xref: /openbmc/linux/drivers/perf/arm_smmuv3_pmu.c (revision bb3982b4)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 /*
4  * This driver adds support for perf events to use the Performance
5  * Monitor Counter Groups (PMCG) associated with an SMMUv3 node
6  * to monitor that node.
7  *
8  * SMMUv3 PMCG devices are named as smmuv3_pmcg_<phys_addr_page> where
9  * <phys_addr_page> is the physical page address of the SMMU PMCG wrapped
10  * to 4K boundary. For example, the PMCG at 0xff88840000 is named
11  * smmuv3_pmcg_ff88840
12  *
13  * Filtering by stream id is done by specifying filtering parameters
14  * with the event. options are:
15  *   filter_enable    - 0 = no filtering, 1 = filtering enabled
16  *   filter_span      - 0 = exact match, 1 = pattern match
17  *   filter_stream_id - pattern to filter against
18  *
19  * To match a partial StreamID where the X most-significant bits must match
20  * but the Y least-significant bits might differ, STREAMID is programmed
21  * with a value that contains:
22  *  STREAMID[Y - 1] == 0.
23  *  STREAMID[Y - 2:0] == 1 (where Y > 1).
24  * The remainder of implemented bits of STREAMID (X bits, from bit Y upwards)
25  * contain a value to match from the corresponding bits of event StreamID.
26  *
27  * Example: perf stat -e smmuv3_pmcg_ff88840/transaction,filter_enable=1,
28  *                    filter_span=1,filter_stream_id=0x42/ -a netperf
29  * Applies filter pattern 0x42 to transaction events, which means events
30  * matching stream ids 0x42 and 0x43 are counted. Further filtering
31  * information is available in the SMMU documentation.
32  *
33  * SMMU events are not attributable to a CPU, so task mode and sampling
34  * are not supported.
35  */
36 
37 #include <linux/acpi.h>
38 #include <linux/acpi_iort.h>
39 #include <linux/bitfield.h>
40 #include <linux/bitops.h>
41 #include <linux/cpuhotplug.h>
42 #include <linux/cpumask.h>
43 #include <linux/device.h>
44 #include <linux/errno.h>
45 #include <linux/interrupt.h>
46 #include <linux/irq.h>
47 #include <linux/kernel.h>
48 #include <linux/list.h>
49 #include <linux/msi.h>
50 #include <linux/perf_event.h>
51 #include <linux/platform_device.h>
52 #include <linux/smp.h>
53 #include <linux/sysfs.h>
54 #include <linux/types.h>
55 
56 #define SMMU_PMCG_EVCNTR0               0x0
57 #define SMMU_PMCG_EVCNTR(n, stride)     (SMMU_PMCG_EVCNTR0 + (n) * (stride))
58 #define SMMU_PMCG_EVTYPER0              0x400
59 #define SMMU_PMCG_EVTYPER(n)            (SMMU_PMCG_EVTYPER0 + (n) * 4)
60 #define SMMU_PMCG_SID_SPAN_SHIFT        29
61 #define SMMU_PMCG_SMR0                  0xA00
62 #define SMMU_PMCG_SMR(n)                (SMMU_PMCG_SMR0 + (n) * 4)
63 #define SMMU_PMCG_CNTENSET0             0xC00
64 #define SMMU_PMCG_CNTENCLR0             0xC20
65 #define SMMU_PMCG_INTENSET0             0xC40
66 #define SMMU_PMCG_INTENCLR0             0xC60
67 #define SMMU_PMCG_OVSCLR0               0xC80
68 #define SMMU_PMCG_OVSSET0               0xCC0
69 #define SMMU_PMCG_CFGR                  0xE00
70 #define SMMU_PMCG_CFGR_SID_FILTER_TYPE  BIT(23)
71 #define SMMU_PMCG_CFGR_MSI              BIT(21)
72 #define SMMU_PMCG_CFGR_RELOC_CTRS       BIT(20)
73 #define SMMU_PMCG_CFGR_SIZE             GENMASK(13, 8)
74 #define SMMU_PMCG_CFGR_NCTR             GENMASK(5, 0)
75 #define SMMU_PMCG_CR                    0xE04
76 #define SMMU_PMCG_CR_ENABLE             BIT(0)
77 #define SMMU_PMCG_CEID0                 0xE20
78 #define SMMU_PMCG_CEID1                 0xE28
79 #define SMMU_PMCG_IRQ_CTRL              0xE50
80 #define SMMU_PMCG_IRQ_CTRL_IRQEN        BIT(0)
81 #define SMMU_PMCG_IRQ_CFG0              0xE58
82 #define SMMU_PMCG_IRQ_CFG1              0xE60
83 #define SMMU_PMCG_IRQ_CFG2              0xE64
84 
85 /* MSI config fields */
