xref: /OK3568_Linux_fs/kernel/drivers/hwtracing/coresight/coresight-etm4x-core.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
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-self-hosted-trace.h"
43 
44 static int boot_enable;
45 module_param(boot_enable, int, 0444);
46 MODULE_PARM_DESC(boot_enable, "Enable tracing on boot");
47 
48 #define PARAM_PM_SAVE_FIRMWARE	  0 /* save self-hosted state as per firmware */
49 #define PARAM_PM_SAVE_NEVER	  1 /* never save any state */
50 #define PARAM_PM_SAVE_SELF_HOSTED 2 /* save self-hosted state only */
51 
52 static int pm_save_enable = PARAM_PM_SAVE_FIRMWARE;
53 module_param(pm_save_enable, int, 0444);
54 MODULE_PARM_DESC(pm_save_enable,
55 	"Save/restore state on power down: 1 = never, 2 = self-hosted");
56 
57 static struct etmv4_drvdata *etmdrvdata[NR_CPUS];
58 static void etm4_set_default_config(struct etmv4_config *config);
59 static int etm4_set_event_filters(struct etmv4_drvdata *drvdata,
60 				  struct perf_event *event);
61 static u64 etm4_get_access_type(struct etmv4_config *config);
62 
63 static enum cpuhp_state hp_online;
64 
65 struct etm4_init_arg {
66 	unsigned int		pid;
67 	struct etmv4_drvdata	*drvdata;
68 	struct csdev_access	*csa;
69 };
70 
71 /*
72  * Check if TRCSSPCICRn(i) is implemented for a given instance.
73  *
74  * TRCSSPCICRn is implemented only if :
75  *	TRCSSPCICR<n> is present only if all of the following are true:
76  *		TRCIDR4.NUMSSCC > n.
77  *		TRCIDR4.NUMPC > 0b0000 .
78  *		TRCSSCSR<n>.PC == 0b1
79  */
etm4x_sspcicrn_present(struct etmv4_drvdata * drvdata,int n)80 static inline bool etm4x_sspcicrn_present(struct etmv4_drvdata *drvdata, int n)
81 {
82 	return (n < drvdata->nr_ss_cmp) &&
83 	       drvdata->nr_pe &&
84 	       (drvdata->config.ss_status[n] & TRCSSCSRn_PC);
85 }
86 
etm4x_sysreg_read(u32 offset,bool _relaxed,bool _64bit)87 u64 etm4x_sysreg_read(u32 offset, bool _relaxed, bool _64bit)
88 {
89 	u64 res = 0;
90 
91 	switch (offset) {
92 	ETM4x_READ_SYSREG_CASES(res)
93 	default :
94 		pr_warn_ratelimited("etm4x: trying to read unsupported register @%x\n",
95 			 offset);
96 	}
97 
98 	if (!_relaxed)
99 		__iormb(res);	/* Imitate the !relaxed I/O helpers */
100 
101 	return res;
102 }
103 
etm4x_sysreg_write(u64 val,u32 offset,bool _relaxed,bool _64bit)104 void etm4x_sysreg_write(u64 val, u32 offset, bool _relaxed, bool _64bit)
105 {
106 	if (!_relaxed)
107 		__iowmb();	/* Imitate the !relaxed I/O helpers */
108 	if (!_64bit)
109 		val &= GENMASK(31, 0);
110 
111 	switch (offset) {
112 	ETM4x_WRITE_SYSREG_CASES(val)
113 	default :
114 		pr_warn_ratelimited("etm4x: trying to write to unsupported register @%x\n",
115 			offset);
116 	}
117 }
118 
ete_sysreg_read(u32 offset,bool _relaxed,bool _64bit)119 static u64 ete_sysreg_read(u32 offset, bool _relaxed, bool _64bit)
120 {
121 	u64 res = 0;
122 
123 	switch (offset) {
124 	ETE_READ_CASES(res)
125 	default :
126 		pr_warn_ratelimited("ete: trying to read unsupported register @%x\n",
127 				    offset);
128 	}
129 
130 	if (!_relaxed)
131 		__iormb(res);	/* Imitate the !relaxed I/O helpers */
132 
133 	return res;
134 }
135 
ete_sysreg_write(u64 val,u32 offset,bool _relaxed,bool _64bit)136 static void ete_sysreg_write(u64 val, u32 offset, bool _relaxed, bool _64bit)
137 {
138 	if (!_relaxed)
139 		__iowmb();	/* Imitate the !relaxed I/O helpers */
140 	if (!_64bit)
141 		val &= GENMASK(31, 0);
142 
143 	switch (offset) {
144 	ETE_WRITE_CASES(val)
145 	default :
146 		pr_warn_ratelimited("ete: trying to write to unsupported register @%x\n",
147 				    offset);
148 	}
149 }
150 
etm_detect_os_lock(struct etmv4_drvdata * drvdata,struct csdev_access * csa)151 static void etm_detect_os_lock(struct etmv4_drvdata *drvdata,
152 			       struct csdev_access *csa)
153 {
154 	u32 oslsr = etm4x_relaxed_read32(csa, TRCOSLSR);
155 
156 	drvdata->os_lock_model = ETM_OSLSR_OSLM(oslsr);
157 }
158 
etm_write_os_lock(struct etmv4_drvdata * drvdata,struct csdev_access * csa,u32 val)159 static void etm_write_os_lock(struct etmv4_drvdata *drvdata,
160 			      struct csdev_access *csa, u32 val)
161 {
162 	val = !!val;
163 
164 	switch (drvdata->os_lock_model) {
165 	case ETM_OSLOCK_PRESENT:
166 		etm4x_relaxed_write32(csa, val, TRCOSLAR);
167 		break;
168 	case ETM_OSLOCK_PE:
169 		write_sysreg_s(val, SYS_OSLAR_EL1);
170 		break;
171 	default:
172 		pr_warn_once("CPU%d: Unsupported Trace OSLock model: %x\n",
173 			     smp_processor_id(), drvdata->os_lock_model);
174 		fallthrough;
175 	case ETM_OSLOCK_NI:
176 		return;
177 	}
178 	isb();
179 }
180 
etm4_os_unlock_csa(struct etmv4_drvdata * drvdata,struct csdev_access * csa)181 static inline void etm4_os_unlock_csa(struct etmv4_drvdata *drvdata,
182 				      struct csdev_access *csa)
183 {
184 	WARN_ON(drvdata->cpu != smp_processor_id());
185 
186 	/* Writing 0 to OS Lock unlocks the trace unit registers */
187 	etm_write_os_lock(drvdata, csa, 0x0);
188 	drvdata->os_unlock = true;
189 }
190 
etm4_os_unlock(struct etmv4_drvdata * drvdata)191 static void etm4_os_unlock(struct etmv4_drvdata *drvdata)
192 {
193 	if (!WARN_ON(!drvdata->csdev))
194 		etm4_os_unlock_csa(drvdata, &drvdata->csdev->access);
195 }
196 
etm4_os_lock(struct etmv4_drvdata * drvdata)197 static void etm4_os_lock(struct etmv4_drvdata *drvdata)
198 {
199 	if (WARN_ON(!drvdata->csdev))
200 		return;
201 	/* Writing 0x1 to OS Lock locks the trace registers */
202 	etm_write_os_lock(drvdata, &drvdata->csdev->access, 0x1);
203 	drvdata->os_unlock = false;
204 }
205 
etm4_cs_lock(struct etmv4_drvdata * drvdata,struct csdev_access * csa)206 static void etm4_cs_lock(struct etmv4_drvdata *drvdata,
207 			 struct csdev_access *csa)
208 {
209 	/* Software Lock is only accessible via memory mapped interface */
210 	if (csa->io_mem)
211 		CS_LOCK(csa->base);
212 }
213 
etm4_cs_unlock(struct etmv4_drvdata * drvdata,struct csdev_access * csa)214 static void etm4_cs_unlock(struct etmv4_drvdata *drvdata,
215 			   struct csdev_access *csa)
216 {
217 	if (csa->io_mem)
218 		CS_UNLOCK(csa->base);
219 }
220 
etm4_cpu_id(struct coresight_device * csdev)221 static int etm4_cpu_id(struct coresight_device *csdev)
222 {
223 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
224 
225 	return drvdata->cpu;
226 }
227 
etm4_trace_id(struct coresight_device * csdev)228 static int etm4_trace_id(struct coresight_device *csdev)
229 {
230 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
231 
232 	return drvdata->trcid;
233 }
234 
235 struct etm4_enable_arg {
236 	struct etmv4_drvdata *drvdata;
237 	int rc;
238 };
239 
240 /*
241  * etm4x_prohibit_trace - Prohibit the CPU from tracing at all ELs.
242  * When the CPU supports FEAT_TRF, we could move the ETM to a trace
243  * prohibited state by filtering the Exception levels via TRFCR_EL1.
244  */
etm4x_prohibit_trace(struct etmv4_drvdata * drvdata)245 static void etm4x_prohibit_trace(struct etmv4_drvdata *drvdata)
246 {
247 	/* If the CPU doesn't support FEAT_TRF, nothing to do */
248 	if (!drvdata->trfcr)
249 		return;
250 	cpu_prohibit_trace();
251 }
252 
253 /*
254  * etm4x_allow_trace - Allow CPU tracing in the respective ELs,
255  * as configured by the drvdata->config.mode for the current
256  * session. Even though we have TRCVICTLR bits to filter the
257  * trace in the ELs, it doesn't prevent the ETM from generating
258  * a packet (e.g, TraceInfo) that might contain the addresses from
259  * the excluded levels. Thus we use the additional controls provided
260  * via the Trace Filtering controls (FEAT_TRF) to make sure no trace
261  * is generated for the excluded ELs.
262  */
etm4x_allow_trace(struct etmv4_drvdata * drvdata)263 static void etm4x_allow_trace(struct etmv4_drvdata *drvdata)
264 {
265 	u64 trfcr = drvdata->trfcr;
266 
267 	/* If the CPU doesn't support FEAT_TRF, nothing to do */
268 	if (!trfcr)
269 		return;
270 
271 	if (drvdata->config.mode & ETM_MODE_EXCL_KERN)
272 		trfcr &= ~TRFCR_ELx_ExTRE;
273 	if (drvdata->config.mode & ETM_MODE_EXCL_USER)
274 		trfcr &= ~TRFCR_ELx_E0TRE;
275 
276 	write_trfcr(trfcr);
277 }
278 
279 #ifdef CONFIG_ETM4X_IMPDEF_FEATURE
280 
281 #define HISI_HIP08_AMBA_ID		0x000b6d01
282 #define ETM4_AMBA_MASK			0xfffff
283 #define HISI_HIP08_CORE_COMMIT_MASK	0x3000
284 #define HISI_HIP08_CORE_COMMIT_SHIFT	12
285 #define HISI_HIP08_CORE_COMMIT_FULL	0b00
286 #define HISI_HIP08_CORE_COMMIT_LVL_1	0b01
287 #define HISI_HIP08_CORE_COMMIT_REG	sys_reg(3, 1, 15, 2, 5)
288 
289 struct etm4_arch_features {
290 	void (*arch_callback)(bool enable);
291 };
292 
etm4_hisi_match_pid(unsigned int id)293 static bool etm4_hisi_match_pid(unsigned int id)
294 {
295 	return (id & ETM4_AMBA_MASK) == HISI_HIP08_AMBA_ID;
296 }
297 
etm4_hisi_config_core_commit(bool enable)298 static void etm4_hisi_config_core_commit(bool enable)
299 {
300 	u8 commit = enable ? HISI_HIP08_CORE_COMMIT_LVL_1 :
301 		    HISI_HIP08_CORE_COMMIT_FULL;
302 	u64 val;
303 
304 	/*
305 	 * bit 12 and 13 of HISI_HIP08_CORE_COMMIT_REG are used together
306 	 * to set core-commit, 2'b00 means cpu is at full speed, 2'b01,
307 	 * 2'b10, 2'b11 mean reduce pipeline speed, and 2'b01 means level-1
308 	 * speed(minimun value). So bit 12 and 13 should be cleared together.
