xref: /linux/tools/perf/util/arm-spe-decoder/arm-spe-pkt-decoder.c (revision 90d32e92011eaae8e70a9169b4e7acf4ca8f9d3a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Arm Statistical Profiling Extensions (SPE) support
4  * Copyright (c) 2017-2018, Arm Ltd.
5  */
6 
7 #include <stdio.h>
8 #include <string.h>
9 #include <endian.h>
10 #include <byteswap.h>
11 #include <linux/bitops.h>
12 #include <stdarg.h>
13 #include <linux/kernel.h>
14 #include <asm-generic/unaligned.h>
15 
16 #include "arm-spe-pkt-decoder.h"
17 
18 static const char * const arm_spe_packet_name[] = {
19 	[ARM_SPE_PAD]		= "PAD",
20 	[ARM_SPE_END]		= "END",
21 	[ARM_SPE_TIMESTAMP]	= "TS",
22 	[ARM_SPE_ADDRESS]	= "ADDR",
23 	[ARM_SPE_COUNTER]	= "LAT",
24 	[ARM_SPE_CONTEXT]	= "CONTEXT",
25 	[ARM_SPE_OP_TYPE]	= "OP-TYPE",
26 	[ARM_SPE_EVENTS]	= "EVENTS",
27 	[ARM_SPE_DATA_SOURCE]	= "DATA-SOURCE",
28 };
29 
30 const char *arm_spe_pkt_name(enum arm_spe_pkt_type type)
31 {
32 	return arm_spe_packet_name[type];
33 }
34 
35 /*
36  * Extracts the field "sz" from header bits and converts to bytes:
37  *   00 : byte (1)
38  *   01 : halfword (2)
39  *   10 : word (4)
40  *   11 : doubleword (8)
41  */
42 static unsigned int arm_spe_payload_len(unsigned char hdr)
43 {
44 	return 1U << ((hdr & GENMASK_ULL(5, 4)) >> 4);
45 }
46 
47 static int arm_spe_get_payload(const unsigned char *buf, size_t len,
48 			       unsigned char ext_hdr,
49 			       struct arm_spe_pkt *packet)
50 {
51 	size_t payload_len = arm_spe_payload_len(buf[ext_hdr]);
52 
53 	if (len < 1 + ext_hdr + payload_len)
54 		return ARM_SPE_NEED_MORE_BYTES;
55 
56 	buf += 1 + ext_hdr;
57 
58 	switch (payload_len) {
59 	case 1: packet->payload = *(uint8_t *)buf; break;
60 	case 2: packet->payload = get_unaligned_le16(buf); break;
61 	case 4: packet->payload = get_unaligned_le32(buf); break;
62 	case 8: packet->payload = get_unaligned_le64(buf); break;
63 	default: return ARM_SPE_BAD_PACKET;
64 	}
65 
66 	return 1 + ext_hdr + payload_len;
67 }
68 
69 static int arm_spe_get_pad(struct arm_spe_pkt *packet)
70 {
71 	packet->type = ARM_SPE_PAD;
72 	return 1;
73 }
74 
75 static int arm_spe_get_alignment(const unsigned char *buf, size_t len,
76 				 struct arm_spe_pkt *packet)
77 {
78 	unsigned int alignment = 1 << ((buf[0] & 0xf) + 1);
79 
80 	if (len < alignment)
81 		return ARM_SPE_NEED_MORE_BYTES;
82 
83 	packet->type = ARM_SPE_PAD;
84 	return alignment - (((uintptr_t)buf) & (alignment - 1));
85 }
86 
87 static int arm_spe_get_end(struct arm_spe_pkt *packet)
88 {
89 	packet->type = ARM_SPE_END;
90 	return 1;
91 }
92 
93 static int arm_spe_get_timestamp(const unsigned char *buf, size_t len,
94 				 struct arm_spe_pkt *packet)
95 {
96 	packet->type = ARM_SPE_TIMESTAMP;
97 	return arm_spe_get_payload(buf, len, 0, packet);
98 }
99 
100 static int arm_spe_get_events(const unsigned char *buf, size_t len,
101 			      struct arm_spe_pkt *packet)
102 {
103 	packet->type = ARM_SPE_EVENTS;
104 
105 	/* we use index to identify Events with a less number of
106 	 * comparisons in arm_spe_pkt_desc(): E.g., the LLC-ACCESS,
107 	 * LLC-REFILL, and REMOTE-ACCESS events are identified if
108 	 * index > 1.
