xref: /linux/tools/perf/arch/arm/util/cs-etm.c (revision 6e7fd890f1d6ac83805409e9c346240de2705584)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright(C) 2015 Linaro Limited. All rights reserved.
4  * Author: Mathieu Poirier <mathieu.poirier@linaro.org>
5  */
6 
7 #include <api/fs/fs.h>
8 #include <linux/bits.h>
9 #include <linux/bitops.h>
10 #include <linux/compiler.h>
11 #include <linux/coresight-pmu.h>
12 #include <linux/kernel.h>
13 #include <linux/log2.h>
14 #include <linux/string.h>
15 #include <linux/types.h>
16 #include <linux/zalloc.h>
17 
18 #include "cs-etm.h"
19 #include "../../../util/debug.h"
20 #include "../../../util/record.h"
21 #include "../../../util/auxtrace.h"
22 #include "../../../util/cpumap.h"
23 #include "../../../util/event.h"
24 #include "../../../util/evlist.h"
25 #include "../../../util/evsel.h"
26 #include "../../../util/perf_api_probe.h"
27 #include "../../../util/evsel_config.h"
28 #include "../../../util/pmus.h"
29 #include "../../../util/cs-etm.h"
30 #include <internal/lib.h> // page_size
31 #include "../../../util/session.h"
32 
33 #include <errno.h>
34 #include <stdlib.h>
35 #include <sys/stat.h>
36 
37 struct cs_etm_recording {
38 	struct auxtrace_record	itr;
39 	struct perf_pmu		*cs_etm_pmu;
40 	struct evlist		*evlist;
41 	bool			snapshot_mode;
42 	size_t			snapshot_size;
43 };
44 
45 static const char *metadata_etmv3_ro[CS_ETM_PRIV_MAX] = {
46 	[CS_ETM_ETMCCER]	= "mgmt/etmccer",
47 	[CS_ETM_ETMIDR]		= "mgmt/etmidr",
48 };
49 
50 static const char * const metadata_etmv4_ro[] = {
51 	[CS_ETMV4_TRCIDR0]		= "trcidr/trcidr0",
52 	[CS_ETMV4_TRCIDR1]		= "trcidr/trcidr1",
53 	[CS_ETMV4_TRCIDR2]		= "trcidr/trcidr2",
54 	[CS_ETMV4_TRCIDR8]		= "trcidr/trcidr8",
55 	[CS_ETMV4_TRCAUTHSTATUS]	= "mgmt/trcauthstatus",
56 	[CS_ETMV4_TS_SOURCE]		= "ts_source",
57 };
58 
59 static const char * const metadata_ete_ro[] = {
60 	[CS_ETE_TRCIDR0]		= "trcidr/trcidr0",
61 	[CS_ETE_TRCIDR1]		= "trcidr/trcidr1",
62 	[CS_ETE_TRCIDR2]		= "trcidr/trcidr2",
63 	[CS_ETE_TRCIDR8]		= "trcidr/trcidr8",
64 	[CS_ETE_TRCAUTHSTATUS]		= "mgmt/trcauthstatus",
65 	[CS_ETE_TRCDEVARCH]		= "mgmt/trcdevarch",
66 	[CS_ETE_TS_SOURCE]		= "ts_source",
67 };
68 
69 enum cs_etm_version { CS_NOT_PRESENT, CS_ETMV3, CS_ETMV4, CS_ETE };
70 
71 static bool cs_etm_is_ete(struct perf_pmu *cs_etm_pmu, struct perf_cpu cpu);
72 static int cs_etm_get_ro(struct perf_pmu *pmu, struct perf_cpu cpu, const char *path, __u64 *val);
73 static bool cs_etm_pmu_path_exists(struct perf_pmu *pmu, struct perf_cpu cpu, const char *path);
74 
75 static enum cs_etm_version cs_etm_get_version(struct perf_pmu *cs_etm_pmu,
76 					      struct perf_cpu cpu)
77 {
78 	if (cs_etm_is_ete(cs_etm_pmu, cpu))
79 		return CS_ETE;
80 	else if (cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR0]))
81 		return CS_ETMV4;
82 	else if (cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_etmv3_ro[CS_ETM_ETMCCER]))
83 		return CS_ETMV3;
84 
85 	return CS_NOT_PRESENT;
86 }
87 
88 static int cs_etm_validate_context_id(struct perf_pmu *cs_etm_pmu, struct evsel *evsel,
89 				      struct perf_cpu cpu)
90 {
91 	int err;
92 	__u64 val;
93 	u64 contextid = evsel->core.attr.config &
94 		(perf_pmu__format_bits(cs_etm_pmu, "contextid") |
95 		 perf_pmu__format_bits(cs_etm_pmu, "contextid1") |
96 		 perf_pmu__format_bits(cs_etm_pmu, "contextid2"));
97 
98 	if (!contextid)
99 		return 0;
100 
101 	/* Not supported in etmv3 */
102 	if (cs_etm_get_version(cs_etm_pmu, cpu) == CS_ETMV3) {
103 		pr_err("%s: contextid not supported in ETMv3, disable with %s/contextid=0/\n",
104 		       CORESIGHT_ETM_PMU_NAME, CORESIGHT_ETM_PMU_NAME);
105 		return -EINVAL;
106 	}
107 
108 	/* Get a handle on TRCIDR2 */
109 	err = cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR2], &val);
110 	if (err)
111 		return err;
112 
113 	if (contextid &
114 	    perf_pmu__format_bits(cs_etm_pmu, "contextid1")) {
115 		/*
116 		 * TRCIDR2.CIDSIZE, bit [9-5], indicates whether contextID
117 		 * tracing is supported:
118 		 *  0b00000 Context ID tracing is not supported.