309 	 */
310 	val = read_sysreg_s(HISI_HIP08_CORE_COMMIT_REG);
311 	val &= ~HISI_HIP08_CORE_COMMIT_MASK;
312 	val |= commit << HISI_HIP08_CORE_COMMIT_SHIFT;
313 	write_sysreg_s(val, HISI_HIP08_CORE_COMMIT_REG);
314 }
315 
316 static struct etm4_arch_features etm4_features[] = {
317 	[ETM4_IMPDEF_HISI_CORE_COMMIT] = {
318 		.arch_callback = etm4_hisi_config_core_commit,
319 	},
320 	{},
321 };
322 
etm4_enable_arch_specific(struct etmv4_drvdata * drvdata)323 static void etm4_enable_arch_specific(struct etmv4_drvdata *drvdata)
324 {
325 	struct etm4_arch_features *ftr;
326 	int bit;
327 
328 	for_each_set_bit(bit, drvdata->arch_features, ETM4_IMPDEF_FEATURE_MAX) {
329 		ftr = &etm4_features[bit];
330 
331 		if (ftr->arch_callback)
332 			ftr->arch_callback(true);
333 	}
334 }
335 
etm4_disable_arch_specific(struct etmv4_drvdata * drvdata)336 static void etm4_disable_arch_specific(struct etmv4_drvdata *drvdata)
337 {
338 	struct etm4_arch_features *ftr;
339 	int bit;
340 
341 	for_each_set_bit(bit, drvdata->arch_features, ETM4_IMPDEF_FEATURE_MAX) {
342 		ftr = &etm4_features[bit];
343 
344 		if (ftr->arch_callback)
345 			ftr->arch_callback(false);
346 	}
347 }
348 
etm4_check_arch_features(struct etmv4_drvdata * drvdata,unsigned int id)349 static void etm4_check_arch_features(struct etmv4_drvdata *drvdata,
350 				      unsigned int id)
351 {
352 	if (etm4_hisi_match_pid(id))
353 		set_bit(ETM4_IMPDEF_HISI_CORE_COMMIT, drvdata->arch_features);
354 }
355 #else
etm4_enable_arch_specific(struct etmv4_drvdata * drvdata)356 static void etm4_enable_arch_specific(struct etmv4_drvdata *drvdata)
357 {
358 }
359 
etm4_disable_arch_specific(struct etmv4_drvdata * drvdata)360 static void etm4_disable_arch_specific(struct etmv4_drvdata *drvdata)
361 {
362 }
363 
etm4_check_arch_features(struct etmv4_drvdata * drvdata,unsigned int id)364 static void etm4_check_arch_features(struct etmv4_drvdata *drvdata,
365 				     unsigned int id)
366 {
367 }
368 #endif /* CONFIG_ETM4X_IMPDEF_FEATURE */
369 
etm4_enable_hw(struct etmv4_drvdata * drvdata)370 static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
371 {
372 	int i, rc;
373 	struct etmv4_config *config = &drvdata->config;
374 	struct coresight_device *csdev = drvdata->csdev;
375 	struct device *etm_dev = &csdev->dev;
376 	struct csdev_access *csa = &csdev->access;
377 
378 
379 	etm4_cs_unlock(drvdata, csa);
380 	etm4_enable_arch_specific(drvdata);
381 
382 	etm4_os_unlock(drvdata);
383 
384 	rc = coresight_claim_device_unlocked(csdev);
385 	if (rc)
386 		goto done;
387 
388 	/* Disable the trace unit before programming trace registers */
389 	etm4x_relaxed_write32(csa, 0, TRCPRGCTLR);
390 
391 	/*
392 	 * If we use system instructions, we need to synchronize the
393 	 * write to the TRCPRGCTLR, before accessing the TRCSTATR.
394 	 * See ARM IHI0064F, section
395 	 * "4.3.7 Synchronization of register updates"
396 	 */
397 	if (!csa->io_mem)
398 		isb();
399 
400 	/* wait for TRCSTATR.IDLE to go up */
401 	if (coresight_timeout(csa, TRCSTATR, TRCSTATR_IDLE_BIT, 1))
402 		dev_err(etm_dev,
403 			"timeout while waiting for Idle Trace Status\n");
404 	if (drvdata->nr_pe)
405 		etm4x_relaxed_write32(csa, config->pe_sel, TRCPROCSELR);
406 	etm4x_relaxed_write32(csa, config->cfg, TRCCONFIGR);
407 	/* nothing specific implemented */
408 	etm4x_relaxed_write32(csa, 0x0, TRCAUXCTLR);
409 	etm4x_relaxed_write32(csa, config->eventctrl0, TRCEVENTCTL0R);
410 	etm4x_relaxed_write32(csa, config->eventctrl1, TRCEVENTCTL1R);
411 	if (drvdata->stallctl)
412 		etm4x_relaxed_write32(csa, config->stall_ctrl, TRCSTALLCTLR);
413 	etm4x_relaxed_write32(csa, config->ts_ctrl, TRCTSCTLR);
414 	etm4x_relaxed_write32(csa, config->syncfreq, TRCSYNCPR);
415 	etm4x_relaxed_write32(csa, config->ccctlr, TRCCCCTLR);
416 	etm4x_relaxed_write32(csa, config->bb_ctrl, TRCBBCTLR);
417 	etm4x_relaxed_write32(csa, drvdata->trcid, TRCTRACEIDR);
418 	etm4x_relaxed_write32(csa, config->vinst_ctrl, TRCVICTLR);
419 	etm4x_relaxed_write32(csa, config->viiectlr, TRCVIIECTLR);
420 	etm4x_relaxed_write32(csa, config->vissctlr, TRCVISSCTLR);
421 	if (drvdata->nr_pe_cmp)
422 		etm4x_relaxed_write32(csa, config->vipcssctlr, TRCVIPCSSCTLR);
423 	for (i = 0; i < drvdata->nrseqstate - 1; i++)
424 		etm4x_relaxed_write32(csa, config->seq_ctrl[i], TRCSEQEVRn(i));
425 	etm4x_relaxed_write32(csa, config->seq_rst, TRCSEQRSTEVR);
426 	etm4x_relaxed_write32(csa, config->seq_state, TRCSEQSTR);
427 	etm4x_relaxed_write32(csa, config->ext_inp, TRCEXTINSELR);
428 	for (i = 0; i < drvdata->nr_cntr; i++) {
429 		etm4x_relaxed_write32(csa, config->cntrldvr[i], TRCCNTRLDVRn(i));
430 		etm4x_relaxed_write32(csa, config->cntr_ctrl[i], TRCCNTCTLRn(i));
431 		etm4x_relaxed_write32(csa, config->cntr_val[i], TRCCNTVRn(i));
432 	}
433 
434 	/*
435 	 * Resource selector pair 0 is always implemented and reserved.  As
436 	 * such start at 2.
437 	 */
438 	for (i = 2; i < drvdata->nr_resource * 2; i++)
439 		etm4x_relaxed_write32(csa, config->res_ctrl[i], TRCRSCTLRn(i));
440 
441 	for (i = 0; i < drvdata->nr_ss_cmp; i++) {
442 		/* always clear status bit on restart if using single-shot */
443 		if (config->ss_ctrl[i] || config->ss_pe_cmp[i])
444 			config->ss_status[i] &= ~BIT(31);
445 		etm4x_relaxed_write32(csa, config->ss_ctrl[i], TRCSSCCRn(i));
446 		etm4x_relaxed_write32(csa, config->ss_status[i], TRCSSCSRn(i));
447 		if (etm4x_sspcicrn_present(drvdata, i))
448 			etm4x_relaxed_write32(csa, config->ss_pe_cmp[i], TRCSSPCICRn(i));
449 	}
450 	for (i = 0; i < drvdata->nr_addr_cmp; i++) {
451 		etm4x_relaxed_write64(csa, config->addr_val[i], TRCACVRn(i));
452 		etm4x_relaxed_write64(csa, config->addr_acc[i], TRCACATRn(i));
453 	}
454 	for (i = 0; i < drvdata->numcidc; i++)
455 		etm4x_relaxed_write64(csa, config->ctxid_pid[i], TRCCIDCVRn(i));
456 	etm4x_relaxed_write32(csa, config->ctxid_mask0, TRCCIDCCTLR0);
457 	if (drvdata->numcidc > 4)
458 		etm4x_relaxed_write32(csa, config->ctxid_mask1, TRCCIDCCTLR1);
459 
460 	for (i = 0; i < drvdata->numvmidc; i++)
461 		etm4x_relaxed_write64(csa, config->vmid_val[i], TRCVMIDCVRn(i));
462 	etm4x_relaxed_write32(csa, config->vmid_mask0, TRCVMIDCCTLR0);
463 	if (drvdata->numvmidc > 4)
464 		etm4x_relaxed_write32(csa, config->vmid_mask1, TRCVMIDCCTLR1);
465 
466 	if (!drvdata->skip_power_up) {
467 		u32 trcpdcr = etm4x_relaxed_read32(csa, TRCPDCR);
468 
469 		/*
470 		 * Request to keep the trace unit powered and also
471 		 * emulation of powerdown
472 		 */
473 		etm4x_relaxed_write32(csa, trcpdcr | TRCPDCR_PU, TRCPDCR);
474 	}
475 
476 	/*
477 	 * ETE mandates that the TRCRSR is written to before
478 	 * enabling it.
479 	 */
480 	if (etm4x_is_ete(drvdata))
481 		etm4x_relaxed_write32(csa, TRCRSR_TA, TRCRSR);
482 
483 	etm4x_allow_trace(drvdata);
484 	/* Enable the trace unit */
485 	etm4x_relaxed_write32(csa, 1, TRCPRGCTLR);
486 
487 	/* Synchronize the register updates for sysreg access */
488 	if (!csa->io_mem)
489 		isb();
490 
491 	/* wait for TRCSTATR.IDLE to go back down to '0' */
492 	if (coresight_timeout(csa, TRCSTATR, TRCSTATR_IDLE_BIT, 0))
493 		dev_err(etm_dev,
494 			"timeout while waiting for Idle Trace Status\n");
495 
496 	/*
497 	 * As recommended by section 4.3.7 ("Synchronization when using the
498 	 * memory-mapped interface") of ARM IHI 0064D
499 	 */
500 	dsb(sy);
501 	isb();
502 
503 done:
504 	etm4_cs_lock(drvdata, csa);
505 
506 	dev_dbg(etm_dev, "cpu: %d enable smp call done: %d\n",
507 		drvdata->cpu, rc);
508 	return rc;
509 }
510 
etm4_enable_hw_smp_call(void * info)511 static void etm4_enable_hw_smp_call(void *info)
512 {
513 	struct etm4_enable_arg *arg = info;
514 
515 	if (WARN_ON(!arg))
516 		return;
517 	arg->rc = etm4_enable_hw(arg->drvdata);
518 }
519 
520 /*
521  * The goal of function etm4_config_timestamp_event() is to configure a
522  * counter that will tell the tracer to emit a timestamp packet when it
523  * reaches zero.  This is done in order to get a more fine grained idea
524  * of when instructions are executed so that they can be correlated
525  * with execution on other CPUs.
526  *
527  * To do this the counter itself is configured to self reload and
528  * TRCRSCTLR1 (always true) used to get the counter to decrement.  From
529  * there a resource selector is configured with the counter and the
530  * timestamp control register to use the resource selector to trigger the
531  * event that will insert a timestamp packet in the stream.
532  */
etm4_config_timestamp_event(struct etmv4_drvdata * drvdata)533 static int etm4_config_timestamp_event(struct etmv4_drvdata *drvdata)
534 {
535 	int ctridx, ret = -EINVAL;
536 	int counter, rselector;
537 	u32 val = 0;
538 	struct etmv4_config *config = &drvdata->config;
539 
540 	/* No point in trying if we don't have at least one counter */
541 	if (!drvdata->nr_cntr)
542 		goto out;
543 
544 	/* Find a counter that hasn't been initialised */
545 	for (ctridx = 0; ctridx < drvdata->nr_cntr; ctridx++)
546 		if (config->cntr_val[ctridx] == 0)
547 			break;
548 
549 	/* All the counters have been configured already, bail out */
550 	if (ctridx == drvdata->nr_cntr) {
551 		pr_debug("%s: no available counter found\n", __func__);
552 		ret = -ENOSPC;
553 		goto out;
554 	}
555 
556 	/*
557 	 * Searching for an available resource selector to use, starting at
558 	 * '2' since every implementation has at least 2 resource selector.
