xref: /linux/drivers/hwtracing/coresight/coresight-etm4x-core.c (revision 4359a011e259a4608afc7fb3635370c9d4ba5943)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2014, The Linux Foundation. All rights reserved.
4  */
5 
6 #include <linux/bitops.h>
7 #include <linux/kernel.h>
8 #include <linux/moduleparam.h>
9 #include <linux/init.h>
10 #include <linux/types.h>
11 #include <linux/device.h>
12 #include <linux/io.h>
13 #include <linux/err.h>
14 #include <linux/fs.h>
15 #include <linux/slab.h>
16 #include <linux/delay.h>
17 #include <linux/smp.h>
18 #include <linux/sysfs.h>
19 #include <linux/stat.h>
20 #include <linux/clk.h>
21 #include <linux/cpu.h>
22 #include <linux/cpu_pm.h>
23 #include <linux/coresight.h>
24 #include <linux/coresight-pmu.h>
25 #include <linux/pm_wakeup.h>
26 #include <linux/amba/bus.h>
27 #include <linux/seq_file.h>
28 #include <linux/uaccess.h>
29 #include <linux/perf_event.h>
30 #include <linux/platform_device.h>
31 #include <linux/pm_runtime.h>
32 #include <linux/property.h>
33 
34 #include <asm/barrier.h>
35 #include <asm/sections.h>
36 #include <asm/sysreg.h>
37 #include <asm/local.h>
38 #include <asm/virt.h>
39 
40 #include "coresight-etm4x.h"
41 #include "coresight-etm-perf.h"
42 #include "coresight-etm4x-cfg.h"
43 #include "coresight-self-hosted-trace.h"
44 #include "coresight-syscfg.h"
45 
46 static int boot_enable;
47 module_param(boot_enable, int, 0444);
48 MODULE_PARM_DESC(boot_enable, "Enable tracing on boot");
49 
50 #define PARAM_PM_SAVE_FIRMWARE	  0 /* save self-hosted state as per firmware */
51 #define PARAM_PM_SAVE_NEVER	  1 /* never save any state */
52 #define PARAM_PM_SAVE_SELF_HOSTED 2 /* save self-hosted state only */
53 
54 static int pm_save_enable = PARAM_PM_SAVE_FIRMWARE;
55 module_param(pm_save_enable, int, 0444);
56 MODULE_PARM_DESC(pm_save_enable,
57 	"Save/restore state on power down: 1 = never, 2 = self-hosted");
58 
59 static struct etmv4_drvdata *etmdrvdata[NR_CPUS];
60 static void etm4_set_default_config(struct etmv4_config *config);
61 static int etm4_set_event_filters(struct etmv4_drvdata *drvdata,
62 				  struct perf_event *event);
63 static u64 etm4_get_access_type(struct etmv4_config *config);
64 
65 static enum cpuhp_state hp_online;
66 
67 struct etm4_init_arg {
68 	unsigned int		pid;
69 	struct etmv4_drvdata	*drvdata;
70 	struct csdev_access	*csa;
71 };
72 
73 /*
74  * Check if TRCSSPCICRn(i) is implemented for a given instance.
75  *
76  * TRCSSPCICRn is implemented only if :
77  *	TRCSSPCICR<n> is present only if all of the following are true:
78  *		TRCIDR4.NUMSSCC > n.
79  *		TRCIDR4.NUMPC > 0b0000 .
80  *		TRCSSCSR<n>.PC == 0b1
81  */
82 static inline bool etm4x_sspcicrn_present(struct etmv4_drvdata *drvdata, int n)
83 {
84 	return (n < drvdata->nr_ss_cmp) &&
85 	       drvdata->nr_pe &&
86 	       (drvdata->config.ss_status[n] & TRCSSCSRn_PC);
87 }
88 
89 u64 etm4x_sysreg_read(u32 offset, bool _relaxed, bool _64bit)
90 {
91 	u64 res = 0;
92 
93 	switch (offset) {
94 	ETM4x_READ_SYSREG_CASES(res)
95 	default :
96 		pr_warn_ratelimited("etm4x: trying to read unsupported register @%x\n",
97 			 offset);
98 	}
99 
100 	if (!_relaxed)
101 		__io_ar(res);	/* Imitate the !relaxed I/O helpers */
102 
103 	return res;
104 }
105 
106 void etm4x_sysreg_write(u64 val, u32 offset, bool _relaxed, bool _64bit)
107 {
108 	if (!_relaxed)
109 		__io_bw();	/* Imitate the !relaxed I/O helpers */
110 	if (!_64bit)
111 		val &= GENMASK(31, 0);
112 
113 	switch (offset) {
114 	ETM4x_WRITE_SYSREG_CASES(val)
115 	default :
116 		pr_warn_ratelimited("etm4x: trying to write to unsupported register @%x\n",
117 			offset);
118 	}
119 }
120 
121 static u64 ete_sysreg_read(u32 offset, bool _relaxed, bool _64bit)
122 {
123 	u64 res = 0;
124 
125 	switch (offset) {
126 	ETE_READ_CASES(res)
127 	default :
128 		pr_warn_ratelimited("ete: trying to read unsupported register @%x\n",
129 				    offset);
130 	}
131 
132 	if (!_relaxed)
133 		__io_ar(res);	/* Imitate the !relaxed I/O helpers */
134 
135 	return res;
136 }
137 
138 static void ete_sysreg_write(u64 val, u32 offset, bool _relaxed, bool _64bit)
139 {
140 	if (!_relaxed)
141 		__io_bw();	/* Imitate the !relaxed I/O helpers */
142 	if (!_64bit)
143 		val &= GENMASK(31, 0);
144 
145 	switch (offset) {
146 	ETE_WRITE_CASES(val)
147 	default :
148 		pr_warn_ratelimited("ete: trying to write to unsupported register @%x\n",
149 				    offset);
150 	}
151 }
152 
153 static void etm_detect_os_lock(struct etmv4_drvdata *drvdata,
154 			       struct csdev_access *csa)
155 {
156 	u32 oslsr = etm4x_relaxed_read32(csa, TRCOSLSR);
157 
158 	drvdata->os_lock_model = ETM_OSLSR_OSLM(oslsr);
159 }
160 
161 static void etm_write_os_lock(struct etmv4_drvdata *drvdata,
162 			      struct csdev_access *csa, u32 val)
163 {
164 	val = !!val;
165 
166 	switch (drvdata->os_lock_model) {
167 	case ETM_OSLOCK_PRESENT:
168 		etm4x_relaxed_write32(csa, val, TRCOSLAR);
169 		break;
170 	case ETM_OSLOCK_PE:
171 		write_sysreg_s(val, SYS_OSLAR_EL1);
172 		break;
173 	default:
174 		pr_warn_once("CPU%d: Unsupported Trace OSLock model: %x\n",
175 			     smp_processor_id(), drvdata->os_lock_model);
176 		fallthrough;
177 	case ETM_OSLOCK_NI:
178 		return;
179 	}
180 	isb();
181 }
182 
183 static inline void etm4_os_unlock_csa(struct etmv4_drvdata *drvdata,
184 				      struct csdev_access *csa)
185 {
186 	WARN_ON(drvdata->cpu != smp_processor_id());
187 
188 	/* Writing 0 to OS Lock unlocks the trace unit registers */
189 	etm_write_os_lock(drvdata, csa, 0x0);
190 	drvdata->os_unlock = true;
191 }
192 
193 static void etm4_os_unlock(struct etmv4_drvdata *drvdata)
194 {
195 	if (!WARN_ON(!drvdata->csdev))
196 		etm4_os_unlock_csa(drvdata, &drvdata->csdev->access);
197 }
198 
199 static void etm4_os_lock(struct etmv4_drvdata *drvdata)
200 {
201 	if (WARN_ON(!drvdata->csdev))
202 		return;
203 	/* Writing 0x1 to OS Lock locks the trace registers */
204 	etm_write_os_lock(drvdata, &drvdata->csdev->access, 0x1);
205 	drvdata->os_unlock = false;
206 }
207 
208 static void etm4_cs_lock(struct etmv4_drvdata *drvdata,
209 			 struct csdev_access *csa)
210 {
211 	/* Software Lock is only accessible via memory mapped interface */
212 	if (csa->io_mem)
213 		CS_LOCK(csa->base);
214 }
215 
216 static void etm4_cs_unlock(struct etmv4_drvdata *drvdata,
217 			   struct csdev_access *csa)
218 {
219 	if (csa->io_mem)
220 		CS_UNLOCK(csa->base);
221 }
222 
223 static int etm4_cpu_id(struct coresight_device *csdev)
224 {
225 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
226 
227 	return drvdata->cpu;
228 }
229 
230 static int etm4_trace_id(struct coresight_device *csdev)
231 {
232 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
233 
234 	return drvdata->trcid;
235 }
236 
237 struct etm4_enable_arg {
238 	struct etmv4_drvdata *drvdata;
239 	int rc;
240 };
241 
242 /*
243  * etm4x_prohibit_trace - Prohibit the CPU from tracing at all ELs.
244  * When the CPU supports FEAT_TRF, we could move the ETM to a trace
245  * prohibited state by filtering the Exception levels via TRFCR_EL1.
246  */
247 static void etm4x_prohibit_trace(struct etmv4_drvdata *drvdata)
248 {
249 	/* If the CPU doesn't support FEAT_TRF, nothing to do */
250 	if (!drvdata->trfcr)
251 		return;
252 	cpu_prohibit_trace();
253 }
254 
255 /*
256  * etm4x_allow_trace - Allow CPU tracing in the respective ELs,
257  * as configured by the drvdata->config.mode for the current
258  * session. Even though we have TRCVICTLR bits to filter the
259  * trace in the ELs, it doesn't prevent the ETM from generating
260  * a packet (e.g, TraceInfo) that might contain the addresses from
261  * the excluded levels. Thus we use the additional controls provided
262  * via the Trace Filtering controls (FEAT_TRF) to make sure no trace
263  * is generated for the excluded ELs.
264  */
265 static void etm4x_allow_trace(struct etmv4_drvdata *drvdata)
266 {
267 	u64 trfcr = drvdata->trfcr;
268 
269 	/* If the CPU doesn't support FEAT_TRF, nothing to do */
270 	if (!trfcr)
271 		return;
272 
273 	if (drvdata->config.mode & ETM_MODE_EXCL_KERN)
274 		trfcr &= ~TRFCR_ELx_ExTRE;
275 	if (drvdata->config.mode & ETM_MODE_EXCL_USER)
276 		trfcr &= ~TRFCR_ELx_E0TRE;
277 
278 	write_trfcr(trfcr);
279 }
280 
281 #ifdef CONFIG_ETM4X_IMPDEF_FEATURE
282 
283 #define HISI_HIP08_AMBA_ID		0x000b6d01
284 #define ETM4_AMBA_MASK			0xfffff
285 #define HISI_HIP08_CORE_COMMIT_MASK	0x3000
286 #define HISI_HIP08_CORE_COMMIT_SHIFT	12
287 #define HISI_HIP08_CORE_COMMIT_FULL	0b00
288 #define HISI_HIP08_CORE_COMMIT_LVL_1	0b01
289 #define HISI_HIP08_CORE_COMMIT_REG	sys_reg(3, 1, 15, 2, 5)
290 
291 struct etm4_arch_features {
292 	void (*arch_callback)(bool enable);
293 };
294 
295 static bool etm4_hisi_match_pid(unsigned int id)
296 {
297 	return (id & ETM4_AMBA_MASK) == HISI_HIP08_AMBA_ID;
298 }
299 
300 static void etm4_hisi_config_core_commit(bool enable)
301 {
302 	u8 commit = enable ? HISI_HIP08_CORE_COMMIT_LVL_1 :
303 		    HISI_HIP08_CORE_COMMIT_FULL;
304 	u64 val;
305 
306 	/*
307 	 * bit 12 and 13 of HISI_HIP08_CORE_COMMIT_REG are used together
308 	 * to set core-commit, 2'b00 means cpu is at full speed, 2'b01,
309 	 * 2'b10, 2'b11 mean reduce pipeline speed, and 2'b01 means level-1
310 	 * speed(minimun value). So bit 12 and 13 should be cleared together.