86 #define MSI_CFG0_ADDR_MASK              GENMASK_ULL(51, 2)
87 #define MSI_CFG2_MEMATTR_DEVICE_nGnRE   0x1
88 
89 #define SMMU_PMCG_DEFAULT_FILTER_SPAN   1
90 #define SMMU_PMCG_DEFAULT_FILTER_SID    GENMASK(31, 0)
91 
92 #define SMMU_PMCG_MAX_COUNTERS          64
93 #define SMMU_PMCG_ARCH_MAX_EVENTS       128
94 
95 #define SMMU_PMCG_PA_SHIFT              12
96 
97 #define SMMU_PMCG_EVCNTR_RDONLY         BIT(0)
98 
99 static int cpuhp_state_num;
100 
101 struct smmu_pmu {
102 	struct hlist_node node;
103 	struct perf_event *events[SMMU_PMCG_MAX_COUNTERS];
104 	DECLARE_BITMAP(used_counters, SMMU_PMCG_MAX_COUNTERS);
105 	DECLARE_BITMAP(supported_events, SMMU_PMCG_ARCH_MAX_EVENTS);
106 	unsigned int irq;
107 	unsigned int on_cpu;
108 	struct pmu pmu;
109 	unsigned int num_counters;
110 	struct device *dev;
111 	void __iomem *reg_base;
112 	void __iomem *reloc_base;
113 	u64 counter_mask;
114 	u32 options;
115 	bool global_filter;
116 	u32 global_filter_span;
117 	u32 global_filter_sid;
118 };
119 
120 #define to_smmu_pmu(p) (container_of(p, struct smmu_pmu, pmu))
121 
122 #define SMMU_PMU_EVENT_ATTR_EXTRACTOR(_name, _config, _start, _end)        \
123 	static inline u32 get_##_name(struct perf_event *event)            \
124 	{                                                                  \
125 		return FIELD_GET(GENMASK_ULL(_end, _start),                \
126 				 event->attr._config);                     \
127 	}                                                                  \
128 
129 SMMU_PMU_EVENT_ATTR_EXTRACTOR(event, config, 0, 15);
130 SMMU_PMU_EVENT_ATTR_EXTRACTOR(filter_stream_id, config1, 0, 31);
131 SMMU_PMU_EVENT_ATTR_EXTRACTOR(filter_span, config1, 32, 32);
132 SMMU_PMU_EVENT_ATTR_EXTRACTOR(filter_enable, config1, 33, 33);
133 
134 static inline void smmu_pmu_enable(struct pmu *pmu)
135 {
136 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(pmu);
137 
138 	writel(SMMU_PMCG_IRQ_CTRL_IRQEN,
139 	       smmu_pmu->reg_base + SMMU_PMCG_IRQ_CTRL);
140 	writel(SMMU_PMCG_CR_ENABLE, smmu_pmu->reg_base + SMMU_PMCG_CR);
141 }
142 
143 static inline void smmu_pmu_disable(struct pmu *pmu)
144 {
145 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(pmu);
146 
147 	writel(0, smmu_pmu->reg_base + SMMU_PMCG_CR);
148 	writel(0, smmu_pmu->reg_base + SMMU_PMCG_IRQ_CTRL);
149 }
150 
151 static inline void smmu_pmu_counter_set_value(struct smmu_pmu *smmu_pmu,
152 					      u32 idx, u64 value)
153 {
154 	if (smmu_pmu->counter_mask & BIT(32))
155 		writeq(value, smmu_pmu->reloc_base + SMMU_PMCG_EVCNTR(idx, 8));
156 	else
157 		writel(value, smmu_pmu->reloc_base + SMMU_PMCG_EVCNTR(idx, 4));
158 }
159 
160 static inline u64 smmu_pmu_counter_get_value(struct smmu_pmu *smmu_pmu, u32 idx)
161 {
162 	u64 value;
163 
164 	if (smmu_pmu->counter_mask & BIT(32))
165 		value = readq(smmu_pmu->reloc_base + SMMU_PMCG_EVCNTR(idx, 8));
166 	else
167 		value = readl(smmu_pmu->reloc_base + SMMU_PMCG_EVCNTR(idx, 4));
168 
169 	return value;
170 }
171 
172 static inline void smmu_pmu_counter_enable(struct smmu_pmu *smmu_pmu, u32 idx)
173 {
174 	writeq(BIT(idx), smmu_pmu->reg_base + SMMU_PMCG_CNTENSET0);
175 }
176 
177 static inline void smmu_pmu_counter_disable(struct smmu_pmu *smmu_pmu, u32 idx)
178 {
179 	writeq(BIT(idx), smmu_pmu->reg_base + SMMU_PMCG_CNTENCLR0);
180 }
181 
182 static inline void smmu_pmu_interrupt_enable(struct smmu_pmu *smmu_pmu, u32 idx)
183 {
184 	writeq(BIT(idx), smmu_pmu->reg_base + SMMU_PMCG_INTENSET0);
185 }
186 
187 static inline void smmu_pmu_interrupt_disable(struct smmu_pmu *smmu_pmu,
188 					      u32 idx)
189 {
190 	writeq(BIT(idx), smmu_pmu->reg_base + SMMU_PMCG_INTENCLR0);
191 }
192 
193 static inline void smmu_pmu_set_evtyper(struct smmu_pmu *smmu_pmu, u32 idx,
194 					u32 val)
195 {
196 	writel(val, smmu_pmu->reg_base + SMMU_PMCG_EVTYPER(idx));
