1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * amd-pstate.c - AMD Processor P-state Frequency Driver 4 * 5 * Copyright (C) 2021 Advanced Micro Devices, Inc. All Rights Reserved. 6 * 7 * Author: Huang Rui <ray.huang@amd.com> 8 * 9 * AMD P-State introduces a new CPU performance scaling design for AMD 10 * processors using the ACPI Collaborative Performance and Power Control (CPPC) 11 * feature which works with the AMD SMU firmware providing a finer grained 12 * frequency control range. It is to replace the legacy ACPI P-States control, 13 * allows a flexible, low-latency interface for the Linux kernel to directly 14 * communicate the performance hints to hardware. 15 * 16 * AMD P-State is supported on recent AMD Zen base CPU series include some of 17 * Zen2 and Zen3 processors. _CPC needs to be present in the ACPI tables of AMD 18 * P-State supported system. And there are two types of hardware implementations 19 * for AMD P-State: 1) Full MSR Solution and 2) Shared Memory Solution. 20 * X86_FEATURE_CPPC CPU feature flag is used to distinguish the different types. 21 */ 22 23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 24 25 #include <linux/kernel.h> 26 #include <linux/module.h> 27 #include <linux/init.h> 28 #include <linux/smp.h> 29 #include <linux/sched.h> 30 #include <linux/cpufreq.h> 31 #include <linux/compiler.h> 32 #include <linux/dmi.h> 33 #include <linux/slab.h> 34 #include <linux/acpi.h> 35 #include <linux/io.h> 36 #include <linux/delay.h> 37 #include <linux/uaccess.h> 38 #include <linux/static_call.h> 39 #include <linux/amd-pstate.h> 40 41 #include <acpi/processor.h> 42 #include <acpi/cppc_acpi.h> 43 44 #include <asm/msr.h> 45 #include <asm/processor.h> 46 #include <asm/cpufeature.h> 47 #include <asm/cpu_device_id.h> 48 #include "amd-pstate-trace.h" 49 50 #define AMD_PSTATE_TRANSITION_LATENCY 20000 51 #define AMD_PSTATE_TRANSITION_DELAY 1000 52 53 /* 54 * TODO: We need more time to fine tune processors with shared memory solution 55 * with community together. 56 * 57 * There are some performance drops on the CPU benchmarks which reports from 58 * Suse. We are co-working with them to fine tune the shared memory solution. So 59 * we disable it by default to go acpi-cpufreq on these processors and add a 60 * module parameter to be able to enable it manually for debugging. 61 */ 62 static struct cpufreq_driver *current_pstate_driver; 63 static struct cpufreq_driver amd_pstate_driver; 64 static struct cpufreq_driver amd_pstate_epp_driver; 65 static int cppc_state = AMD_PSTATE_UNDEFINED; 66 static bool cppc_enabled; 67 68 /* 69 * AMD Energy Preference Performance (EPP) 70 * The EPP is used in the CCLK DPM controller to drive 71 * the frequency that a core is going to operate during 72 * short periods of activity. EPP values will be utilized for 73 * different OS profiles (balanced, performance, power savings) 74 * display strings corresponding to EPP index in the 75 * energy_perf_strings[] 76 * index String 77 *------------------------------------- 78 * 0 default 79 * 1 performance 80 * 2 balance_performance 81 * 3 balance_power 82 * 4 power 83 */ 84 enum energy_perf_value_index { 85 EPP_INDEX_DEFAULT = 0, 86 EPP_INDEX_PERFORMANCE, 87 EPP_INDEX_BALANCE_PERFORMANCE, 88 EPP_INDEX_BALANCE_POWERSAVE, 89 EPP_INDEX_POWERSAVE, 90 }; 91 92 static const char * const energy_perf_strings[] = { 93 [EPP_INDEX_DEFAULT] = "default", 94 [EPP_INDEX_PERFORMANCE] = "performance", 95 [EPP_INDEX_BALANCE_PERFORMANCE] = "balance_performance", 96 [EPP_INDEX_BALANCE_POWERSAVE] = "balance_power", 97 [EPP_INDEX_POWERSAVE] = "power", 98 NULL 99 }; 100 101 static unsigned int epp_values[] = { 102 [EPP_INDEX_DEFAULT] = 0, 103 [EPP_INDEX_PERFORMANCE] = AMD_CPPC_EPP_PERFORMANCE, 104 [EPP_INDEX_BALANCE_PERFORMANCE] = AMD_CPPC_EPP_BALANCE_PERFORMANCE, 105 [EPP_INDEX_BALANCE_POWERSAVE] = AMD_CPPC_EPP_BALANCE_POWERSAVE, 106 [EPP_INDEX_POWERSAVE] = AMD_CPPC_EPP_POWERSAVE, 107 }; 108 109 typedef int (*cppc_mode_transition_fn)(int); 110 111 static inline int get_mode_idx_from_str(const char *str, size_t size) 112 { 113 int i; 114 115 for (i=0; i < AMD_PSTATE_MAX; i++) { 116 if (!strncmp(str, amd_pstate_mode_string[i], size)) 117 return i; 118 } 119 return -EINVAL; 120 } 121 122 static DEFINE_MUTEX(amd_pstate_limits_lock); 123 static DEFINE_MUTEX(amd_pstate_driver_lock); 124 125 static s16 amd_pstate_get_epp(struct amd_cpudata *cpudata, u64 cppc_req_cached) 126 { 127 u64 epp; 128 int ret; 129 130 if (boot_cpu_has(X86_FEATURE_CPPC)) { 131 if (!cppc_req_cached) { 132 epp = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, 133 &cppc_req_cached); 134 if (epp) 135 return epp; 136 } 137 epp = (cppc_req_cached >> 24) & 0xFF; 138 } else { 139 ret = cppc_get_epp_perf(cpudata->cpu, &epp); 140 if (ret < 0) { 141 pr_debug("Could not retrieve energy perf value (%d)\n", ret); 142 return -EIO; 143 } 144 } 145 146 return (s16)(epp & 0xff); 147 } 148 149 static int amd_pstate_get_energy_pref_index(struct amd_cpudata *cpudata) 150 { 151 s16 epp; 152 int index = -EINVAL; 153 154 epp = amd_pstate_get_epp(cpudata, 0); 155 if (epp < 0) 156 return epp; 157 158 switch (epp) { 159 case AMD_CPPC_EPP_PERFORMANCE: 160 index = EPP_INDEX_PERFORMANCE; 161 break; 162 case AMD_CPPC_EPP_BALANCE_PERFORMANCE: 163 index = EPP_INDEX_BALANCE_PERFORMANCE; 164 break; 165 case AMD_CPPC_EPP_BALANCE_POWERSAVE: 166 index = EPP_INDEX_BALANCE_POWERSAVE; 167 break; 168 case AMD_CPPC_EPP_POWERSAVE: 169 index = EPP_INDEX_POWERSAVE; 170 break; 171 default: 172 break; 173 } 174 175 return index; 176 } 177 178 static int amd_pstate_set_epp(struct amd_cpudata *cpudata, u32 epp) 179 { 180 int ret; 181 struct cppc_perf_ctrls perf_ctrls; 182 183 if (boot_cpu_has(X86_FEATURE_CPPC)) { 184 u64 value = READ_ONCE(cpudata->cppc_req_cached); 185 186 value &= ~GENMASK_ULL(31, 24); 187 value |= (u64)epp << 24; 188 WRITE_ONCE(cpudata->cppc_req_cached, value); 189 190 ret = wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value); 191 if (!ret) 192 cpudata->epp_cached = epp; 193 } else { 194 perf_ctrls.energy_perf = epp; 195 ret = cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1); 196 if (ret) { 197 pr_debug("failed to set energy perf value (%d)\n", ret); 198 return ret; 199 } 200 cpudata->epp_cached = epp; 201 } 202 203 return ret; 204 } 205 206 static int amd_pstate_set_energy_pref_index(struct amd_cpudata *cpudata, 207 int pref_index) 208 { 209 int epp = -EINVAL; 210 int ret; 211 212 if (!pref_index) { 213 pr_debug("EPP pref_index is invalid\n"); 214 return -EINVAL; 215 } 216 217 if (epp == -EINVAL) 218 epp = epp_values[pref_index]; 219 220 if (epp > 0 && cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) { 221 pr_debug("EPP cannot be set under performance policy\n"); 222 return -EBUSY; 223 } 224 225 ret = amd_pstate_set_epp(cpudata, epp); 226 227 return ret; 228 } 229 230 static inline int pstate_enable(bool enable) 231 { 232 int ret, cpu; 233 unsigned long logical_proc_id_mask = 0; 234 235 if (enable == cppc_enabled) 236 return 0; 237 238 for_each_present_cpu(cpu) { 239 unsigned long logical_id = topology_logical_die_id(cpu); 240 241 if (test_bit(logical_id, &logical_proc_id_mask)) 242 continue; 243 244 set_bit(logical_id, &logical_proc_id_mask); 245 246 ret = wrmsrl_safe_on_cpu(cpu, MSR_AMD_CPPC_ENABLE, 247 enable); 248 if (ret) 249 return ret; 250 } 251 252 cppc_enabled = enable; 253 return 0; 254 } 255 256 static int cppc_enable(bool enable) 257 { 258 int cpu, ret = 0; 259 struct cppc_perf_ctrls perf_ctrls; 260 261 if (enable == cppc_enabled) 262 return 0; 263 264 for_each_present_cpu(cpu) { 265 ret = cppc_set_enable(cpu, enable); 266 if (ret) 267 return ret; 268 269 /* Enable autonomous mode for EPP */ 270 if (cppc_state == AMD_PSTATE_ACTIVE) { 271 /* Set desired perf as zero to allow EPP firmware control */ 272 perf_ctrls.desired_perf = 0; 273 ret = cppc_set_perf(cpu, &perf_ctrls); 274 if (ret) 275 return ret; 276 } 277 } 278 279 cppc_enabled = enable; 280 return ret; 281 } 282 283 DEFINE_STATIC_CALL(amd_pstate_enable, pstate_enable); 284 285 static inline int amd_pstate_enable(bool enable) 286 { 287 return static_call(amd_pstate_enable)(enable); 288 } 289 290 static int pstate_init_perf(struct amd_cpudata *cpudata) 291 { 292 u64 cap1; 293 u32 highest_perf; 294 295 int ret = rdmsrl_safe_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1, 296 &cap1); 297 if (ret) 298 return ret; 299 300 /* 301 * TODO: Introduce AMD specific power feature. 302 * 303 * CPPC entry doesn't indicate the highest performance in some ASICs. 304 */ 305 highest_perf = amd_get_highest_perf(); 306 if (highest_perf > AMD_CPPC_HIGHEST_PERF(cap1)) 307 highest_perf = AMD_CPPC_HIGHEST_PERF(cap1); 308 309 WRITE_ONCE(cpudata->highest_perf, highest_perf); 310 WRITE_ONCE(cpudata->max_limit_perf, highest_perf); 311 WRITE_ONCE(cpudata->nominal_perf, AMD_CPPC_NOMINAL_PERF(cap1)); 312 WRITE_ONCE(cpudata->lowest_nonlinear_perf, AMD_CPPC_LOWNONLIN_PERF(cap1)); 313 WRITE_ONCE(cpudata->lowest_perf, AMD_CPPC_LOWEST_PERF(cap1)); 314 WRITE_ONCE(cpudata->min_limit_perf, AMD_CPPC_LOWEST_PERF(cap1)); 315 return 0; 316 } 317 318 static int cppc_init_perf(struct amd_cpudata *cpudata) 319 { 320 struct cppc_perf_caps cppc_perf; 321 u32 highest_perf; 322 323 int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); 324 if (ret) 325 return ret; 326 327 highest_perf = amd_get_highest_perf(); 328 if (highest_perf > cppc_perf.highest_perf) 329 highest_perf = cppc_perf.highest_perf; 330 331 WRITE_ONCE(cpudata->highest_perf, highest_perf); 332 WRITE_ONCE(cpudata->max_limit_perf, highest_perf); 333 WRITE_ONCE(cpudata->nominal_perf, cppc_perf.nominal_perf); 334 WRITE_ONCE(cpudata->lowest_nonlinear_perf, 335 cppc_perf.lowest_nonlinear_perf); 336 WRITE_ONCE(cpudata->lowest_perf, cppc_perf.lowest_perf); 337 WRITE_ONCE(cpudata->min_limit_perf, cppc_perf.lowest_perf); 338 339 if (cppc_state == AMD_PSTATE_ACTIVE) 340 return 0; 341 342 ret = cppc_get_auto_sel_caps(cpudata->cpu, &cppc_perf); 343 if (ret) { 344 pr_warn("failed to get auto_sel, ret: %d\n", ret); 345 return 0; 346 } 347 348 ret = cppc_set_auto_sel(cpudata->cpu, 349 (cppc_state == AMD_PSTATE_PASSIVE) ? 0 : 1); 350 351 if (ret) 352 pr_warn("failed to set auto_sel, ret: %d\n", ret); 353 354 return ret; 355 } 356 357 DEFINE_STATIC_CALL(amd_pstate_init_perf, pstate_init_perf); 358 359 static inline int amd_pstate_init_perf(struct amd_cpudata *cpudata) 360 { 361 return static_call(amd_pstate_init_perf)(cpudata); 362 } 363 364 static void pstate_update_perf(struct amd_cpudata *cpudata, u32 min_perf, 365 u32 des_perf, u32 max_perf, bool fast_switch) 366 { 367 if (fast_switch) 368 wrmsrl(MSR_AMD_CPPC_REQ, READ_ONCE(cpudata->cppc_req_cached)); 369 else 370 wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, 371 READ_ONCE(cpudata->cppc_req_cached)); 372 } 373 374 static void cppc_update_perf(struct amd_cpudata *cpudata, 375 u32 min_perf, u32 des_perf, 376 u32 max_perf, bool fast_switch) 377 { 378 struct cppc_perf_ctrls perf_ctrls; 379 380 perf_ctrls.max_perf = max_perf; 381 perf_ctrls.min_perf = min_perf; 382 perf_ctrls.desired_perf = des_perf; 383 384 cppc_set_perf(cpudata->cpu, &perf_ctrls); 385 } 386 387 DEFINE_STATIC_CALL(amd_pstate_update_perf, pstate_update_perf); 388 389 static inline void amd_pstate_update_perf(struct amd_cpudata *cpudata, 390 u32 min_perf, u32 des_perf, 391 u32 max_perf, bool fast_switch) 392 { 393 static_call(amd_pstate_update_perf)(cpudata, min_perf, des_perf, 394 max_perf, fast_switch); 395 } 396 397 static