xref: /linux/tools/perf/arch/arm/util/cs-etm.c (revision 2672031b20f6681514bef14ddcfe8c62c2757d11)
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 static bool cs_etm_is_etmv4(struct auxtrace_record *itr, int cpu);
70 static bool cs_etm_is_ete(struct auxtrace_record *itr, int cpu);
71 
72 static int cs_etm_validate_context_id(struct auxtrace_record *itr,
73 				      struct evsel *evsel, int cpu)
74 {
75 	struct cs_etm_recording *ptr =
76 		container_of(itr, struct cs_etm_recording, itr);
77 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
78 	char path[PATH_MAX];
79 	int err;
80 	u32 val;
81 	u64 contextid = evsel->core.attr.config &
82 		(perf_pmu__format_bits(cs_etm_pmu, "contextid") |
83 		 perf_pmu__format_bits(cs_etm_pmu, "contextid1") |
84 		 perf_pmu__format_bits(cs_etm_pmu, "contextid2"));
85 
86 	if (!contextid)
87 		return 0;
88 
89 	/* Not supported in etmv3 */
90 	if (!cs_etm_is_etmv4(itr, cpu)) {
91 		pr_err("%s: contextid not supported in ETMv3, disable with %s/contextid=0/\n",
92 		       CORESIGHT_ETM_PMU_NAME, CORESIGHT_ETM_PMU_NAME);
93 		return -EINVAL;
94 	}
95 
96 	/* Get a handle on TRCIDR2 */
97 	snprintf(path, PATH_MAX, "cpu%d/%s",
98 		 cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR2]);
99 	err = perf_pmu__scan_file(cs_etm_pmu, path, "%x", &val);
100 
101 	/* There was a problem reading the file, bailing out */
102 	if (err != 1) {
103 		pr_err("%s: can't read file %s\n", CORESIGHT_ETM_PMU_NAME,
104 		       path);
105 		return err;
106 	}
107 
108 	if (contextid &
109 	    perf_pmu__format_bits(cs_etm_pmu, "contextid1")) {
110 		/*
111 		 * TRCIDR2.CIDSIZE, bit [9-5], indicates whether contextID
112 		 * tracing is supported:
113 		 *  0b00000 Context ID tracing is not supported.
114 		 *  0b00100 Maximum of 32-bit Context ID size.
115 		 *  All other values are reserved.
116 		 */
117 		if (BMVAL(val, 5, 9) != 0x4) {
118 			pr_err("%s: CONTEXTIDR_EL1 isn't supported, disable with %s/contextid1=0/\n",
119 			       CORESIGHT_ETM_PMU_NAME, CORESIGHT_ETM_PMU_NAME);
120 			return -EINVAL;
121 		}
122 	}
123 
124 	if (contextid &
125 	    perf_pmu__format_bits(cs_etm_pmu, "contextid2")) {
126 		/*
127 		 * TRCIDR2.VMIDOPT[30:29] != 0 and
128 		 * TRCIDR2.VMIDSIZE[14:10] == 0b00100 (32bit virtual contextid)
129 		 * We can't support CONTEXTIDR in VMID if the size of the
130 		 * virtual context id is < 32bit.
131 		 * Any value of VMIDSIZE >= 4 (i.e, > 32bit) is fine for us.
132 		 */
133 		if (!BMVAL(val, 29, 30) || BMVAL(val, 10, 14) < 4) {
134 			pr_err("%s: CONTEXTIDR_EL2 isn't supported, disable with %s/contextid2=0/\n",
135 			       CORESIGHT_ETM_PMU_NAME, CORESIGHT_ETM_PMU_NAME);
136 			return -EINVAL;
137 		}
138 	}
139 
140 	return 0;
141 }
142 
143 static int cs_etm_validate_timestamp(struct auxtrace_record *itr,
144 				     struct evsel *evsel, int cpu)
145 {
146 	struct cs_etm_recording *ptr =
147 		container_of(itr, struct cs_etm_recording, itr);
148 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
149 	char path[PATH_MAX];
150 	int err;
151 	u32 val;
152 
153 	if (!(evsel->core.attr.config &
154 	      perf_pmu__format_bits(cs_etm_pmu, "timestamp")))
155 		return 0;
156 
157 	if (!cs_etm_is_etmv4(itr, cpu)) {
158 		pr_err("%s: timestamp not supported in ETMv3, disable with %s/timestamp=0/\n",
159 		       CORESIGHT_ETM_PMU_NAME, CORESIGHT_ETM_PMU_NAME);
160 		return -EINVAL;
161 	}
162 
163 	/* Get a handle on TRCIRD0 */
164 	snprintf(path, PATH_MAX, "cpu%d/%s",
165 		 cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR0]);
166 	err = perf_pmu__scan_file(cs_etm_pmu, path, "%x", &val);
167 
168 	/* There was a problem reading the file, bailing out */
169 	if (err != 1) {
170 		pr_err("%s: can't read file %s\n",
171 		       CORESIGHT_ETM_PMU_NAME, path);
172 		return err;
173 	}
174 
175 	/*
176 	 * TRCIDR0.TSSIZE, bit [28-24], indicates whether global timestamping
177 	 * is supported:
178 	 *  0b00000 Global timestamping is not implemented
179 	 *  0b00110 Implementation supports a maximum timestamp of 48bits.
