xref: /freebsd/sys/dev/hwpmc/hwpmc_arm64.c (revision 397e83df75e0fcd0d3fcb95ae4d794cb7600fc89)
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/param.h>
31 #include <sys/systm.h>
32 #include <sys/pmc.h>
33 #include <sys/pmckern.h>
34 
35 #include <machine/pmc_mdep.h>
36 #include <machine/cpu.h>
37 
38 #include "opt_acpi.h"
39 
40 static int arm64_npmcs;
41 
42 struct arm64_event_code_map {
43 	enum pmc_event	pe_ev;
44 	uint8_t		pe_code;
45 };
46 
47 /*
48  * Per-processor information.
49  */
50 struct arm64_cpu {
51 	struct pmc_hw   *pc_arm64pmcs;
52 };
53 
54 static struct arm64_cpu **arm64_pcpu;
55 
56 /*
57  * Interrupt Enable Set Register
58  */
59 static __inline void
60 arm64_interrupt_enable(uint32_t pmc)
61 {
62 	uint32_t reg;
63 
64 	reg = (1 << pmc);
65 	WRITE_SPECIALREG(pmintenset_el1, reg);
66 
67 	isb();
68 }
69 
70 /*
71  * Interrupt Clear Set Register
72  */
73 static __inline void
74 arm64_interrupt_disable(uint32_t pmc)
75 {
76 	uint32_t reg;
77 
78 	reg = (1 << pmc);
79 	WRITE_SPECIALREG(pmintenclr_el1, reg);
80 
81 	isb();
82 }
83 
84 /*
85  * Counter Set Enable Register
86  */
87 static __inline void
88 arm64_counter_enable(unsigned int pmc)
89 {
90 	uint32_t reg;
91 
92 	reg = (1 << pmc);
93 	WRITE_SPECIALREG(pmcntenset_el0, reg);
94 
95 	isb();
96 }
97 
98 /*
99  * Counter Clear Enable Register
100  */
101 static __inline void
102 arm64_counter_disable(unsigned int pmc)
103 {
104 	uint32_t reg;
105 
106 	reg = (1 << pmc);
107 	WRITE_SPECIALREG(pmcntenclr_el0, reg);
108 
109 	isb();
110 }
111 
112 /*
113  * Performance Monitors Control Register
114  */
115 static uint32_t
116 arm64_pmcr_read(void)
117 {
118 	uint32_t reg;
119 
120 	reg = READ_SPECIALREG(pmcr_el0);
121 
122 	return (reg);
123 }
124 
125 static void
126 arm64_pmcr_write(uint32_t reg)
127 {
128 
129 	WRITE_SPECIALREG(pmcr_el0, reg);
130 
131 	isb();
132 }
133 
134 /*
135  * Performance Count Register N
136  */
137 static uint32_t
138 arm64_pmcn_read(unsigned int pmc)
139 {
140 
141 	KASSERT(pmc < arm64_npmcs, ("%s: illegal PMC number %d", __func__, pmc));
142 
143 	WRITE_SPECIALREG(pmselr_el0, pmc);
144 
145 	isb();
146 
147 	return (READ_SPECIALREG(pmxevcntr_el0));
148 }
149 
150 static void
151 arm64_pmcn_write(unsigned int pmc, uint32_t reg)
152 {
153 
154 	KASSERT(pmc < arm64_npmcs, ("%s: illegal PMC number %d", __func__, pmc));
155 
156 	WRITE_SPECIALREG(pmselr_el0, pmc);
157 	WRITE_SPECIALREG(pmxevcntr_el0, reg);
158 
159 	isb();
160 }
161 
162 static int
163 arm64_allocate_pmc(int cpu, int ri, struct pmc *pm,
164   const struct pmc_op_pmcallocate *a)
165 {
166 	uint32_t config;
167 	enum pmc_event pe;
168 
169 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
170 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
171 	KASSERT(ri >= 0 && ri < arm64_npmcs,
172 	    ("[arm64,%d] illegal row index %d", __LINE__, ri));
173 
174 	if (a->pm_class != PMC_CLASS_ARMV8) {
175 		return (EINVAL);
176 	}
177 	pe = a->pm_ev;
178 
179 	if ((a->pm_flags & PMC_F_EV_PMU) != 0) {
180 		config = a->pm_md.pm_md_config;
181 	} else {
182 		config = (uint32_t)pe - PMC_EV_ARMV8_FIRST;
183 		if (config > (PMC_EV_ARMV8_LAST - PMC_EV_ARMV8_FIRST))
184 			return (EINVAL);
185 	}
186 
187 	switch (a->pm_caps & (PMC_CAP_SYSTEM | PMC_CAP_USER)) {
188 	case PMC_CAP_SYSTEM:
189 		config |= PMEVTYPER_U;
190 		break;
191 	case PMC_CAP_USER:
192 		config |= PMEVTYPER_P;
193 		break;
194 	default:
195 		/*
196 		 * Trace both USER and SYSTEM if none are specified
197 		 * (default setting) or if both flags are specified
198 		 * (user explicitly requested both qualifiers).