inline bool amd_pstate_sample(struct amd_cpudata *cpudata) 398 { 399 u64 aperf, mperf, tsc; 400 unsigned long flags; 401 402 local_irq_save(flags); 403 rdmsrl(MSR_IA32_APERF, aperf); 404 rdmsrl(MSR_IA32_MPERF, mperf); 405 tsc = rdtsc(); 406 407 if (cpudata->prev.mperf == mperf || cpudata->prev.tsc == tsc) { 408 local_irq_restore(flags); 409 return false; 410 } 411 412 local_irq_restore(flags); 413 414 cpudata->cur.aperf = aperf; 415 cpudata->cur.mperf = mperf; 416 cpudata->cur.tsc = tsc; 417 cpudata->cur.aperf -= cpudata->prev.aperf; 418 cpudata->cur.mperf -= cpudata->prev.mperf; 419 cpudata->cur.tsc -= cpudata->prev.tsc; 420 421 cpudata->prev.aperf = aperf; 422 cpudata->prev.mperf = mperf; 423 cpudata->prev.tsc = tsc; 424 425 cpudata->freq = div64_u64((cpudata->cur.aperf * cpu_khz), cpudata->cur.mperf); 426 427 return true; 428 } 429 430 static void amd_pstate_update(struct amd_cpudata *cpudata, u32 min_perf, 431 u32 des_perf, u32 max_perf, bool fast_switch, int gov_flags) 432 { 433 u64 prev = READ_ONCE(cpudata->cppc_req_cached); 434 u64 value = prev; 435 436 min_perf = clamp_t(unsigned long, min_perf, cpudata->min_limit_perf, 437 cpudata->max_limit_perf); 438 max_perf = clamp_t(unsigned long, max_perf, cpudata->min_limit_perf, 439 cpudata->max_limit_perf); 440 des_perf = clamp_t(unsigned long, des_perf, min_perf, max_perf); 441 442 if ((cppc_state == AMD_PSTATE_GUIDED) && (gov_flags & CPUFREQ_GOV_DYNAMIC_SWITCHING)) { 443 min_perf = des_perf; 444 des_perf = 0; 445 } 446 447 value &= ~AMD_CPPC_MIN_PERF(~0L); 448 value |= AMD_CPPC_MIN_PERF(min_perf); 449 450 value &= ~AMD_CPPC_DES_PERF(~0L); 451 value |= AMD_CPPC_DES_PERF(des_perf); 452 453 value &= ~AMD_CPPC_MAX_PERF(~0L); 454 value |= AMD_CPPC_MAX_PERF(max_perf); 455 456 if (trace_amd_pstate_perf_enabled() && amd_pstate_sample(cpudata)) { 457 trace_amd_pstate_perf(min_perf, des_perf, max_perf, cpudata->freq, 458 cpudata->cur.mperf, cpudata->cur.aperf, cpudata->cur.tsc, 459 cpudata->cpu, (value != prev), fast_switch); 460 } 461 462 if (value == prev) 463 return; 464 465 WRITE_ONCE(cpudata->cppc_req_cached, value); 466 467 amd_pstate_update_perf(cpudata, min_perf, des_perf, 468 max_perf, fast_switch); 469 } 470 471 static int amd_pstate_verify(struct cpufreq_policy_data *policy) 472 { 473 cpufreq_verify_within_cpu_limits(policy); 474 475 return 0; 476 } 477 478 static int amd_pstate_update_min_max_limit(struct cpufreq_policy *policy) 479 { 480 u32 max_limit_perf, min_limit_perf; 481 struct amd_cpudata *cpudata = policy->driver_data; 482 483 max_limit_perf = div_u64(policy->max * cpudata->highest_perf, cpudata->max_freq); 484 min_limit_perf = div_u64(policy->min * cpudata->highest_perf, cpudata->max_freq); 485 486 WRITE_ONCE(cpudata->max_limit_perf, max_limit_perf); 487 WRITE_ONCE(cpudata->min_limit_perf, min_limit_perf); 488 WRITE_ONCE(cpudata->max_limit_freq, policy->max); 489 WRITE_ONCE(cpudata->min_limit_freq, policy->min); 490 491 return 0; 492 } 493 494 static int amd_pstate_update_freq(struct cpufreq_policy *policy, 495 unsigned int target_freq, bool fast_switch) 496 { 497 struct cpufreq_freqs freqs; 498 struct amd_cpudata *cpudata = policy->driver_data; 499 unsigned long max_perf, min_perf, des_perf, cap_perf; 500 501 if (!cpudata->max_freq) 502 return -ENODEV; 503 504 if (policy->min != cpudata->min_limit_freq || policy->max != cpudata->max_limit_freq) 505 amd_pstate_update_min_max_limit(policy); 506 507 cap_perf = READ_ONCE(cpudata->highest_perf); 508 min_perf = READ_ONCE(cpudata->lowest_perf); 509 max_perf = cap_perf; 510 511 freqs.old = policy->cur; 512 freqs.new = target_freq; 513 514 des_perf = DIV_ROUND_CLOSEST(target_freq * cap_perf, 515 cpudata->max_freq); 516 517 WARN_ON(fast_switch && !policy->fast_switch_enabled); 518 /* 519 * If fast_switch is desired, then there aren't any registered 520 * transition notifiers. See comment for 521 * cpufreq_enable_fast_switch(). 522 */ 523 if (!fast_switch) 524 cpufreq_freq_transition_begin(policy, &freqs); 525 526 amd_pstate_update(cpudata, min_perf, des_perf, 527 max_perf, fast_switch, policy->governor->flags); 528 529 if (!fast_switch) 530 cpufreq_freq_transition_end(policy, &freqs, false); 531 532 return 0; 533 } 534 535 static int amd_pstate_target(struct cpufreq_policy *policy, 536 unsigned int target_freq, 537 unsigned int relation) 538 { 539 return amd_pstate_update_freq(policy, target_freq, false); 540 } 541 542 static unsigned int amd_pstate_fast_switch(struct cpufreq_policy *policy, 543 unsigned int target_freq) 544 { 545 if (!amd_pstate_update_freq(policy, target_freq, true)) 546 return target_freq; 547 return policy->cur; 548 } 549 550 static void amd_pstate_adjust_perf(unsigned int cpu, 551 unsigned long _min_perf, 552 unsigned long target_perf, 553 unsigned long capacity) 554 { 555 unsigned long max_perf, min_perf, des_perf, 556 cap_perf, lowest_nonlinear_perf, max_freq; 557 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); 558 struct amd_cpudata *cpudata = policy->driver_data; 559 unsigned int target_freq; 560 561 if (policy->min != cpudata->min_limit_freq || policy->max != cpudata->max_limit_freq) 562 amd_pstate_update_min_max_limit(policy); 563 564 565 cap_perf = READ_ONCE(cpudata->highest_perf); 566 lowest_nonlinear_perf = READ_ONCE(cpudata->lowest_nonlinear_perf); 567 max_freq = READ_ONCE(cpudata->max_freq); 568 569 des_perf = cap_perf; 570 if (target_perf < capacity) 571 des_perf = DIV_ROUND_UP(cap_perf * target_perf, capacity); 572 573 min_perf = READ_ONCE(cpudata->lowest_perf); 574 if (_min_perf < capacity) 575 min_perf = DIV_ROUND_UP(cap_perf * _min_perf, capacity); 576 577 if (min_perf < lowest_nonlinear_perf) 578 min_perf = lowest_nonlinear_perf; 579 580 max_perf = cap_perf; 581 if (max_perf < min_perf) 