180 	 *  0b01000 Implementation supports a maximum timestamp of 64bits.
181 	 */
182 	val &= GENMASK(28, 24);
183 	if (!val) {
184 		return -EINVAL;
185 	}
186 
187 	return 0;
188 }
189 
190 /*
191  * Check whether the requested timestamp and contextid options should be
192  * available on all requested CPUs and if not, tell the user how to override.
193  * The kernel will silently disable any unavailable options so a warning here
194  * first is better. In theory the kernel could still disable the option for
195  * some other reason so this is best effort only.
196  */
197 static int cs_etm_validate_config(struct auxtrace_record *itr,
198 				  struct evsel *evsel)
199 {
200 	int i, err = -EINVAL;
201 	struct perf_cpu_map *event_cpus = evsel->evlist->core.user_requested_cpus;
202 	struct perf_cpu_map *online_cpus = perf_cpu_map__new_online_cpus();
203 
204 	/* Set option of each CPU we have */
205 	for (i = 0; i < cpu__max_cpu().cpu; i++) {
206 		struct perf_cpu cpu = { .cpu = i, };
207 
208 		/*
209 		 * In per-cpu case, do the validation for CPUs to work with.
210 		 * In per-thread case, the CPU map is empty.  Since the traced
211 		 * program can run on any CPUs in this case, thus don't skip
212 		 * validation.
213 		 */
214 		if (!perf_cpu_map__has_any_cpu_or_is_empty(event_cpus) &&
215 		    !perf_cpu_map__has(event_cpus, cpu))
216 			continue;
217 
218 		if (!perf_cpu_map__has(online_cpus, cpu))
219 			continue;
220 
221 		err = cs_etm_validate_context_id(itr, evsel, i);
222 		if (err)
223 			goto out;
224 		err = cs_etm_validate_timestamp(itr, evsel, i);
225 		if (err)
226 			goto out;
227 	}
228 
229 	err = 0;
230 out:
231 	perf_cpu_map__put(online_cpus);
232 	return err;
233 }
234 
235 static int cs_etm_parse_snapshot_options(struct auxtrace_record *itr,
236 					 struct record_opts *opts,
237 					 const char *str)
238 {
239 	struct cs_etm_recording *ptr =
240 				container_of(itr, struct cs_etm_recording, itr);
241 	unsigned long long snapshot_size = 0;
242 	char *endptr;
243 
244 	if (str) {
245 		snapshot_size = strtoull(str, &endptr, 0);
246 		if (*endptr || snapshot_size > SIZE_MAX)
247 			return -1;
248 	}
249 
250 	opts->auxtrace_snapshot_mode = true;
251 	opts->auxtrace_snapshot_size = snapshot_size;
252 	ptr->snapshot_size = snapshot_size;
253 
254 	return 0;
255 }
256 
257 static int cs_etm_set_sink_attr(struct perf_pmu *pmu,
258 				struct evsel *evsel)
259 {
260 	char msg[BUFSIZ], path[PATH_MAX], *sink;
261 	struct evsel_config_term *term;
262 	int ret = -EINVAL;
263 	u32 hash;
264 
265 	if (evsel->core.attr.config2 & GENMASK(31, 0))
266 		return 0;
267 
268 	list_for_each_entry(term, &evsel->config_terms, list) {
269 		if (term->type != EVSEL__CONFIG_TERM_DRV_CFG)
270 			continue;
271 
272 		sink = term->val.str;
273 		snprintf(path, PATH_MAX, "sinks/%s", sink);
274 
275 		ret = perf_pmu__scan_file(pmu, path, "%x", &hash);
276 		if (ret != 1) {
277 			if (errno == ENOENT)
278 				pr_err("Couldn't find sink \"%s\" on event %s\n"
279 				       "Missing kernel or device support?\n\n"
280 				       "Hint: An appropriate sink will be picked automatically if one isn't specified.\n",
281 				       sink, evsel__name(evsel));
282 			else
283 				pr_err("Failed to set sink \"%s\" on event %s with %d (%s)\n",
284 				       sink, evsel__name(evsel), errno,
285 				       str_error_r(errno, msg, sizeof(msg)));
286 			return ret;
287 		}
288 
289 		evsel->core.attr.config2 |= hash;
290 		return 0;
291 	}
292 
293 	/*
294 	 * No sink was provided on the command line - allow the CoreSight
295 	 * system to look for a default
296 	 */
297 	return 0;
298 }
299 
300 static int cs_etm_recording_options(struct auxtrace_record *itr,
301 				    struct evlist *evlist,
302 				    struct record_opts *opts)
303 {
304 	int ret;
305 	struct cs_etm_recording *ptr =
306 				container_of(itr, struct cs_etm_recording, itr);
