1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * CPPC (Collaborative Processor Performance Control) driver for 4 * interfacing with the CPUfreq layer and governors. See 5 * cppc_acpi.c for CPPC specific methods. 6 * 7 * (C) Copyright 2014, 2015 Linaro Ltd. 8 * Author: Ashwin Chaugule <ashwin.chaugule@linaro.org> 9 */ 10 11 #define pr_fmt(fmt) "CPPC Cpufreq:" fmt 12 13 #include <linux/arch_topology.h> 14 #include <linux/kernel.h> 15 #include <linux/module.h> 16 #include <linux/delay.h> 17 #include <linux/cpu.h> 18 #include <linux/cpufreq.h> 19 #include <linux/dmi.h> 20 #include <linux/irq_work.h> 21 #include <linux/kthread.h> 22 #include <linux/time.h> 23 #include <linux/vmalloc.h> 24 #include <uapi/linux/sched/types.h> 25 26 #include <asm/unaligned.h> 27 28 #include <acpi/cppc_acpi.h> 29 30 /* Minimum struct length needed for the DMI processor entry we want */ 31 #define DMI_ENTRY_PROCESSOR_MIN_LENGTH 48 32 33 /* Offset in the DMI processor structure for the max frequency */ 34 #define DMI_PROCESSOR_MAX_SPEED 0x14 35 36 /* 37 * This list contains information parsed from per CPU ACPI _CPC and _PSD 38 * structures: e.g. the highest and lowest supported performance, capabilities, 39 * desired performance, level requested etc. Depending on the share_type, not 40 * all CPUs will have an entry in the list. 41 */ 42 static LIST_HEAD(cpu_data_list); 43 44 static bool boost_supported; 45 46 struct cppc_workaround_oem_info { 47 char oem_id[ACPI_OEM_ID_SIZE + 1]; 48 char oem_table_id[ACPI_OEM_TABLE_ID_SIZE + 1]; 49 u32 oem_revision; 50 }; 51 52 static struct cppc_workaround_oem_info wa_info[] = { 53 { 54 .oem_id = "HISI ", 55 .oem_table_id = "HIP07 ", 56 .oem_revision = 0, 57 }, { 58 .oem_id = "HISI ", 59 .oem_table_id = "HIP08 ", 60 .oem_revision = 0, 61 } 62 }; 63 64 #ifdef CONFIG_ACPI_CPPC_CPUFREQ_FIE 65 66 /* Frequency invariance support */ 67 struct cppc_freq_invariance { 68 int cpu; 69 struct irq_work irq_work; 70 struct kthread_work work; 71 struct cppc_perf_fb_ctrs prev_perf_fb_ctrs; 72 struct cppc_cpudata *cpu_data; 73 }; 74 75 static DEFINE_PER_CPU(struct cppc_freq_invariance, cppc_freq_inv); 76 static struct kthread_worker *kworker_fie; 77 78 static struct cpufreq_driver cppc_cpufreq_driver; 79 static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu); 80 static int cppc_perf_from_fbctrs(struct cppc_cpudata *cpu_data, 81 struct cppc_perf_fb_ctrs *fb_ctrs_t0, 82 struct cppc_perf_fb_ctrs *fb_ctrs_t1); 83 84 /** 85 * cppc_scale_freq_workfn - CPPC arch_freq_scale updater for frequency invariance 86 * @work: The work item. 87 * 88 * The CPPC driver register itself with the topology core to provide its own 89 * implementation (cppc_scale_freq_tick()) of topology_scale_freq_tick() which 90 * gets called by the scheduler on every tick. 91 * 92 * Note that the arch specific counters have higher priority than CPPC counters, 93 * if available, though the CPPC driver doesn't need to have any special 94 * handling for that. 95 * 96 * On an invocation of cppc_scale_freq_tick(), we schedule an irq work (since we 97 * reach here from hard-irq context), which then schedules a normal work item 98 * and cppc_scale_freq_workfn() updates the per_cpu arch_freq_scale variable 99 * based on the counter