311 	 */
312 	val = read_sysreg_s(HISI_HIP08_CORE_COMMIT_REG);
313 	val &= ~HISI_HIP08_CORE_COMMIT_MASK;
314 	val |= commit << HISI_HIP08_CORE_COMMIT_SHIFT;
315 	write_sysreg_s(val, HISI_HIP08_CORE_COMMIT_REG);
316 }
317 
318 static struct etm4_arch_features etm4_features[] = {
319 	[ETM4_IMPDEF_HISI_CORE_COMMIT] = {
320 		.arch_callback = etm4_hisi_config_core_commit,
321 	},
322 	{},
323 };
324 
325 static void etm4_enable_arch_specific(struct etmv4_drvdata *drvdata)
326 {
327 	struct etm4_arch_features *ftr;
328 	int bit;
329 
330 	for_each_set_bit(bit, drvdata->arch_features, ETM4_IMPDEF_FEATURE_MAX) {
331 		ftr = &etm4_features[bit];
332 
333 		if (ftr->arch_callback)
334 			ftr->arch_callback(true);
335 	}
336 }
337 
338 static void etm4_disable_arch_specific(struct etmv4_drvdata *drvdata)
339 {
340 	struct etm4_arch_features *ftr;
341 	int bit;
342 
343 	for_each_set_bit(bit, drvdata->arch_features, ETM4_IMPDEF_FEATURE_MAX) {
344 		ftr = &etm4_features[bit];
345 
346 		if (ftr->arch_callback)
347 			ftr->arch_callback(false);
348 	}
349 }
350 
351 static void etm4_check_arch_features(struct etmv4_drvdata *drvdata,
352 				      unsigned int id)
353 {
354 	if (etm4_hisi_match_pid(id))
355 		set_bit(ETM4_IMPDEF_HISI_CORE_COMMIT, drvdata->arch_features);
356 }
357 #else
358 static void etm4_enable_arch_specific(struct etmv4_drvdata *drvdata)
359 {
360 }
361 
362 static void etm4_disable_arch_specific(struct etmv4_drvdata *drvdata)
363 {
364 }
365 
366 static void etm4_check_arch_features(struct etmv4_drvdata *drvdata,
367 				     unsigned int id)
368 {
369 }
370 #endif /* CONFIG_ETM4X_IMPDEF_FEATURE */
371 
372 static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
373 {
374 	int i, rc;
375 	struct etmv4_config *config = &drvdata->config;
376 	struct coresight_device *csdev = drvdata->csdev;
377 	struct device *etm_dev = &csdev->dev;
378 	struct csdev_access *csa = &csdev->access;
379 
380 
381 	etm4_cs_unlock(drvdata, csa);
382 	etm4_enable_arch_specific(drvdata);
383 
384 	etm4_os_unlock(drvdata);
385 
386 	rc = coresight_claim_device_unlocked(csdev);
387 	if (rc)
388 		goto done;
389 
390 	/* Disable the trace unit before programming trace registers */
391 	etm4x_relaxed_write32(csa, 0, TRCPRGCTLR);
392 
393 	/*
394 	 * If we use system instructions, we need to synchronize the
395 	 * write to the TRCPRGCTLR, before accessing the TRCSTATR.
396 	 * See ARM IHI0064F, section
397 	 * "4.3.7 Synchronization of register updates"
398 	 */
399 	if (!csa->io_mem)
400 		isb();
401 
402 	/* wait for TRCSTATR.IDLE to go up */
403 	if (coresight_timeout(csa, TRCSTATR, TRCSTATR_IDLE_BIT, 1))
404 		dev_err(etm_dev,
405 			"timeout while waiting for Idle Trace Status\n");
406 	if (drvdata->nr_pe)
407 		etm4x_relaxed_write32(csa, config->pe_sel, TRCPROCSELR);
408 	etm4x_relaxed_write32(csa, config->cfg, TRCCONFIGR);
409 	/* nothing specific implemented */
410 	etm4x_relaxed_write32(csa, 0x0, TRCAUXCTLR);
411 	etm4x_relaxed_write32(csa, config->eventctrl0, TRCEVENTCTL0R);
412 	etm4x_relaxed_write32(csa, config->eventctrl1, TRCEVENTCTL1R);
413 	if (drvdata->stallctl)
414 		etm4x_relaxed_write32(csa, config->stall_ctrl, TRCSTALLCTLR);
415 	etm4x_relaxed_write32(csa, config->ts_ctrl, TRCTSCTLR);
416 	etm4x_relaxed_write32(csa, config->syncfreq, TRCSYNCPR);
417 	etm4x_relaxed_write32(csa, config->ccctlr, TRCCCCTLR);
418 	etm4x_relaxed_write32(csa, config->bb_ctrl, TRCBBCTLR);
419 	etm4x_relaxed_write32(csa, drvdata->trcid, TRCTRACEIDR);
420 	etm4x_relaxed_write32(csa, config->vinst_ctrl, TRCVICTLR);
421 	etm4x_relaxed_write32(csa, config->viiectlr, TRCVIIECTLR);
422 	etm4x_relaxed_write32(csa, config->vissctlr, TRCVISSCTLR);
423 	if (drvdata->nr_pe_cmp)
424 		etm4x_relaxed_write32(csa, config->vipcssctlr, TRCVIPCSSCTLR);
425 	for (i = 0; i < drvdata->nrseqstate - 1; i++)
426 		etm4x_relaxed_write32(csa, config->seq_ctrl[i], TRCSEQEVRn(i));
427 	etm4x_relaxed_write32(csa, config->seq_rst, TRCSEQRSTEVR);
428 	etm4x_relaxed_write32(csa, config->seq_state, TRCSEQSTR);
429 	etm4x_relaxed_write32(csa, config->ext_inp, TRCEXTINSELR);
430 	for (i = 0; i < drvdata->nr_cntr; i++) {
431 		etm4x_relaxed_write32(csa, config->cntrldvr[i], TRCCNTRLDVRn(i));
432 		etm4x_relaxed_write32(csa, config->cntr_ctrl[i], TRCCNTCTLRn(i));
433 		etm4x_relaxed_write32(csa, config->cntr_val[i], TRCCNTVRn(i));
434 	}
435 
436 	/*
437 	 * Resource selector pair 0 is always implemented and reserved.  As
438 	 * such start at 2.
439 	 */
440 	for (i = 2; i < drvdata->nr_resource * 2; i++)
441 		etm4x_relaxed_write32(csa, config->res_ctrl[i], TRCRSCTLRn(i));
442 
443 	for (i = 0; i < drvdata->nr_ss_cmp; i++) {
444 		/* always clear status bit on restart if using single-shot */
445 		if (config->ss_ctrl[i] || config->ss_pe_cmp[i])
446 			config->ss_status[i] &= ~TRCSSCSRn_STATUS;
447 		etm4x_relaxed_write32(csa, config->ss_ctrl[i], TRCSSCCRn(i));
448 		etm4x_relaxed_write32(csa, config->ss_status[i], TRCSSCSRn(i));
449 		if (etm4x_sspcicrn_present(drvdata, i))
450 			etm4x_relaxed_write32(csa, config->ss_pe_cmp[i], TRCSSPCICRn(i));
451 	}
452 	for (i = 0; i < drvdata->nr_addr_cmp; i++) {
453 		etm4x_relaxed_write64(csa, config->addr_val[i], TRCACVRn(i));
454 		etm4x_relaxed_write64(csa, config->addr_acc[i], TRCACATRn(i));
455 	}
456 	for (i = 0; i < drvdata->numcidc; i++)
457 		etm4x_relaxed_write64(csa, config->ctxid_pid[i], TRCCIDCVRn(i));
458 	etm4x_relaxed_write32(csa, config->ctxid_mask0, TRCCIDCCTLR0);
459 	if (drvdata->numcidc > 4)
460 		etm4x_relaxed_write32(csa, config->ctxid_mask1, TRCCIDCCTLR1);
461 
462 	for (i = 0; i < drvdata->numvmidc; i++)
463 		etm4x_relaxed_write64(csa, config->vmid_val[i], TRCVMIDCVRn(i));
464 	etm4x_relaxed_write32(csa, config->vmid_mask0, TRCVMIDCCTLR0);
465 	if (drvdata->numvmidc > 4)
466 		etm4x_relaxed_write32(csa, config->vmid_mask1, TRCVMIDCCTLR1);
467 
468 	if (!drvdata->skip_power_up) {
469 		u32 trcpdcr = etm4x_relaxed_read32(csa, TRCPDCR);
470 
471 		/*
472 		 * Request to keep the trace unit powered and also
473 		 * emulation of powerdown
474 		 */
475 		etm4x_relaxed_write32(csa, trcpdcr | TRCPDCR_PU, TRCPDCR);
476 	}
477 
478 	/*
479 	 * ETE mandates that the TRCRSR is written to before
480 	 * enabling it.
481 	 */
482 	if (etm4x_is_ete(drvdata))
483 		etm4x_relaxed_write32(csa, TRCRSR_TA, TRCRSR);
484 
485 	etm4x_allow_trace(drvdata);
486 	/* Enable the trace unit */
487 	etm4x_relaxed_write32(csa, 1, TRCPRGCTLR);
488 
489 	/* Synchronize the register updates for sysreg access */
490 	if (!csa->io_mem)
491 		isb();
492 
493 	/* wait for TRCSTATR.IDLE to go back down to '0' */
494 	if (coresight_timeout(csa, TRCSTATR, TRCSTATR_IDLE_BIT, 0))
495 		dev_err(etm_dev,
496 			"timeout while waiting for Idle Trace Status\n");
497 
498 	/*
499 	 * As recommended by section 4.3.7 ("Synchronization when using the
500 	 * memory-mapped interface") of ARM IHI 0064D
501 	 */
502 	dsb(sy);
503 	isb();
504 
505 done:
506 	etm4_cs_lock(drvdata, csa);
507 
508 	dev_dbg(etm_dev, "cpu: %d enable smp call done: %d\n",
509 		drvdata->cpu, rc);
510 	return rc;
511 }
512 
513 static void etm4_enable_hw_smp_call(void *info)
514 {
515 	struct etm4_enable_arg *arg = info;
516 
517 	if (WARN_ON(!arg))
518 		return;
519 	arg->rc = etm4_enable_hw(arg->drvdata);
520 }
521 
522 /*
523  * The goal of function etm4_config_timestamp_event() is to configure a
524  * counter that will tell the tracer to emit a timestamp packet when it
525  * reaches zero.  This is done in order to get a more fine grained idea
526  * of when instructions are executed so that they can be correlated
527  * with execution on other CPUs.
528  *
529  * To do this the counter itself is configured to self reload and
530  * TRCRSCTLR1 (always true) used to get the counter to decrement.  From
531  * there a resource selector is configured with the counter and the
532  * timestamp control register to use the resource selector to trigger the
533  * event that will insert a timestamp packet in the stream.
534  */
535 static int etm4_config_timestamp_event(struct etmv4_drvdata *drvdata)
536 {
537 	int ctridx, ret = -EINVAL;
538 	int counter, rselector;
539 	u32 val = 0;
540 	struct etmv4_config *config = &drvdata->config;
541 
542 	/* No point in trying if we don't have at least one counter */
543 	if (!drvdata->nr_cntr)
544 		goto out;
545 
546 	/* Find a counter that hasn't been initialised */
547 	for (ctridx = 0; ctridx < drvdata->nr_cntr; ctridx++)
548 		if (config->cntr_val[ctridx] == 0)
549 			break;
550 
551 	/* All the counters have been configured already, bail out */
552 	if (ctridx == drvdata->nr_cntr) {
553 		pr_debug("%s: no available counter found\n", __func__);
554 		ret = -ENOSPC;
555 		goto out;
556 	}
557 
558 	/*
559 	 * Searching for an available resource selector to use, starting at
560 	 * '2' since every implementation has at least 2 resource selector.
561 	 * ETMIDR4 gives the number of resource selector _pairs_,
562 	 * hence multiply by 2.
563 	 */
564 	for (rselector = 2; rselector < drvdata->nr_resource * 2; rselector++)
565 		if (!config->res_ctrl[rselector])
566 			break;
567 
568 	if (rselector == drvdata->nr_resource * 2) {
569 		pr_debug("%s: no available resource selector found\n",
570 			 __func__);
571 		ret = -ENOSPC;
572 		goto out;
573 	}
574 
575 	/* Remember what counter we used */
576 	counter = 1 << ctridx;
577 
578 	/*
579 	 * Initialise original and reload counter value to the smallest
580 	 * possible value in order to get as much precision as we can.