307 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
308 	struct evsel *evsel, *cs_etm_evsel = NULL;
309 	struct perf_cpu_map *cpus = evlist->core.user_requested_cpus;
310 	bool privileged = perf_event_paranoid_check(-1);
311 	int err = 0;
312 
313 	evlist__for_each_entry(evlist, evsel) {
314 		if (evsel->core.attr.type == cs_etm_pmu->type) {
315 			if (cs_etm_evsel) {
316 				pr_err("There may be only one %s event\n",
317 				       CORESIGHT_ETM_PMU_NAME);
318 				return -EINVAL;
319 			}
320 			cs_etm_evsel = evsel;
321 		}
322 	}
323 
324 	/* no need to continue if at least one event of interest was found */
325 	if (!cs_etm_evsel)
326 		return 0;
327 
328 	ptr->evlist = evlist;
329 	ptr->snapshot_mode = opts->auxtrace_snapshot_mode;
330 
331 	if (!record_opts__no_switch_events(opts) &&
332 	    perf_can_record_switch_events())
333 		opts->record_switch_events = true;
334 
335 	cs_etm_evsel->needs_auxtrace_mmap = true;
336 	opts->full_auxtrace = true;
337 
338 	ret = cs_etm_set_sink_attr(cs_etm_pmu, cs_etm_evsel);
339 	if (ret)
340 		return ret;
341 
342 	if (opts->use_clockid) {
343 		pr_err("Cannot use clockid (-k option) with %s\n",
344 		       CORESIGHT_ETM_PMU_NAME);
345 		return -EINVAL;
346 	}
347 
348 	/* we are in snapshot mode */
349 	if (opts->auxtrace_snapshot_mode) {
350 		/*
351 		 * No size were given to '-S' or '-m,', so go with
352 		 * the default
353 		 */
354 		if (!opts->auxtrace_snapshot_size &&
355 		    !opts->auxtrace_mmap_pages) {
356 			if (privileged) {
357 				opts->auxtrace_mmap_pages = MiB(4) / page_size;
358 			} else {
359 				opts->auxtrace_mmap_pages =
360 							KiB(128) / page_size;
361 				if (opts->mmap_pages == UINT_MAX)
362 					opts->mmap_pages = KiB(256) / page_size;
363 			}
364 		} else if (!opts->auxtrace_mmap_pages && !privileged &&
365 						opts->mmap_pages == UINT_MAX) {
366 			opts->mmap_pages = KiB(256) / page_size;
367 		}
368 
369 		/*
370 		 * '-m,xyz' was specified but no snapshot size, so make the
371 		 * snapshot size as big as the auxtrace mmap area.
372 		 */
373 		if (!opts->auxtrace_snapshot_size) {
374 			opts->auxtrace_snapshot_size =
375 				opts->auxtrace_mmap_pages * (size_t)page_size;
376 		}
377 
378 		/*
379 		 * -Sxyz was specified but no auxtrace mmap area, so make the
380 		 * auxtrace mmap area big enough to fit the requested snapshot
381 		 * size.
382 		 */
383 		if (!opts->auxtrace_mmap_pages) {
384 			size_t sz = opts->auxtrace_snapshot_size;
385 
386 			sz = round_up(sz, page_size) / page_size;
387 			opts->auxtrace_mmap_pages = roundup_pow_of_two(sz);
388 		}
389 
390 		/* Snapshot size can't be bigger than the auxtrace area */
391 		if (opts->auxtrace_snapshot_size >
392 				opts->auxtrace_mmap_pages * (size_t)page_size) {
393 			pr_err("Snapshot size %zu must not be greater than AUX area tracing mmap size %zu\n",
394 			       opts->auxtrace_snapshot_size,
395 			       opts->auxtrace_mmap_pages * (size_t)page_size);
396 			return -EINVAL;
397 		}
398 
399 		/* Something went wrong somewhere - this shouldn't happen */
400 		if (!opts->auxtrace_snapshot_size ||
401 		    !opts->auxtrace_mmap_pages) {
402 			pr_err("Failed to calculate default snapshot size and/or AUX area tracing mmap pages\n");
403 			return -EINVAL;
404 		}
405 	}
406 
407 	/* Buffer sizes weren't specified with '-m,xyz' so give some defaults */
408 	if (!opts->auxtrace_mmap_pages) {
409 		if (privileged) {
410 			opts->auxtrace_mmap_pages = MiB(4) / page_size;
411 		} else {
412 			opts->auxtrace_mmap_pages = KiB(128) / page_size;
413 			if (opts->mmap_pages == UINT_MAX)
414 				opts->mmap_pages = KiB(256) / page_size;
415 		}
416 	}
417 
418 	if (opts->auxtrace_snapshot_mode)
419 		pr_debug2("%s snapshot size: %zu\n", CORESIGHT_ETM_PMU_NAME,
420 			  opts->auxtrace_snapshot_size);
421 
422 	/*
423 	 * To obtain the auxtrace buffer file descriptor, the auxtrace
424 	 * event must come first.