109 	 */
110 	packet->index = arm_spe_payload_len(buf[0]);
111 
112 	return arm_spe_get_payload(buf, len, 0, packet);
113 }
114 
115 static int arm_spe_get_data_source(const unsigned char *buf, size_t len,
116 				   struct arm_spe_pkt *packet)
117 {
118 	packet->type = ARM_SPE_DATA_SOURCE;
119 	return arm_spe_get_payload(buf, len, 0, packet);
120 }
121 
122 static int arm_spe_get_context(const unsigned char *buf, size_t len,
123 			       struct arm_spe_pkt *packet)
124 {
125 	packet->type = ARM_SPE_CONTEXT;
126 	packet->index = SPE_CTX_PKT_HDR_INDEX(buf[0]);
127 	return arm_spe_get_payload(buf, len, 0, packet);
128 }
129 
130 static int arm_spe_get_op_type(const unsigned char *buf, size_t len,
131 			       struct arm_spe_pkt *packet)
132 {
133 	packet->type = ARM_SPE_OP_TYPE;
134 	packet->index = SPE_OP_PKT_HDR_CLASS(buf[0]);
135 	return arm_spe_get_payload(buf, len, 0, packet);
136 }
137 
138 static int arm_spe_get_counter(const unsigned char *buf, size_t len,
139 			       const unsigned char ext_hdr, struct arm_spe_pkt *packet)
140 {
141 	packet->type = ARM_SPE_COUNTER;
142 
143 	if (ext_hdr)
144 		packet->index = SPE_HDR_EXTENDED_INDEX(buf[0], buf[1]);
145 	else
146 		packet->index = SPE_HDR_SHORT_INDEX(buf[0]);
147 
148 	return arm_spe_get_payload(buf, len, ext_hdr, packet);
149 }
150 
151 static int arm_spe_get_addr(const unsigned char *buf, size_t len,
152 			    const unsigned char ext_hdr, struct arm_spe_pkt *packet)
153 {
154 	packet->type = ARM_SPE_ADDRESS;
155 
156 	if (ext_hdr)
157 		packet->index = SPE_HDR_EXTENDED_INDEX(buf[0], buf[1]);
158 	else
159 		packet->index = SPE_HDR_SHORT_INDEX(buf[0]);
160 
161 	return arm_spe_get_payload(buf, len, ext_hdr, packet);
162 }
163 
164 static int arm_spe_do_get_packet(const unsigned char *buf, size_t len,
165 				 struct arm_spe_pkt *packet)
166 {
167 	unsigned int hdr;
168 	unsigned char ext_hdr = 0;
169 
170 	memset(packet, 0, sizeof(struct arm_spe_pkt));
171 
172 	if (!len)
173 		return ARM_SPE_NEED_MORE_BYTES;
174 
175 	hdr = buf[0];
176 
177 	if (hdr == SPE_HEADER0_PAD)
178 		return arm_spe_get_pad(packet);
179 
180 	if (hdr == SPE_HEADER0_END) /* no timestamp at end of record */
181 		return arm_spe_get_end(packet);
182 
183 	if (hdr == SPE_HEADER0_TIMESTAMP)
184 		return arm_spe_get_timestamp(buf, len, packet);
185 
186 	if ((hdr & SPE_HEADER0_MASK1) == SPE_HEADER0_EVENTS)
187 		return arm_spe_get_events(buf, len, packet);
188 