119 		 *  0b00100 Maximum of 32-bit Context ID size.
120 		 *  All other values are reserved.
121 		 */
122 		if (BMVAL(val, 5, 9) != 0x4) {
123 			pr_err("%s: CONTEXTIDR_EL1 isn't supported, disable with %s/contextid1=0/\n",
124 			       CORESIGHT_ETM_PMU_NAME, CORESIGHT_ETM_PMU_NAME);
125 			return -EINVAL;
126 		}
127 	}
128 
129 	if (contextid &
130 	    perf_pmu__format_bits(cs_etm_pmu, "contextid2")) {
131 		/*
132 		 * TRCIDR2.VMIDOPT[30:29] != 0 and
133 		 * TRCIDR2.VMIDSIZE[14:10] == 0b00100 (32bit virtual contextid)
134 		 * We can't support CONTEXTIDR in VMID if the size of the
135 		 * virtual context id is < 32bit.
136 		 * Any value of VMIDSIZE >= 4 (i.e, > 32bit) is fine for us.
137 		 */
138 		if (!BMVAL(val, 29, 30) || BMVAL(val, 10, 14) < 4) {
139 			pr_err("%s: CONTEXTIDR_EL2 isn't supported, disable with %s/contextid2=0/\n",
140 			       CORESIGHT_ETM_PMU_NAME, CORESIGHT_ETM_PMU_NAME);
141 			return -EINVAL;
142 		}
143 	}
144 
145 	return 0;
146 }
147 
148 static int cs_etm_validate_timestamp(struct perf_pmu *cs_etm_pmu, struct evsel *evsel,
149 				     struct perf_cpu cpu)
150 {
151 	int err;
152 	__u64 val;
153 
154 	if (!(evsel->core.attr.config &
155 	      perf_pmu__format_bits(cs_etm_pmu, "timestamp")))
156 		return 0;
157 
158 	if (cs_etm_get_version(cs_etm_pmu, cpu) == CS_ETMV3) {
159 		pr_err("%s: timestamp not supported in ETMv3, disable with %s/timestamp=0/\n",
160 		       CORESIGHT_ETM_PMU_NAME, CORESIGHT_ETM_PMU_NAME);
161 		return -EINVAL;
162 	}
163 
164 	/* Get a handle on TRCIRD0 */
165 	err = cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR0], &val);
166 	if (err)
167 		return err;
168 
169 	/*
170 	 * TRCIDR0.TSSIZE, bit [28-24], indicates whether global timestamping
171 	 * is supported:
172 	 *  0b00000 Global timestamping is not implemented
173 	 *  0b00110 Implementation supports a maximum timestamp of 48bits.
174 	 *  0b01000 Implementation supports a maximum timestamp of 64bits.
175 	 */
176 	val &= GENMASK(28, 24);
177 	if (!val) {
178 		return -EINVAL;
179 	}
180 
181 	return 0;
182 }
183 
184 static struct perf_pmu *cs_etm_get_pmu(struct auxtrace_record *itr)
185 {
186 	struct cs_etm_recording *ptr = container_of(itr, struct cs_etm_recording, itr);
187 
188 	return ptr->cs_etm_pmu;
189 }
190 
191 /*
192  * Check whether the requested timestamp and contextid options should be
193  * available on all requested CPUs and if not, tell the user how to override.
194  * The kernel will silently disable any unavailable options so a warning here
195  * first is better. In theory the kernel could still disable the option for
196  * some other reason so this is best effort only.
197  */
198 static int cs_etm_validate_config(struct perf_pmu *cs_etm_pmu,
199 				  struct evsel *evsel)
200 {
201 	int idx, err = 0;
202 	struct perf_cpu_map *event_cpus = evsel->evlist->core.user_requested_cpus;
203 	struct perf_cpu_map *intersect_cpus;
204 	struct perf_cpu cpu;
205 
206 	/*
207 	 * Set option of each CPU we have. In per-cpu case, do the validation
208 	 * for CPUs to work with. In per-thread case, the CPU map has the "any"
209 	 * CPU value. Since the traced program can run on any CPUs in this case,
210 	 * thus don't skip validation.