559 	 * ETMIDR4 gives the number of resource selector _pairs_,
560 	 * hence multiply by 2.
561 	 */
562 	for (rselector = 2; rselector < drvdata->nr_resource * 2; rselector++)
563 		if (!config->res_ctrl[rselector])
564 			break;
565 
566 	if (rselector == drvdata->nr_resource * 2) {
567 		pr_debug("%s: no available resource selector found\n",
568 			 __func__);
569 		ret = -ENOSPC;
570 		goto out;
571 	}
572 
573 	/* Remember what counter we used */
574 	counter = 1 << ctridx;
575 
576 	/*
577 	 * Initialise original and reload counter value to the smallest
578 	 * possible value in order to get as much precision as we can.
579 	 */
580 	config->cntr_val[ctridx] = 1;
581 	config->cntrldvr[ctridx] = 1;
582 
583 	/* Set the trace counter control register */
584 	val =  0x1 << 16	|  /* Bit 16, reload counter automatically */
585 	       0x0 << 7		|  /* Select single resource selector */
586 	       0x1;		   /* Resource selector 1, i.e always true */
587 
588 	config->cntr_ctrl[ctridx] = val;
589 
590 	val = 0x2 << 16		| /* Group 0b0010 - Counter and sequencers */
591 	      counter << 0;	  /* Counter to use */
592 
593 	config->res_ctrl[rselector] = val;
594 
595 	val = 0x0 << 7		| /* Select single resource selector */
596 	      rselector;	  /* Resource selector */
597 
598 	config->ts_ctrl = val;
599 
600 	ret = 0;
601 out:
602 	return ret;
603 }
604 
etm4_parse_event_config(struct etmv4_drvdata * drvdata,struct perf_event * event)605 static int etm4_parse_event_config(struct etmv4_drvdata *drvdata,
606 				   struct perf_event *event)
607 {
608 	int ret = 0;
609 	struct etmv4_config *config = &drvdata->config;
610 	struct perf_event_attr *attr = &event->attr;
611 
612 	if (!attr) {
613 		ret = -EINVAL;
614 		goto out;
615 	}
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 |= BIT(4);
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 |= BIT(11);
657 	}
658 
659 	if (attr->config & BIT(ETM_OPT_CTXTID))
660 		/* bit[6], Context ID tracing bit */
661 		config->cfg |= BIT(ETM4_CFG_BIT_CTXTID);
662 
663 	/*
664 	 * If set bit ETM_OPT_CTXTID2 in perf config, this asks to trace VMID
665 	 * for recording CONTEXTIDR_EL2.  Do not enable VMID tracing if the
666 	 * kernel is not running in EL2.
667 	 */
668 	if (attr->config & BIT(ETM_OPT_CTXTID2)) {
669 		if (!is_kernel_in_hyp_mode()) {
670 			ret = -EINVAL;
671 			goto out;
672 		}
673 		config->cfg |= BIT(ETM4_CFG_BIT_VMID) | BIT(ETM4_CFG_BIT_VMID_OPT);
674 	}
675 
676 	/* return stack - enable if selected and supported */
677 	if ((attr->config & BIT(ETM_OPT_RETSTK)) && drvdata->retstack)
678 		/* bit[12], Return stack enable bit */
679 		config->cfg |= BIT(12);
680 
681 out:
682 	return ret;
683 }
684 
etm4_enable_perf(struct coresight_device * csdev,struct perf_event * event)685 static int etm4_enable_perf(struct coresight_device *csdev,
686 			    struct perf_event *event)
687 {
688 	int ret = 0;
689 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
690 
691 	if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id())) {
692 		ret = -EINVAL;
693 		goto out;
694 	}
695 
696 	/* Configure the tracer based on the session's specifics */
697 	ret = etm4_parse_event_config(drvdata, event);
698 	if (ret)
699 		goto out;
700 	/* And enable it */
701 	ret = etm4_enable_hw(drvdata);
702 
703 out:
704 	return ret;
705 }
706 
etm4_enable_sysfs(struct coresight_device * csdev)707 static int etm4_enable_sysfs(struct coresight_device *csdev)
708 {
709 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
710 	struct etm4_enable_arg arg = { };
711 	int ret;
712 
713 	spin_lock(&drvdata->spinlock);
714 
715 	/*
716 	 * Executing etm4_enable_hw on the cpu whose ETM is being enabled
717 	 * ensures that register writes occur when cpu is powered.
718 	 */
719 	arg.drvdata = drvdata;
720 	ret = smp_call_function_single(drvdata->cpu,
721 				       etm4_enable_hw_smp_call, &arg, 1);
722 	if (!ret)
723 		ret = arg.rc;
724 	if (!ret)
725 		drvdata->sticky_enable = true;
726 	spin_unlock(&drvdata->spinlock);
727 
728 	if (!ret)
729 		dev_dbg(&csdev->dev, "ETM tracing enabled\n");
730 	return ret;
731 }
732 
etm4_enable(struct coresight_device * csdev,struct perf_event * event,u32 mode)733 static int etm4_enable(struct coresight_device *csdev,
734 		       struct perf_event *event, u32 mode)
735 {
736 	int ret;
737 	u32 val;
738 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
739 
740 	val = local_cmpxchg(&drvdata->mode, CS_MODE_DISABLED, mode);
741 
742 	/* Someone is already using the tracer */
743 	if (val)
744 		return -EBUSY;
745 
746 	switch (mode) {
747 	case CS_MODE_SYSFS:
748 		ret = etm4_enable_sysfs(csdev);
749 		break;
750 	case CS_MODE_PERF:
751 		ret = etm4_enable_perf(csdev, event);
752 		break;
753 	default:
754 		ret = -EINVAL;
755 	}
756 
757 	/* The tracer didn't start */
758 	if (ret)
759 		local_set(&drvdata->mode, CS_MODE_DISABLED);
760 
761 	return ret;
762 }
763 
etm4_disable_hw(void * info)764 static void etm4_disable_hw(void *info)
765 {
766 	u32 control;
767 	struct etmv4_drvdata *drvdata = info;
768 	struct etmv4_config *config = &drvdata->config;
769 	struct coresight_device *csdev = drvdata->csdev;
770 	struct device *etm_dev = &csdev->dev;
771 	struct csdev_access *csa = &csdev->access;
772 	int i;
773 
774 	etm4_cs_unlock(drvdata, csa);
775 	etm4_disable_arch_specific(drvdata);
776 
777 	if (!drvdata->skip_power_up) {
778 		/* power can be removed from the trace unit now */
779 		control = etm4x_relaxed_read32(csa, TRCPDCR);
780 		control &= ~TRCPDCR_PU;
781 		etm4x_relaxed_write32(csa, control, TRCPDCR);
782 	}
783 
784 	control = etm4x_relaxed_read32(csa, TRCPRGCTLR);
785 
786 	/* EN, bit[0] Trace unit enable bit */
787 	control &= ~0x1;
788 
789 	/*
790 	 * If the CPU supports v8.4 Trace filter Control,
791 	 * set the ETM to trace prohibited region.
792 	 */
793 	etm4x_prohibit_trace(drvdata);
794 	/*
795 	 * Make sure everything completes before disabling, as recommended
796 	 * by section 7.3.77 ("TRCVICTLR, ViewInst Main Control Register,
797 	 * SSTATUS") of ARM IHI 0064D
798 	 */
799 	dsb(sy);
800 	isb();
801 	/* Trace synchronization barrier, is a nop if not supported */
802 	tsb_csync();
803 	etm4x_relaxed_write32(csa, control, TRCPRGCTLR);
804 
805 	/* wait for TRCSTATR.PMSTABLE to go to '1' */
806 	if (coresight_timeout(csa, TRCSTATR, TRCSTATR_PMSTABLE_BIT, 1))
807 		dev_err(etm_dev,
808 			"timeout while waiting for PM stable Trace Status\n");
809 	/* read the status of the single shot comparators */
810 	for (i = 0; i < drvdata->nr_ss_cmp; i++) {
811 		config->ss_status[i] =
812 			etm4x_relaxed_read32(csa, TRCSSCSRn(i));
813 	}
814 
815 	/* read back the current counter values */
816 	for (i = 0; i < drvdata->nr_cntr; i++) {
817 		config->cntr_val[i] =
818 			etm4x_relaxed_read32(csa, TRCCNTVRn(i));
819 	}
820 
821 	coresight_disclaim_device_unlocked(csdev);
822 	etm4_cs_lock(drvdata, csa);
823 
824 	dev_dbg(&drvdata->csdev->dev,
825 		"cpu: %d disable smp call done\n", drvdata->cpu);
826 }
827 
etm4_disable_perf(struct coresight_device * csdev,struct perf_event * event)828 static int etm4_disable_perf(struct coresight_device *csdev,
829 			     struct perf_event *event)
830 {
831 	u32 control;
832 	struct etm_filters *filters = event->hw.addr_filters;
833 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
834 
835 	if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id()))
836 		return -EINVAL;
837 
838 	etm4_disable_hw(drvdata);
839 
840 	/*
841 	 * Check if the start/stop logic was active when the unit was stopped.
842 	 * That way we can re-enable the start/stop logic when the process is
843 	 * scheduled again.  Configuration of the start/stop logic happens in
844 	 * function etm4_set_event_filters().
845 	 */
846 	control = etm4x_relaxed_read32(&csdev->access, TRCVICTLR);
847 	/* TRCVICTLR::SSSTATUS, bit[9] */
848 	filters->ssstatus = (control & BIT(9));
849 
850 	return 0;
851 }
852 
etm4_disable_sysfs(struct coresight_device * csdev)853 static void etm4_disable_sysfs(struct coresight_device *csdev)
854 {
855 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
856 
857 	/*
858 	 * Taking hotplug lock here protects from clocks getting disabled
859 	 * with tracing being left on (crash scenario) if user disable occurs
860 	 * after cpu online mask indicates the cpu is offline but before the
861 	 * DYING hotplug callback is serviced by the ETM driver.
862 	 */
863 	cpus_read_lock();
864 	spin_lock(&drvdata->spinlock);
865 
866 	/*
867 	 * Executing etm4_disable_hw on the cpu whose ETM is being disabled
868 	 * ensures that register writes occur when cpu is powered.
869 	 */
870 	smp_call_function_single(drvdata->cpu, etm4_disable_hw, drvdata, 1);
871 
872 	spin_unlock(&drvdata->spinlock);
873 	cpus_read_unlock();
874 
875 	dev_dbg(&csdev->dev, "ETM tracing disabled\n");
876 }
877 
etm4_disable(struct coresight_device * csdev,struct perf_event * event)878 static void etm4_disable(struct coresight_device *csdev,
879 			 struct perf_event *event)
880 {
881 	u32 mode;
882 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
883 
884 	/*
885 	 * For as long as the tracer isn't disabled another entity can't
886 	 * change its status.  As such we can read the status here without
887 	 * fearing it will change under us.