189 	if ((hdr & SPE_HEADER0_MASK1) == SPE_HEADER0_SOURCE)
190 		return arm_spe_get_data_source(buf, len, packet);
191 
192 	if ((hdr & SPE_HEADER0_MASK2) == SPE_HEADER0_CONTEXT)
193 		return arm_spe_get_context(buf, len, packet);
194 
195 	if ((hdr & SPE_HEADER0_MASK2) == SPE_HEADER0_OP_TYPE)
196 		return arm_spe_get_op_type(buf, len, packet);
197 
198 	if ((hdr & SPE_HEADER0_MASK2) == SPE_HEADER0_EXTENDED) {
199 		/* 16-bit extended format header */
200 		if (len == 1)
201 			return ARM_SPE_BAD_PACKET;
202 
203 		ext_hdr = 1;
204 		hdr = buf[1];
205 		if (hdr == SPE_HEADER1_ALIGNMENT)
206 			return arm_spe_get_alignment(buf, len, packet);
207 	}
208 
209 	/*
210 	 * The short format header's byte 0 or the extended format header's
211 	 * byte 1 has been assigned to 'hdr', which uses the same encoding for
212 	 * address packet and counter packet, so don't need to distinguish if
213 	 * it's short format or extended format and handle in once.
214 	 */
215 	if ((hdr & SPE_HEADER0_MASK3) == SPE_HEADER0_ADDRESS)
216 		return arm_spe_get_addr(buf, len, ext_hdr, packet);
217 
218 	if ((hdr & SPE_HEADER0_MASK3) == SPE_HEADER0_COUNTER)
219 		return arm_spe_get_counter(buf, len, ext_hdr, packet);
220 
221 	return ARM_SPE_BAD_PACKET;
222 }
223 
224 int arm_spe_get_packet(const unsigned char *buf, size_t len,
225 		       struct arm_spe_pkt *packet)
226 {
227 	int ret;
228 
229 	ret = arm_spe_do_get_packet(buf, len, packet);
230 	/* put multiple consecutive PADs on the same line, up to
231 	 * the fixed-width output format of 16 bytes per line.
232 	 */
233 	if (ret > 0 && packet->type == ARM_SPE_PAD) {
234 		while (ret < 16 && len > (size_t)ret && !buf[ret])
235 			ret += 1;
236 	}
237 	return ret;
238 }
239 
240 static int arm_spe_pkt_out_string(int *err, char **buf_p, size_t *blen,
241 				  const char *fmt, ...)
242 {
243 	va_list ap;
244 	int ret;
245 
246 	/* Bail out if any error occurred */
247 	if (err && *err)
248 		return *err;
249 
250 	va_start(ap, fmt);
251 	ret = vsnprintf(*buf_p, *blen, fmt, ap);
252 	va_end(ap);
253 
254 	if (ret < 0) {
255 		if (err && !*err)
256 			*err = ret;
257 
258 	/*
259 	 * A return value of *blen or more means that the output was
260 	 * truncated and the buffer is overrun.
261 	 */
262 	} else if ((size_t)ret >= *blen) {
263 		(*buf_p)[*blen - 1] = '\0';
264 
265 		/*
266 		 * Set *err to 'ret' to avoid overflow if tries to
267 		 * fill this buffer sequentially.