581 	 */
582 	config->cntr_val[ctridx] = 1;
583 	config->cntrldvr[ctridx] = 1;
584 
585 	/* Set the trace counter control register */
586 	val =  0x1 << 16	|  /* Bit 16, reload counter automatically */
587 	       0x0 << 7		|  /* Select single resource selector */
588 	       0x1;		   /* Resource selector 1, i.e always true */
589 
590 	config->cntr_ctrl[ctridx] = val;
591 
592 	val = 0x2 << 16		| /* Group 0b0010 - Counter and sequencers */
593 	      counter << 0;	  /* Counter to use */
594 
595 	config->res_ctrl[rselector] = val;
596 
597 	val = 0x0 << 7		| /* Select single resource selector */
598 	      rselector;	  /* Resource selector */
599 
600 	config->ts_ctrl = val;
601 
602 	ret = 0;
603 out:
604 	return ret;
605 }
606 
607 static int etm4_parse_event_config(struct coresight_device *csdev,
608 				   struct perf_event *event)
609 {
610 	int ret = 0;
611 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
612 	struct etmv4_config *config = &drvdata->config;
613 	struct perf_event_attr *attr = &event->attr;
614 	unsigned long cfg_hash;
615 	int preset;
616 
617 	/* Clear configuration from previous run */
618 	memset(config, 0, sizeof(struct etmv4_config));
619 
620 	if (attr->exclude_kernel)
621 		config->mode = ETM_MODE_EXCL_KERN;
622 
623 	if (attr->exclude_user)
624 		config->mode = ETM_MODE_EXCL_USER;
625 
626 	/* Always start from the default config */
627 	etm4_set_default_config(config);
628 
629 	/* Configure filters specified on the perf cmd line, if any. */
630 	ret = etm4_set_event_filters(drvdata, event);
631 	if (ret)
632 		goto out;
633 
634 	/* Go from generic option to ETMv4 specifics */
635 	if (attr->config & BIT(ETM_OPT_CYCACC)) {
636 		config->cfg |= TRCCONFIGR_CCI;
637 		/* TRM: Must program this for cycacc to work */
638 		config->ccctlr = ETM_CYC_THRESHOLD_DEFAULT;
639 	}
640 	if (attr->config & BIT(ETM_OPT_TS)) {
641 		/*
642 		 * Configure timestamps to be emitted at regular intervals in
643 		 * order to correlate instructions executed on different CPUs
644 		 * (CPU-wide trace scenarios).
645 		 */
646 		ret = etm4_config_timestamp_event(drvdata);
647 
648 		/*
649 		 * No need to go further if timestamp intervals can't
650 		 * be configured.
651 		 */
652 		if (ret)
653 			goto out;
654 
655 		/* bit[11], Global timestamp tracing bit */
656 		config->cfg |= TRCCONFIGR_TS;
657 	}
658 
659 	/* Only trace contextID when runs in root PID namespace */
660 	if ((attr->config & BIT(ETM_OPT_CTXTID)) &&
661 	    task_is_in_init_pid_ns(current))
662 		/* bit[6], Context ID tracing bit */
663 		config->cfg |= TRCCONFIGR_CID;
664 
665 	/*
666 	 * If set bit ETM_OPT_CTXTID2 in perf config, this asks to trace VMID
667 	 * for recording CONTEXTIDR_EL2.  Do not enable VMID tracing if the
668 	 * kernel is not running in EL2.
669 	 */
670 	if (attr->config & BIT(ETM_OPT_CTXTID2)) {
671 		if (!is_kernel_in_hyp_mode()) {
672 			ret = -EINVAL;
673 			goto out;
674 		}
675 		/* Only trace virtual contextID when runs in root PID namespace */
676 		if (task_is_in_init_pid_ns(current))
677 			config->cfg |= TRCCONFIGR_VMID | TRCCONFIGR_VMIDOPT;
678 	}
679 
680 	/* return stack - enable if selected and supported */
681 	if ((attr->config & BIT(ETM_OPT_RETSTK)) && drvdata->retstack)
682 		/* bit[12], Return stack enable bit */
683 		config->cfg |= TRCCONFIGR_RS;
684 
685 	/*
686 	 * Set any selected configuration and preset.
687 	 *
688 	 * This extracts the values of PMU_FORMAT_ATTR(configid) and PMU_FORMAT_ATTR(preset)
689 	 * in the perf attributes defined in coresight-etm-perf.c.
690 	 * configid uses bits 63:32 of attr->config2, preset uses bits 3:0 of attr->config.
691 	 * A zero configid means no configuration active, preset = 0 means no preset selected.
692 	 */
693 	if (attr->config2 & GENMASK_ULL(63, 32)) {
694 		cfg_hash = (u32)(attr->config2 >> 32);
695 		preset = attr->config & 0xF;
696 		ret = cscfg_csdev_enable_active_config(csdev, cfg_hash, preset);
697 	}
698 
699 	/* branch broadcast - enable if selected and supported */
700 	if (attr->config & BIT(ETM_OPT_BRANCH_BROADCAST)) {
701 		if (!drvdata->trcbb) {
702 			/*
703 			 * Missing BB support could cause silent decode errors
704 			 * so fail to open if it's not supported.
705 			 */
706 			ret = -EINVAL;
707 			goto out;
708 		} else {
709 			config->cfg |= BIT(ETM4_CFG_BIT_BB);
710 		}
711 	}
712 
713 out:
714 	return ret;
715 }
716 
717 static int etm4_enable_perf(struct coresight_device *csdev,
718 			    struct perf_event *event)
719 {
720 	int ret = 0;
721 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
722 
723 	if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id())) {
724 		ret = -EINVAL;
725 		goto out;
726 	}
727 
728 	/* Configure the tracer based on the session's specifics */
729 	ret = etm4_parse_event_config(csdev, event);
730 	if (ret)
731 		goto out;
732 	/* And enable it */
733 	ret = etm4_enable_hw(drvdata);
734 
735 out:
736 	return ret;
737 }
738 
739 static int etm4_enable_sysfs(struct coresight_device *csdev)
740 {
741 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
742 	struct etm4_enable_arg arg = { };
743 	unsigned long cfg_hash;
744 	int ret, preset;
745 
746 	/* enable any config activated by configfs */
747 	cscfg_config_sysfs_get_active_cfg(&cfg_hash, &preset);
748 	if (cfg_hash) {
749 		ret = cscfg_csdev_enable_active_config(csdev, cfg_hash, preset);
750 		if (ret)
751 			return ret;
752 	}
753 
754 	spin_lock(&drvdata->spinlock);
755 
756 	/*
757 	 * Executing etm4_enable_hw on the cpu whose ETM is being enabled
758 	 * ensures that register writes occur when cpu is powered.
759 	 */
760 	arg.drvdata = drvdata;
761 	ret = smp_call_function_single(drvdata->cpu,
762 				       etm4_enable_hw_smp_call, &arg, 1);
763 	if (!ret)
764 		ret = arg.rc;
765 	if (!ret)
766 		drvdata->sticky_enable = true;
767 	spin_unlock(&drvdata->spinlock);
768 
769 	if (!ret)
770 		dev_dbg(&csdev->dev, "ETM tracing enabled\n");
771 	return ret;
772 }
773 
774 static int etm4_enable(struct coresight_device *csdev,
775 		       struct perf_event *event, u32 mode)
776 {
777 	int ret;
778 	u32 val;
779 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
780 
781 	val = local_cmpxchg(&drvdata->mode, CS_MODE_DISABLED, mode);
782 
783 	/* Someone is already using the tracer */
784 	if (val)
785 		return -EBUSY;
786 
787 	switch (mode) {
788 	case CS_MODE_SYSFS:
789 		ret = etm4_enable_sysfs(csdev);
790 		break;
791 	case CS_MODE_PERF:
792 		ret = etm4_enable_perf(csdev, event);
793 		break;
794 	default:
795 		ret = -EINVAL;
796 	}
797 
798 	/* The tracer didn't start */
799 	if (ret)
800 		local_set(&drvdata->mode, CS_MODE_DISABLED);
801 
802 	return ret;
803 }
804 
805 static void etm4_disable_hw(void *info)
806 {
807 	u32 control;
808 	struct etmv4_drvdata *drvdata = info;
809 	struct etmv4_config *config = &drvdata->config;
810 	struct coresight_device *csdev = drvdata->csdev;
811 	struct device *etm_dev = &csdev->dev;
812 	struct csdev_access *csa = &csdev->access;
813 	int i;
814 
815 	etm4_cs_unlock(drvdata, csa);
816 	etm4_disable_arch_specific(drvdata);
817 
818 	if (!drvdata->skip_power_up) {
819 		/* power can be removed from the trace unit now */
820 		control = etm4x_relaxed_read32(csa, TRCPDCR);
821 		control &= ~TRCPDCR_PU;
822 		etm4x_relaxed_write32(csa, control, TRCPDCR);
823 	}
824 
825 	control = etm4x_relaxed_read32(csa, TRCPRGCTLR);
826 
827 	/* EN, bit[0] Trace unit enable bit */
828 	control &= ~0x1;
829 
830 	/*
831 	 * If the CPU supports v8.4 Trace filter Control,
832 	 * set the ETM to trace prohibited region.
833 	 */
834 	etm4x_prohibit_trace(drvdata);
835 	/*
836 	 * Make sure everything completes before disabling, as recommended
837 	 * by section 7.3.77 ("TRCVICTLR, ViewInst Main Control Register,
838 	 * SSTATUS") of ARM IHI 0064D
839 	 */
840 	dsb(sy);
841 	isb();
842 	/* Trace synchronization barrier, is a nop if not supported */
843 	tsb_csync();
844 	etm4x_relaxed_write32(csa, control, TRCPRGCTLR);
845 
846 	/* wait for TRCSTATR.PMSTABLE to go to '1' */
847 	if (coresight_timeout(csa, TRCSTATR, TRCSTATR_PMSTABLE_BIT, 1))
848 		dev_err(etm_dev,
849 			"timeout while waiting for PM stable Trace Status\n");
850 	/* read the status of the single shot comparators */
851 	for (i = 0; i < drvdata->nr_ss_cmp; i++) {
852 		config->ss_status[i] =
853 			etm4x_relaxed_read32(csa, TRCSSCSRn(i));
854 	}
855 
856 	/* read back the current counter values */
857 	for (i = 0; i < drvdata->nr_cntr; i++) {
858 		config->cntr_val[i] =
859 			etm4x_relaxed_read32(csa, TRCCNTVRn(i));
860 	}
861 
862 	coresight_disclaim_device_unlocked(csdev);
863 	etm4_cs_lock(drvdata, csa);
864 
865 	dev_dbg(&drvdata->csdev->dev,
866 		"cpu: %d disable smp call done\n", drvdata->cpu);
867 }
868 
869 static int etm4_disable_perf(struct coresight_device *csdev,
870 			     struct perf_event *event)
871 {
872 	u32 control;
873 	struct etm_filters *filters = event->hw.addr_filters;
874 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
875 	struct perf_event_attr *attr = &event->attr;
876 
877 	if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id()))
878 		return -EINVAL;
879 
880 	etm4_disable_hw(drvdata);
881 	/*
882 	 * The config_id occupies bits 63:32 of the config2 perf event attr
883 	 * field. If this is non-zero then we will have enabled a config.
884 	 */
885 	if (attr->config2 & GENMASK_ULL(63, 32))
886 		cscfg_csdev_disable_active_config(csdev);
887 
888 	/*
889 	 * Check if the start/stop logic was active when the unit was stopped.
890 	 * That way we can re-enable the start/stop logic when the process is
891 	 * scheduled again.  Configuration of the start/stop logic happens in
892 	 * function etm4_set_event_filters().
