xref: /freebsd/sys/dev/hwpmc/hwpmc_arm64.c (revision 6e563a1b608438504d963c2d7c70e50d2e75af46)
1 /*-
2  * Copyright (c) 2015 Ruslan Bukin <br@bsdpad.com>
3  * All rights reserved.
4  *
5  * This software was developed by the University of Cambridge Computer
6  * Laboratory with support from ARM Ltd.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/pmc.h>
36 #include <sys/pmckern.h>
37 
38 #include <machine/pmc_mdep.h>
39 #include <machine/cpu.h>
40 
41 static int arm64_npmcs;
42 
43 struct arm64_event_code_map {
44 	enum pmc_event	pe_ev;
45 	uint8_t		pe_code;
46 };
47 
48 /*
49  * Per-processor information.
50  */
51 struct arm64_cpu {
52 	struct pmc_hw   *pc_arm64pmcs;
53 };
54 
55 static struct arm64_cpu **arm64_pcpu;
56 
57 /*
58  * Interrupt Enable Set Register
59  */
60 static __inline void
61 arm64_interrupt_enable(uint32_t pmc)
62 {
63 	uint32_t reg;
64 
65 	reg = (1 << pmc);
66 	WRITE_SPECIALREG(pmintenset_el1, reg);
67 
68 	isb();
69 }
70 
71 /*
72  * Interrupt Clear Set Register
73  */
74 static __inline void
75 arm64_interrupt_disable(uint32_t pmc)
76 {
77 	uint32_t reg;
78 
79 	reg = (1 << pmc);
80 	WRITE_SPECIALREG(pmintenclr_el1, reg);
81 
82 	isb();
83 }
84 
85 /*
86  * Counter Set Enable Register
87  */
88 static __inline void
89 arm64_counter_enable(unsigned int pmc)
90 {
91 	uint32_t reg;
92 
93 	reg = (1 << pmc);
94 	WRITE_SPECIALREG(pmcntenset_el0, reg);
95 
96 	isb();
97 }
98 
99 /*
100  * Counter Clear Enable Register
101  */
102 static __inline void
103 arm64_counter_disable(unsigned int pmc)
104 {
105 	uint32_t reg;
106 
107 	reg = (1 << pmc);
108 	WRITE_SPECIALREG(pmcntenclr_el0, reg);
109 
110 	isb();
111 }
112 
113 /*
114  * Performance Monitors Control Register
115  */
116 static uint32_t
117 arm64_pmcr_read(void)
118 {
119 	uint32_t reg;
120 
121 	reg = READ_SPECIALREG(pmcr_el0);
122 
123 	return (reg);
124 }
125 
126 static void
127 arm64_pmcr_write(uint32_t reg)
128 {
129 
130 	WRITE_SPECIALREG(pmcr_el0, reg);
131 
132 	isb();
133 }
134 
135 /*
136  * Performance Count Register N
137  */
138 static uint32_t
139 arm64_pmcn_read(unsigned int pmc)
140 {
141 
142 	KASSERT(pmc < arm64_npmcs, ("%s: illegal PMC number %d", __func__, pmc));
143 
144 	WRITE_SPECIALREG(pmselr_el0, pmc);
145 
146 	isb();
147 
148 	return (READ_SPECIALREG(pmxevcntr_el0));
149 }
150 
151 static void
152 arm64_pmcn_write(unsigned int pmc, uint32_t reg)
153 {
154 
155 	KASSERT(pmc < arm64_npmcs, ("%s: illegal PMC number %d", __func__, pmc));
156 
157 	WRITE_SPECIALREG(pmselr_el0, pmc);
158 	WRITE_SPECIALREG(pmxevcntr_el0, reg);
159 
160 	isb();
161 }
162 
163 static int
164 arm64_allocate_pmc(int cpu, int ri, struct pmc *pm,
165   const struct pmc_op_pmcallocate *a)
166 {
167 	uint32_t config;
168 	enum pmc_event pe;
169 
170 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
171 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
172 	KASSERT(ri >= 0 && ri < arm64_npmcs,
173 	    ("[arm64,%d] illegal row index %d", __LINE__, ri));
174 
175 	if (a->pm_class != PMC_CLASS_ARMV8) {
176 		return (EINVAL);
177 	}
178 	pe = a->pm_ev;
179 
180 	/* Adjust the config value if needed. */
181 	config = a->pm_md.pm_md_config;
182 	if ((a->pm_md.pm_md_flags & PM_MD_RAW_EVENT) == 0) {
183 		config = (uint32_t)pe - PMC_EV_ARMV8_FIRST;
184 		if (config > (PMC_EV_ARMV8_LAST - PMC_EV_ARMV8_FIRST))
185 			return (EINVAL);
186 	}
187 
188 	switch (a->pm_caps & (PMC_CAP_SYSTEM | PMC_CAP_USER)) {
189 	case PMC_CAP_SYSTEM:
190 		config |= PMEVTYPER_U;
191 		break;
192 	case PMC_CAP_USER:
193 		config |= PMEVTYPER_P;
194 		break;
195 	default:
196 		/*
197 		 * Trace both USER and SYSTEM if none are specified
198 		 * (default setting) or if both flags are specified
199 		 * (user explicitly requested both qualifiers).
