xref: /freebsd/sys/dev/hwpmc/hwpmc_arm64.c (revision b3b50e64d7e4c28bd0fd6323591ed811633826e4)
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 	struct arm64_cpu *pac;
169 	enum pmc_event pe;
170 
171 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
172 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
173 	KASSERT(ri >= 0 && ri < arm64_npmcs,
174 	    ("[arm64,%d] illegal row index %d", __LINE__, ri));
175 
176 	pac = arm64_pcpu[cpu];
177 
178 	if (a->pm_class != PMC_CLASS_ARMV8) {
179 		return (EINVAL);
180 	}
181 	pe = a->pm_ev;
182 
183 	/* Adjust the config value if needed. */
184 	config = a->pm_md.pm_md_config;
185 	if ((a->pm_md.pm_md_flags & PM_MD_RAW_EVENT) == 0) {
186 		config = (uint32_t)pe - PMC_EV_ARMV8_FIRST;
187 		if (config > (PMC_EV_ARMV8_LAST - PMC_EV_ARMV8_FIRST))
188 			return (EINVAL);
189 	}
190 
191 	switch (a->pm_caps & (PMC_CAP_SYSTEM | PMC_CAP_USER)) {
192 	case PMC_CAP_SYSTEM:
193 		config |= PMEVTYPER_U;
194 		break;
195 	case PMC_CAP_USER:
196 		config |= PMEVTYPER_P;
197 		break;
198 	default:
199 		/*
200 		 * Trace both USER and SYSTEM if none are specified
201 		 * (default setting) or if both flags are specified
202 		 * (user explicitly requested both qualifiers).
203 		 */
204 		break;
205 	}
206 
207 	pm->pm_md.pm_arm64.pm_arm64_evsel = config;
208 	PMCDBG2(MDP, ALL, 2, "arm64-allocate ri=%d -> config=0x%x", ri, config);
209 
210 	return (0);
211 }
212 
213 
214 static int
215 arm64_read_pmc(int cpu, int ri, pmc_value_t *v)
216 {
217 	pmc_value_t tmp;
218 	struct pmc *pm;
219 	register_t s;
220 	int reg;
221 
222 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
223 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
224 	KASSERT(ri >= 0 && ri < arm64_npmcs,
225 	    ("[arm64,%d] illegal row index %d", __LINE__, ri));
226 
227 	pm  = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
228 
229 	/*
230 	 * Ensure we don't get interrupted while updating the overflow count.
231 	 */
232 	s = intr_disable();
233 	tmp = arm64_pmcn_read(ri);
234 	reg = (1 << ri);
235 	if ((READ_SPECIALREG(pmovsclr_el0) & reg) != 0) {
236 		/* Clear Overflow Flag */
237 		WRITE_SPECIALREG(pmovsclr_el0, reg);
238 		pm->pm_pcpu_state[cpu].pps_overflowcnt++;
239 
240 		/* Reread counter in case we raced. */
241 		tmp = arm64_pmcn_read(ri);
242 	}
243 	tmp += 0x100000000llu * pm->pm_pcpu_state[cpu].pps_overflowcnt;
244 	intr_restore(s);
245 
246 	PMCDBG2(MDP, REA, 2, "arm64-read id=%d -> %jd", ri, tmp);
247 	if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) {
248 		/*
249 		 * Clamp value to 0 if the counter just overflowed,
250 		 * otherwise the returned reload count would wrap to a
251 		 * huge value.
