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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * acpi-cpufreq.c - ACPI Processor P-States Driver
4 *
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * Copyright (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
8 * Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
9 */
10
11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/smp.h>
17#include <linux/sched.h>
18#include <linux/cpufreq.h>
19#include <linux/compiler.h>
20#include <linux/dmi.h>
21#include <linux/slab.h>
22
23#include <linux/acpi.h>
24#include <linux/io.h>
25#include <linux/delay.h>
26#include <linux/uaccess.h>
27
28#include <acpi/processor.h>
29
30#include <asm/msr.h>
31#include <asm/processor.h>
32#include <asm/cpufeature.h>
33#include <asm/cpu_device_id.h>
34
35MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
36MODULE_DESCRIPTION("ACPI Processor P-States Driver");
37MODULE_LICENSE("GPL");
38
39enum {
40 UNDEFINED_CAPABLE = 0,
41 SYSTEM_INTEL_MSR_CAPABLE,
42 SYSTEM_AMD_MSR_CAPABLE,
43 SYSTEM_IO_CAPABLE,
44};
45
46#define INTEL_MSR_RANGE (0xffff)
47#define AMD_MSR_RANGE (0x7)
48#define HYGON_MSR_RANGE (0x7)
49
50#define MSR_K7_HWCR_CPB_DIS (1ULL << 25)
51
52struct acpi_cpufreq_data {
53 unsigned int resume;
54 unsigned int cpu_feature;
55 unsigned int acpi_perf_cpu;
56 cpumask_var_t freqdomain_cpus;
57 void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);
58 u32 (*cpu_freq_read)(struct acpi_pct_register *reg);
59};
60
61/* acpi_perf_data is a pointer to percpu data. */
62static struct acpi_processor_performance __percpu *acpi_perf_data;
63
64static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
65{
66 return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
67}
68
69static struct cpufreq_driver acpi_cpufreq_driver;
70
71static unsigned int acpi_pstate_strict;
72
73static bool boost_state(unsigned int cpu)
74{
75 u32 lo, hi;
76 u64 msr;
77
78 switch (boot_cpu_data.x86_vendor) {
79 case X86_VENDOR_INTEL:
80 rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
81 msr = lo | ((u64)hi << 32);
82 return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
83 case X86_VENDOR_HYGON:
84 case X86_VENDOR_AMD:
85 rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
86 msr = lo | ((u64)hi << 32);
87 return !(msr & MSR_K7_HWCR_CPB_DIS);
88 }
89 return false;
90}
91
92static int boost_set_msr(bool enable)
93{
94 u32 msr_addr;
95 u64 msr_mask, val;
96
97 switch (boot_cpu_data.x86_vendor) {
98 case X86_VENDOR_INTEL:
99 msr_addr = MSR_IA32_MISC_ENABLE;
100 msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
101 break;
102 case X86_VENDOR_HYGON:
103 case X86_VENDOR_AMD:
104 msr_addr = MSR_K7_HWCR;
105 msr_mask = MSR_K7_HWCR_CPB_DIS;
106 break;
107 default:
108 return -EINVAL;
109 }
110
111 rdmsrl(msr_addr, val);
112
113 if (enable)
114 val &= ~msr_mask;
115 else
116 val |= msr_mask;
117
118 wrmsrl(msr_addr, val);
119 return 0;
120}
121
122static void boost_set_msr_each(void *p_en)
123{
124 bool enable = (bool) p_en;
125
126 boost_set_msr(enable);
127}
128
129static int set_boost(struct cpufreq_policy *policy, int val)
130{
131 on_each_cpu_mask(policy->cpus, boost_set_msr_each,
132 (void *)(long)val, 1);
133 pr_debug("CPU %*pbl: Core Boosting %sabled.\n",
134 cpumask_pr_args(policy->cpus), val ? "en" : "dis");
135
136 return 0;
137}
138
139static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
140{
141 struct acpi_cpufreq_data *data = policy->driver_data;
142
143 if (unlikely(!data))
144 return -ENODEV;
145
146 return cpufreq_show_cpus(data->freqdomain_cpus, buf);
147}
148
149cpufreq_freq_attr_ro(freqdomain_cpus);
150
151#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
152static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
153 size_t count)
154{
155 int ret;
156 unsigned int val = 0;
157
158 if (!acpi_cpufreq_driver.set_boost)
159 return -EINVAL;
160
161 ret = kstrtouint(buf, 10, &val);
162 if (ret || val > 1)
163 return -EINVAL;
164
165 get_online_cpus();
166 set_boost(policy, val);
167 put_online_cpus();
168
169 return count;
170}
171
172static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
173{
174 return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
175}
176
177cpufreq_freq_attr_rw(cpb);
178#endif
179
180static int check_est_cpu(unsigned int cpuid)
181{
182 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
183
184 return cpu_has(cpu, X86_FEATURE_EST);
185}
186
187static int check_amd_hwpstate_cpu(unsigned int cpuid)
188{
189 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
190
191 return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
192}
193
194static unsigned extract_io(struct cpufreq_policy *policy, u32 value)
195{
196 struct acpi_cpufreq_data *data = policy->driver_data;