211 	 */
212 	if (!perf_cpu_map__has_any_cpu(event_cpus)) {
213 		struct perf_cpu_map *online_cpus = perf_cpu_map__new_online_cpus();
214 
215 		intersect_cpus = perf_cpu_map__intersect(event_cpus, online_cpus);
216 		perf_cpu_map__put(online_cpus);
217 	} else {
218 		intersect_cpus = perf_cpu_map__new_online_cpus();
219 	}
220 
221 	perf_cpu_map__for_each_cpu_skip_any(cpu, idx, intersect_cpus) {
222 		if (cs_etm_get_version(cs_etm_pmu, cpu) == CS_NOT_PRESENT) {
223 			pr_err("%s: Not found on CPU %d. Check hardware and firmware support and that all Coresight drivers are loaded\n",
224 			       CORESIGHT_ETM_PMU_NAME, cpu.cpu);
225 			return -EINVAL;
226 		}
227 		err = cs_etm_validate_context_id(cs_etm_pmu, evsel, cpu);
228 		if (err)
229 			break;
230 
231 		err = cs_etm_validate_timestamp(cs_etm_pmu, evsel, cpu);
232 		if (err)
233 			break;
234 	}
235 
236 	perf_cpu_map__put(intersect_cpus);
237 	return err;
238 }
239 
240 static int cs_etm_parse_snapshot_options(struct auxtrace_record *itr,
241 					 struct record_opts *opts,
242 					 const char *str)
243 {
244 	struct cs_etm_recording *ptr =
245 				container_of(itr, struct cs_etm_recording, itr);
246 	unsigned long long snapshot_size = 0;
247 	char *endptr;
248 
249 	if (str) {
250 		snapshot_size = strtoull(str, &endptr, 0);
251 		if (*endptr || snapshot_size > SIZE_MAX)
252 			return -1;
253 	}
254 
255 	opts->auxtrace_snapshot_mode = true;
256 	opts->auxtrace_snapshot_size = snapshot_size;
257 	ptr->snapshot_size = snapshot_size;
258 
259 	return 0;
260 }
261 
262 static int cs_etm_set_sink_attr(struct perf_pmu *pmu,
263 				struct evsel *evsel)
264 {
265 	char msg[BUFSIZ], path[PATH_MAX], *sink;
266 	struct evsel_config_term *term;
267 	int ret = -EINVAL;
268 	u32 hash;
269 
270 	if (evsel->core.attr.config2 & GENMASK(31, 0))
271 		return 0;
272 
273 	list_for_each_entry(term, &evsel->config_terms, list) {
274 		if (term->type != EVSEL__CONFIG_TERM_DRV_CFG)
275 			continue;
276 
277 		sink = term->val.str;
278 		snprintf(path, PATH_MAX, "sinks/%s", sink);
279 
280 		ret = perf_pmu__scan_file(pmu, path, "%x", &hash);
281 		if (ret != 1) {
282 			if (errno == ENOENT)
283 				pr_err("Couldn't find sink \"%s\" on event %s\n"
284 				       "Missing kernel or device support?\n\n"
285 				       "Hint: An appropriate sink will be picked automatically if one isn't specified.\n",
286 				       sink, evsel__name(evsel));
287 			else
288 				pr_err("Failed to set sink \"%s\" on event %s with %d (%s)\n",
289 				       sink, evsel__name(evsel), errno,
290 				       str_error_r(errno, msg, sizeof(msg)));
291 			return ret;
292 		}
293 
294 		evsel->core.attr.config2 |= hash;
295 		return 0;
296 	}
297 
298 	/*
299 	 * No sink was provided on the command line - allow the CoreSight
300 	 * system to look for a default
301 	 */
302 	return 0;
303 }
304 
305 static int cs_etm_recording_options(struct auxtrace_record *itr,
306 				    struct evlist *evlist,
307 				    struct record_opts *opts)
308 {
309 	int ret;
310 	struct cs_etm_recording *ptr =
311 				container_of(itr, struct cs_etm_recording, itr);
312 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
313 	struct evsel *evsel, *cs_etm_evsel = NULL;
314 	struct perf_cpu_map *cpus = evlist->core.user_requested_cpus;
315 	bool privileged = perf_event_paranoid_check(-1);
316 	int err = 0;
317 
318 	evlist__for_each_entry(evlist, evsel) {
319 		if (evsel->core.attr.type == cs_etm_pmu->type) {
320 			if (cs_etm_evsel) {
321 				pr_err("There may be only one %s event\n",
322 				       CORESIGHT_ETM_PMU_NAME);
323 				return -EINVAL;
324 			}
325 			cs_etm_evsel = evsel;
326 		}
327 	}
328 
329 	/* no need to continue if at least one event of interest was found */
330 	if (!cs_etm_evsel)
331 		return 0;
332 
333 	ptr->evlist = evlist;
334 	ptr->snapshot_mode = opts->auxtrace_snapshot_mode;
335 
336 	if (!record_opts__no_switch_events(opts) &&
337 	    perf_can_record_switch_events())
338 		opts->record_switch_events = true;
339 
340 	cs_etm_evsel->needs_auxtrace_mmap = true;
341 	opts->full_auxtrace = true;
342 
343 	ret = cs_etm_set_sink_attr(cs_etm_pmu, cs_etm_evsel);
344 	if (ret)
345 		return ret;
346 
347 	if (opts->use_clockid) {
348 		pr_err("Cannot use clockid (-k option) with %s\n",
349 		       CORESIGHT_ETM_PMU_NAME);
350 		return -EINVAL;
351 	}
352 
353 	/* we are in snapshot mode */
354 	if (opts->auxtrace_snapshot_mode) {
355 		/*
356 		 * No size were given to '-S' or '-m,', so go with
357 		 * the default
358 		 */
359 		if (!opts->auxtrace_snapshot_size &&
360 		    !opts->auxtrace_mmap_pages) {
361 			if (privileged) {
362 				opts->auxtrace_mmap_pages = MiB(4) / page_size;
363 			} else {
364 				opts->auxtrace_mmap_pages =
365 							KiB(128) / page_size;
366 				if (opts->mmap_pages == UINT_MAX)
367 					opts->mmap_pages = KiB(256) / page_size;
368 			}
369 		} else if (!opts->auxtrace_mmap_pages && !privileged &&
370 						opts->mmap_pages == UINT_MAX) {
371 			opts->mmap_pages = KiB(256) / page_size;
372 		}
373 
374 		/*
375 		 * '-m,xyz' was specified but no snapshot size, so make the
376 		 * snapshot size as big as the auxtrace mmap area.