252 		 */
253 		if ((tmp & (1ull << 63)) == 0)
254 			tmp = 0;
255 		else
256 			tmp = ARMV8_PERFCTR_VALUE_TO_RELOAD_COUNT(tmp);
257 	}
258 	*v = tmp;
259 
260 	return (0);
261 }
262 
263 static int
264 arm64_write_pmc(int cpu, int ri, pmc_value_t v)
265 {
266 	struct pmc *pm;
267 
268 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
269 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
270 	KASSERT(ri >= 0 && ri < arm64_npmcs,
271 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
272 
273 	pm  = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
274 
275 	if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
276 		v = ARMV8_RELOAD_COUNT_TO_PERFCTR_VALUE(v);
277 
278 	PMCDBG3(MDP, WRI, 1, "arm64-write cpu=%d ri=%d v=%jx", cpu, ri, v);
279 
280 	pm->pm_pcpu_state[cpu].pps_overflowcnt = v >> 32;
281 	arm64_pmcn_write(ri, v);
282 
283 	return (0);
284 }
285 
286 static int
287 arm64_config_pmc(int cpu, int ri, struct pmc *pm)
288 {
289 	struct pmc_hw *phw;
290 
291 	PMCDBG3(MDP, CFG, 1, "cpu=%d ri=%d pm=%p", cpu, ri, pm);
292 
293 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
294 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
295 	KASSERT(ri >= 0 && ri < arm64_npmcs,
296 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
297 
298 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
299 
300 	KASSERT(pm == NULL || phw->phw_pmc == NULL,
301 	    ("[arm64,%d] pm=%p phw->pm=%p hwpmc not unconfigured",
302 	    __LINE__, pm, phw->phw_pmc));
303 
304 	phw->phw_pmc = pm;
305 
306 	return (0);
307 }
308 
309 static int
310 arm64_start_pmc(int cpu, int ri)
311 {
312 	struct pmc_hw *phw;
313 	uint32_t config;
314 	struct pmc *pm;
315 
316 	phw    = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
317 	pm     = phw->phw_pmc;
318 	config = pm->pm_md.pm_arm64.pm_arm64_evsel;
319 
320 	/*
321 	 * Configure the event selection.
322 	 */
323 	WRITE_SPECIALREG(pmselr_el0, ri);
324 	WRITE_SPECIALREG(pmxevtyper_el0, config);
325 
326 	isb();
327 
328 	/*
329 	 * Enable the PMC.
330 	 */
331 	arm64_interrupt_enable(ri);
332 	arm64_counter_enable(ri);
333 
334 	return (0);
335 }
336 
337 static int
338 arm64_stop_pmc(int cpu, int ri)
339 {
340 	struct pmc_hw *phw;
341 	struct pmc *pm;
342 
343 	phw    = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
344 	pm     = phw->phw_pmc;
345 
346 	/*
347 	 * Disable the PMCs.
348 	 */
349 	arm64_counter_disable(ri);
350 	arm64_interrupt_disable(ri);
351 
352 	return (0);
353 }
354 
355 static int
356 arm64_release_pmc(int cpu, int ri, struct pmc *pmc)
357 {
358 	struct pmc_hw *phw;
359 
360 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
361 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
362 	KASSERT(ri >= 0 && ri < arm64_npmcs,
363 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
364 
365 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
366 	KASSERT(phw->phw_pmc == NULL,
367 	    ("[arm64,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
368 
369 	return (0);
370 }
371 
372 static int
373 arm64_intr(struct trapframe *tf)
374 {
375 	struct arm64_cpu *pc;
376 	int retval, ri;
377 	struct pmc *pm;
378 	int error;
379 	int reg, cpu;
380 
381 	cpu = curcpu;
382 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
383 	    ("[arm64,%d] CPU %d out of range", __LINE__, cpu));
384 
385 	PMCDBG3(MDP,INT,1, "cpu=%d tf=%p um=%d", cpu, (void *)tf,
386 	    TRAPF_USERMODE(tf));
387 
388 	retval = 0;
389 	pc = arm64_pcpu[cpu];
390 
391 	for (ri = 0; ri < arm64_npmcs; ri++) {
