1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * RISC-V performance counter support. 4 * 5 * Copyright (C) 2021 Western Digital Corporation or its affiliates. 6 * 7 * This code is based on ARM perf event code which is in turn based on 8 * sparc64 and x86 code. 9 */ 10 11 #define pr_fmt(fmt) "riscv-pmu-sbi: " fmt 12 13 #include <linux/mod_devicetable.h> 14 #include <linux/perf/riscv_pmu.h> 15 #include <linux/platform_device.h> 16 #include <linux/irq.h> 17 #include <linux/irqdomain.h> 18 #include <linux/of_irq.h> 19 #include <linux/of.h> 20 #include <linux/cpu_pm.h> 21 #include <linux/sched/clock.h> 22 23 #include <asm/errata_list.h> 24 #include <asm/sbi.h> 25 #include <asm/hwcap.h> 26 27 PMU_FORMAT_ATTR(event, "config:0-47"); 28 PMU_FORMAT_ATTR(firmware, "config:63"); 29 30 static struct attribute *riscv_arch_formats_attr[] = { 31 &format_attr_event.attr, 32 &format_attr_firmware.attr, 33 NULL, 34 }; 35 36 static struct attribute_group riscv_pmu_format_group = { 37 .name = "format", 38 .attrs = riscv_arch_formats_attr, 39 }; 40 41 static const struct attribute_group *riscv_pmu_attr_groups[] = { 42 &riscv_pmu_format_group, 43 NULL, 44 }; 45 46 /* 47 * RISC-V doesn't have hetergenous harts yet. This need to be part of 48 * per_cpu in case of harts with different pmu counters 49 */ 50 static union sbi_pmu_ctr_info *pmu_ctr_list; 51 static bool riscv_pmu_use_irq; 52 static unsigned int riscv_pmu_irq_num; 53 static unsigned int riscv_pmu_irq; 54 55 struct sbi_pmu_event_data { 56 union { 57 union { 58 struct hw_gen_event { 59 uint32_t event_code:16; 60 uint32_t event_type:4; 61 uint32_t reserved:12; 62 } hw_gen_event; 63 struct hw_cache_event { 64 uint32_t result_id:1; 65 uint32_t op_id:2; 66 uint32_t cache_id:13; 67 uint32_t event_type:4; 68 uint32_t reserved:12; 69 } hw_cache_event; 70 }; 71 uint32_t event_idx; 72 }; 73 }; 74 75 static const struct sbi_pmu_event_data pmu_hw_event_map[] = { 76 [PERF_COUNT_HW_CPU_CYCLES] = {.hw_gen_event = { 77 SBI_PMU_HW_CPU_CYCLES, 78 SBI_PMU_EVENT_TYPE_HW, 0}}, 79 [PERF_COUNT_HW_INSTRUCTIONS] = {.hw_gen_event = { 80 SBI_PMU_HW_INSTRUCTIONS, 81 SBI_PMU_EVENT_TYPE_HW, 0}}, 82 [PERF_COUNT_HW_CACHE_REFERENCES] = {.hw_gen_event = { 83 SBI_PMU_HW_CACHE_REFERENCES, 84 SBI_PMU_EVENT_TYPE_HW, 0}}, 85 [PERF_COUNT_HW_CACHE_MISSES] = {.hw_gen_event = { 86 SBI_PMU_HW_CACHE_MISSES, 87 SBI_PMU_EVENT_TYPE_HW, 0}}, 88 [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = {.hw_gen_event = { 89 SBI_PMU_HW_BRANCH_INSTRUCTIONS, 90 SBI_PMU_EVENT_TYPE_HW, 0}}, 91 [PERF_COUNT_HW_BRANCH_MISSES] = {.hw_gen_event = { 92 SBI_PMU_HW_BRANCH_MISSES, 93 SBI_PMU_EVENT_TYPE_HW, 0}}, 94 [PERF_COUNT_HW_BUS_CYCLES] = {.hw_gen_event = { 95 SBI_PMU_HW_BUS_CYCLES, 96 SBI_PMU_EVENT_TYPE_HW, 0}}, 97 [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = {.hw_gen_event = { 98 SBI_PMU_HW_STALLED_CYCLES_FRONTEND, 99 SBI_PMU_EVENT_TYPE_HW, 0}}, 100 [PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = {.hw_gen_event = { 101 SBI_PMU_HW_STALLED_CYCLES_BACKEND, 102 SBI_PMU_EVENT_TYPE_HW, 0}}, 103 [PERF_COUNT_HW_REF_CPU_CYCLES] = {.hw_gen_event = { 104 SBI_PMU_HW_REF_CPU_CYCLES, 105 SBI_PMU_EVENT_TYPE_HW, 0}}, 106 }; 107 108 #define C(x) PERF_COUNT_HW_CACHE_##x 109 static const struct sbi_pmu_event_data pmu_cache_event_map[PERF_COUNT_HW_CACHE_MAX] 110 [PERF_COUNT_HW_CACHE_OP_MAX] 111 [PERF_COUNT_HW_CACHE_RESULT_MAX] = { 112 [C(L1D)] = { 113 [C(OP_READ)] = { 114 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 115 C(OP_READ), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 116 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 