425 	 */
426 	evlist__to_front(evlist, cs_etm_evsel);
427 
428 	/*
429 	 * get the CPU on the sample - need it to associate trace ID in the
430 	 * AUX_OUTPUT_HW_ID event, and the AUX event for per-cpu mmaps.
431 	 */
432 	evsel__set_sample_bit(cs_etm_evsel, CPU);
433 
434 	/*
435 	 * Also the case of per-cpu mmaps, need the contextID in order to be notified
436 	 * when a context switch happened.
437 	 */
438 	if (!perf_cpu_map__has_any_cpu_or_is_empty(cpus)) {
439 		evsel__set_config_if_unset(cs_etm_pmu, cs_etm_evsel,
440 					   "timestamp", 1);
441 		evsel__set_config_if_unset(cs_etm_pmu, cs_etm_evsel,
442 					   "contextid", 1);
443 	}
444 
445 	/*
446 	 * When the option '--timestamp' or '-T' is enabled, the PERF_SAMPLE_TIME
447 	 * bit is set for all events.  In this case, always enable Arm CoreSight
448 	 * timestamp tracing.
449 	 */
450 	if (opts->sample_time_set)
451 		evsel__set_config_if_unset(cs_etm_pmu, cs_etm_evsel,
452 					   "timestamp", 1);
453 
454 	/* Add dummy event to keep tracking */
455 	err = parse_event(evlist, "dummy:u");
456 	if (err)
457 		goto out;
458 	evsel = evlist__last(evlist);
459 	evlist__set_tracking_event(evlist, evsel);
460 	evsel->core.attr.freq = 0;
461 	evsel->core.attr.sample_period = 1;
462 
463 	/* In per-cpu case, always need the time of mmap events etc */
464 	if (!perf_cpu_map__has_any_cpu_or_is_empty(cpus))
465 		evsel__set_sample_bit(evsel, TIME);
466 
467 	err = cs_etm_validate_config(itr, cs_etm_evsel);
468 out:
469 	return err;
470 }
471 
472 static u64 cs_etm_get_config(struct auxtrace_record *itr)
473 {
474 	u64 config = 0;
475 	struct cs_etm_recording *ptr =
476 			container_of(itr, struct cs_etm_recording, itr);
477 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
478 	struct evlist *evlist = ptr->evlist;
479 	struct evsel *evsel;
480 
481 	evlist__for_each_entry(evlist, evsel) {
482 		if (evsel->core.attr.type == cs_etm_pmu->type) {
483 			/*
484 			 * Variable perf_event_attr::config is assigned to
485 			 * ETMv3/PTM.  The bit fields have been made to match
486 			 * the ETMv3.5 ETRMCR register specification.  See the
487 			 * PMU_FORMAT_ATTR() declarations in
488 			 * drivers/hwtracing/coresight/coresight-perf.c for
489 			 * details.
490 			 */
491 			config = evsel->core.attr.config;
492 			break;
493 		}
494 	}
495 
496 	return config;
497 }
498 
499 #ifndef BIT
500 #define BIT(N) (1UL << (N))
501 #endif
502 
503 static u64 cs_etmv4_get_config(struct auxtrace_record *itr)
504 {
505 	u64 config = 0;
506 	u64 config_opts = 0;
507 
508 	/*
509 	 * The perf event variable config bits represent both
510 	 * the command line options and register programming
511 	 * bits in ETMv3/PTM. For ETMv4 we must remap options
512 	 * to real bits
513 	 */
514 	config_opts = cs_etm_get_config(itr);
515 	if (config_opts & BIT(ETM_OPT_CYCACC))
516 		config |= BIT(ETM4_CFG_BIT_CYCACC);
517 	if (config_opts & BIT(ETM_OPT_CTXTID))
518 		config |= BIT(ETM4_CFG_BIT_CTXTID);
519 	if (config_opts & BIT(ETM_OPT_TS))
520 		config |= BIT(ETM4_CFG_BIT_TS);
521 	if (config_opts & BIT(ETM_OPT_RETSTK))
522 		config |= BIT(ETM4_CFG_BIT_RETSTK);
523 	if (config_opts & BIT(ETM_OPT_CTXTID2))
524 		config |= BIT(ETM4_CFG_BIT_VMID) |
525 			  BIT(ETM4_CFG_BIT_VMID_OPT);
526 	if (config_opts & BIT(ETM_OPT_BRANCH_BROADCAST))
527 		config |= BIT(ETM4_CFG_BIT_BB);
528 
529 	return config;
530 }
531 
532 static size_t
533 cs_etm_info_priv_size(struct auxtrace_record *itr __maybe_unused,
534 		      struct evlist *evlist __maybe_unused)
535 {
536 	int i;
537 	int etmv3 = 0, etmv4 = 0, ete = 0;
538 	struct perf_cpu_map *event_cpus = evlist->core.user_requested_cpus;
539 	struct perf_cpu_map *online_cpus = perf_cpu_map__new_online_cpus();
540 
541 	/* cpu map is not empty, we have specific CPUs to work with */