377 		 */
378 		if (!opts->auxtrace_snapshot_size) {
379 			opts->auxtrace_snapshot_size =
380 				opts->auxtrace_mmap_pages * (size_t)page_size;
381 		}
382 
383 		/*
384 		 * -Sxyz was specified but no auxtrace mmap area, so make the
385 		 * auxtrace mmap area big enough to fit the requested snapshot
386 		 * size.
387 		 */
388 		if (!opts->auxtrace_mmap_pages) {
389 			size_t sz = opts->auxtrace_snapshot_size;
390 
391 			sz = round_up(sz, page_size) / page_size;
392 			opts->auxtrace_mmap_pages = roundup_pow_of_two(sz);
393 		}
394 
395 		/* Snapshot size can't be bigger than the auxtrace area */
396 		if (opts->auxtrace_snapshot_size >
397 				opts->auxtrace_mmap_pages * (size_t)page_size) {
398 			pr_err("Snapshot size %zu must not be greater than AUX area tracing mmap size %zu\n",
399 			       opts->auxtrace_snapshot_size,
400 			       opts->auxtrace_mmap_pages * (size_t)page_size);
401 			return -EINVAL;
402 		}
403 
404 		/* Something went wrong somewhere - this shouldn't happen */
405 		if (!opts->auxtrace_snapshot_size ||
406 		    !opts->auxtrace_mmap_pages) {
407 			pr_err("Failed to calculate default snapshot size and/or AUX area tracing mmap pages\n");
408 			return -EINVAL;
409 		}
410 	}
411 
412 	/* Buffer sizes weren't specified with '-m,xyz' so give some defaults */
413 	if (!opts->auxtrace_mmap_pages) {
414 		if (privileged) {
415 			opts->auxtrace_mmap_pages = MiB(4) / page_size;
416 		} else {
417 			opts->auxtrace_mmap_pages = KiB(128) / page_size;
418 			if (opts->mmap_pages == UINT_MAX)
419 				opts->mmap_pages = KiB(256) / page_size;
420 		}
421 	}
422 
423 	if (opts->auxtrace_snapshot_mode)
424 		pr_debug2("%s snapshot size: %zu\n", CORESIGHT_ETM_PMU_NAME,
425 			  opts->auxtrace_snapshot_size);
426 
427 	/*
428 	 * To obtain the auxtrace buffer file descriptor, the auxtrace
429 	 * event must come first.
430 	 */
431 	evlist__to_front(evlist, cs_etm_evsel);
432 
433 	/*
434 	 * get the CPU on the sample - need it to associate trace ID in the
435 	 * AUX_OUTPUT_HW_ID event, and the AUX event for per-cpu mmaps.
436 	 */
437 	evsel__set_sample_bit(cs_etm_evsel, CPU);
438 
439 	/*
440 	 * Also the case of per-cpu mmaps, need the contextID in order to be notified
441 	 * when a context switch happened.
442 	 */
443 	if (!perf_cpu_map__is_any_cpu_or_is_empty(cpus)) {
444 		evsel__set_config_if_unset(cs_etm_pmu, cs_etm_evsel,
445 					   "timestamp", 1);
446 		evsel__set_config_if_unset(cs_etm_pmu, cs_etm_evsel,
447 					   "contextid", 1);
448 	}
449 
450 	/*
451 	 * When the option '--timestamp' or '-T' is enabled, the PERF_SAMPLE_TIME
452 	 * bit is set for all events.  In this case, always enable Arm CoreSight
453 	 * timestamp tracing.