893 	 */
894 	control = etm4x_relaxed_read32(&csdev->access, TRCVICTLR);
895 	/* TRCVICTLR::SSSTATUS, bit[9] */
896 	filters->ssstatus = (control & BIT(9));
897 
898 	return 0;
899 }
900 
901 static void etm4_disable_sysfs(struct coresight_device *csdev)
902 {
903 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
904 
905 	/*
906 	 * Taking hotplug lock here protects from clocks getting disabled
907 	 * with tracing being left on (crash scenario) if user disable occurs
908 	 * after cpu online mask indicates the cpu is offline but before the
909 	 * DYING hotplug callback is serviced by the ETM driver.
910 	 */
911 	cpus_read_lock();
912 	spin_lock(&drvdata->spinlock);
913 
914 	/*
915 	 * Executing etm4_disable_hw on the cpu whose ETM is being disabled
916 	 * ensures that register writes occur when cpu is powered.
917 	 */
918 	smp_call_function_single(drvdata->cpu, etm4_disable_hw, drvdata, 1);
919 
920 	spin_unlock(&drvdata->spinlock);
921 	cpus_read_unlock();
922 
923 	dev_dbg(&csdev->dev, "ETM tracing disabled\n");
924 }
925 
926 static void etm4_disable(struct coresight_device *csdev,
927 			 struct perf_event *event)
928 {
929 	u32 mode;
930 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
931 
932 	/*
933 	 * For as long as the tracer isn't disabled another entity can't
934 	 * change its status.  As such we can read the status here without
935 	 * fearing it will change under us.
936 	 */
937 	mode = local_read(&drvdata->mode);
938 
939 	switch (mode) {
940 	case CS_MODE_DISABLED:
941 		break;
942 	case CS_MODE_SYSFS:
943 		etm4_disable_sysfs(csdev);
944 		break;
945 	case CS_MODE_PERF:
946 		etm4_disable_perf(csdev, event);
947 		break;
948 	}
949 
950 	if (mode)
951 		local_set(&drvdata->mode, CS_MODE_DISABLED);
952 }
953 
954 static const struct coresight_ops_source etm4_source_ops = {
955 	.cpu_id		= etm4_cpu_id,
956 	.trace_id	= etm4_trace_id,
957 	.enable		= etm4_enable,
958 	.disable	= etm4_disable,
959 };
960 
961 static const struct coresight_ops etm4_cs_ops = {
962 	.source_ops	= &etm4_source_ops,
963 };
964 
965 static inline bool cpu_supports_sysreg_trace(void)
966 {
967 	u64 dfr0 = read_sysreg_s(SYS_ID_AA64DFR0_EL1);
968 
969 	return ((dfr0 >> ID_AA64DFR0_TRACEVER_SHIFT) & 0xfUL) > 0;
970 }
971 
972 static bool etm4_init_sysreg_access(struct etmv4_drvdata *drvdata,
973 				    struct csdev_access *csa)
974 {
975 	u32 devarch;
976 
977 	if (!cpu_supports_sysreg_trace())
978 		return false;
979 
980 	/*
981 	 * ETMs implementing sysreg access must implement TRCDEVARCH.
982 	 */
983 	devarch = read_etm4x_sysreg_const_offset(TRCDEVARCH);
984 	switch (devarch & ETM_DEVARCH_ID_MASK) {
985 	case ETM_DEVARCH_ETMv4x_ARCH:
986 		*csa = (struct csdev_access) {
987 			.io_mem	= false,
988 			.read	= etm4x_sysreg_read,
989 			.write	= etm4x_sysreg_write,
990 		};
991 		break;
992 	case ETM_DEVARCH_ETE_ARCH:
993 		*csa = (struct csdev_access) {
994 			.io_mem	= false,
995 			.read	= ete_sysreg_read,
996 			.write	= ete_sysreg_write,
997 		};
998 		break;
999 	default:
1000 		return false;
1001 	}
1002 
1003 	drvdata->arch = etm_devarch_to_arch(devarch);
1004 	return true;
1005 }
1006 
1007 static bool etm4_init_iomem_access(struct etmv4_drvdata *drvdata,
1008 				   struct csdev_access *csa)
1009 {
1010 	u32 devarch = readl_relaxed(drvdata->base + TRCDEVARCH);
1011 	u32 idr1 = readl_relaxed(drvdata->base + TRCIDR1);
1012 
1013 	/*
1014 	 * All ETMs must implement TRCDEVARCH to indicate that
1015 	 * the component is an ETMv4. To support any broken
1016 	 * implementations we fall back to TRCIDR1 check, which
1017 	 * is not really reliable.
1018 	 */
1019 	if ((devarch & ETM_DEVARCH_ID_MASK) == ETM_DEVARCH_ETMv4x_ARCH) {
1020 		drvdata->arch = etm_devarch_to_arch(devarch);
1021 	} else {
1022 		pr_warn("CPU%d: ETM4x incompatible TRCDEVARCH: %x, falling back to TRCIDR1\n",
1023 			smp_processor_id(), devarch);
1024 
1025 		if (ETM_TRCIDR1_ARCH_MAJOR(idr1) != ETM_TRCIDR1_ARCH_ETMv4)
1026 			return false;
1027 		drvdata->arch = etm_trcidr_to_arch(idr1);
1028 	}
1029 
1030 	*csa = CSDEV_ACCESS_IOMEM(drvdata->base);
1031 	return true;
1032 }
1033 
1034 static bool etm4_init_csdev_access(struct etmv4_drvdata *drvdata,
1035 				   struct csdev_access *csa)
1036 {
1037 	/*
1038 	 * Always choose the memory mapped io, if there is
1039 	 * a memory map to prevent sysreg access on broken
1040 	 * systems.
1041 	 */
1042 	if (drvdata->base)
1043 		return etm4_init_iomem_access(drvdata, csa);
1044 
1045 	if (etm4_init_sysreg_access(drvdata, csa))
1046 		return true;
1047 
1048 	return false;
1049 }
1050 
1051 static void cpu_detect_trace_filtering(struct etmv4_drvdata *drvdata)
1052 {
1053 	u64 dfr0 = read_sysreg(id_aa64dfr0_el1);
1054 	u64 trfcr;
1055 
1056 	drvdata->trfcr = 0;
1057 	if (!cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_TRACE_FILT_SHIFT))
1058 		return;
1059 
1060 	/*
1061 	 * If the CPU supports v8.4 SelfHosted Tracing, enable
1062 	 * tracing at the kernel EL and EL0, forcing to use the
1063 	 * virtual time as the timestamp.
1064 	 */
1065 	trfcr = (TRFCR_ELx_TS_VIRTUAL |
1066 		 TRFCR_ELx_ExTRE |
1067 		 TRFCR_ELx_E0TRE);
1068 
1069 	/* If we are running at EL2, allow tracing the CONTEXTIDR_EL2. */
1070 	if (is_kernel_in_hyp_mode())
1071 		trfcr |= TRFCR_EL2_CX;
1072 
1073 	drvdata->trfcr = trfcr;
1074 }
1075 
1076 static void etm4_init_arch_data(void *info)
1077 {
1078 	u32 etmidr0;
1079 	u32 etmidr2;
1080 	u32 etmidr3;
1081 	u32 etmidr4;
1082 	u32 etmidr5;
1083 	struct etm4_init_arg *init_arg = info;
1084 	struct etmv4_drvdata *drvdata;
1085 	struct csdev_access *csa;
1086 	int i;
1087 
1088 	drvdata = init_arg->drvdata;
1089 	csa = init_arg->csa;
1090 
1091 	/*
1092 	 * If we are unable to detect the access mechanism,
1093 	 * or unable to detect the trace unit type, fail
1094 	 * early.
1095 	 */
1096 	if (!etm4_init_csdev_access(drvdata, csa))
1097 		return;
1098 
1099 	/* Detect the support for OS Lock before we actually use it */
1100 	etm_detect_os_lock(drvdata, csa);
1101 
1102 	/* Make sure all registers are accessible */
1103 	etm4_os_unlock_csa(drvdata, csa);
1104 	etm4_cs_unlock(drvdata, csa);
1105 
1106 	etm4_check_arch_features(drvdata, init_arg->pid);
1107 
1108 	/* find all capabilities of the tracing unit */
1109 	etmidr0 = etm4x_relaxed_read32(csa, TRCIDR0);
1110 
1111 	/* INSTP0, bits[2:1] P0 tracing support field */
1112 	drvdata->instrp0 = !!(FIELD_GET(TRCIDR0_INSTP0_MASK, etmidr0) == 0b11);
1113 	/* TRCBB, bit[5] Branch broadcast tracing support bit */
1114 	drvdata->trcbb = !!(etmidr0 & TRCIDR0_TRCBB);
1115 	/* TRCCOND, bit[6] Conditional instruction tracing support bit */
1116 	drvdata->trccond = !!(etmidr0 & TRCIDR0_TRCCOND);
1117 	/* TRCCCI, bit[7] Cycle counting instruction bit */
1118 	drvdata->trccci = !!(etmidr0 & TRCIDR0_TRCCCI);
1119 	/* RETSTACK, bit[9] Return stack bit */
1120 	drvdata->retstack = !!(etmidr0 & TRCIDR0_RETSTACK);
1121 	/* NUMEVENT, bits[11:10] Number of events field */
1122 	drvdata->nr_event = FIELD_GET(TRCIDR0_NUMEVENT_MASK, etmidr0);
1123 	/* QSUPP, bits[16:15] Q element support field */
1124 	drvdata->q_support = FIELD_GET(TRCIDR0_QSUPP_MASK, etmidr0);
1125 	/* TSSIZE, bits[28:24] Global timestamp size field */
1126 	drvdata->ts_size = FIELD_GET(TRCIDR0_TSSIZE_MASK, etmidr0);
1127 
1128 	/* maximum size of resources */
1129 	etmidr2 = etm4x_relaxed_read32(csa, TRCIDR2);
1130 	/* CIDSIZE, bits[9:5] Indicates the Context ID size */
1131 	drvdata->ctxid_size = FIELD_GET(TRCIDR2_CIDSIZE_MASK, etmidr2);
1132 	/* VMIDSIZE, bits[14:10] Indicates the VMID size */
1133 	drvdata->vmid_size = FIELD_GET(TRCIDR2_VMIDSIZE_MASK, etmidr2);
1134 	/* CCSIZE, bits[28:25] size of the cycle counter in bits minus 12 */
1135 	drvdata->ccsize = FIELD_GET(TRCIDR2_CCSIZE_MASK, etmidr2);
1136 
1137 	etmidr3 = etm4x_relaxed_read32(csa, TRCIDR3);
1138 	/* CCITMIN, bits[11:0] minimum threshold value that can be programmed */
1139 	drvdata->ccitmin = FIELD_GET(TRCIDR3_CCITMIN_MASK, etmidr3);
1140 	/* EXLEVEL_S, bits[19:16] Secure state instruction tracing */
1141 	drvdata->s_ex_level = FIELD_GET(TRCIDR3_EXLEVEL_S_MASK, etmidr3);
1142 	drvdata->config.s_ex_level = drvdata->s_ex_level;
1143 	/* EXLEVEL_NS, bits[23:20] Non-secure state instruction tracing */
1144 	drvdata->ns_ex_level = FIELD_GET(TRCIDR3_EXLEVEL_NS_MASK, etmidr3);
1145 	/*
1146 	 * TRCERR, bit[24] whether a trace unit can trace a
1147 	 * system error exception.