888 	 */
889 	mode = local_read(&drvdata->mode);
890 
891 	switch (mode) {
892 	case CS_MODE_DISABLED:
893 		break;
894 	case CS_MODE_SYSFS:
895 		etm4_disable_sysfs(csdev);
896 		break;
897 	case CS_MODE_PERF:
898 		etm4_disable_perf(csdev, event);
899 		break;
900 	}
901 
902 	if (mode)
903 		local_set(&drvdata->mode, CS_MODE_DISABLED);
904 }
905 
906 static const struct coresight_ops_source etm4_source_ops = {
907 	.cpu_id		= etm4_cpu_id,
908 	.trace_id	= etm4_trace_id,
909 	.enable		= etm4_enable,
910 	.disable	= etm4_disable,
911 };
912 
913 static const struct coresight_ops etm4_cs_ops = {
914 	.source_ops	= &etm4_source_ops,
915 };
916 
cpu_supports_sysreg_trace(void)917 static inline bool cpu_supports_sysreg_trace(void)
918 {
919 	u64 dfr0 = read_sysreg_s(SYS_ID_AA64DFR0_EL1);
920 
921 	return ((dfr0 >> ID_AA64DFR0_TRACEVER_SHIFT) & 0xfUL) > 0;
922 }
923 
etm4_init_sysreg_access(struct etmv4_drvdata * drvdata,struct csdev_access * csa)924 static bool etm4_init_sysreg_access(struct etmv4_drvdata *drvdata,
925 				    struct csdev_access *csa)
926 {
927 	u32 devarch;
928 
929 	if (!cpu_supports_sysreg_trace())
930 		return false;
931 
932 	/*
933 	 * ETMs implementing sysreg access must implement TRCDEVARCH.
934 	 */
935 	devarch = read_etm4x_sysreg_const_offset(TRCDEVARCH);
936 	switch (devarch & ETM_DEVARCH_ID_MASK) {
937 	case ETM_DEVARCH_ETMv4x_ARCH:
938 		*csa = (struct csdev_access) {
939 			.io_mem	= false,
940 			.read	= etm4x_sysreg_read,
941 			.write	= etm4x_sysreg_write,
942 		};
943 		break;
944 	case ETM_DEVARCH_ETE_ARCH:
945 		*csa = (struct csdev_access) {
946 			.io_mem	= false,
947 			.read	= ete_sysreg_read,
948 			.write	= ete_sysreg_write,
949 		};
950 		break;
951 	default:
952 		return false;
953 	}
954 
955 	drvdata->arch = etm_devarch_to_arch(devarch);
956 	return true;
957 }
958 
etm4_init_iomem_access(struct etmv4_drvdata * drvdata,struct csdev_access * csa)959 static bool etm4_init_iomem_access(struct etmv4_drvdata *drvdata,
960 				   struct csdev_access *csa)
961 {
962 	u32 devarch = readl_relaxed(drvdata->base + TRCDEVARCH);
963 	u32 idr1 = readl_relaxed(drvdata->base + TRCIDR1);
964 
965 	/*
966 	 * All ETMs must implement TRCDEVARCH to indicate that
967 	 * the component is an ETMv4. To support any broken
968 	 * implementations we fall back to TRCIDR1 check, which
969 	 * is not really reliable.
970 	 */
971 	if ((devarch & ETM_DEVARCH_ID_MASK) == ETM_DEVARCH_ETMv4x_ARCH) {
972 		drvdata->arch = etm_devarch_to_arch(devarch);
973 	} else {
974 		pr_warn("CPU%d: ETM4x incompatible TRCDEVARCH: %x, falling back to TRCIDR1\n",
975 			smp_processor_id(), devarch);
976 
977 		if (ETM_TRCIDR1_ARCH_MAJOR(idr1) != ETM_TRCIDR1_ARCH_ETMv4)
978 			return false;
979 		drvdata->arch = etm_trcidr_to_arch(idr1);
980 	}
981 
982 	*csa = CSDEV_ACCESS_IOMEM(drvdata->base);
983 	return true;
984 }
985 
etm4_init_csdev_access(struct etmv4_drvdata * drvdata,struct csdev_access * csa)986 static bool etm4_init_csdev_access(struct etmv4_drvdata *drvdata,
987 				   struct csdev_access *csa)
988 {
989 	/*
990 	 * Always choose the memory mapped io, if there is
991 	 * a memory map to prevent sysreg access on broken
992 	 * systems.
993 	 */
994 	if (drvdata->base)
995 		return etm4_init_iomem_access(drvdata, csa);
996 
997 	if (etm4_init_sysreg_access(drvdata, csa))
998 		return true;
999 
1000 	return false;
1001 }
1002 
cpu_detect_trace_filtering(struct etmv4_drvdata * drvdata)1003 static void cpu_detect_trace_filtering(struct etmv4_drvdata *drvdata)
1004 {
1005 	u64 dfr0 = read_sysreg(id_aa64dfr0_el1);
1006 	u64 trfcr;
1007 
1008 	drvdata->trfcr = 0;
1009 	if (!cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_TRACE_FILT_SHIFT))
1010 		return;
1011 
1012 	/*
1013 	 * If the CPU supports v8.4 SelfHosted Tracing, enable
1014 	 * tracing at the kernel EL and EL0, forcing to use the
1015 	 * virtual time as the timestamp.
1016 	 */
1017 	trfcr = (TRFCR_ELx_TS_VIRTUAL |
1018 		 TRFCR_ELx_ExTRE |
1019 		 TRFCR_ELx_E0TRE);
1020 
1021 	/* If we are running at EL2, allow tracing the CONTEXTIDR_EL2. */
1022 	if (is_kernel_in_hyp_mode())
1023 		trfcr |= TRFCR_EL2_CX;
1024 
1025 	drvdata->trfcr = trfcr;
1026 }
1027 
etm4_init_arch_data(void * info)1028 static void etm4_init_arch_data(void *info)
1029 {
1030 	u32 etmidr0;
1031 	u32 etmidr2;
1032 	u32 etmidr3;
1033 	u32 etmidr4;
1034 	u32 etmidr5;
1035 	struct etm4_init_arg *init_arg = info;
1036 	struct etmv4_drvdata *drvdata;
1037 	struct csdev_access *csa;
1038 	int i;
1039 
1040 	drvdata = init_arg->drvdata;
1041 	csa = init_arg->csa;
1042 
1043 	/*
1044 	 * If we are unable to detect the access mechanism,
1045 	 * or unable to detect the trace unit type, fail
1046 	 * early.
1047 	 */
1048 	if (!etm4_init_csdev_access(drvdata, csa))
1049 		return;
1050 
1051 	/* Detect the support for OS Lock before we actually use it */
1052 	etm_detect_os_lock(drvdata, csa);
1053 
1054 	/* Make sure all registers are accessible */
1055 	etm4_os_unlock_csa(drvdata, csa);
1056 	etm4_cs_unlock(drvdata, csa);
1057 
1058 	etm4_check_arch_features(drvdata, init_arg->pid);
1059 
1060 	/* find all capabilities of the tracing unit */
1061 	etmidr0 = etm4x_relaxed_read32(csa, TRCIDR0);
1062 
1063 	/* INSTP0, bits[2:1] P0 tracing support field */
1064 	if (BMVAL(etmidr0, 1, 1) && BMVAL(etmidr0, 2, 2))
1065 		drvdata->instrp0 = true;
1066 	else
1067 		drvdata->instrp0 = false;
1068 
1069 	/* TRCBB, bit[5] Branch broadcast tracing support bit */
1070 	if (BMVAL(etmidr0, 5, 5))
1071 		drvdata->trcbb = true;
1072 	else
1073 		drvdata->trcbb = false;
1074 
1075 	/* TRCCOND, bit[6] Conditional instruction tracing support bit */
1076 	if (BMVAL(etmidr0, 6, 6))
1077 		drvdata->trccond = true;
1078 	else
1079 		drvdata->trccond = false;
1080 
1081 	/* TRCCCI, bit[7] Cycle counting instruction bit */
1082 	if (BMVAL(etmidr0, 7, 7))
1083 		drvdata->trccci = true;
1084 	else
1085 		drvdata->trccci = false;
1086 
1087 	/* RETSTACK, bit[9] Return stack bit */
1088 	if (BMVAL(etmidr0, 9, 9))
1089 		drvdata->retstack = true;
1090 	else
1091 		drvdata->retstack = false;
1092 
1093 	/* NUMEVENT, bits[11:10] Number of events field */
1094 	drvdata->nr_event = BMVAL(etmidr0, 10, 11);
1095 	/* QSUPP, bits[16:15] Q element support field */
1096 	drvdata->q_support = BMVAL(etmidr0, 15, 16);
1097 	/* TSSIZE, bits[28:24] Global timestamp size field */
1098 	drvdata->ts_size = BMVAL(etmidr0, 24, 28);
1099 
1100 	/* maximum size of resources */
1101 	etmidr2 = etm4x_relaxed_read32(csa, TRCIDR2);
1102 	/* CIDSIZE, bits[9:5] Indicates the Context ID size */
1103 	drvdata->ctxid_size = BMVAL(etmidr2, 5, 9);
1104 	/* VMIDSIZE, bits[14:10] Indicates the VMID size */
1105 	drvdata->vmid_size = BMVAL(etmidr2, 10, 14);
1106 	/* CCSIZE, bits[28:25] size of the cycle counter in bits minus 12 */
1107 	drvdata->ccsize = BMVAL(etmidr2, 25, 28);
1108 
1109 	etmidr3 = etm4x_relaxed_read32(csa, TRCIDR3);
1110 	/* CCITMIN, bits[11:0] minimum threshold value that can be programmed */
1111 	drvdata->ccitmin = BMVAL(etmidr3, 0, 11);
1112 	/* EXLEVEL_S, bits[19:16] Secure state instruction tracing */
1113 	drvdata->s_ex_level = BMVAL(etmidr3, 16, 19);
1114 	drvdata->config.s_ex_level = drvdata->s_ex_level;
1115 	/* EXLEVEL_NS, bits[23:20] Non-secure state instruction tracing */
1116 	drvdata->ns_ex_level = BMVAL(etmidr3, 20, 23);
1117 
1118 	/*
1119 	 * TRCERR, bit[24] whether a trace unit can trace a
1120 	 * system error exception.
1121 	 */
1122 	if (BMVAL(etmidr3, 24, 24))
1123 		drvdata->trc_error = true;
1124 	else
1125 		drvdata->trc_error = false;
1126 
1127 	/* SYNCPR, bit[25] implementation has a fixed synchronization period? */
1128 	if (BMVAL(etmidr3, 25, 25))
1129 		drvdata->syncpr = true;
1130 	else
1131 		drvdata->syncpr = false;
1132 
1133 	/* STALLCTL, bit[26] is stall control implemented? */
1134 	if (BMVAL(etmidr3, 26, 26))
1135 		drvdata->stallctl = true;
1136 	else
1137 		drvdata->stallctl = false;
1138 
1139 	/* SYSSTALL, bit[27] implementation can support stall control? */
1140 	if (BMVAL(etmidr3, 27, 27))
1141 		drvdata->sysstall = true;
1142 	else
1143 		drvdata->sysstall = false;
1144 
1145 	/* NUMPROC, bits[30:28] the number of PEs available for tracing */
1146 	drvdata->nr_pe = BMVAL(etmidr3, 28, 30);
1147 
1148 	/* NOOVERFLOW, bit[31] is trace overflow prevention supported */
1149 	if (BMVAL(etmidr3, 31, 31))
1150 		drvdata->nooverflow = true;
1151 	else
1152 		drvdata->nooverflow = false;
1153 
1154 	/* number of resources trace unit supports */
1155 	etmidr4 = etm4x_relaxed_read32(csa, TRCIDR4);
1156 	/* NUMACPAIRS, bits[0:3] number of addr comparator pairs for tracing */
1157 	drvdata->nr_addr_cmp = BMVAL(etmidr4, 0, 3);
1158 	/* NUMPC, bits[15:12] number of PE comparator inputs for tracing */
1159 	drvdata->nr_pe_cmp = BMVAL(etmidr4, 12, 15);
1160 	/*
1161 	 * NUMRSPAIR, bits[19:16]
1162 	 * The number of resource pairs conveyed by the HW starts at 0, i.e a
1163 	 * value of 0x0 indicate 1 resource pair, 0x1 indicate two and so on.
1164 	 * As such add 1 to the value of NUMRSPAIR for a better representation.
1165 	 *
1166 	 * For ETM v4.3 and later, 0x0 means 0, and no pairs are available -
1167 	 * the default TRUE and FALSE resource selectors are omitted.
1168 	 * Otherwise for values 0x1 and above the number is N + 1 as per v4.2.