199 		 */
200 		break;
201 	}
202 
203 	pm->pm_md.pm_arm64.pm_arm64_evsel = config;
204 	PMCDBG2(MDP, ALL, 2, "arm64-allocate ri=%d -> config=0x%x", ri, config);
205 
206 	return (0);
207 }
208 
209 
210 static int
211 arm64_read_pmc(int cpu, int ri, struct pmc *pm, pmc_value_t *v)
212 {
213 	pmc_value_t tmp;
214 	register_t s;
215 	int reg;
216 
217 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
218 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
219 	KASSERT(ri >= 0 && ri < arm64_npmcs,
220 	    ("[arm64,%d] illegal row index %d", __LINE__, ri));
221 
222 	/*
223 	 * Ensure we don't get interrupted while updating the overflow count.
224 	 */
225 	s = intr_disable();
226 	tmp = arm64_pmcn_read(ri);
227 	reg = (1 << ri);
228 	if ((READ_SPECIALREG(pmovsclr_el0) & reg) != 0) {
229 		/* Clear Overflow Flag */
230 		WRITE_SPECIALREG(pmovsclr_el0, reg);
231 		pm->pm_pcpu_state[cpu].pps_overflowcnt++;
232 
233 		/* Reread counter in case we raced. */
234 		tmp = arm64_pmcn_read(ri);
235 	}
236 	tmp += 0x100000000llu * pm->pm_pcpu_state[cpu].pps_overflowcnt;
237 	intr_restore(s);
238 
239 	PMCDBG2(MDP, REA, 2, "arm64-read id=%d -> %jd", ri, tmp);
240 	if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) {
241 		/*
242 		 * Clamp value to 0 if the counter just overflowed,
243 		 * otherwise the returned reload count would wrap to a
244 		 * huge value.
245 		 */
246 		if ((tmp & (1ull << 63)) == 0)
247 			tmp = 0;
248 		else
249 			tmp = ARMV8_PERFCTR_VALUE_TO_RELOAD_COUNT(tmp);
250 	}
251 	*v = tmp;
252 
253 	return (0);
254 }
255 
256 static int
257 arm64_write_pmc(int cpu, int ri, struct pmc *pm, pmc_value_t v)
258 {
259 
260 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
261 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
262 	KASSERT(ri >= 0 && ri < arm64_npmcs,
263 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
264 
265 	if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
266 		v = ARMV8_RELOAD_COUNT_TO_PERFCTR_VALUE(v);
267 
268 	PMCDBG3(MDP, WRI, 1, "arm64-write cpu=%d ri=%d v=%jx", cpu, ri, v);
269 
270 	pm->pm_pcpu_state[cpu].pps_overflowcnt = v >> 32;
271 	arm64_pmcn_write(ri, v);
272 
273 	return (0);
274 }
275 
276 static int
277 arm64_config_pmc(int cpu, int ri, struct pmc *pm)
278 {
279 	struct pmc_hw *phw;
280 
281 	PMCDBG3(MDP, CFG, 1, "cpu=%d ri=%d pm=%p", cpu, ri, pm);
282 
283 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
284 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
285 	KASSERT(ri >= 0 && ri < arm64_npmcs,
286 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
287 
288 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
289 
290 	KASSERT(pm == NULL || phw->phw_pmc == NULL,
291 	    ("[arm64,%d] pm=%p phw->pm=%p hwpmc not unconfigured",
292 	    __LINE__, pm, phw->phw_pmc));
293 
294 	phw->phw_pmc = pm;
295 
296 	return (0);
297 }
298 
299 static int
300 arm64_start_pmc(int cpu, int ri, struct pmc *pm)
301 {
302 	uint32_t config;
303 
304 	config = pm->pm_md.pm_arm64.pm_arm64_evsel;
305 
306 	/*
307 	 * Configure the event selection.