542 	if (!perf_cpu_map__has_any_cpu_or_is_empty(event_cpus)) {
543 		for (i = 0; i < cpu__max_cpu().cpu; i++) {
544 			struct perf_cpu cpu = { .cpu = i, };
545 
546 			if (!perf_cpu_map__has(event_cpus, cpu) ||
547 			    !perf_cpu_map__has(online_cpus, cpu))
548 				continue;
549 
550 			if (cs_etm_is_ete(itr, i))
551 				ete++;
552 			else if (cs_etm_is_etmv4(itr, i))
553 				etmv4++;
554 			else
555 				etmv3++;
556 		}
557 	} else {
558 		/* get configuration for all CPUs in the system */
559 		for (i = 0; i < cpu__max_cpu().cpu; i++) {
560 			struct perf_cpu cpu = { .cpu = i, };
561 
562 			if (!perf_cpu_map__has(online_cpus, cpu))
563 				continue;
564 
565 			if (cs_etm_is_ete(itr, i))
566 				ete++;
567 			else if (cs_etm_is_etmv4(itr, i))
568 				etmv4++;
569 			else
570 				etmv3++;
571 		}
572 	}
573 
574 	perf_cpu_map__put(online_cpus);
575 
576 	return (CS_ETM_HEADER_SIZE +
577 	       (ete   * CS_ETE_PRIV_SIZE) +
578 	       (etmv4 * CS_ETMV4_PRIV_SIZE) +
579 	       (etmv3 * CS_ETMV3_PRIV_SIZE));
580 }
581 
582 static bool cs_etm_is_etmv4(struct auxtrace_record *itr, int cpu)
583 {
584 	bool ret = false;
585 	char path[PATH_MAX];
586 	int scan;
587 	unsigned int val;
588 	struct cs_etm_recording *ptr =
589 			container_of(itr, struct cs_etm_recording, itr);
590 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
591 
592 	/* Take any of the RO files for ETMv4 and see if it present */
593 	snprintf(path, PATH_MAX, "cpu%d/%s",
594 		 cpu, metadata_etmv4_ro[CS_ETMV4_TRCIDR0]);
595 	scan = perf_pmu__scan_file(cs_etm_pmu, path, "%x", &val);
596 
597 	/* The file was read successfully, we have a winner */
598 	if (scan == 1)
599 		ret = true;
600 
601 	return ret;
602 }
603 
604 static int cs_etm_get_ro(struct perf_pmu *pmu, int cpu, const char *path)
605 {
606 	char pmu_path[PATH_MAX];
607 	int scan;
608 	unsigned int val = 0;
609 
610 	/* Get RO metadata from sysfs */
611 	snprintf(pmu_path, PATH_MAX, "cpu%d/%s", cpu, path);
612 
613 	scan = perf_pmu__scan_file(pmu, pmu_path, "%x", &val);
614 	if (scan != 1)
615 		pr_err("%s: error reading: %s\n", __func__, pmu_path);
616 
617 	return val;
618 }
619 
620 static int cs_etm_get_ro_signed(struct perf_pmu *pmu, int cpu, const char *path)
621 {
622 	char pmu_path[PATH_MAX];
623 	int scan;
624 	int val = 0;
625 
626 	/* Get RO metadata from sysfs */
627 	snprintf(pmu_path, PATH_MAX, "cpu%d/%s", cpu, path);
628 
629 	scan = perf_pmu__scan_file(pmu, pmu_path, "%d", &val);
630 	if (scan != 1)
631 		pr_err("%s: error reading: %s\n", __func__, pmu_path);
632 
633 	return val;
634 }
635 
636 static bool cs_etm_pmu_path_exists(struct perf_pmu *pmu, int cpu, const char *path)
637 {
638 	char pmu_path[PATH_MAX];
639 
640 	/* Get RO metadata from sysfs */
641 	snprintf(pmu_path, PATH_MAX, "cpu%d/%s", cpu, path);
642 
643 	return perf_pmu__file_exists(pmu, pmu_path);
644 }
645 
646 #define TRCDEVARCH_ARCHPART_SHIFT 0
647 #define TRCDEVARCH_ARCHPART_MASK  GENMASK(11, 0)
648 #define TRCDEVARCH_ARCHPART(x)    (((x) & TRCDEVARCH_ARCHPART_MASK) >> TRCDEVARCH_ARCHPART_SHIFT)
649 
650 #define TRCDEVARCH_ARCHVER_SHIFT 12
651 #define TRCDEVARCH_ARCHVER_MASK  GENMASK(15, 12)
652 #define TRCDEVARCH_ARCHVER(x)    (((x) & TRCDEVARCH_ARCHVER_MASK) >> TRCDEVARCH_ARCHVER_SHIFT)
653 
654 static bool cs_etm_is_ete(struct auxtrace_record *itr, int cpu)
655 {
656 	struct cs_etm_recording *ptr = container_of(itr, struct cs_etm_recording, itr);
657 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
658 	int trcdevarch;
659 
660 	if (!cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCDEVARCH]))
661 		return false;
662 
663 	trcdevarch = cs_etm_get_ro(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TRCDEVARCH]);
664 	/*
665 	 * ETE if ARCHVER is 5 (ARCHVER is 4 for ETM) and ARCHPART is 0xA13.
