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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 <linux/unaligned.h>
15
16#include "arm-spe-pkt-decoder.h"
17
18static 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
30const 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 */
42static unsigned int arm_spe_payload_len(unsigned char hdr)
43{
44 return 1U << ((hdr & GENMASK_ULL(5, 4)) >> 4);
45}
46
47static 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
69static int arm_spe_get_pad(struct arm_spe_pkt *packet)
70{
71 packet->type = ARM_SPE_PAD;
72 return 1;
73}
74
75static 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
87static int arm_spe_get_end(struct arm_spe_pkt *packet)
88{
89 packet->type = ARM_SPE_END;
90 return 1;
91}
92
93static 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
100static 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
115static 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
122static 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
130static 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
138static 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
151static 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
164static 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
224int 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
240static 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
279static 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
319static 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
414static 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
456static 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
483int 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}