200 		 */
201 		break;
202 	}
203 
204 	pm->pm_md.pm_arm64.pm_arm64_evsel = config;
205 	PMCDBG2(MDP, ALL, 2, "arm64-allocate ri=%d -> config=0x%x", ri, config);
206 
207 	return (0);
208 }
209 
210 
211 static int
212 arm64_read_pmc(int cpu, int ri, pmc_value_t *v)
213 {
214 	pmc_value_t tmp;
215 	struct pmc *pm;
216 	register_t s;
217 	int reg;
218 
219 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
220 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
221 	KASSERT(ri >= 0 && ri < arm64_npmcs,
222 	    ("[arm64,%d] illegal row index %d", __LINE__, ri));
223 
224 	pm  = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
225 
226 	/*
227 	 * Ensure we don't get interrupted while updating the overflow count.
228 	 */
229 	s = intr_disable();
230 	tmp = arm64_pmcn_read(ri);
231 	reg = (1 << ri);
232 	if ((READ_SPECIALREG(pmovsclr_el0) & reg) != 0) {
233 		/* Clear Overflow Flag */
234 		WRITE_SPECIALREG(pmovsclr_el0, reg);
235 		pm->pm_pcpu_state[cpu].pps_overflowcnt++;
236 
237 		/* Reread counter in case we raced. */
238 		tmp = arm64_pmcn_read(ri);
239 	}
240 	tmp += 0x100000000llu * pm->pm_pcpu_state[cpu].pps_overflowcnt;
241 	intr_restore(s);
242 
243 	PMCDBG2(MDP, REA, 2, "arm64-read id=%d -> %jd", ri, tmp);
244 	if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) {
245 		/*
246 		 * Clamp value to 0 if the counter just overflowed,
247 		 * otherwise the returned reload count would wrap to a
248 		 * huge value.
249 		 */
250 		if ((tmp & (1ull << 63)) == 0)
251 			tmp = 0;
252 		else
253 			tmp = ARMV8_PERFCTR_VALUE_TO_RELOAD_COUNT(tmp);
254 	}
255 	*v = tmp;
256 
257 	return (0);
258 }
259 
260 static int
261 arm64_write_pmc(int cpu, int ri, pmc_value_t v)
262 {
263 	struct pmc *pm;
264 
265 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
266 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
267 	KASSERT(ri >= 0 && ri < arm64_npmcs,
268 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
269 
270 	pm  = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
271 
272 	if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
273 		v = ARMV8_RELOAD_COUNT_TO_PERFCTR_VALUE(v);
274 
275 	PMCDBG3(MDP, WRI, 1, "arm64-write cpu=%d ri=%d v=%jx", cpu, ri, v);
276 
277 	pm->pm_pcpu_state[cpu].pps_overflowcnt = v >> 32;
278 	arm64_pmcn_write(ri, v);
279 
280 	return (0);
281 }
282 
283 static int
284 arm64_config_pmc(int cpu, int ri, struct pmc *pm)
285 {
286 	struct pmc_hw *phw;
287 
288 	PMCDBG3(MDP, CFG, 1, "cpu=%d ri=%d pm=%p", cpu, ri, pm);
289 
290 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
291 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
292 	KASSERT(ri >= 0 && ri < arm64_npmcs,
293 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
294 
295 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
296 
297 	KASSERT(pm == NULL || phw->phw_pmc == NULL,
298 	    ("[arm64,%d] pm=%p phw->pm=%p hwpmc not unconfigured",
299 	    __LINE__, pm, phw->phw_pmc));
300 
301 	phw->phw_pmc = pm;
302 
303 	return (0);
304 }
305 
306 static int
307 arm64_start_pmc(int cpu, int ri)
308 {
309 	struct pmc_hw *phw;
310 	uint32_t config;
311 	struct pmc *pm;
312 
313 	phw    = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
314 	pm     = phw->phw_pmc;
315 	config = pm->pm_md.pm_arm64.pm_arm64_evsel;
316 
317 	/*
318 	 * Configure the event selection.