updates since the last tick. 100 */ 101 static void cppc_scale_freq_workfn(struct kthread_work *work) 102 { 103 struct cppc_freq_invariance *cppc_fi; 104 struct cppc_perf_fb_ctrs fb_ctrs = {0}; 105 struct cppc_cpudata *cpu_data; 106 unsigned long local_freq_scale; 107 u64 perf; 108 109 cppc_fi = container_of(work, struct cppc_freq_invariance, work); 110 cpu_data = cppc_fi->cpu_data; 111 112 if (cppc_get_perf_ctrs(cppc_fi->cpu, &fb_ctrs)) { 113 pr_warn("%s: failed to read perf counters\n", __func__); 114 return; 115 } 116 117 perf = cppc_perf_from_fbctrs(cpu_data, &cppc_fi->prev_perf_fb_ctrs, 118 &fb_ctrs); 119 cppc_fi->prev_perf_fb_ctrs = fb_ctrs; 120 121 perf <<= SCHED_CAPACITY_SHIFT; 122 local_freq_scale = div64_u64(perf, cpu_data->perf_caps.highest_perf); 123 124 /* This can happen due to counter's overflow */ 125 if (unlikely(local_freq_scale > 1024)) 126 local_freq_scale = 1024; 127 128 per_cpu(arch_freq_scale, cppc_fi->cpu) = local_freq_scale; 129 } 130 131 static void cppc_irq_work(struct irq_work *irq_work) 132 { 133 struct cppc_freq_invariance *cppc_fi; 134 135 cppc_fi = container_of(irq_work, struct cppc_freq_invariance, irq_work); 136 kthread_queue_work(kworker_fie, &cppc_fi->work); 137 } 138 139 static void cppc_scale_freq_tick(void) 140 { 141 struct cppc_freq_invariance *cppc_fi = &per_cpu(cppc_freq_inv, smp_processor_id()); 142 143 /* 144 * cppc_get_perf_ctrs() can potentially sleep, call that from the right 145 * context. 146 */ 147 irq_work_queue(&cppc_fi->irq_work); 148 } 149 150 static struct scale_freq_data cppc_sftd = { 151 .source = SCALE_FREQ_SOURCE_CPPC, 152 .set_freq_scale = cppc_scale_freq_tick, 153 }; 154 155 static void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy) 156 { 157 struct cppc_freq_invariance *cppc_fi; 158 int cpu, ret; 159 160 if (cppc_cpufreq_driver.get == hisi_cppc_cpufreq_get_rate) 161 return; 162 163 for_each_cpu(cpu, policy->cpus) { 164 cppc_fi = &per_cpu(cppc_freq_inv, cpu); 165 cppc_fi->cpu = cpu; 166 cppc_fi->cpu_data = policy->driver_data; 167 kthread_init_work(&cppc_fi->work, cppc_scale_freq_workfn); 168 init_irq_work(&cppc_fi->irq_work, cppc_irq_work); 169 170 ret = cppc_get_perf_ctrs(cpu, &cppc_fi->prev_perf_fb_ctrs); 171 if (ret) { 172 pr_warn("%s: failed to read perf counters for cpu:%d: %d\n", 173 __func__, cpu, ret); 174 175 /* 176 * Don't abort if the CPU was offline while the driver 177 * was getting registered. 178 */ 179 if (cpu_online(cpu)) 180 return; 181 } 182 } 183 184 /* Register for freq-invariance */ 185 topology_set_scale_freq_source(&cppc_sftd, policy->cpus); 186 } 187 188 /* 189 * We free all the resources on policy's removal and not on CPU removal as the 190 * irq-work are per-cpu and the hotplug core takes care of flushing the pending 191 * irq-works (hint: smpcfd_dying_cpu()) on CPU hotplug. Even if the kthread-work 192 * fires on another CPU after the concerned CPU is removed, it won't harm. 193 * 194 * We just need to make sure to remove them all on policy->exit(). 