1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2011-2012, The Linux Foundation. All rights reserved. 4 * 5 * Description: CoreSight Program Flow Trace driver 6 */ 7 8 #include <linux/kernel.h> 9 #include <linux/moduleparam.h> 10 #include <linux/init.h> 11 #include <linux/types.h> 12 #include <linux/device.h> 13 #include <linux/io.h> 14 #include <linux/err.h> 15 #include <linux/fs.h> 16 #include <linux/slab.h> 17 #include <linux/delay.h> 18 #include <linux/smp.h> 19 #include <linux/sysfs.h> 20 #include <linux/stat.h> 21 #include <linux/pm_runtime.h> 22 #include <linux/cpu.h> 23 #include <linux/of.h> 24 #include <linux/coresight.h> 25 #include <linux/coresight-pmu.h> 26 #include <linux/amba/bus.h> 27 #include <linux/seq_file.h> 28 #include <linux/uaccess.h> 29 #include <linux/clk.h> 30 #include <linux/perf_event.h> 31 #include <asm/sections.h> 32 33 #include "coresight-etm.h" 34 #include "coresight-etm-perf.h" 35 36 /* 37 * Not really modular but using module_param is the easiest way to 38 * remain consistent with existing use cases for now. 39 */ 40 static int boot_enable; 41 module_param_named(boot_enable, boot_enable, int, S_IRUGO); 42 43 static struct etm_drvdata *etmdrvdata[NR_CPUS]; 44 45 static enum cpuhp_state hp_online; 46 47 /* 48 * Memory mapped writes to clear os lock are not supported on some processors 49 * and OS lock must be unlocked before any memory mapped access on such 50 * processors, otherwise memory mapped reads/writes will be invalid. 51 */ 52 static void etm_os_unlock(struct etm_drvdata *drvdata) 53 { 54 /* Writing any value to ETMOSLAR unlocks the trace registers */ 55 etm_writel(drvdata, 0x0, ETMOSLAR); 56 drvdata->os_unlock = true; 57 isb(); 58 } 59 60 static void etm_set_pwrdwn(struct etm_drvdata *drvdata) 61 { 62 u32 etmcr; 63 64 /* Ensure pending cp14 accesses complete before setting pwrdwn */ 65 mb(); 66 isb(); 67 etmcr = etm_readl(drvdata, ETMCR); 68 etmcr |= ETMCR_PWD_DWN; 69 etm_writel(drvdata, etmcr, ETMCR); 70 } 71 72 static void etm_clr_pwrdwn(struct etm_drvdata *drvdata) 73 { 74 u32 etmcr; 75 76 etmcr = etm_readl(drvdata, ETMCR); 77 etmcr &= ~ETMCR_PWD_DWN; 78 etm_writel(drvdata, etmcr, ETMCR); 79 /* Ensure pwrup completes before subsequent cp14 accesses */ 80 mb(); 81 isb(); 82 } 83 84 static void etm_set_pwrup(struct etm_drvdata *drvdata) 85 { 86 u32 etmpdcr; 87 88 etmpdcr = readl_relaxed(drvdata->base + ETMPDCR); 89 etmpdcr |= ETMPDCR_PWD_UP; 90 writel_relaxed(etmpdcr, drvdata->base + ETMPDCR); 91 /* Ensure pwrup completes before subsequent cp14 accesses */ 92 mb(); 93 isb(); 94 } 95 96 static void etm_clr_pwrup(struct etm_drvdata *drvdata) 97 { 98 u32 etmpdcr; 99 100 /* Ensure pending cp14 accesses complete before clearing pwrup */ 101 mb(); 102 isb(); 103 etmpdcr = readl_relaxed(drvdata->base + ETMPDCR); 104 etmpdcr &= ~ETMPDCR_PWD_UP; 105 writel_relaxed(etmpdcr, drvdata->base + ETMPDCR); 106 } 107 108 /** 109 * coresight_timeout_etm - loop until a bit has changed to a specific state. 110 * @drvdata: etm's private data structure. 111 * @offset: address of a register, starting from @addr. 112 * @position: the position of the bit of interest. 113 * @value: the value the bit should have. 114 * 115 * Basically the same as @coresight_timeout except for the register access 116 * method where we have to account for CP14 configurations. 117 118 * Return: 0 as soon as the bit has taken the desired state or -EAGAIN if 119 * TIMEOUT_US has elapsed, which ever happens first. 