319 	 */
320 	WRITE_SPECIALREG(pmselr_el0, ri);
321 	WRITE_SPECIALREG(pmxevtyper_el0, config);
322 
323 	isb();
324 
325 	/*
326 	 * Enable the PMC.
327 	 */
328 	arm64_interrupt_enable(ri);
329 	arm64_counter_enable(ri);
330 
331 	return (0);
332 }
333 
334 static int
335 arm64_stop_pmc(int cpu, int ri)
336 {
337 	/*
338 	 * Disable the PMCs.
339 	 */
340 	arm64_counter_disable(ri);
341 	arm64_interrupt_disable(ri);
342 
343 	return (0);
344 }
345 
346 static int
347 arm64_release_pmc(int cpu, int ri, struct pmc *pmc)
348 {
349 	struct pmc_hw *phw;
350 
351 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
352 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
353 	KASSERT(ri >= 0 && ri < arm64_npmcs,
354 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
355 
356 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
357 	KASSERT(phw->phw_pmc == NULL,
358 	    ("[arm64,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
359 
360 	return (0);
361 }
362 
363 static int
364 arm64_intr(struct trapframe *tf)
365 {
366 	int retval, ri;
367 	struct pmc *pm;
368 	int error;
369 	int reg, cpu;
370 
371 	cpu = curcpu;
372 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
373 	    ("[arm64,%d] CPU %d out of range", __LINE__, cpu));
374 
375 	PMCDBG3(MDP,INT,1, "cpu=%d tf=%p um=%d", cpu, (void *)tf,
376 	    TRAPF_USERMODE(tf));
377 
378 	retval = 0;
379 
380 	for (ri = 0; ri < arm64_npmcs; ri++) {
381 		pm = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
382 		if (pm == NULL)
383 			continue;
384 		/* Check if counter is overflowed */
385 		reg = (1 << ri);
386 		if ((READ_SPECIALREG(pmovsclr_el0) & reg) == 0)
387 			continue;
388 		/* Clear Overflow Flag */
389 		WRITE_SPECIALREG(pmovsclr_el0, reg);
390 
391 		isb();
392 
393 		retval = 1; /* Found an interrupting PMC. */
394 
395 		pm->pm_pcpu_state[cpu].pps_overflowcnt += 1;
396 
397 		if (!PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
398 			continue;
399 
400 		if (pm->pm_state != PMC_STATE_RUNNING)
401 			continue;
402 
403 		error = pmc_process_interrupt(PMC_HR, pm, tf);
404 		if (error)
405 			arm64_stop_pmc(cpu, ri);
406 
407 		/* Reload sampling count */
408 		arm64_write_pmc(cpu, ri, pm->pm_sc.pm_reloadcount);
409 	}
410 
411 	return (retval);
412 }
413 
414 static int
415 arm64_describe(int cpu, int ri, struct pmc_info *pi, struct pmc **ppmc)
416 {
417 	char arm64_name[PMC_NAME_MAX];
418 	struct pmc_hw *phw;
419 	int error;
420 
421 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
422 	    ("[arm64,%d], illegal CPU %d", __LINE__, cpu));
423 	KASSERT(ri >= 0 && ri < arm64_npmcs,
424 	    ("[arm64,%d] row-index %d out of range", __LINE__, ri));
425 
426 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
427 	snprintf(arm64_name, sizeof(arm64_name), "ARMV8-%d", ri);
428 	if ((error = copystr(arm64_name, pi->pm_name, PMC_NAME_MAX,
429 	    NULL)) != 0)
430 		return (error);
431 	pi->pm_class = PMC_CLASS_ARMV8;
432 	if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
433 		pi->pm_enabled = TRUE;
434 		*ppmc = phw->phw_pmc;
435 	} else {
436 		pi->pm_enabled = FALSE;
437 		*ppmc = NULL;
438 	}
439 
440 	return (0);
441 }
442 
443 static int
444 arm64_get_config(int cpu, int ri, struct pmc **ppm)
445 {
446 
447 	*ppm = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
448 
449 	return (0);
450 }
451 
452 /*
453  * XXX don't know what we should do here.