666 	 * See ETM_DEVARCH_ETE_ARCH in coresight-etm4x.h
667 	 */
668 	return TRCDEVARCH_ARCHVER(trcdevarch) == 5 && TRCDEVARCH_ARCHPART(trcdevarch) == 0xA13;
669 }
670 
671 static void cs_etm_save_etmv4_header(__u64 data[], struct auxtrace_record *itr, int cpu)
672 {
673 	struct cs_etm_recording *ptr = container_of(itr, struct cs_etm_recording, itr);
674 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
675 
676 	/* Get trace configuration register */
677 	data[CS_ETMV4_TRCCONFIGR] = cs_etmv4_get_config(itr);
678 	/* traceID set to legacy version, in case new perf running on older system */
679 	data[CS_ETMV4_TRCTRACEIDR] =
680 		CORESIGHT_LEGACY_CPU_TRACE_ID(cpu) | CORESIGHT_TRACE_ID_UNUSED_FLAG;
681 
682 	/* Get read-only information from sysFS */
683 	data[CS_ETMV4_TRCIDR0] = cs_etm_get_ro(cs_etm_pmu, cpu,
684 					       metadata_etmv4_ro[CS_ETMV4_TRCIDR0]);
685 	data[CS_ETMV4_TRCIDR1] = cs_etm_get_ro(cs_etm_pmu, cpu,
686 					       metadata_etmv4_ro[CS_ETMV4_TRCIDR1]);
687 	data[CS_ETMV4_TRCIDR2] = cs_etm_get_ro(cs_etm_pmu, cpu,
688 					       metadata_etmv4_ro[CS_ETMV4_TRCIDR2]);
689 	data[CS_ETMV4_TRCIDR8] = cs_etm_get_ro(cs_etm_pmu, cpu,
690 					       metadata_etmv4_ro[CS_ETMV4_TRCIDR8]);
691 	data[CS_ETMV4_TRCAUTHSTATUS] = cs_etm_get_ro(cs_etm_pmu, cpu,
692 						     metadata_etmv4_ro[CS_ETMV4_TRCAUTHSTATUS]);
693 
694 	/* Kernels older than 5.19 may not expose ts_source */
695 	if (cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_etmv4_ro[CS_ETMV4_TS_SOURCE]))
696 		data[CS_ETMV4_TS_SOURCE] = (__u64) cs_etm_get_ro_signed(cs_etm_pmu, cpu,
697 				metadata_etmv4_ro[CS_ETMV4_TS_SOURCE]);
698 	else {
699 		pr_debug3("[%03d] pmu file 'ts_source' not found. Fallback to safe value (-1)\n",
700 			  cpu);
701 		data[CS_ETMV4_TS_SOURCE] = (__u64) -1;
702 	}
703 }
704 
705 static void cs_etm_save_ete_header(__u64 data[], struct auxtrace_record *itr, int cpu)
706 {
707 	struct cs_etm_recording *ptr = container_of(itr, struct cs_etm_recording, itr);
708 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
709 
710 	/* Get trace configuration register */
711 	data[CS_ETE_TRCCONFIGR] = cs_etmv4_get_config(itr);
712 	/* traceID set to legacy version, in case new perf running on older system */
713 	data[CS_ETE_TRCTRACEIDR] =
714 		CORESIGHT_LEGACY_CPU_TRACE_ID(cpu) | CORESIGHT_TRACE_ID_UNUSED_FLAG;
715 
716 	/* Get read-only information from sysFS */
717 	data[CS_ETE_TRCIDR0] = cs_etm_get_ro(cs_etm_pmu, cpu,
718 					     metadata_ete_ro[CS_ETE_TRCIDR0]);
719 	data[CS_ETE_TRCIDR1] = cs_etm_get_ro(cs_etm_pmu, cpu,
720 					     metadata_ete_ro[CS_ETE_TRCIDR1]);
721 	data[CS_ETE_TRCIDR2] = cs_etm_get_ro(cs_etm_pmu, cpu,
722 					     metadata_ete_ro[CS_ETE_TRCIDR2]);
723 	data[CS_ETE_TRCIDR8] = cs_etm_get_ro(cs_etm_pmu, cpu,
724 					     metadata_ete_ro[CS_ETE_TRCIDR8]);
725 	data[CS_ETE_TRCAUTHSTATUS] = cs_etm_get_ro(cs_etm_pmu, cpu,
726 						   metadata_ete_ro[CS_ETE_TRCAUTHSTATUS]);
727 	/* ETE uses the same registers as ETMv4 plus TRCDEVARCH */
728 	data[CS_ETE_TRCDEVARCH] = cs_etm_get_ro(cs_etm_pmu, cpu,
729 						metadata_ete_ro[CS_ETE_TRCDEVARCH]);
730 
731 	/* Kernels older than 5.19 may not expose ts_source */
732 	if (cs_etm_pmu_path_exists(cs_etm_pmu, cpu, metadata_ete_ro[CS_ETE_TS_SOURCE]))
733 		data[CS_ETE_TS_SOURCE] = (__u64) cs_etm_get_ro_signed(cs_etm_pmu, cpu,
734 				metadata_ete_ro[CS_ETE_TS_SOURCE]);
735 	else {
