1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * ARMv8 PMUv3 Performance Events handling code.
4 *
5 * Copyright (C) 2012 ARM Limited
6 * Author: Will Deacon <will.deacon@arm.com>
7 *
8 * This code is based heavily on the ARMv7 perf event code.
9 */
10
11#include <asm/irq_regs.h>
12#include <asm/perf_event.h>
13#include <asm/virt.h>
14
15#include <clocksource/arm_arch_timer.h>
16
17#include <linux/acpi.h>
18#include <linux/bitfield.h>
19#include <linux/clocksource.h>
20#include <linux/of.h>
21#include <linux/perf/arm_pmu.h>
22#include <linux/perf/arm_pmuv3.h>
23#include <linux/platform_device.h>
24#include <linux/sched_clock.h>
25#include <linux/smp.h>
26#include <linux/nmi.h>
27
28#include <asm/arm_pmuv3.h>
29
30/* ARMv8 Cortex-A53 specific event types. */
31#define ARMV8_A53_PERFCTR_PREF_LINEFILL 0xC2
32
33/* ARMv8 Cavium ThunderX specific event types. */
34#define ARMV8_THUNDER_PERFCTR_L1D_CACHE_MISS_ST 0xE9
35#define ARMV8_THUNDER_PERFCTR_L1D_CACHE_PREF_ACCESS 0xEA
36#define ARMV8_THUNDER_PERFCTR_L1D_CACHE_PREF_MISS 0xEB
37#define ARMV8_THUNDER_PERFCTR_L1I_CACHE_PREF_ACCESS 0xEC
38#define ARMV8_THUNDER_PERFCTR_L1I_CACHE_PREF_MISS 0xED
39
40/*
41 * ARMv8 Architectural defined events, not all of these may
42 * be supported on any given implementation. Unsupported events will
43 * be disabled at run-time based on the PMCEID registers.
44 */
45static const unsigned armv8_pmuv3_perf_map[PERF_COUNT_HW_MAX] = {
46 PERF_MAP_ALL_UNSUPPORTED,
47 [PERF_COUNT_HW_CPU_CYCLES] = ARMV8_PMUV3_PERFCTR_CPU_CYCLES,
48 [PERF_COUNT_HW_INSTRUCTIONS] = ARMV8_PMUV3_PERFCTR_INST_RETIRED,
49 [PERF_COUNT_HW_CACHE_REFERENCES] = ARMV8_PMUV3_PERFCTR_L1D_CACHE,
50 [PERF_COUNT_HW_CACHE_MISSES] = ARMV8_PMUV3_PERFCTR_L1D_CACHE_REFILL,
51 [PERF_COUNT_HW_BRANCH_MISSES] = ARMV8_PMUV3_PERFCTR_BR_MIS_PRED,
52 [PERF_COUNT_HW_BUS_CYCLES] = ARMV8_PMUV3_PERFCTR_BUS_CYCLES,
53 [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = ARMV8_PMUV3_PERFCTR_STALL_FRONTEND,
54 [PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = ARMV8_PMUV3_PERFCTR_STALL_BACKEND,
55};
56
57static const unsigned armv8_pmuv3_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
58 [PERF_COUNT_HW_CACHE_OP_MAX]
59 [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
60 PERF_CACHE_MAP_ALL_UNSUPPORTED,
61
62 [C(L1D)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_L1D_CACHE,
63 [C(L1D)][C(OP_READ)][C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_L1D_CACHE_REFILL,
64
65 [C(L1I)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_L1I_CACHE,
66 [C(L1I)][C(OP_READ)][C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_L1I_CACHE_REFILL,
67
68 [C(DTLB)][C(OP_READ)][C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_L1D_TLB_REFILL,
69 [C(DTLB)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_L1D_TLB,
70
71 [C(ITLB)][C(OP_READ)][C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_L1I_TLB_REFILL,
72 [C(ITLB)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_L1I_TLB,
73
74 [C(LL)][C(OP_READ)][C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_LL_CACHE_MISS_RD,
75 [C(LL)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_LL_CACHE_RD,
76
77 [C(BPU)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_BR_PRED,
78 [C(BPU)][C(OP_READ)][C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_BR_MIS_PRED,
79};
80
81static const unsigned armv8_a53_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
82 [PERF_COUNT_HW_CACHE_OP_MAX]
83 [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
84 PERF_CACHE_MAP_ALL_UNSUPPORTED,
85
86 [C(L1D)][C(OP_PREFETCH)][C(RESULT_MISS)] = ARMV8_A53_PERFCTR_PREF_LINEFILL,
87
88 [C(NODE)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_BUS_ACCESS_RD,
89 [C(NODE)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_BUS_ACCESS_WR,
90};
91
92static const unsigned armv8_a57_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
93 [PERF_COUNT_HW_CACHE_OP_MAX]
94 [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
95 PERF_CACHE_MAP_ALL_UNSUPPORTED,
96
97 [C(L1D)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_CACHE_RD,
98 [C(L1D)][C(OP_READ)][C(RESULT_MISS)] = ARMV8_IMPDEF_PERFCTR_L1D_CACHE_REFILL_RD,
99 [C(L1D)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_CACHE_WR,
100 [C(L1D)][C(OP_WRITE)][C(RESULT_MISS)] = ARMV8_IMPDEF_PERFCTR_L1D_CACHE_REFILL_WR,
101
102 [C(DTLB)][C(OP_READ)][C(RESULT_MISS)] = ARMV8_IMPDEF_PERFCTR_L1D_TLB_REFILL_RD,
103 [C(DTLB)][C(OP_WRITE)][C(RESULT_MISS)] = ARMV8_IMPDEF_PERFCTR_L1D_TLB_REFILL_WR,
104
105 [C(NODE)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_BUS_ACCESS_RD,
106 [C(NODE)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_BUS_ACCESS_WR,
107};
108
109static const unsigned armv8_a73_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
110 [PERF_COUNT_HW_CACHE_OP_MAX]
111 [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
112 PERF_CACHE_MAP_ALL_UNSUPPORTED,
113
114 [C(L1D)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_CACHE_RD,
115 [C(L1D)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_CACHE_WR,
116};
117
118static const unsigned armv8_thunder_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
119 [PERF_COUNT_HW_CACHE_OP_MAX]
120 [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
121 PERF_CACHE_MAP_ALL_UNSUPPORTED,
122
123 [C(L1D)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_CACHE_RD,
124 [C(L1D)][C(OP_READ)][C(RESULT_MISS)] = ARMV8_IMPDEF_PERFCTR_L1D_CACHE_REFILL_RD,
125 [C(L1D)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_CACHE_WR,
126 [C(L1D)][C(OP_WRITE)][C(RESULT_MISS)] = ARMV8_THUNDER_PERFCTR_L1D_CACHE_MISS_ST,
127 [C(L1D)][C(OP_PREFETCH)][C(RESULT_ACCESS)] = ARMV8_THUNDER_PERFCTR_L1D_CACHE_PREF_ACCESS,
128 [C(L1D)][C(OP_PREFETCH)][C(RESULT_MISS)] = ARMV8_THUNDER_PERFCTR_L1D_CACHE_PREF_MISS,
129
130 [C(L1I)][C(OP_PREFETCH)][C(RESULT_ACCESS)] = ARMV8_THUNDER_PERFCTR_L1I_CACHE_PREF_ACCESS,
131 [C(L1I)][C(OP_PREFETCH)][C(RESULT_MISS)] = ARMV8_THUNDER_PERFCTR_L1I_CACHE_PREF_MISS,
132
133 [C(DTLB)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_TLB_RD,
134 [C(DTLB)][C(OP_READ)][C(RESULT_MISS)] = ARMV8_IMPDEF_PERFCTR_L1D_TLB_REFILL_RD,
135 [C(DTLB)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_TLB_WR,
136 [C(DTLB)][C(OP_WRITE)][C(RESULT_MISS)] = ARMV8_IMPDEF_PERFCTR_L1D_TLB_REFILL_WR,
137};
138
139static const unsigned armv8_vulcan_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
140 [PERF_COUNT_HW_CACHE_OP_MAX]
141 [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
142 PERF_CACHE_MAP_ALL_UNSUPPORTED,
143
144 [C(L1D)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_CACHE_RD,
145 [C(L1D)][C(OP_READ)][C(RESULT_MISS)] = ARMV8_IMPDEF_PERFCTR_L1D_CACHE_REFILL_RD,
146 [C(L1D)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_CACHE_WR,
147 [C(L1D)][C(OP_WRITE)][C(RESULT_MISS)] = ARMV8_IMPDEF_PERFCTR_L1D_CACHE_REFILL_WR,
148
149 [C(DTLB)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_TLB_RD,
150 [C(DTLB)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_TLB_WR,
151 [C(DTLB)][C(OP_READ)][C(RESULT_MISS)] = ARMV8_IMPDEF_PERFCTR_L1D_TLB_REFILL_RD,
152 [C(DTLB)][C(OP_WRITE)][C(RESULT_MISS)] = ARMV8_IMPDEF_PERFCTR_L1D_TLB_REFILL_WR,
153
154 [C(NODE)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_BUS_ACCESS_RD,
155 [C(NODE)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_BUS_ACCESS_WR,
156};
157
158static ssize_t
159armv8pmu_events_sysfs_show(struct device *dev,
160 struct device_attribute *attr, char *page)
161{
162 struct perf_pmu_events_attr *pmu_attr;
163
164 pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
165
166 return sprintf(buf: page, fmt: "event=0x%04llx\n", pmu_attr->id);
167}
168
169#define ARMV8_EVENT_ATTR(name, config) \
170 PMU_EVENT_ATTR_ID(name, armv8pmu_events_sysfs_show, config)
171
172static struct attribute *armv8_pmuv3_event_attrs[] = {
173 /*
174 * Don't expose the sw_incr event in /sys. It's not usable as writes to
175 * PMSWINC_EL0 will trap as PMUSERENR.{SW,EN}=={0,0} and event rotation
176 * means we don't have a fixed event<->counter relationship regardless.