454  */
455 static int
456 arm64_switch_in(struct pmc_cpu *pc, struct pmc_process *pp)
457 {
458 
459 	return (0);
460 }
461 
462 static int
463 arm64_switch_out(struct pmc_cpu *pc, struct pmc_process *pp)
464 {
465 
466 	return (0);
467 }
468 
469 static int
470 arm64_pcpu_init(struct pmc_mdep *md, int cpu)
471 {
472 	struct arm64_cpu *pac;
473 	struct pmc_hw  *phw;
474 	struct pmc_cpu *pc;
475 	uint64_t pmcr;
476 	int first_ri;
477 	int i;
478 
479 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
480 	    ("[arm64,%d] wrong cpu number %d", __LINE__, cpu));
481 	PMCDBG1(MDP, INI, 1, "arm64-init cpu=%d", cpu);
482 
483 	arm64_pcpu[cpu] = pac = malloc(sizeof(struct arm64_cpu), M_PMC,
484 	    M_WAITOK | M_ZERO);
485 
486 	pac->pc_arm64pmcs = malloc(sizeof(struct pmc_hw) * arm64_npmcs,
487 	    M_PMC, M_WAITOK | M_ZERO);
488 	pc = pmc_pcpu[cpu];
489 	first_ri = md->pmd_classdep[PMC_MDEP_CLASS_INDEX_ARMV8].pcd_ri;
490 	KASSERT(pc != NULL, ("[arm64,%d] NULL per-cpu pointer", __LINE__));
491 
492 	for (i = 0, phw = pac->pc_arm64pmcs; i < arm64_npmcs; i++, phw++) {
493 		phw->phw_state    = PMC_PHW_FLAG_IS_ENABLED |
494 		    PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(i);
495 		phw->phw_pmc      = NULL;
496 		pc->pc_hwpmcs[i + first_ri] = phw;
497 	}
498 
499 	/*
500 	 * Disable all counters and overflow interrupts. Upon reset they are in
501 	 * an undefined state.
502 	 *
503 	 * Don't issue an isb here, just wait for the one in arm64_pmcr_write()
504 	 * to make the writes visible.
505 	 */
506 	WRITE_SPECIALREG(pmcntenclr_el0, 0xffffffff);
507 	WRITE_SPECIALREG(pmintenclr_el1, 0xffffffff);
508 
509 	/* Enable unit */
510 	pmcr = arm64_pmcr_read();
511 	pmcr |= PMCR_E;
512 	arm64_pmcr_write(pmcr);
513 
514 	return (0);
515 }
516 
517 static int
518 arm64_pcpu_fini(struct pmc_mdep *md, int cpu)
519 {
520 	uint32_t pmcr;
521 
522 	pmcr = arm64_pmcr_read();
523 	pmcr &= ~PMCR_E;
524 	arm64_pmcr_write(pmcr);
525 
526 	return (0);
527 }
528 
529 struct pmc_mdep *
530 pmc_arm64_initialize()
531 {
532 	struct pmc_mdep *pmc_mdep;
533 	struct pmc_classdep *pcd;
534 	int idcode, impcode;
535 	int reg;
536 	uint64_t midr;
537 
538 	reg = arm64_pmcr_read();
539 	arm64_npmcs = (reg & PMCR_N_MASK) >> PMCR_N_SHIFT;
540 	impcode = (reg & PMCR_IMP_MASK) >> PMCR_IMP_SHIFT;
541 	idcode = (reg & PMCR_IDCODE_MASK) >> PMCR_IDCODE_SHIFT;
542 
543 	PMCDBG1(MDP, INI, 1, "arm64-init npmcs=%d", arm64_npmcs);
544 
545 	/*
546 	 * Write the CPU model to kern.hwpmc.cpuid.