197 struct acpi_processor_performance *perf;
198 int i;
199
200 perf = to_perf_data(data);
201
202 for (i = 0; i < perf->state_count; i++) {
203 if (value == perf->states[i].status)
204 return policy->freq_table[i].frequency;
205 }
206 return 0;
207}
208
209static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
210{
211 struct acpi_cpufreq_data *data = policy->driver_data;
212 struct cpufreq_frequency_table *pos;
213 struct acpi_processor_performance *perf;
214
215 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
216 msr &= AMD_MSR_RANGE;
217 else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
218 msr &= HYGON_MSR_RANGE;
219 else
220 msr &= INTEL_MSR_RANGE;
221
222 perf = to_perf_data(data);
223
224 cpufreq_for_each_entry(pos, policy->freq_table)
225 if (msr == perf->states[pos->driver_data].status)
226 return pos->frequency;
227 return policy->freq_table[0].frequency;
228}
229
230static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
231{
232 struct acpi_cpufreq_data *data = policy->driver_data;
233
234 switch (data->cpu_feature) {
235 case SYSTEM_INTEL_MSR_CAPABLE:
236 case SYSTEM_AMD_MSR_CAPABLE:
237 return extract_msr(policy, val);
238 case SYSTEM_IO_CAPABLE:
239 return extract_io(policy, val);
240 default:
241 return 0;
242 }
243}
244
245static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
246{
247 u32 val, dummy __always_unused;
248
249 rdmsr(MSR_IA32_PERF_CTL, val, dummy);
250 return val;
251}
252
253static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
254{
255 u32 lo, hi;
256
257 rdmsr(MSR_IA32_PERF_CTL, lo, hi);
258 lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
259 wrmsr(MSR_IA32_PERF_CTL, lo, hi);
260}
261
262static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
263{
264 u32 val, dummy __always_unused;
265
266 rdmsr(MSR_AMD_PERF_CTL, val, dummy);
267 return val;
268}
269
270static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
271{
272 wrmsr(MSR_AMD_PERF_CTL, val, 0);
273}
274
275static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
276{
277 u32 val;
278
279 acpi_os_read_port(reg->address, &val, reg->bit_width);
280 return val;
281}
282
283static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
284{
285 acpi_os_write_port(reg->address, val, reg->bit_width);
286}
287
288struct drv_cmd {
289 struct acpi_pct_register *reg;
290 u32 val;
291 union {
292 void (*write)(struct acpi_pct_register *reg, u32 val);
293 u32 (*read)(struct acpi_pct_register *reg);
294 } func;
295};
296
297/* Called via smp_call_function_single(), on the target CPU */
298static void do_drv_read(void *_cmd)
299{
300 struct drv_cmd *cmd = _cmd;
301
302 cmd->val = cmd->func.read(cmd->reg);
303}
304
305static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
306{
307 struct acpi_processor_performance *perf = to_perf_data(data);
308 struct drv_cmd cmd = {
309 .reg = &perf->control_register,
310 .func.read = data->cpu_freq_read,
311 };
312 int err;
313
314 err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
315 WARN_ON_ONCE(err); /* smp_call_function_any() was buggy? */
316 return cmd.val;
317}
318
319/* Called via smp_call_function_many(), on the target CPUs */
320static void do_drv_write(void *_cmd)
321{
322 struct drv_cmd *cmd = _cmd;
323
324 cmd->func.write(cmd->reg, cmd->val);
325}
326
327static void drv_write(struct acpi_cpufreq_data *data,
328 const struct cpumask *mask, u32 val)
329{
330 struct acpi_processor_performance *perf = to_perf_data(data);
331 struct drv_cmd cmd = {
332 .reg = &perf->control_register,
333 .val = val,
334 .func.write = data->cpu_freq_write,
335 };
336 int this_cpu;
337
338 this_cpu = get_cpu();
339 if (cpumask_test_cpu(this_cpu, mask))
340 do_drv_write(&cmd);
341
342 smp_call_function_many(mask, do_drv_write, &cmd, 1);
343 put_cpu();
344}
345
346static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
347{
348 u32 val;
349
350 if (unlikely(cpumask_empty(mask)))
351 return 0;
352
353 val = drv_read(data, mask);
354
355 pr_debug("%s = %u\n", __func__, val);
356
357 return val;
358}
359
360static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
361{
362 struct acpi_cpufreq_data *data;
363 struct cpufreq_policy *policy;
364 unsigned int freq;
365 unsigned int cached_freq;
366
367 pr_debug("%s (%d)\n", __func__, cpu);
368
369 policy = cpufreq_cpu_get_raw(cpu);
370 if (unlikely(!policy))
371 return 0;
372
373 data = policy->driver_data;
374 if (unlikely(!data || !policy->freq_table))
375 return 0;
376
377 cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;
378 freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));
379 if (freq != cached_freq) {
380 /*
381 * The dreaded BIOS frequency change behind our back.
382 * Force set the frequency on next target call.