197 }
198 
199 static inline void smmu_pmu_set_smr(struct smmu_pmu *smmu_pmu, u32 idx, u32 val)
200 {
201 	writel(val, smmu_pmu->reg_base + SMMU_PMCG_SMR(idx));
202 }
203 
204 static void smmu_pmu_event_update(struct perf_event *event)
205 {
206 	struct hw_perf_event *hwc = &event->hw;
207 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
208 	u64 delta, prev, now;
209 	u32 idx = hwc->idx;
210 
211 	do {
212 		prev = local64_read(&hwc->prev_count);
213 		now = smmu_pmu_counter_get_value(smmu_pmu, idx);
214 	} while (local64_cmpxchg(&hwc->prev_count, prev, now) != prev);
215 
216 	/* handle overflow. */
217 	delta = now - prev;
218 	delta &= smmu_pmu->counter_mask;
219 
220 	local64_add(delta, &event->count);
221 }
222 
223 static void smmu_pmu_set_period(struct smmu_pmu *smmu_pmu,
224 				struct hw_perf_event *hwc)
225 {
226 	u32 idx = hwc->idx;
227 	u64 new;
228 
229 	if (smmu_pmu->options & SMMU_PMCG_EVCNTR_RDONLY) {
230 		/*
231 		 * On platforms that require this quirk, if the counter starts
232 		 * at < half_counter value and wraps, the current logic of
233 		 * handling the overflow may not work. It is expected that,
234 		 * those platforms will have full 64 counter bits implemented
235 		 * so that such a possibility is remote(eg: HiSilicon HIP08).
236 		 */
237 		new = smmu_pmu_counter_get_value(smmu_pmu, idx);
238 	} else {
239 		/*
240 		 * We limit the max period to half the max counter value
241 		 * of the counter size, so that even in the case of extreme
242 		 * interrupt latency the counter will (hopefully) not wrap
243 		 * past its initial value.
244 		 */
245 		new = smmu_pmu->counter_mask >> 1;
246 		smmu_pmu_counter_set_value(smmu_pmu, idx, new);
247 	}
248 
249 	local64_set(&hwc->prev_count, new);
250 }
251 
252 static void smmu_pmu_set_event_filter(struct perf_event *event,
253 				      int idx, u32 span, u32 sid)
254 {
255 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
256 	u32 evtyper;
257 
258 	evtyper = get_event(event) | span << SMMU_PMCG_SID_SPAN_SHIFT;
259 	smmu_pmu_set_evtyper(smmu_pmu, idx, evtyper);
260 	smmu_pmu_set_smr(smmu_pmu, idx, sid);
261 }
262 
263 static int smmu_pmu_apply_event_filter(struct smmu_pmu *smmu_pmu,
264 				       struct perf_event *event, int idx)
265 {
266 	u32 span, sid;
267 	unsigned int num_ctrs = smmu_pmu->num_counters;
268 	bool filter_en = !!get_filter_enable(event);
269 
270 	span = filter_en ? get_filter_span(event) :
271 			   SMMU_PMCG_DEFAULT_FILTER_SPAN;
272 	sid = filter_en ? get_filter_stream_id(event) :
273 			   SMMU_PMCG_DEFAULT_FILTER_SID;
274 
275 	/* Support individual filter settings */
276 	if (!smmu_pmu->global_filter) {
277 		smmu_pmu_set_event_filter(event, idx, span, sid);
278 		return 0;
279 	}
280 
281 	/* Requested settings same as current global settings*/
282 	if (span == smmu_pmu->global_filter_span &&
283 	    sid == smmu_pmu->global_filter_sid)
284 		return 0;
285 
286 	if (!bitmap_empty(smmu_pmu->used_counters, num_ctrs))
287 		return -EAGAIN;
288 
289 	smmu_pmu_set_event_filter(event, 0, span, sid);
290 	smmu_pmu->global_filter_span = span;
291 	smmu_pmu->global_filter_sid = sid;
292 	return 0;
293 }
294 
295 static int smmu_pmu_get_event_idx(struct smmu_pmu *smmu_pmu,
296 				  struct perf_event *event)
297 {
298 	int idx, err;
299 	unsigned int num_ctrs = smmu_pmu->num_counters;
300 
301 	idx = find_first_zero_bit(smmu_pmu->used_counters, num_ctrs);
302 	if (idx == num_ctrs)
303 		/* The counters are all in use. */
304 		return -EAGAIN;
305 
306 	err = smmu_pmu_apply_event_filter(smmu_pmu, event, idx);
307 	if (err)
308 		return err;
309 
310 	set_bit(idx, smmu_pmu->used_counters);
311 
312 	return idx;
313 }
314 
315 /*
316  * Implementation of abstract pmu functionality required by
317  * the core perf events code.
