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