547 	 *
548 	 * We zero the variant and revision fields.
549 	 *
550 	 * TODO: how to handle differences between cores due to big.LITTLE?
551 	 * For now, just use MIDR from CPU 0.
552 	 */
553 	midr = (uint64_t)(pcpu_find(0)->pc_midr);
554 	midr &= ~(CPU_VAR_MASK | CPU_REV_MASK);
555 	snprintf(pmc_cpuid, sizeof(pmc_cpuid), "0x%016lx", midr);
556 
557 	/*
558 	 * Allocate space for pointers to PMC HW descriptors and for
559 	 * the MDEP structure used by MI code.
560 	 */
561 	arm64_pcpu = malloc(sizeof(struct arm64_cpu *) * pmc_cpu_max(),
562 		M_PMC, M_WAITOK | M_ZERO);
563 
564 	/* Just one class */
565 	pmc_mdep = pmc_mdep_alloc(1);
566 
567 	switch(impcode) {
568 	case PMCR_IMP_ARM:
569 		switch (idcode) {
570 		case PMCR_IDCODE_CORTEX_A76:
571 		case PMCR_IDCODE_NEOVERSE_N1:
572 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A76;
573 			break;
574 		case PMCR_IDCODE_CORTEX_A57:
575 		case PMCR_IDCODE_CORTEX_A72:
576 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A57;
577 			break;
578 		default:
579 		case PMCR_IDCODE_CORTEX_A53:
580 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A53;
581 			break;
582 		}
583 		break;
584 	default:
585 		pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A53;
586 		break;
587 	}
588 
589 	pcd = &pmc_mdep->pmd_classdep[PMC_MDEP_CLASS_INDEX_ARMV8];
590 	pcd->pcd_caps  = ARMV8_PMC_CAPS;
591 	pcd->pcd_class = PMC_CLASS_ARMV8;
592 	pcd->pcd_num   = arm64_npmcs;
593 	pcd->pcd_ri    = pmc_mdep->pmd_npmc;
594 	pcd->pcd_width = 32;
595 
596 	pcd->pcd_allocate_pmc   = arm64_allocate_pmc;
597 	pcd->pcd_config_pmc     = arm64_config_pmc;
598 	pcd->pcd_pcpu_fini      = arm64_pcpu_fini;
599 	pcd->pcd_pcpu_init      = arm64_pcpu_init;
600 	pcd->pcd_describe       = arm64_describe;
601 	pcd->pcd_get_config     = arm64_get_config;
602 	pcd->pcd_read_pmc       = arm64_read_pmc;
603 	pcd->pcd_release_pmc    = arm64_release_pmc;
604 	pcd->pcd_start_pmc      = arm64_start_pmc;
605 	pcd->pcd_stop_pmc       = arm64_stop_pmc;
606 	pcd->pcd_write_pmc      = arm64_write_pmc;
607 
608 	pmc_mdep->pmd_intr       = arm64_intr;
609 	pmc_mdep->pmd_switch_in  = arm64_switch_in;
610 	pmc_mdep->pmd_switch_out = arm64_switch_out;
611 
612 	pmc_mdep->pmd_npmc   += arm64_npmcs;
613 
614 	return (pmc_mdep);
615 }
616 
617 void
618 pmc_arm64_finalize(struct pmc_mdep *md)
619 {
620 
621 }
622