117 C(OP_READ), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 118 }, 119 [C(OP_WRITE)] = { 120 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 121 C(OP_WRITE), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 122 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 123 C(OP_WRITE), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 124 }, 125 [C(OP_PREFETCH)] = { 126 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 127 C(OP_PREFETCH), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 128 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 129 C(OP_PREFETCH), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 130 }, 131 }, 132 [C(L1I)] = { 133 [C(OP_READ)] = { 134 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 135 C(OP_READ), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 136 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), C(OP_READ), 137 C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 138 }, 139 [C(OP_WRITE)] = { 140 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 141 C(OP_WRITE), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 142 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 143 C(OP_WRITE), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 144 }, 145 [C(OP_PREFETCH)] = { 146 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 147 C(OP_PREFETCH), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 148 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 149 C(OP_PREFETCH), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 150 }, 151 }, 152 [C(LL)] = { 153 [C(OP_READ)] = { 154 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 155 C(OP_READ), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 156 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 157 C(OP_READ), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 158 }, 159 [C(OP_WRITE)] = { 160 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 161 C(OP_WRITE), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 162 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 163 C(OP_WRITE), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 164 }, 165 [C(OP_PREFETCH)] = { 166 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 167 C(OP_PREFETCH), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 168 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 169 C(OP_PREFETCH), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 170 }, 171 }, 172 [C(DTLB)] = { 173 [C(OP_READ)] = { 174 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 175 C(OP_READ), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 176 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 177 C(OP_READ), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 178 }, 179 [C(OP_WRITE)] = { 180 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 181 C(OP_WRITE), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 182 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 183 C(OP_WRITE), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 184 }, 185 [C(OP_PREFETCH)] = { 186 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 187 C(OP_PREFETCH), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 188 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 189 C(OP_PREFETCH), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 190 }, 191 }, 192 [C(ITLB)] = { 193 [C(OP_READ)] = { 194 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 195 C(OP_READ), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 196 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 197 