383 */
384 data->resume = 1;
385 }
386
387 pr_debug("cur freq = %u\n", freq);
388
389 return freq;
390}
391
392static unsigned int check_freqs(struct cpufreq_policy *policy,
393 const struct cpumask *mask, unsigned int freq)
394{
395 struct acpi_cpufreq_data *data = policy->driver_data;
396 unsigned int cur_freq;
397 unsigned int i;
398
399 for (i = 0; i < 100; i++) {
400 cur_freq = extract_freq(policy, get_cur_val(mask, data));
401 if (cur_freq == freq)
402 return 1;
403 udelay(10);
404 }
405 return 0;
406}
407
408static int acpi_cpufreq_target(struct cpufreq_policy *policy,
409 unsigned int index)
410{
411 struct acpi_cpufreq_data *data = policy->driver_data;
412 struct acpi_processor_performance *perf;
413 const struct cpumask *mask;
414 unsigned int next_perf_state = 0; /* Index into perf table */
415 int result = 0;
416
417 if (unlikely(!data)) {
418 return -ENODEV;
419 }
420
421 perf = to_perf_data(data);
422 next_perf_state = policy->freq_table[index].driver_data;
423 if (perf->state == next_perf_state) {
424 if (unlikely(data->resume)) {
425 pr_debug("Called after resume, resetting to P%d\n",
426 next_perf_state);
427 data->resume = 0;
428 } else {
429 pr_debug("Already at target state (P%d)\n",
430 next_perf_state);
431 return 0;
432 }
433 }
434
435 /*
436 * The core won't allow CPUs to go away until the governor has been
437 * stopped, so we can rely on the stability of policy->cpus.
438 */
439 mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
440 cpumask_of(policy->cpu) : policy->cpus;
441
442 drv_write(data, mask, perf->states[next_perf_state].control);
443
444 if (acpi_pstate_strict) {
445 if (!check_freqs(policy, mask,
446 policy->freq_table[index].frequency)) {
447 pr_debug("%s (%d)\n", __func__, policy->cpu);
448 result = -EAGAIN;
449 }
450 }
451
452 if (!result)
453 perf->state = next_perf_state;
454
455 return result;
456}
457
458static unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
459 unsigned int target_freq)
460{
461 struct acpi_cpufreq_data *data = policy->driver_data;
462 struct acpi_processor_performance *perf;
463 struct cpufreq_frequency_table *entry;
464 unsigned int next_perf_state, next_freq, index;
465
466 /*
467 * Find the closest frequency above target_freq.
468 */
469 if (policy->cached_target_freq == target_freq)
470 index = policy->cached_resolved_idx;
471 else
472 index = cpufreq_table_find_index_dl(policy, target_freq);
473
474 entry = &policy->freq_table[index];
475 next_freq = entry->frequency;
476 next_perf_state = entry->driver_data;
477
478 perf = to_perf_data(data);
479 if (perf->state == next_perf_state) {
480 if (unlikely(data->resume))
481 data->resume = 0;
482 else
483 return next_freq;
484 }
485
486 data->cpu_freq_write(&perf->control_register,
487 perf->states[next_perf_state].control);
488 perf->state = next_perf_state;
489 return next_freq;
490}
491
492static unsigned long
493acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
494{
495 struct acpi_processor_performance *perf;
496
497 perf = to_perf_data(data);
498 if (cpu_khz) {
499 /* search the closest match to cpu_khz */
500 unsigned int i;
501 unsigned long freq;
502 unsigned long freqn = perf->states[0].core_frequency * 1000;
503
504 for (i = 0; i < (perf->state_count-1); i++) {
505 freq = freqn;
506 freqn = perf->states[i+1].core_frequency * 1000;
507 if ((2 * cpu_khz) > (freqn + freq)) {
508 perf->state = i;
509 return freq;
510 }
511 }
512 perf->state = perf->state_count-1;
513 return freqn;
514 } else {
515 /* assume CPU is at P0... */
516 perf->state = 0;
517 return perf->states[0].core_frequency * 1000;
518 }
519}
520
521static void free_acpi_perf_data(void)
522{
523 unsigned int i;
524
525 /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
526 for_each_possible_cpu(i)
527 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
528 ->shared_cpu_map);
529 free_percpu(acpi_perf_data);
530}
531
532static int cpufreq_boost_online(unsigned int cpu)
533{
534 /*
535 * On the CPU_UP path we simply keep the boost-disable flag
536 * in sync with the current global state.
537 */
538 return boost_set_msr(acpi_cpufreq_driver.boost_enabled);
539}
540
541static int cpufreq_boost_down_prep(unsigned int cpu)
542{
543 /*
544 * Clear the boost-disable bit on the CPU_DOWN path so that
545 * this cpu cannot block the remaining ones from boosting.
546 */
547 return boost_set_msr(1);
548}
549
550/*
551 * acpi_cpufreq_early_init - initialize ACPI P-States library
552 *
553 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
554 * in order to determine correct frequency and voltage pairings. We can
555 * do _PDC and _PSD and find out the processor dependency for the
556 * actual init that will happen later...
557 */
558static int __init acpi_cpufreq_early_init(void)
559{
560 unsigned int i;
561 pr_debug("%s\n", __func__);
562
563 acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
564 if (!acpi_perf_data) {
565 pr_debug("Memory allocation error for acpi_perf_data.\n");
566 return -ENOMEM;
567 }
568 for_each_possible_cpu(i) {
569 if (!zalloc_cpumask_var_node(
570 &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
571 GFP_KERNEL, cpu_to_node(i))) {
572
573 /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
574 free_acpi_perf_data();
575 return -ENOMEM;
576 }
577 }
578
579 /* Do initialization in ACPI core */
580 acpi_processor_preregister_performance(acpi_perf_data);
581 return 0;
582}
583
584#ifdef CONFIG_SMP
585/*
586 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
587 * or do it in BIOS firmware and won't inform about it to OS. If not
588 * detected, this has a side effect of making CPU run at a different speed
589 * than OS intended it to run at. Detect it and handle it cleanly.
