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. The conversion is 307 * extrapolated as an affine function passing by the 2 points: 308 * - (Low perf, Low freq) 309 * - (Nominal perf, Nominal perf) 310 */ 311 static unsigned int cppc_cpufreq_perf_to_khz(struct cppc_cpudata *cpu_data, 312 unsigned int perf) 313 { 314 struct cppc_perf_caps *caps = &cpu_data->perf_caps; 315 s64 retval, offset = 0; 316 static u64 max_khz; 317 u64 mul, div; 318 319 if (caps->lowest_freq && caps->nominal_freq) { 320 mul = caps->nominal_freq - caps->lowest_freq; 321 div = caps->nominal_perf - caps->lowest_perf; 322 offset = caps->nominal_freq - div64_u64(caps->nominal_perf * mul, div); 323 } else { 324 if (!max_khz) 325 max_khz = cppc_get_dmi_max_khz(); 326 mul = max_khz; 327 div = caps->highest_perf; 328 } 329 330 retval = offset + div64_u64(perf * mul, div); 331 if (retval >= 0) 332 return retval; 333 return 0; 334 } 335 336 static unsigned int cppc_cpufreq_khz_to_perf(struct cppc_cpudata *cpu_data, 337 unsigned int freq) 338 { 339 struct cppc_perf_caps *caps = &cpu_data->perf_caps; 340 s64 retval, offset = 0; 341 static u64 max_khz; 342 u64 mul, div; 343 344 if (caps->lowest_freq && caps->nominal_freq) { 345 mul = caps->nominal_perf - caps->lowest_perf; 346 div = caps->nominal_freq - caps->lowest_freq; 347 offset = caps->nominal_perf - div64_u64(caps->nominal_freq * mul, div); 348 } else { 349 if (!max_khz) 350 max_khz = cppc_get_dmi_max_khz(); 351 mul = caps->highest_perf; 352 div = max_khz; 353 } 354 355 retval = offset + div64_u64(freq * mul, div); 356 if (retval >= 0) 357 return retval; 358 return 0; 359 } 360 361 static int cppc_cpufreq_set_target(struct cpufreq_policy *policy, 362 unsigned int target_freq, 363 unsigned int relation) 364 365 { 366 struct cppc_cpudata *cpu_data = policy->driver_data; 367 unsigned int cpu = policy->cpu; 368 struct cpufreq_freqs freqs; 369 u32 desired_perf; 370 int ret = 0; 371 372 desired_perf = cppc_cpufreq_khz_to_perf(cpu_data, target_freq); 373 /* Return if it is exactly the same perf */ 374 if (desired_perf == cpu_data->perf_ctrls.desired_perf) 375 return ret; 376 377 cpu_data->perf_ctrls.desired_perf = desired_perf; 378 freqs.old = policy->cur; 379 freqs.new = target_freq; 380 381 cpufreq_freq_transition_begin(policy, &freqs); 382 ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls); 383 cpufreq_freq_transition_end(policy, &freqs, ret != 0); 384 385 if (ret) 386 pr_debug("Failed to set target on CPU:%d. ret:%d\n", 387 cpu, ret); 388 389 return ret; 390 } 391 392 static int cppc_verify_policy(struct cpufreq_policy_data *policy) 393 { 394 cpufreq_verify_within_cpu_limits(policy); 395 return 0; 396 } 397 398 /* 399 * The PCC subspace describes the rate at which platform can accept commands 400 * on the shared PCC channel (including READs which do not count towards freq 401 * transition requests), so ideally we need to use the PCC values as a fallback 402 * if we don't have a platform specific transition_delay_us 403 */ 404 #ifdef CONFIG_ARM64 405 #include <asm/cputype.h> 406 407 static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu) 408 { 409 unsigned long implementor = read_cpuid_implementor(); 410 unsigned long part_num = read_cpuid_part_number(); 411 412 switch (implementor) { 413 case ARM_CPU_IMP_QCOM: 414 switch (part_num) { 415 case QCOM_CPU_PART_FALKOR_V1: 416 case QCOM_CPU_PART_FALKOR: 417 