268 		 */
269 		if (err && !*err)
270 			*err = ret;
271 	} else {
272 		*buf_p += ret;
273 		*blen -= ret;
274 	}
275 
276 	return ret;
277 }
278 
279 static int arm_spe_pkt_desc_event(const struct arm_spe_pkt *packet,
280 				  char *buf, size_t buf_len)
281 {
282 	u64 payload = packet->payload;
283 	int err = 0;
284 
285 	arm_spe_pkt_out_string(&err, &buf, &buf_len, "EV");
286 
287 	if (payload & BIT(EV_EXCEPTION_GEN))
288 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " EXCEPTION-GEN");
289 	if (payload & BIT(EV_RETIRED))
290 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " RETIRED");
291 	if (payload & BIT(EV_L1D_ACCESS))
292 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " L1D-ACCESS");
293 	if (payload & BIT(EV_L1D_REFILL))
294 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " L1D-REFILL");
295 	if (payload & BIT(EV_TLB_ACCESS))
296 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " TLB-ACCESS");
297 	if (payload & BIT(EV_TLB_WALK))
298 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " TLB-REFILL");
299 	if (payload & BIT(EV_NOT_TAKEN))
300 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " NOT-TAKEN");
301 	if (payload & BIT(EV_MISPRED))
302 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " MISPRED");
303 	if (payload & BIT(EV_LLC_ACCESS))
304 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " LLC-ACCESS");
305 	if (payload & BIT(EV_LLC_MISS))
306 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " LLC-REFILL");
307 	if (payload & BIT(EV_REMOTE_ACCESS))
308 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " REMOTE-ACCESS");
309 	if (payload & BIT(EV_ALIGNMENT))
310 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " ALIGNMENT");
311 	if (payload & BIT(EV_PARTIAL_PREDICATE))
312 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " SVE-PARTIAL-PRED");
313 	if (payload & BIT(EV_EMPTY_PREDICATE))
314 		arm_spe_pkt_out_string(&err, &buf, &buf_len, " SVE-EMPTY-PRED");
315 
316 	return err;
317 }
318 
319 static int arm_spe_pkt_desc_op_type(const struct arm_spe_pkt *packet,
320 				    char *buf, size_t buf_len)
321 {
322 	u64 payload = packet->payload;
323 	int err = 0;
324 
325 	switch (packet->index) {
326 	case SPE_OP_PKT_HDR_CLASS_OTHER:
327 		if (SPE_OP_PKT_IS_OTHER_SVE_OP(payload)) {
328 			arm_spe_pkt_out_string(&err, &buf, &buf_len, "SVE-OTHER");
329 
330 			/* SVE effective vector length */
331 			arm_spe_pkt_out_string(&err, &buf, &buf_len, " EVLEN %d",
332 					       SPE_OP_PKG_SVE_EVL(payload));
333 
334 			if (payload & SPE_OP_PKT_SVE_FP)
335 				arm_spe_pkt_out_string(&err, &buf, &buf_len, " FP");
336 			if (payload & SPE_OP_PKT_SVE_PRED)
337 				arm_spe_pkt_out_string(&err, &buf, &buf_len, " PRED");
338 		} else {
339 			arm_spe_pkt_out_string(&err, &buf, &buf_len, "OTHER");
340 			arm_spe_pkt_out_string(&err, &buf, &buf_len, " %s",
341 					       payload & SPE_OP_PKT_COND ?
342 					       "COND-SELECT" : "INSN-OTHER");
343 		}
344 		break;
