
735 static int ddr_perf_probe(struct platform_device *pdev)
736 {
737 	struct ddr_pmu *pmu;
738 	struct device_node *np;
739 	void __iomem *base;
740 	char *name;
741 	int num;
742 	int ret;
743 	int irq;
744 
745 	base = devm_platform_ioremap_resource(pdev, 0);
746 	if (IS_ERR(base))
747 		return PTR_ERR(base);
748 
749 	np = pdev->dev.of_node;
750 
751 	pmu = devm_kzalloc(&pdev->dev, sizeof(*pmu), GFP_KERNEL);
752 	if (!pmu)
753 		return -ENOMEM;
754 
755 	num = ddr_perf_init(pmu, base, &pdev->dev);
756 
757 	platform_set_drvdata(pdev, pmu);
758 
759 	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, DDR_PERF_DEV_NAME "%d",
760 			      num);
761 	if (!name) {
762 		ret = -ENOMEM;
763 		goto cpuhp_state_err;
764 	}
765 
766 	pmu->devtype_data = of_device_get_match_data(&pdev->dev);
767 
768 	pmu->cpu = raw_smp_processor_id();
769 	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
770 				      DDR_CPUHP_CB_NAME,
771 				      NULL,
772 				      ddr_perf_offline_cpu);
773 
774 	if (ret < 0) {
775 		dev_err(&pdev->dev, "cpuhp_setup_state_multi failed\n");
776 		goto cpuhp_state_err;
777 	}
778 
779 	pmu->cpuhp_state = ret;
780 
781 	/* Register the pmu instance for cpu hotplug */
782 	ret = cpuhp_state_add_instance_nocalls(pmu->cpuhp_state, &pmu->node);
783 	if (ret) {
784 		dev_err(&pdev->dev, "Error %d registering hotplug\n", ret);
785 		goto cpuhp_instance_err;
786 	}
787 
788 	/* Request irq */
789 	irq = of_irq_get(np, 0);
790 	if (irq < 0) {
791 		dev_err(&pdev->dev, "Failed to get irq: %d", irq);
792 		ret = irq;
793 		goto ddr_perf_err;
794 	}
795 
796 	ret = devm_request_irq(&pdev->dev, irq,
797 					ddr_perf_irq_handler,
798 					IRQF_NOBALANCING | IRQF_NO_THREAD,
799 					DDR_CPUHP_CB_NAME,
800 					pmu);
801 	if (ret < 0) {
802 		dev_err(&pdev->dev, "Request irq failed: %d", ret);
803 		goto ddr_perf_err;
804 	}
805 
806 	pmu->irq = irq;
807 	ret = irq_set_affinity(pmu->irq, cpumask_of(pmu->cpu));
808 	if (ret) {
809 		dev_err(pmu->dev, "Failed to set interrupt affinity!\n");
810 		goto ddr_perf_err;
811 	}
812 
813 	ret = perf_pmu_register(&pmu->pmu, name, -1);
814 	if (ret)
815 		goto ddr_perf_err;
816 
817 	return 0;
818 
819 ddr_perf_err:
820 	cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
821 cpuhp_instance_err:
822 	cpuhp_remove_multi_state(pmu->cpuhp_state);
823 cpuhp_state_err:
824 	ida_free(&ddr_ida, pmu->id);
825 	dev_warn(&pdev->dev, "i.MX8 DDR Perf PMU failed (%d), disabled\n", ret);
826 	return ret;
827 }
828 
829 static void ddr_perf_remove(struct platform_device *pdev)
830 {
831 	struct ddr_pmu *pmu = platform_get_drvdata(pdev);
832 
833 	cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
834 	cpuhp_remove_multi_state(pmu->cpuhp_state);
835 
836 	perf_pmu_unregister(&pmu->pmu);
837 
838 	ida_free(&ddr_ida, pmu->id);
839 }
840 
841 static struct platform_driver imx_ddr_pmu_driver = {
842 	.driver         = {
843 		.name   = "imx-ddr-pmu",
844 		.of_match_table = imx_ddr_pmu_dt_ids,
845 		.suppress_bind_attrs = true,
846 	},
847 	.probe          = ddr_perf_probe,
848 	.remove_new     = ddr_perf_remove,
849 };
850 
851 module_platform_driver(imx_ddr_pmu_driver);
852 MODULE_LICENSE("GPL v2");
853