195 */ 196 static void cppc_cpufreq_cpu_fie_exit(struct cpufreq_policy *policy) 197 { 198 struct cppc_freq_invariance *cppc_fi; 199 int cpu; 200 201 if (cppc_cpufreq_driver.get == hisi_cppc_cpufreq_get_rate) 202 return; 203 204 /* policy->cpus will be empty here, use related_cpus instead */ 205 topology_clear_scale_freq_source(SCALE_FREQ_SOURCE_CPPC, policy->related_cpus); 206 207 for_each_cpu(cpu, policy->related_cpus) { 208 cppc_fi = &per_cpu(cppc_freq_inv, cpu); 209 irq_work_sync(&cppc_fi->irq_work); 210 kthread_cancel_work_sync(&cppc_fi->work); 211 } 212 } 213 214 static void __init cppc_freq_invariance_init(void) 215 { 216 struct sched_attr attr = { 217 .size = sizeof(struct sched_attr), 218 .sched_policy = SCHED_DEADLINE, 219 .sched_nice = 0, 220 .sched_priority = 0, 221 /* 222 * Fake (unused) bandwidth; workaround to "fix" 223 * priority inheritance. 224 */ 225 .sched_runtime = 1000000, 226 .sched_deadline = 10000000, 227 .sched_period = 10000000, 228 }; 229 int ret; 230 231 if (cppc_cpufreq_driver.get == hisi_cppc_cpufreq_get_rate) 232 return; 233 234 kworker_fie = kthread_create_worker(0, "cppc_fie"); 235 if (IS_ERR(kworker_fie)) 236 return; 237 238 ret = sched_setattr_nocheck(kworker_fie->task, &attr); 239 if (ret) { 240 pr_warn("%s: failed to set SCHED_DEADLINE: %d\n", __func__, 241 ret); 242 kthread_destroy_worker(kworker_fie); 243 return; 244 } 245 } 246 247 static void cppc_freq_invariance_exit(void) 248 { 249 if (cppc_cpufreq_driver.get == hisi_cppc_cpufreq_get_rate) 250 return; 251 252 kthread_destroy_worker(kworker_fie); 253 kworker_fie = NULL; 254 } 255 256 #else 257 static inline void cppc_cpufreq_cpu_fie_init(struct cpufreq_policy *policy) 258 { 259 } 260 261 static inline void cppc_cpufreq_cpu_fie_exit(struct cpufreq_policy *policy) 262 { 263 } 264 265 static inline void cppc_freq_invariance_init(void) 266 { 267 } 268 269 static inline void cppc_freq_invariance_exit(void) 270 { 271 } 272 #endif /* CONFIG_ACPI_CPPC_CPUFREQ_FIE */ 273 274 /* Callback function used to retrieve the max frequency from DMI */ 275 static void cppc_find_dmi_mhz(const struct dmi_header *dm, void *private) 276 { 277 const u8 *dmi_data = (const u8 *)dm; 278 u16 *mhz = (u16 *)private; 279 280 if (dm->type == DMI_ENTRY_PROCESSOR && 281 dm->length >= DMI_ENTRY_PROCESSOR_MIN_LENGTH) { 282 u16 val = (u16)get_unaligned((const u16 *) 283 (dmi_data + DMI_PROCESSOR_MAX_SPEED)); 284 *mhz = val > *mhz ? val : *mhz; 285 } 286 } 287 288 /* Look up the max frequency in DMI */ 289 static u64 cppc_get_dmi_max_khz(void) 290 { 291 u16 mhz = 0; 292 293 dmi_walk(cppc_find_dmi_mhz, &mhz); 294 295 /* 296 * Real stupid fallback value, just in case there is no 297 * actual value set. 298 */ 299 mhz = mhz ? mhz : 1; 300 301 return (1000 * mhz); 302 } 303 304 /* 305 * If CPPC lowest_freq and nominal_freq registers are exposed then we can 306 * use them to convert perf to freq and vice versa 307 * 308 * If the perf/freq point lies between Nominal and Lowest, we can treat 309 * (Low perf, Low freq) and (Nom Perf, Nom freq) as 2D co-ordinates of a line 310 * and extrapolate the rest 311 * For perf/freq > Nominal, we use the ratio perf:freq at Nominal for conversion 312 */ 313 static unsigned int cppc_cpufreq_perf_to_khz(struct cppc_cpudata *cpu_data, 314 unsigned int perf) 315 { 316 struct cppc_perf_caps *caps = &cpu_data->perf_caps; 317 static u64 max_khz; 318 u64 mul, div; 319 320 if (caps->lowest_freq && caps->nominal_freq) { 321 if (perf >= caps->nominal_perf) { 