345 	case SPE_OP_PKT_HDR_CLASS_LD_ST_ATOMIC:
346 		arm_spe_pkt_out_string(&err, &buf, &buf_len,
347 				       payload & 0x1 ? "ST" : "LD");
348 
349 		if (SPE_OP_PKT_IS_LDST_ATOMIC(payload)) {
350 			if (payload & SPE_OP_PKT_AT)
351 				arm_spe_pkt_out_string(&err, &buf, &buf_len, " AT");
352 			if (payload & SPE_OP_PKT_EXCL)
353 				arm_spe_pkt_out_string(&err, &buf, &buf_len, " EXCL");
354 			if (payload & SPE_OP_PKT_AR)
355 				arm_spe_pkt_out_string(&err, &buf, &buf_len, " AR");
356 		}
357 
358 		switch (SPE_OP_PKT_LDST_SUBCLASS_GET(payload)) {
359 		case SPE_OP_PKT_LDST_SUBCLASS_SIMD_FP:
360 			arm_spe_pkt_out_string(&err, &buf, &buf_len, " SIMD-FP");
361 			break;
362 		case SPE_OP_PKT_LDST_SUBCLASS_GP_REG:
363 			arm_spe_pkt_out_string(&err, &buf, &buf_len, " GP-REG");
364 			break;
365 		case SPE_OP_PKT_LDST_SUBCLASS_UNSPEC_REG:
366 			arm_spe_pkt_out_string(&err, &buf, &buf_len, " UNSPEC-REG");
367 			break;
368 		case SPE_OP_PKT_LDST_SUBCLASS_NV_SYSREG:
369 			arm_spe_pkt_out_string(&err, &buf, &buf_len, " NV-SYSREG");
370 			break;
371 		case SPE_OP_PKT_LDST_SUBCLASS_MTE_TAG:
372 			arm_spe_pkt_out_string(&err, &buf, &buf_len, " MTE-TAG");
373 			break;
374 		case SPE_OP_PKT_LDST_SUBCLASS_MEMCPY:
375 			arm_spe_pkt_out_string(&err, &buf, &buf_len, " MEMCPY");
376 			break;
377 		case SPE_OP_PKT_LDST_SUBCLASS_MEMSET:
378 			arm_spe_pkt_out_string(&err, &buf, &buf_len, " MEMSET");
379 			break;
380 		default:
381 			break;
382 		}
383 
384 		if (SPE_OP_PKT_IS_LDST_SVE(payload)) {
385 			/* SVE effective vector length */
386 			arm_spe_pkt_out_string(&err, &buf, &buf_len, " EVLEN %d",
387 					       SPE_OP_PKG_SVE_EVL(payload));
388 
389 			if (payload & SPE_OP_PKT_SVE_PRED)
390 				arm_spe_pkt_out_string(&err, &buf, &buf_len, " PRED");
391 			if (payload & SPE_OP_PKT_SVE_SG)
392 				arm_spe_pkt_out_string(&err, &buf, &buf_len, " SG");
393 		}
394 		break;
395 	case SPE_OP_PKT_HDR_CLASS_BR_ERET:
396 		arm_spe_pkt_out_string(&err, &buf, &buf_len, "B");
397 
398 		if (payload & SPE_OP_PKT_COND)
399 			arm_spe_pkt_out_string(&err, &buf, &buf_len, " COND");
400 
401 		if (SPE_OP_PKT_IS_INDIRECT_BRANCH(payload))
402 			arm_spe_pkt_out_string(&err, &buf, &buf_len, " IND");
403 
404 		break;
405 	default:
406 		/* Unknown index */
407 		err = -1;
408 		break;
409 	}
410 
411 	return err;
412 }
413 
414 static int arm_spe_pkt_desc_addr(const struct arm_spe_pkt *packet,
415 				 char *buf, size_t buf_len)
416 {
417 	int ns, el, idx = packet->index;
418 	int ch, pat;
419 	u64 payload = packet->payload;
420 	int err = 0;
421 	static const char *idx_name[] = {"PC", "TGT", "VA", "PA", "PBT"};
422 
423 	switch (idx) {
424 	case SPE_ADDR_PKT_HDR_INDEX_INS:
425 	case SPE_ADDR_PKT_HDR_INDEX_BRANCH:
426 	case SPE_ADDR_PKT_HDR_INDEX_PREV_BRANCH:
427 		ns = !!SPE_ADDR_PKT_GET_NS(payload);
428 		el = SPE_ADDR_PKT_GET_EL(payload);
429 		payload = SPE_ADDR_PKT_ADDR_GET_BYTES_0_6(payload);
430 		arm_spe_pkt_out_string(&err, &buf, &buf_len,
431 				"%s 0x%llx el%d ns=%d",