C(OP_READ), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 198 }, 199 [C(OP_WRITE)] = { 200 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 201 C(OP_WRITE), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 202 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 203 C(OP_WRITE), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 204 }, 205 [C(OP_PREFETCH)] = { 206 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 207 C(OP_PREFETCH), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 208 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 209 C(OP_PREFETCH), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 210 }, 211 }, 212 [C(BPU)] = { 213 [C(OP_READ)] = { 214 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 215 C(OP_READ), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 216 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 217 C(OP_READ), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 218 }, 219 [C(OP_WRITE)] = { 220 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 221 C(OP_WRITE), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 222 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 223 C(OP_WRITE), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 224 }, 225 [C(OP_PREFETCH)] = { 226 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 227 C(OP_PREFETCH), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 228 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 229 C(OP_PREFETCH), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 230 }, 231 }, 232 [C(NODE)] = { 233 [C(OP_READ)] = { 234 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 235 C(OP_READ), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 236 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 237 C(OP_READ), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 238 }, 239 [C(OP_WRITE)] = { 240 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 241 C(OP_WRITE), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 242 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 243 C(OP_WRITE), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 244 }, 245 [C(OP_PREFETCH)] = { 246 [C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS), 247 C(OP_PREFETCH), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 248 [C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), 249 C(OP_PREFETCH), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}}, 250 }, 251 }, 252 }; 253 254 static int pmu_sbi_ctr_get_width(int idx) 255 { 256 return pmu_ctr_list[idx].width; 257 } 258 259 static bool pmu_sbi_ctr_is_fw(int cidx) 260 { 261 union sbi_pmu_ctr_info *info; 262 263 info = &pmu_ctr_list[cidx]; 264 if (!info) 265 return false; 266 267 return (info->type == SBI_PMU_CTR_TYPE_FW) ? true : false; 268 } 269 270 static int pmu_sbi_ctr_get_idx(struct perf_event *event) 271 { 272 struct hw_perf_event *hwc = &event->hw; 273 struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu); 274 struct cpu_hw_events *cpuc = this_cpu_ptr(rvpmu->hw_events); 275 struct sbiret ret; 276 int idx; 277 uint64_t cbase = 0; 278 unsigned long cflags = 0; 279 280 if (event->attr.exclude_kernel) 281 cflags |= SBI_PMU_CFG_FLAG_SET_SINH; 282 if (event->attr.exclude_user) 283 cflags |= SBI_PMU_CFG_FLAG_SET_UINH; 284 285 /* retrieve the available counter index */ 286 #if defined(CONFIG_32BIT) 287 ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_CFG_MATCH, cbase, 288 rvpmu->cmask, cflags, hwc->event_base, hwc->config, 289 hwc->config >> 32); 290 #else 291 ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_CFG_MATCH, cbase, 292 