582 max_perf = min_perf; 583 584 des_perf = clamp_t(unsigned long, des_perf, min_perf, max_perf); 585 target_freq = div_u64(des_perf * max_freq, max_perf); 586 policy->cur = target_freq; 587 588 amd_pstate_update(cpudata, min_perf, des_perf, max_perf, true, 589 policy->governor->flags); 590 cpufreq_cpu_put(policy); 591 } 592 593 static int amd_get_min_freq(struct amd_cpudata *cpudata) 594 { 595 struct cppc_perf_caps cppc_perf; 596 597 int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); 598 if (ret) 599 return ret; 600 601 /* Switch to khz */ 602 return cppc_perf.lowest_freq * 1000; 603 } 604 605 static int amd_get_max_freq(struct amd_cpudata *cpudata) 606 { 607 struct cppc_perf_caps cppc_perf; 608 u32 max_perf, max_freq, nominal_freq, nominal_perf; 609 u64 boost_ratio; 610 611 int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); 612 if (ret) 613 return ret; 614 615 nominal_freq = cppc_perf.nominal_freq; 616 nominal_perf = READ_ONCE(cpudata->nominal_perf); 617 max_perf = READ_ONCE(cpudata->highest_perf); 618 619 boost_ratio = div_u64(max_perf << SCHED_CAPACITY_SHIFT, 620 nominal_perf); 621 622 max_freq = nominal_freq * boost_ratio >> SCHED_CAPACITY_SHIFT; 623 624 /* Switch to khz */ 625 return max_freq * 1000; 626 } 627 628 static int amd_get_nominal_freq(struct amd_cpudata *cpudata) 629 { 630 struct cppc_perf_caps cppc_perf; 631 632 int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); 633 if (ret) 634 return ret; 635 636 /* Switch to khz */ 637 return cppc_perf.nominal_freq * 1000; 638 } 639 640 static int amd_get_lowest_nonlinear_freq(struct amd_cpudata *cpudata) 641 { 642 struct cppc_perf_caps cppc_perf; 643 u32 lowest_nonlinear_freq, lowest_nonlinear_perf, 644 nominal_freq, nominal_perf; 645 u64 lowest_nonlinear_ratio; 646 647 int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); 648 if (ret) 649 return ret; 650 651 nominal_freq = cppc_perf.nominal_freq; 652 nominal_perf = READ_ONCE(cpudata->nominal_perf); 653 654 lowest_nonlinear_perf = cppc_perf.lowest_nonlinear_perf; 655 656 lowest_nonlinear_ratio = div_u64(lowest_nonlinear_perf << SCHED_CAPACITY_SHIFT, 657 nominal_perf); 658 659 lowest_nonlinear_freq = nominal_freq * lowest_nonlinear_ratio >> SCHED_CAPACITY_SHIFT; 660 661 /* Switch to khz */ 662 return lowest_nonlinear_freq * 1000; 663 } 664 665 static int amd_pstate_set_boost(struct cpufreq_policy *policy, int state) 666 { 667 struct amd_cpudata *cpudata = policy->driver_data; 668 int ret; 669 670 if (!cpudata->boost_supported) { 671 pr_err("Boost mode is not supported by this processor or SBIOS\n"); 672 return -EINVAL; 673 } 674 675 if (state) 676 policy->cpuinfo.max_freq = cpudata->max_freq; 677 else 678 policy->cpuinfo.max_freq = cpudata->nominal_freq * 1000; 679 680 policy->max = policy->cpuinfo.max_freq; 681 682 ret = freq_qos_update_request(&cpudata->req[1], 683 policy->cpuinfo.max_freq); 684 if (ret < 0) 685 return ret; 686 687 return 0; 688 } 689 690 static void amd_pstate_boost_init(struct amd_cpudata *cpudata) 691 { 692 u32 highest_perf, nominal_perf; 693 694 highest_perf = READ_ONCE(cpudata->highest_perf); 695 nominal_perf = READ_ONCE(cpudata->nominal_perf); 696 697 if (highest_perf <= nominal_perf) 698 return; 699 700 cpudata->boost_supported = true; 701 current_pstate_driver->boost_enabled = true; 702 } 703 704 static void amd_perf_ctl_reset(unsigned int cpu) 705 { 706 wrmsrl_on_cpu(cpu, MSR_AMD_PERF_CTL, 0); 707 } 708 709 static int amd_pstate_cpu_init(struct cpufreq_policy *policy) 710 { 711 int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret; 712 struct device *dev; 713 struct amd_cpudata *cpudata; 714 715 /* 716 * Resetting PERF_CTL_MSR will put the CPU in P0 frequency, 717 * which is ideal for initialization process. 718 */ 719 amd_perf_ctl_reset(policy->cpu); 720 dev = get_cpu_device(policy->cpu); 721 if (!dev) 722 return -ENODEV; 723 724 cpudata = kzalloc(sizeof(*cpudata), GFP_KERNEL); 725 if (!cpudata) 726 return -ENOMEM; 727 728 cpudata->cpu = policy->cpu; 729 730 ret = amd_pstate_init_perf(cpudata); 731 if (ret) 732 goto free_cpudata1; 733 734 min_freq = amd_get_min_freq(cpudata); 735 max_freq = amd_get_max_freq(cpudata); 736 nominal_freq = amd_get_nominal_freq(cpudata); 737 lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata); 738 739 if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) { 740 dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n", 741 min_freq, max_freq); 742 ret = -EINVAL; 743 goto free_cpudata1; 744 } 745 746 policy->cpuinfo.transition_latency = AMD_PSTATE_TRANSITION_LATENCY; 747 policy->transition_delay_us = AMD_PSTATE_TRANSITION_DELAY; 748 749 policy->min = min_freq; 750 policy->max = max_freq; 751 752 policy->cpuinfo.min_freq = min_freq; 753 policy->cpuinfo.max_freq = max_freq; 754 755 /* It will be updated by governor */ 756 policy->cur = policy->cpuinfo.min_freq; 757 758 if (boot_cpu_has(X86_FEATURE_CPPC)) 759 policy->fast_switch_possible = true; 760 761 ret = freq_qos_add_request(&policy->constraints, &cpudata->req[0], 762 FREQ_QOS_MIN, policy->cpuinfo.min_freq); 763 if (ret < 0) { 764 dev_err(dev, "Failed to add min-freq constraint (%d)\n", ret); 765 goto free_cpudata1; 766 } 767 768 ret = freq_qos_add_request(&policy->constraints, &cpudata->req[1], 769 FREQ_QOS_MAX, policy->cpuinfo.max_freq); 770 if (ret < 0) { 771 dev_err(dev, "Failed to add max-freq constraint (%d)\n", ret); 772 goto free_cpudata2; 773 } 774 775 /* Initial processor data capability frequencies */ 776 cpudata->max_freq = max_freq; 777 cpudata->min_freq = min_freq; 778 cpudata->max_limit_freq = max_freq; 779 cpudata->min_limit_freq = min_freq; 780 cpudata->nominal_freq = nominal_freq; 781 cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq; 782 783 policy->driver_data = cpudata; 784 785 amd_pstate_boost_init(cpudata); 786 if (!current_pstate_driver->adjust_perf) 787 current_pstate_driver->adjust_perf = amd_pstate_adjust_perf; 788 789 return 0; 790 791 free_cpudata2: 792 freq_qos_remove_request(&cpudata->req[0]); 793 free_cpudata1: 794 kfree(cpudata); 795 return ret; 796 } 797 798 static int amd_pstate_cpu_exit(struct cpufreq_policy *policy) 799 { 800 struct amd_cpudata *cpudata = policy->driver_data; 801 802 freq_qos_remove_request(&cpudata->req[1]); 803 freq_qos_remove_request(&cpudata->req[0]); 804 policy->fast_switch_possible = false; 805 kfree(cpudata); 806 807 return 0; 808 } 809 810 static int amd_pstate_cpu_resume(struct cpufreq_policy *policy) 811 { 812 int ret; 813 814 ret = amd_pstate_enable(true); 815 if (ret) 816 pr_err("failed to enable amd-pstate during resume, return %d\n", ret); 817 818 return ret; 819 } 820 821 static int amd_pstate_cpu_suspend(struct cpufreq_policy *policy) 822 { 823 int ret; 824 825 ret = amd_pstate_enable(false); 826 if (ret) 827 pr_err("failed to disable amd-pstate during suspend, return %d\n", ret); 828 829 return ret; 830 } 831 832 /* Sysfs attributes */ 833 834 /* 835 * This frequency is to indicate the maximum hardware frequency. 836 * If boost is not active but supported, the frequency will be larger than the 837 * one in cpuinfo. 838 */ 839 static ssize_t show_amd_pstate_max_freq(struct cpufreq_policy *policy, 840 char *buf) 841 { 842 int max_freq; 843 struct amd_cpudata *cpudata = policy->driver_data; 844 845 max_freq = amd_get_max_freq(cpudata); 846 if (max_freq < 0) 847 return max_freq; 848 849 return sysfs_emit(buf, "%u\n", max_freq); 850 } 851 852 static ssize_t show_amd_pstate_lowest_nonlinear_freq(struct cpufreq_policy *policy, 853 char *buf) 854 { 855 int freq; 856 struct amd_cpudata *cpudata = policy->driver_data; 857 858 freq = amd_get_lowest_nonlinear_freq(cpudata); 859 if (freq < 0) 860 return freq; 861 862 return sysfs_emit(buf, "%u\n", freq); 863 } 864 865 /* 866 * In some of ASICs, the highest_perf is not the one in the _CPC table, so we 867 * need to expose it to sysfs. 868 */ 869 static ssize_t show_amd_pstate_highest_perf(struct cpufreq_policy *policy, 870 char *buf) 871 { 872 u32 perf; 873 struct amd_cpudata *cpudata = policy->driver_data; 874 875 perf = READ_ONCE(cpudata->highest_perf); 876 877 return sysfs_emit(buf, "%u\n", perf); 878 } 879 880 static ssize_t show_energy_performance_available_preferences( 881 struct cpufreq_policy *policy, char *buf) 882 { 883 int i = 0; 884 int offset = 0; 885 struct amd_cpudata *cpudata = policy->driver_data; 886 887 if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) 888 return sysfs_emit_at(buf, offset, "%s\n", 889 energy_perf_strings[EPP_INDEX_PERFORMANCE]); 890 891 while (energy_perf_strings[i] != NULL) 892 offset += sysfs_emit_at(buf, offset, "%s ", energy_perf_strings[i++]); 893 894 offset += sysfs_emit_at(buf, offset, "\n"); 895 896 return offset; 897 } 898 899 static ssize_t store_energy_performance_preference( 900 struct cpufreq_policy *policy, const char *buf, size_t count) 901 { 902 struct amd_cpudata *cpudata = policy->driver_data; 903 char str_preference[21]; 904 ssize_t ret; 905 906 ret = sscanf(buf, "%20s", str_preference); 907 if (ret != 1) 908 return -EINVAL; 909 910 ret = match_string(energy_perf_strings, -1, str_preference); 911 if (ret < 0) 912 return -EINVAL; 913 914 mutex_lock(&amd_pstate_limits_lock); 915 ret = amd_pstate_set_energy_pref_index(cpudata, ret); 916 mutex_unlock(&amd_pstate_limits_lock); 917 918 return ret ?: count; 919 } 920 921 static ssize_t show_energy_performance_preference( 922 struct cpufreq_policy *policy, char *buf) 923 { 924 struct amd_cpudata *cpudata = policy->driver_data; 925 int preference; 926 927 preference = amd_pstate_get_energy_pref_index(cpudata); 928 if (preference < 0) 929 return preference; 930 931 return sysfs_emit(buf, "%s\n", energy_perf_strings[preference]); 932 } 933 934 static void amd_pstate_driver_cleanup(void) 935 { 936 amd_pstate_enable(false); 937 cppc_state = AMD_PSTATE_DISABLE; 938 current_pstate_driver = NULL; 939 } 940 941 static int amd_pstate_register_driver(int mode) 942 { 943 int ret; 944 945 if (mode == AMD_PSTATE_PASSIVE || mode == AMD_PSTATE_GUIDED) 946 current_pstate_driver = &amd_pstate_driver; 947 else if (mode == AMD_PSTATE_ACTIVE) 948 current_pstate_driver = &amd_pstate_epp_driver; 949 else 950 return -EINVAL; 951 952 cppc_state = mode; 953 ret = cpufreq_register_driver(current_pstate_driver); 954 if (ret) { 955 amd_pstate_driver_cleanup(); 956 return ret; 957 } 958 return 0; 959 } 960 961 static int amd_pstate_unregister_driver(int dummy) 962 { 963 cpufreq_unregister_driver(current_pstate_driver); 964 amd_pstate_driver_cleanup(); 965 return 0; 966 } 967 968 static int amd_pstate_change_mode_without_dvr_change(int mode) 969 { 970 int cpu = 0; 971 972 cppc_state = mode; 973 974 if (boot_cpu_has(X86_FEATURE_CPPC) || cppc_state == AMD_PSTATE_ACTIVE) 975 return 0; 976 977 for_each_present_cpu(cpu) { 978 cppc_set_auto_sel(cpu, (cppc_state == AMD_PSTATE_PASSIVE) ? 