120 */ 121 122 static int coresight_timeout_etm(struct etm_drvdata *drvdata, u32 offset, 123 int position, int value) 124 { 125 int i; 126 u32 val; 127 128 for (i = TIMEOUT_US; i > 0; i--) { 129 val = etm_readl(drvdata, offset); 130 /* Waiting on the bit to go from 0 to 1 */ 131 if (value) { 132 if (val & BIT(position)) 133 return 0; 134 /* Waiting on the bit to go from 1 to 0 */ 135 } else { 136 if (!(val & BIT(position))) 137 return 0; 138 } 139 140 /* 141 * Delay is arbitrary - the specification doesn't say how long 142 * we are expected to wait. Extra check required to make sure 143 * we don't wait needlessly on the last iteration. 144 */ 145 if (i - 1) 146 udelay(1); 147 } 148 149 return -EAGAIN; 150 } 151 152 153 static void etm_set_prog(struct etm_drvdata *drvdata) 154 { 155 u32 etmcr; 156 157 etmcr = etm_readl(drvdata, ETMCR); 158 etmcr |= ETMCR_ETM_PRG; 159 etm_writel(drvdata, etmcr, ETMCR); 160 /* 161 * Recommended by spec for cp14 accesses to ensure etmcr write is 162 * complete before polling etmsr 163 */ 164 isb(); 165 if (coresight_timeout_etm(drvdata, ETMSR, ETMSR_PROG_BIT, 1)) { 166 dev_err(&drvdata->csdev->dev, 167 "%s: timeout observed when probing at offset %#x\n", 168 __func__, ETMSR); 169 } 170 } 171 172 static void etm_clr_prog(struct etm_drvdata *drvdata) 173 { 174 u32 etmcr; 175 176 etmcr = etm_readl(drvdata, ETMCR); 177 etmcr &= ~ETMCR_ETM_PRG; 178 etm_writel(drvdata, etmcr, ETMCR); 179 /* 180 * Recommended by spec for cp14 accesses to ensure etmcr write is 181 * complete before polling etmsr 182 */ 183 isb(); 184 if (coresight_timeout_etm(drvdata, ETMSR, ETMSR_PROG_BIT, 0)) { 185 dev_err(&drvdata->csdev->dev, 186 "%s: timeout observed when probing at offset %#x\n", 187 __func__, ETMSR); 188 } 189 } 190 191 void etm_set_default(struct etm_config *config) 192 { 193 int i; 194 195 if (WARN_ON_ONCE(!config)) 196 return; 197 198 /* 199 * Taken verbatim from the TRM: 200 * 201 * To trace all memory: 202 * set bit [24] in register 0x009, the ETMTECR1, to 1 203 * set all other bits in register 0x009, the ETMTECR1, to 0 204 * set all bits in register 0x007, the ETMTECR2, to 0 205 * set register 0x008, the ETMTEEVR, to 0x6F (TRUE). 206 */ 207 config->enable_ctrl1 = ETMTECR1_INC_EXC; 208 config->enable_ctrl2 = 0x0; 209 config->enable_event = ETM_HARD_WIRE_RES_A; 210 211 config->trigger_event = ETM_DEFAULT_EVENT_VAL; 212 config->enable_event = ETM_HARD_WIRE_RES_A; 213 214 config->seq_12_event = ETM_DEFAULT_EVENT_VAL; 215 config->seq_21_event = ETM_DEFAULT_EVENT_VAL; 216 config->seq_23_event = ETM_DEFAULT_EVENT_VAL; 217 config->seq_31_event = ETM_DEFAULT_EVENT_VAL; 218 config->seq_32_event = ETM_DEFAULT_EVENT_VAL; 219 config->seq_13_event = ETM_DEFAULT_EVENT_VAL; 220 config->timestamp_event = ETM_DEFAULT_EVENT_VAL; 221 222 for (i = 0; i < ETM_MAX_CNTR; i++) { 223 config->cntr_rld_val[i] = 0x0; 224 config->cntr_event[i] = ETM_DEFAULT_EVENT_VAL; 225 config->cntr_rld_event[i] = ETM_DEFAULT_EVENT_VAL; 226 config->cntr_val[i] = 0x0; 227 } 228 229 config->seq_curr_state = 0x0; 230 config->ctxid_idx = 0x0; 231 for (i = 0; i < ETM_MAX_CTXID_CMP; i++) 232 config->ctxid_pid[i] = 0x0; 233 234 config->ctxid_mask = 0x0; 235 /* Setting default to 1024 as per TRM recommendation */ 236 config->sync_freq = 0x400; 237 } 238 239 void etm_config_trace_mode(struct etm_config *config) 240 { 241 u32 flags, mode; 242 243 mode = config->mode; 244 245 mode &= (ETM_MODE_EXCL_KERN | ETM_MODE_EXCL_USER); 246 247 /* excluding kernel AND user space doesn't make sense */ 248 if (mode == (ETM_MODE_EXCL_KERN | ETM_MODE_EXCL_USER)) 249 return; 250 251 /* nothing to do if neither flags are set */ 252 if (!(mode & ETM_MODE_EXCL_KERN) && !