177 */
178 ARMV8_EVENT_ATTR(l1i_cache_refill, ARMV8_PMUV3_PERFCTR_L1I_CACHE_REFILL),
179 ARMV8_EVENT_ATTR(l1i_tlb_refill, ARMV8_PMUV3_PERFCTR_L1I_TLB_REFILL),
180 ARMV8_EVENT_ATTR(l1d_cache_refill, ARMV8_PMUV3_PERFCTR_L1D_CACHE_REFILL),
181 ARMV8_EVENT_ATTR(l1d_cache, ARMV8_PMUV3_PERFCTR_L1D_CACHE),
182 ARMV8_EVENT_ATTR(l1d_tlb_refill, ARMV8_PMUV3_PERFCTR_L1D_TLB_REFILL),
183 ARMV8_EVENT_ATTR(ld_retired, ARMV8_PMUV3_PERFCTR_LD_RETIRED),
184 ARMV8_EVENT_ATTR(st_retired, ARMV8_PMUV3_PERFCTR_ST_RETIRED),
185 ARMV8_EVENT_ATTR(inst_retired, ARMV8_PMUV3_PERFCTR_INST_RETIRED),
186 ARMV8_EVENT_ATTR(exc_taken, ARMV8_PMUV3_PERFCTR_EXC_TAKEN),
187 ARMV8_EVENT_ATTR(exc_return, ARMV8_PMUV3_PERFCTR_EXC_RETURN),
188 ARMV8_EVENT_ATTR(cid_write_retired, ARMV8_PMUV3_PERFCTR_CID_WRITE_RETIRED),
189 ARMV8_EVENT_ATTR(pc_write_retired, ARMV8_PMUV3_PERFCTR_PC_WRITE_RETIRED),
190 ARMV8_EVENT_ATTR(br_immed_retired, ARMV8_PMUV3_PERFCTR_BR_IMMED_RETIRED),
191 ARMV8_EVENT_ATTR(br_return_retired, ARMV8_PMUV3_PERFCTR_BR_RETURN_RETIRED),
192 ARMV8_EVENT_ATTR(unaligned_ldst_retired, ARMV8_PMUV3_PERFCTR_UNALIGNED_LDST_RETIRED),
193 ARMV8_EVENT_ATTR(br_mis_pred, ARMV8_PMUV3_PERFCTR_BR_MIS_PRED),
194 ARMV8_EVENT_ATTR(cpu_cycles, ARMV8_PMUV3_PERFCTR_CPU_CYCLES),
195 ARMV8_EVENT_ATTR(br_pred, ARMV8_PMUV3_PERFCTR_BR_PRED),
196 ARMV8_EVENT_ATTR(mem_access, ARMV8_PMUV3_PERFCTR_MEM_ACCESS),
197 ARMV8_EVENT_ATTR(l1i_cache, ARMV8_PMUV3_PERFCTR_L1I_CACHE),
198 ARMV8_EVENT_ATTR(l1d_cache_wb, ARMV8_PMUV3_PERFCTR_L1D_CACHE_WB),
199 ARMV8_EVENT_ATTR(l2d_cache, ARMV8_PMUV3_PERFCTR_L2D_CACHE),
200 ARMV8_EVENT_ATTR(l2d_cache_refill, ARMV8_PMUV3_PERFCTR_L2D_CACHE_REFILL),
201 ARMV8_EVENT_ATTR(l2d_cache_wb, ARMV8_PMUV3_PERFCTR_L2D_CACHE_WB),
202 ARMV8_EVENT_ATTR(bus_access, ARMV8_PMUV3_PERFCTR_BUS_ACCESS),
203 ARMV8_EVENT_ATTR(memory_error, ARMV8_PMUV3_PERFCTR_MEMORY_ERROR),
204 ARMV8_EVENT_ATTR(inst_spec, ARMV8_PMUV3_PERFCTR_INST_SPEC),
205 ARMV8_EVENT_ATTR(ttbr_write_retired, ARMV8_PMUV3_PERFCTR_TTBR_WRITE_RETIRED),
206 ARMV8_EVENT_ATTR(bus_cycles, ARMV8_PMUV3_PERFCTR_BUS_CYCLES),
207 /* Don't expose the chain event in /sys, since it's useless in isolation */
208 ARMV8_EVENT_ATTR(l1d_cache_allocate, ARMV8_PMUV3_PERFCTR_L1D_CACHE_ALLOCATE),
209 ARMV8_EVENT_ATTR(l2d_cache_allocate, ARMV8_PMUV3_PERFCTR_L2D_CACHE_ALLOCATE),
210 ARMV8_EVENT_ATTR(br_retired, ARMV8_PMUV3_PERFCTR_BR_RETIRED),
211 ARMV8_EVENT_ATTR(br_mis_pred_retired, ARMV8_PMUV3_PERFCTR_BR_MIS_PRED_RETIRED),
212 ARMV8_EVENT_ATTR(stall_frontend, ARMV8_PMUV3_PERFCTR_STALL_FRONTEND),
213 ARMV8_EVENT_ATTR(stall_backend, ARMV8_PMUV3_PERFCTR_STALL_BACKEND),
214 ARMV8_EVENT_ATTR(l1d_tlb, ARMV8_PMUV3_PERFCTR_L1D_TLB),
215 ARMV8_EVENT_ATTR(l1i_tlb, ARMV8_PMUV3_PERFCTR_L1I_TLB),
216 ARMV8_EVENT_ATTR(l2i_cache, ARMV8_PMUV3_PERFCTR_L2I_CACHE),
217 ARMV8_EVENT_ATTR(l2i_cache_refill, ARMV8_PMUV3_PERFCTR_L2I_CACHE_REFILL),
218 ARMV8_EVENT_ATTR(l3d_cache_allocate, ARMV8_PMUV3_PERFCTR_L3D_CACHE_ALLOCATE),
219 ARMV8_EVENT_ATTR(l3d_cache_refill, ARMV8_PMUV3_PERFCTR_L3D_CACHE_REFILL),
220 ARMV8_EVENT_ATTR(l3d_cache, ARMV8_PMUV3_PERFCTR_L3D_CACHE),
221 ARMV8_EVENT_ATTR(l3d_cache_wb, ARMV8_PMUV3_PERFCTR_L3D_CACHE_WB),
222 ARMV8_EVENT_ATTR(l2d_tlb_refill, ARMV8_PMUV3_PERFCTR_L2D_TLB_REFILL),
223 ARMV8_EVENT_ATTR(l2i_tlb_refill, ARMV8_PMUV3_PERFCTR_L2I_TLB_REFILL),
224 ARMV8_EVENT_ATTR(l2d_tlb, ARMV8_PMUV3_PERFCTR_L2D_TLB),
225 ARMV8_EVENT_ATTR(l2i_tlb, ARMV8_PMUV3_PERFCTR_L2I_TLB),
226 ARMV8_EVENT_ATTR(remote_access, ARMV8_PMUV3_PERFCTR_REMOTE_ACCESS),
227 ARMV8_EVENT_ATTR(ll_cache, ARMV8_PMUV3_PERFCTR_LL_CACHE),
228 ARMV8_EVENT_ATTR(ll_cache_miss, ARMV8_PMUV3_PERFCTR_LL_CACHE_MISS),
229 ARMV8_EVENT_ATTR(dtlb_walk, ARMV8_PMUV3_PERFCTR_DTLB_WALK),
230 ARMV8_EVENT_ATTR(itlb_walk, ARMV8_PMUV3_PERFCTR_ITLB_WALK),
231 ARMV8_EVENT_ATTR(ll_cache_rd, ARMV8_PMUV3_PERFCTR_LL_CACHE_RD),
232 ARMV8_EVENT_ATTR(ll_cache_miss_rd, ARMV8_PMUV3_PERFCTR_LL_CACHE_MISS_RD),
233 ARMV8_EVENT_ATTR(remote_access_rd, ARMV8_PMUV3_PERFCTR_REMOTE_ACCESS_RD),
234 ARMV8_EVENT_ATTR(l1d_cache_lmiss_rd, ARMV8_PMUV3_PERFCTR_L1D_CACHE_LMISS_RD),
235 ARMV8_EVENT_ATTR(op_retired, ARMV8_PMUV3_PERFCTR_OP_RETIRED),
236 ARMV8_EVENT_ATTR(op_spec, ARMV8_PMUV3_PERFCTR_OP_SPEC),
237 ARMV8_EVENT_ATTR(stall, ARMV8_PMUV3_PERFCTR_STALL),
238 ARMV8_EVENT_ATTR(stall_slot_backend, ARMV8_PMUV3_PERFCTR_STALL_SLOT_BACKEND),
239 ARMV8_EVENT_ATTR(stall_slot_frontend, ARMV8_PMUV3_PERFCTR_STALL_SLOT_FRONTEND),
240 ARMV8_EVENT_ATTR(stall_slot, ARMV8_PMUV3_PERFCTR_STALL_SLOT),
241 ARMV8_EVENT_ATTR(sample_pop, ARMV8_SPE_PERFCTR_SAMPLE_POP),
242 ARMV8_EVENT_ATTR(sample_feed, ARMV8_SPE_PERFCTR_SAMPLE_FEED),