318  */
319 
320 static int smmu_pmu_event_init(struct perf_event *event)
321 {
322 	struct hw_perf_event *hwc = &event->hw;
323 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
324 	struct device *dev = smmu_pmu->dev;
325 	struct perf_event *sibling;
326 	u16 event_id;
327 
328 	if (event->attr.type != event->pmu->type)
329 		return -ENOENT;
330 
331 	if (hwc->sample_period) {
332 		dev_dbg(dev, "Sampling not supported\n");
333 		return -EOPNOTSUPP;
334 	}
335 
336 	if (event->cpu < 0) {
337 		dev_dbg(dev, "Per-task mode not supported\n");
338 		return -EOPNOTSUPP;
339 	}
340 
341 	/* Verify specified event is supported on this PMU */
342 	event_id = get_event(event);
343 	if (event_id < SMMU_PMCG_ARCH_MAX_EVENTS &&
344 	    (!test_bit(event_id, smmu_pmu->supported_events))) {
345 		dev_dbg(dev, "Invalid event %d for this PMU\n", event_id);
346 		return -EINVAL;
347 	}
348 
349 	/* Don't allow groups with mixed PMUs, except for s/w events */
350 	if (event->group_leader->pmu != event->pmu &&
351 	    !is_software_event(event->group_leader)) {
352 		dev_dbg(dev, "Can't create mixed PMU group\n");
353 		return -EINVAL;
354 	}
355 
356 	for_each_sibling_event(sibling, event->group_leader) {
357 		if (sibling->pmu != event->pmu &&
358 		    !is_software_event(sibling)) {
359 			dev_dbg(dev, "Can't create mixed PMU group\n");
360 			return -EINVAL;
361 		}
362 	}
363 
364 	hwc->idx = -1;
365 
366 	/*
367 	 * Ensure all events are on the same cpu so all events are in the
368 	 * same cpu context, to avoid races on pmu_enable etc.
369 	 */
370 	event->cpu = smmu_pmu->on_cpu;
371 
372 	return 0;
373 }
374 
375 static void smmu_pmu_event_start(struct perf_event *event, int flags)
376 {
377 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
378 	struct hw_perf_event *hwc = &event->hw;
379 	int idx = hwc->idx;
380 
381 	hwc->state = 0;
382 
383 	smmu_pmu_set_period(smmu_pmu, hwc);
384 
385 	smmu_pmu_counter_enable(smmu_pmu, idx);
386 }
387 
388 static void smmu_pmu_event_stop(struct perf_event *event, int flags)
389 {
390 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
391 	struct hw_perf_event *hwc = &event->hw;
392 	int idx = hwc->idx;
393 
394 	if (hwc->state & PERF_HES_STOPPED)
395 		return;
396 
397 	smmu_pmu_counter_disable(smmu_pmu, idx);
398 	/* As the counter gets updated on _start, ignore PERF_EF_UPDATE */
399 	smmu_pmu_event_update(event);
400 	hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
401 }
402 
403 static int smmu_pmu_event_add(struct perf_event *event, int flags)
404 {
405 	struct hw_perf_event *hwc = &event->hw;
406 	int idx;
407 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
408 
409 	idx = smmu_pmu_get_event_idx(smmu_pmu, event);
410 	if (idx < 0)
411 		return idx;
412 
413 	hwc->idx = idx;
414 	hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
415 	smmu_pmu->events[idx] = event;
416 	local64_set(&hwc->prev_count, 0);
417 
418 	smmu_pmu_interrupt_enable(smmu_pmu, idx);
419 
420 	if (flags & PERF_EF_START)
421 		smmu_pmu_event_start(event, flags);
422 
423 	/* Propagate changes to the userspace mapping. */
424 	perf_event_update_userpage(event);
425 
426 	return 0;
427 }
428 
429 static void smmu_pmu_event_del(struct perf_event *event, int flags)
430 {
431 	struct hw_perf_event *hwc = &event->hw;