0 : 1); 979 } 980 981 return 0; 982 } 983 984 static int amd_pstate_change_driver_mode(int mode) 985 { 986 int ret; 987 988 ret = amd_pstate_unregister_driver(0); 989 if (ret) 990 return ret; 991 992 ret = amd_pstate_register_driver(mode); 993 if (ret) 994 return ret; 995 996 return 0; 997 } 998 999 static cppc_mode_transition_fn mode_state_machine[AMD_PSTATE_MAX][AMD_PSTATE_MAX] = { 1000 [AMD_PSTATE_DISABLE] = { 1001 [AMD_PSTATE_DISABLE] = NULL, 1002 [AMD_PSTATE_PASSIVE] = amd_pstate_register_driver, 1003 [AMD_PSTATE_ACTIVE] = amd_pstate_register_driver, 1004 [AMD_PSTATE_GUIDED] = amd_pstate_register_driver, 1005 }, 1006 [AMD_PSTATE_PASSIVE] = { 1007 [AMD_PSTATE_DISABLE] = amd_pstate_unregister_driver, 1008 [AMD_PSTATE_PASSIVE] = NULL, 1009 [AMD_PSTATE_ACTIVE] = amd_pstate_change_driver_mode, 1010 [AMD_PSTATE_GUIDED] = amd_pstate_change_mode_without_dvr_change, 1011 }, 1012 [AMD_PSTATE_ACTIVE] = { 1013 [AMD_PSTATE_DISABLE] = amd_pstate_unregister_driver, 1014 [AMD_PSTATE_PASSIVE] = amd_pstate_change_driver_mode, 1015 [AMD_PSTATE_ACTIVE] = NULL, 1016 [AMD_PSTATE_GUIDED] = amd_pstate_change_driver_mode, 1017 }, 1018 [AMD_PSTATE_GUIDED] = { 1019 [AMD_PSTATE_DISABLE] = amd_pstate_unregister_driver, 1020 [AMD_PSTATE_PASSIVE] = amd_pstate_change_mode_without_dvr_change, 1021 [AMD_PSTATE_ACTIVE] = amd_pstate_change_driver_mode, 1022 [AMD_PSTATE_GUIDED] = NULL, 1023 }, 1024 }; 1025 1026 static ssize_t amd_pstate_show_status(char *buf) 1027 { 1028 if (!current_pstate_driver) 1029 return sysfs_emit(buf, "disable\n"); 1030 1031 return sysfs_emit(buf, "%s\n", amd_pstate_mode_string[cppc_state]); 1032 } 1033 1034 static int amd_pstate_update_status(const char *buf, size_t size) 1035 { 1036 int mode_idx; 1037 1038 if (size > strlen("passive") || size < strlen("active")) 1039 return -EINVAL; 1040 1041 mode_idx = get_mode_idx_from_str(buf, size); 1042 1043 if (mode_idx < 0 || mode_idx >= AMD_PSTATE_MAX) 1044 return -EINVAL; 1045 1046 if (mode_state_machine[cppc_state][mode_idx]) 1047 return mode_state_machine[cppc_state][mode_idx](mode_idx); 1048 1049 return 0; 1050 } 1051 1052 static ssize_t status_show(struct device *dev, 1053 struct device_attribute *attr, char *buf) 1054 { 1055 ssize_t ret; 1056 1057 mutex_lock(&amd_pstate_driver_lock); 1058 ret = amd_pstate_show_status(buf); 1059 mutex_unlock(&amd_pstate_driver_lock); 1060 1061 return ret; 1062 } 1063 1064 static ssize_t status_store(struct device *a, struct device_attribute *b, 1065 const char *buf, size_t count) 1066 { 1067 char *p = memchr(buf, '\n', count); 1068 int ret; 1069 1070 mutex_lock(&amd_pstate_driver_lock); 1071 ret = amd_pstate_update_status(buf, p ? p - buf : count); 1072 mutex_unlock(&amd_pstate_driver_lock); 1073 1074 return ret < 0 ? ret : count; 1075 } 1076 1077 cpufreq_freq_attr_ro(amd_pstate_max_freq); 1078 cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq); 1079 1080 cpufreq_freq_attr_ro(amd_pstate_highest_perf); 1081 cpufreq_freq_attr_rw(energy_performance_preference); 1082 cpufreq_freq_attr_ro(energy_performance_available_preferences); 1083 static DEVICE_ATTR_RW(status); 1084 1085 static struct freq_attr *amd_pstate_attr[] = { 1086 &amd_pstate_max_freq, 1087 &amd_pstate_lowest_nonlinear_freq, 1088 &amd_pstate_highest_perf, 1089 NULL, 1090 }; 1091 1092 static struct freq_attr *amd_pstate_epp_attr[] = { 1093 &amd_pstate_max_freq, 1094 &amd_pstate_lowest_nonlinear_freq, 1095 &amd_pstate_highest_perf, 1096 &energy_performance_preference, 1097 &energy_performance_available_preferences, 1098 NULL, 1099 }; 1100 1101 static struct attribute *pstate_global_attributes[] = { 1102 &dev_attr_status.attr, 1103 NULL 1104 }; 1105 1106 static const struct attribute_group amd_pstate_global_attr_group = { 1107 .name = "amd_pstate", 1108 .attrs = pstate_global_attributes, 1109 }; 1110 1111 static bool amd_pstate_acpi_pm_profile_server(void) 1112 { 1113 switch (acpi_gbl_FADT.preferred_profile) { 1114 case PM_ENTERPRISE_SERVER: 1115 case PM_SOHO_SERVER: 1116 case PM_PERFORMANCE_SERVER: 1117 return true; 1118 } 1119 return false; 1120 } 1121 1122 static bool amd_pstate_acpi_pm_profile_undefined(void) 1123 { 1124 if (acpi_gbl_FADT.preferred_profile == PM_UNSPECIFIED) 1125 return true; 1126 if (acpi_gbl_FADT.preferred_profile >= NR_PM_PROFILES) 1127 return true; 1128 return false; 1129 } 1130 1131 static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy) 1132 { 1133 int min_freq, max_freq, nominal_freq, lowest_nonlinear_freq, ret; 1134 struct amd_cpudata *cpudata; 1135 struct device *dev; 1136 u64 value; 1137 1138 /* 1139 * Resetting PERF_CTL_MSR will put the CPU in P0 frequency, 1140 * which is ideal for initialization process. 1141 */ 1142 amd_perf_ctl_reset(policy->cpu); 1143 dev = get_cpu_device(policy->cpu); 1144 if (!dev) 1145 return -ENODEV; 1146 1147 cpudata = kzalloc(sizeof(*cpudata), GFP_KERNEL); 1148 if (!cpudata) 1149 return -ENOMEM; 1150 1151 cpudata->cpu = policy->cpu; 1152 cpudata->epp_policy = 0; 1153 1154 ret = amd_pstate_init_perf(cpudata); 1155 if (ret) 1156 goto free_cpudata1; 1157 1158 min_freq = amd_get_min_freq(cpudata); 1159 max_freq = amd_get_max_freq(cpudata); 1160 nominal_freq = amd_get_nominal_freq(cpudata); 1161 lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata); 1162 if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) { 1163 dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n", 1164 min_freq, max_freq); 1165 ret = -EINVAL; 1166 goto free_cpudata1; 1167 } 1168 1169 policy->cpuinfo.min_freq = min_freq; 1170 policy->cpuinfo.max_freq = max_freq; 1171 /* It will be updated by governor */ 1172 policy->cur = policy->cpuinfo.min_freq; 1173 1174 /* Initial processor data capability frequencies */ 1175 cpudata->max_freq = max_freq; 1176 cpudata->min_freq = min_freq; 1177 cpudata->nominal_freq = nominal_freq; 1178 cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq; 1179 1180 policy->driver_data = cpudata; 1181 1182 cpudata->epp_cached = amd_pstate_get_epp(cpudata, 0); 1183 1184 policy->min = policy->cpuinfo.min_freq; 1185 policy->max = policy->cpuinfo.max_freq; 1186 1187 /* 1188 * Set the policy to provide a valid fallback value in case 1189 * the default cpufreq governor is neither powersave nor performance. 