590 */
591static int bios_with_sw_any_bug;
592
593static int sw_any_bug_found(const struct dmi_system_id *d)
594{
595 bios_with_sw_any_bug = 1;
596 return 0;
597}
598
599static const struct dmi_system_id sw_any_bug_dmi_table[] = {
600 {
601 .callback = sw_any_bug_found,
602 .ident = "Supermicro Server X6DLP",
603 .matches = {
604 DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
605 DMI_MATCH(DMI_BIOS_VERSION, "080010"),
606 DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
607 },
608 },
609 { }
610};
611
612static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
613{
614 /* Intel Xeon Processor 7100 Series Specification Update
615 * https://www.intel.com/Assets/PDF/specupdate/314554.pdf
616 * AL30: A Machine Check Exception (MCE) Occurring during an
617 * Enhanced Intel SpeedStep Technology Ratio Change May Cause
618 * Both Processor Cores to Lock Up. */
619 if (c->x86_vendor == X86_VENDOR_INTEL) {
620 if ((c->x86 == 15) &&
621 (c->x86_model == 6) &&
622 (c->x86_stepping == 8)) {
623 pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");
624 return -ENODEV;
625 }
626 }
627 return 0;
628}
629#endif
630
631static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
632{
633 unsigned int i;
634 unsigned int valid_states = 0;
635 unsigned int cpu = policy->cpu;
636 struct acpi_cpufreq_data *data;
637 unsigned int result = 0;
638 struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
639 struct acpi_processor_performance *perf;
640 struct cpufreq_frequency_table *freq_table;
641#ifdef CONFIG_SMP
642 static int blacklisted;
643#endif
644
645 pr_debug("%s\n", __func__);
646
647#ifdef CONFIG_SMP
648 if (blacklisted)
649 return blacklisted;
650 blacklisted = acpi_cpufreq_blacklist(c);
651 if (blacklisted)
652 return blacklisted;
653#endif
654
655 data = kzalloc(sizeof(*data), GFP_KERNEL);
656 if (!data)
657 return -ENOMEM;
658
659 if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
660 result = -ENOMEM;
661 goto err_free;
662 }
663
664 perf = per_cpu_ptr(acpi_perf_data, cpu);
665 data->acpi_perf_cpu = cpu;
666 policy->driver_data = data;
667
668 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
669 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
670
671 result = acpi_processor_register_performance(perf, cpu);
672 if (result)
673 goto err_free_mask;
674
675 policy->shared_type = perf->shared_type;
676
677 /*
678 * Will let policy->cpus know about dependency only when software
679 * coordination is required.
680 */
681 if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
682 policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
683 cpumask_copy(policy->cpus, perf->shared_cpu_map);
684 }
685 cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
686
687#ifdef CONFIG_SMP
688 dmi_check_system(sw_any_bug_dmi_table);
689 if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
690 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
691 cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
692 }
693
694 if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
695 cpumask_clear(policy->cpus);
696 cpumask_set_cpu(cpu, policy->cpus);
697 cpumask_copy(data->freqdomain_cpus,
698 topology_sibling_cpumask(cpu));
699 policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
700 pr_info_once("overriding BIOS provided _PSD data\n");
701 }
702#endif
703
704 /* capability check */
705 if (perf->state_count <= 1) {
706 pr_debug("No P-States\n");
707 result = -ENODEV;
708 goto err_unreg;
709 }
710
711 if (perf->control_register.space_id != perf->status_register.space_id) {
712 result = -ENODEV;
713 goto err_unreg;
714 }
715
716 switch (perf->control_register.space_id) {
717 case ACPI_ADR_SPACE_SYSTEM_IO:
718 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
719 boot_cpu_data.x86 == 0xf) {
720 pr_debug("AMD K8 systems must use native drivers.\n");
721 result = -ENODEV;
722 goto err_unreg;
723 }
724 pr_debug("SYSTEM IO addr space\n");
725 data->cpu_feature = SYSTEM_IO_CAPABLE;
726 data->cpu_freq_read = cpu_freq_read_io;
727 data->cpu_freq_write = cpu_freq_write_io;
728 break;
729 case ACPI_ADR_SPACE_FIXED_HARDWARE:
730 pr_debug("HARDWARE addr space\n");
731 if (check_est_cpu(cpu)) {
732 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
733 data->cpu_freq_read = cpu_freq_read_intel;
734 data->cpu_freq_write = cpu_freq_write_intel;
735 break;
736 }
737 if (check_amd_hwpstate_cpu(cpu)) {
738 data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
739 data->cpu_freq_read = cpu_freq_read_amd;
740 data->cpu_freq_write = cpu_freq_write_amd;
741 break;
742 }
743 result = -ENODEV;
744 goto err_unreg;
745 default:
746 pr_debug("Unknown addr space %d\n",
747 (u32) (perf->control_register.space_id));
748 result = -ENODEV;
749 goto err_unreg;
750 }
751
752 freq_table = kcalloc(perf->state_count + 1, sizeof(*freq_table),
753 GFP_KERNEL);
754 if (!freq_table) {
755 result = -ENOMEM;
756 goto err_unreg;
757 }
758
759 /* detect transition latency */
760 policy->cpuinfo.transition_latency = 0;
761 for (i = 0; i < perf->state_count; i++) {
762 if ((perf->states[i].transition_latency * 1000) >
763 policy->cpuinfo.transition_latency)
764 policy->cpuinfo.transition_latency =
765 perf->states[i].transition_latency * 1000;
766 }
767
768 /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
769 if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
770 policy->cpuinfo.transition_latency > 20 * 1000) {
771 policy->cpuinfo.transition_latency = 20 * 1000;
772 pr_info_once("P-state transition latency capped at 20 uS\n");
773 }
774
775 /* table init */
776 for (i = 0; i < perf->state_count; i++) {
777 if (i > 0 && perf->states[i].core_frequency >=
778 freq_table[valid_states-1].frequency / 1000)
779 continue;
780
781 freq_table[valid_states].driver_data = i;
782 freq_table[valid_states].frequency =
783 perf->states[i].core_frequency * 1000;
784 valid_states++;
785 }
786 freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
787 policy->freq_table = freq_table;
788 perf->state = 0;
789
790 switch (perf->control_register.space_id) {
791 case ACPI_ADR_SPACE_SYSTEM_IO:
792 /*
793 * The core will not set policy->cur, because
794 * cpufreq_driver->get is NULL, so we need to set it here.