1148 	 */
1149 	drvdata->trc_error = !!(etmidr3 & TRCIDR3_TRCERR);
1150 	/* SYNCPR, bit[25] implementation has a fixed synchronization period? */
1151 	drvdata->syncpr = !!(etmidr3 & TRCIDR3_SYNCPR);
1152 	/* STALLCTL, bit[26] is stall control implemented? */
1153 	drvdata->stallctl = !!(etmidr3 & TRCIDR3_STALLCTL);
1154 	/* SYSSTALL, bit[27] implementation can support stall control? */
1155 	drvdata->sysstall = !!(etmidr3 & TRCIDR3_SYSSTALL);
1156 	/*
1157 	 * NUMPROC - the number of PEs available for tracing, 5bits
1158 	 *         = TRCIDR3.bits[13:12]bits[30:28]
1159 	 *  bits[4:3] = TRCIDR3.bits[13:12] (since etm-v4.2, otherwise RES0)
1160 	 *  bits[3:0] = TRCIDR3.bits[30:28]
1161 	 */
1162 	drvdata->nr_pe =  (FIELD_GET(TRCIDR3_NUMPROC_HI_MASK, etmidr3) << 3) |
1163 			   FIELD_GET(TRCIDR3_NUMPROC_LO_MASK, etmidr3);
1164 	/* NOOVERFLOW, bit[31] is trace overflow prevention supported */
1165 	drvdata->nooverflow = !!(etmidr3 & TRCIDR3_NOOVERFLOW);
1166 
1167 	/* number of resources trace unit supports */
1168 	etmidr4 = etm4x_relaxed_read32(csa, TRCIDR4);
1169 	/* NUMACPAIRS, bits[0:3] number of addr comparator pairs for tracing */
1170 	drvdata->nr_addr_cmp = FIELD_GET(TRCIDR4_NUMACPAIRS_MASK, etmidr4);
1171 	/* NUMPC, bits[15:12] number of PE comparator inputs for tracing */
1172 	drvdata->nr_pe_cmp = FIELD_GET(TRCIDR4_NUMPC_MASK, etmidr4);
1173 	/*
1174 	 * NUMRSPAIR, bits[19:16]
1175 	 * The number of resource pairs conveyed by the HW starts at 0, i.e a
1176 	 * value of 0x0 indicate 1 resource pair, 0x1 indicate two and so on.
1177 	 * As such add 1 to the value of NUMRSPAIR for a better representation.
1178 	 *
1179 	 * For ETM v4.3 and later, 0x0 means 0, and no pairs are available -
1180 	 * the default TRUE and FALSE resource selectors are omitted.
1181 	 * Otherwise for values 0x1 and above the number is N + 1 as per v4.2.
1182 	 */
1183 	drvdata->nr_resource = FIELD_GET(TRCIDR4_NUMRSPAIR_MASK, etmidr4);
1184 	if ((drvdata->arch < ETM_ARCH_V4_3) || (drvdata->nr_resource > 0))
1185 		drvdata->nr_resource += 1;
1186 	/*
1187 	 * NUMSSCC, bits[23:20] the number of single-shot
1188 	 * comparator control for tracing. Read any status regs as these
1189 	 * also contain RO capability data.
1190 	 */
1191 	drvdata->nr_ss_cmp = FIELD_GET(TRCIDR4_NUMSSCC_MASK, etmidr4);
1192 	for (i = 0; i < drvdata->nr_ss_cmp; i++) {
1193 		drvdata->config.ss_status[i] =
1194 			etm4x_relaxed_read32(csa, TRCSSCSRn(i));
1195 	}
1196 	/* NUMCIDC, bits[27:24] number of Context ID comparators for tracing */
1197 	drvdata->numcidc = FIELD_GET(TRCIDR4_NUMCIDC_MASK, etmidr4);
1198 	/* NUMVMIDC, bits[31:28] number of VMID comparators for tracing */
1199 	drvdata->numvmidc = FIELD_GET(TRCIDR4_NUMVMIDC_MASK, etmidr4);
1200 
1201 	etmidr5 = etm4x_relaxed_read32(csa, TRCIDR5);
1202 	/* NUMEXTIN, bits[8:0] number of external inputs implemented */
1203 	drvdata->nr_ext_inp = FIELD_GET(TRCIDR5_NUMEXTIN_MASK, etmidr5);
1204 	/* TRACEIDSIZE, bits[21:16] indicates the trace ID width */
1205 	drvdata->trcid_size = FIELD_GET(TRCIDR5_TRACEIDSIZE_MASK, etmidr5);
1206 	/* ATBTRIG, bit[22] implementation can support ATB triggers? */
1207 	drvdata->atbtrig = !!(etmidr5 & TRCIDR5_ATBTRIG);
1208 	/*
1209 	 * LPOVERRIDE, bit[23] implementation supports
1210 	 * low-power state override
1211 	 */
1212 	drvdata->lpoverride = (etmidr5 & TRCIDR5_LPOVERRIDE) && (!drvdata->skip_power_up);
1213 	/* NUMSEQSTATE, bits[27:25] number of sequencer states implemented */
1214 	drvdata->nrseqstate = FIELD_GET(TRCIDR5_NUMSEQSTATE_MASK, etmidr5);
1215 	/* NUMCNTR, bits[30:28] number of counters available for tracing */
1216 	drvdata->nr_cntr = FIELD_GET(TRCIDR5_NUMCNTR_MASK, etmidr5);
1217 	etm4_cs_lock(drvdata, csa);
1218 	cpu_detect_trace_filtering(drvdata);
1219 }
1220 
1221 static inline u32 etm4_get_victlr_access_type(struct etmv4_config *config)
1222 {
1223 	return etm4_get_access_type(config) << __bf_shf(TRCVICTLR_EXLEVEL_MASK);
1224 }
1225 
1226 /* Set ELx trace filter access in the TRCVICTLR register */
1227 static void etm4_set_victlr_access(struct etmv4_config *config)
1228 {
1229 	config->vinst_ctrl &= ~TRCVICTLR_EXLEVEL_MASK;
1230 	config->vinst_ctrl |= etm4_get_victlr_access_type(config);
1231 }
1232 
1233 static void etm4_set_default_config(struct etmv4_config *config)
1234 {
1235 	/* disable all events tracing */
1236 	config->eventctrl0 = 0x0;
1237 	config->eventctrl1 = 0x0;
1238 
1239 	/* disable stalling */
1240 	config->stall_ctrl = 0x0;
1241 
1242 	/* enable trace synchronization every 4096 bytes, if available */
1243 	config->syncfreq = 0xC;
1244 
1245 	/* disable timestamp event */
1246 	config->ts_ctrl = 0x0;
1247 
1248 	/* TRCVICTLR::EVENT = 0x01, select the always on logic */
1249 	config->vinst_ctrl = FIELD_PREP(TRCVICTLR_EVENT_MASK, 0x01);
1250 
1251 	/* TRCVICTLR::EXLEVEL_NS:EXLEVELS: Set kernel / user filtering */
1252 	etm4_set_victlr_access(config);
1253 }
1254 
1255 static u64 etm4_get_ns_access_type(struct etmv4_config *config)
1256 {
1257 	u64 access_type = 0;
1258 
1259 	/*
1260 	 * EXLEVEL_NS, for NonSecure Exception levels.
1261 	 * The mask here is a generic value and must be
1262 	 * shifted to the corresponding field for the registers
1263 	 */
1264 	if (!is_kernel_in_hyp_mode()) {
1265 		/* Stay away from hypervisor mode for non-VHE */
1266 		access_type =  ETM_EXLEVEL_NS_HYP;
1267 		if (config->mode & ETM_MODE_EXCL_KERN)
1268 			access_type |= ETM_EXLEVEL_NS_OS;
1269 	} else if (config->mode & ETM_MODE_EXCL_KERN) {
1270 		access_type = ETM_EXLEVEL_NS_HYP;
1271 	}
1272 
1273 	if (config->mode & ETM_MODE_EXCL_USER)
1274 		access_type |= ETM_EXLEVEL_NS_APP;
1275 
1276 	return access_type;
1277 }
1278 
1279 /*
1280  * Construct the exception level masks for a given config.
1281  * This must be shifted to the corresponding register field
1282  * for usage.
1283  */
1284 static u64 etm4_get_access_type(struct etmv4_config *config)
1285 {
1286 	/* All Secure exception levels are excluded from the trace */
1287 	return etm4_get_ns_access_type(config) | (u64)config->s_ex_level;
1288 }
1289 
1290 static u64 etm4_get_comparator_access_type(struct etmv4_config *config)
1291 {
1292 	return etm4_get_access_type(config) << TRCACATR_EXLEVEL_SHIFT;
1293 }
1294 
1295 static void etm4_set_comparator_filter(struct etmv4_config *config,
1296 				       u64 start, u64 stop, int comparator)
1297 {
1298 	u64 access_type = etm4_get_comparator_access_type(config);
1299 
1300 	/* First half of default address comparator */
1301 	config->addr_val[comparator] = start;
1302 	config->addr_acc[comparator] = access_type;
1303 	config->addr_type[comparator] = ETM_ADDR_TYPE_RANGE;
1304 
1305 	/* Second half of default address comparator */
1306 	config->addr_val[comparator + 1] = stop;
1307 	config->addr_acc[comparator + 1] = access_type;
1308 	config->addr_type[comparator + 1] = ETM_ADDR_TYPE_RANGE;
1309 
1310 	/*
1311 	 * Configure the ViewInst function to include this address range
1312 	 * comparator.
1313 	 *
1314 	 * @comparator is divided by two since it is the index in the
1315 	 * etmv4_config::addr_val array but register TRCVIIECTLR deals with
1316 	 * address range comparator _pairs_.
1317 	 *
1318 	 * Therefore:
1319 	 *	index 0 -> compatator pair 0
1320 	 *	index 2 -> comparator pair 1
1321 	 *	index 4 -> comparator pair 2
1322 	 *	...
1323 	 *	index 14 -> comparator pair 7
1324 	 */
1325 	config->viiectlr |= BIT(comparator / 2);
1326 }
1327 
1328 static void etm4_set_start_stop_filter(struct etmv4_config *config,
1329 				       u64 address, int comparator,
1330 				       enum etm_addr_type type)
1331 {
1332 	int shift;
1333 	u64 access_type = etm4_get_comparator_access_type(config);
1334 
1335 	/* Configure the comparator */
1336 	config->addr_val[comparator] = address;
1337 	config->addr_acc[comparator] = access_type;
1338 	config->addr_type[comparator] = type;
1339 
1340 	/*
1341 	 * Configure ViewInst Start-Stop control register.
1342 	 * Addresses configured to start tracing go from bit 0 to n-1,
1343 	 * while those configured to stop tracing from 16 to 16 + n-1.
1344 	 */
1345 	shift = (type == ETM_ADDR_TYPE_START ? 0 : 16);
1346 	config->vissctlr |= BIT(shift + comparator);
1347 }
1348 
1349 static void etm4_set_default_filter(struct etmv4_config *config)
1350 {
1351 	/* Trace everything 'default' filter achieved by no filtering */
1352 	config->viiectlr = 0x0;
1353 
1354 	/*
1355 	 * TRCVICTLR::SSSTATUS == 1, the start-stop logic is
1356 	 * in the started state
1357 	 */
1358 	config->vinst_ctrl |= TRCVICTLR_SSSTATUS;
1359 	config->mode |= ETM_MODE_VIEWINST_STARTSTOP;
1360 
1361 	/* No start-stop filtering for ViewInst */
1362 	config->vissctlr = 0x0;
1363 }
1364 
1365 static void etm4_set_default(struct etmv4_config *config)
1366 {
1367 	if (WARN_ON_ONCE(!config))
1368 		return;
1369 
1370 	/*
1371 	 * Make default initialisation trace everything
1372 	 *
1373 	 * This is done by a minimum default config sufficient to enable
1374 	 * full instruction trace - with a default filter for trace all
1375 	 * achieved by having no filtering.
1376 	 */
1377 	etm4_set_default_config(config);
1378 	etm4_set_default_filter(config);
1379 }
1380 
1381 static int etm4_get_next_comparator(struct etmv4_drvdata *drvdata, u32 type)
1382 {
1383 	int nr_comparator, index = 0;
1384 	struct etmv4_config *config = &drvdata->config;
1385 
1386 	/*
1387 	 * nr_addr_cmp holds the number of comparator _pair_, so time 2
1388 	 * for the total number of comparators.