322 mul = caps->nominal_freq; 323 div = caps->nominal_perf; 324 } else { 325 mul = caps->nominal_freq - caps->lowest_freq; 326 div = caps->nominal_perf - caps->lowest_perf; 327 } 328 } else { 329 if (!max_khz) 330 max_khz = cppc_get_dmi_max_khz(); 331 mul = max_khz; 332 div = caps->highest_perf; 333 } 334 return (u64)perf * mul / div; 335 } 336 337 static unsigned int cppc_cpufreq_khz_to_perf(struct cppc_cpudata *cpu_data, 338 unsigned int freq) 339 { 340 struct cppc_perf_caps *caps = &cpu_data->perf_caps; 341 static u64 max_khz; 342 u64 mul, div; 343 344 if (caps->lowest_freq && caps->nominal_freq) { 345 if (freq >= caps->nominal_freq) { 346 mul = caps->nominal_perf; 347 div = caps->nominal_freq; 348 } else { 349 mul = caps->lowest_perf; 350 div = caps->lowest_freq; 351 } 352 } else { 353 if (!max_khz) 354 max_khz = cppc_get_dmi_max_khz(); 355 mul = caps->highest_perf; 356 div = max_khz; 357 } 358 359 return (u64)freq * mul / div; 360 } 361 362 static int cppc_cpufreq_set_target(struct cpufreq_policy *policy, 363 unsigned int target_freq, 364 unsigned int relation) 365 366 { 367 struct cppc_cpudata *cpu_data = policy->driver_data; 368 unsigned int cpu = policy->cpu; 369 struct cpufreq_freqs freqs; 370 u32 desired_perf; 371 int ret = 0; 372 373 desired_perf = cppc_cpufreq_khz_to_perf(cpu_data, target_freq); 374 /* Return if it is exactly the same perf */ 375 if (desired_perf == cpu_data->perf_ctrls.desired_perf) 376 return ret; 377 378 cpu_data->perf_ctrls.desired_perf = desired_perf; 379 freqs.old = policy->cur; 380 freqs.new = target_freq; 381 382 cpufreq_freq_transition_begin(policy, &freqs); 383 ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls); 384 cpufreq_freq_transition_end(policy, &freqs, ret != 0); 385 386 if (ret) 387 pr_debug("Failed to set target on CPU:%d. ret:%d\n", 388 cpu, ret); 389 390 return ret; 391 } 392 393 static int cppc_verify_policy(struct cpufreq_policy_data *policy) 394 { 395 cpufreq_verify_within_cpu_limits(policy); 396 return 0; 397 } 398 399 /* 400 * The PCC subspace describes the rate at which platform can accept commands 401 * on the shared PCC channel (including READs which do not count towards freq 402 * transition requests), so ideally we need to use the PCC values as a fallback 403 * if we don't have a platform specific transition_delay_us 404 */ 405 #ifdef CONFIG_ARM64 406 #include <asm/cputype.h> 407 408 static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu) 409 { 410 unsigned long implementor = read_cpuid_implementor(); 411 unsigned long part_num = read_cpuid_part_number(); 412 413 switch (implementor) { 414 case ARM_CPU_IMP_QCOM: 415 switch (part_num) { 416 case QCOM_CPU_PART_FALKOR_V1: 417 case QCOM_CPU_PART_FALKOR: 418 return 10000; 419 } 420 } 421 return cppc_get_transition_latency(cpu) / NSEC_PER_USEC; 422 } 423 424 #else 425 426 static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu) 427 { 428 return cppc_get_transition_latency(cpu) / NSEC_PER_USEC; 429 } 430 #endif 431 432 433 static struct cppc_cpudata *cppc_cpufreq_get_cpu_data(unsigned int cpu) 434 { 435 struct cppc_cpudata *cpu_data; 436 int ret; 437 438 cpu_data = kzalloc(sizeof(struct cppc_cpudata), GFP_KERNEL); 439 if (!cpu_data) 440 goto out; 441 442 if (!zalloc_cpumask_var(&cpu_data->shared_cpu_map, GFP_KERNEL)) 443 goto free_cpu; 444 445 ret = acpi_get_psd_map(cpu, cpu_data); 446 if (ret) { 447 pr_debug("Err parsing CPU%d PSD data: ret:%d\n", cpu, ret); 448 goto free_mask; 449 } 450 451 ret = cppc_get_perf_caps(cpu, &cpu_data->perf_caps); 452 if (ret) { 453 pr_debug("Err reading CPU%d perf caps: ret:%d\n", cpu, ret); 454 goto free_mask; 455 } 456 457 /* Convert the lowest and nominal freq from MHz to KHz */ 458 cpu_data->perf_caps.lowest_freq *= 1000; 459 cpu_data->perf_caps.nominal_freq *= 1000; 460 461 list_add(&cpu_data->node, &cpu_data_list); 462 463 return cpu_data; 464 465 free_mask: 466 free_cpumask_var(cpu_data->shared_cpu_map); 467 free_cpu: 468 kfree(cpu_data); 469 out: 470 return NULL; 471 } 472 473 static void cppc_cpufreq_put_cpu_data(struct cpufreq_policy *policy) 474 { 475 struct cppc_cpudata *cpu_data = policy->driver_data; 476 477 list_del(&cpu_data->node); 478 free_cpumask_var(cpu_data->shared_cpu_map); 479 kfree(cpu_data); 480 policy->driver_data = NULL; 481 } 482 483 static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy) 484 { 485 unsigned int cpu = policy->cpu; 486 struct cppc_cpudata *cpu_data; 487 struct cppc_perf_caps *caps; 488 int ret; 489 490 cpu_data = cppc_cpufreq_get_cpu_data(cpu); 491 if (!cpu_data) { 492 pr_err("Error in acquiring _CPC/_PSD data for CPU%d.\n", cpu); 493 return -ENODEV; 494 } 495 caps = &cpu_data->perf_caps; 496 policy->driver_data = cpu_data; 497 498 /* 499 * Set min to lowest nonlinear perf to avoid any efficiency penalty (see 500 * Section 8.4.7.1.1.5 of ACPI 6.1 spec) 501 */ 502 policy->min = cppc_cpufreq_perf_to_khz(cpu_data, 503 caps->lowest_nonlinear_perf); 504 policy->max = cppc_cpufreq_perf_to_khz(cpu_data, 505 caps->nominal_perf); 506 507 /* 508 * Set cpuinfo.min_freq to Lowest to make the full range of performance 509 * available if userspace wants to use any perf between lowest & lowest 510 * nonlinear perf 511 */ 512 policy->cpuinfo.min_freq = cppc_cpufreq_perf_to_khz(cpu_data, 513 caps->lowest_perf); 514 policy->cpuinfo.max_freq = cppc_cpufreq_perf_to_khz(cpu_data, 515 caps->nominal_perf); 516 517 policy->transition_delay_us = cppc_cpufreq_get_transition_delay_us(cpu); 518 policy->shared_type = cpu_data->shared_type; 519 520 switch (policy->shared_type) { 521 case CPUFREQ_SHARED_TYPE_HW: 522 case CPUFREQ_SHARED_TYPE_NONE: 523 /* Nothing to be done - we'll have a policy for each CPU */ 524 break; 525 case CPUFREQ_SHARED_TYPE_ANY: 526 /* 527 * All CPUs in the domain will share a policy and all cpufreq 528 * operations will use a single cppc_cpudata structure stored 529 * in policy->driver_data. 530 */ 531 cpumask_copy(policy->cpus, cpu_data->shared_cpu_map); 532 break; 533 default: 534 pr_debug("Unsupported CPU co-ord type: %d\n", 535 policy->shared_type); 536 ret = -EFAULT; 537 goto out; 538 } 539 540 /* 541 * If 'highest_perf' is greater than 'nominal_perf', we assume CPU Boost 542 * is supported. 