795 * However, we have to guess it, because the current speed is
796 * unknown and not detectable via IO ports.
797 */
798 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
799 break;
800 case ACPI_ADR_SPACE_FIXED_HARDWARE:
801 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
802 break;
803 default:
804 break;
805 }
806
807 /* notify BIOS that we exist */
808 acpi_processor_notify_smm(THIS_MODULE);
809
810 pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
811 for (i = 0; i < perf->state_count; i++)
812 pr_debug(" %cP%d: %d MHz, %d mW, %d uS\n",
813 (i == perf->state ? '*' : ' '), i,
814 (u32) perf->states[i].core_frequency,
815 (u32) perf->states[i].power,
816 (u32) perf->states[i].transition_latency);
817
818 /*
819 * the first call to ->target() should result in us actually
820 * writing something to the appropriate registers.
821 */
822 data->resume = 1;
823
824 policy->fast_switch_possible = !acpi_pstate_strict &&
825 !(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);
826
827 return result;
828
829err_unreg:
830 acpi_processor_unregister_performance(cpu);
831err_free_mask:
832 free_cpumask_var(data->freqdomain_cpus);
833err_free:
834 kfree(data);
835 policy->driver_data = NULL;
836
837 return result;
838}
839
840static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
841{
842 struct acpi_cpufreq_data *data = policy->driver_data;
843
844 pr_debug("%s\n", __func__);
845
846 policy->fast_switch_possible = false;
847 policy->driver_data = NULL;
848 acpi_processor_unregister_performance(data->acpi_perf_cpu);
849 free_cpumask_var(data->freqdomain_cpus);
850 kfree(policy->freq_table);
851 kfree(data);
852
853 return 0;
854}
855
856static void acpi_cpufreq_cpu_ready(struct cpufreq_policy *policy)
857{
858 struct acpi_processor_performance *perf = per_cpu_ptr(acpi_perf_data,
859 policy->cpu);
860
861 if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
862 pr_warn(FW_WARN "P-state 0 is not max freq\n");
863}
864
865static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
866{
867 struct acpi_cpufreq_data *data = policy->driver_data;
868
869 pr_debug("%s\n", __func__);
870
871 data->resume = 1;
872
873 return 0;
874}
875
876static struct freq_attr *acpi_cpufreq_attr[] = {
877 &cpufreq_freq_attr_scaling_available_freqs,
878 &freqdomain_cpus,
879#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
880 &cpb,
881#endif
882 NULL,
883};
884
885static struct cpufreq_driver acpi_cpufreq_driver = {
886 .verify = cpufreq_generic_frequency_table_verify,
887 .target_index = acpi_cpufreq_target,
888 .fast_switch = acpi_cpufreq_fast_switch,
889 .bios_limit = acpi_processor_get_bios_limit,
890 .init = acpi_cpufreq_cpu_init,
891 .exit = acpi_cpufreq_cpu_exit,
892 .ready = acpi_cpufreq_cpu_ready,
893 .resume = acpi_cpufreq_resume,
894 .name = "acpi-cpufreq",
895 .attr = acpi_cpufreq_attr,
896};
897
898static enum cpuhp_state acpi_cpufreq_online;
899
900static void __init acpi_cpufreq_boost_init(void)
901{
902 int ret;
903
904 if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA))) {
905 pr_debug("Boost capabilities not present in the processor\n");
906 return;
907 }
908
909 acpi_cpufreq_driver.set_boost = set_boost;
910 acpi_cpufreq_driver.boost_enabled = boost_state(0);
911
912 /*
913 * This calls the online callback on all online cpu and forces all
914 * MSRs to the same value.