(mode & ETM_MODE_EXCL_USER)) 253 return; 254 255 flags = (1 << 0 | /* instruction execute */ 256 3 << 3 | /* ARM instruction */ 257 0 << 5 | /* No data value comparison */ 258 0 << 7 | /* No exact mach */ 259 0 << 8); /* Ignore context ID */ 260 261 /* No need to worry about single address comparators. */ 262 config->enable_ctrl2 = 0x0; 263 264 /* Bit 0 is address range comparator 1 */ 265 config->enable_ctrl1 = ETMTECR1_ADDR_COMP_1; 266 267 /* 268 * On ETMv3.5: 269 * ETMACTRn[13,11] == Non-secure state comparison control 270 * ETMACTRn[12,10] == Secure state comparison control 271 * 272 * b00 == Match in all modes in this state 273 * b01 == Do not match in any more in this state 274 * b10 == Match in all modes excepts user mode in this state 275 * b11 == Match only in user mode in this state 276 */ 277 278 /* Tracing in secure mode is not supported at this time */ 279 flags |= (0 << 12 | 1 << 10); 280 281 if (mode & ETM_MODE_EXCL_USER) { 282 /* exclude user, match all modes except user mode */ 283 flags |= (1 << 13 | 0 << 11); 284 } else { 285 /* exclude kernel, match only in user mode */ 286 flags |= (1 << 13 | 1 << 11); 287 } 288 289 /* 290 * The ETMEEVR register is already set to "hard wire A". As such 291 * all there is to do is setup an address comparator that spans 292 * the entire address range and configure the state and mode bits. 293 */ 294 config->addr_val[0] = (u32) 0x0; 295 config->addr_val[1] = (u32) ~0x0; 296 config->addr_acctype[0] = flags; 297 config->addr_acctype[1] = flags; 298 config->addr_type[0] = ETM_ADDR_TYPE_RANGE; 299 config->addr_type[1] = ETM_ADDR_TYPE_RANGE; 300 } 301 302 #define ETM3X_SUPPORTED_OPTIONS (ETMCR_CYC_ACC | \ 303 ETMCR_TIMESTAMP_EN | \ 304 ETMCR_RETURN_STACK) 305 306 static int etm_parse_event_config(struct etm_drvdata *drvdata, 307 struct perf_event *event) 308 { 309 struct etm_config *config = &drvdata->config; 310 struct perf_event_attr *attr = &event->attr; 311 312 if (!attr) 313 return -EINVAL; 314 315 /* Clear configuration from previous run */ 316 memset(config, 0, sizeof(struct etm_config)); 317 318 if (attr->exclude_kernel) 319 config->mode = ETM_MODE_EXCL_KERN; 320 321 if (attr->exclude_user) 322 config->mode = ETM_MODE_EXCL_USER; 323 324 /* Always start from the default config */ 325 etm_set_default(config); 326 327 /* 328 * By default the tracers are configured to trace the whole address 329 * range. Narrow the field only if requested by user space. 330 */ 331 if (config->mode) 332 etm_config_trace_mode(config); 333 334 /* 335 * At this time only cycle accurate, return stack and timestamp 336 * options are available. 337 */ 338 if (attr->config & ~ETM3X_SUPPORTED_OPTIONS) 339 return -EINVAL; 340 341 config->ctrl = attr->config; 342 343 /* Don't trace contextID when runs in non-root PID namespace */ 344 if (!task_is_in_init_pid_ns(current)) 345 config->ctrl &= ~ETMCR_CTXID_SIZE; 346 347 /* 348 * Possible to have cores with PTM (supports ret stack) and ETM 349 * (never has ret stack) on the same SoC. So if we have a request 350 * for return stack that can't be honoured on this core then 351 * clear the bit - trace will still continue normally 352 */ 353 if ((config->ctrl & ETMCR_RETURN_STACK) && 354 !