1190 */ 1191 if (amd_pstate_acpi_pm_profile_server() || 1192 amd_pstate_acpi_pm_profile_undefined()) 1193 policy->policy = CPUFREQ_POLICY_PERFORMANCE; 1194 else 1195 policy->policy = CPUFREQ_POLICY_POWERSAVE; 1196 1197 if (boot_cpu_has(X86_FEATURE_CPPC)) { 1198 ret = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, &value); 1199 if (ret) 1200 return ret; 1201 WRITE_ONCE(cpudata->cppc_req_cached, value); 1202 1203 ret = rdmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_CAP1, &value); 1204 if (ret) 1205 return ret; 1206 WRITE_ONCE(cpudata->cppc_cap1_cached, value); 1207 } 1208 amd_pstate_boost_init(cpudata); 1209 1210 return 0; 1211 1212 free_cpudata1: 1213 kfree(cpudata); 1214 return ret; 1215 } 1216 1217 static int amd_pstate_epp_cpu_exit(struct cpufreq_policy *policy) 1218 { 1219 struct amd_cpudata *cpudata = policy->driver_data; 1220 1221 if (cpudata) { 1222 kfree(cpudata); 1223 policy->driver_data = NULL; 1224 } 1225 1226 pr_debug("CPU %d exiting\n", policy->cpu); 1227 return 0; 1228 } 1229 1230 static void amd_pstate_epp_update_limit(struct cpufreq_policy *policy) 1231 { 1232 struct amd_cpudata *cpudata = policy->driver_data; 1233 u32 max_perf, min_perf, min_limit_perf, max_limit_perf; 1234 u64 value; 1235 s16 epp; 1236 1237 max_perf = READ_ONCE(cpudata->highest_perf); 1238 min_perf = READ_ONCE(cpudata->lowest_perf); 1239 max_limit_perf = div_u64(policy->max * cpudata->highest_perf, cpudata->max_freq); 1240 min_limit_perf = div_u64(policy->min * cpudata->highest_perf, cpudata->max_freq); 1241 1242 WRITE_ONCE(cpudata->max_limit_perf, max_limit_perf); 1243 WRITE_ONCE(cpudata->min_limit_perf, min_limit_perf); 1244 1245 max_perf = clamp_t(unsigned long, max_perf, cpudata->min_limit_perf, 1246 cpudata->max_limit_perf); 1247 min_perf = clamp_t(unsigned long, min_perf, cpudata->min_limit_perf, 1248 cpudata->max_limit_perf); 1249 value = READ_ONCE(cpudata->cppc_req_cached); 1250 1251 if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) 1252 min_perf = max_perf; 1253 1254 /* Initial min/max values for CPPC Performance Controls Register */ 1255 value &= ~AMD_CPPC_MIN_PERF(~0L); 1256 value |= AMD_CPPC_MIN_PERF(min_perf); 1257 1258 value &= ~AMD_CPPC_MAX_PERF(~0L); 1259 value |= AMD_CPPC_MAX_PERF(max_perf); 1260 1261 /* CPPC EPP feature require to set zero to the desire perf bit */ 1262 value &= ~AMD_CPPC_DES_PERF(~0L); 1263 value |= AMD_CPPC_DES_PERF(0); 1264 1265 cpudata->epp_policy = cpudata->policy; 1266 1267 /* Get BIOS pre-defined epp value */ 1268 epp = amd_pstate_get_epp(cpudata, value); 1269 if (epp < 0) { 1270 /** 1271 * This return value can only be negative for shared_memory 1272 * systems where EPP register read/write not supported. 1273 */ 1274 return; 1275 } 1276 1277 if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE) 1278 epp = 0; 1279 1280 /* Set initial EPP value */ 1281 if (boot_cpu_has(X86_FEATURE_CPPC)) { 1282 value &= ~GENMASK_ULL(31, 24); 1283 value |= (u64)epp << 24; 1284 } 1285 1286 WRITE_ONCE(cpudata->cppc_req_cached, value); 1287 amd_pstate_set_epp(cpudata, epp); 1288 } 1289 1290 static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy) 1291 { 1292 struct amd_cpudata *cpudata = policy->driver_data; 1293 1294 if (!policy->cpuinfo.max_freq) 1295 return -ENODEV; 1296 1297 pr_debug("set_policy: cpuinfo.max %u policy->max %u\n", 1298 policy->cpuinfo.max_freq, policy->max); 1299 1300 cpudata->policy = policy->policy; 1301 1302 amd_pstate_epp_update_limit(policy); 1303 1304 return 0; 1305 } 1306 1307 static void amd_pstate_epp_reenable(struct amd_cpudata *cpudata) 1308 { 1309 struct cppc_perf_ctrls perf_ctrls; 1310 u64 value, max_perf; 1311 int ret; 1312 1313 ret = amd_pstate_enable(true); 1314 if (ret) 1315 pr_err("failed to enable amd pstate during resume, return %d\n", ret); 1316 1317 value = READ_ONCE(cpudata->cppc_req_cached); 1318 max_perf = READ_ONCE(cpudata->highest_perf); 1319 1320 if (boot_cpu_has(X86_FEATURE_CPPC)) { 1321 wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value); 1322 } else { 1323 perf_ctrls.max_perf = max_perf; 1324 perf_ctrls.energy_perf = AMD_CPPC_ENERGY_PERF_PREF(cpudata->epp_cached); 1325 cppc_set_perf(cpudata->cpu, &perf_ctrls); 1326 } 1327 } 1328 1329 static int amd_pstate_epp_cpu_online(struct cpufreq_policy *policy) 1330 { 1331 struct amd_cpudata *cpudata = policy->driver_data; 1332 1333 pr_debug("AMD CPU Core %d going online\n", cpudata->cpu); 1334 1335 if (cppc_state == AMD_PSTATE_ACTIVE) { 1336 amd_pstate_epp_reenable(cpudata); 1337 cpudata->suspended = false; 1338 } 1339 1340 return 0; 1341 } 1342 1343 static void amd_pstate_epp_offline(struct cpufreq_policy *policy) 1344 { 1345 struct amd_cpudata *cpudata = policy->driver_data; 1346 struct cppc_perf_ctrls perf_ctrls; 1347 int min_perf; 1348 u64 value; 1349 1350 min_perf = READ_ONCE(cpudata->lowest_perf); 1351 value = READ_ONCE(cpudata->cppc_req_cached); 1352 1353 mutex_lock(&amd_pstate_limits_lock); 1354 if (boot_cpu_has(X86_FEATURE_CPPC)) { 1355 cpudata->epp_policy = CPUFREQ_POLICY_UNKNOWN; 1356 1357 /* Set max perf same as min perf */ 1358 value &= ~AMD_CPPC_MAX_PERF(~0L); 1359 value |= AMD_CPPC_MAX_PERF(min_perf); 1360 value &= ~AMD_CPPC_MIN_PERF(~0L); 1361 value |= AMD_CPPC_MIN_PERF(min_perf); 1362 wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value); 1363 } else { 1364 perf_ctrls.desired_perf = 0; 1365 perf_ctrls.max_perf = min_perf; 1366 perf_ctrls.energy_perf = AMD_CPPC_ENERGY_PERF_PREF(HWP_EPP_BALANCE_POWERSAVE); 1367 cppc_set_perf(cpudata->cpu, &perf_ctrls); 1368 } 1369 mutex_unlock(&amd_pstate_limits_lock); 1370 } 1371 1372 static int amd_pstate_epp_cpu_offline(struct cpufreq_policy *policy) 1373 { 1374 struct amd_cpudata *cpudata = policy->driver_data; 1375 1376 pr_debug("AMD CPU Core %d going offline\n", cpudata->cpu); 1377 1378 if (cpudata->suspended) 1379 return 0; 1380 1381 if (cppc_state == AMD_PSTATE_ACTIVE) 1382 amd_pstate_epp_offline(policy); 1383 1384 return 0; 