1389 	 */
1390 	nr_comparator = drvdata->nr_addr_cmp * 2;
1391 
1392 	/* Go through the tally of comparators looking for a free one. */
1393 	while (index < nr_comparator) {
1394 		switch (type) {
1395 		case ETM_ADDR_TYPE_RANGE:
1396 			if (config->addr_type[index] == ETM_ADDR_TYPE_NONE &&
1397 			    config->addr_type[index + 1] == ETM_ADDR_TYPE_NONE)
1398 				return index;
1399 
1400 			/* Address range comparators go in pairs */
1401 			index += 2;
1402 			break;
1403 		case ETM_ADDR_TYPE_START:
1404 		case ETM_ADDR_TYPE_STOP:
1405 			if (config->addr_type[index] == ETM_ADDR_TYPE_NONE)
1406 				return index;
1407 
1408 			/* Start/stop address can have odd indexes */
1409 			index += 1;
1410 			break;
1411 		default:
1412 			return -EINVAL;
1413 		}
1414 	}
1415 
1416 	/* If we are here all the comparators have been used. */
1417 	return -ENOSPC;
1418 }
1419 
1420 static int etm4_set_event_filters(struct etmv4_drvdata *drvdata,
1421 				  struct perf_event *event)
1422 {
1423 	int i, comparator, ret = 0;
1424 	u64 address;
1425 	struct etmv4_config *config = &drvdata->config;
1426 	struct etm_filters *filters = event->hw.addr_filters;
1427 
1428 	if (!filters)
1429 		goto default_filter;
1430 
1431 	/* Sync events with what Perf got */
1432 	perf_event_addr_filters_sync(event);
1433 
1434 	/*
1435 	 * If there are no filters to deal with simply go ahead with
1436 	 * the default filter, i.e the entire address range.
1437 	 */
1438 	if (!filters->nr_filters)
1439 		goto default_filter;
1440 
1441 	for (i = 0; i < filters->nr_filters; i++) {
1442 		struct etm_filter *filter = &filters->etm_filter[i];
1443 		enum etm_addr_type type = filter->type;
1444 
1445 		/* See if a comparator is free. */
1446 		comparator = etm4_get_next_comparator(drvdata, type);
1447 		if (comparator < 0) {
1448 			ret = comparator;
1449 			goto out;
1450 		}
1451 
1452 		switch (type) {
1453 		case ETM_ADDR_TYPE_RANGE:
1454 			etm4_set_comparator_filter(config,
1455 						   filter->start_addr,
1456 						   filter->stop_addr,
1457 						   comparator);
1458 			/*
1459 			 * TRCVICTLR::SSSTATUS == 1, the start-stop logic is
1460 			 * in the started state
1461 			 */
1462 			config->vinst_ctrl |= TRCVICTLR_SSSTATUS;
1463 
1464 			/* No start-stop filtering for ViewInst */
1465 			config->vissctlr = 0x0;
1466 			break;
1467 		case ETM_ADDR_TYPE_START:
1468 		case ETM_ADDR_TYPE_STOP:
1469 			/* Get the right start or stop address */
1470 			address = (type == ETM_ADDR_TYPE_START ?
1471 				   filter->start_addr :
1472 				   filter->stop_addr);
1473 
1474 			/* Configure comparator */
1475 			etm4_set_start_stop_filter(config, address,
1476 						   comparator, type);
1477 
1478 			/*
1479 			 * If filters::ssstatus == 1, trace acquisition was
1480 			 * started but the process was yanked away before the
1481 			 * the stop address was hit.  As such the start/stop
1482 			 * logic needs to be re-started so that tracing can
1483 			 * resume where it left.
1484 			 *
1485 			 * The start/stop logic status when a process is
1486 			 * scheduled out is checked in function
1487 			 * etm4_disable_perf().
1488 			 */
1489 			if (filters->ssstatus)
1490 				config->vinst_ctrl |= TRCVICTLR_SSSTATUS;
1491 
1492 			/* No include/exclude filtering for ViewInst */
1493 			config->viiectlr = 0x0;
1494 			break;
1495 		default:
1496 			ret = -EINVAL;
1497 			goto out;
1498 		}
1499 	}
1500 
1501 	goto out;
1502 
1503 
1504 default_filter:
1505 	etm4_set_default_filter(config);
1506 
1507 out:
1508 	return ret;
1509 }
1510 
1511 void etm4_config_trace_mode(struct etmv4_config *config)
1512 {
1513 	u32 mode;
1514 
1515 	mode = config->mode;
1516 	mode &= (ETM_MODE_EXCL_KERN | ETM_MODE_EXCL_USER);
1517 
1518 	/* excluding kernel AND user space doesn't make sense */
1519 	WARN_ON_ONCE(mode == (ETM_MODE_EXCL_KERN | ETM_MODE_EXCL_USER));
1520 
1521 	/* nothing to do if neither flags are set */
1522 	if (!(mode & ETM_MODE_EXCL_KERN) && !(mode & ETM_MODE_EXCL_USER))
1523 		return;
1524 
1525 	etm4_set_victlr_access(config);
1526 }
1527 
1528 static int etm4_online_cpu(unsigned int cpu)
1529 {
1530 	if (!etmdrvdata[cpu])
1531 		return 0;
1532 
1533 	if (etmdrvdata[cpu]->boot_enable && !etmdrvdata[cpu]->sticky_enable)
1534 		coresight_enable(etmdrvdata[cpu]->csdev);
1535 	return 0;
1536 }
1537 
1538 static int etm4_starting_cpu(unsigned int cpu)
1539 {
1540 	if (!etmdrvdata[cpu])
1541 		return 0;
1542 
1543 	spin_lock(&etmdrvdata[cpu]->spinlock);
1544 	if (!etmdrvdata[cpu]->os_unlock)
1545 		etm4_os_unlock(etmdrvdata[cpu]);
1546 
1547 	if (local_read(&etmdrvdata[cpu]->mode))
1548 		etm4_enable_hw(etmdrvdata[cpu]);
1549 	spin_unlock(&etmdrvdata[cpu]->spinlock);
1550 	return 0;
1551 }
1552 
1553 static int etm4_dying_cpu(unsigned int cpu)
1554 {
1555 	if (!etmdrvdata[cpu])
1556 		return 0;
1557 
1558 	spin_lock(&etmdrvdata[cpu]->spinlock);
1559 	if (local_read(&etmdrvdata[cpu]->mode))
1560 		etm4_disable_hw(etmdrvdata[cpu]);
1561 	spin_unlock(&etmdrvdata[cpu]->spinlock);
1562 	return 0;
1563 }
1564 
1565 static void etm4_init_trace_id(struct etmv4_drvdata *drvdata)
1566 {
1567 	drvdata->trcid = coresight_get_trace_id(drvdata->cpu);
1568 }
1569 
1570 static int __etm4_cpu_save(struct etmv4_drvdata *drvdata)
1571 {
1572 	int i, ret = 0;
1573 	struct etmv4_save_state *state;
1574 	struct coresight_device *csdev = drvdata->csdev;
1575 	struct csdev_access *csa;
1576 	struct device *etm_dev;
1577 
1578 	if (WARN_ON(!csdev))
1579 		return -ENODEV;
1580 
1581 	etm_dev = &csdev->dev;
1582 	csa = &csdev->access;
1583 
1584 	/*
1585 	 * As recommended by 3.4.1 ("The procedure when powering down the PE")
1586 	 * of ARM IHI 0064D
1587 	 */
1588 	dsb(sy);
1589 	isb();
1590 
1591 	etm4_cs_unlock(drvdata, csa);
1592 	/* Lock the OS lock to disable trace and external debugger access */
1593 	etm4_os_lock(drvdata);
1594 
1595 	/* wait for TRCSTATR.PMSTABLE to go up */
1596 	if (coresight_timeout(csa, TRCSTATR, TRCSTATR_PMSTABLE_BIT, 1)) {
1597 		dev_err(etm_dev,
1598 			"timeout while waiting for PM Stable Status\n");
1599 		etm4_os_unlock(drvdata);
1600 		ret = -EBUSY;
1601 		goto out;
1602 	}
1603 
1604 	state = drvdata->save_state;
1605 
1606 	state->trcprgctlr = etm4x_read32(csa, TRCPRGCTLR);
1607 	if (drvdata->nr_pe)
1608 		state->trcprocselr = etm4x_read32(csa, TRCPROCSELR);
1609 	state->trcconfigr = etm4x_read32(csa, TRCCONFIGR);
1610 	state->trcauxctlr = etm4x_read32(csa, TRCAUXCTLR);
1611 	state->trceventctl0r = etm4x_read32(csa, TRCEVENTCTL0R);
1612 	state->trceventctl1r = etm4x_read32(csa, TRCEVENTCTL1R);
1613 	if (drvdata->stallctl)
1614 		state->trcstallctlr = etm4x_read32(csa, TRCSTALLCTLR);
1615 	state->trctsctlr = etm4x_read32(csa, TRCTSCTLR);
1616 	state->trcsyncpr = etm4x_read32(csa, TRCSYNCPR);
1617 	state->trcccctlr = etm4x_read32(csa, TRCCCCTLR);
1618 	state->trcbbctlr = etm4x_read32(csa, TRCBBCTLR);
1619 	state->trctraceidr = etm4x_read32(csa, TRCTRACEIDR);
1620 	state->trcqctlr = etm4x_read32(csa, TRCQCTLR);
1621 
1622 	state->trcvictlr = etm4x_read32(csa, TRCVICTLR);
1623 	state->trcviiectlr = etm4x_read32(csa, TRCVIIECTLR);
1624 	state->trcvissctlr = etm4x_read32(csa, TRCVISSCTLR);
1625 	if (drvdata->nr_pe_cmp)
1626 		state->trcvipcssctlr = etm4x_read32(csa, TRCVIPCSSCTLR);
1627 	state->trcvdctlr = etm4x_read32(csa, TRCVDCTLR);
1628 	state->trcvdsacctlr = etm4x_read32(csa, TRCVDSACCTLR);
1629 	state->trcvdarcctlr = etm4x_read32(csa, TRCVDARCCTLR);
1630 
1631 	for (i = 0; i < drvdata->nrseqstate - 1; i++)
1632 		state->trcseqevr[i] = etm4x_read32(csa, TRCSEQEVRn(i));
1633 
1634 	state->trcseqrstevr = etm4x_read32(csa, TRCSEQRSTEVR);
1635 	state->trcseqstr = etm4x_read32(csa, TRCSEQSTR);
1636 	state->trcextinselr = etm4x_read32(csa, TRCEXTINSELR);
1637 
1638 	for (i = 0; i < drvdata->nr_cntr; i++) {
1639 		state->trccntrldvr[i] = etm4x_read32(csa, TRCCNTRLDVRn(i));
1640 		state->trccntctlr[i] = etm4x_read32(csa, TRCCNTCTLRn(i));
1641 		state->trccntvr[i] = etm4x_read32(csa, TRCCNTVRn(i));
1642 	}
1643 
1644 	for (i = 0; i < drvdata->nr_resource * 2; i++)
1645 		state->trcrsctlr[i] = etm4x_read32(csa, TRCRSCTLRn(i));
1646 
1647 	for (i = 0; i < drvdata->nr_ss_cmp; i++) {
1648 		state->trcssccr[i] = etm4x_read32(csa, TRCSSCCRn(i));
1649 		state->trcsscsr[i] = etm4x_read32(csa, TRCSSCSRn(i));
1650 		if (etm4x_sspcicrn_present(drvdata, i))
1651 			state->trcsspcicr[i] = etm4x_read32(csa, TRCSSPCICRn(i));
1652 	}
1653 
1654 	for (i = 0; i < drvdata->nr_addr_cmp * 2; i++) {
1655 		state->trcacvr[i] = etm4x_read64(csa, TRCACVRn(i));
1656 		state->trcacatr[i] = etm4x_read64(csa, TRCACATRn(i));
1657 	}
1658 
1659 	/*
1660 	 * Data trace stream is architecturally prohibited for A profile cores
1661 	 * so we don't save (or later restore) trcdvcvr and trcdvcmr - As per
1662 	 * section 1.3.4 ("Possible functional configurations of an ETMv4 trace
1663 	 * unit") of ARM IHI 0064D.