915 */
916 ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "cpufreq/acpi:online",
917 cpufreq_boost_online, cpufreq_boost_down_prep);
918 if (ret < 0) {
919 pr_err("acpi_cpufreq: failed to register hotplug callbacks\n");
920 return;
921 }
922 acpi_cpufreq_online = ret;
923}
924
925static void acpi_cpufreq_boost_exit(void)
926{
927 if (acpi_cpufreq_online > 0)
928 cpuhp_remove_state_nocalls(acpi_cpufreq_online);
929}
930
931static int __init acpi_cpufreq_init(void)
932{
933 int ret;
934
935 if (acpi_disabled)
936 return -ENODEV;
937
938 /* don't keep reloading if cpufreq_driver exists */
939 if (cpufreq_get_current_driver())
940 return -EEXIST;
941
942 pr_debug("%s\n", __func__);
943
944 ret = acpi_cpufreq_early_init();
945 if (ret)
946 return ret;
947
948#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
949 /* this is a sysfs file with a strange name and an even stranger
950 * semantic - per CPU instantiation, but system global effect.
951 * Lets enable it only on AMD CPUs for compatibility reasons and
952 * only if configured. This is considered legacy code, which
953 * will probably be removed at some point in the future.
954 */
955 if (!check_amd_hwpstate_cpu(0)) {
956 struct freq_attr **attr;
957
958 pr_debug("CPB unsupported, do not expose it\n");
959
960 for (attr = acpi_cpufreq_attr; *attr; attr++)
961 if (*attr == &cpb) {
962 *attr = NULL;
963 break;
964 }
965 }
966#endif
967 acpi_cpufreq_boost_init();
968
969 ret = cpufreq_register_driver(&acpi_cpufreq_driver);
970 if (ret) {
971 free_acpi_perf_data();
972 acpi_cpufreq_boost_exit();
973 }
974 return ret;
975}
976
977static void __exit acpi_cpufreq_exit(void)
978{
979 pr_debug("%s\n", __func__);
980
981 acpi_cpufreq_boost_exit();
982
983 cpufreq_unregister_driver(&acpi_cpufreq_driver);
984
985 free_acpi_perf_data();
986}
987
988module_param(acpi_pstate_strict, uint, 0644);
989MODULE_PARM_DESC(acpi_pstate_strict,
990 "value 0 or non-zero. non-zero -> strict ACPI checks are "
991 "performed during frequency changes.");
992
993late_initcall(acpi_cpufreq_init);
994module_exit(acpi_cpufreq_exit);
995
996static const struct x86_cpu_id __maybe_unused acpi_cpufreq_ids[] = {
997 X86_MATCH_FEATURE(X86_FEATURE_ACPI, NULL),
998 X86_MATCH_FEATURE(X86_FEATURE_HW_PSTATE, NULL),
999 {}
1000};
1001MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1002
1003static const struct acpi_device_id __maybe_unused processor_device_ids[] = {
1004 {ACPI_PROCESSOR_OBJECT_HID, },
1005 {ACPI_PROCESSOR_DEVICE_HID, },
1006 {},
1007};
1008MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1009
1010MODULE_ALIAS("acpi");
1/*
2 * acpi-cpufreq.c - ACPI Processor P-States Driver
3 *
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 * Copyright (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
7 * Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
8 *
9 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or (at
14 * your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful, but
17 * WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 * General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License along
22 * with this program; if not, write to the Free Software Foundation, Inc.,
23 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
24 *
25 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
26 */
27
28#include <linux/kernel.h>
29#include <linux/module.h>
30#include <linux/init.h>
31#include <linux/smp.h>
32#include <linux/sched.h>
33#include <linux/cpufreq.h>
34#include <linux/compiler.h>
35#include <linux/dmi.h>
36#include <linux/slab.h>
37
38#include <linux/acpi.h>
39#include <linux/io.h>
40#include <linux/delay.h>
41#include <linux/uaccess.h>
42
43#include <acpi/processor.h>
44
45#include <asm/msr.h>
46#include <asm/processor.h>
47#include <asm/cpufeature.h>
48#include "mperf.h"
49
50MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
51MODULE_DESCRIPTION("ACPI Processor P-States Driver");
52MODULE_LICENSE("GPL");
53
54enum {
55 UNDEFINED_CAPABLE = 0,
56 SYSTEM_INTEL_MSR_CAPABLE,
57 SYSTEM_IO_CAPABLE,
58};
59
60#define INTEL_MSR_RANGE (0xffff)
61
62struct acpi_cpufreq_data {
63 struct acpi_processor_performance *acpi_data;
64 struct cpufreq_frequency_table *freq_table;
65 unsigned int resume;
66 unsigned int cpu_feature;
67};
68
69static DEFINE_PER_CPU(struct acpi_cpufreq_data *, acfreq_data);
70
71/* acpi_perf_data is a pointer to percpu data. */
72static struct acpi_processor_performance __percpu *acpi_perf_data;
73