308 	 */
309 	WRITE_SPECIALREG(pmselr_el0, ri);
310 	WRITE_SPECIALREG(pmxevtyper_el0, config);
311 
312 	isb();
313 
314 	/*
315 	 * Enable the PMC.
316 	 */
317 	arm64_interrupt_enable(ri);
318 	arm64_counter_enable(ri);
319 
320 	return (0);
321 }
322 
323 static int
324 arm64_stop_pmc(int cpu, int ri, struct pmc *pm __unused)
325 {
326 	/*
327 	 * Disable the PMCs.
328 	 */
329 	arm64_counter_disable(ri);
330 	arm64_interrupt_disable(ri);
331 
332 	return (0);
333 }
334 
335 static int
336 arm64_release_pmc(int cpu, int ri, struct pmc *pmc)
337 {
338 	struct pmc_hw *phw __diagused;
339 
340 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
341 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
342 	KASSERT(ri >= 0 && ri < arm64_npmcs,
343 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
344 
345 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
346 	KASSERT(phw->phw_pmc == NULL,
347 	    ("[arm64,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
348 
349 	return (0);
350 }
351 
352 static int
353 arm64_intr(struct trapframe *tf)
354 {
355 	int retval, ri;
356 	struct pmc *pm;
357 	int error;
358 	int reg, cpu;
359 
360 	cpu = curcpu;
361 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
362 	    ("[arm64,%d] CPU %d out of range", __LINE__, cpu));
363 
364 	PMCDBG3(MDP,INT,1, "cpu=%d tf=%p um=%d", cpu, (void *)tf,
365 	    TRAPF_USERMODE(tf));
366 
367 	retval = 0;
368 
369 	for (ri = 0; ri < arm64_npmcs; ri++) {
370 		pm = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
371 		if (pm == NULL)
372 			continue;
373 		/* Check if counter is overflowed */
374 		reg = (1 << ri);
375 		if ((READ_SPECIALREG(pmovsclr_el0) & reg) == 0)
376 			continue;
377 		/* Clear Overflow Flag */
378 		WRITE_SPECIALREG(pmovsclr_el0, reg);
379 
380 		isb();
381 
382 		retval = 1; /* Found an interrupting PMC. */
383 
384 		pm->pm_pcpu_state[cpu].pps_overflowcnt += 1;
385 
386 		if (!PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
387 			continue;
388 
389 		if (pm->pm_state != PMC_STATE_RUNNING)
390 			continue;
391 
392 		error = pmc_process_interrupt(PMC_HR, pm, tf);
393 		if (error)
394 			arm64_stop_pmc(cpu, ri, pm);
395 
396 		/* Reload sampling count */
397 		arm64_write_pmc(cpu, ri, pm, pm->pm_sc.pm_reloadcount);
398 	}
399 
400 	return (retval);
401 }
402 
403 static int
404 arm64_describe(int cpu, int ri, struct pmc_info *pi, struct pmc **ppmc)
405 {
406 	struct pmc_hw *phw;
407 
408 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
409 	    ("[arm64,%d], illegal CPU %d", __LINE__, cpu));
410 	KASSERT(ri >= 0 && ri < arm64_npmcs,
411 	    ("[arm64,%d] row-index %d out of range", __LINE__, ri));
412 
413 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
414 
415 	snprintf(pi->pm_name, sizeof(pi->pm_name), "ARMV8-%d", ri);
416 	pi->pm_class = PMC_CLASS_ARMV8;
417 
418 	if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
419 		pi->pm_enabled = TRUE;