243 ARMV8_EVENT_ATTR(sample_filtrate, ARMV8_SPE_PERFCTR_SAMPLE_FILTRATE),
244 ARMV8_EVENT_ATTR(sample_collision, ARMV8_SPE_PERFCTR_SAMPLE_COLLISION),
245 ARMV8_EVENT_ATTR(cnt_cycles, ARMV8_AMU_PERFCTR_CNT_CYCLES),
246 ARMV8_EVENT_ATTR(stall_backend_mem, ARMV8_AMU_PERFCTR_STALL_BACKEND_MEM),
247 ARMV8_EVENT_ATTR(l1i_cache_lmiss, ARMV8_PMUV3_PERFCTR_L1I_CACHE_LMISS),
248 ARMV8_EVENT_ATTR(l2d_cache_lmiss_rd, ARMV8_PMUV3_PERFCTR_L2D_CACHE_LMISS_RD),
249 ARMV8_EVENT_ATTR(l2i_cache_lmiss, ARMV8_PMUV3_PERFCTR_L2I_CACHE_LMISS),
250 ARMV8_EVENT_ATTR(l3d_cache_lmiss_rd, ARMV8_PMUV3_PERFCTR_L3D_CACHE_LMISS_RD),
251 ARMV8_EVENT_ATTR(trb_wrap, ARMV8_PMUV3_PERFCTR_TRB_WRAP),
252 ARMV8_EVENT_ATTR(trb_trig, ARMV8_PMUV3_PERFCTR_TRB_TRIG),
253 ARMV8_EVENT_ATTR(trcextout0, ARMV8_PMUV3_PERFCTR_TRCEXTOUT0),
254 ARMV8_EVENT_ATTR(trcextout1, ARMV8_PMUV3_PERFCTR_TRCEXTOUT1),
255 ARMV8_EVENT_ATTR(trcextout2, ARMV8_PMUV3_PERFCTR_TRCEXTOUT2),
256 ARMV8_EVENT_ATTR(trcextout3, ARMV8_PMUV3_PERFCTR_TRCEXTOUT3),
257 ARMV8_EVENT_ATTR(cti_trigout4, ARMV8_PMUV3_PERFCTR_CTI_TRIGOUT4),
258 ARMV8_EVENT_ATTR(cti_trigout5, ARMV8_PMUV3_PERFCTR_CTI_TRIGOUT5),
259 ARMV8_EVENT_ATTR(cti_trigout6, ARMV8_PMUV3_PERFCTR_CTI_TRIGOUT6),
260 ARMV8_EVENT_ATTR(cti_trigout7, ARMV8_PMUV3_PERFCTR_CTI_TRIGOUT7),
261 ARMV8_EVENT_ATTR(ldst_align_lat, ARMV8_PMUV3_PERFCTR_LDST_ALIGN_LAT),
262 ARMV8_EVENT_ATTR(ld_align_lat, ARMV8_PMUV3_PERFCTR_LD_ALIGN_LAT),
263 ARMV8_EVENT_ATTR(st_align_lat, ARMV8_PMUV3_PERFCTR_ST_ALIGN_LAT),
264 ARMV8_EVENT_ATTR(mem_access_checked, ARMV8_MTE_PERFCTR_MEM_ACCESS_CHECKED),
265 ARMV8_EVENT_ATTR(mem_access_checked_rd, ARMV8_MTE_PERFCTR_MEM_ACCESS_CHECKED_RD),
266 ARMV8_EVENT_ATTR(mem_access_checked_wr, ARMV8_MTE_PERFCTR_MEM_ACCESS_CHECKED_WR),
267 NULL,
268};
269
270static umode_t
271armv8pmu_event_attr_is_visible(struct kobject *kobj,
272 struct attribute *attr, int unused)
273{
274 struct device *dev = kobj_to_dev(kobj);
275 struct pmu *pmu = dev_get_drvdata(dev);
276 struct arm_pmu *cpu_pmu = container_of(pmu, struct arm_pmu, pmu);
277 struct perf_pmu_events_attr *pmu_attr;
278
279 pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr.attr);
280
281 if (pmu_attr->id < ARMV8_PMUV3_MAX_COMMON_EVENTS &&
282 test_bit(pmu_attr->id, cpu_pmu->pmceid_bitmap))
283 return attr->mode;
284
285 if (pmu_attr->id >= ARMV8_PMUV3_EXT_COMMON_EVENT_BASE) {
286 u64 id = pmu_attr->id - ARMV8_PMUV3_EXT_COMMON_EVENT_BASE;
287
288 if (id < ARMV8_PMUV3_MAX_COMMON_EVENTS &&
289 test_bit(id, cpu_pmu->pmceid_ext_bitmap))
290 return attr->mode;
291 }
292
293 return 0;
294}
295
296static const struct attribute_group armv8_pmuv3_events_attr_group = {
297 .name = "events",
298 .attrs = armv8_pmuv3_event_attrs,
299 .is_visible = armv8pmu_event_attr_is_visible,
300};
301
302/* User ABI */
303#define ATTR_CFG_FLD_event_CFG config
304#define ATTR_CFG_FLD_event_LO 0
305#define ATTR_CFG_FLD_event_HI 15
306#define ATTR_CFG_FLD_long_CFG config1
307#define ATTR_CFG_FLD_long_LO 0
308#define ATTR_CFG_FLD_long_HI 0
309#define ATTR_CFG_FLD_rdpmc_CFG config1
310#define ATTR_CFG_FLD_rdpmc_LO 1
311#define ATTR_CFG_FLD_rdpmc_HI 1
312#define ATTR_CFG_FLD_threshold_count_CFG config1 /* PMEVTYPER.TC[0] */
313#define ATTR_CFG_FLD_threshold_count_LO 2
314#define ATTR_CFG_FLD_threshold_count_HI 2
315#define ATTR_CFG_FLD_threshold_compare_CFG config1 /* PMEVTYPER.TC[2:1] */
316#define ATTR_CFG_FLD_threshold_compare_LO 3
317#define ATTR_CFG_FLD_threshold_compare_HI 4
318#define ATTR_CFG_FLD_threshold_CFG config1 /* PMEVTYPER.TH */
319#define ATTR_CFG_FLD_threshold_LO 5
320#define ATTR_CFG_FLD_threshold_HI 16
321
322GEN_PMU_FORMAT_ATTR(event);
323GEN_PMU_FORMAT_ATTR(long);
324GEN_PMU_FORMAT_ATTR(rdpmc);
325GEN_PMU_FORMAT_ATTR(threshold_count);
326GEN_PMU_FORMAT_ATTR(threshold_compare);
327GEN_PMU_FORMAT_ATTR(threshold);
328
329static int sysctl_perf_user_access __read_mostly;
330
331static bool armv8pmu_event_is_64bit(struct perf_event *event)
332{
333 return ATTR_CFG_GET_FLD(&event->attr, long);
334}
335
336static bool armv8pmu_event_want_user_access(struct perf_event *event)
337{
338 return ATTR_CFG_GET_FLD(&event->attr, rdpmc);
339}
340
341static u8 armv8pmu_event_threshold_control(struct perf_event_attr *attr)
342{
343 u8 th_compare = ATTR_CFG_GET_FLD(attr, threshold_compare);
344 u8 th_count = ATTR_CFG_GET_FLD(attr, threshold_count);
345
346 /*
347 * The count bit is always the bottom bit of the full control field, and
348 * the comparison is the upper two bits, but it's not explicitly
349 * labelled in the Arm ARM. For the Perf interface we split it into two
350 * fields, so reconstruct it here.