(drvdata->etmccer & ETMCCER_RETSTACK)) 355 config->ctrl &= ~ETMCR_RETURN_STACK; 356 357 return 0; 358 } 359 360 static int etm_enable_hw(struct etm_drvdata *drvdata) 361 { 362 int i, rc; 363 u32 etmcr; 364 struct etm_config *config = &drvdata->config; 365 struct coresight_device *csdev = drvdata->csdev; 366 367 CS_UNLOCK(drvdata->base); 368 369 rc = coresight_claim_device_unlocked(csdev); 370 if (rc) 371 goto done; 372 373 /* Turn engine on */ 374 etm_clr_pwrdwn(drvdata); 375 /* Apply power to trace registers */ 376 etm_set_pwrup(drvdata); 377 /* Make sure all registers are accessible */ 378 etm_os_unlock(drvdata); 379 380 etm_set_prog(drvdata); 381 382 etmcr = etm_readl(drvdata, ETMCR); 383 /* Clear setting from a previous run if need be */ 384 etmcr &= ~ETM3X_SUPPORTED_OPTIONS; 385 etmcr |= drvdata->port_size; 386 etmcr |= ETMCR_ETM_EN; 387 etm_writel(drvdata, config->ctrl | etmcr, ETMCR); 388 etm_writel(drvdata, config->trigger_event, ETMTRIGGER); 389 etm_writel(drvdata, config->startstop_ctrl, ETMTSSCR); 390 etm_writel(drvdata, config->enable_event, ETMTEEVR); 391 etm_writel(drvdata, config->enable_ctrl1, ETMTECR1); 392 etm_writel(drvdata, config->fifofull_level, ETMFFLR); 393 for (i = 0; i < drvdata->nr_addr_cmp; i++) { 394 etm_writel(drvdata, config->addr_val[i], ETMACVRn(i)); 395 etm_writel(drvdata, config->addr_acctype[i], ETMACTRn(i)); 396 } 397 for (i = 0; i < drvdata->nr_cntr; i++) { 398 etm_writel(drvdata, config->cntr_rld_val[i], ETMCNTRLDVRn(i)); 399 etm_writel(drvdata, config->cntr_event[i], ETMCNTENRn(i)); 400 etm_writel(drvdata, config->cntr_rld_event[i], 401 ETMCNTRLDEVRn(i)); 402 etm_writel(drvdata, config->cntr_val[i], ETMCNTVRn(i)); 403 } 404 etm_writel(drvdata, config->seq_12_event, ETMSQ12EVR); 405 etm_writel(drvdata, config->seq_21_event, ETMSQ21EVR); 406 etm_writel(drvdata, config->seq_23_event, ETMSQ23EVR); 407 etm_writel(drvdata, config->seq_31_event, ETMSQ31EVR); 408 etm_writel(drvdata, config->seq_32_event, ETMSQ32EVR); 409 etm_writel(drvdata, config->seq_13_event, ETMSQ13EVR); 410 etm_writel(drvdata, config->seq_curr_state, ETMSQR); 411 for (i = 0; i < drvdata->nr_ext_out; i++) 412 etm_writel(drvdata, ETM_DEFAULT_EVENT_VAL, ETMEXTOUTEVRn(i)); 413 for (i = 0; i < drvdata->nr_ctxid_cmp; i++) 414 etm_writel(drvdata, config->ctxid_pid[i], ETMCIDCVRn(i)); 415 etm_writel(drvdata, config->ctxid_mask, ETMCIDCMR); 416 etm_writel(drvdata, config->sync_freq, ETMSYNCFR); 417 /* No external input selected */ 418 etm_writel(drvdata, 0x0, ETMEXTINSELR); 419 etm_writel(drvdata, config->timestamp_event, ETMTSEVR); 420 /* No auxiliary control selected */ 421 etm_writel(drvdata, 0x0, ETMAUXCR); 422 etm_writel(drvdata, drvdata->traceid, ETMTRACEIDR); 423 /* No VMID comparator value selected */ 424 etm_writel(drvdata, 0x0, ETMVMIDCVR); 425 426 etm_clr_prog(drvdata); 427 428 done: 429 CS_LOCK(drvdata->base); 430 431 dev_dbg(&drvdata->csdev->dev, "cpu: %d enable smp call done: %d\n", 432 drvdata->cpu, rc); 433 return rc; 434 } 435 436 struct etm_enable_arg { 437 struct etm_drvdata *drvdata; 438 int rc; 439 }; 440 441 static void etm_enable_hw_smp_call(void *info) 442 { 443 struct etm_enable_arg *arg = info; 444 445 if (WARN_ON(!arg)) 446 return; 447 arg->rc = etm_enable_hw(arg->drvdata); 448 } 449 450 static int etm_cpu_id(struct coresight_device *csdev) 451 { 452 struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); 453 454 return drvdata->cpu; 455 } 456 457 int etm_get_trace_id(struct etm_drvdata *drvdata) 458 { 459 unsigned long flags; 460 int trace_id = -1; 461 struct device *etm_dev; 462 463 if (!drvdata) 464 goto out; 465 466 etm_dev = drvdata->csdev->dev.parent; 467 if (!local_read(&drvdata->mode)) 468 return drvdata->traceid; 469 470 pm_runtime_get_sync(etm_dev); 471 472 spin_lock_irqsave(&drvdata->spinlock, flags); 473 474 CS_UNLOCK(drvdata->base); 475 trace_id = (etm_readl(drvdata, ETMTRACEIDR) & ETM_TRACEID_MASK); 476 CS_LOCK(drvdata->base); 477 478 spin_unlock_irqrestore(&drvdata->spinlock, flags); 