1664 	 */
1665 
1666 	for (i = 0; i < drvdata->numcidc; i++)
1667 		state->trccidcvr[i] = etm4x_read64(csa, TRCCIDCVRn(i));
1668 
1669 	for (i = 0; i < drvdata->numvmidc; i++)
1670 		state->trcvmidcvr[i] = etm4x_read64(csa, TRCVMIDCVRn(i));
1671 
1672 	state->trccidcctlr0 = etm4x_read32(csa, TRCCIDCCTLR0);
1673 	if (drvdata->numcidc > 4)
1674 		state->trccidcctlr1 = etm4x_read32(csa, TRCCIDCCTLR1);
1675 
1676 	state->trcvmidcctlr0 = etm4x_read32(csa, TRCVMIDCCTLR0);
1677 	if (drvdata->numvmidc > 4)
1678 		state->trcvmidcctlr0 = etm4x_read32(csa, TRCVMIDCCTLR1);
1679 
1680 	state->trcclaimset = etm4x_read32(csa, TRCCLAIMCLR);
1681 
1682 	if (!drvdata->skip_power_up)
1683 		state->trcpdcr = etm4x_read32(csa, TRCPDCR);
1684 
1685 	/* wait for TRCSTATR.IDLE to go up */
1686 	if (coresight_timeout(csa, TRCSTATR, TRCSTATR_IDLE_BIT, 1)) {
1687 		dev_err(etm_dev,
1688 			"timeout while waiting for Idle Trace Status\n");
1689 		etm4_os_unlock(drvdata);
1690 		ret = -EBUSY;
1691 		goto out;
1692 	}
1693 
1694 	drvdata->state_needs_restore = true;
1695 
1696 	/*
1697 	 * Power can be removed from the trace unit now. We do this to
1698 	 * potentially save power on systems that respect the TRCPDCR_PU
1699 	 * despite requesting software to save/restore state.
1700 	 */
1701 	if (!drvdata->skip_power_up)
1702 		etm4x_relaxed_write32(csa, (state->trcpdcr & ~TRCPDCR_PU),
1703 				      TRCPDCR);
1704 out:
1705 	etm4_cs_lock(drvdata, csa);
1706 	return ret;
1707 }
1708 
1709 static int etm4_cpu_save(struct etmv4_drvdata *drvdata)
1710 {
1711 	int ret = 0;
1712 
1713 	/* Save the TRFCR irrespective of whether the ETM is ON */
1714 	if (drvdata->trfcr)
1715 		drvdata->save_trfcr = read_trfcr();
1716 	/*
1717 	 * Save and restore the ETM Trace registers only if
1718 	 * the ETM is active.
1719 	 */
1720 	if (local_read(&drvdata->mode) && drvdata->save_state)
1721 		ret = __etm4_cpu_save(drvdata);
1722 	return ret;
1723 }
1724 
1725 static void __etm4_cpu_restore(struct etmv4_drvdata *drvdata)
1726 {
1727 	int i;
1728 	struct etmv4_save_state *state = drvdata->save_state;
1729 	struct csdev_access tmp_csa = CSDEV_ACCESS_IOMEM(drvdata->base);
1730 	struct csdev_access *csa = &tmp_csa;
1731 
1732 	etm4_cs_unlock(drvdata, csa);
1733 	etm4x_relaxed_write32(csa, state->trcclaimset, TRCCLAIMSET);
1734 
1735 	etm4x_relaxed_write32(csa, state->trcprgctlr, TRCPRGCTLR);
1736 	if (drvdata->nr_pe)
1737 		etm4x_relaxed_write32(csa, state->trcprocselr, TRCPROCSELR);
1738 	etm4x_relaxed_write32(csa, state->trcconfigr, TRCCONFIGR);
1739 	etm4x_relaxed_write32(csa, state->trcauxctlr, TRCAUXCTLR);
1740 	etm4x_relaxed_write32(csa, state->trceventctl0r, TRCEVENTCTL0R);
1741 	etm4x_relaxed_write32(csa, state->trceventctl1r, TRCEVENTCTL1R);
1742 	if (drvdata->stallctl)
1743 		etm4x_relaxed_write32(csa, state->trcstallctlr, TRCSTALLCTLR);
1744 	etm4x_relaxed_write32(csa, state->trctsctlr, TRCTSCTLR);
1745 	etm4x_relaxed_write32(csa, state->trcsyncpr, TRCSYNCPR);
1746 	etm4x_relaxed_write32(csa, state->trcccctlr, TRCCCCTLR);
1747 	etm4x_relaxed_write32(csa, state->trcbbctlr, TRCBBCTLR);
1748 	etm4x_relaxed_write32(csa, state->trctraceidr, TRCTRACEIDR);
1749 	etm4x_relaxed_write32(csa, state->trcqctlr, TRCQCTLR);
1750 
1751 	etm4x_relaxed_write32(csa, state->trcvictlr, TRCVICTLR);
1752 	etm4x_relaxed_write32(csa, state->trcviiectlr, TRCVIIECTLR);
1753 	etm4x_relaxed_write32(csa, state->trcvissctlr, TRCVISSCTLR);
1754 	if (drvdata->nr_pe_cmp)
1755 		etm4x_relaxed_write32(csa, state->trcvipcssctlr, TRCVIPCSSCTLR);
1756 	etm4x_relaxed_write32(csa, state->trcvdctlr, TRCVDCTLR);
1757 	etm4x_relaxed_write32(csa, state->trcvdsacctlr, TRCVDSACCTLR);
1758 	etm4x_relaxed_write32(csa, state->trcvdarcctlr, TRCVDARCCTLR);
1759 
1760 	for (i = 0; i < drvdata->nrseqstate - 1; i++)
1761 		etm4x_relaxed_write32(csa, state->trcseqevr[i], TRCSEQEVRn(i));
1762 
1763 	etm4x_relaxed_write32(csa, state->trcseqrstevr, TRCSEQRSTEVR);
1764 	etm4x_relaxed_write32(csa, state->trcseqstr, TRCSEQSTR);
1765 	etm4x_relaxed_write32(csa, state->trcextinselr, TRCEXTINSELR);
1766 
1767 	for (i = 0; i < drvdata->nr_cntr; i++) {
1768 		etm4x_relaxed_write32(csa, state->trccntrldvr[i], TRCCNTRLDVRn(i));
1769 		etm4x_relaxed_write32(csa, state->trccntctlr[i], TRCCNTCTLRn(i));
1770 		etm4x_relaxed_write32(csa, state->trccntvr[i], TRCCNTVRn(i));
1771 	}
1772 
1773 	for (i = 0; i < drvdata->nr_resource * 2; i++)
1774 		etm4x_relaxed_write32(csa, state->trcrsctlr[i], TRCRSCTLRn(i));
1775 
1776 	for (i = 0; i < drvdata->nr_ss_cmp; i++) {
1777 		etm4x_relaxed_write32(csa, state->trcssccr[i], TRCSSCCRn(i));
1778 		etm4x_relaxed_write32(csa, state->trcsscsr[i], TRCSSCSRn(i));
1779 		if (etm4x_sspcicrn_present(drvdata, i))
1780 			etm4x_relaxed_write32(csa, state->trcsspcicr[i], TRCSSPCICRn(i));
1781 	}
1782 
1783 	for (i = 0; i < drvdata->nr_addr_cmp * 2; i++) {
1784 		etm4x_relaxed_write64(csa, state->trcacvr[i], TRCACVRn(i));
1785 		etm4x_relaxed_write64(csa, state->trcacatr[i], TRCACATRn(i));
1786 	}
1787 
1788 	for (i = 0; i < drvdata->numcidc; i++)
1789 		etm4x_relaxed_write64(csa, state->trccidcvr[i], TRCCIDCVRn(i));
1790 
1791 	for (i = 0; i < drvdata->numvmidc; i++)
1792 		etm4x_relaxed_write64(csa, state->trcvmidcvr[i], TRCVMIDCVRn(i));
1793 
1794 	etm4x_relaxed_write32(csa, state->trccidcctlr0, TRCCIDCCTLR0);
1795 	if (drvdata->numcidc > 4)
1796 		etm4x_relaxed_write32(csa, state->trccidcctlr1, TRCCIDCCTLR1);
1797 
1798 	etm4x_relaxed_write32(csa, state->trcvmidcctlr0, TRCVMIDCCTLR0);
1799 	if (drvdata->numvmidc > 4)
1800 		etm4x_relaxed_write32(csa, state->trcvmidcctlr0, TRCVMIDCCTLR1);
1801 
1802 	etm4x_relaxed_write32(csa, state->trcclaimset, TRCCLAIMSET);
1803 
1804 	if (!drvdata->skip_power_up)
1805 		etm4x_relaxed_write32(csa, state->trcpdcr, TRCPDCR);
1806 
1807 	drvdata->state_needs_restore = false;
1808 
1809 	/*
1810 	 * As recommended by section 4.3.7 ("Synchronization when using the
1811 	 * memory-mapped interface") of ARM IHI 0064D
1812 	 */
1813 	dsb(sy);
1814 	isb();
1815 
1816 	/* Unlock the OS lock to re-enable trace and external debug access */
1817 	etm4_os_unlock(drvdata);
1818 	etm4_cs_lock(drvdata, csa);
1819 }
1820 
1821 static void etm4_cpu_restore(struct etmv4_drvdata *drvdata)
1822 {
1823 	if (drvdata->trfcr)
1824 		write_trfcr(drvdata->save_trfcr);
1825 	if (drvdata->state_needs_restore)
1826 		__etm4_cpu_restore(drvdata);
1827 }
1828 
1829 static int etm4_cpu_pm_notify(struct notifier_block *nb, unsigned long cmd,
1830 			      void *v)
1831 {
1832 	struct etmv4_drvdata *drvdata;
1833 	unsigned int cpu = smp_processor_id();
1834 
1835 	if (!etmdrvdata[cpu])
1836 		return NOTIFY_OK;
1837 
1838 	drvdata = etmdrvdata[cpu];
1839 
1840 	if (WARN_ON_ONCE(drvdata->cpu != cpu))
1841 		return NOTIFY_BAD;
1842 
1843 	switch (cmd) {
1844 	case CPU_PM_ENTER:
1845 		if (etm4_cpu_save(drvdata))
1846 			return NOTIFY_BAD;
1847 		break;
1848 	case CPU_PM_EXIT:
1849 	case CPU_PM_ENTER_FAILED:
1850 		etm4_cpu_restore(drvdata);
1851 		break;
1852 	default:
1853 		return NOTIFY_DONE;
1854 	}
1855 
1856 	return NOTIFY_OK;
1857 }
1858 
1859 static struct notifier_block etm4_cpu_pm_nb = {
1860 	.notifier_call = etm4_cpu_pm_notify,
1861 };
1862 
1863 /* Setup PM. Deals with error conditions and counts */
1864 static int __init etm4_pm_setup(void)
1865 {
1866 	int ret;
1867 
1868 	ret = cpu_pm_register_notifier(&etm4_cpu_pm_nb);
1869 	if (ret)
1870 		return ret;
1871 
1872 	ret = cpuhp_setup_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING,
1873 					"arm/coresight4:starting",
1874 					etm4_starting_cpu, etm4_dying_cpu);
1875 
1876 	if (ret)
1877 		goto unregister_notifier;
1878 
1879 	ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
1880 					"arm/coresight4:online",
1881 					etm4_online_cpu, NULL);
1882 
1883 	/* HP dyn state ID returned in ret on success */
1884 	if (ret > 0) {
1885 		hp_online = ret;
1886 		return 0;
1887 	}
1888 
1889 	/* failed dyn state - remove others */
1890 	cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING);
1891 
1892 unregister_notifier:
1893 	cpu_pm_unregister_notifier(&etm4_cpu_pm_nb);
1894 	return ret;
1895 }
1896 
1897 static void etm4_pm_clear(void)
1898 {
1899 	cpu_pm_unregister_notifier(&etm4_cpu_pm_nb);
1900 	cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING);
1901 	if (hp_online) {
1902 		cpuhp_remove_state_nocalls(hp_online);
1903 		hp_online = 0;
1904 	}
1905 }
1906 
1907 static int etm4_probe(struct device *dev, void __iomem *base, u32 etm_pid)
1908 {
1909 	int ret;
1910 	struct coresight_platform_data *pdata = NULL;
1911 	struct etmv4_drvdata *drvdata;
1912 	struct coresight_desc desc = { 0 };
1913 	struct etm4_init_arg init_arg = { 0 };
1914 	u8 major, minor;
1915 	char *type_name;
1916 
1917 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
1918 	if (!drvdata)
1919 		return -ENOMEM;
1920 
1921 	dev_set_drvdata(dev, drvdata);
1922 
1923 	if (pm_save_enable == PARAM_PM_SAVE_FIRMWARE)
1924 		pm_save_enable = coresight_loses_context_with_cpu(dev) ?