351 */
352 return (th_compare << 1) | th_count;
353}
354
355static struct attribute *armv8_pmuv3_format_attrs[] = {
356 &format_attr_event.attr,
357 &format_attr_long.attr,
358 &format_attr_rdpmc.attr,
359 &format_attr_threshold.attr,
360 &format_attr_threshold_compare.attr,
361 &format_attr_threshold_count.attr,
362 NULL,
363};
364
365static const struct attribute_group armv8_pmuv3_format_attr_group = {
366 .name = "format",
367 .attrs = armv8_pmuv3_format_attrs,
368};
369
370static ssize_t slots_show(struct device *dev, struct device_attribute *attr,
371 char *page)
372{
373 struct pmu *pmu = dev_get_drvdata(dev);
374 struct arm_pmu *cpu_pmu = container_of(pmu, struct arm_pmu, pmu);
375 u32 slots = FIELD_GET(ARMV8_PMU_SLOTS, cpu_pmu->reg_pmmir);
376
377 return sysfs_emit(buf: page, fmt: "0x%08x\n", slots);
378}
379
380static DEVICE_ATTR_RO(slots);
381
382static ssize_t bus_slots_show(struct device *dev, struct device_attribute *attr,
383 char *page)
384{
385 struct pmu *pmu = dev_get_drvdata(dev);
386 struct arm_pmu *cpu_pmu = container_of(pmu, struct arm_pmu, pmu);
387 u32 bus_slots = FIELD_GET(ARMV8_PMU_BUS_SLOTS, cpu_pmu->reg_pmmir);
388
389 return sysfs_emit(buf: page, fmt: "0x%08x\n", bus_slots);
390}
391
392static DEVICE_ATTR_RO(bus_slots);
393
394static ssize_t bus_width_show(struct device *dev, struct device_attribute *attr,
395 char *page)
396{
397 struct pmu *pmu = dev_get_drvdata(dev);
398 struct arm_pmu *cpu_pmu = container_of(pmu, struct arm_pmu, pmu);
399 u32 bus_width = FIELD_GET(ARMV8_PMU_BUS_WIDTH, cpu_pmu->reg_pmmir);
400 u32 val = 0;
401
402 /* Encoded as Log2(number of bytes), plus one */
403 if (bus_width > 2 && bus_width < 13)
404 val = 1 << (bus_width - 1);
405
406 return sysfs_emit(buf: page, fmt: "0x%08x\n", val);
407}
408
409static DEVICE_ATTR_RO(bus_width);
410
411static u32 threshold_max(struct arm_pmu *cpu_pmu)
412{
413 /*
414 * PMMIR.THWIDTH is readable and non-zero on aarch32, but it would be
415 * impossible to write the threshold in the upper 32 bits of PMEVTYPER.
416 */
417 if (IS_ENABLED(CONFIG_ARM))
418 return 0;
419
420 /*
421 * The largest value that can be written to PMEVTYPER<n>_EL0.TH is
422 * (2 ^ PMMIR.THWIDTH) - 1.
423 */
424 return (1 << FIELD_GET(ARMV8_PMU_THWIDTH, cpu_pmu->reg_pmmir)) - 1;
425}
426
427static ssize_t threshold_max_show(struct device *dev,
428 struct device_attribute *attr, char *page)
429{
430 struct pmu *pmu = dev_get_drvdata(dev);
431 struct arm_pmu *cpu_pmu = container_of(pmu, struct arm_pmu, pmu);
432
433 return sysfs_emit(buf: page, fmt: "0x%08x\n", threshold_max(cpu_pmu));
434}
435
436static DEVICE_ATTR_RO(threshold_max);
437
438static struct attribute *armv8_pmuv3_caps_attrs[] = {
439 &dev_attr_slots.attr,
440 &dev_attr_bus_slots.attr,
441 &dev_attr_bus_width.attr,
442 &dev_attr_threshold_max.attr,
443 NULL,
444};
445
446static const struct attribute_group armv8_pmuv3_caps_attr_group = {
447 .name = "caps",
448 .attrs = armv8_pmuv3_caps_attrs,
449};
450
451/*
452 * Perf Events' indices
453 */
454#define ARMV8_IDX_CYCLE_COUNTER 0
455#define ARMV8_IDX_COUNTER0 1
456#define ARMV8_IDX_CYCLE_COUNTER_USER 32
457
458/*
459 * We unconditionally enable ARMv8.5-PMU long event counter support
460 * (64-bit events) where supported. Indicate if this arm_pmu has long
461 * event counter support.
462 *
463 * On AArch32, long counters make no sense (you can't access the top
464 * bits), so we only enable this on AArch64.
465 */
466static bool armv8pmu_has_long_event(struct arm_pmu *cpu_pmu)
467{
468 return (IS_ENABLED(CONFIG_ARM64) && is_pmuv3p5(cpu_pmu->pmuver));
469}
470
471static bool armv8pmu_event_has_user_read(struct perf_event *event)
472{
473 return event->hw.flags & PERF_EVENT_FLAG_USER_READ_CNT;
474}
475
476/*
477 * We must chain two programmable counters for 64 bit events,
478 * except when we have allocated the 64bit cycle counter (for CPU
479 * cycles event) or when user space counter access is enabled.
480 */
481static bool armv8pmu_event_is_chained(struct perf_event *event)
482{
483 int idx = event->hw.idx;
484 struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu);
485
486 return !armv8pmu_event_has_user_read(event) &&
487 armv8pmu_event_is_64bit(event) &&
488 !armv8pmu_has_long_event(cpu_pmu) &&
489 (idx != ARMV8_IDX_CYCLE_COUNTER);
490}
491
492/*
493 * ARMv8 low level PMU access
494 */
495
496/*
497 * Perf Event to low level counters mapping
498 */
499#define ARMV8_IDX_TO_COUNTER(x) \
500 (((x) - ARMV8_IDX_COUNTER0) & ARMV8_PMU_COUNTER_MASK)
501
502static u64 armv8pmu_pmcr_read(void)
503{
504 return read_pmcr();
505}
506
507static void armv8pmu_pmcr_write(u64 val)
508{
509 val &= ARMV8_PMU_PMCR_MASK;
510 isb();
511 write_pmcr(val);
512}
513
514static int armv8pmu_has_overflowed(u32 pmovsr)
515{
516 return pmovsr & ARMV8_PMU_OVERFLOWED_MASK;
517}
518
519static int armv8pmu_counter_has_overflowed(u32 pmnc, int idx)
520{
521 return pmnc & BIT(ARMV8_IDX_TO_COUNTER(idx));
522}
523
524static u64 armv8pmu_read_evcntr(int idx)
525{
526 u32 counter = ARMV8_IDX_TO_COUNTER(idx);
527
528 return read_pmevcntrn(counter);
529}
530
531static u64 armv8pmu_read_hw_counter(struct perf_event *event)
532{
533 int idx = event->hw.idx;
534 u64 val = armv8pmu_read_evcntr(idx);
535
536 if (armv8pmu_event_is_chained(event))
537 val = (val << 32) | armv8pmu_read_evcntr(idx: idx - 1);
538 return val;
539}
540
541/*
542 * The cycle counter is always a 64-bit counter. When ARMV8_PMU_PMCR_LP
543 * is set the event counters also become 64-bit counters. Unless the
544 * user has requested a long counter (attr.config1) then we want to
545 * interrupt upon 32-bit overflow - we achieve this by applying a bias.
546 */
547static bool armv8pmu_event_needs_bias(struct perf_event *event)
548{
549 struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu);
550 struct hw_perf_event *hwc = &event->hw;
551 int idx = hwc->idx;
552
553 if (armv8pmu_event_is_64bit(event))
554 return false;
555
556 if (armv8pmu_has_long_event(cpu_pmu) ||
557 idx == ARMV8_IDX_CYCLE_COUNTER)
558 return true;
559
560 return false;
561}
562
563static u64 armv8pmu_bias_long_counter(struct perf_event *event, u64 value)
564{
565 if (armv8pmu_event_needs_bias(event))
566 value |= GENMASK_ULL(63, 32);
567
568 return value;
569}
570
571static u64 armv8pmu_unbias_long_counter(struct perf_event *event, u64 value)
572{
573 if (armv8pmu_event_needs_bias(event))
574 value &= ~GENMASK_ULL(63, 32);
575
576 return value;
577}
578
579static u64 armv8pmu_read_counter(struct perf_event *event)
580{
581 struct hw_perf_event *hwc = &event->hw;
582 int idx = hwc->idx;
583 u64 value;
584
585 if (idx == ARMV8_IDX_CYCLE_COUNTER)
586 value = read_pmccntr();
587 else
588 value = armv8pmu_read_hw_counter(event);
589
590 return armv8pmu_unbias_long_counter(event, value);
591}
592
593static void armv8pmu_write_evcntr(int idx, u64 value)
594{
595 u32 counter = ARMV8_IDX_TO_COUNTER(idx);
596
597 write_pmevcntrn(counter, value);
598}
599
600static void armv8pmu_write_hw_counter(struct perf_event *event,
601 u64 value)
602{
603 int idx = event->hw.idx;
604
605 if (armv8pmu_event_is_chained(event)) {
606 armv8pmu_write_evcntr(idx, upper_32_bits(value));
607 armv8pmu_write_evcntr(idx: idx - 1, lower_32_bits(value));
608 } else {
609 armv8pmu_write_evcntr(idx, value);
610 }
611}
612
613static void armv8pmu_write_counter(struct perf_event *event, u64 value)
614{
615 struct hw_perf_event *hwc = &event->hw;
616 int idx = hwc->idx;
617
618 value = armv8pmu_bias_long_counter(event, value);
619
620 if (idx == ARMV8_IDX_CYCLE_COUNTER)
621 write_pmccntr(value);
622 else
623 armv8pmu_write_hw_counter(event, value);
624}
625
626static void armv8pmu_write_evtype(int idx, unsigned long val)
627{
628 u32 counter = ARMV8_IDX_TO_COUNTER(idx);
629 unsigned long mask = ARMV8_PMU_EVTYPE_EVENT |
630 ARMV8_PMU_INCLUDE_EL2 |
631 ARMV8_PMU_EXCLUDE_EL0 |
632 ARMV8_PMU_EXCLUDE_EL1;
633
634 if (IS_ENABLED(CONFIG_ARM64))
635 mask |= ARMV8_PMU_EVTYPE_TC | ARMV8_PMU_EVTYPE_TH;
636
637 val &= mask;
638 write_pmevtypern(counter, val);
639}
640
641static void armv8pmu_write_event_type(struct perf_event *event)
642{
643 struct hw_perf_event *hwc = &event->hw;
644 int idx = hwc->idx;
645
646 /*
647 * For chained events, the low counter is programmed to count
648 * the event of interest and the high counter is programmed
649 * with CHAIN event code with filters set to count at all ELs.