432 				idx_name[idx], payload, el, ns);
433 		break;
434 	case SPE_ADDR_PKT_HDR_INDEX_DATA_VIRT:
435 		arm_spe_pkt_out_string(&err, &buf, &buf_len,
436 				       "VA 0x%llx", payload);
437 		break;
438 	case SPE_ADDR_PKT_HDR_INDEX_DATA_PHYS:
439 		ns = !!SPE_ADDR_PKT_GET_NS(payload);
440 		ch = !!SPE_ADDR_PKT_GET_CH(payload);
441 		pat = SPE_ADDR_PKT_GET_PAT(payload);
442 		payload = SPE_ADDR_PKT_ADDR_GET_BYTES_0_6(payload);
443 		arm_spe_pkt_out_string(&err, &buf, &buf_len,
444 				       "PA 0x%llx ns=%d ch=%d pat=%x",
445 				       payload, ns, ch, pat);
446 		break;
447 	default:
448 		/* Unknown index */
449 		err = -1;
450 		break;
451 	}
452 
453 	return err;
454 }
455 
456 static int arm_spe_pkt_desc_counter(const struct arm_spe_pkt *packet,
457 				    char *buf, size_t buf_len)
458 {
459 	u64 payload = packet->payload;
460 	const char *name = arm_spe_pkt_name(packet->type);
461 	int err = 0;
462 
463 	arm_spe_pkt_out_string(&err, &buf, &buf_len, "%s %d ", name,
464 			       (unsigned short)payload);
465 
466 	switch (packet->index) {
467 	case SPE_CNT_PKT_HDR_INDEX_TOTAL_LAT:
468 		arm_spe_pkt_out_string(&err, &buf, &buf_len, "TOT");
469 		break;
470 	case SPE_CNT_PKT_HDR_INDEX_ISSUE_LAT:
471 		arm_spe_pkt_out_string(&err, &buf, &buf_len, "ISSUE");
472 		break;
473 	case SPE_CNT_PKT_HDR_INDEX_TRANS_LAT:
474 		arm_spe_pkt_out_string(&err, &buf, &buf_len, "XLAT");
475 		break;
476 	default:
477 		break;
478 	}
479 
480 	return err;
481 }
482 
483 int arm_spe_pkt_desc(const struct arm_spe_pkt *packet, char *buf,
484 		     size_t buf_len)
485 {
486 	int idx = packet->index;
487 	unsigned long long payload = packet->payload;
488 	const char *name = arm_spe_pkt_name(packet->type);
489 	char *buf_orig = buf;
490 	size_t blen = buf_len;
491 	int err = 0;
492 
493 	switch (packet->type) {
494 	case ARM_SPE_BAD:
495 	case ARM_SPE_PAD:
496 	case ARM_SPE_END:
497 		arm_spe_pkt_out_string(&err, &buf, &blen, "%s", name);
498 		break;
499 	case ARM_SPE_EVENTS:
500 		err = arm_spe_pkt_desc_event(packet, buf, buf_len);
501 		break;
502 	case ARM_SPE_OP_TYPE:
503 		err = arm_spe_pkt_desc_op_type(packet, buf, buf_len);
504 		break;
505 	case ARM_SPE_DATA_SOURCE:
506 	case ARM_SPE_TIMESTAMP:
507 		arm_spe_pkt_out_string(&err, &buf, &blen, "%s %lld", name, payload);
508 		break;
509 	case ARM_SPE_ADDRESS:
510 		err = arm_spe_pkt_desc_addr(packet, buf, buf_len);
511 		break;
512 	case ARM_SPE_CONTEXT:
513 		arm_spe_pkt_out_string(&err, &buf, &blen, "%s 0x%lx el%d",
514 				       name, (unsigned long)payload, idx + 1);
515 		break;
516 	case ARM_SPE_COUNTER:
517 		err = arm_spe_pkt_desc_counter(packet, buf, buf_len);
518 		break;
519 	default:
520 		/* Unknown packet type */
521 		err = -1;
522 		break;
523 	}
524 
525 	/* Output raw data if detect any error */
526 	if (err) {
527 		err = 0;
528 		arm_spe_pkt_out_string(&err, &buf_orig, &buf_len, "%s 0x%llx (%d)",
529 				       name, payload, packet->index);
530 	}
531 
532 	return err;
533 }
534