rvpmu->cmask, cflags, hwc->event_base, hwc->config, 0); 293 #endif 294 if (ret.error) { 295 pr_debug("Not able to find a counter for event %lx config %llx\n", 296 hwc->event_base, hwc->config); 297 return sbi_err_map_linux_errno(ret.error); 298 } 299 300 idx = ret.value; 301 if (!test_bit(idx, &rvpmu->cmask) || !pmu_ctr_list[idx].value) 302 return -ENOENT; 303 304 /* Additional sanity check for the counter id */ 305 if (pmu_sbi_ctr_is_fw(idx)) { 306 if (!test_and_set_bit(idx, cpuc->used_fw_ctrs)) 307 return idx; 308 } else { 309 if (!test_and_set_bit(idx, cpuc->used_hw_ctrs)) 310 return idx; 311 } 312 313 return -ENOENT; 314 } 315 316 static void pmu_sbi_ctr_clear_idx(struct perf_event *event) 317 { 318 319 struct hw_perf_event *hwc = &event->hw; 320 struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu); 321 struct cpu_hw_events *cpuc = this_cpu_ptr(rvpmu->hw_events); 322 int idx = hwc->idx; 323 324 if (pmu_sbi_ctr_is_fw(idx)) 325 clear_bit(idx, cpuc->used_fw_ctrs); 326 else 327 clear_bit(idx, cpuc->used_hw_ctrs); 328 } 329 330 static int pmu_event_find_cache(u64 config) 331 { 332 unsigned int cache_type, cache_op, cache_result, ret; 333 334 cache_type = (config >> 0) & 0xff; 335 if (cache_type >= PERF_COUNT_HW_CACHE_MAX) 336 return -EINVAL; 337 338 cache_op = (config >> 8) & 0xff; 339 if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX) 340 return -EINVAL; 341 342 cache_result = (config >> 16) & 0xff; 343 if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX) 344 return -EINVAL; 345 346 ret = pmu_cache_event_map[cache_type][cache_op][cache_result].event_idx; 347 348 return ret; 349 } 350 351 static bool pmu_sbi_is_fw_event(struct perf_event *event) 352 { 353 u32 type = event->attr.type; 354 u64 config = event->attr.config; 355 356 if ((type == PERF_TYPE_RAW) && ((config >> 63) == 1)) 357 return true; 358 else 359 return false; 360 } 361 362 static int pmu_sbi_event_map(struct perf_event *event, u64 *econfig) 363 { 364 u32 type = event->attr.type; 365 u64 config = event->attr.config; 366 int bSoftware; 367 u64 raw_config_val; 368 int ret; 369 370 switch (type) { 371 case PERF_TYPE_HARDWARE: 372 if (config >= PERF_COUNT_HW_MAX) 373 return -EINVAL; 374 ret = pmu_hw_event_map[event->attr.config].event_idx; 375 break; 376 case PERF_TYPE_HW_CACHE: 377 ret = pmu_event_find_cache(config); 378 break; 379 case PERF_TYPE_RAW: 380 /* 381 * As per SBI specification, the upper 16 bits must be unused for 382 * a raw event. Use the MSB (63b) to distinguish between hardware 383 * raw event and firmware events. 384 */ 385 bSoftware = config >> 63; 386 raw_config_val = config & RISCV_PMU_RAW_EVENT_MASK; 387 if (bSoftware) { 388 if (raw_config_val < SBI_PMU_FW_MAX) 389 ret = (raw_config_val & 0xFFFF) | 390 (SBI_PMU_EVENT_TYPE_FW << 16); 391 else 392 return -EINVAL; 393 } else { 394 ret = RISCV_PMU_RAW_EVENT_IDX; 395 *econfig = raw_config_val; 396 } 397 break; 398 default: 399 ret = -EINVAL; 400 break; 401 } 402 403 return ret; 404 } 405 406 static u64 pmu_sbi_ctr_read(struct perf_event *event) 407 { 408 struct hw_perf_event *hwc = &event->hw; 409 int idx = hwc->idx; 410 struct sbiret ret; 411 union sbi_pmu_ctr_info info; 412 u64 val = 0; 413 414 if (pmu_sbi_is_fw_event(event)) { 415 ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_FW_READ, 416 hwc->idx, 0, 0, 0, 0, 0); 417 if (!ret.error) 418 val = ret.value; 419 } else { 420 info = pmu_ctr_list[idx]; 421 val = riscv_pmu_ctr_read_csr(info.csr); 422 if (IS_ENABLED(CONFIG_32BIT)) 423 val = ((u64)riscv_pmu_ctr_read_csr(info.csr + 0x80)) << 31 | val; 424 } 425 426 return val; 427 } 428 429 