650 */
651 if (armv8pmu_event_is_chained(event)) {
652 u32 chain_evt = ARMV8_PMUV3_PERFCTR_CHAIN |
653 ARMV8_PMU_INCLUDE_EL2;
654
655 armv8pmu_write_evtype(idx: idx - 1, val: hwc->config_base);
656 armv8pmu_write_evtype(idx, val: chain_evt);
657 } else {
658 if (idx == ARMV8_IDX_CYCLE_COUNTER)
659 write_pmccfiltr(hwc->config_base);
660 else
661 armv8pmu_write_evtype(idx, val: hwc->config_base);
662 }
663}
664
665static u32 armv8pmu_event_cnten_mask(struct perf_event *event)
666{
667 int counter = ARMV8_IDX_TO_COUNTER(event->hw.idx);
668 u32 mask = BIT(counter);
669
670 if (armv8pmu_event_is_chained(event))
671 mask |= BIT(counter - 1);
672 return mask;
673}
674
675static void armv8pmu_enable_counter(u32 mask)
676{
677 /*
678 * Make sure event configuration register writes are visible before we
679 * enable the counter.
680 * */
681 isb();
682 write_pmcntenset(mask);
683}
684
685static void armv8pmu_enable_event_counter(struct perf_event *event)
686{
687 struct perf_event_attr *attr = &event->attr;
688 u32 mask = armv8pmu_event_cnten_mask(event);
689
690 kvm_set_pmu_events(mask, attr);
691
692 /* We rely on the hypervisor switch code to enable guest counters */
693 if (!kvm_pmu_counter_deferred(attr))
694 armv8pmu_enable_counter(mask);
695}
696
697static void armv8pmu_disable_counter(u32 mask)
698{
699 write_pmcntenclr(mask);
700 /*
701 * Make sure the effects of disabling the counter are visible before we
702 * start configuring the event.
703 */
704 isb();
705}
706
707static void armv8pmu_disable_event_counter(struct perf_event *event)
708{
709 struct perf_event_attr *attr = &event->attr;
710 u32 mask = armv8pmu_event_cnten_mask(event);
711
712 kvm_clr_pmu_events(mask);
713
714 /* We rely on the hypervisor switch code to disable guest counters */
715 if (!kvm_pmu_counter_deferred(attr))
716 armv8pmu_disable_counter(mask);
717}
718
719static void armv8pmu_enable_intens(u32 mask)
720{
721 write_pmintenset(mask);
722}
723
724static void armv8pmu_enable_event_irq(struct perf_event *event)
725{
726 u32 counter = ARMV8_IDX_TO_COUNTER(event->hw.idx);
727 armv8pmu_enable_intens(BIT(counter));
728}
729
730static void armv8pmu_disable_intens(u32 mask)
731{
732 write_pmintenclr(mask);
733 isb();
734 /* Clear the overflow flag in case an interrupt is pending. */
735 write_pmovsclr(mask);
736 isb();
737}
738
739static void armv8pmu_disable_event_irq(struct perf_event *event)
740{
741 u32 counter = ARMV8_IDX_TO_COUNTER(event->hw.idx);
742 armv8pmu_disable_intens(BIT(counter));
743}
744
745static u32 armv8pmu_getreset_flags(void)
746{
747 u32 value;
748
749 /* Read */
750 value = read_pmovsclr();
751
752 /* Write to clear flags */
753 value &= ARMV8_PMU_OVERFLOWED_MASK;
754 write_pmovsclr(value);
755
756 return value;
757}
758
759static void update_pmuserenr(u64 val)
760{
761 lockdep_assert_irqs_disabled();
762
763 /*
764 * The current PMUSERENR_EL0 value might be the value for the guest.
765 * If that's the case, have KVM keep tracking of the register value
766 * for the host EL0 so that KVM can restore it before returning to
767 * the host EL0. Otherwise, update the register now.
768 */
769 if (kvm_set_pmuserenr(val))
770 return;
771
772 write_pmuserenr(val);
773}
774
775static void armv8pmu_disable_user_access(void)
776{
777 update_pmuserenr(val: 0);
778}
779
780static void armv8pmu_enable_user_access(struct arm_pmu *cpu_pmu)
781{
782 int i;
783 struct pmu_hw_events *cpuc = this_cpu_ptr(cpu_pmu->hw_events);
784
785 /* Clear any unused counters to avoid leaking their contents */
786 for_each_clear_bit(i, cpuc->used_mask, cpu_pmu->num_events) {
787 if (i == ARMV8_IDX_CYCLE_COUNTER)
788 write_pmccntr(0);
789 else
790 armv8pmu_write_evcntr(idx: i, value: 0);
791 }
792
793 update_pmuserenr(ARMV8_PMU_USERENR_ER | ARMV8_PMU_USERENR_CR);
794}
795
796static void armv8pmu_enable_event(struct perf_event *event)
797{
798 /*
799 * Enable counter and interrupt, and set the counter to count
800 * the event that we're interested in.
801 */
802 armv8pmu_disable_event_counter(event);
803 armv8pmu_write_event_type(event);
804 armv8pmu_enable_event_irq(event);
805 armv8pmu_enable_event_counter(event);
806}
807
808static void armv8pmu_disable_event(struct perf_event *event)
809{
810 armv8pmu_disable_event_counter(event);
811 armv8pmu_disable_event_irq(event);
812}
813
814static void armv8pmu_start(struct arm_pmu *cpu_pmu)
815{
816 struct perf_event_context *ctx;
817 int nr_user = 0;
818
819 ctx = perf_cpu_task_ctx();
820 if (ctx)
821 nr_user = ctx->nr_user;
822
823 if (sysctl_perf_user_access && nr_user)
824 armv8pmu_enable_user_access(cpu_pmu);
825 else
826 armv8pmu_disable_user_access();
827
828 /* Enable all counters */
829 armv8pmu_pmcr_write(val: armv8pmu_pmcr_read() | ARMV8_PMU_PMCR_E);
830
831 kvm_vcpu_pmu_resync_el0();
832}
833
834static void armv8pmu_stop(struct arm_pmu *cpu_pmu)
835{
836 /* Disable all counters */
837 armv8pmu_pmcr_write(val: armv8pmu_pmcr_read() & ~ARMV8_PMU_PMCR_E);
838}
839
840static irqreturn_t armv8pmu_handle_irq(struct arm_pmu *cpu_pmu)
841{
842 u32 pmovsr;
843 struct perf_sample_data data;
844 struct pmu_hw_events *cpuc = this_cpu_ptr(cpu_pmu->hw_events);
845 struct pt_regs *regs;
846 int idx;
847
848 /*
849 * Get and reset the IRQ flags
850 */
851 pmovsr = armv8pmu_getreset_flags();
852
853 /*
854 * Did an overflow occur?
855 */
856 if (!armv8pmu_has_overflowed(pmovsr))
857 return IRQ_NONE;
858
859 /*
860 * Handle the counter(s) overflow(s)
861 */
862 regs = get_irq_regs();
863
864 /*
865 * Stop the PMU while processing the counter overflows
866 * to prevent skews in group events.
867 */
868 armv8pmu_stop(cpu_pmu);
869 for (idx = 0; idx < cpu_pmu->num_events; ++idx) {
870 struct perf_event *event = cpuc->events[idx];
871 struct hw_perf_event *hwc;
872
873 /* Ignore if we don't have an event. */
874 if (!event)
875 continue;
876
877 /*
878 * We have a single interrupt for all counters. Check that
879 * each counter has overflowed before we process it.
880 */
881 if (!armv8pmu_counter_has_overflowed(pmnc: pmovsr, idx))
882 continue;
883
884 hwc = &event->hw;
885 armpmu_event_update(event);
886 perf_sample_data_init(data: &data, addr: 0, period: hwc->last_period);
887 if (!armpmu_event_set_period(event))
888 continue;
889
890 /*
891 * Perf event overflow will queue the processing of the event as
892 * an irq_work which will be taken care of in the handling of
893 * IPI_IRQ_WORK.