454 	 */
455 	if (opts->sample_time_set)
456 		evsel__set_config_if_unset(cs_etm_pmu, cs_etm_evsel,
457 					   "timestamp", 1);
458 
459 	/* Add dummy event to keep tracking */
460 	err = parse_event(evlist, "dummy:u");
461 	if (err)
462 		goto out;
463 	evsel = evlist__last(evlist);
464 	evlist__set_tracking_event(evlist, evsel);
465 	evsel->core.attr.freq = 0;
466 	evsel->core.attr.sample_period = 1;
467 
468 	/* In per-cpu case, always need the time of mmap events etc */
469 	if (!perf_cpu_map__is_any_cpu_or_is_empty(cpus))
470 		evsel__set_sample_bit(evsel, TIME);
471 
472 	err = cs_etm_validate_config(cs_etm_pmu, cs_etm_evsel);
473 out:
474 	return err;
475 }
476 
477 static u64 cs_etm_get_config(struct auxtrace_record *itr)
478 {
479 	u64 config = 0;
480 	struct cs_etm_recording *ptr =
481 			container_of(itr, struct cs_etm_recording, itr);
482 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
483 	struct evlist *evlist = ptr->evlist;
484 	struct evsel *evsel;
485 
486 	evlist__for_each_entry(evlist, evsel) {
487 		if (evsel->core.attr.type == cs_etm_pmu->type) {
488 			/*
489 			 * Variable perf_event_attr::config is assigned to
490 			 * ETMv3/PTM.  The bit fields have been made to match
491 			 * the ETMv3.5 ETRMCR register specification.  See the
492 			 * PMU_FORMAT_ATTR() declarations in
493 			 * drivers/hwtracing/coresight/coresight-perf.c for
494 			 * details.
495 			 */
496 			config = evsel->core.attr.config;
497 			break;
498 		}
499 	}
500 
501 	return config;
502 }
503 
504 #ifndef BIT
505 #define BIT(N) (1UL << (N))
506 #endif
507 
508 static u64 cs_etmv4_get_config(struct auxtrace_record *itr)
509 {
510 	u64 config = 0;
511 	u64 config_opts = 0;
512 
513 	/*
514 	 * The perf event variable config bits represent both
515 	 * the command line options and register programming
516 	 * bits in ETMv3/PTM. For ETMv4 we must remap options
517 	 * to real bits
518 	 */
519 	config_opts = cs_etm_get_config(itr);
520 	if (config_opts & BIT(ETM_OPT_CYCACC))
521 		config |= BIT(ETM4_CFG_BIT_CYCACC);
522 	if (config_opts & BIT(ETM_OPT_CTXTID))
523 		config |= BIT(ETM4_CFG_BIT_CTXTID);
524 	if (config_opts & BIT(ETM_OPT_TS))
525 		config |= BIT(ETM4_CFG_BIT_TS);
526 	if (config_opts & BIT(ETM_OPT_RETSTK))
527 		config |= BIT(ETM4_CFG_BIT_RETSTK);
528 	if (config_opts & BIT(ETM_OPT_CTXTID2))
529 		config |= BIT(ETM4_CFG_BIT_VMID) |
530 			  BIT(ETM4_CFG_BIT_VMID_OPT);
531 	if (config_opts & BIT(ETM_OPT_BRANCH_BROADCAST))
532 		config |= BIT(ETM4_CFG_BIT_BB);
533 
534 	return config;
535 }
536 
537 static size_t
538 cs_etm_info_priv_size(struct auxtrace_record *itr,
539 		      struct evlist *evlist)
540 {
541 	int idx;
542 	int etmv3 = 0, etmv4 = 0, ete = 0;
543 	struct perf_cpu_map *event_cpus = evlist->core.user_requested_cpus;
544 	struct perf_cpu_map *intersect_cpus;
545 	struct perf_cpu cpu;
546 	struct perf_pmu *cs_etm_pmu = cs_etm_get_pmu(itr);
547 
548 	if (!perf_cpu_map__has_any_cpu(event_cpus)) {
549 		/* cpu map is not "any" CPU , we have specific CPUs to work with */
550 		struct perf_cpu_map *online_cpus = perf_cpu_map__new_online_cpus();
551 
552 		intersect_cpus = perf_cpu_map__intersect(event_cpus, online_cpus);
553 		perf_cpu_map__put(online_cpus);
554 	} else {
555 		/* Event can be "any" CPU so count all online CPUs. */
556 		intersect_cpus = perf_cpu_map__new_online_cpus();
557 	}
558 	/* Count number of each type of ETM. Don't count if that CPU has CS_NOT_PRESENT. */
559 	perf_cpu_map__for_each_cpu_skip_any(cpu, idx, intersect_cpus) {
560 		enum cs_etm_version v = cs_etm_get_version(cs_etm_pmu, cpu);
561 
562 		ete   += v == CS_ETE;
563 		etmv4 += v == CS_ETMV4;
564 		etmv3 += v == CS_ETMV3;
565 	}
566 	perf_cpu_map__put(intersect_cpus);
567 
568 	return (CS_ETM_HEADER_SIZE +
569 	       (ete   * CS_ETE_PRIV_SIZE) +
570 	       (etmv4 * CS_ETMV4_PRIV_SIZE) +
571 	       (etmv3 * CS_ETMV3_PRIV_SIZE));
572 }
573 
574 static int cs_etm_get_ro(struct perf_pmu *pmu, struct perf_cpu cpu, const char *path, __u64 *val)
575 {
576 	char pmu_path[PATH_MAX];