static void pmu_sbi_ctr_start(struct perf_event *event, u64 ival) 430 { 431 struct sbiret ret; 432 struct hw_perf_event *hwc = &event->hw; 433 unsigned long flag = SBI_PMU_START_FLAG_SET_INIT_VALUE; 434 435 #if defined(CONFIG_32BIT) 436 ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, hwc->idx, 437 1, flag, ival, ival >> 32, 0); 438 #else 439 ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, hwc->idx, 440 1, flag, ival, 0, 0); 441 #endif 442 if (ret.error && (ret.error != SBI_ERR_ALREADY_STARTED)) 443 pr_err("Starting counter idx %d failed with error %d\n", 444 hwc->idx, sbi_err_map_linux_errno(ret.error)); 445 } 446 447 static void pmu_sbi_ctr_stop(struct perf_event *event, unsigned long flag) 448 { 449 struct sbiret ret; 450 struct hw_perf_event *hwc = &event->hw; 451 452 ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_STOP, hwc->idx, 1, flag, 0, 0, 0); 453 if (ret.error && (ret.error != SBI_ERR_ALREADY_STOPPED) && 454 flag != SBI_PMU_STOP_FLAG_RESET) 455 pr_err("Stopping counter idx %d failed with error %d\n", 456 hwc->idx, sbi_err_map_linux_errno(ret.error)); 457 } 458 459 static int pmu_sbi_find_num_ctrs(void) 460 { 461 struct sbiret ret; 462 463 ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_NUM_COUNTERS, 0, 0, 0, 0, 0, 0); 464 if (!ret.error) 465 return ret.value; 466 else 467 return sbi_err_map_linux_errno(ret.error); 468 } 469 470 static int pmu_sbi_get_ctrinfo(int nctr, unsigned long *mask) 471 { 472 struct sbiret ret; 473 int i, num_hw_ctr = 0, num_fw_ctr = 0; 474 union sbi_pmu_ctr_info cinfo; 475 476 pmu_ctr_list = kcalloc(nctr, sizeof(*pmu_ctr_list), GFP_KERNEL); 477 if (!pmu_ctr_list) 478 return -ENOMEM; 479 480 for (i = 0; i < nctr; i++) { 481 ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_GET_INFO, i, 0, 0, 0, 0, 0); 482 if (ret.error) 483 /* The logical counter ids are not expected to be contiguous */ 484 continue; 485 486 *mask |= BIT(i); 487 488 cinfo.value = ret.value; 489 if (cinfo.type == SBI_PMU_CTR_TYPE_FW) 490 num_fw_ctr++; 491 else 492 num_hw_ctr++; 493 pmu_ctr_list[i].value = cinfo.value; 494 } 495 496 pr_info("%d firmware and %d hardware counters\n", num_fw_ctr, num_hw_ctr); 497 498 return 0; 499 } 500 501 static inline void pmu_sbi_stop_all(struct riscv_pmu *pmu) 502 { 503 /* 504 * No need to check the error because we are disabling all the counters 505 * which may include counters that are not enabled yet. 506 */ 507 sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_STOP, 508 0, pmu->cmask, 0, 0, 0, 0); 509 } 510 511 static inline void pmu_sbi_stop_hw_ctrs(struct riscv_pmu *pmu) 512 { 513 struct cpu_hw_events *cpu_hw_evt = this_cpu_ptr(pmu->hw_events); 514 515 /* No need to check the error here as we can't do anything about the error */ 516 sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_STOP, 0, 517 cpu_hw_evt->used_hw_ctrs[0], 0, 0, 0, 0); 518 } 519 520 /* 521 * This function starts all the used counters in two step approach. 522 * Any counter that did not overflow can be start in a single step 523 * while the overflowed counters need to be started with updated initialization 524 * value. 