543 */ 544 if (caps->highest_perf > caps->nominal_perf) 545 boost_supported = true; 546 547 /* Set policy->cur to max now. The governors will adjust later. */ 548 policy->cur = cppc_cpufreq_perf_to_khz(cpu_data, caps->highest_perf); 549 cpu_data->perf_ctrls.desired_perf = caps->highest_perf; 550 551 ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls); 552 if (ret) { 553 pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n", 554 caps->highest_perf, cpu, ret); 555 goto out; 556 } 557 558 cppc_cpufreq_cpu_fie_init(policy); 559 return 0; 560 561 out: 562 cppc_cpufreq_put_cpu_data(policy); 563 return ret; 564 } 565 566 static int cppc_cpufreq_cpu_exit(struct cpufreq_policy *policy) 567 { 568 struct cppc_cpudata *cpu_data = policy->driver_data; 569 struct cppc_perf_caps *caps = &cpu_data->perf_caps; 570 unsigned int cpu = policy->cpu; 571 int ret; 572 573 cppc_cpufreq_cpu_fie_exit(policy); 574 575 cpu_data->perf_ctrls.desired_perf = caps->lowest_perf; 576 577 ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls); 578 if (ret) 579 pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n", 580 caps->lowest_perf, cpu, ret); 581 582 cppc_cpufreq_put_cpu_data(policy); 583 return 0; 584 } 585 586 static inline u64 get_delta(u64 t1, u64 t0) 587 { 588 if (t1 > t0 || t0 > ~(u32)0) 589 return t1 - t0; 590 591 return (u32)t1 - (u32)t0; 592 } 593 594 static int cppc_perf_from_fbctrs(struct cppc_cpudata *cpu_data, 595 struct cppc_perf_fb_ctrs *fb_ctrs_t0, 596 struct cppc_perf_fb_ctrs *fb_ctrs_t1) 597 { 598 u64 delta_reference, delta_delivered; 599 u64 reference_perf; 600 601 reference_perf = fb_ctrs_t0->reference_perf; 602 603 delta_reference = get_delta(fb_ctrs_t1->reference, 604 fb_ctrs_t0->reference); 605 delta_delivered = get_delta(fb_ctrs_t1->delivered, 606 fb_ctrs_t0->delivered); 607 608 /* Check to avoid divide-by zero and invalid delivered_perf */ 609 if (!delta_reference || !delta_delivered) 610 return cpu_data->perf_ctrls.desired_perf; 611 612 return (reference_perf * delta_delivered) / delta_reference; 613 } 614 615 static unsigned int cppc_cpufreq_get_rate(unsigned int cpu) 616 { 617 struct cppc_perf_fb_ctrs fb_ctrs_t0 = {0}, fb_ctrs_t1 = {0}; 618 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); 619 struct cppc_cpudata *cpu_data = policy->driver_data; 620 u64 delivered_perf; 621 int ret; 622 623 cpufreq_cpu_put(policy); 624 625 ret = cppc_get_perf_ctrs(cpu, &fb_ctrs_t0); 626 if (ret) 627 return ret; 628 629 udelay(2); /* 2usec delay between sampling */ 630 631 ret = cppc_get_perf_ctrs(cpu, &fb_ctrs_t1); 632 if (ret) 633 return ret; 634 635 delivered_perf = cppc_perf_from_fbctrs(cpu_data, &fb_ctrs_t0, 636 &fb_ctrs_t1); 637 638 return cppc_cpufreq_perf_to_khz(cpu_data, delivered_perf); 639 } 640 641 static int cppc_cpufreq_set_boost(struct cpufreq_policy *policy, int state) 642 { 643 struct cppc_cpudata *cpu_data = policy->driver_data; 644 struct cppc_perf_caps *caps = &cpu_data->perf_caps; 645 int ret; 646 647 if (!boost_supported) { 648 pr_err("BOOST not supported by CPU or firmware\n"); 649 return -EINVAL; 650 } 651 652 if (state) 653 policy->max = cppc_cpufreq_perf_to_khz(cpu_data, 654 caps->highest_perf); 655 else 656 policy->max = cppc_cpufreq_perf_to_khz(cpu_data, 657 caps->nominal_perf); 658 policy->cpuinfo.max_freq = policy->max; 659 660 ret = freq_qos_update_request(policy->max_freq_req, policy->max); 661 if (ret < 0) 662 return ret; 663 664 return 0; 665 } 666 667 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf) 668 { 669 struct