736 		pr_debug3("[%03d] pmu file 'ts_source' not found. Fallback to safe value (-1)\n",
737 			  cpu);
738 		data[CS_ETE_TS_SOURCE] = (__u64) -1;
739 	}
740 }
741 
742 static void cs_etm_get_metadata(int cpu, u32 *offset,
743 				struct auxtrace_record *itr,
744 				struct perf_record_auxtrace_info *info)
745 {
746 	u32 increment, nr_trc_params;
747 	u64 magic;
748 	struct cs_etm_recording *ptr =
749 			container_of(itr, struct cs_etm_recording, itr);
750 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
751 
752 	/* first see what kind of tracer this cpu is affined to */
753 	if (cs_etm_is_ete(itr, cpu)) {
754 		magic = __perf_cs_ete_magic;
755 		cs_etm_save_ete_header(&info->priv[*offset], itr, cpu);
756 
757 		/* How much space was used */
758 		increment = CS_ETE_PRIV_MAX;
759 		nr_trc_params = CS_ETE_PRIV_MAX - CS_ETM_COMMON_BLK_MAX_V1;
760 	} else if (cs_etm_is_etmv4(itr, cpu)) {
761 		magic = __perf_cs_etmv4_magic;
762 		cs_etm_save_etmv4_header(&info->priv[*offset], itr, cpu);
763 
764 		/* How much space was used */
765 		increment = CS_ETMV4_PRIV_MAX;
766 		nr_trc_params = CS_ETMV4_PRIV_MAX - CS_ETMV4_TRCCONFIGR;
767 	} else {
768 		magic = __perf_cs_etmv3_magic;
769 		/* Get configuration register */
770 		info->priv[*offset + CS_ETM_ETMCR] = cs_etm_get_config(itr);
771 		/* traceID set to legacy value in case new perf running on old system */
772 		info->priv[*offset + CS_ETM_ETMTRACEIDR] =
773 			CORESIGHT_LEGACY_CPU_TRACE_ID(cpu) | CORESIGHT_TRACE_ID_UNUSED_FLAG;
774 		/* Get read-only information from sysFS */
775 		info->priv[*offset + CS_ETM_ETMCCER] =
776 			cs_etm_get_ro(cs_etm_pmu, cpu,
777 				      metadata_etmv3_ro[CS_ETM_ETMCCER]);
778 		info->priv[*offset + CS_ETM_ETMIDR] =
779 			cs_etm_get_ro(cs_etm_pmu, cpu,
780 				      metadata_etmv3_ro[CS_ETM_ETMIDR]);
781 
782 		/* How much space was used */
783 		increment = CS_ETM_PRIV_MAX;
784 		nr_trc_params = CS_ETM_PRIV_MAX - CS_ETM_ETMCR;
785 	}
786 
787 	/* Build generic header portion */
788 	info->priv[*offset + CS_ETM_MAGIC] = magic;
789 	info->priv[*offset + CS_ETM_CPU] = cpu;
790 	info->priv[*offset + CS_ETM_NR_TRC_PARAMS] = nr_trc_params;
791 	/* Where the next CPU entry should start from */
792 	*offset += increment;
793 }
794 
795 static int cs_etm_info_fill(struct auxtrace_record *itr,
796 			    struct perf_session *session,
797 			    struct perf_record_auxtrace_info *info,
798 			    size_t priv_size)
799 {
800 	int i;
801 	u32 offset;
802 	u64 nr_cpu, type;
803 	struct perf_cpu_map *cpu_map;
804 	struct perf_cpu_map *event_cpus = session->evlist->core.user_requested_cpus;
805 	struct perf_cpu_map *online_cpus = perf_cpu_map__new_online_cpus();
806 	struct cs_etm_recording *ptr =
807 			container_of(itr, struct cs_etm_recording, itr);
808 	struct perf_pmu *cs_etm_pmu = ptr->cs_etm_pmu;
809 
810 	if (priv_size != cs_etm_info_priv_size(itr, session->evlist))
811 		return -EINVAL;
812 
813 	if (!session->evlist->core.nr_mmaps)
814 		return -EINVAL;
815 
816 	/* If the cpu_map is empty all online CPUs are involved */
817 	if (perf_cpu_map__has_any_cpu_or_is_empty(event_cpus)) {
818 		cpu_map = online_cpus;
819 	} else {
820 		/* Make sure all specified CPUs are online */
821 		for (i = 0; i < perf_cpu_map__nr(event_cpus); i++) {
822 			struct perf_cpu cpu = { .cpu = i, };
823 
824 			if (perf_cpu_map__has(event_cpus, cpu) &&
825 			    !perf_cpu_map__has(online_cpus, cpu))