479 pm_runtime_put(etm_dev); 480 481 out: 482 return trace_id; 483 484 } 485 486 static int etm_trace_id(struct coresight_device *csdev) 487 { 488 struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); 489 490 return etm_get_trace_id(drvdata); 491 } 492 493 static int etm_enable_perf(struct coresight_device *csdev, 494 struct perf_event *event) 495 { 496 struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); 497 498 if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id())) 499 return -EINVAL; 500 501 /* Configure the tracer based on the session's specifics */ 502 etm_parse_event_config(drvdata, event); 503 /* And enable it */ 504 return etm_enable_hw(drvdata); 505 } 506 507 static int etm_enable_sysfs(struct coresight_device *csdev) 508 { 509 struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); 510 struct etm_enable_arg arg = { }; 511 int ret; 512 513 spin_lock(&drvdata->spinlock); 514 515 /* 516 * Configure the ETM only if the CPU is online. If it isn't online 517 * hw configuration will take place on the local CPU during bring up. 518 */ 519 if (cpu_online(drvdata->cpu)) { 520 arg.drvdata = drvdata; 521 ret = smp_call_function_single(drvdata->cpu, 522 etm_enable_hw_smp_call, &arg, 1); 523 if (!ret) 524 ret = arg.rc; 525 if (!ret) 526 drvdata->sticky_enable = true; 527 } else { 528 ret = -ENODEV; 529 } 530 531 spin_unlock(&drvdata->spinlock); 532 533 if (!ret) 534 dev_dbg(&csdev->dev, "ETM tracing enabled\n"); 535 return ret; 536 } 537 538 static int etm_enable(struct coresight_device *csdev, 539 struct perf_event *event, u32 mode) 540 { 541 int ret; 542 u32 val; 543 struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); 544 545 val = local_cmpxchg(&drvdata->mode, CS_MODE_DISABLED, mode); 546 547 /* Someone is already using the tracer */ 548 if (val) 549 return -EBUSY; 550 551 switch (mode) { 552 case CS_MODE_SYSFS: 553 ret = etm_enable_sysfs(csdev); 554 break; 555 case CS_MODE_PERF: 556 ret = etm_enable_perf(csdev, event); 557 break; 558 default: 559 ret = -EINVAL; 560 } 561 562 /* The tracer didn't start */ 563 if (ret) 564 local_set(&drvdata->mode, CS_MODE_DISABLED); 565 566 return ret; 567 } 568 569 static void etm_disable_hw(void *info) 570 { 571 int i; 572 struct etm_drvdata *drvdata = info; 573 struct etm_config *config = &drvdata->config; 574 struct coresight_device *csdev = drvdata->csdev; 575 576 CS_UNLOCK(drvdata->base); 577 etm_set_prog(drvdata); 578 579 /* Read back sequencer and counters for post trace analysis */ 580 config->seq_curr_state = (etm_readl(drvdata, ETMSQR) & ETM_SQR_MASK); 581 582 for (i = 0; i < drvdata->nr_cntr; i++) 583 config->cntr_val[i] = etm_readl(drvdata, ETMCNTVRn(i)); 584 585 etm_set_pwrdwn(drvdata); 586 coresight_disclaim_device_unlocked(csdev); 587 588 CS_LOCK(drvdata->base); 589 590 dev_dbg(&drvdata->csdev->dev, 591 "cpu: %d disable smp call done\n", drvdata->cpu); 592 } 593 594 static void etm_disable_perf(struct coresight_device *csdev) 595 { 596 struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); 597 598 if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id())) 599 return; 600 601 CS_UNLOCK(drvdata->base); 602 603 /* Setting the prog bit disables tracing immediately */ 604 etm_set_prog(drvdata); 605 606 /* 607 * There is no way to know when the tracer will be used again so 608 * power down the tracer. 