432 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
433 	int idx = hwc->idx;
434 
435 	smmu_pmu_event_stop(event, flags | PERF_EF_UPDATE);
436 	smmu_pmu_interrupt_disable(smmu_pmu, idx);
437 	smmu_pmu->events[idx] = NULL;
438 	clear_bit(idx, smmu_pmu->used_counters);
439 
440 	perf_event_update_userpage(event);
441 }
442 
443 static void smmu_pmu_event_read(struct perf_event *event)
444 {
445 	smmu_pmu_event_update(event);
446 }
447 
448 /* cpumask */
449 
450 static ssize_t smmu_pmu_cpumask_show(struct device *dev,
451 				     struct device_attribute *attr,
452 				     char *buf)
453 {
454 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(dev_get_drvdata(dev));
455 
456 	return cpumap_print_to_pagebuf(true, buf, cpumask_of(smmu_pmu->on_cpu));
457 }
458 
459 static struct device_attribute smmu_pmu_cpumask_attr =
460 		__ATTR(cpumask, 0444, smmu_pmu_cpumask_show, NULL);
461 
462 static struct attribute *smmu_pmu_cpumask_attrs[] = {
463 	&smmu_pmu_cpumask_attr.attr,
464 	NULL
465 };
466 
467 static struct attribute_group smmu_pmu_cpumask_group = {
468 	.attrs = smmu_pmu_cpumask_attrs,
469 };
470 
471 /* Events */
472 
473 static ssize_t smmu_pmu_event_show(struct device *dev,
474 				   struct device_attribute *attr, char *page)
475 {
476 	struct perf_pmu_events_attr *pmu_attr;
477 
478 	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
479 
480 	return sprintf(page, "event=0x%02llx\n", pmu_attr->id);
481 }
482 
483 #define SMMU_EVENT_ATTR(name, config) \
484 	PMU_EVENT_ATTR(name, smmu_event_attr_##name, \
485 		       config, smmu_pmu_event_show)
486 SMMU_EVENT_ATTR(cycles, 0);
487 SMMU_EVENT_ATTR(transaction, 1);
488 SMMU_EVENT_ATTR(tlb_miss, 2);
489 SMMU_EVENT_ATTR(config_cache_miss, 3);
490 SMMU_EVENT_ATTR(trans_table_walk_access, 4);
491 SMMU_EVENT_ATTR(config_struct_access, 5);
492 SMMU_EVENT_ATTR(pcie_ats_trans_rq, 6);
493 SMMU_EVENT_ATTR(pcie_ats_trans_passed, 7);
494 
495 static struct attribute *smmu_pmu_events[] = {
496 	&smmu_event_attr_cycles.attr.attr,
497 	&smmu_event_attr_transaction.attr.attr,
498 	&smmu_event_attr_tlb_miss.attr.attr,
499 	&smmu_event_attr_config_cache_miss.attr.attr,
500 	&smmu_event_attr_trans_table_walk_access.attr.attr,
501 	&smmu_event_attr_config_struct_access.attr.attr,
502 	&smmu_event_attr_pcie_ats_trans_rq.attr.attr,
503 	&smmu_event_attr_pcie_ats_trans_passed.attr.attr,
504 	NULL
505 };
506 
507 static umode_t smmu_pmu_event_is_visible(struct kobject *kobj,
508 					 struct attribute *attr, int unused)
509 {
510 	struct device *dev = kobj_to_dev(kobj);
511 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(dev_get_drvdata(dev));
512 	struct perf_pmu_events_attr *pmu_attr;
513 
514 	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr.attr);
515 
516 	if (test_bit(pmu_attr->id, smmu_pmu->supported_events))
517 		return attr->mode;
518 
519 	return 0;
520 }
521 
522 static struct attribute_group smmu_pmu_events_group = {
523 	.name = "events",
524 	.attrs = smmu_pmu_events,
525 	.is_visible = smmu_pmu_event_is_visible,
526 };
527 
528 /* Formats */
529 PMU_FORMAT_ATTR(event,		   "config:0-15");
530 PMU_FORMAT_ATTR(filter_stream_id,  "config1:0-31");
531 PMU_FORMAT_ATTR(filter_span,	   "config1:32");
532 PMU_FORMAT_ATTR(filter_enable,	   "config1:33");
533 