392 		pm = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
393 		if (pm == NULL)
394 			continue;
395 		/* Check if counter is overflowed */
396 		reg = (1 << ri);
397 		if ((READ_SPECIALREG(pmovsclr_el0) & reg) == 0)
398 			continue;
399 		/* Clear Overflow Flag */
400 		WRITE_SPECIALREG(pmovsclr_el0, reg);
401 
402 		isb();
403 
404 		retval = 1; /* Found an interrupting PMC. */
405 
406 		pm->pm_pcpu_state[cpu].pps_overflowcnt += 1;
407 
408 		if (!PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
409 			continue;
410 
411 		if (pm->pm_state != PMC_STATE_RUNNING)
412 			continue;
413 
414 		error = pmc_process_interrupt(PMC_HR, pm, tf);
415 		if (error)
416 			arm64_stop_pmc(cpu, ri);
417 
418 		/* Reload sampling count */
419 		arm64_write_pmc(cpu, ri, pm->pm_sc.pm_reloadcount);
420 	}
421 
422 	return (retval);
423 }
424 
425 static int
426 arm64_describe(int cpu, int ri, struct pmc_info *pi, struct pmc **ppmc)
427 {
428 	char arm64_name[PMC_NAME_MAX];
429 	struct pmc_hw *phw;
430 	int error;
431 
432 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
433 	    ("[arm64,%d], illegal CPU %d", __LINE__, cpu));
434 	KASSERT(ri >= 0 && ri < arm64_npmcs,
435 	    ("[arm64,%d] row-index %d out of range", __LINE__, ri));
436 
437 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
438 	snprintf(arm64_name, sizeof(arm64_name), "ARMV8-%d", ri);
439 	if ((error = copystr(arm64_name, pi->pm_name, PMC_NAME_MAX,
440 	    NULL)) != 0)
441 		return (error);
442 	pi->pm_class = PMC_CLASS_ARMV8;
443 	if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
444 		pi->pm_enabled = TRUE;
445 		*ppmc = phw->phw_pmc;
446 	} else {
447 		pi->pm_enabled = FALSE;
448 		*ppmc = NULL;
449 	}
450 
451 	return (0);
452 }
453 
454 static int
455 arm64_get_config(int cpu, int ri, struct pmc **ppm)
456 {
457 
458 	*ppm = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
459 
460 	return (0);
461 }
462 
463 /*
464  * XXX don't know what we should do here.
465  */
466 static int
467 arm64_switch_in(struct pmc_cpu *pc, struct pmc_process *pp)
468 {
469 
470 	return (0);
471 }
472 
473 static int
474 arm64_switch_out(struct pmc_cpu *pc, struct pmc_process *pp)
475 {
476 
477 	return (0);
478 }
479 
480 static int
481 arm64_pcpu_init(struct pmc_mdep *md, int cpu)
482 {
483 	struct arm64_cpu *pac;
484 	struct pmc_hw  *phw;
485 	struct pmc_cpu *pc;
486 	uint64_t pmcr;
487 	int first_ri;
488 	int i;
489 
490 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
491 	    ("[arm64,%d] wrong cpu number %d", __LINE__, cpu));
492 	PMCDBG1(MDP, INI, 1, "arm64-init cpu=%d", cpu);
493 
494 	arm64_pcpu[cpu] = pac = malloc(sizeof(struct arm64_cpu), M_PMC,
495 	    M_WAITOK | M_ZERO);
496 
497 	pac->pc_arm64pmcs = malloc(sizeof(struct pmc_hw) * arm64_npmcs,
498 	    M_PMC, M_WAITOK | M_ZERO);
499 	pc = pmc_pcpu[cpu];
500 	first_ri = md->pmd_classdep[PMC_MDEP_CLASS_INDEX_ARMV8].pcd_ri;
501 	KASSERT(pc != NULL, ("[arm64,%d] NULL per-cpu pointer", __LINE__));
502 
503 	for (i = 0, phw = pac->pc_arm64pmcs; i < arm64_npmcs; i++, phw++) {
504 		phw->phw_state    = PMC_PHW_FLAG_IS_ENABLED |
505 		    PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(i);
506 		phw->phw_pmc      = NULL;
507 		pc->pc_hwpmcs[i + first_ri] = phw;
508 	}
509 
510 	/*
511 	 * Disable all counters and overflow interrupts. Upon reset they are in
512 	 * an undefined state.
513 	 *
514 	 * Don't issue an isb here, just wait for the one in arm64_pmcr_write()
515 	 * to make the writes visible.