609 */ 610 etm_set_pwrdwn(drvdata); 611 coresight_disclaim_device_unlocked(csdev); 612 613 CS_LOCK(drvdata->base); 614 } 615 616 static void etm_disable_sysfs(struct coresight_device *csdev) 617 { 618 struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); 619 620 /* 621 * Taking hotplug lock here protects from clocks getting disabled 622 * with tracing being left on (crash scenario) if user disable occurs 623 * after cpu online mask indicates the cpu is offline but before the 624 * DYING hotplug callback is serviced by the ETM driver. 625 */ 626 cpus_read_lock(); 627 spin_lock(&drvdata->spinlock); 628 629 /* 630 * Executing etm_disable_hw on the cpu whose ETM is being disabled 631 * ensures that register writes occur when cpu is powered. 632 */ 633 smp_call_function_single(drvdata->cpu, etm_disable_hw, drvdata, 1); 634 635 spin_unlock(&drvdata->spinlock); 636 cpus_read_unlock(); 637 638 dev_dbg(&csdev->dev, "ETM tracing disabled\n"); 639 } 640 641 static void etm_disable(struct coresight_device *csdev, 642 struct perf_event *event) 643 { 644 u32 mode; 645 struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); 646 647 /* 648 * For as long as the tracer isn't disabled another entity can't 649 * change its status. As such we can read the status here without 650 * fearing it will change under us. 651 */ 652 mode = local_read(&drvdata->mode); 653 654 switch (mode) { 655 case CS_MODE_DISABLED: 656 break; 657 case CS_MODE_SYSFS: 658 etm_disable_sysfs(csdev); 659 break; 660 case CS_MODE_PERF: 661 etm_disable_perf(csdev); 662 break; 663 default: 664 WARN_ON_ONCE(mode); 665 return; 666 } 667 668 if (mode) 669 local_set(&drvdata->mode, CS_MODE_DISABLED); 670 } 671 672 static const struct coresight_ops_source etm_source_ops = { 673 .cpu_id = etm_cpu_id, 674 .trace_id = etm_trace_id, 675 .enable = etm_enable, 676 .disable = etm_disable, 677 }; 678 679 static const struct coresight_ops etm_cs_ops = { 680 .source_ops = &etm_source_ops, 681 }; 682 683 static int etm_online_cpu(unsigned int cpu) 684 { 685 if (!etmdrvdata[cpu]) 686 return 0; 687 688 if (etmdrvdata[cpu]->boot_enable && !etmdrvdata[cpu]->sticky_enable) 689 coresight_enable(etmdrvdata[cpu]->csdev); 690 return 0; 691 } 692 693 static int etm_starting_cpu(unsigned int cpu) 694 { 695 if (!etmdrvdata[cpu]) 696 return 0; 697 698 spin_lock(&etmdrvdata[cpu]->spinlock); 699 if (!etmdrvdata[cpu]->os_unlock) { 700 etm_os_unlock(etmdrvdata[cpu]); 701 etmdrvdata[cpu]->os_unlock = true; 702 } 703 704 if (local_read(&etmdrvdata[cpu]->mode)) 705 etm_enable_hw(etmdrvdata[cpu]); 706 spin_unlock(&etmdrvdata[cpu]->spinlock); 707 return 0; 708 } 709 710 static int etm_dying_cpu(unsigned int cpu) 711 { 712 if (!etmdrvdata[cpu]) 713 return 0; 714 715 spin_lock(&etmdrvdata[cpu]->spinlock); 716 if (local_read(&etmdrvdata[cpu]->mode)) 717 etm_disable_hw(etmdrvdata[cpu]); 718 spin_unlock(&etmdrvdata[cpu]->spinlock); 719 return 0; 720 } 721 722 static bool etm_arch_supported(u8 arch) 723 { 724 switch (arch) { 725 case ETM_ARCH_V3_3: 726 break; 727 case ETM_ARCH_V3_5: 728 break; 729 case PFT_ARCH_V1_0: 730 break; 731 case PFT_ARCH_V1_1: 732 break; 733 default: 734 return false; 735 } 736 return true; 737 } 738 739 static void etm_init_arch_data(void *info) 740 { 741 u32 etmidr; 742 u32 etmccr; 743 struct etm_drvdata *drvdata = info; 744 745 /* Make sure all registers are accessible */ 746 etm_os_unlock(drvdata); 747 748 CS_UNLOCK(drvdata->base); 749 750 /* First dummy read */ 751 (void)etm_readl(drvdata, ETMPDSR); 752 /* Provide power to ETM: ETMPDCR[3] == 1 */ 753 etm_set_pwrup(drvdata); 754 /* 755 * Clear power down bit since when this bit is set writes to 756 * certain registers might be ignored. 