return 10000; 418 } 419 } 420 return cppc_get_transition_latency(cpu) / NSEC_PER_USEC; 421 } 422 423 #else 424 425 static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu) 426 { 427 return cppc_get_transition_latency(cpu) / NSEC_PER_USEC; 428 } 429 #endif 430 431 432 static struct cppc_cpudata *cppc_cpufreq_get_cpu_data(unsigned int cpu) 433 { 434 struct cppc_cpudata *cpu_data; 435 int ret; 436 437 cpu_data = kzalloc(sizeof(struct cppc_cpudata), GFP_KERNEL); 438 if (!cpu_data) 439 goto out; 440 441 if (!zalloc_cpumask_var(&cpu_data->shared_cpu_map, GFP_KERNEL)) 442 goto free_cpu; 443 444 ret = acpi_get_psd_map(cpu, cpu_data); 445 if (ret) { 446 pr_debug("Err parsing CPU%d PSD data: ret:%d\n", cpu, ret); 447 goto free_mask; 448 } 449 450 ret = cppc_get_perf_caps(cpu, &cpu_data->perf_caps); 451 if (ret) { 452 pr_debug("Err reading CPU%d perf caps: ret:%d\n", cpu, ret); 453 goto free_mask; 454 } 455 456 /* Convert the lowest and nominal freq from MHz to KHz */ 457 cpu_data->perf_caps.lowest_freq *= 1000; 458 cpu_data->perf_caps.nominal_freq *= 1000; 459 460 list_add(&cpu_data->node, &cpu_data_list); 461 462 return cpu_data; 463 464 free_mask: 465 free_cpumask_var(cpu_data->shared_cpu_map); 466 free_cpu: 467 kfree(cpu_data); 468 out: 469 return NULL; 470 } 471 472 static void cppc_cpufreq_put_cpu_data(struct cpufreq_policy *policy) 473 { 474 struct cppc_cpudata *cpu_data = policy->driver_data; 475 476 list_del(&cpu_data->node); 477 free_cpumask_var(cpu_data->shared_cpu_map); 478 kfree(cpu_data); 479 policy->driver_data = NULL; 480 } 481 482 static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy) 483 { 484 unsigned int cpu = policy->cpu; 485 struct cppc_cpudata *cpu_data; 486 struct cppc_perf_caps *caps; 487 int ret; 488 489 cpu_data = cppc_cpufreq_get_cpu_data(cpu); 490 if (!cpu_data) { 491 pr_err("Error in acquiring _CPC/_PSD data for CPU%d.\n", cpu); 492 return -ENODEV; 493 } 494 caps = &cpu_data->perf_caps; 495 policy->driver_data = cpu_data; 496 497 /* 498 * Set min to lowest nonlinear perf to avoid any efficiency penalty (see 499 * Section 8.4.7.1.1.5 of ACPI 6.1 spec) 500 */ 501 policy->min = cppc_cpufreq_perf_to_khz(cpu_data, 502 caps->lowest_nonlinear_perf); 503 policy->max = cppc_cpufreq_perf_to_khz(cpu_data, 504 caps->nominal_perf); 505 506 /* 507 * Set cpuinfo.min_freq to Lowest to make the full range of performance 508 * available if userspace wants to use any perf between lowest & lowest 509 * nonlinear perf 510 */ 511 policy->cpuinfo.min_freq = cppc_cpufreq_perf_to_khz(cpu_data, 512 caps->lowest_perf); 513 policy->cpuinfo.max_freq = cppc_cpufreq_perf_to_khz(cpu_data, 514 caps->nominal_perf); 515 516 policy->transition_delay_us = cppc_cpufreq_get_transition_delay_us(cpu); 517 policy->shared_type = cpu_data->shared_type; 518 519 switch (policy->shared_type) { 520 case CPUFREQ_SHARED_TYPE_HW: 521 case CPUFREQ_SHARED_TYPE_NONE: 522 /* Nothing to be done - we'll have a policy for each CPU */ 523 break; 524 case CPUFREQ_SHARED_TYPE_ANY: 525 /* 526 * All CPUs in the domain will share a policy and all cpufreq 527 * operations will use a single cppc_cpudata structure stored 528 * in policy->driver_data. 529 */ 530 cpumask_copy(policy->cpus, cpu_data->shared_cpu_map); 531 break; 532 default: 533 pr_debug("Unsupported CPU co-ord type: %d\n", 534 policy->shared_type); 535 ret = -EFAULT; 536 goto out; 537 } 538 539 /* 540 * If 'highest_perf' is greater than 'nominal_perf', we assume CPU Boost 541 * is supported. 