1385 } 1386 1387 static int amd_pstate_epp_verify_policy(struct cpufreq_policy_data *policy) 1388 { 1389 cpufreq_verify_within_cpu_limits(policy); 1390 pr_debug("policy_max =%d, policy_min=%d\n", policy->max, policy->min); 1391 return 0; 1392 } 1393 1394 static int amd_pstate_epp_suspend(struct cpufreq_policy *policy) 1395 { 1396 struct amd_cpudata *cpudata = policy->driver_data; 1397 int ret; 1398 1399 /* avoid suspending when EPP is not enabled */ 1400 if (cppc_state != AMD_PSTATE_ACTIVE) 1401 return 0; 1402 1403 /* set this flag to avoid setting core offline*/ 1404 cpudata->suspended = true; 1405 1406 /* disable CPPC in lowlevel firmware */ 1407 ret = amd_pstate_enable(false); 1408 if (ret) 1409 pr_err("failed to suspend, return %d\n", ret); 1410 1411 return 0; 1412 } 1413 1414 static int amd_pstate_epp_resume(struct cpufreq_policy *policy) 1415 { 1416 struct amd_cpudata *cpudata = policy->driver_data; 1417 1418 if (cpudata->suspended) { 1419 mutex_lock(&amd_pstate_limits_lock); 1420 1421 /* enable amd pstate from suspend state*/ 1422 amd_pstate_epp_reenable(cpudata); 1423 1424 mutex_unlock(&amd_pstate_limits_lock); 1425 1426 cpudata->suspended = false; 1427 } 1428 1429 return 0; 1430 } 1431 1432 static struct cpufreq_driver amd_pstate_driver = { 1433 .flags = CPUFREQ_CONST_LOOPS | CPUFREQ_NEED_UPDATE_LIMITS, 1434 .verify = amd_pstate_verify, 1435 .target = amd_pstate_target, 1436 .fast_switch = amd_pstate_fast_switch, 1437 .init = amd_pstate_cpu_init, 1438 .exit = amd_pstate_cpu_exit, 1439 .suspend = amd_pstate_cpu_suspend, 1440 .resume = amd_pstate_cpu_resume, 1441 .set_boost = amd_pstate_set_boost, 1442 .name = "amd-pstate", 1443 .attr = amd_pstate_attr, 1444 }; 1445 1446 static struct cpufreq_driver amd_pstate_epp_driver = { 1447 .flags = CPUFREQ_CONST_LOOPS, 1448 .verify = amd_pstate_epp_verify_policy, 1449 .setpolicy = amd_pstate_epp_set_policy, 1450 .init = amd_pstate_epp_cpu_init, 1451 .exit = amd_pstate_epp_cpu_exit, 1452 .offline = amd_pstate_epp_cpu_offline, 1453 .online = amd_pstate_epp_cpu_online, 1454 .suspend = amd_pstate_epp_suspend, 1455 .resume = amd_pstate_epp_resume, 1456 .name = "amd-pstate-epp", 1457 .attr = amd_pstate_epp_attr, 1458 }; 1459 1460 static int __init amd_pstate_set_driver(int mode_idx) 1461 { 1462 if (mode_idx >= AMD_PSTATE_DISABLE && mode_idx < AMD_PSTATE_MAX) { 1463 cppc_state = mode_idx; 1464 if (cppc_state == AMD_PSTATE_DISABLE) 1465 pr_info("driver is explicitly disabled\n"); 1466 1467 if (cppc_state == AMD_PSTATE_ACTIVE) 1468 current_pstate_driver = &amd_pstate_epp_driver; 1469 1470 if (cppc_state == AMD_PSTATE_PASSIVE || cppc_state == AMD_PSTATE_GUIDED) 1471 current_pstate_driver = &amd_pstate_driver; 1472 1473 return 0; 1474 } 1475 1476 return -EINVAL; 1477 } 1478 1479 static int __init amd_pstate_init(void) 1480 { 1481 struct device *dev_root; 1482 int ret; 1483 1484 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) 1485 return -ENODEV; 1486 1487 if (!acpi_cpc_valid()) { 1488 pr_warn_once("the _CPC object is not present in SBIOS or ACPI disabled\n"); 1489 return -ENODEV; 1490 } 1491 1492 /* don't keep reloading if cpufreq_driver exists */ 1493 if (cpufreq_get_current_driver()) 1494 return -EEXIST; 1495 1496 switch (cppc_state) { 1497 case AMD_PSTATE_UNDEFINED: 1498 /* Disable on the following configs by default: 1499 * 1. Undefined platforms 1500 * 2. Server platforms 1501 * 3. Shared memory designs 1502 */ 1503 if (amd_pstate_acpi_pm_profile_undefined() || 1504 amd_pstate_acpi_pm_profile_server() || 1505 !boot_cpu_has(X86_FEATURE_CPPC)) { 1506 pr_info("driver load is disabled, boot with specific mode to enable this\n"); 1507 return -ENODEV; 1508 } 1509 ret = amd_pstate_set_driver(CONFIG_X86_AMD_PSTATE_DEFAULT_MODE); 1510 if (ret) 1511 return ret; 1512 break; 1513 case AMD_PSTATE_DISABLE: 1514 return -ENODEV; 1515 case AMD_PSTATE_PASSIVE: 1516 case AMD_PSTATE_ACTIVE: 1517 case AMD_PSTATE_GUIDED: 1518 break; 1519 default: 1520 return -EINVAL; 1521 } 1522 1523 /* capability check */ 1524 if (boot_cpu_has(X86_FEATURE_CPPC)) { 1525 pr_debug("AMD CPPC MSR based functionality is supported\n"); 1526 if (cppc_state != AMD_PSTATE_ACTIVE) 1527 current_pstate_driver->adjust_perf = amd_pstate_adjust_perf; 1528 } else { 1529 pr_debug("AMD CPPC shared memory based functionality is supported\n"); 1530 static_call_update(amd_pstate_enable, cppc_enable); 1531 static_call_update(amd_pstate_init_perf, cppc_init_perf); 1532 static_call_update(amd_pstate_update_perf, cppc_update_perf); 1533 } 1534 1535 /* enable amd pstate feature */ 1536 ret = amd_pstate_enable(true); 1537 if (ret) { 1538 pr_err("failed to enable with return %d\n", ret); 1539 return ret; 1540 } 1541 1542 ret = cpufreq_register_driver(current_pstate_driver); 1543 if (ret) 1544 pr_err("failed to register with return %d\n", ret); 1545 1546 dev_root = bus_get_dev_root(&cpu_subsys); 1547 if (dev_root) { 1548 ret = sysfs_create_group(&dev_root->kobj, &amd_pstate_global_attr_group); 1549 put_device(dev_root); 1550 if (ret) { 1551 pr_err("sysfs attribute export failed with error %d.\n", ret); 1552 goto global_attr_free; 1553 } 1554 } 1555 1556 return ret; 1557 1558 global_attr_free: 1559 cpufreq_unregister_driver(current_pstate_driver); 1560 return ret; 1561 } 1562 device_initcall(amd_pstate_init); 1563 1564 static int __init amd_pstate_param(char *str) 1565 { 1566 size_t size; 1567 int mode_idx; 1568 1569 if (!str) 1570 return -EINVAL; 1571 1572 size = strlen(str); 1573 mode_idx = get_mode_idx_from_str(str, size); 1574 1575 return amd_pstate_set_driver(mode_idx); 1576 } 1577 early_param("amd_pstate", amd_pstate_param); 1578 1579 MODULE_AUTHOR("Huang Rui <ray.huang@amd.com>"); 1580 MODULE_DESCRIPTION("AMD Processor P-state Frequency Driver"); 1581