577 	int scan;
578 
579 	/* Get RO metadata from sysfs */
580 	snprintf(pmu_path, PATH_MAX, "cpu%d/%s", cpu.cpu, path);
581 
582 	scan = perf_pmu__scan_file(pmu, pmu_path, "%llx", val);
583 	if (scan != 1) {
584 		pr_err("%s: error reading: %s\n", __func__, pmu_path);
585 		return -EINVAL;
586 	}
587 
588 	return 0;
589 }
590 
591 static int cs_etm_get_ro_signed(struct perf_pmu *pmu, struct perf_cpu cpu, const char *path,
592 				__u64 *out_val)
593 {
594 	char pmu_path[PATH_MAX];
595 	int scan;
596 	int val = 0;
597 
598 	/* Get RO metadata from sysfs */
599 	snprintf(pmu_path, PATH_MAX, "cpu%d/%s", cpu.cpu, path);
600 
601 	scan = perf_pmu__scan_file(pmu, pmu_path, "%d", &val);
602 	if (scan != 1) {
603 		pr_err("%s: error reading: %s\n", __func__, pmu_path);
604 		return -EINVAL;
605 	}
606 
607 	*out_val = (__u64) val;
608 	return 0;
609 }
610 
611 static bool cs_etm_pmu_path_exists(struct perf_pmu *pmu, struct perf_cpu cpu, const char *path)
612 {
613 	char pmu_path[PATH_MAX];
614 
615 	/* Get RO metadata from sysfs */
616 	snprintf(pmu_path, PATH_MAX, "cpu%d/%s", cpu.cpu, path);
617 
618 	return perf_pmu__file_exists(pmu, pmu_path);
619 }
620 
621 #define TRCDEVARCH_ARCHPART_SHIFT 0
622 #define TRCDEVARCH_ARCHPART_MASK  GENMASK(11, 0)
623 #define TRCDEVARCH_ARCHPART(x)    (((x) & TRCDEVARCH_ARCHPART_MASK) >> TRCDEVARCH_ARCHPART_SHIFT)
624 
625 #define TRCDEVARCH_ARCHVER_SHIFT 12
626 #define TRCDEVARCH_ARCHVER_MASK  GENMASK(15, 12)
627 #define TRCDEVARCH_ARCHVER(x)    (((x) & TRCDEVARCH_ARCHVER_MASK) >> TRCDEVARCH_ARCHVER_SHIFT)
628 
629 static bool cs_etm_is_ete(struct perf_pmu *cs_etm_pmu, struct perf_cpu cpu)
630 {
631 	__u64 trcdevarch;
632 
633 	if (!cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCDEVARCH]))
634 		return false;
635 
636 	cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCDEVARCH], &trcdevarch);
637 	/*
638 	 * ETE if ARCHVER is 5 (ARCHVER is 4 for ETM) and ARCHPART is 0xA13.
639 	 * See ETM_DEVARCH_ETE_ARCH in coresight-etm4x.h
640 	 */
641 	return TRCDEVARCH_ARCHVER(trcdevarch) == 5 && TRCDEVARCH_ARCHPART(trcdevarch) == 0xA13;
642 }
643 
644 static __u64 cs_etm_get_legacy_trace_id(struct perf_cpu cpu)
645 {
646 	return CORESIGHT_LEGACY_CPU_TRACE_ID(cpu.cpu);
647 }
648 
649 static void cs_etm_save_etmv4_header(__u64 data[], struct auxtrace_record *itr, struct perf_cpu cpu)
650 {
651 	struct cs_etm_recording *ptr = container_of(itr, struct cs_etm_recording, itr);
652 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
653 
654 	/* Get trace configuration register */
655 	data[CS_ETMV4_TRCCONFIGR] = cs_etmv4_get_config(itr);
656 	/* traceID set to legacy version, in case new perf running on older system */
657 	data[CS_ETMV4_TRCTRACEIDR] = cs_etm_get_legacy_trace_id(cpu) |
658 				     CORESIGHT_TRACE_ID_UNUSED_FLAG;
659 
660 	/* Get read-only information from sysFS */
661 	cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR0],
662 		      &data[CS_ETMV4_TRCIDR0]);
663 	cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR1],
664 		      &data[CS_ETMV4_TRCIDR1]);
665 	cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR2],
666 		      &data[CS_ETMV4_TRCIDR2]);
667 	cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR8],
668 		      &data[CS_ETMV4_TRCIDR8]);
669 	cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TRCAUTHSTATUS],
670 		      &data[CS_ETMV4_TRCAUTHSTATUS]);
671 
672 	/* Kernels older than 5.19 may not expose ts_source */
673 	if (!cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TS_SOURCE]) ||
674 	    cs_etm_get_ro_signed(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TS_SOURCE],
675 				 &data[CS_ETMV4_TS_SOURCE])) {
676 		pr_debug3("[%03d] pmu file 'ts_source' not found. Fallback to safe value (-1)\n",
677 			  cpu.cpu);
678 		data[CS_ETMV4_TS_SOURCE] = (__u64) -1;
679 	}
680 }
681 
682 static void cs_etm_save_ete_header(__u64 data[], struct auxtrace_record *itr, struct perf_cpu cpu)
683 {
684 	struct cs_etm_recording *ptr = container_of(itr, struct cs_etm_recording, itr);
685 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