74static struct cpufreq_driver acpi_cpufreq_driver;
75
76static unsigned int acpi_pstate_strict;
77
78static int check_est_cpu(unsigned int cpuid)
79{
80 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
81
82 return cpu_has(cpu, X86_FEATURE_EST);
83}
84
85static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
86{
87 struct acpi_processor_performance *perf;
88 int i;
89
90 perf = data->acpi_data;
91
92 for (i = 0; i < perf->state_count; i++) {
93 if (value == perf->states[i].status)
94 return data->freq_table[i].frequency;
95 }
96 return 0;
97}
98
99static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
100{
101 int i;
102 struct acpi_processor_performance *perf;
103
104 msr &= INTEL_MSR_RANGE;
105 perf = data->acpi_data;
106
107 for (i = 0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
108 if (msr == perf->states[data->freq_table[i].index].status)
109 return data->freq_table[i].frequency;
110 }
111 return data->freq_table[0].frequency;
112}
113
114static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
115{
116 switch (data->cpu_feature) {
117 case SYSTEM_INTEL_MSR_CAPABLE:
118 return extract_msr(val, data);
119 case SYSTEM_IO_CAPABLE:
120 return extract_io(val, data);
121 default:
122 return 0;
123 }
124}
125
126struct msr_addr {
127 u32 reg;
128};
129
130struct io_addr {
131 u16 port;
132 u8 bit_width;
133};
134
135struct drv_cmd {
136 unsigned int type;
137 const struct cpumask *mask;
138 union {
139 struct msr_addr msr;
140 struct io_addr io;
141 } addr;
142 u32 val;
143};
144
145/* Called via smp_call_function_single(), on the target CPU */
146static void do_drv_read(void *_cmd)
147{
148 struct drv_cmd *cmd = _cmd;
149 u32 h;
150
151 switch (cmd->type) {
152 case SYSTEM_INTEL_MSR_CAPABLE:
153 rdmsr(cmd->addr.msr.reg, cmd->val, h);
154 break;
155 case SYSTEM_IO_CAPABLE:
156 acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
157 &cmd->val,
158 (u32)cmd->addr.io.bit_width);
159 break;
160 default:
161 break;
162 }
163}
164
165/* Called via smp_call_function_many(), on the target CPUs */
166static void do_drv_write(void *_cmd)
167{
168 struct drv_cmd *cmd = _cmd;
169 u32 lo, hi;
170
171 switch (cmd->type) {
172 case SYSTEM_INTEL_MSR_CAPABLE:
173 rdmsr(cmd->addr.msr.reg, lo, hi);
174 lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
175 wrmsr(cmd->addr.msr.reg, lo, hi);
176 break;
177 case SYSTEM_IO_CAPABLE:
178 acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
179 cmd->val,
180 (u32)cmd->addr.io.bit_width);
181 break;
182 default:
183 break;
184 }
185}
186
187static void drv_read(struct drv_cmd *cmd)
188{
189 int err;
190 cmd->val = 0;
191
192 err = smp_call_function_any(cmd->mask, do_drv_read, cmd, 1);
193 WARN_ON_ONCE(err); /* smp_call_function_any() was buggy? */
194}
195
196static void drv_write(struct drv_cmd *cmd)
197{
198 int this_cpu;
199
200 this_cpu = get_cpu();
201 if (cpumask_test_cpu(this_cpu, cmd->mask))
202 do_drv_write(cmd);
203 smp_call_function_many(cmd->mask, do_drv_write, cmd, 1);
204 put_cpu();
205}
206
207static u32 get_cur_val(const struct cpumask *mask)
208{
209 struct acpi_processor_performance *perf;
210 struct drv_cmd cmd;
211
212 if (unlikely(cpumask_empty(mask)))
213 return 0;
214
215 switch (per_cpu(acfreq_data, cpumask_first(mask))->cpu_feature) {
216 case SYSTEM_INTEL_MSR_CAPABLE:
217 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
218 cmd.addr.msr.reg = MSR_IA32_PERF_STATUS;
219 break;
220 case SYSTEM_IO_CAPABLE:
221 cmd.type = SYSTEM_IO_CAPABLE;
222 perf = per_cpu(acfreq_data, cpumask_first(mask))->acpi_data;
223 cmd.addr.io.port = perf->control_register.address;
224 cmd.addr.io.bit_width = perf->control_register.bit_width;
225 break;
226 default:
227 return 0;
228 }
229
230 cmd.mask = mask;
231 drv_read(&cmd);
232
233 pr_debug("get_cur_val = %u\n", cmd.val);
234
235 return cmd.val;
236}
237
238static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
239{
240 struct acpi_cpufreq_data *data = per_cpu(acfreq_data, cpu);
241 unsigned int freq;
242 unsigned int cached_freq;
243
244 pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
245
246 if (unlikely(data == NULL ||
247 data->acpi_data == NULL || data->freq_table == NULL)) {
248 return 0;
249 }
250
251 cached_freq = data->freq_table[data->acpi_data->state].frequency;
252 freq = extract_freq(get_cur_val(cpumask_of(cpu)), data);
253 if (freq != cached_freq) {
254 /*
255 * The dreaded BIOS frequency change behind our back.
256 * Force set the frequency on next target call.