757 */ 758 etm_clr_pwrdwn(drvdata); 759 /* 760 * Set prog bit. It will be set from reset but this is included to 761 * ensure it is set 762 */ 763 etm_set_prog(drvdata); 764 765 /* Find all capabilities */ 766 etmidr = etm_readl(drvdata, ETMIDR); 767 drvdata->arch = BMVAL(etmidr, 4, 11); 768 drvdata->port_size = etm_readl(drvdata, ETMCR) & PORT_SIZE_MASK; 769 770 drvdata->etmccer = etm_readl(drvdata, ETMCCER); 771 etmccr = etm_readl(drvdata, ETMCCR); 772 drvdata->etmccr = etmccr; 773 drvdata->nr_addr_cmp = BMVAL(etmccr, 0, 3) * 2; 774 drvdata->nr_cntr = BMVAL(etmccr, 13, 15); 775 drvdata->nr_ext_inp = BMVAL(etmccr, 17, 19); 776 drvdata->nr_ext_out = BMVAL(etmccr, 20, 22); 777 drvdata->nr_ctxid_cmp = BMVAL(etmccr, 24, 25); 778 779 etm_set_pwrdwn(drvdata); 780 etm_clr_pwrup(drvdata); 781 CS_LOCK(drvdata->base); 782 } 783 784 static void etm_init_trace_id(struct etm_drvdata *drvdata) 785 { 786 drvdata->traceid = coresight_get_trace_id(drvdata->cpu); 787 } 788 789 static int __init etm_hp_setup(void) 790 { 791 int ret; 792 793 ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ARM_CORESIGHT_STARTING, 794 "arm/coresight:starting", 795 etm_starting_cpu, etm_dying_cpu); 796 797 if (ret) 798 return ret; 799 800 ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, 801 "arm/coresight:online", 802 etm_online_cpu, NULL); 803 804 /* HP dyn state ID returned in ret on success */ 805 if (ret > 0) { 806 hp_online = ret; 807 return 0; 808 } 809 810 /* failed dyn state - remove others */ 811 cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING); 812 813 return ret; 814 } 815 816 static void etm_hp_clear(void) 817 { 818 cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING); 819 if (hp_online) { 820 cpuhp_remove_state_nocalls(hp_online); 821 hp_online = 0; 822 } 823 } 824 825 static int etm_probe(struct amba_device *adev, const struct amba_id *id) 826 { 827 int ret; 828 void __iomem *base; 829 struct device *dev = &adev->dev; 830 struct coresight_platform_data *pdata = NULL; 831 struct etm_drvdata *drvdata; 832 struct resource *res = &adev->res; 833 struct coresight_desc desc = { 0 }; 834 835 drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL); 836 if (!drvdata) 837 return -ENOMEM; 838 839 drvdata->use_cp14 = fwnode_property_read_bool(dev->fwnode, "arm,cp14"); 840 dev_set_drvdata(dev, drvdata); 841 842 /* Validity for the resource is already checked by the AMBA core */ 843 base = devm_ioremap_resource(dev, res); 844 if (IS_ERR(base)) 845 return PTR_ERR(base); 846 847 drvdata->base = base; 848 desc.access = CSDEV_ACCESS_IOMEM(base); 849 850 spin_lock_init(&drvdata->spinlock); 851 852 drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */ 853 if (!IS_ERR(drvdata->atclk)) { 854 ret = clk_prepare_enable(drvdata->atclk); 855 if (ret) 856 return ret; 857 } 858 859 drvdata->cpu = coresight_get_cpu(dev); 860 if (drvdata->cpu < 0) 861 return drvdata->cpu; 862 863 desc.name = devm_kasprintf(dev, GFP_KERNEL, "etm%d", drvdata->cpu); 864 if (!desc.name) 865 return -ENOMEM; 866 867 if (smp_call_function_single(drvdata->cpu, 868 etm_init_arch_data, drvdata, 1)) 869 dev_err(dev, "ETM arch init failed\n"); 870 871 if (etm_arch_supported(drvdata->arch) == false) 872 return -EINVAL; 873 874 etm_init_trace_id(drvdata); 875 etm_set_default(&drvdata->config); 876 877 pdata = coresight_get_platform_data(dev); 878 if (IS_ERR(pdata)) 879 return PTR_ERR(pdata); 880 881 adev->dev.platform_data = pdata; 882 883 desc.type = CORESIGHT_DEV_TYPE_SOURCE; 884 desc.subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_PROC; 885 desc.ops = &etm_cs_ops; 886 desc.pdata = pdata; 887 desc.dev = dev; 888 desc.groups = coresight_etm_groups; 889 drvdata->csdev = coresight_register(&desc); 