686 
687 	/* Get trace configuration register */
688 	data[CS_ETE_TRCCONFIGR] = cs_etmv4_get_config(itr);
689 	/* traceID set to legacy version, in case new perf running on older system */
690 	data[CS_ETE_TRCTRACEIDR] = cs_etm_get_legacy_trace_id(cpu) | CORESIGHT_TRACE_ID_UNUSED_FLAG;
691 
692 	/* Get read-only information from sysFS */
693 	cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCIDR0], &data[CS_ETE_TRCIDR0]);
694 	cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCIDR1], &data[CS_ETE_TRCIDR1]);
695 	cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCIDR2], &data[CS_ETE_TRCIDR2]);
696 	cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCIDR8], &data[CS_ETE_TRCIDR8]);
697 	cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCAUTHSTATUS],
698 		      &data[CS_ETE_TRCAUTHSTATUS]);
699 	/* ETE uses the same registers as ETMv4 plus TRCDEVARCH */
700 	cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCDEVARCH],
701 		      &data[CS_ETE_TRCDEVARCH]);
702 
703 	/* Kernels older than 5.19 may not expose ts_source */
704 	if (!cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TS_SOURCE]) ||
705 	    cs_etm_get_ro_signed(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TS_SOURCE],
706 				 &data[CS_ETE_TS_SOURCE])) {
707 		pr_debug3("[%03d] pmu file 'ts_source' not found. Fallback to safe value (-1)\n",
708 			  cpu.cpu);
709 		data[CS_ETE_TS_SOURCE] = (__u64) -1;
710 	}
711 }
712 
713 static void cs_etm_get_metadata(struct perf_cpu cpu, u32 *offset,
714 				struct auxtrace_record *itr,
715 				struct perf_record_auxtrace_info *info)
716 {
717 	u32 increment, nr_trc_params;
718 	u64 magic;
719 	struct perf_pmu *cs_etm_pmu = cs_etm_get_pmu(itr);
720 
721 	/* first see what kind of tracer this cpu is affined to */
722 	switch (cs_etm_get_version(cs_etm_pmu, cpu)) {
723 	case CS_ETE:
724 		magic = __perf_cs_ete_magic;
725 		cs_etm_save_ete_header(&info->priv[*offset], itr, cpu);
726 
727 		/* How much space was used */
728 		increment = CS_ETE_PRIV_MAX;
729 		nr_trc_params = CS_ETE_PRIV_MAX - CS_ETM_COMMON_BLK_MAX_V1;
730 		break;
731 
732 	case CS_ETMV4:
733 		magic = __perf_cs_etmv4_magic;
734 		cs_etm_save_etmv4_header(&info->priv[*offset], itr, cpu);
735 
736 		/* How much space was used */
737 		increment = CS_ETMV4_PRIV_MAX;
738 		nr_trc_params = CS_ETMV4_PRIV_MAX - CS_ETMV4_TRCCONFIGR;
739 		break;
740 
741 	case CS_ETMV3:
742 		magic = __perf_cs_etmv3_magic;
743 		/* Get configuration register */
744 		info->priv[*offset + CS_ETM_ETMCR] = cs_etm_get_config(itr);
745 		/* traceID set to legacy value in case new perf running on old system */
746 		info->priv[*offset + CS_ETM_ETMTRACEIDR] = cs_etm_get_legacy_trace_id(cpu) |
747 							   CORESIGHT_TRACE_ID_UNUSED_FLAG;
748 		/* Get read-only information from sysFS */
749 		cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv3_ro[CS_ETM_ETMCCER],
750 			      &info->priv[*offset + CS_ETM_ETMCCER]);
751 		cs_etm_get_ro(cs_etm_pmu, cpu, metadata_etmv3_ro[CS_ETM_ETMIDR],
752 			      &info->priv[*offset + CS_ETM_ETMIDR]);
753 
754 		/* How much space was used */
755 		increment = CS_ETM_PRIV_MAX;
756 		nr_trc_params = CS_ETM_PRIV_MAX - CS_ETM_ETMCR;
757 		break;
758 
759 	default:
760 	case CS_NOT_PRESENT:
761 		/* Unreachable, CPUs already validated in cs_etm_validate_config() */
762 		assert(true);
763 		return;
764 	}
765 
766 	/* Build generic header portion */
767 	info->priv[*offset + CS_ETM_MAGIC] = magic;
768 	info->priv[*offset + CS_ETM_CPU] = cpu.cpu;
769 	info->priv[*offset + CS_ETM_NR_TRC_PARAMS] = nr_trc_params;
770 	/* Where the next CPU entry should start from */
771 	*offset += increment;
772 }
773 
774 static int cs_etm_info_fill(struct auxtrace_record *itr,
775 			    struct perf_session *session,
776 			    struct perf_record_auxtrace_info *info,
777 			    size_t priv_size)
778 {
779 	int i;
780 	u32 offset;
781 	u64 nr_cpu, type;
782 	struct perf_cpu_map *cpu_map;
783 	struct perf_cpu_map *event_cpus = session->evlist->core.user_requested_cpus;