1169 	 */
1170 	drvdata->nr_resource = BMVAL(etmidr4, 16, 19);
1171 	if ((drvdata->arch < ETM_ARCH_V4_3) || (drvdata->nr_resource > 0))
1172 		drvdata->nr_resource += 1;
1173 	/*
1174 	 * NUMSSCC, bits[23:20] the number of single-shot
1175 	 * comparator control for tracing. Read any status regs as these
1176 	 * also contain RO capability data.
1177 	 */
1178 	drvdata->nr_ss_cmp = BMVAL(etmidr4, 20, 23);
1179 	for (i = 0; i < drvdata->nr_ss_cmp; i++) {
1180 		drvdata->config.ss_status[i] =
1181 			etm4x_relaxed_read32(csa, TRCSSCSRn(i));
1182 	}
1183 	/* NUMCIDC, bits[27:24] number of Context ID comparators for tracing */
1184 	drvdata->numcidc = BMVAL(etmidr4, 24, 27);
1185 	/* NUMVMIDC, bits[31:28] number of VMID comparators for tracing */
1186 	drvdata->numvmidc = BMVAL(etmidr4, 28, 31);
1187 
1188 	etmidr5 = etm4x_relaxed_read32(csa, TRCIDR5);
1189 	/* NUMEXTIN, bits[8:0] number of external inputs implemented */
1190 	drvdata->nr_ext_inp = BMVAL(etmidr5, 0, 8);
1191 	/* TRACEIDSIZE, bits[21:16] indicates the trace ID width */
1192 	drvdata->trcid_size = BMVAL(etmidr5, 16, 21);
1193 	/* ATBTRIG, bit[22] implementation can support ATB triggers? */
1194 	if (BMVAL(etmidr5, 22, 22))
1195 		drvdata->atbtrig = true;
1196 	else
1197 		drvdata->atbtrig = false;
1198 	/*
1199 	 * LPOVERRIDE, bit[23] implementation supports
1200 	 * low-power state override
1201 	 */
1202 	if (BMVAL(etmidr5, 23, 23) && (!drvdata->skip_power_up))
1203 		drvdata->lpoverride = true;
1204 	else
1205 		drvdata->lpoverride = false;
1206 	/* NUMSEQSTATE, bits[27:25] number of sequencer states implemented */
1207 	drvdata->nrseqstate = BMVAL(etmidr5, 25, 27);
1208 	/* NUMCNTR, bits[30:28] number of counters available for tracing */
1209 	drvdata->nr_cntr = BMVAL(etmidr5, 28, 30);
1210 	etm4_cs_lock(drvdata, csa);
1211 	cpu_detect_trace_filtering(drvdata);
1212 }
1213 
etm4_get_victlr_access_type(struct etmv4_config * config)1214 static inline u32 etm4_get_victlr_access_type(struct etmv4_config *config)
1215 {
1216 	return etm4_get_access_type(config) << TRCVICTLR_EXLEVEL_SHIFT;
1217 }
1218 
1219 /* Set ELx trace filter access in the TRCVICTLR register */
etm4_set_victlr_access(struct etmv4_config * config)1220 static void etm4_set_victlr_access(struct etmv4_config *config)
1221 {
1222 	config->vinst_ctrl &= ~TRCVICTLR_EXLEVEL_MASK;
1223 	config->vinst_ctrl |= etm4_get_victlr_access_type(config);
1224 }
1225 
etm4_set_default_config(struct etmv4_config * config)1226 static void etm4_set_default_config(struct etmv4_config *config)
1227 {
1228 	/* disable all events tracing */
1229 	config->eventctrl0 = 0x0;
1230 	config->eventctrl1 = 0x0;
1231 
1232 	/* disable stalling */
1233 	config->stall_ctrl = 0x0;
1234 
1235 	/* enable trace synchronization every 4096 bytes, if available */
1236 	config->syncfreq = 0xC;
1237 
1238 	/* disable timestamp event */
1239 	config->ts_ctrl = 0x0;
1240 
1241 	/* TRCVICTLR::EVENT = 0x01, select the always on logic */
1242 	config->vinst_ctrl = BIT(0);
1243 
1244 	/* TRCVICTLR::EXLEVEL_NS:EXLEVELS: Set kernel / user filtering */
1245 	etm4_set_victlr_access(config);
1246 }
1247 
etm4_get_ns_access_type(struct etmv4_config * config)1248 static u64 etm4_get_ns_access_type(struct etmv4_config *config)
1249 {
1250 	u64 access_type = 0;
1251 
1252 	/*
1253 	 * EXLEVEL_NS, for NonSecure Exception levels.
1254 	 * The mask here is a generic value and must be
1255 	 * shifted to the corresponding field for the registers
1256 	 */
1257 	if (!is_kernel_in_hyp_mode()) {
1258 		/* Stay away from hypervisor mode for non-VHE */
1259 		access_type =  ETM_EXLEVEL_NS_HYP;
1260 		if (config->mode & ETM_MODE_EXCL_KERN)
1261 			access_type |= ETM_EXLEVEL_NS_OS;
1262 	} else if (config->mode & ETM_MODE_EXCL_KERN) {
1263 		access_type = ETM_EXLEVEL_NS_HYP;
1264 	}
1265 
1266 	if (config->mode & ETM_MODE_EXCL_USER)
1267 		access_type |= ETM_EXLEVEL_NS_APP;
1268 
1269 	return access_type;
1270 }
1271 
1272 /*
1273  * Construct the exception level masks for a given config.
1274  * This must be shifted to the corresponding register field
1275  * for usage.
1276  */
etm4_get_access_type(struct etmv4_config * config)1277 static u64 etm4_get_access_type(struct etmv4_config *config)
1278 {
1279 	/* All Secure exception levels are excluded from the trace */
1280 	return etm4_get_ns_access_type(config) | (u64)config->s_ex_level;
1281 }
1282 
etm4_get_comparator_access_type(struct etmv4_config * config)1283 static u64 etm4_get_comparator_access_type(struct etmv4_config *config)
1284 {
1285 	return etm4_get_access_type(config) << TRCACATR_EXLEVEL_SHIFT;
1286 }
1287 
etm4_set_comparator_filter(struct etmv4_config * config,u64 start,u64 stop,int comparator)1288 static void etm4_set_comparator_filter(struct etmv4_config *config,
1289 				       u64 start, u64 stop, int comparator)
1290 {
1291 	u64 access_type = etm4_get_comparator_access_type(config);
1292 
1293 	/* First half of default address comparator */
1294 	config->addr_val[comparator] = start;
1295 	config->addr_acc[comparator] = access_type;
1296 	config->addr_type[comparator] = ETM_ADDR_TYPE_RANGE;
1297 
1298 	/* Second half of default address comparator */
1299 	config->addr_val[comparator + 1] = stop;
1300 	config->addr_acc[comparator + 1] = access_type;
1301 	config->addr_type[comparator + 1] = ETM_ADDR_TYPE_RANGE;
1302 
1303 	/*
1304 	 * Configure the ViewInst function to include this address range
1305 	 * comparator.
1306 	 *
1307 	 * @comparator is divided by two since it is the index in the
1308 	 * etmv4_config::addr_val array but register TRCVIIECTLR deals with
1309 	 * address range comparator _pairs_.
1310 	 *
1311 	 * Therefore:
1312 	 *	index 0 -> compatator pair 0
1313 	 *	index 2 -> comparator pair 1
1314 	 *	index 4 -> comparator pair 2
1315 	 *	...
1316 	 *	index 14 -> comparator pair 7
1317 	 */
1318 	config->viiectlr |= BIT(comparator / 2);
1319 }
1320 
etm4_set_start_stop_filter(struct etmv4_config * config,u64 address,int comparator,enum etm_addr_type type)1321 static void etm4_set_start_stop_filter(struct etmv4_config *config,
1322 				       u64 address, int comparator,
1323 				       enum etm_addr_type type)
1324 {
1325 	int shift;
1326 	u64 access_type = etm4_get_comparator_access_type(config);
1327 
1328 	/* Configure the comparator */
1329 	config->addr_val[comparator] = address;
1330 	config->addr_acc[comparator] = access_type;
1331 	config->addr_type[comparator] = type;
1332 
1333 	/*
1334 	 * Configure ViewInst Start-Stop control register.
1335 	 * Addresses configured to start tracing go from bit 0 to n-1,
1336 	 * while those configured to stop tracing from 16 to 16 + n-1.
1337 	 */
1338 	shift = (type == ETM_ADDR_TYPE_START ? 0 : 16);
1339 	config->vissctlr |= BIT(shift + comparator);
1340 }
1341 
etm4_set_default_filter(struct etmv4_config * config)1342 static void etm4_set_default_filter(struct etmv4_config *config)
1343 {
1344 	/* Trace everything 'default' filter achieved by no filtering */
1345 	config->viiectlr = 0x0;
1346 
1347 	/*
1348 	 * TRCVICTLR::SSSTATUS == 1, the start-stop logic is
1349 	 * in the started state
1350 	 */
1351 	config->vinst_ctrl |= BIT(9);
1352 	config->mode |= ETM_MODE_VIEWINST_STARTSTOP;
1353 
1354 	/* No start-stop filtering for ViewInst */
1355 	config->vissctlr = 0x0;
1356 }
1357 
etm4_set_default(struct etmv4_config * config)1358 static void etm4_set_default(struct etmv4_config *config)
1359 {
1360 	if (WARN_ON_ONCE(!config))
1361 		return;
1362 
1363 	/*
1364 	 * Make default initialisation trace everything
1365 	 *
1366 	 * This is done by a minimum default config sufficient to enable
1367 	 * full instruction trace - with a default filter for trace all
1368 	 * achieved by having no filtering.
1369 	 */
1370 	etm4_set_default_config(config);
1371 	etm4_set_default_filter(config);
1372 }
1373 
etm4_get_next_comparator(struct etmv4_drvdata * drvdata,u32 type)1374 static int etm4_get_next_comparator(struct etmv4_drvdata *drvdata, u32 type)
1375 {
1376 	int nr_comparator, index = 0;
1377 	struct etmv4_config *config = &drvdata->config;
1378 
1379 	/*
1380 	 * nr_addr_cmp holds the number of comparator _pair_, so time 2
1381 	 * for the total number of comparators.
1382 	 */
1383 	nr_comparator = drvdata->nr_addr_cmp * 2;
1384 
1385 	/* Go through the tally of comparators looking for a free one. */
1386 	while (index < nr_comparator) {
1387 		switch (type) {
1388 		case ETM_ADDR_TYPE_RANGE:
1389 			if (config->addr_type[index] == ETM_ADDR_TYPE_NONE &&
1390 			    config->addr_type[index + 1] == ETM_ADDR_TYPE_NONE)
1391 				return index;
1392 
1393 			/* Address range comparators go in pairs */
1394 			index += 2;
1395 			break;
1396 		case ETM_ADDR_TYPE_START:
1397 		case ETM_ADDR_TYPE_STOP:
1398 			if (config->addr_type[index] == ETM_ADDR_TYPE_NONE)
1399 				return index;
1400 
1401 			/* Start/stop address can have odd indexes */
1402 			index += 1;
1403 			break;
1404 		default:
1405 			return -EINVAL;
1406 		}
1407 	}
1408 
1409 	/* If we are here all the comparators have been used. */
1410 	return -ENOSPC;
1411 }
1412 
etm4_set_event_filters(struct etmv4_drvdata * drvdata,struct perf_event * event)1413 static int etm4_set_event_filters(struct etmv4_drvdata *drvdata,
1414 				  struct perf_event *event)
1415 {
1416 	int i, comparator, ret = 0;
1417 	u64 address;
1418 	struct etmv4_config *config = &drvdata->config;
1419 	struct etm_filters *filters = event->hw.addr_filters;
1420 
1421 	if (!filters)
1422 		goto default_filter;
1423 
1424 	/* Sync events with what Perf got */
1425 	perf_event_addr_filters_sync(event);
1426 
1427 	/*
1428 	 * If there are no filters to deal with simply go ahead with
1429 	 * the default filter, i.e the entire address range.