525 */ 526 static inline void pmu_sbi_start_overflow_mask(struct riscv_pmu *pmu, 527 unsigned long ctr_ovf_mask) 528 { 529 int idx = 0; 530 struct cpu_hw_events *cpu_hw_evt = this_cpu_ptr(pmu->hw_events); 531 struct perf_event *event; 532 unsigned long flag = SBI_PMU_START_FLAG_SET_INIT_VALUE; 533 unsigned long ctr_start_mask = 0; 534 uint64_t max_period; 535 struct hw_perf_event *hwc; 536 u64 init_val = 0; 537 538 ctr_start_mask = cpu_hw_evt->used_hw_ctrs[0] & ~ctr_ovf_mask; 539 540 /* Start all the counters that did not overflow in a single shot */ 541 sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, 0, ctr_start_mask, 542 0, 0, 0, 0); 543 544 /* Reinitialize and start all the counter that overflowed */ 545 while (ctr_ovf_mask) { 546 if (ctr_ovf_mask & 0x01) { 547 event = cpu_hw_evt->events[idx]; 548 hwc = &event->hw; 549 max_period = riscv_pmu_ctr_get_width_mask(event); 550 init_val = local64_read(&hwc->prev_count) & max_period; 551 #if defined(CONFIG_32BIT) 552 sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, idx, 1, 553 flag, init_val, init_val >> 32, 0); 554 #else 555 sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, idx, 1, 556 flag, init_val, 0, 0); 557 #endif 558 perf_event_update_userpage(event); 559 } 560 ctr_ovf_mask = ctr_ovf_mask >> 1; 561 idx++; 562 } 563 } 564 565 static irqreturn_t pmu_sbi_ovf_handler(int irq, void *dev) 566 { 567 struct perf_sample_data data; 568 struct pt_regs *regs; 569 struct hw_perf_event *hw_evt; 570 union sbi_pmu_ctr_info *info; 571 int lidx, hidx, fidx; 572 struct riscv_pmu *pmu; 573 struct perf_event *event; 574 unsigned long overflow; 575 unsigned long overflowed_ctrs = 0; 576 struct cpu_hw_events *cpu_hw_evt = dev; 577 u64 start_clock = sched_clock(); 578 579 if (WARN_ON_ONCE(!cpu_hw_evt)) 580 return IRQ_NONE; 581 582 /* Firmware counter don't support overflow yet */ 583 fidx = find_first_bit(cpu_hw_evt->used_hw_ctrs, RISCV_MAX_COUNTERS); 584 event = cpu_hw_evt->events[fidx]; 585 if (!event) { 586 csr_clear(CSR_SIP, BIT(riscv_pmu_irq_num)); 587 return IRQ_NONE; 588 } 589 590 pmu = to_riscv_pmu(event->pmu); 591 pmu_sbi_stop_hw_ctrs(pmu); 592 593 /* Overflow status register should only be read after counter are stopped */ 594 ALT_SBI_PMU_OVERFLOW(overflow); 595 596 /* 597 * Overflow interrupt pending bit should only be cleared after stopping 598 * all the counters to avoid any race condition. 599 */ 600 csr_clear(CSR_SIP, BIT(riscv_pmu_irq_num)); 601 602 /* No overflow bit is set */ 603 if (!overflow) 604 return IRQ_NONE; 605 606 regs = get_irq_regs(); 607 608 for_each_set_bit(lidx, cpu_hw_evt->used_hw_ctrs, RISCV_MAX_COUNTERS) { 609 struct perf_event *event = cpu_hw_evt->events[lidx]; 610 611 /* Skip if invalid event or user did not request a sampling */ 612 if (!event || !is_sampling_event(event)) 613 continue; 614 615 info = &pmu_ctr_list[lidx]; 616 /* Do a sanity check */ 617 if (!info || info->type != SBI_PMU_CTR_TYPE_HW) 618 continue; 619 620 /* compute hardware counter index */ 621 hidx = info->csr - CSR_CYCLE; 622 /* check if the corresponding bit is set in sscountovf */ 623 if (!(overflow & (1 << hidx))) 624 continue; 625 626 /* 627 * Keep a track of overflowed counters so that they can be started 628 * with updated initial value. 629 */ 630 overflowed_ctrs |= 1 << lidx; 631 hw_evt = &event->hw; 632 riscv_pmu_event_update(event); 633 perf_sample_data_init(&data, 0, hw_evt->last_period); 634 if (riscv_pmu_event_set_period(event)) { 635 /* 636 * Unlike other ISAs, RISC-V don't have to disable interrupts 637 * to avoid throttling here. As per the specification, the 638 * interrupt remains disabled until the OF bit is set. 639 * Interrupts are enabled again only during the start. 640 * TODO: We will need to stop the guest counters once 641 * virtualization support is added. 