cppc_cpudata *cpu_data = policy->driver_data; 670 671 return cpufreq_show_cpus(cpu_data->shared_cpu_map, buf); 672 } 673 cpufreq_freq_attr_ro(freqdomain_cpus); 674 675 static struct freq_attr *cppc_cpufreq_attr[] = { 676 &freqdomain_cpus, 677 NULL, 678 }; 679 680 static struct cpufreq_driver cppc_cpufreq_driver = { 681 .flags = CPUFREQ_CONST_LOOPS, 682 .verify = cppc_verify_policy, 683 .target = cppc_cpufreq_set_target, 684 .get = cppc_cpufreq_get_rate, 685 .init = cppc_cpufreq_cpu_init, 686 .exit = cppc_cpufreq_cpu_exit, 687 .set_boost = cppc_cpufreq_set_boost, 688 .attr = cppc_cpufreq_attr, 689 .name = "cppc_cpufreq", 690 }; 691 692 /* 693 * HISI platform does not support delivered performance counter and 694 * reference performance counter. It can calculate the performance using the 695 * platform specific mechanism. We reuse the desired performance register to 696 * store the real performance calculated by the platform. 697 */ 698 static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu) 699 { 700 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); 701 struct cppc_cpudata *cpu_data = policy->driver_data; 702 u64 desired_perf; 703 int ret; 704 705 cpufreq_cpu_put(policy); 706 707 ret = cppc_get_desired_perf(cpu, &desired_perf); 708 if (ret < 0) 709 return -EIO; 710 711 return cppc_cpufreq_perf_to_khz(cpu_data, desired_perf); 712 } 713 714 static void cppc_check_hisi_workaround(void) 715 { 716 struct acpi_table_header *tbl; 717 acpi_status status = AE_OK; 718 int i; 719 720 status = acpi_get_table(ACPI_SIG_PCCT, 0, &tbl); 721 if (ACPI_FAILURE(status) || !tbl) 722 return; 723 724 for (i = 0; i < ARRAY_SIZE(wa_info); i++) { 725 if (!memcmp(wa_info[i].oem_id, tbl->oem_id, ACPI_OEM_ID_SIZE) && 726 !memcmp(wa_info[i].oem_table_id, tbl->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) && 727 wa_info[i].oem_revision == tbl->oem_revision) { 728 /* Overwrite the get() callback */ 729 cppc_cpufreq_driver.get = hisi_cppc_cpufreq_get_rate; 730 break; 731 } 732 } 733 734 acpi_put_table(tbl); 735 } 736 737 static int __init cppc_cpufreq_init(void) 738 { 739 int ret; 740 741 if ((acpi_disabled) || !acpi_cpc_valid()) 742 return -ENODEV; 743 744 INIT_LIST_HEAD(&cpu_data_list); 745 746 cppc_check_hisi_workaround(); 747 cppc_freq_invariance_init(); 748 749 ret = cpufreq_register_driver(&cppc_cpufreq_driver); 750 if (ret) 751 cppc_freq_invariance_exit(); 752 753 return ret; 754 } 755 756 static inline void free_cpu_data(void) 757 { 758 struct cppc_cpudata *iter, *tmp; 759 760 list_for_each_entry_safe(iter, tmp, &cpu_data_list, node) { 761 free_cpumask_var(iter->shared_cpu_map); 762 list_del(&iter->node); 763 kfree(iter); 764 } 765 766 } 767 768 static void __exit cppc_cpufreq_exit(void) 769 { 770 cpufreq_unregister_driver(&cppc_cpufreq_driver); 771 cppc_freq_invariance_exit(); 772 773 free_cpu_data(); 774 } 775 776 module_exit(cppc_cpufreq_exit); 777 MODULE_AUTHOR("Ashwin Chaugule"); 778 MODULE_DESCRIPTION("CPUFreq driver based on the ACPI CPPC v5.0+ spec"); 779 MODULE_LICENSE("GPL"); 780 781 late_initcall(cppc_cpufreq_init); 782 783 static const struct acpi_device_id cppc_acpi_ids[] __used = { 784 {ACPI_PROCESSOR_DEVICE_HID, }, 785 {} 786 }; 787 788 MODULE_DEVICE_TABLE(acpi, cppc_acpi_ids); 789