784 	struct perf_cpu_map *online_cpus = perf_cpu_map__new_online_cpus();
785 	struct cs_etm_recording *ptr =
786 			container_of(itr, struct cs_etm_recording, itr);
787 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
788 	struct perf_cpu cpu;
789 
790 	if (priv_size != cs_etm_info_priv_size(itr, session->evlist))
791 		return -EINVAL;
792 
793 	if (!session->evlist->core.nr_mmaps)
794 		return -EINVAL;
795 
796 	/* If the cpu_map has the "any" CPU all online CPUs are involved */
797 	if (perf_cpu_map__has_any_cpu(event_cpus)) {
798 		cpu_map = online_cpus;
799 	} else {
800 		/* Make sure all specified CPUs are online */
801 		perf_cpu_map__for_each_cpu(cpu, i, event_cpus) {
802 			if (!perf_cpu_map__has(online_cpus, cpu))
803 				return -EINVAL;
804 		}
805 
806 		cpu_map = event_cpus;
807 	}
808 
809 	nr_cpu = perf_cpu_map__nr(cpu_map);
810 	/* Get PMU type as dynamically assigned by the core */
811 	type = cs_etm_pmu->type;
812 
813 	/* First fill out the session header */
814 	info->type = PERF_AUXTRACE_CS_ETM;
815 	info->priv[CS_HEADER_VERSION] = CS_HEADER_CURRENT_VERSION;
816 	info->priv[CS_PMU_TYPE_CPUS] = type << 32;
817 	info->priv[CS_PMU_TYPE_CPUS] |= nr_cpu;
818 	info->priv[CS_ETM_SNAPSHOT] = ptr->snapshot_mode;
819 
820 	offset = CS_ETM_SNAPSHOT + 1;
821 
822 	perf_cpu_map__for_each_cpu(cpu, i, cpu_map) {
823 		assert(offset < priv_size);
824 		cs_etm_get_metadata(cpu, &offset, itr, info);
825 	}
826 
827 	perf_cpu_map__put(online_cpus);
828 
829 	return 0;
830 }
831 
832 static int cs_etm_snapshot_start(struct auxtrace_record *itr)
833 {
834 	struct cs_etm_recording *ptr =
835 			container_of(itr, struct cs_etm_recording, itr);
836 	struct evsel *evsel;
837 
838 	evlist__for_each_entry(ptr->evlist, evsel) {
839 		if (evsel->core.attr.type == ptr->cs_etm_pmu->type)
840 			return evsel__disable(evsel);
841 	}
842 	return -EINVAL;
843 }
844 
845 static int cs_etm_snapshot_finish(struct auxtrace_record *itr)
846 {
847 	struct cs_etm_recording *ptr =
848 			container_of(itr, struct cs_etm_recording, itr);
849 	struct evsel *evsel;
850 
851 	evlist__for_each_entry(ptr->evlist, evsel) {
852 		if (evsel->core.attr.type == ptr->cs_etm_pmu->type)
853 			return evsel__enable(evsel);
854 	}
855 	return -EINVAL;
856 }
857 
858 static u64 cs_etm_reference(struct auxtrace_record *itr __maybe_unused)
859 {
860 	return (((u64) rand() <<  0) & 0x00000000FFFFFFFFull) |
861 		(((u64) rand() << 32) & 0xFFFFFFFF00000000ull);
862 }
863 
864 static void cs_etm_recording_free(struct auxtrace_record *itr)
865 {
866 	struct cs_etm_recording *ptr =
867 			container_of(itr, struct cs_etm_recording, itr);
868 
869 	free(ptr);
870 }
871 
872 struct auxtrace_record *cs_etm_record_init(int *err)
873 {
874 	struct perf_pmu *cs_etm_pmu;
875 	struct cs_etm_recording *ptr;
876 
877 	cs_etm_pmu = perf_pmus__find(CORESIGHT_ETM_PMU_NAME);
878 
879 	if (!cs_etm_pmu) {
880 		*err = -EINVAL;
881 		goto out;
882 	}
883 
884 	ptr = zalloc(sizeof(struct cs_etm_recording));
885 	if (!ptr) {
886 		*err = -ENOMEM;
887 		goto out;
888 	}
889 
890 	ptr->cs_etm_pmu			= cs_etm_pmu;
891 	ptr->itr.pmu			= cs_etm_pmu;
892 	ptr->itr.parse_snapshot_options	= cs_etm_parse_snapshot_options;
893 	ptr->itr.recording_options	= cs_etm_recording_options;
894 	ptr->itr.info_priv_size		= cs_etm_info_priv_size;
895 	ptr->itr.info_fill		= cs_etm_info_fill;
896 	ptr->itr.snapshot_start		= cs_etm_snapshot_start;
897 	ptr->itr.snapshot_finish	= cs_etm_snapshot_finish;
898 	ptr->itr.reference		= cs_etm_reference;
899 	ptr->itr.free			= cs_etm_recording_free;
900 	ptr->itr.read_finish		= auxtrace_record__read_finish;
901 
902 	*err = 0;
903 	return &ptr->itr;
904 out:
905 	return NULL;
906 }
907 
908 /*
909  * Set a default config to enable the user changed config tracking mechanism
910  * (CFG_CHG and evsel__set_config_if_unset()). If no default is set then user
911  * changes aren't tracked.
912  */
913 void
914 cs_etm_get_default_config(const struct perf_pmu *pmu __maybe_unused,
915 			  struct perf_event_attr *attr)
916 {
917 	attr->sample_period = 1;
918 }
919