642 */ 643 perf_event_overflow(event, &data, regs); 644 } 645 } 646 647 pmu_sbi_start_overflow_mask(pmu, overflowed_ctrs); 648 perf_sample_event_took(sched_clock() - start_clock); 649 650 return IRQ_HANDLED; 651 } 652 653 static int pmu_sbi_starting_cpu(unsigned int cpu, struct hlist_node *node) 654 { 655 struct riscv_pmu *pmu = hlist_entry_safe(node, struct riscv_pmu, node); 656 struct cpu_hw_events *cpu_hw_evt = this_cpu_ptr(pmu->hw_events); 657 658 /* 659 * Enable the access for CYCLE, TIME, and INSTRET CSRs from userspace, 660 * as is necessary to maintain uABI compatibility. 661 */ 662 csr_write(CSR_SCOUNTEREN, 0x7); 663 664 /* Stop all the counters so that they can be enabled from perf */ 665 pmu_sbi_stop_all(pmu); 666 667 if (riscv_pmu_use_irq) { 668 cpu_hw_evt->irq = riscv_pmu_irq; 669 csr_clear(CSR_IP, BIT(riscv_pmu_irq_num)); 670 csr_set(CSR_IE, BIT(riscv_pmu_irq_num)); 671 enable_percpu_irq(riscv_pmu_irq, IRQ_TYPE_NONE); 672 } 673 674 return 0; 675 } 676 677 static int pmu_sbi_dying_cpu(unsigned int cpu, struct hlist_node *node) 678 { 679 if (riscv_pmu_use_irq) { 680 disable_percpu_irq(riscv_pmu_irq); 681 csr_clear(CSR_IE, BIT(riscv_pmu_irq_num)); 682 } 683 684 /* Disable all counters access for user mode now */ 685 csr_write(CSR_SCOUNTEREN, 0x0); 686 687 return 0; 688 } 689 690 static int pmu_sbi_setup_irqs(struct riscv_pmu *pmu, struct platform_device *pdev) 691 { 692 int ret; 693 struct cpu_hw_events __percpu *hw_events = pmu->hw_events; 694 struct device_node *cpu, *child; 695 struct irq_domain *domain = NULL; 696 697 if (riscv_isa_extension_available(NULL, SSCOFPMF)) { 698 riscv_pmu_irq_num = RV_IRQ_PMU; 699 riscv_pmu_use_irq = true; 700 } else if (IS_ENABLED(CONFIG_ERRATA_THEAD_PMU) && 701 riscv_cached_mvendorid(0) == THEAD_VENDOR_ID && 702 riscv_cached_marchid(0) == 0 && 703 riscv_cached_mimpid(0) == 0) { 704 riscv_pmu_irq_num = THEAD_C9XX_RV_IRQ_PMU; 705 riscv_pmu_use_irq = true; 706 } 707 708 if (!riscv_pmu_use_irq) 709 return -EOPNOTSUPP; 710 711 for_each_of_cpu_node(cpu) { 712 child = of_get_compatible_child(cpu, "riscv,cpu-intc"); 713 if (!child) { 714 pr_err("Failed to find INTC node\n"); 715 of_node_put(cpu); 716 return -ENODEV; 717 } 718 domain = irq_find_host(child); 719 of_node_put(child); 720 if (domain) { 721 of_node_put(cpu); 722 break; 723 } 724 } 725 if (!domain) { 726 pr_err("Failed to find INTC IRQ root domain\n"); 727 return -ENODEV; 728 } 729 730 riscv_pmu_irq = irq_create_mapping(domain, riscv_pmu_irq_num); 731 if (!riscv_pmu_irq) { 732 pr_err("Failed to map PMU interrupt for node\n"); 733 return -ENODEV; 734 } 735 736 ret = request_percpu_irq(riscv_pmu_irq, pmu_sbi_ovf_handler, "riscv-pmu", hw_events); 737 if (ret) { 738 pr_err("registering percpu irq failed [%d]\n", ret); 739 return ret; 740 } 741 742 return 0; 743 } 744 745 #ifdef CONFIG_CPU_PM 746 static int riscv_pm_pmu_notify(struct notifier_block *b, unsigned long cmd, 747 void *v) 748 { 749 struct riscv_pmu *rvpmu = container_of(b, struct riscv_pmu, riscv_pm_nb); 750 struct cpu_hw_events *cpuc = this_cpu_ptr(rvpmu->hw_events); 751 int enabled = bitmap_weight(cpuc->used_hw_ctrs, RISCV_MAX_COUNTERS); 752 struct perf_event *event; 753 int idx; 754 755 if (!enabled) 756 return NOTIFY_OK; 757 758 for (idx = 0; idx < RISCV_MAX_COUNTERS; idx++) { 759 event = cpuc->events[idx]; 760 if (!event) 761 continue; 762 763 switch (cmd) { 764 case CPU_PM_ENTER: 765 /* 766 * Stop and update the counter 767 */ 768 riscv_pmu_stop(event, PERF_EF_UPDATE); 769 break; 770 case CPU_PM_EXIT: 771 case CPU_PM_ENTER_FAILED: 772 /* 773 * Restore and enable the counter. 774 * 775 * Requires RCU read locking to be functional, 776 * wrap the call within RCU_NONIDLE to make the 777 * RCU subsystem aware this cpu is not idle from 778 * an RCU perspective for the riscv_pmu_start() call 779 * duration. 