534 static struct attribute *smmu_pmu_formats[] = {
535 	&format_attr_event.attr,
536 	&format_attr_filter_stream_id.attr,
537 	&format_attr_filter_span.attr,
538 	&format_attr_filter_enable.attr,
539 	NULL
540 };
541 
542 static struct attribute_group smmu_pmu_format_group = {
543 	.name = "format",
544 	.attrs = smmu_pmu_formats,
545 };
546 
547 static const struct attribute_group *smmu_pmu_attr_grps[] = {
548 	&smmu_pmu_cpumask_group,
549 	&smmu_pmu_events_group,
550 	&smmu_pmu_format_group,
551 	NULL
552 };
553 
554 /*
555  * Generic device handlers
556  */
557 
558 static int smmu_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
559 {
560 	struct smmu_pmu *smmu_pmu;
561 	unsigned int target;
562 
563 	smmu_pmu = hlist_entry_safe(node, struct smmu_pmu, node);
564 	if (cpu != smmu_pmu->on_cpu)
565 		return 0;
566 
567 	target = cpumask_any_but(cpu_online_mask, cpu);
568 	if (target >= nr_cpu_ids)
569 		return 0;
570 
571 	perf_pmu_migrate_context(&smmu_pmu->pmu, cpu, target);
572 	smmu_pmu->on_cpu = target;
573 	WARN_ON(irq_set_affinity_hint(smmu_pmu->irq, cpumask_of(target)));
574 
575 	return 0;
576 }
577 
578 static irqreturn_t smmu_pmu_handle_irq(int irq_num, void *data)
579 {
580 	struct smmu_pmu *smmu_pmu = data;
581 	u64 ovsr;
582 	unsigned int idx;
583 
584 	ovsr = readq(smmu_pmu->reloc_base + SMMU_PMCG_OVSSET0);
585 	if (!ovsr)
586 		return IRQ_NONE;
587 
588 	writeq(ovsr, smmu_pmu->reloc_base + SMMU_PMCG_OVSCLR0);
589 
590 	for_each_set_bit(idx, (unsigned long *)&ovsr, smmu_pmu->num_counters) {
591 		struct perf_event *event = smmu_pmu->events[idx];
592 		struct hw_perf_event *hwc;
593 
594 		if (WARN_ON_ONCE(!event))
595 			continue;
596 
597 		smmu_pmu_event_update(event);
598 		hwc = &event->hw;
599 
600 		smmu_pmu_set_period(smmu_pmu, hwc);
601 	}
602 
603 	return IRQ_HANDLED;
604 }
605 
606 static void smmu_pmu_free_msis(void *data)
607 {
608 	struct device *dev = data;
609 
610 	platform_msi_domain_free_irqs(dev);
611 }
612 
613 static void smmu_pmu_write_msi_msg(struct msi_desc *desc, struct msi_msg *msg)
614 {
615 	phys_addr_t doorbell;
616 	struct device *dev = msi_desc_to_dev(desc);
617 	struct smmu_pmu *pmu = dev_get_drvdata(dev);
618 
619 	doorbell = (((u64)msg->address_hi) << 32) | msg->address_lo;
620 	doorbell &= MSI_CFG0_ADDR_MASK;
621 
622 	writeq_relaxed(doorbell, pmu->reg_base + SMMU_PMCG_IRQ_CFG0);
623 	writel_relaxed(msg->data, pmu->reg_base + SMMU_PMCG_IRQ_CFG1);
624 	writel_relaxed(MSI_CFG2_MEMATTR_DEVICE_nGnRE,
625 		       pmu->reg_base + SMMU_PMCG_IRQ_CFG2);
626 }
627 
628 static void smmu_pmu_setup_msi(struct smmu_pmu *pmu)
629 {
630 	struct msi_desc *desc;
631 	struct device *dev = pmu->dev;
632 	int ret;
633 
634 	/* Clear MSI address reg */
635 	writeq_relaxed(0, pmu->reg_base + SMMU_PMCG_IRQ_CFG0);
636 
637 	/* MSI supported or not */
638 	if (!(readl(pmu->reg_base + SMMU_PMCG_CFGR) & SMMU_PMCG_CFGR_MSI))
639 		return;
640 
641 	ret = platform_msi_domain_alloc_irqs(dev, 1, smmu_pmu_write_msi_msg);
642 	if (ret) {
643 		dev_warn(dev, "failed to allocate MSIs\n");
644 		return;
645 	}
646 
647 	desc = first_msi_entry(dev);
648 	if (desc)
649 		pmu->irq = desc->irq;
650 
651 	/* Add callback to free MSIs on teardown */
652 	devm_add_action(dev, smmu_pmu_free_msis, dev);
653 }
654 