894 */
895 if (perf_event_overflow(event, data: &data, regs))
896 cpu_pmu->disable(event);
897 }
898 armv8pmu_start(cpu_pmu);
899
900 return IRQ_HANDLED;
901}
902
903static int armv8pmu_get_single_idx(struct pmu_hw_events *cpuc,
904 struct arm_pmu *cpu_pmu)
905{
906 int idx;
907
908 for (idx = ARMV8_IDX_COUNTER0; idx < cpu_pmu->num_events; idx++) {
909 if (!test_and_set_bit(nr: idx, addr: cpuc->used_mask))
910 return idx;
911 }
912 return -EAGAIN;
913}
914
915static int armv8pmu_get_chain_idx(struct pmu_hw_events *cpuc,
916 struct arm_pmu *cpu_pmu)
917{
918 int idx;
919
920 /*
921 * Chaining requires two consecutive event counters, where
922 * the lower idx must be even.
923 */
924 for (idx = ARMV8_IDX_COUNTER0 + 1; idx < cpu_pmu->num_events; idx += 2) {
925 if (!test_and_set_bit(nr: idx, addr: cpuc->used_mask)) {
926 /* Check if the preceding even counter is available */
927 if (!test_and_set_bit(nr: idx - 1, addr: cpuc->used_mask))
928 return idx;
929 /* Release the Odd counter */
930 clear_bit(nr: idx, addr: cpuc->used_mask);
931 }
932 }
933 return -EAGAIN;
934}
935
936static int armv8pmu_get_event_idx(struct pmu_hw_events *cpuc,
937 struct perf_event *event)
938{
939 struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu);
940 struct hw_perf_event *hwc = &event->hw;
941 unsigned long evtype = hwc->config_base & ARMV8_PMU_EVTYPE_EVENT;
942
943 /* Always prefer to place a cycle counter into the cycle counter. */
944 if (evtype == ARMV8_PMUV3_PERFCTR_CPU_CYCLES) {
945 if (!test_and_set_bit(ARMV8_IDX_CYCLE_COUNTER, addr: cpuc->used_mask))
946 return ARMV8_IDX_CYCLE_COUNTER;
947 else if (armv8pmu_event_is_64bit(event) &&
948 armv8pmu_event_want_user_access(event) &&
949 !armv8pmu_has_long_event(cpu_pmu))
950 return -EAGAIN;
951 }
952
953 /*
954 * Otherwise use events counters
955 */
956 if (armv8pmu_event_is_chained(event))
957 return armv8pmu_get_chain_idx(cpuc, cpu_pmu);
958 else
959 return armv8pmu_get_single_idx(cpuc, cpu_pmu);
960}
961
962static void armv8pmu_clear_event_idx(struct pmu_hw_events *cpuc,
963 struct perf_event *event)
964{
965 int idx = event->hw.idx;
966
967 clear_bit(nr: idx, addr: cpuc->used_mask);
968 if (armv8pmu_event_is_chained(event))
969 clear_bit(nr: idx - 1, addr: cpuc->used_mask);
970}
971
972static int armv8pmu_user_event_idx(struct perf_event *event)
973{
974 if (!sysctl_perf_user_access || !armv8pmu_event_has_user_read(event))
975 return 0;
976
977 /*
978 * We remap the cycle counter index to 32 to
979 * match the offset applied to the rest of
980 * the counter indices.
981 */
982 if (event->hw.idx == ARMV8_IDX_CYCLE_COUNTER)
983 return ARMV8_IDX_CYCLE_COUNTER_USER;
984
985 return event->hw.idx;
986}
987
988/*
989 * Add an event filter to a given event.
990 */
991static int armv8pmu_set_event_filter(struct hw_perf_event *event,
992 struct perf_event_attr *attr)
993{
994 unsigned long config_base = 0;
995 struct perf_event *perf_event = container_of(attr, struct perf_event,
996 attr);
997 struct arm_pmu *cpu_pmu = to_arm_pmu(perf_event->pmu);
998 u32 th;
999
1000 if (attr->exclude_idle) {
1001 pr_debug("ARM performance counters do not support mode exclusion\n");
1002 return -EOPNOTSUPP;
1003 }
1004
1005 /*
1006 * If we're running in hyp mode, then we *are* the hypervisor.
1007 * Therefore we ignore exclude_hv in this configuration, since
1008 * there's no hypervisor to sample anyway. This is consistent
1009 * with other architectures (x86 and Power).
1010 */
1011 if (is_kernel_in_hyp_mode()) {
1012 if (!attr->exclude_kernel && !attr->exclude_host)
1013 config_base |= ARMV8_PMU_INCLUDE_EL2;
1014 if (attr->exclude_guest)
1015 config_base |= ARMV8_PMU_EXCLUDE_EL1;
1016 if (attr->exclude_host)
1017 config_base |= ARMV8_PMU_EXCLUDE_EL0;
1018 } else {
1019 if (!attr->exclude_hv && !attr->exclude_host)
1020 config_base |= ARMV8_PMU_INCLUDE_EL2;
1021 }
1022
1023 /*
1024 * Filter out !VHE kernels and guest kernels
1025 */
1026 if (attr->exclude_kernel)
1027 config_base |= ARMV8_PMU_EXCLUDE_EL1;
1028
1029 if (attr->exclude_user)
1030 config_base |= ARMV8_PMU_EXCLUDE_EL0;
1031
1032 /*
1033 * If FEAT_PMUv3_TH isn't implemented, then THWIDTH (threshold_max) will
1034 * be 0 and will also trigger this check, preventing it from being used.
1035 */
1036 th = ATTR_CFG_GET_FLD(attr, threshold);
1037 if (th > threshold_max(cpu_pmu)) {
1038 pr_debug("PMU event threshold exceeds max value\n");
1039 return -EINVAL;
1040 }
1041
1042 if (IS_ENABLED(CONFIG_ARM64) && th) {
1043 config_base |= FIELD_PREP(ARMV8_PMU_EVTYPE_TH, th);
1044 config_base |= FIELD_PREP(ARMV8_PMU_EVTYPE_TC,
1045 armv8pmu_event_threshold_control(attr));
1046 }
1047
1048 /*
1049 * Install the filter into config_base as this is used to
1050 * construct the event type.
1051 */
1052 event->config_base = config_base;
1053
1054 return 0;
1055}
1056
1057static void armv8pmu_reset(void *info)
1058{
1059 struct arm_pmu *cpu_pmu = (struct arm_pmu *)info;
1060 u64 pmcr;
1061
1062 /* The counter and interrupt enable registers are unknown at reset. */
1063 armv8pmu_disable_counter(U32_MAX);
1064 armv8pmu_disable_intens(U32_MAX);
1065
1066 /* Clear the counters we flip at guest entry/exit */
1067 kvm_clr_pmu_events(U32_MAX);
1068
1069 /*
1070 * Initialize & Reset PMNC. Request overflow interrupt for
1071 * 64 bit cycle counter but cheat in armv8pmu_write_counter().
1072 */
1073 pmcr = ARMV8_PMU_PMCR_P | ARMV8_PMU_PMCR_C | ARMV8_PMU_PMCR_LC;
1074
1075 /* Enable long event counter support where available */
1076 if (armv8pmu_has_long_event(cpu_pmu))
1077 pmcr |= ARMV8_PMU_PMCR_LP;
1078
1079 armv8pmu_pmcr_write(val: pmcr);
1080}
1081
1082static int __armv8_pmuv3_map_event_id(struct arm_pmu *armpmu,
1083 struct perf_event *event)
1084{
1085 if (event->attr.type == PERF_TYPE_HARDWARE &&
1086 event->attr.config == PERF_COUNT_HW_BRANCH_INSTRUCTIONS) {
1087
1088 if (test_bit(ARMV8_PMUV3_PERFCTR_PC_WRITE_RETIRED,
1089 armpmu->pmceid_bitmap))
1090 return ARMV8_PMUV3_PERFCTR_PC_WRITE_RETIRED;
1091
1092 if (test_bit(ARMV8_PMUV3_PERFCTR_BR_RETIRED,
1093 armpmu->pmceid_bitmap))
1094 return ARMV8_PMUV3_PERFCTR_BR_RETIRED;
1095
1096 return HW_OP_UNSUPPORTED;
1097 }
1098
1099 return armpmu_map_event(event, &armv8_pmuv3_perf_map,
1100 &armv8_pmuv3_perf_cache_map,
1101 ARMV8_PMU_EVTYPE_EVENT);
1102}
1103
1104static int __armv8_pmuv3_map_event(struct perf_event *event,
1105 const unsigned (*extra_event_map)
1106 [PERF_COUNT_HW_MAX],
1107 const unsigned (*extra_cache_map)
1108 [PERF_COUNT_HW_CACHE_MAX]
1109 [PERF_COUNT_HW_CACHE_OP_MAX]
1110 [PERF_COUNT_HW_CACHE_RESULT_MAX])
1111{
1112 int hw_event_id;
1113 struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
1114
1115 hw_event_id = __armv8_pmuv3_map_event_id(armpmu, event);
1116
1117 /*
1118 * CHAIN events only work when paired with an adjacent counter, and it
1119 * never makes sense for a user to open one in isolation, as they'll be
1120 * rotated arbitrarily.