1430 	 */
1431 	if (!filters->nr_filters)
1432 		goto default_filter;
1433 
1434 	for (i = 0; i < filters->nr_filters; i++) {
1435 		struct etm_filter *filter = &filters->etm_filter[i];
1436 		enum etm_addr_type type = filter->type;
1437 
1438 		/* See if a comparator is free. */
1439 		comparator = etm4_get_next_comparator(drvdata, type);
1440 		if (comparator < 0) {
1441 			ret = comparator;
1442 			goto out;
1443 		}
1444 
1445 		switch (type) {
1446 		case ETM_ADDR_TYPE_RANGE:
1447 			etm4_set_comparator_filter(config,
1448 						   filter->start_addr,
1449 						   filter->stop_addr,
1450 						   comparator);
1451 			/*
1452 			 * TRCVICTLR::SSSTATUS == 1, the start-stop logic is
1453 			 * in the started state
1454 			 */
1455 			config->vinst_ctrl |= BIT(9);
1456 
1457 			/* No start-stop filtering for ViewInst */
1458 			config->vissctlr = 0x0;
1459 			break;
1460 		case ETM_ADDR_TYPE_START:
1461 		case ETM_ADDR_TYPE_STOP:
1462 			/* Get the right start or stop address */
1463 			address = (type == ETM_ADDR_TYPE_START ?
1464 				   filter->start_addr :
1465 				   filter->stop_addr);
1466 
1467 			/* Configure comparator */
1468 			etm4_set_start_stop_filter(config, address,
1469 						   comparator, type);
1470 
1471 			/*
1472 			 * If filters::ssstatus == 1, trace acquisition was
1473 			 * started but the process was yanked away before the
1474 			 * the stop address was hit.  As such the start/stop
1475 			 * logic needs to be re-started so that tracing can
1476 			 * resume where it left.
1477 			 *
1478 			 * The start/stop logic status when a process is
1479 			 * scheduled out is checked in function
1480 			 * etm4_disable_perf().
1481 			 */
1482 			if (filters->ssstatus)
1483 				config->vinst_ctrl |= BIT(9);
1484 
1485 			/* No include/exclude filtering for ViewInst */
1486 			config->viiectlr = 0x0;
1487 			break;
1488 		default:
1489 			ret = -EINVAL;
1490 			goto out;
1491 		}
1492 	}
1493 
1494 	goto out;
1495 
1496 
1497 default_filter:
1498 	etm4_set_default_filter(config);
1499 
1500 out:
1501 	return ret;
1502 }
1503 
etm4_config_trace_mode(struct etmv4_config * config)1504 void etm4_config_trace_mode(struct etmv4_config *config)
1505 {
1506 	u32 mode;
1507 
1508 	mode = config->mode;
1509 	mode &= (ETM_MODE_EXCL_KERN | ETM_MODE_EXCL_USER);
1510 
1511 	/* excluding kernel AND user space doesn't make sense */
1512 	WARN_ON_ONCE(mode == (ETM_MODE_EXCL_KERN | ETM_MODE_EXCL_USER));
1513 
1514 	/* nothing to do if neither flags are set */
1515 	if (!(mode & ETM_MODE_EXCL_KERN) && !(mode & ETM_MODE_EXCL_USER))
1516 		return;
1517 
1518 	etm4_set_victlr_access(config);
1519 }
1520 
etm4_online_cpu(unsigned int cpu)1521 static int etm4_online_cpu(unsigned int cpu)
1522 {
1523 	if (!etmdrvdata[cpu])
1524 		return 0;
1525 
1526 	if (etmdrvdata[cpu]->boot_enable && !etmdrvdata[cpu]->sticky_enable)
1527 		coresight_enable(etmdrvdata[cpu]->csdev);
1528 	return 0;
1529 }
1530 
etm4_starting_cpu(unsigned int cpu)1531 static int etm4_starting_cpu(unsigned int cpu)
1532 {
1533 	if (!etmdrvdata[cpu])
1534 		return 0;
1535 
1536 	spin_lock(&etmdrvdata[cpu]->spinlock);
1537 	if (!etmdrvdata[cpu]->os_unlock)
1538 		etm4_os_unlock(etmdrvdata[cpu]);
1539 
1540 	if (local_read(&etmdrvdata[cpu]->mode))
1541 		etm4_enable_hw(etmdrvdata[cpu]);
1542 	spin_unlock(&etmdrvdata[cpu]->spinlock);
1543 	return 0;
1544 }
1545 
etm4_dying_cpu(unsigned int cpu)1546 static int etm4_dying_cpu(unsigned int cpu)
1547 {
1548 	if (!etmdrvdata[cpu])
1549 		return 0;
1550 
1551 	spin_lock(&etmdrvdata[cpu]->spinlock);
1552 	if (local_read(&etmdrvdata[cpu]->mode))
1553 		etm4_disable_hw(etmdrvdata[cpu]);
1554 	spin_unlock(&etmdrvdata[cpu]->spinlock);
1555 	return 0;
1556 }
1557 
etm4_init_trace_id(struct etmv4_drvdata * drvdata)1558 static void etm4_init_trace_id(struct etmv4_drvdata *drvdata)
1559 {
1560 	drvdata->trcid = coresight_get_trace_id(drvdata->cpu);
1561 }
1562 
__etm4_cpu_save(struct etmv4_drvdata * drvdata)1563 static int __etm4_cpu_save(struct etmv4_drvdata *drvdata)
1564 {
1565 	int i, ret = 0;
1566 	struct etmv4_save_state *state;
1567 	struct coresight_device *csdev = drvdata->csdev;
1568 	struct csdev_access *csa;
1569 	struct device *etm_dev;
1570 
1571 	if (WARN_ON(!csdev))
1572 		return -ENODEV;
1573 
1574 	etm_dev = &csdev->dev;
1575 	csa = &csdev->access;
1576 
1577 	/*
1578 	 * As recommended by 3.4.1 ("The procedure when powering down the PE")
1579 	 * of ARM IHI 0064D
1580 	 */
1581 	dsb(sy);
1582 	isb();
1583 
1584 	etm4_cs_unlock(drvdata, csa);
1585 	/* Lock the OS lock to disable trace and external debugger access */
1586 	etm4_os_lock(drvdata);
1587 
1588 	/* wait for TRCSTATR.PMSTABLE to go up */
1589 	if (coresight_timeout(csa, TRCSTATR, TRCSTATR_PMSTABLE_BIT, 1)) {
1590 		dev_err(etm_dev,
1591 			"timeout while waiting for PM Stable Status\n");
1592 		etm4_os_unlock(drvdata);
1593 		ret = -EBUSY;
1594 		goto out;
1595 	}
1596 
1597 	state = drvdata->save_state;
1598 
1599 	state->trcprgctlr = etm4x_read32(csa, TRCPRGCTLR);
1600 	if (drvdata->nr_pe)
1601 		state->trcprocselr = etm4x_read32(csa, TRCPROCSELR);
1602 	state->trcconfigr = etm4x_read32(csa, TRCCONFIGR);
1603 	state->trcauxctlr = etm4x_read32(csa, TRCAUXCTLR);
1604 	state->trceventctl0r = etm4x_read32(csa, TRCEVENTCTL0R);
1605 	state->trceventctl1r = etm4x_read32(csa, TRCEVENTCTL1R);
1606 	if (drvdata->stallctl)
1607 		state->trcstallctlr = etm4x_read32(csa, TRCSTALLCTLR);
1608 	state->trctsctlr = etm4x_read32(csa, TRCTSCTLR);
1609 	state->trcsyncpr = etm4x_read32(csa, TRCSYNCPR);
1610 	state->trcccctlr = etm4x_read32(csa, TRCCCCTLR);
1611 	state->trcbbctlr = etm4x_read32(csa, TRCBBCTLR);
1612 	state->trctraceidr = etm4x_read32(csa, TRCTRACEIDR);
1613 	state->trcqctlr = etm4x_read32(csa, TRCQCTLR);
1614 
1615 	state->trcvictlr = etm4x_read32(csa, TRCVICTLR);
1616 	state->trcviiectlr = etm4x_read32(csa, TRCVIIECTLR);
1617 	state->trcvissctlr = etm4x_read32(csa, TRCVISSCTLR);
1618 	if (drvdata->nr_pe_cmp)
1619 		state->trcvipcssctlr = etm4x_read32(csa, TRCVIPCSSCTLR);
1620 	state->trcvdctlr = etm4x_read32(csa, TRCVDCTLR);
1621 	state->trcvdsacctlr = etm4x_read32(csa, TRCVDSACCTLR);
1622 	state->trcvdarcctlr = etm4x_read32(csa, TRCVDARCCTLR);
1623 
1624 	for (i = 0; i < drvdata->nrseqstate - 1; i++)
1625 		state->trcseqevr[i] = etm4x_read32(csa, TRCSEQEVRn(i));
1626 
1627 	state->trcseqrstevr = etm4x_read32(csa, TRCSEQRSTEVR);
1628 	state->trcseqstr = etm4x_read32(csa, TRCSEQSTR);
1629 	state->trcextinselr = etm4x_read32(csa, TRCEXTINSELR);
1630 
1631 	for (i = 0; i < drvdata->nr_cntr; i++) {
1632 		state->trccntrldvr[i] = etm4x_read32(csa, TRCCNTRLDVRn(i));
1633 		state->trccntctlr[i] = etm4x_read32(csa, TRCCNTCTLRn(i));
1634 		state->trccntvr[i] = etm4x_read32(csa, TRCCNTVRn(i));
1635 	}
1636 
1637 	for (i = 0; i < drvdata->nr_resource * 2; i++)
1638 		state->trcrsctlr[i] = etm4x_read32(csa, TRCRSCTLRn(i));
1639 
1640 	for (i = 0; i < drvdata->nr_ss_cmp; i++) {
1641 		state->trcssccr[i] = etm4x_read32(csa, TRCSSCCRn(i));
1642 		state->trcsscsr[i] = etm4x_read32(csa, TRCSSCSRn(i));
1643 		if (etm4x_sspcicrn_present(drvdata, i))
1644 			state->trcsspcicr[i] = etm4x_read32(csa, TRCSSPCICRn(i));
1645 	}
1646 
1647 	for (i = 0; i < drvdata->nr_addr_cmp * 2; i++) {
1648 		state->trcacvr[i] = etm4x_read64(csa, TRCACVRn(i));
1649 		state->trcacatr[i] = etm4x_read64(csa, TRCACATRn(i));
1650 	}
1651 
1652 	/*
1653 	 * Data trace stream is architecturally prohibited for A profile cores
1654 	 * so we don't save (or later restore) trcdvcvr and trcdvcmr - As per
1655 	 * section 1.3.4 ("Possible functional configurations of an ETMv4 trace
1656 	 * unit") of ARM IHI 0064D.
1657 	 */
1658 
1659 	for (i = 0; i < drvdata->numcidc; i++)
1660 		state->trccidcvr[i] = etm4x_read64(csa, TRCCIDCVRn(i));
1661 
1662 	for (i = 0; i < drvdata->numvmidc; i++)
1663 		state->trcvmidcvr[i] = etm4x_read64(csa, TRCVMIDCVRn(i));
1664 
1665 	state->trccidcctlr0 = etm4x_read32(csa, TRCCIDCCTLR0);
1666 	if (drvdata->numcidc > 4)
1667 		state->trccidcctlr1 = etm4x_read32(csa, TRCCIDCCTLR1);
1668 
1669 	state->trcvmidcctlr0 = etm4x_read32(csa, TRCVMIDCCTLR0);
1670 	if (drvdata->numvmidc > 4)
1671 		state->trcvmidcctlr0 = etm4x_read32(csa, TRCVMIDCCTLR1);
1672 
1673 	state->trcclaimset = etm4x_read32(csa, TRCCLAIMCLR);
1674 
1675 	if (!drvdata->skip_power_up)
1676 		state->trcpdcr = etm4x_read32(csa, TRCPDCR);
1677 
1678 	/* wait for TRCSTATR.IDLE to go up */
1679 	if (coresight_timeout(csa, TRCSTATR, TRCSTATR_IDLE_BIT, 1)) {
1680 		dev_err(etm_dev,
1681 			"timeout while waiting for Idle Trace Status\n");
1682 		etm4_os_unlock(drvdata);
1683 		ret = -EBUSY;
1684 		goto out;
1685 	}
1686 
1687 	drvdata->state_needs_restore = true;
1688 
1689 	/*
1690 	 * Power can be removed from the trace unit now. We do this to
1691 	 * potentially save power on systems that respect the TRCPDCR_PU
1692 	 * despite requesting software to save/restore state.