655 static int smmu_pmu_setup_irq(struct smmu_pmu *pmu)
656 {
657 	unsigned long flags = IRQF_NOBALANCING | IRQF_SHARED | IRQF_NO_THREAD;
658 	int irq, ret = -ENXIO;
659 
660 	smmu_pmu_setup_msi(pmu);
661 
662 	irq = pmu->irq;
663 	if (irq)
664 		ret = devm_request_irq(pmu->dev, irq, smmu_pmu_handle_irq,
665 				       flags, "smmuv3-pmu", pmu);
666 	return ret;
667 }
668 
669 static void smmu_pmu_reset(struct smmu_pmu *smmu_pmu)
670 {
671 	u64 counter_present_mask = GENMASK_ULL(smmu_pmu->num_counters - 1, 0);
672 
673 	smmu_pmu_disable(&smmu_pmu->pmu);
674 
675 	/* Disable counter and interrupt */
676 	writeq_relaxed(counter_present_mask,
677 		       smmu_pmu->reg_base + SMMU_PMCG_CNTENCLR0);
678 	writeq_relaxed(counter_present_mask,
679 		       smmu_pmu->reg_base + SMMU_PMCG_INTENCLR0);
680 	writeq_relaxed(counter_present_mask,
681 		       smmu_pmu->reloc_base + SMMU_PMCG_OVSCLR0);
682 }
683 
684 static void smmu_pmu_get_acpi_options(struct smmu_pmu *smmu_pmu)
685 {
686 	u32 model;
687 
688 	model = *(u32 *)dev_get_platdata(smmu_pmu->dev);
689 
690 	switch (model) {
691 	case IORT_SMMU_V3_PMCG_HISI_HIP08:
692 		/* HiSilicon Erratum 162001800 */
693 		smmu_pmu->options |= SMMU_PMCG_EVCNTR_RDONLY;
694 		break;
695 	}
696 
697 	dev_notice(smmu_pmu->dev, "option mask 0x%x\n", smmu_pmu->options);
698 }
699 
700 static int smmu_pmu_probe(struct platform_device *pdev)
701 {
702 	struct smmu_pmu *smmu_pmu;
703 	struct resource *res_0, *res_1;
704 	u32 cfgr, reg_size;
705 	u64 ceid_64[2];
706 	int irq, err;
707 	char *name;
708 	struct device *dev = &pdev->dev;
709 
710 	smmu_pmu = devm_kzalloc(dev, sizeof(*smmu_pmu), GFP_KERNEL);
711 	if (!smmu_pmu)
712 		return -ENOMEM;
713 
714 	smmu_pmu->dev = dev;
715 	platform_set_drvdata(pdev, smmu_pmu);
716 
717 	smmu_pmu->pmu = (struct pmu) {
718 		.task_ctx_nr    = perf_invalid_context,
719 		.pmu_enable	= smmu_pmu_enable,
720 		.pmu_disable	= smmu_pmu_disable,
721 		.event_init	= smmu_pmu_event_init,
722 		.add		= smmu_pmu_event_add,
723 		.del		= smmu_pmu_event_del,
724 		.start		= smmu_pmu_event_start,
725 		.stop		= smmu_pmu_event_stop,
726 		.read		= smmu_pmu_event_read,
727 		.attr_groups	= smmu_pmu_attr_grps,
728 		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
729 	};
730 
731 	res_0 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
732 	smmu_pmu->reg_base = devm_ioremap_resource(dev, res_0);
733 	if (IS_ERR(smmu_pmu->reg_base))
734 		return PTR_ERR(smmu_pmu->reg_base);
735 
736 	cfgr = readl_relaxed(smmu_pmu->reg_base + SMMU_PMCG_CFGR);
737 
738 	/* Determine if page 1 is present */
739 	if (cfgr & SMMU_PMCG_CFGR_RELOC_CTRS) {
740 		res_1 = platform_get_resource(pdev, IORESOURCE_MEM, 1);
741 		smmu_pmu->reloc_base = devm_ioremap_resource(dev, res_1);
742 		if (IS_ERR(smmu_pmu->reloc_base))
743 			return PTR_ERR(smmu_pmu->reloc_base);
744 	} else {
745 		smmu_pmu->reloc_base = smmu_pmu->reg_base;
746 	}
747 
748 	irq = platform_get_irq(pdev, 0);
749 	if (irq > 0)
750 		smmu_pmu->irq = irq;
751 
752 	ceid_64[0] = readq_relaxed(smmu_pmu->reg_base + SMMU_PMCG_CEID0);
753 	ceid_64[1] = readq_relaxed(smmu_pmu->reg_base + SMMU_PMCG_CEID1);
754 	bitmap_from_arr32(smmu_pmu->supported_events, (u32 *)ceid_64,
755 			  SMMU_PMCG_ARCH_MAX_EVENTS);
756 