826 				return -EINVAL;
827 		}
828 
829 		cpu_map = event_cpus;
830 	}
831 
832 	nr_cpu = perf_cpu_map__nr(cpu_map);
833 	/* Get PMU type as dynamically assigned by the core */
834 	type = cs_etm_pmu->type;
835 
836 	/* First fill out the session header */
837 	info->type = PERF_AUXTRACE_CS_ETM;
838 	info->priv[CS_HEADER_VERSION] = CS_HEADER_CURRENT_VERSION;
839 	info->priv[CS_PMU_TYPE_CPUS] = type << 32;
840 	info->priv[CS_PMU_TYPE_CPUS] |= nr_cpu;
841 	info->priv[CS_ETM_SNAPSHOT] = ptr->snapshot_mode;
842 
843 	offset = CS_ETM_SNAPSHOT + 1;
844 
845 	for (i = 0; i < cpu__max_cpu().cpu && offset < priv_size; i++) {
846 		struct perf_cpu cpu = { .cpu = i, };
847 
848 		if (perf_cpu_map__has(cpu_map, cpu))
849 			cs_etm_get_metadata(i, &offset, itr, info);
850 	}
851 
852 	perf_cpu_map__put(online_cpus);
853 
854 	return 0;
855 }
856 
857 static int cs_etm_snapshot_start(struct auxtrace_record *itr)
858 {
859 	struct cs_etm_recording *ptr =
860 			container_of(itr, struct cs_etm_recording, itr);
861 	struct evsel *evsel;
862 
863 	evlist__for_each_entry(ptr->evlist, evsel) {
864 		if (evsel->core.attr.type == ptr->cs_etm_pmu->type)
865 			return evsel__disable(evsel);
866 	}
867 	return -EINVAL;
868 }
869 
870 static int cs_etm_snapshot_finish(struct auxtrace_record *itr)
871 {
872 	struct cs_etm_recording *ptr =
873 			container_of(itr, struct cs_etm_recording, itr);
874 	struct evsel *evsel;
875 
876 	evlist__for_each_entry(ptr->evlist, evsel) {
877 		if (evsel->core.attr.type == ptr->cs_etm_pmu->type)
878 			return evsel__enable(evsel);
879 	}
880 	return -EINVAL;
881 }
882 
883 static u64 cs_etm_reference(struct auxtrace_record *itr __maybe_unused)
884 {
885 	return (((u64) rand() <<  0) & 0x00000000FFFFFFFFull) |
886 		(((u64) rand() << 32) & 0xFFFFFFFF00000000ull);
887 }
888 
889 static void cs_etm_recording_free(struct auxtrace_record *itr)
890 {
891 	struct cs_etm_recording *ptr =
892 			container_of(itr, struct cs_etm_recording, itr);
893 
894 	free(ptr);
895 }
896 
897 struct auxtrace_record *cs_etm_record_init(int *err)
898 {
899 	struct perf_pmu *cs_etm_pmu;
900 	struct cs_etm_recording *ptr;
901 
902 	cs_etm_pmu = perf_pmus__find(CORESIGHT_ETM_PMU_NAME);
903 
904 	if (!cs_etm_pmu) {
905 		*err = -EINVAL;
906 		goto out;
907 	}
908 
909 	ptr = zalloc(sizeof(struct cs_etm_recording));
910 	if (!ptr) {
911 		*err = -ENOMEM;
912 		goto out;
913 	}
914 
915 	ptr->cs_etm_pmu			= cs_etm_pmu;
916 	ptr->itr.pmu			= cs_etm_pmu;
917 	ptr->itr.parse_snapshot_options	= cs_etm_parse_snapshot_options;
918 	ptr->itr.recording_options	= cs_etm_recording_options;
919 	ptr->itr.info_priv_size		= cs_etm_info_priv_size;
920 	ptr->itr.info_fill		= cs_etm_info_fill;
921 	ptr->itr.snapshot_start		= cs_etm_snapshot_start;
922 	ptr->itr.snapshot_finish	= cs_etm_snapshot_finish;
923 	ptr->itr.reference		= cs_etm_reference;
924 	ptr->itr.free			= cs_etm_recording_free;
925 	ptr->itr.read_finish		= auxtrace_record__read_finish;
926 
927 	*err = 0;
928 	return &ptr->itr;
929 out:
930 	return NULL;
931 }
932 
933 /*
934  * Set a default config to enable the user changed config tracking mechanism
935  * (CFG_CHG and evsel__set_config_if_unset()). If no default is set then user
936  * changes aren't tracked.
937  */
938 void
939 cs_etm_get_default_config(const struct perf_pmu *pmu __maybe_unused,
940 			  struct perf_event_attr *attr)
941 {
942 	attr->sample_period = 1;
943 }
944