1121 */
1122 if (hw_event_id == ARMV8_PMUV3_PERFCTR_CHAIN)
1123 return -EINVAL;
1124
1125 if (armv8pmu_event_is_64bit(event))
1126 event->hw.flags |= ARMPMU_EVT_64BIT;
1127
1128 /*
1129 * User events must be allocated into a single counter, and so
1130 * must not be chained.
1131 *
1132 * Most 64-bit events require long counter support, but 64-bit
1133 * CPU_CYCLES events can be placed into the dedicated cycle
1134 * counter when this is free.
1135 */
1136 if (armv8pmu_event_want_user_access(event)) {
1137 if (!(event->attach_state & PERF_ATTACH_TASK))
1138 return -EINVAL;
1139 if (armv8pmu_event_is_64bit(event) &&
1140 (hw_event_id != ARMV8_PMUV3_PERFCTR_CPU_CYCLES) &&
1141 !armv8pmu_has_long_event(cpu_pmu: armpmu))
1142 return -EOPNOTSUPP;
1143
1144 event->hw.flags |= PERF_EVENT_FLAG_USER_READ_CNT;
1145 }
1146
1147 /* Only expose micro/arch events supported by this PMU */
1148 if ((hw_event_id > 0) && (hw_event_id < ARMV8_PMUV3_MAX_COMMON_EVENTS)
1149 && test_bit(hw_event_id, armpmu->pmceid_bitmap)) {
1150 return hw_event_id;
1151 }
1152
1153 return armpmu_map_event(event, extra_event_map, extra_cache_map,
1154 ARMV8_PMU_EVTYPE_EVENT);
1155}
1156
1157static int armv8_pmuv3_map_event(struct perf_event *event)
1158{
1159 return __armv8_pmuv3_map_event(event, NULL, NULL);
1160}
1161
1162static int armv8_a53_map_event(struct perf_event *event)
1163{
1164 return __armv8_pmuv3_map_event(event, NULL, extra_cache_map: &armv8_a53_perf_cache_map);
1165}
1166
1167static int armv8_a57_map_event(struct perf_event *event)
1168{
1169 return __armv8_pmuv3_map_event(event, NULL, extra_cache_map: &armv8_a57_perf_cache_map);
1170}
1171
1172static int armv8_a73_map_event(struct perf_event *event)
1173{
1174 return __armv8_pmuv3_map_event(event, NULL, extra_cache_map: &armv8_a73_perf_cache_map);
1175}
1176
1177static int armv8_thunder_map_event(struct perf_event *event)
1178{
1179 return __armv8_pmuv3_map_event(event, NULL,
1180 extra_cache_map: &armv8_thunder_perf_cache_map);
1181}
1182
1183static int armv8_vulcan_map_event(struct perf_event *event)
1184{
1185 return __armv8_pmuv3_map_event(event, NULL,
1186 extra_cache_map: &armv8_vulcan_perf_cache_map);
1187}
1188
1189struct armv8pmu_probe_info {
1190 struct arm_pmu *pmu;
1191 bool present;
1192};
1193
1194static void __armv8pmu_probe_pmu(void *info)
1195{
1196 struct armv8pmu_probe_info *probe = info;
1197 struct arm_pmu *cpu_pmu = probe->pmu;
1198 u64 pmceid_raw[2];
1199 u32 pmceid[2];
1200 int pmuver;
1201
1202 pmuver = read_pmuver();
1203 if (!pmuv3_implemented(pmuver))
1204 return;
1205
1206 cpu_pmu->pmuver = pmuver;
1207 probe->present = true;
1208
1209 /* Read the nb of CNTx counters supported from PMNC */
1210 cpu_pmu->num_events = FIELD_GET(ARMV8_PMU_PMCR_N, armv8pmu_pmcr_read());
1211
1212 /* Add the CPU cycles counter */
1213 cpu_pmu->num_events += 1;
1214
1215 pmceid[0] = pmceid_raw[0] = read_pmceid0();
1216 pmceid[1] = pmceid_raw[1] = read_pmceid1();
1217
1218 bitmap_from_arr32(cpu_pmu->pmceid_bitmap,
1219 pmceid, ARMV8_PMUV3_MAX_COMMON_EVENTS);
1220
1221 pmceid[0] = pmceid_raw[0] >> 32;
1222 pmceid[1] = pmceid_raw[1] >> 32;
1223
1224 bitmap_from_arr32(cpu_pmu->pmceid_ext_bitmap,
1225 pmceid, ARMV8_PMUV3_MAX_COMMON_EVENTS);
1226
1227 /* store PMMIR register for sysfs */
1228 if (is_pmuv3p4(pmuver))
1229 cpu_pmu->reg_pmmir = read_pmmir();
1230 else
1231 cpu_pmu->reg_pmmir = 0;
1232}
1233
1234static int armv8pmu_probe_pmu(struct arm_pmu *cpu_pmu)
1235{
1236 struct armv8pmu_probe_info probe = {
1237 .pmu = cpu_pmu,
1238 .present = false,
1239 };
1240 int ret;
1241
1242 ret = smp_call_function_any(mask: &cpu_pmu->supported_cpus,
1243 func: __armv8pmu_probe_pmu,
1244 info: &probe, wait: 1);
1245 if (ret)
1246 return ret;
1247
1248 return probe.present ? 0 : -ENODEV;
1249}
1250
1251static void armv8pmu_disable_user_access_ipi(void *unused)
1252{
1253 armv8pmu_disable_user_access();
1254}
1255
1256static int armv8pmu_proc_user_access_handler(struct ctl_table *table, int write,
1257 void *buffer, size_t *lenp, loff_t *ppos)
1258{
1259 int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
1260 if (ret || !write || sysctl_perf_user_access)
1261 return ret;
1262
1263 on_each_cpu(func: armv8pmu_disable_user_access_ipi, NULL, wait: 1);
1264 return 0;
1265}
1266
1267static struct ctl_table armv8_pmu_sysctl_table[] = {
1268 {
1269 .procname = "perf_user_access",
1270 .data = &sysctl_perf_user_access,
1271 .maxlen = sizeof(unsigned int),
1272 .mode = 0644,
1273 .proc_handler = armv8pmu_proc_user_access_handler,
1274 .extra1 = SYSCTL_ZERO,
1275 .extra2 = SYSCTL_ONE,
1276 },
1277};
1278
1279static void armv8_pmu_register_sysctl_table(void)
1280{
1281 static u32 tbl_registered = 0;
1282
1283 if (!cmpxchg_relaxed(&tbl_registered, 0, 1))
1284 register_sysctl("kernel", armv8_pmu_sysctl_table);
1285}
1286
1287static int armv8_pmu_init(struct arm_pmu *cpu_pmu, char *name,
1288 int (*map_event)(struct perf_event *event))
1289{
1290 int ret = armv8pmu_probe_pmu(cpu_pmu);
1291 if (ret)
1292 return ret;
1293
1294 cpu_pmu->handle_irq = armv8pmu_handle_irq;
1295 cpu_pmu->enable = armv8pmu_enable_event;
1296 cpu_pmu->disable = armv8pmu_disable_event;
1297 cpu_pmu->read_counter = armv8pmu_read_counter;
1298 cpu_pmu->write_counter = armv8pmu_write_counter;
1299 cpu_pmu->get_event_idx = armv8pmu_get_event_idx;
1300 cpu_pmu->clear_event_idx = armv8pmu_clear_event_idx;
1301 cpu_pmu->start = armv8pmu_start;
1302 cpu_pmu->stop = armv8pmu_stop;
1303 cpu_pmu->reset = armv8pmu_reset;
1304 cpu_pmu->set_event_filter = armv8pmu_set_event_filter;
1305
1306 cpu_pmu->pmu.event_idx = armv8pmu_user_event_idx;
1307
1308 cpu_pmu->name = name;
1309 cpu_pmu->map_event = map_event;
1310 cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_EVENTS] = &armv8_pmuv3_events_attr_group;
1311 cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_FORMATS] = &armv8_pmuv3_format_attr_group;
1312 cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_CAPS] = &armv8_pmuv3_caps_attr_group;
1313 armv8_pmu_register_sysctl_table();
1314 return 0;
1315}
1316
1317#define PMUV3_INIT_SIMPLE(name) \
1318static int name##_pmu_init(struct arm_pmu *cpu_pmu) \
1319{ \
1320 return armv8_pmu_init(cpu_pmu, #name, armv8_pmuv3_map_event); \
1321}
1322
1323#define PMUV3_INIT_MAP_EVENT(name, map_event) \
1324static int name##_pmu_init(struct arm_pmu *cpu_pmu) \
1325{ \
1326 return armv8_pmu_init(cpu_pmu, #name, map_event); \
1327}
1328
1329PMUV3_INIT_SIMPLE(armv8_pmuv3)