780 */ 781 RCU_NONIDLE(riscv_pmu_start(event, PERF_EF_RELOAD)); 782 break; 783 default: 784 break; 785 } 786 } 787 788 return NOTIFY_OK; 789 } 790 791 static int riscv_pm_pmu_register(struct riscv_pmu *pmu) 792 { 793 pmu->riscv_pm_nb.notifier_call = riscv_pm_pmu_notify; 794 return cpu_pm_register_notifier(&pmu->riscv_pm_nb); 795 } 796 797 static void riscv_pm_pmu_unregister(struct riscv_pmu *pmu) 798 { 799 cpu_pm_unregister_notifier(&pmu->riscv_pm_nb); 800 } 801 #else 802 static inline int riscv_pm_pmu_register(struct riscv_pmu *pmu) { return 0; } 803 static inline void riscv_pm_pmu_unregister(struct riscv_pmu *pmu) { } 804 #endif 805 806 static void riscv_pmu_destroy(struct riscv_pmu *pmu) 807 { 808 riscv_pm_pmu_unregister(pmu); 809 cpuhp_state_remove_instance(CPUHP_AP_PERF_RISCV_STARTING, &pmu->node); 810 } 811 812 static int pmu_sbi_device_probe(struct platform_device *pdev) 813 { 814 struct riscv_pmu *pmu = NULL; 815 unsigned long cmask = 0; 816 int ret = -ENODEV; 817 int num_counters; 818 819 pr_info("SBI PMU extension is available\n"); 820 pmu = riscv_pmu_alloc(); 821 if (!pmu) 822 return -ENOMEM; 823 824 num_counters = pmu_sbi_find_num_ctrs(); 825 if (num_counters < 0) { 826 pr_err("SBI PMU extension doesn't provide any counters\n"); 827 goto out_free; 828 } 829 830 /* cache all the information about counters now */ 831 if (pmu_sbi_get_ctrinfo(num_counters, &cmask)) 832 goto out_free; 833 834 ret = pmu_sbi_setup_irqs(pmu, pdev); 835 if (ret < 0) { 836 pr_info("Perf sampling/filtering is not supported as sscof extension is not available\n"); 837 pmu->pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT; 838 pmu->pmu.capabilities |= PERF_PMU_CAP_NO_EXCLUDE; 839 } 840 841 pmu->pmu.attr_groups = riscv_pmu_attr_groups; 842 pmu->cmask = cmask; 843 pmu->ctr_start = pmu_sbi_ctr_start; 844 pmu->ctr_stop = pmu_sbi_ctr_stop; 845 pmu->event_map = pmu_sbi_event_map; 846 pmu->ctr_get_idx = pmu_sbi_ctr_get_idx; 847 pmu->ctr_get_width = pmu_sbi_ctr_get_width; 848 pmu->ctr_clear_idx = pmu_sbi_ctr_clear_idx; 849 pmu->ctr_read = pmu_sbi_ctr_read; 850 851 ret = cpuhp_state_add_instance(CPUHP_AP_PERF_RISCV_STARTING, &pmu->node); 852 if (ret) 853 return ret; 854 855 ret = riscv_pm_pmu_register(pmu); 856 if (ret) 857 goto out_unregister; 858 859 ret = perf_pmu_register(&pmu->pmu, "cpu", PERF_TYPE_RAW); 860 if (ret) 861 goto out_unregister; 862 863 return 0; 864 865 out_unregister: 866 riscv_pmu_destroy(pmu); 867 868 out_free: 869 kfree(pmu); 870 return ret; 871 } 872 873 static struct platform_driver pmu_sbi_driver = { 874 .probe = pmu_sbi_device_probe, 875 .driver = { 876 .name = RISCV_PMU_PDEV_NAME, 877 }, 878 }; 879 880 static int __init pmu_sbi_devinit(void) 881 { 882 int ret; 883 struct platform_device *pdev; 884 885 if (sbi_spec_version < sbi_mk_version(0, 3) || 886 sbi_probe_extension(SBI_EXT_PMU) <= 0) { 887 return 0; 888 } 889 890 ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_RISCV_STARTING, 891 "perf/riscv/pmu:starting", 892 pmu_sbi_starting_cpu, pmu_sbi_dying_cpu); 893 if (ret) { 894 pr_err("CPU hotplug notifier could not be registered: %d\n", 895 ret); 896 return ret; 897 } 898 899 ret = platform_driver_register(&pmu_sbi_driver); 900 if (ret) 901 return ret; 902 903 pdev = platform_device_register_simple(RISCV_PMU_PDEV_NAME, -1, NULL, 0); 904 if (IS_ERR(pdev)) { 905 platform_driver_unregister(&pmu_sbi_driver); 906 return PTR_ERR(pdev); 907 } 908 909 /* Notify legacy implementation that SBI pmu is available*/ 910 riscv_pmu_legacy_skip_init(); 911 912 return ret; 913 } 914 device_initcall(pmu_sbi_devinit) 915