890 if (IS_ERR(drvdata->csdev)) 891 return PTR_ERR(drvdata->csdev); 892 893 ret = etm_perf_symlink(drvdata->csdev, true); 894 if (ret) { 895 coresight_unregister(drvdata->csdev); 896 return ret; 897 } 898 899 etmdrvdata[drvdata->cpu] = drvdata; 900 901 pm_runtime_put(&adev->dev); 902 dev_info(&drvdata->csdev->dev, 903 "%s initialized\n", (char *)coresight_get_uci_data(id)); 904 if (boot_enable) { 905 coresight_enable(drvdata->csdev); 906 drvdata->boot_enable = true; 907 } 908 909 return 0; 910 } 911 912 static void clear_etmdrvdata(void *info) 913 { 914 int cpu = *(int *)info; 915 916 etmdrvdata[cpu] = NULL; 917 } 918 919 static void etm_remove(struct amba_device *adev) 920 { 921 struct etm_drvdata *drvdata = dev_get_drvdata(&adev->dev); 922 923 etm_perf_symlink(drvdata->csdev, false); 924 925 /* 926 * Taking hotplug lock here to avoid racing between etm_remove and 927 * CPU hotplug call backs. 928 */ 929 cpus_read_lock(); 930 /* 931 * The readers for etmdrvdata[] are CPU hotplug call backs 932 * and PM notification call backs. Change etmdrvdata[i] on 933 * CPU i ensures these call backs has consistent view 934 * inside one call back function. 935 */ 936 if (smp_call_function_single(drvdata->cpu, clear_etmdrvdata, &drvdata->cpu, 1)) 937 etmdrvdata[drvdata->cpu] = NULL; 938 939 cpus_read_unlock(); 940 941 coresight_unregister(drvdata->csdev); 942 } 943 944 #ifdef CONFIG_PM 945 static int etm_runtime_suspend(struct device *dev) 946 { 947 struct etm_drvdata *drvdata = dev_get_drvdata(dev); 948 949 if (drvdata && !IS_ERR(drvdata->atclk)) 950 clk_disable_unprepare(drvdata->atclk); 951 952 return 0; 953 } 954 955 static int etm_runtime_resume(struct device *dev) 956 { 957 struct etm_drvdata *drvdata = dev_get_drvdata(dev); 958 959 if (drvdata && !IS_ERR(drvdata->atclk)) 960 clk_prepare_enable(drvdata->atclk); 961 962 return 0; 963 } 964 #endif 965 966 static const struct dev_pm_ops etm_dev_pm_ops = { 967 SET_RUNTIME_PM_OPS(etm_runtime_suspend, etm_runtime_resume, NULL) 968 }; 969 970 static const struct amba_id etm_ids[] = { 971 /* ETM 3.3 */ 972 CS_AMBA_ID_DATA(0x000bb921, "ETM 3.3"), 973 /* ETM 3.5 - Cortex-A5 */ 974 CS_AMBA_ID_DATA(0x000bb955, "ETM 3.5"), 975 /* ETM 3.5 */ 976 CS_AMBA_ID_DATA(0x000bb956, "ETM 3.5"), 977 /* PTM 1.0 */ 978 CS_AMBA_ID_DATA(0x000bb950, "PTM 1.0"), 979 /* PTM 1.1 */ 980 CS_AMBA_ID_DATA(0x000bb95f, "PTM 1.1"), 981 /* PTM 1.1 Qualcomm */ 982 CS_AMBA_ID_DATA(0x000b006f, "PTM 1.1"), 983 { 0, 0}, 984 }; 985 986 MODULE_DEVICE_TABLE(amba, etm_ids); 987 988 static struct amba_driver etm_driver = { 989 .drv = { 990 .name = "coresight-etm3x", 991 .owner = THIS_MODULE, 992 .pm = &etm_dev_pm_ops, 993 .suppress_bind_attrs = true, 994 }, 995 .probe = etm_probe, 996 .remove = etm_remove, 997 .id_table = etm_ids, 998 }; 999 1000 static int __init etm_init(void) 1001 { 1002 int ret; 1003 1004 ret = etm_hp_setup(); 1005 1006 /* etm_hp_setup() does its own cleanup - exit on error */ 1007 if (ret) 1008 return ret; 1009 1010 ret = amba_driver_register(&etm_driver); 1011 if (ret) { 1012 pr_err("Error registering etm3x driver\n"); 1013 etm_hp_clear(); 1014 } 1015 1016 return ret; 1017 } 1018 1019 static void __exit etm_exit(void) 1020 { 1021 amba_driver_unregister(&etm_driver); 1022 etm_hp_clear(); 1023 } 1024 1025 module_init(etm_init); 1026 module_exit(etm_exit); 1027 1028 MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>"); 1029 MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@linaro.org>"); 1030 MODULE_DESCRIPTION("Arm CoreSight Program Flow Trace driver"); 1031 MODULE_LICENSE("GPL v2"); 1032