516 	 */
517 	WRITE_SPECIALREG(pmcntenclr_el0, 0xffffffff);
518 	WRITE_SPECIALREG(pmintenclr_el1, 0xffffffff);
519 
520 	/* Enable unit */
521 	pmcr = arm64_pmcr_read();
522 	pmcr |= PMCR_E;
523 	arm64_pmcr_write(pmcr);
524 
525 	return (0);
526 }
527 
528 static int
529 arm64_pcpu_fini(struct pmc_mdep *md, int cpu)
530 {
531 	uint32_t pmcr;
532 
533 	pmcr = arm64_pmcr_read();
534 	pmcr &= ~PMCR_E;
535 	arm64_pmcr_write(pmcr);
536 
537 	return (0);
538 }
539 
540 struct pmc_mdep *
541 pmc_arm64_initialize()
542 {
543 	struct pmc_mdep *pmc_mdep;
544 	struct pmc_classdep *pcd;
545 	int idcode, impcode;
546 	int reg;
547 	uint64_t midr;
548 
549 	reg = arm64_pmcr_read();
550 	arm64_npmcs = (reg & PMCR_N_MASK) >> PMCR_N_SHIFT;
551 	impcode = (reg & PMCR_IMP_MASK) >> PMCR_IMP_SHIFT;
552 	idcode = (reg & PMCR_IDCODE_MASK) >> PMCR_IDCODE_SHIFT;
553 
554 	PMCDBG1(MDP, INI, 1, "arm64-init npmcs=%d", arm64_npmcs);
555 
556 	/*
557 	 * Write the CPU model to kern.hwpmc.cpuid.
558 	 *
559 	 * We zero the variant and revision fields.
560 	 *
561 	 * TODO: how to handle differences between cores due to big.LITTLE?
562 	 * For now, just use MIDR from CPU 0.
563 	 */
564 	midr = (uint64_t)(pcpu_find(0)->pc_midr);
565 	midr &= ~(CPU_VAR_MASK | CPU_REV_MASK);
566 	snprintf(pmc_cpuid, sizeof(pmc_cpuid), "0x%016lx", midr);
567 
568 	/*
569 	 * Allocate space for pointers to PMC HW descriptors and for
570 	 * the MDEP structure used by MI code.
571 	 */
572 	arm64_pcpu = malloc(sizeof(struct arm64_cpu *) * pmc_cpu_max(),
573 		M_PMC, M_WAITOK | M_ZERO);
574 
575 	/* Just one class */
576 	pmc_mdep = pmc_mdep_alloc(1);
577 
578 	switch(impcode) {
579 	case PMCR_IMP_ARM:
580 		switch (idcode) {
581 		case PMCR_IDCODE_CORTEX_A76:
582 		case PMCR_IDCODE_NEOVERSE_N1:
583 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A76;
584 			break;
585 		case PMCR_IDCODE_CORTEX_A57:
586 		case PMCR_IDCODE_CORTEX_A72:
587 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A57;
588 			break;
589 		default:
590 		case PMCR_IDCODE_CORTEX_A53:
591 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A53;
592 			break;
593 		}
594 		break;
595 	default:
596 		pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A53;
597 		break;
598 	}
599 
600 	pcd = &pmc_mdep->pmd_classdep[PMC_MDEP_CLASS_INDEX_ARMV8];
601 	pcd->pcd_caps  = ARMV8_PMC_CAPS;
602 	pcd->pcd_class = PMC_CLASS_ARMV8;
603 	pcd->pcd_num   = arm64_npmcs;
604 	pcd->pcd_ri    = pmc_mdep->pmd_npmc;
605 	pcd->pcd_width = 32;
606 
607 	pcd->pcd_allocate_pmc   = arm64_allocate_pmc;
608 	pcd->pcd_config_pmc     = arm64_config_pmc;
609 	pcd->pcd_pcpu_fini      = arm64_pcpu_fini;
610 	pcd->pcd_pcpu_init      = arm64_pcpu_init;
611 	pcd->pcd_describe       = arm64_describe;
612 	pcd->pcd_get_config     = arm64_get_config;
613 	pcd->pcd_read_pmc       = arm64_read_pmc;
614 	pcd->pcd_release_pmc    = arm64_release_pmc;
615 	pcd->pcd_start_pmc      = arm64_start_pmc;
616 	pcd->pcd_stop_pmc       = arm64_stop_pmc;
617 	pcd->pcd_write_pmc      = arm64_write_pmc;
618 
619 	pmc_mdep->pmd_intr       = arm64_intr;
620 	pmc_mdep->pmd_switch_in  = arm64_switch_in;
621 	pmc_mdep->pmd_switch_out = arm64_switch_out;
622 
623 	pmc_mdep->pmd_npmc   += arm64_npmcs;
624 
625 	return (pmc_mdep);
626 }
627 
628 void
629 pmc_arm64_finalize(struct pmc_mdep *md)
630 {
631 
632 }
633