1330
1331PMUV3_INIT_SIMPLE(armv8_cortex_a34)
1332PMUV3_INIT_SIMPLE(armv8_cortex_a55)
1333PMUV3_INIT_SIMPLE(armv8_cortex_a65)
1334PMUV3_INIT_SIMPLE(armv8_cortex_a75)
1335PMUV3_INIT_SIMPLE(armv8_cortex_a76)
1336PMUV3_INIT_SIMPLE(armv8_cortex_a77)
1337PMUV3_INIT_SIMPLE(armv8_cortex_a78)
1338PMUV3_INIT_SIMPLE(armv9_cortex_a510)
1339PMUV3_INIT_SIMPLE(armv9_cortex_a520)
1340PMUV3_INIT_SIMPLE(armv9_cortex_a710)
1341PMUV3_INIT_SIMPLE(armv9_cortex_a715)
1342PMUV3_INIT_SIMPLE(armv9_cortex_a720)
1343PMUV3_INIT_SIMPLE(armv8_cortex_x1)
1344PMUV3_INIT_SIMPLE(armv9_cortex_x2)
1345PMUV3_INIT_SIMPLE(armv9_cortex_x3)
1346PMUV3_INIT_SIMPLE(armv9_cortex_x4)
1347PMUV3_INIT_SIMPLE(armv8_neoverse_e1)
1348PMUV3_INIT_SIMPLE(armv8_neoverse_n1)
1349PMUV3_INIT_SIMPLE(armv9_neoverse_n2)
1350PMUV3_INIT_SIMPLE(armv8_neoverse_v1)
1351
1352PMUV3_INIT_SIMPLE(armv8_nvidia_carmel)
1353PMUV3_INIT_SIMPLE(armv8_nvidia_denver)
1354
1355PMUV3_INIT_MAP_EVENT(armv8_cortex_a35, armv8_a53_map_event)
1356PMUV3_INIT_MAP_EVENT(armv8_cortex_a53, armv8_a53_map_event)
1357PMUV3_INIT_MAP_EVENT(armv8_cortex_a57, armv8_a57_map_event)
1358PMUV3_INIT_MAP_EVENT(armv8_cortex_a72, armv8_a57_map_event)
1359PMUV3_INIT_MAP_EVENT(armv8_cortex_a73, armv8_a73_map_event)
1360PMUV3_INIT_MAP_EVENT(armv8_cavium_thunder, armv8_thunder_map_event)
1361PMUV3_INIT_MAP_EVENT(armv8_brcm_vulcan, armv8_vulcan_map_event)
1362
1363static const struct of_device_id armv8_pmu_of_device_ids[] = {
1364 {.compatible = "arm,armv8-pmuv3", .data = armv8_pmuv3_pmu_init},
1365 {.compatible = "arm,cortex-a34-pmu", .data = armv8_cortex_a34_pmu_init},
1366 {.compatible = "arm,cortex-a35-pmu", .data = armv8_cortex_a35_pmu_init},
1367 {.compatible = "arm,cortex-a53-pmu", .data = armv8_cortex_a53_pmu_init},
1368 {.compatible = "arm,cortex-a55-pmu", .data = armv8_cortex_a55_pmu_init},
1369 {.compatible = "arm,cortex-a57-pmu", .data = armv8_cortex_a57_pmu_init},
1370 {.compatible = "arm,cortex-a65-pmu", .data = armv8_cortex_a65_pmu_init},
1371 {.compatible = "arm,cortex-a72-pmu", .data = armv8_cortex_a72_pmu_init},
1372 {.compatible = "arm,cortex-a73-pmu", .data = armv8_cortex_a73_pmu_init},
1373 {.compatible = "arm,cortex-a75-pmu", .data = armv8_cortex_a75_pmu_init},
1374 {.compatible = "arm,cortex-a76-pmu", .data = armv8_cortex_a76_pmu_init},
1375 {.compatible = "arm,cortex-a77-pmu", .data = armv8_cortex_a77_pmu_init},
1376 {.compatible = "arm,cortex-a78-pmu", .data = armv8_cortex_a78_pmu_init},
1377 {.compatible = "arm,cortex-a510-pmu", .data = armv9_cortex_a510_pmu_init},
1378 {.compatible = "arm,cortex-a520-pmu", .data = armv9_cortex_a520_pmu_init},
1379 {.compatible = "arm,cortex-a710-pmu", .data = armv9_cortex_a710_pmu_init},
1380 {.compatible = "arm,cortex-a715-pmu", .data = armv9_cortex_a715_pmu_init},
1381 {.compatible = "arm,cortex-a720-pmu", .data = armv9_cortex_a720_pmu_init},
1382 {.compatible = "arm,cortex-x1-pmu", .data = armv8_cortex_x1_pmu_init},
1383 {.compatible = "arm,cortex-x2-pmu", .data = armv9_cortex_x2_pmu_init},
1384 {.compatible = "arm,cortex-x3-pmu", .data = armv9_cortex_x3_pmu_init},
1385 {.compatible = "arm,cortex-x4-pmu", .data = armv9_cortex_x4_pmu_init},
1386 {.compatible = "arm,neoverse-e1-pmu", .data = armv8_neoverse_e1_pmu_init},
1387 {.compatible = "arm,neoverse-n1-pmu", .data = armv8_neoverse_n1_pmu_init},
1388 {.compatible = "arm,neoverse-n2-pmu", .data = armv9_neoverse_n2_pmu_init},
1389 {.compatible = "arm,neoverse-v1-pmu", .data = armv8_neoverse_v1_pmu_init},
1390 {.compatible = "cavium,thunder-pmu", .data = armv8_cavium_thunder_pmu_init},
1391 {.compatible = "brcm,vulcan-pmu", .data = armv8_brcm_vulcan_pmu_init},
1392 {.compatible = "nvidia,carmel-pmu", .data = armv8_nvidia_carmel_pmu_init},
1393 {.compatible = "nvidia,denver-pmu", .data = armv8_nvidia_denver_pmu_init},
1394 {},
1395};
1396
1397static int armv8_pmu_device_probe(struct platform_device *pdev)
1398{
1399 return arm_pmu_device_probe(pdev, armv8_pmu_of_device_ids, NULL);
1400}
1401
1402static struct platform_driver armv8_pmu_driver = {
1403 .driver = {
1404 .name = ARMV8_PMU_PDEV_NAME,
1405 .of_match_table = armv8_pmu_of_device_ids,
1406 .suppress_bind_attrs = true,
1407 },
1408 .probe = armv8_pmu_device_probe,
1409};
1410
1411static int __init armv8_pmu_driver_init(void)
1412{
1413 int ret;
1414
1415 if (acpi_disabled)
1416 ret = platform_driver_register(&armv8_pmu_driver);
1417 else
1418 ret = arm_pmu_acpi_probe(armv8_pmuv3_pmu_init);
1419
1420 if (!ret)
1421 lockup_detector_retry_init();
1422
1423 return ret;
1424}
1425device_initcall(armv8_pmu_driver_init)
1426
1427void arch_perf_update_userpage(struct perf_event *event,
1428 struct perf_event_mmap_page *userpg, u64 now)
1429{
1430 struct clock_read_data *rd;
1431 unsigned int seq;
1432 u64 ns;
1433
1434 userpg->cap_user_time = 0;
1435 userpg->cap_user_time_zero = 0;
1436 userpg->cap_user_time_short = 0;
1437 userpg->cap_user_rdpmc = armv8pmu_event_has_user_read(event);
1438
1439 if (userpg->cap_user_rdpmc) {
1440 if (event->hw.flags & ARMPMU_EVT_64BIT)
1441 userpg->pmc_width = 64;
1442 else
1443 userpg->pmc_width = 32;
1444 }
1445
1446 do {
1447 rd = sched_clock_read_begin(&seq);
1448
1449 if (rd->read_sched_clock != arch_timer_read_counter)
1450 return;
1451
1452 userpg->time_mult = rd->mult;
1453 userpg->time_shift = rd->shift;
1454 userpg->time_zero = rd->epoch_ns;
1455 userpg->time_cycles = rd->epoch_cyc;
1456 userpg->time_mask = rd->sched_clock_mask;
1457
1458 /*
1459 * Subtract the cycle base, such that software that
1460 * doesn't know about cap_user_time_short still 'works'
1461 * assuming no wraps.
1462 */
1463 ns = mul_u64_u32_shr(a: rd->epoch_cyc, mul: rd->mult, shift: rd->shift);
1464 userpg->time_zero -= ns;
1465
1466 } while (sched_clock_read_retry(seq));
1467
1468 userpg->time_offset = userpg->time_zero - now;
1469
1470 /*
1471 * time_shift is not expected to be greater than 31 due to
1472 * the original published conversion algorithm shifting a
1473 * 32-bit value (now specifies a 64-bit value) - refer
1474 * perf_event_mmap_page documentation in perf_event.h.
1475 */
1476 if (userpg->time_shift == 32) {
1477 userpg->time_shift = 31;
1478 userpg->time_mult >>= 1;
1479 }
1480
1481 /*
1482 * Internal timekeeping for enabled/running/stopped times
1483 * is always computed with the sched_clock.
1484 */
1485 userpg->cap_user_time = 1;
1486 userpg->cap_user_time_zero = 1;
1487 userpg->cap_user_time_short = 1;
1488}
1489

source code of linux/drivers/perf/arm_pmuv3.c