757 	smmu_pmu->num_counters = FIELD_GET(SMMU_PMCG_CFGR_NCTR, cfgr) + 1;
758 
759 	smmu_pmu->global_filter = !!(cfgr & SMMU_PMCG_CFGR_SID_FILTER_TYPE);
760 
761 	reg_size = FIELD_GET(SMMU_PMCG_CFGR_SIZE, cfgr);
762 	smmu_pmu->counter_mask = GENMASK_ULL(reg_size, 0);
763 
764 	smmu_pmu_reset(smmu_pmu);
765 
766 	err = smmu_pmu_setup_irq(smmu_pmu);
767 	if (err) {
768 		dev_err(dev, "Setup irq failed, PMU @%pa\n", &res_0->start);
769 		return err;
770 	}
771 
772 	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "smmuv3_pmcg_%llx",
773 			      (res_0->start) >> SMMU_PMCG_PA_SHIFT);
774 	if (!name) {
775 		dev_err(dev, "Create name failed, PMU @%pa\n", &res_0->start);
776 		return -EINVAL;
777 	}
778 
779 	smmu_pmu_get_acpi_options(smmu_pmu);
780 
781 	/* Pick one CPU to be the preferred one to use */
782 	smmu_pmu->on_cpu = raw_smp_processor_id();
783 	WARN_ON(irq_set_affinity_hint(smmu_pmu->irq,
784 				      cpumask_of(smmu_pmu->on_cpu)));
785 
786 	err = cpuhp_state_add_instance_nocalls(cpuhp_state_num,
787 					       &smmu_pmu->node);
788 	if (err) {
789 		dev_err(dev, "Error %d registering hotplug, PMU @%pa\n",
790 			err, &res_0->start);
791 		goto out_cpuhp_err;
792 	}
793 
794 	err = perf_pmu_register(&smmu_pmu->pmu, name, -1);
795 	if (err) {
796 		dev_err(dev, "Error %d registering PMU @%pa\n",
797 			err, &res_0->start);
798 		goto out_unregister;
799 	}
800 
801 	dev_info(dev, "Registered PMU @ %pa using %d counters with %s filter settings\n",
802 		 &res_0->start, smmu_pmu->num_counters,
803 		 smmu_pmu->global_filter ? "Global(Counter0)" :
804 		 "Individual");
805 
806 	return 0;
807 
808 out_unregister:
809 	cpuhp_state_remove_instance_nocalls(cpuhp_state_num, &smmu_pmu->node);
810 out_cpuhp_err:
811 	put_cpu();
812 	return err;
813 }
814 
815 static int smmu_pmu_remove(struct platform_device *pdev)
816 {
817 	struct smmu_pmu *smmu_pmu = platform_get_drvdata(pdev);
818 
819 	perf_pmu_unregister(&smmu_pmu->pmu);
820 	cpuhp_state_remove_instance_nocalls(cpuhp_state_num, &smmu_pmu->node);
821 
822 	return 0;
823 }
824 
825 static void smmu_pmu_shutdown(struct platform_device *pdev)
826 {
827 	struct smmu_pmu *smmu_pmu = platform_get_drvdata(pdev);
828 
829 	smmu_pmu_disable(&smmu_pmu->pmu);
830 }
831 
832 static struct platform_driver smmu_pmu_driver = {
833 	.driver = {
834 		.name = "arm-smmu-v3-pmcg",
835 	},
836 	.probe = smmu_pmu_probe,
837 	.remove = smmu_pmu_remove,
838 	.shutdown = smmu_pmu_shutdown,
839 };
840 
841 static int __init arm_smmu_pmu_init(void)
842 {
843 	cpuhp_state_num = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
844 						  "perf/arm/pmcg:online",
845 						  NULL,
846 						  smmu_pmu_offline_cpu);
847 	if (cpuhp_state_num < 0)
848 		return cpuhp_state_num;
849 
850 	return platform_driver_register(&smmu_pmu_driver);
851 }
852 module_init(arm_smmu_pmu_init);
853 
854 static void __exit arm_smmu_pmu_exit(void)
855 {
856 	platform_driver_unregister(&smmu_pmu_driver);
857 	cpuhp_remove_multi_state(cpuhp_state_num);
858 }
859 
860 module_exit(arm_smmu_pmu_exit);
861 
862 MODULE_DESCRIPTION("PMU driver for ARM SMMUv3 Performance Monitors Extension");
863 MODULE_AUTHOR("Neil Leeder <nleeder@codeaurora.org>");
864 MODULE_AUTHOR("Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>");
865 MODULE_LICENSE("GPL v2");
866