1925 			       PARAM_PM_SAVE_SELF_HOSTED : PARAM_PM_SAVE_NEVER;
1926 
1927 	if (pm_save_enable != PARAM_PM_SAVE_NEVER) {
1928 		drvdata->save_state = devm_kmalloc(dev,
1929 				sizeof(struct etmv4_save_state), GFP_KERNEL);
1930 		if (!drvdata->save_state)
1931 			return -ENOMEM;
1932 	}
1933 
1934 	drvdata->base = base;
1935 
1936 	spin_lock_init(&drvdata->spinlock);
1937 
1938 	drvdata->cpu = coresight_get_cpu(dev);
1939 	if (drvdata->cpu < 0)
1940 		return drvdata->cpu;
1941 
1942 	init_arg.drvdata = drvdata;
1943 	init_arg.csa = &desc.access;
1944 	init_arg.pid = etm_pid;
1945 
1946 	if (smp_call_function_single(drvdata->cpu,
1947 				etm4_init_arch_data,  &init_arg, 1))
1948 		dev_err(dev, "ETM arch init failed\n");
1949 
1950 	if (!drvdata->arch)
1951 		return -EINVAL;
1952 
1953 	/* TRCPDCR is not accessible with system instructions. */
1954 	if (!desc.access.io_mem ||
1955 	    fwnode_property_present(dev_fwnode(dev), "qcom,skip-power-up"))
1956 		drvdata->skip_power_up = true;
1957 
1958 	major = ETM_ARCH_MAJOR_VERSION(drvdata->arch);
1959 	minor = ETM_ARCH_MINOR_VERSION(drvdata->arch);
1960 
1961 	if (etm4x_is_ete(drvdata)) {
1962 		type_name = "ete";
1963 		/* ETE v1 has major version == 0b101. Adjust this for logging.*/
1964 		major -= 4;
1965 	} else {
1966 		type_name = "etm";
1967 	}
1968 
1969 	desc.name = devm_kasprintf(dev, GFP_KERNEL,
1970 				   "%s%d", type_name, drvdata->cpu);
1971 	if (!desc.name)
1972 		return -ENOMEM;
1973 
1974 	etm4_init_trace_id(drvdata);
1975 	etm4_set_default(&drvdata->config);
1976 
1977 	pdata = coresight_get_platform_data(dev);
1978 	if (IS_ERR(pdata))
1979 		return PTR_ERR(pdata);
1980 
1981 	dev->platform_data = pdata;
1982 
1983 	desc.type = CORESIGHT_DEV_TYPE_SOURCE;
1984 	desc.subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_PROC;
1985 	desc.ops = &etm4_cs_ops;
1986 	desc.pdata = pdata;
1987 	desc.dev = dev;
1988 	desc.groups = coresight_etmv4_groups;
1989 	drvdata->csdev = coresight_register(&desc);
1990 	if (IS_ERR(drvdata->csdev))
1991 		return PTR_ERR(drvdata->csdev);
1992 
1993 	ret = etm_perf_symlink(drvdata->csdev, true);
1994 	if (ret) {
1995 		coresight_unregister(drvdata->csdev);
1996 		return ret;
1997 	}
1998 
1999 	/* register with config infrastructure & load any current features */
2000 	ret = etm4_cscfg_register(drvdata->csdev);
2001 	if (ret) {
2002 		coresight_unregister(drvdata->csdev);
2003 		return ret;
2004 	}
2005 
2006 	etmdrvdata[drvdata->cpu] = drvdata;
2007 
2008 	dev_info(&drvdata->csdev->dev, "CPU%d: %s v%d.%d initialized\n",
2009 		 drvdata->cpu, type_name, major, minor);
2010 
2011 	if (boot_enable) {
2012 		coresight_enable(drvdata->csdev);
2013 		drvdata->boot_enable = true;
2014 	}
2015 
2016 	return 0;
2017 }
2018 
2019 static int etm4_probe_amba(struct amba_device *adev, const struct amba_id *id)
2020 {
2021 	void __iomem *base;
2022 	struct device *dev = &adev->dev;
2023 	struct resource *res = &adev->res;
2024 	int ret;
2025 
2026 	/* Validity for the resource is already checked by the AMBA core */
2027 	base = devm_ioremap_resource(dev, res);
2028 	if (IS_ERR(base))
2029 		return PTR_ERR(base);
2030 
2031 	ret = etm4_probe(dev, base, id->id);
2032 	if (!ret)
2033 		pm_runtime_put(&adev->dev);
2034 
2035 	return ret;
2036 }
2037 
2038 static int etm4_probe_platform_dev(struct platform_device *pdev)
2039 {
2040 	int ret;
2041 
2042 	pm_runtime_get_noresume(&pdev->dev);
2043 	pm_runtime_set_active(&pdev->dev);
2044 	pm_runtime_enable(&pdev->dev);
2045 
2046 	/*
2047 	 * System register based devices could match the
2048 	 * HW by reading appropriate registers on the HW
2049 	 * and thus we could skip the PID.
2050 	 */
2051 	ret = etm4_probe(&pdev->dev, NULL, 0);
2052 
2053 	pm_runtime_put(&pdev->dev);
2054 	return ret;
2055 }
2056 
2057 static struct amba_cs_uci_id uci_id_etm4[] = {
2058 	{
2059 		/*  ETMv4 UCI data */
2060 		.devarch	= ETM_DEVARCH_ETMv4x_ARCH,
2061 		.devarch_mask	= ETM_DEVARCH_ID_MASK,
2062 		.devtype	= 0x00000013,
2063 	}
2064 };
2065 
2066 static void clear_etmdrvdata(void *info)
2067 {
2068 	int cpu = *(int *)info;
2069 
2070 	etmdrvdata[cpu] = NULL;
2071 }
2072 
2073 static int __exit etm4_remove_dev(struct etmv4_drvdata *drvdata)
2074 {
2075 	etm_perf_symlink(drvdata->csdev, false);
2076 	/*
2077 	 * Taking hotplug lock here to avoid racing between etm4_remove_dev()
2078 	 * and CPU hotplug call backs.
2079 	 */
2080 	cpus_read_lock();
2081 	/*
2082 	 * The readers for etmdrvdata[] are CPU hotplug call backs
2083 	 * and PM notification call backs. Change etmdrvdata[i] on
2084 	 * CPU i ensures these call backs has consistent view
2085 	 * inside one call back function.
2086 	 */
2087 	if (smp_call_function_single(drvdata->cpu, clear_etmdrvdata, &drvdata->cpu, 1))
2088 		etmdrvdata[drvdata->cpu] = NULL;
2089 
2090 	cpus_read_unlock();
2091 
2092 	cscfg_unregister_csdev(drvdata->csdev);
2093 	coresight_unregister(drvdata->csdev);
2094 
2095 	return 0;
2096 }
2097 
2098 static void __exit etm4_remove_amba(struct amba_device *adev)
2099 {
2100 	struct etmv4_drvdata *drvdata = dev_get_drvdata(&adev->dev);
2101 
2102 	if (drvdata)
2103 		etm4_remove_dev(drvdata);
2104 }
2105 
2106 static int __exit etm4_remove_platform_dev(struct platform_device *pdev)
2107 {
2108 	int ret = 0;
2109 	struct etmv4_drvdata *drvdata = dev_get_drvdata(&pdev->dev);
2110 
2111 	if (drvdata)
2112 		ret = etm4_remove_dev(drvdata);
2113 	pm_runtime_disable(&pdev->dev);
2114 	return ret;
2115 }
2116 
2117 static const struct amba_id etm4_ids[] = {
2118 	CS_AMBA_ID(0x000bb95d),			/* Cortex-A53 */
2119 	CS_AMBA_ID(0x000bb95e),			/* Cortex-A57 */
2120 	CS_AMBA_ID(0x000bb95a),			/* Cortex-A72 */
2121 	CS_AMBA_ID(0x000bb959),			/* Cortex-A73 */
2122 	CS_AMBA_UCI_ID(0x000bb9da, uci_id_etm4),/* Cortex-A35 */
2123 	CS_AMBA_UCI_ID(0x000bbd05, uci_id_etm4),/* Cortex-A55 */
2124 	CS_AMBA_UCI_ID(0x000bbd0a, uci_id_etm4),/* Cortex-A75 */
2125 	CS_AMBA_UCI_ID(0x000bbd0c, uci_id_etm4),/* Neoverse N1 */
2126 	CS_AMBA_UCI_ID(0x000bbd41, uci_id_etm4),/* Cortex-A78 */
2127 	CS_AMBA_UCI_ID(0x000f0205, uci_id_etm4),/* Qualcomm Kryo */
2128 	CS_AMBA_UCI_ID(0x000f0211, uci_id_etm4),/* Qualcomm Kryo */
2129 	CS_AMBA_UCI_ID(0x000bb802, uci_id_etm4),/* Qualcomm Kryo 385 Cortex-A55 */
2130 	CS_AMBA_UCI_ID(0x000bb803, uci_id_etm4),/* Qualcomm Kryo 385 Cortex-A75 */
2131 	CS_AMBA_UCI_ID(0x000bb805, uci_id_etm4),/* Qualcomm Kryo 4XX Cortex-A55 */
2132 	CS_AMBA_UCI_ID(0x000bb804, uci_id_etm4),/* Qualcomm Kryo 4XX Cortex-A76 */
2133 	CS_AMBA_UCI_ID(0x000bbd0d, uci_id_etm4),/* Qualcomm Kryo 5XX Cortex-A77 */
2134 	CS_AMBA_UCI_ID(0x000cc0af, uci_id_etm4),/* Marvell ThunderX2 */
2135 	CS_AMBA_UCI_ID(0x000b6d01, uci_id_etm4),/* HiSilicon-Hip08 */
2136 	CS_AMBA_UCI_ID(0x000b6d02, uci_id_etm4),/* HiSilicon-Hip09 */
2137 	{},
2138 };
2139 
2140 MODULE_DEVICE_TABLE(amba, etm4_ids);
2141 
2142 static struct amba_driver etm4x_amba_driver = {
2143 	.drv = {
2144 		.name   = "coresight-etm4x",
2145 		.owner  = THIS_MODULE,
2146 		.suppress_bind_attrs = true,
2147 	},
2148 	.probe		= etm4_probe_amba,
2149 	.remove         = etm4_remove_amba,
2150 	.id_table	= etm4_ids,
2151 };
2152 
2153 static const struct of_device_id etm4_sysreg_match[] = {
2154 	{ .compatible	= "arm,coresight-etm4x-sysreg" },
2155 	{ .compatible	= "arm,embedded-trace-extension" },
2156 	{}
2157 };
2158 
2159 static struct platform_driver etm4_platform_driver = {
2160 	.probe		= etm4_probe_platform_dev,
2161 	.remove		= etm4_remove_platform_dev,
2162 	.driver			= {
2163 		.name			= "coresight-etm4x",
2164 		.of_match_table		= etm4_sysreg_match,
2165 		.suppress_bind_attrs	= true,
2166 	},
2167 };
2168 
2169 static int __init etm4x_init(void)
2170 {
2171 	int ret;
2172 
2173 	ret = etm4_pm_setup();
2174 
2175 	/* etm4_pm_setup() does its own cleanup - exit on error */
2176 	if (ret)
2177 		return ret;
2178 
2179 	ret = amba_driver_register(&etm4x_amba_driver);
2180 	if (ret) {
2181 		pr_err("Error registering etm4x AMBA driver\n");
2182 		goto clear_pm;
2183 	}
2184 
2185 	ret = platform_driver_register(&etm4_platform_driver);
2186 	if (!ret)
2187 		return 0;
2188 
2189 	pr_err("Error registering etm4x platform driver\n");
2190 	amba_driver_unregister(&etm4x_amba_driver);
2191 
2192 clear_pm:
2193 	etm4_pm_clear();
2194 	return ret;
2195 }
2196 
2197 static void __exit etm4x_exit(void)
2198 {
2199 	amba_driver_unregister(&etm4x_amba_driver);
2200 	platform_driver_unregister(&etm4_platform_driver);
2201 	etm4_pm_clear();
2202 }
2203 
2204 module_init(etm4x_init);
2205 module_exit(etm4x_exit);
2206 
2207 MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>");
2208 MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@linaro.org>");
2209 MODULE_DESCRIPTION("Arm CoreSight Program Flow Trace v4.x driver");
2210 MODULE_LICENSE("GPL v2");
2211