1693 	 */
1694 	if (!drvdata->skip_power_up)
1695 		etm4x_relaxed_write32(csa, (state->trcpdcr & ~TRCPDCR_PU),
1696 				      TRCPDCR);
1697 out:
1698 	etm4_cs_lock(drvdata, csa);
1699 	return ret;
1700 }
1701 
etm4_cpu_save(struct etmv4_drvdata * drvdata)1702 static int etm4_cpu_save(struct etmv4_drvdata *drvdata)
1703 {
1704 	int ret = 0;
1705 
1706 	/* Save the TRFCR irrespective of whether the ETM is ON */
1707 	if (drvdata->trfcr)
1708 		drvdata->save_trfcr = read_trfcr();
1709 	/*
1710 	 * Save and restore the ETM Trace registers only if
1711 	 * the ETM is active.
1712 	 */
1713 	if (local_read(&drvdata->mode) && drvdata->save_state)
1714 		ret = __etm4_cpu_save(drvdata);
1715 	return ret;
1716 }
1717 
__etm4_cpu_restore(struct etmv4_drvdata * drvdata)1718 static void __etm4_cpu_restore(struct etmv4_drvdata *drvdata)
1719 {
1720 	int i;
1721 	struct etmv4_save_state *state = drvdata->save_state;
1722 	struct csdev_access tmp_csa = CSDEV_ACCESS_IOMEM(drvdata->base);
1723 	struct csdev_access *csa = &tmp_csa;
1724 
1725 	etm4_cs_unlock(drvdata, csa);
1726 	etm4x_relaxed_write32(csa, state->trcclaimset, TRCCLAIMSET);
1727 
1728 	etm4x_relaxed_write32(csa, state->trcprgctlr, TRCPRGCTLR);
1729 	if (drvdata->nr_pe)
1730 		etm4x_relaxed_write32(csa, state->trcprocselr, TRCPROCSELR);
1731 	etm4x_relaxed_write32(csa, state->trcconfigr, TRCCONFIGR);
1732 	etm4x_relaxed_write32(csa, state->trcauxctlr, TRCAUXCTLR);
1733 	etm4x_relaxed_write32(csa, state->trceventctl0r, TRCEVENTCTL0R);
1734 	etm4x_relaxed_write32(csa, state->trceventctl1r, TRCEVENTCTL1R);
1735 	if (drvdata->stallctl)
1736 		etm4x_relaxed_write32(csa, state->trcstallctlr, TRCSTALLCTLR);
1737 	etm4x_relaxed_write32(csa, state->trctsctlr, TRCTSCTLR);
1738 	etm4x_relaxed_write32(csa, state->trcsyncpr, TRCSYNCPR);
1739 	etm4x_relaxed_write32(csa, state->trcccctlr, TRCCCCTLR);
1740 	etm4x_relaxed_write32(csa, state->trcbbctlr, TRCBBCTLR);
1741 	etm4x_relaxed_write32(csa, state->trctraceidr, TRCTRACEIDR);
1742 	etm4x_relaxed_write32(csa, state->trcqctlr, TRCQCTLR);
1743 
1744 	etm4x_relaxed_write32(csa, state->trcvictlr, TRCVICTLR);
1745 	etm4x_relaxed_write32(csa, state->trcviiectlr, TRCVIIECTLR);
1746 	etm4x_relaxed_write32(csa, state->trcvissctlr, TRCVISSCTLR);
1747 	if (drvdata->nr_pe_cmp)
1748 		etm4x_relaxed_write32(csa, state->trcvipcssctlr, TRCVIPCSSCTLR);
1749 	etm4x_relaxed_write32(csa, state->trcvdctlr, TRCVDCTLR);
1750 	etm4x_relaxed_write32(csa, state->trcvdsacctlr, TRCVDSACCTLR);
1751 	etm4x_relaxed_write32(csa, state->trcvdarcctlr, TRCVDARCCTLR);
1752 
1753 	for (i = 0; i < drvdata->nrseqstate - 1; i++)
1754 		etm4x_relaxed_write32(csa, state->trcseqevr[i], TRCSEQEVRn(i));
1755 
1756 	etm4x_relaxed_write32(csa, state->trcseqrstevr, TRCSEQRSTEVR);
1757 	etm4x_relaxed_write32(csa, state->trcseqstr, TRCSEQSTR);
1758 	etm4x_relaxed_write32(csa, state->trcextinselr, TRCEXTINSELR);
1759 
1760 	for (i = 0; i < drvdata->nr_cntr; i++) {
1761 		etm4x_relaxed_write32(csa, state->trccntrldvr[i], TRCCNTRLDVRn(i));
1762 		etm4x_relaxed_write32(csa, state->trccntctlr[i], TRCCNTCTLRn(i));
1763 		etm4x_relaxed_write32(csa, state->trccntvr[i], TRCCNTVRn(i));
1764 	}
1765 
1766 	for (i = 0; i < drvdata->nr_resource * 2; i++)
1767 		etm4x_relaxed_write32(csa, state->trcrsctlr[i], TRCRSCTLRn(i));
1768 
1769 	for (i = 0; i < drvdata->nr_ss_cmp; i++) {
1770 		etm4x_relaxed_write32(csa, state->trcssccr[i], TRCSSCCRn(i));
1771 		etm4x_relaxed_write32(csa, state->trcsscsr[i], TRCSSCSRn(i));
1772 		if (etm4x_sspcicrn_present(drvdata, i))
1773 			etm4x_relaxed_write32(csa, state->trcsspcicr[i], TRCSSPCICRn(i));
1774 	}
1775 
1776 	for (i = 0; i < drvdata->nr_addr_cmp * 2; i++) {
1777 		etm4x_relaxed_write64(csa, state->trcacvr[i], TRCACVRn(i));
1778 		etm4x_relaxed_write64(csa, state->trcacatr[i], TRCACATRn(i));
1779 	}
1780 
1781 	for (i = 0; i < drvdata->numcidc; i++)
1782 		etm4x_relaxed_write64(csa, state->trccidcvr[i], TRCCIDCVRn(i));
1783 
1784 	for (i = 0; i < drvdata->numvmidc; i++)
1785 		etm4x_relaxed_write64(csa, state->trcvmidcvr[i], TRCVMIDCVRn(i));
1786 
1787 	etm4x_relaxed_write32(csa, state->trccidcctlr0, TRCCIDCCTLR0);
1788 	if (drvdata->numcidc > 4)
1789 		etm4x_relaxed_write32(csa, state->trccidcctlr1, TRCCIDCCTLR1);
1790 
1791 	etm4x_relaxed_write32(csa, state->trcvmidcctlr0, TRCVMIDCCTLR0);
1792 	if (drvdata->numvmidc > 4)
1793 		etm4x_relaxed_write32(csa, state->trcvmidcctlr0, TRCVMIDCCTLR1);
1794 
1795 	etm4x_relaxed_write32(csa, state->trcclaimset, TRCCLAIMSET);
1796 
1797 	if (!drvdata->skip_power_up)
1798 		etm4x_relaxed_write32(csa, state->trcpdcr, TRCPDCR);
1799 
1800 	drvdata->state_needs_restore = false;
1801 
1802 	/*
1803 	 * As recommended by section 4.3.7 ("Synchronization when using the
1804 	 * memory-mapped interface") of ARM IHI 0064D
1805 	 */
1806 	dsb(sy);
1807 	isb();
1808 
1809 	/* Unlock the OS lock to re-enable trace and external debug access */
1810 	etm4_os_unlock(drvdata);
1811 	etm4_cs_lock(drvdata, csa);
1812 }
1813 
etm4_cpu_restore(struct etmv4_drvdata * drvdata)1814 static void etm4_cpu_restore(struct etmv4_drvdata *drvdata)
1815 {
1816 	if (drvdata->trfcr)
1817 		write_trfcr(drvdata->save_trfcr);
1818 	if (drvdata->state_needs_restore)
1819 		__etm4_cpu_restore(drvdata);
1820 }
1821 
etm4_cpu_pm_notify(struct notifier_block * nb,unsigned long cmd,void * v)1822 static int etm4_cpu_pm_notify(struct notifier_block *nb, unsigned long cmd,
1823 			      void *v)
1824 {
1825 	struct etmv4_drvdata *drvdata;
1826 	unsigned int cpu = smp_processor_id();
1827 
1828 	if (!etmdrvdata[cpu])
1829 		return NOTIFY_OK;
1830 
1831 	drvdata = etmdrvdata[cpu];
1832 
1833 	if (WARN_ON_ONCE(drvdata->cpu != cpu))
1834 		return NOTIFY_BAD;
1835 
1836 	switch (cmd) {
1837 	case CPU_PM_ENTER:
1838 		if (etm4_cpu_save(drvdata))
1839 			return NOTIFY_BAD;
1840 		break;
1841 	case CPU_PM_EXIT:
1842 	case CPU_PM_ENTER_FAILED:
1843 		etm4_cpu_restore(drvdata);
1844 		break;
1845 	default:
1846 		return NOTIFY_DONE;
1847 	}
1848 
1849 	return NOTIFY_OK;
1850 }
1851 
1852 static struct notifier_block etm4_cpu_pm_nb = {
1853 	.notifier_call = etm4_cpu_pm_notify,
1854 };
1855 
1856 /* Setup PM. Deals with error conditions and counts */
etm4_pm_setup(void)1857 static int __init etm4_pm_setup(void)
1858 {
1859 	int ret;
1860 
1861 	ret = cpu_pm_register_notifier(&etm4_cpu_pm_nb);
1862 	if (ret)
1863 		return ret;
1864 
1865 	ret = cpuhp_setup_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING,
1866 					"arm/coresight4:starting",
1867 					etm4_starting_cpu, etm4_dying_cpu);
1868 
1869 	if (ret)
1870 		goto unregister_notifier;
1871 
1872 	ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
1873 					"arm/coresight4:online",
1874 					etm4_online_cpu, NULL);
1875 
1876 	/* HP dyn state ID returned in ret on success */
1877 	if (ret > 0) {
1878 		hp_online = ret;
1879 		return 0;
1880 	}
1881 
1882 	/* failed dyn state - remove others */
1883 	cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING);
1884 
1885 unregister_notifier:
1886 	cpu_pm_unregister_notifier(&etm4_cpu_pm_nb);
1887 	return ret;
1888 }
1889 
etm4_pm_clear(void)1890 static void etm4_pm_clear(void)
1891 {
1892 	cpu_pm_unregister_notifier(&etm4_cpu_pm_nb);
1893 	cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING);
1894 	if (hp_online) {
1895 		cpuhp_remove_state_nocalls(hp_online);
1896 		hp_online = 0;
1897 	}
1898 }
1899 
etm4_probe(struct device * dev,void __iomem * base,u32 etm_pid)1900 static int etm4_probe(struct device *dev, void __iomem *base, u32 etm_pid)
1901 {
1902 	int ret;
1903 	struct coresight_platform_data *pdata = NULL;
1904 	struct etmv4_drvdata *drvdata;
1905 	struct coresight_desc desc = { 0 };
1906 	struct etm4_init_arg init_arg = { 0 };
1907 	u8 major, minor;
1908 	char *type_name;
1909 
1910 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
1911 	if (!drvdata)
1912 		return -ENOMEM;
1913 
1914 	dev_set_drvdata(dev, drvdata);
1915 
1916 	if (pm_save_enable == PARAM_PM_SAVE_FIRMWARE)
1917 		pm_save_enable = coresight_loses_context_with_cpu(dev) ?