542 */ 543 if (caps->highest_perf > caps->nominal_perf) 544 boost_supported = true; 545 546 /* Set policy->cur to max now. The governors will adjust later. */ 547 policy->cur = cppc_cpufreq_perf_to_khz(cpu_data, caps->highest_perf); 548 cpu_data->perf_ctrls.desired_perf = caps->highest_perf; 549 550 ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls); 551 if (ret) { 552 pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n", 553 caps->highest_perf, cpu, ret); 554 goto out; 555 } 556 557 cppc_cpufreq_cpu_fie_init(policy); 558 return 0; 559 560 out: 561 cppc_cpufreq_put_cpu_data(policy); 562 return ret; 563 } 564 565 static int cppc_cpufreq_cpu_exit(struct cpufreq_policy *policy) 566 { 567 struct cppc_cpudata *cpu_data = policy->driver_data; 568 struct cppc_perf_caps *caps = &cpu_data->perf_caps; 569 unsigned int cpu = policy->cpu; 570 int ret; 571 572 cppc_cpufreq_cpu_fie_exit(policy); 573 574 cpu_data->perf_ctrls.desired_perf = caps->lowest_perf; 575 576 ret = cppc_set_perf(cpu, &cpu_data->perf_ctrls); 577 if (ret) 578 pr_debug("Err setting perf value:%d on CPU:%d. ret:%d\n", 579 caps->lowest_perf, cpu, ret); 580 581 cppc_cpufreq_put_cpu_data(policy); 582 return 0; 583 } 584 585 static inline u64 get_delta(u64 t1, u64 t0) 586 { 587 if (t1 > t0 || t0 > ~(u32)0) 588 return t1 - t0; 589 590 return (u32)t1 - (u32)t0; 591 } 592 593 static int cppc_perf_from_fbctrs(struct cppc_cpudata *cpu_data, 594 struct cppc_perf_fb_ctrs *fb_ctrs_t0, 595 struct cppc_perf_fb_ctrs *fb_ctrs_t1) 596 { 597 u64 delta_reference, delta_delivered; 598 u64 reference_perf; 599 600 reference_perf = fb_ctrs_t0->reference_perf; 601 602 delta_reference = get_delta(fb_ctrs_t1->reference, 603 fb_ctrs_t0->reference); 604 delta_delivered = get_delta(fb_ctrs_t1->delivered, 605 fb_ctrs_t0->delivered); 606 607 /* Check to avoid divide-by zero and invalid delivered_perf */ 608 if (!delta_reference || !delta_delivered) 609 return cpu_data->perf_ctrls.desired_perf; 610 611 return (reference_perf * delta_delivered) / delta_reference; 612 } 613 614 static unsigned int cppc_cpufreq_get_rate(unsigned int cpu) 615 { 616 struct cppc_perf_fb_ctrs fb_ctrs_t0 = {0}, fb_ctrs_t1 = {0}; 617 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); 618 struct cppc_cpudata *cpu_data = policy->driver_data; 619 u64 delivered_perf; 620 int ret; 621 622 cpufreq_cpu_put(policy); 623 624 ret = cppc_get_perf_ctrs(cpu, &fb_ctrs_t0); 625 if (ret) 626 return ret; 627 628 udelay(2); /* 2usec delay between sampling */ 629 630 ret = cppc_get_perf_ctrs(cpu, &fb_ctrs_t1); 631 if (ret) 632 return ret; 633 634 delivered_perf = cppc_perf_from_fbctrs(cpu_data, &fb_ctrs_t0, 635 &fb_ctrs_t1); 636 637 return cppc_cpufreq_perf_to_khz(cpu_data, delivered_perf); 638 } 639 640 static int cppc_cpufreq_set_boost(struct cpufreq_policy *policy, int state) 641 { 642 struct cppc_cpudata *cpu_data = policy->driver_data; 643 struct cppc_perf_caps *caps = &cpu_data->perf_caps; 644 int ret; 645 646 if (!boost_supported) { 647 pr_err("BOOST not supported by CPU or firmware\n"); 648 return -EINVAL; 649 } 650 651 if (state) 652 policy->max = cppc_cpufreq_perf_to_khz(cpu_data, 653 caps->highest_perf); 654 else 655 policy->max = cppc_cpufreq_perf_to_khz(cpu_data, 656 caps->nominal_perf); 657 policy->cpuinfo.max_freq = policy->max; 658 659 ret = freq_qos_update_request(policy->max_freq_req, policy->max); 660 if (ret < 0) 661 return ret; 662 663 return 0; 664 } 665 666 static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf) 667 { 668 struct cppc_cpudata *cpu_data = policy->driver_data; 669 670 return cpufreq_show_cpus(cpu_data->shared_cpu_map, buf); 671 } 672 cpufreq_freq_attr_ro(freqdomain_cpus); 673 674 static struct freq_attr *cppc_cpufreq_attr[] = { 675 &freqdomain_cpus, 676 NULL, 677 }; 678 679 static struct cpufreq_driver cppc_cpufreq_driver = { 680 .flags = CPUFREQ_CONST_LOOPS, 681 .verify = cppc_verify_policy, 682 .target = cppc_cpufreq_set_target, 683 .get = cppc_cpufreq_get_rate, 684 .init = cppc_cpufreq_cpu_init, 685 .exit = cppc_cpufreq_cpu_exit, 686 .set_boost = cppc_cpufreq_set_boost, 687 .attr = cppc_cpufreq_attr, 688 .name = "cppc_cpufreq", 689 }; 690 691 /* 692 * HISI platform does not support delivered performance counter and 693 * reference performance counter. It can calculate the performance using the 694 * platform specific mechanism. We reuse the desired performance register to 695 * store the real performance calculated by the platform. 696 */ 697 static unsigned int hisi_cppc_cpufreq_get_rate(unsigned int cpu) 698 { 699 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); 700 struct cppc_cpudata *cpu_data = policy->driver_data; 701 u64 desired_perf; 702 int ret; 703 704 cpufreq_cpu_put(policy); 705 706 ret = cppc_get_desired_perf(cpu, &desired_perf); 707 if (ret < 0) 708 return -EIO; 709 710 return cppc_cpufreq_perf_to_khz(cpu_data, desired_perf); 711 } 712 713 static void cppc_check_hisi_workaround(void) 714 { 715 struct acpi_table_header *tbl; 716 acpi_status status = AE_OK; 717 int i; 718 719 status = acpi_get_table(ACPI_SIG_PCCT, 0, &tbl); 720 if (ACPI_FAILURE(status) || !tbl) 721 return; 722 723 for (i = 0; i < ARRAY_SIZE(wa_info); i++) { 724 if (!memcmp(wa_info[i].oem_id, tbl->oem_id, ACPI_OEM_ID_SIZE) && 725 !memcmp(wa_info[i].oem_table_id, tbl->oem_table_id, ACPI_OEM_TABLE_ID_SIZE) && 726 wa_info[i].oem_revision == tbl->oem_revision) { 727 /* Overwrite the get() callback */ 728 cppc_cpufreq_driver.get = hisi_cppc_cpufreq_get_rate; 729 break; 730 } 731 } 732 733 acpi_put_table(tbl); 734 } 735 736 static int __init cppc_cpufreq_init(void) 737 { 738 int ret; 739 740 if ((acpi_disabled) || !acpi_cpc_valid()) 741 return -ENODEV; 742 743 cppc_check_hisi_workaround(); 744 cppc_freq_invariance_init(); 745 746 ret = cpufreq_register_driver(&cppc_cpufreq_driver); 747 if (ret) 748 cppc_freq_invariance_exit(); 749 750 return ret; 751 } 752 753 static inline void free_cpu_data(void) 754 { 755 struct cppc_cpudata *iter, *tmp; 756 757 list_for_each_entry_safe(iter, tmp, &cpu_data_list, node) { 758 free_cpumask_var(iter->shared_cpu_map); 759 list_del(&iter->node); 760 kfree(iter); 761 } 762 763 } 764 765 static void __exit cppc_cpufreq_exit(void) 766 { 767 cpufreq_unregister_driver(&cppc_cpufreq_driver); 768 cppc_freq_invariance_exit(); 769 770 free_cpu_data(); 771 } 772 773 module_exit(cppc_cpufreq_exit); 774 MODULE_AUTHOR("Ashwin Chaugule"); 775 MODULE_DESCRIPTION("CPUFreq driver based on the ACPI CPPC v5.0+ spec"); 776 MODULE_LICENSE("GPL"); 777 778 late_initcall(cppc_cpufreq_init); 779 780 static const struct acpi_device_id cppc_acpi_ids[] __used = { 781 {ACPI_PROCESSOR_DEVICE_HID, }, 782 {} 783 }; 784 785 MODULE_DEVICE_TABLE(acpi, cppc_acpi_ids); 786