420 		*ppmc = phw->phw_pmc;
421 	} else {
422 		pi->pm_enabled = FALSE;
423 		*ppmc = NULL;
424 	}
425 
426 	return (0);
427 }
428 
429 static int
430 arm64_get_config(int cpu, int ri, struct pmc **ppm)
431 {
432 
433 	*ppm = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
434 
435 	return (0);
436 }
437 
438 static int
439 arm64_pcpu_init(struct pmc_mdep *md, int cpu)
440 {
441 	struct arm64_cpu *pac;
442 	struct pmc_hw  *phw;
443 	struct pmc_cpu *pc;
444 	uint64_t pmcr;
445 	int first_ri;
446 	int i;
447 
448 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
449 	    ("[arm64,%d] wrong cpu number %d", __LINE__, cpu));
450 	PMCDBG0(MDP, INI, 1, "arm64-pcpu-init");
451 
452 	arm64_pcpu[cpu] = pac = malloc(sizeof(struct arm64_cpu), M_PMC,
453 	    M_WAITOK | M_ZERO);
454 
455 	pac->pc_arm64pmcs = malloc(sizeof(struct pmc_hw) * arm64_npmcs,
456 	    M_PMC, M_WAITOK | M_ZERO);
457 	pc = pmc_pcpu[cpu];
458 	first_ri = md->pmd_classdep[PMC_MDEP_CLASS_INDEX_ARMV8].pcd_ri;
459 	KASSERT(pc != NULL, ("[arm64,%d] NULL per-cpu pointer", __LINE__));
460 
461 	for (i = 0, phw = pac->pc_arm64pmcs; i < arm64_npmcs; i++, phw++) {
462 		phw->phw_state    = PMC_PHW_FLAG_IS_ENABLED |
463 		    PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(i);
464 		phw->phw_pmc      = NULL;
465 		pc->pc_hwpmcs[i + first_ri] = phw;
466 	}
467 
468 	/*
469 	 * Disable all counters and overflow interrupts. Upon reset they are in
470 	 * an undefined state.
471 	 *
472 	 * Don't issue an isb here, just wait for the one in arm64_pmcr_write()
473 	 * to make the writes visible.
474 	 */
475 	WRITE_SPECIALREG(pmcntenclr_el0, 0xffffffff);
476 	WRITE_SPECIALREG(pmintenclr_el1, 0xffffffff);
477 
478 	/* Enable unit */
479 	pmcr = arm64_pmcr_read();
480 	pmcr |= PMCR_E;
481 	arm64_pmcr_write(pmcr);
482 
483 	return (0);
484 }
485 
486 static int
487 arm64_pcpu_fini(struct pmc_mdep *md, int cpu)
488 {
489 	uint32_t pmcr;
490 
491 	PMCDBG0(MDP, INI, 1, "arm64-pcpu-fini");
492 
493 	pmcr = arm64_pmcr_read();
494 	pmcr &= ~PMCR_E;
495 	arm64_pmcr_write(pmcr);
496 
497 	free(arm64_pcpu[cpu]->pc_arm64pmcs, M_PMC);
498 	free(arm64_pcpu[cpu], M_PMC);
499 	arm64_pcpu[cpu] = NULL;
500 
501 	return (0);
502 }
503 
504 struct pmc_mdep *
505 pmc_arm64_initialize(void)
506 {
507 	struct pmc_mdep *pmc_mdep;
508 	struct pmc_classdep *pcd;
509 	int classes, idcode, impcode;
510 	int reg;
511 	uint64_t midr;
512 
513 	reg = arm64_pmcr_read();
514 	arm64_npmcs = (reg & PMCR_N_MASK) >> PMCR_N_SHIFT;
515 	impcode = (reg & PMCR_IMP_MASK) >> PMCR_IMP_SHIFT;
516 	idcode = (reg & PMCR_IDCODE_MASK) >> PMCR_IDCODE_SHIFT;
517 
518 	PMCDBG1(MDP, INI, 1, "arm64-init npmcs=%d", arm64_npmcs);
519 
520 	/*
521 	 * Write the CPU model to kern.hwpmc.cpuid.
522 	 *
523 	 * We zero the variant and revision fields.
524 	 *
525 	 * TODO: how to handle differences between cores due to big.LITTLE?
526 	 * For now, just use MIDR from CPU 0.