1918 			       PARAM_PM_SAVE_SELF_HOSTED : PARAM_PM_SAVE_NEVER;
1919 
1920 	if (pm_save_enable != PARAM_PM_SAVE_NEVER) {
1921 		drvdata->save_state = devm_kmalloc(dev,
1922 				sizeof(struct etmv4_save_state), GFP_KERNEL);
1923 		if (!drvdata->save_state)
1924 			return -ENOMEM;
1925 	}
1926 
1927 	drvdata->base = base;
1928 
1929 	spin_lock_init(&drvdata->spinlock);
1930 
1931 	drvdata->cpu = coresight_get_cpu(dev);
1932 	if (drvdata->cpu < 0)
1933 		return drvdata->cpu;
1934 
1935 	init_arg.drvdata = drvdata;
1936 	init_arg.csa = &desc.access;
1937 	init_arg.pid = etm_pid;
1938 
1939 	if (smp_call_function_single(drvdata->cpu,
1940 				etm4_init_arch_data,  &init_arg, 1))
1941 		dev_err(dev, "ETM arch init failed\n");
1942 
1943 	if (!drvdata->arch)
1944 		return -EINVAL;
1945 
1946 	/* TRCPDCR is not accessible with system instructions. */
1947 	if (!desc.access.io_mem ||
1948 	    fwnode_property_present(dev_fwnode(dev), "qcom,skip-power-up"))
1949 		drvdata->skip_power_up = true;
1950 
1951 	major = ETM_ARCH_MAJOR_VERSION(drvdata->arch);
1952 	minor = ETM_ARCH_MINOR_VERSION(drvdata->arch);
1953 
1954 	if (etm4x_is_ete(drvdata)) {
1955 		type_name = "ete";
1956 		/* ETE v1 has major version == 0b101. Adjust this for logging.*/
1957 		major -= 4;
1958 	} else {
1959 		type_name = "etm";
1960 	}
1961 
1962 	desc.name = devm_kasprintf(dev, GFP_KERNEL,
1963 				   "%s%d", type_name, drvdata->cpu);
1964 	if (!desc.name)
1965 		return -ENOMEM;
1966 
1967 	etm4_init_trace_id(drvdata);
1968 	etm4_set_default(&drvdata->config);
1969 
1970 	pdata = coresight_get_platform_data(dev);
1971 	if (IS_ERR(pdata))
1972 		return PTR_ERR(pdata);
1973 
1974 	dev->platform_data = pdata;
1975 
1976 	desc.type = CORESIGHT_DEV_TYPE_SOURCE;
1977 	desc.subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_PROC;
1978 	desc.ops = &etm4_cs_ops;
1979 	desc.pdata = pdata;
1980 	desc.dev = dev;
1981 	desc.groups = coresight_etmv4_groups;
1982 	drvdata->csdev = coresight_register(&desc);
1983 	if (IS_ERR(drvdata->csdev))
1984 		return PTR_ERR(drvdata->csdev);
1985 
1986 	ret = etm_perf_symlink(drvdata->csdev, true);
1987 	if (ret) {
1988 		coresight_unregister(drvdata->csdev);
1989 		return ret;
1990 	}
1991 
1992 	etmdrvdata[drvdata->cpu] = drvdata;
1993 
1994 	dev_info(&drvdata->csdev->dev, "CPU%d: %s v%d.%d initialized\n",
1995 		 drvdata->cpu, type_name, major, minor);
1996 
1997 	if (boot_enable) {
1998 		coresight_enable(drvdata->csdev);
1999 		drvdata->boot_enable = true;
2000 	}
2001 
2002 	return 0;
2003 }
2004 
etm4_probe_amba(struct amba_device * adev,const struct amba_id * id)2005 static int etm4_probe_amba(struct amba_device *adev, const struct amba_id *id)
2006 {
2007 	void __iomem *base;
2008 	struct device *dev = &adev->dev;
2009 	struct resource *res = &adev->res;
2010 	int ret;
2011 
2012 	/* Validity for the resource is already checked by the AMBA core */
2013 	base = devm_ioremap_resource(dev, res);
2014 	if (IS_ERR(base))
2015 		return PTR_ERR(base);
2016 
2017 	ret = etm4_probe(dev, base, id->id);
2018 	if (!ret)
2019 		pm_runtime_put(&adev->dev);
2020 
2021 	return ret;
2022 }
2023 
etm4_probe_platform_dev(struct platform_device * pdev)2024 static int etm4_probe_platform_dev(struct platform_device *pdev)
2025 {
2026 	int ret;
2027 
2028 	pm_runtime_get_noresume(&pdev->dev);
2029 	pm_runtime_set_active(&pdev->dev);
2030 	pm_runtime_enable(&pdev->dev);
2031 
2032 	/*
2033 	 * System register based devices could match the
2034 	 * HW by reading appropriate registers on the HW
2035 	 * and thus we could skip the PID.
2036 	 */
2037 	ret = etm4_probe(&pdev->dev, NULL, 0);
2038 
2039 	pm_runtime_put(&pdev->dev);
2040 	return ret;
2041 }
2042 
2043 static struct amba_cs_uci_id uci_id_etm4[] = {
2044 	{
2045 		/*  ETMv4 UCI data */
2046 		.devarch	= ETM_DEVARCH_ETMv4x_ARCH,
2047 		.devarch_mask	= ETM_DEVARCH_ID_MASK,
2048 		.devtype	= 0x00000013,
2049 	}
2050 };
2051 
clear_etmdrvdata(void * info)2052 static void clear_etmdrvdata(void *info)
2053 {
2054 	int cpu = *(int *)info;
2055 
2056 	etmdrvdata[cpu] = NULL;
2057 }
2058 
etm4_remove_dev(struct etmv4_drvdata * drvdata)2059 static void __exit etm4_remove_dev(struct etmv4_drvdata *drvdata)
2060 {
2061 	etm_perf_symlink(drvdata->csdev, false);
2062 	/*
2063 	 * Taking hotplug lock here to avoid racing between etm4_remove_dev()
2064 	 * and CPU hotplug call backs.
2065 	 */
2066 	cpus_read_lock();
2067 	/*
2068 	 * The readers for etmdrvdata[] are CPU hotplug call backs
2069 	 * and PM notification call backs. Change etmdrvdata[i] on
2070 	 * CPU i ensures these call backs has consistent view
2071 	 * inside one call back function.
2072 	 */
2073 	if (smp_call_function_single(drvdata->cpu, clear_etmdrvdata, &drvdata->cpu, 1))
2074 		etmdrvdata[drvdata->cpu] = NULL;
2075 
2076 	cpus_read_unlock();
2077 
2078 	coresight_unregister(drvdata->csdev);
2079 }
2080 
etm4_remove_amba(struct amba_device * adev)2081 static void __exit etm4_remove_amba(struct amba_device *adev)
2082 {
2083 	struct etmv4_drvdata *drvdata = dev_get_drvdata(&adev->dev);
2084 
2085 	if (drvdata)
2086 		etm4_remove_dev(drvdata);
2087 }
2088 
etm4_remove_platform_dev(struct platform_device * pdev)2089 static int __exit etm4_remove_platform_dev(struct platform_device *pdev)
2090 {
2091 	int ret = 0;
2092 	struct etmv4_drvdata *drvdata = dev_get_drvdata(&pdev->dev);
2093 
2094 	if (drvdata)
2095 		etm4_remove_dev(drvdata);
2096 	pm_runtime_disable(&pdev->dev);
2097 	return ret;
2098 }
2099 
2100 static const struct amba_id etm4_ids[] = {
2101 	CS_AMBA_ID(0x000bb95d),			/* Cortex-A53 */
2102 	CS_AMBA_ID(0x000bb95e),			/* Cortex-A57 */
2103 	CS_AMBA_ID(0x000bb95a),			/* Cortex-A72 */
2104 	CS_AMBA_ID(0x000bb959),			/* Cortex-A73 */
2105 	CS_AMBA_UCI_ID(0x000bb9da, uci_id_etm4),/* Cortex-A35 */
2106 	CS_AMBA_UCI_ID(0x000bbd05, uci_id_etm4),/* Cortex-A55 */
2107 	CS_AMBA_UCI_ID(0x000bbd0a, uci_id_etm4),/* Cortex-A75 */
2108 	CS_AMBA_UCI_ID(0x000bbd0c, uci_id_etm4),/* Neoverse N1 */
2109 	CS_AMBA_UCI_ID(0x000f0205, uci_id_etm4),/* Qualcomm Kryo */
2110 	CS_AMBA_UCI_ID(0x000f0211, uci_id_etm4),/* Qualcomm Kryo */
2111 	CS_AMBA_UCI_ID(0x000bb802, uci_id_etm4),/* Qualcomm Kryo 385 Cortex-A55 */
2112 	CS_AMBA_UCI_ID(0x000bb803, uci_id_etm4),/* Qualcomm Kryo 385 Cortex-A75 */
2113 	CS_AMBA_UCI_ID(0x000bb805, uci_id_etm4),/* Qualcomm Kryo 4XX Cortex-A55 */
2114 	CS_AMBA_UCI_ID(0x000bb804, uci_id_etm4),/* Qualcomm Kryo 4XX Cortex-A76 */
2115 	CS_AMBA_UCI_ID(0x000cc0af, uci_id_etm4),/* Marvell ThunderX2 */
2116 	CS_AMBA_UCI_ID(0x000b6d01, uci_id_etm4),/* HiSilicon-Hip08 */
2117 	CS_AMBA_UCI_ID(0x000b6d02, uci_id_etm4),/* HiSilicon-Hip09 */
2118 	{},
2119 };
2120 
2121 MODULE_DEVICE_TABLE(amba, etm4_ids);
2122 
2123 static struct amba_driver etm4x_amba_driver = {
2124 	.drv = {
2125 		.name   = "coresight-etm4x",
2126 		.owner  = THIS_MODULE,
2127 		.suppress_bind_attrs = true,
2128 	},
2129 	.probe		= etm4_probe_amba,
2130 	.remove         = etm4_remove_amba,
2131 	.id_table	= etm4_ids,
2132 };
2133 
2134 static const struct of_device_id etm4_sysreg_match[] = {
2135 	{ .compatible	= "arm,coresight-etm4x-sysreg" },
2136 	{ .compatible	= "arm,embedded-trace-extension" },
2137 	{}
2138 };
2139 
2140 static struct platform_driver etm4_platform_driver = {
2141 	.probe		= etm4_probe_platform_dev,
2142 	.remove		= etm4_remove_platform_dev,
2143 	.driver			= {
2144 		.name			= "coresight-etm4x",
2145 		.of_match_table		= etm4_sysreg_match,
2146 		.suppress_bind_attrs	= true,
2147 	},
2148 };
2149 
etm4x_init(void)2150 static int __init etm4x_init(void)
2151 {
2152 	int ret;
2153 
2154 	ret = etm4_pm_setup();
2155 
2156 	/* etm4_pm_setup() does its own cleanup - exit on error */
2157 	if (ret)
2158 		return ret;
2159 
2160 	ret = amba_driver_register(&etm4x_amba_driver);
2161 	if (ret) {
2162 		pr_err("Error registering etm4x AMBA driver\n");
2163 		goto clear_pm;
2164 	}
2165 
2166 	ret = platform_driver_register(&etm4_platform_driver);
2167 	if (!ret)
2168 		return 0;
2169 
2170 	pr_err("Error registering etm4x platform driver\n");
2171 	amba_driver_unregister(&etm4x_amba_driver);
2172 
2173 clear_pm:
2174 	etm4_pm_clear();
2175 	return ret;
2176 }
2177 
etm4x_exit(void)2178 static void __exit etm4x_exit(void)
2179 {
2180 	amba_driver_unregister(&etm4x_amba_driver);
2181 	platform_driver_unregister(&etm4_platform_driver);
2182 	etm4_pm_clear();
2183 }
2184 
2185 module_init(etm4x_init);
2186 module_exit(etm4x_exit);
2187 
2188 MODULE_AUTHOR("Pratik Patel <pratikp@codeaurora.org>");
2189 MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@linaro.org>");
2190 MODULE_DESCRIPTION("Arm CoreSight Program Flow Trace v4.x driver");
2191 MODULE_LICENSE("GPL v2");
2192