527 	 */
528 	midr = (uint64_t)(pcpu_find(0)->pc_midr);
529 	midr &= ~(CPU_VAR_MASK | CPU_REV_MASK);
530 	snprintf(pmc_cpuid, sizeof(pmc_cpuid), "0x%016lx", midr);
531 
532 	/*
533 	 * Allocate space for pointers to PMC HW descriptors and for
534 	 * the MDEP structure used by MI code.
535 	 */
536 	arm64_pcpu = malloc(sizeof(struct arm64_cpu *) * pmc_cpu_max(),
537 		M_PMC, M_WAITOK | M_ZERO);
538 
539 	/* One AArch64 CPU class */
540 	classes = 1;
541 
542 #ifdef DEV_ACPI
543 	/* Query presence of optional classes and set max class. */
544 	if (pmc_cmn600_nclasses() > 0)
545 		classes = MAX(classes, PMC_MDEP_CLASS_INDEX_CMN600);
546 	if (pmc_dmc620_nclasses() > 0)
547 		classes = MAX(classes, PMC_MDEP_CLASS_INDEX_DMC620_C);
548 #endif
549 
550 	pmc_mdep = pmc_mdep_alloc(classes);
551 
552 	switch(impcode) {
553 	case PMCR_IMP_ARM:
554 		switch (idcode) {
555 		case PMCR_IDCODE_CORTEX_A76:
556 		case PMCR_IDCODE_NEOVERSE_N1:
557 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A76;
558 			break;
559 		case PMCR_IDCODE_CORTEX_A57:
560 		case PMCR_IDCODE_CORTEX_A72:
561 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A57;
562 			break;
563 		default:
564 		case PMCR_IDCODE_CORTEX_A53:
565 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A53;
566 			break;
567 		}
568 		break;
569 	default:
570 		pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A53;
571 		break;
572 	}
573 
574 	pcd = &pmc_mdep->pmd_classdep[PMC_MDEP_CLASS_INDEX_ARMV8];
575 	pcd->pcd_caps  = ARMV8_PMC_CAPS;
576 	pcd->pcd_class = PMC_CLASS_ARMV8;
577 	pcd->pcd_num   = arm64_npmcs;
578 	pcd->pcd_ri    = pmc_mdep->pmd_npmc;
579 	pcd->pcd_width = 32;
580 
581 	pcd->pcd_allocate_pmc   = arm64_allocate_pmc;
582 	pcd->pcd_config_pmc     = arm64_config_pmc;
583 	pcd->pcd_pcpu_fini      = arm64_pcpu_fini;
584 	pcd->pcd_pcpu_init      = arm64_pcpu_init;
585 	pcd->pcd_describe       = arm64_describe;
586 	pcd->pcd_get_config     = arm64_get_config;
587 	pcd->pcd_read_pmc       = arm64_read_pmc;
588 	pcd->pcd_release_pmc    = arm64_release_pmc;
589 	pcd->pcd_start_pmc      = arm64_start_pmc;
590 	pcd->pcd_stop_pmc       = arm64_stop_pmc;
591 	pcd->pcd_write_pmc      = arm64_write_pmc;
592 
593 	pmc_mdep->pmd_intr = arm64_intr;
594 	pmc_mdep->pmd_npmc += arm64_npmcs;
595 
596 #ifdef DEV_ACPI
597 	if (pmc_cmn600_nclasses() > 0)
598 		pmc_cmn600_initialize(pmc_mdep);
599 	if (pmc_dmc620_nclasses() > 0) {
600 		pmc_dmc620_initialize_cd2(pmc_mdep);
601 		pmc_dmc620_initialize_c(pmc_mdep);
602 	}
603 #endif
604 
605 	return (pmc_mdep);
606 }
607 
608 void
609 pmc_arm64_finalize(struct pmc_mdep *md)
610 {
611 	PMCDBG0(MDP, INI, 1, "arm64-finalize");
612 
613 	for (int i = 0; i < pmc_cpu_max(); i++)
614 		KASSERT(arm64_pcpu[i] == NULL,
615 		    ("[arm64,%d] non-null pcpu cpu %d", __LINE__, i));
616 
617 	free(arm64_pcpu, M_PMC);
618 }
619