257 */
258 data->resume = 1;
259 }
260
261 pr_debug("cur freq = %u\n", freq);
262
263 return freq;
264}
265
266static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq,
267 struct acpi_cpufreq_data *data)
268{
269 unsigned int cur_freq;
270 unsigned int i;
271
272 for (i = 0; i < 100; i++) {
273 cur_freq = extract_freq(get_cur_val(mask), data);
274 if (cur_freq == freq)
275 return 1;
276 udelay(10);
277 }
278 return 0;
279}
280
281static int acpi_cpufreq_target(struct cpufreq_policy *policy,
282 unsigned int target_freq, unsigned int relation)
283{
284 struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
285 struct acpi_processor_performance *perf;
286 struct cpufreq_freqs freqs;
287 struct drv_cmd cmd;
288 unsigned int next_state = 0; /* Index into freq_table */
289 unsigned int next_perf_state = 0; /* Index into perf table */
290 unsigned int i;
291 int result = 0;
292
293 pr_debug("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
294
295 if (unlikely(data == NULL ||
296 data->acpi_data == NULL || data->freq_table == NULL)) {
297 return -ENODEV;
298 }
299
300 perf = data->acpi_data;
301 result = cpufreq_frequency_table_target(policy,
302 data->freq_table,
303 target_freq,
304 relation, &next_state);
305 if (unlikely(result)) {
306 result = -ENODEV;
307 goto out;
308 }
309
310 next_perf_state = data->freq_table[next_state].index;
311 if (perf->state == next_perf_state) {
312 if (unlikely(data->resume)) {
313 pr_debug("Called after resume, resetting to P%d\n",
314 next_perf_state);
315 data->resume = 0;
316 } else {
317 pr_debug("Already at target state (P%d)\n",
318 next_perf_state);
319 goto out;
320 }
321 }
322
323 switch (data->cpu_feature) {
324 case SYSTEM_INTEL_MSR_CAPABLE:
325 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
326 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
327 cmd.val = (u32) perf->states[next_perf_state].control;
328 break;
329 case SYSTEM_IO_CAPABLE:
330 cmd.type = SYSTEM_IO_CAPABLE;
331 cmd.addr.io.port = perf->control_register.address;
332 cmd.addr.io.bit_width = perf->control_register.bit_width;
333 cmd.val = (u32) perf->states[next_perf_state].control;
334 break;
335 default:
336 result = -ENODEV;
337 goto out;
338 }
339
340 /* cpufreq holds the hotplug lock, so we are safe from here on */
341 if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
342 cmd.mask = policy->cpus;
343 else
344 cmd.mask = cpumask_of(policy->cpu);
345
346 freqs.old = perf->states[perf->state].core_frequency * 1000;
347 freqs.new = data->freq_table[next_state].frequency;
348 for_each_cpu(i, policy->cpus) {
349 freqs.cpu = i;
350 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
351 }
352
353 drv_write(&cmd);
354
355 if (acpi_pstate_strict) {
356 if (!check_freqs(cmd.mask, freqs.new, data)) {
357 pr_debug("acpi_cpufreq_target failed (%d)\n",
358 policy->cpu);
359 result = -EAGAIN;
360 goto out;
361 }
362 }
363
364 for_each_cpu(i, policy->cpus) {
365 freqs.cpu = i;
366 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
367 }
368 perf->state = next_perf_state;
369
370out:
371 return result;
372}
373
374static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
375{
376 struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
377
378 pr_debug("acpi_cpufreq_verify\n");
379
380 return cpufreq_frequency_table_verify(policy, data->freq_table);
381}
382
383static unsigned long
384acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
385{
386 struct acpi_processor_performance *perf = data->acpi_data;
387
388 if (cpu_khz) {
389 /* search the closest match to cpu_khz */
390 unsigned int i;
391 unsigned long freq;
392 unsigned long freqn = perf->states[0].core_frequency * 1000;
393
394 for (i = 0; i < (perf->state_count-1); i++) {
395 freq = freqn;
396 freqn = perf->states[i+1].core_frequency * 1000;
397 if ((2 * cpu_khz) > (freqn + freq)) {
398 perf->state = i;
399 return freq;
400 }
401 }
402 perf->state = perf->state_count-1;
403 return freqn;
404 } else {
405 /* assume CPU is at P0... */
406 perf->state = 0;
407 return perf->states[0].core_frequency * 1000;
408 }
409}
410
411static void free_acpi_perf_data(void)
412{
413 unsigned int i;
414
415 /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
416 for_each_possible_cpu(i)
417 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
418 ->shared_cpu_map);
419 free_percpu(acpi_perf_data);
420}
421
422/*
423 * acpi_cpufreq_early_init - initialize ACPI P-States library
424 *
425 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
426 * in order to determine correct frequency and voltage pairings. We can
427 * do _PDC and _PSD and find out the processor dependency for the
428 * actual init that will happen later...
429 */
430static int __init acpi_cpufreq_early_init(void)
431{
432 unsigned int i;
433 pr_debug("acpi_cpufreq_early_init\n");
434
435 acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
436 if (!acpi_perf_data) {
437 pr_debug("Memory allocation error for acpi_perf_data.\n");
438 return -ENOMEM;
439 }
440 for_each_possible_cpu(i) {
441 if (!zalloc_cpumask_var_node(
442 &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
443 GFP_KERNEL, cpu_to_node(i))) {
444
445 /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
446 free_acpi_perf_data();
447 return -ENOMEM;
448 }
449 }
450
451 /* Do initialization in ACPI core */
452 acpi_processor_preregister_performance(acpi_perf_data);
453 return 0;
454}
455
456#ifdef CONFIG_SMP
457/*
458 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
459 * or do it in BIOS firmware and won't inform about it to OS. If not
460 * detected, this has a side effect of making CPU run at a different speed
461 * than OS intended it to run at. Detect it and handle it cleanly.
462 */
463static int bios_with_sw_any_bug;
464
465static int sw_any_bug_found(const struct dmi_system_id *d)
466{
467 bios_with_sw_any_bug = 1;
468 return 0;
469}
470
471static const struct dmi_system_id sw_any_bug_dmi_table[] = {
472 {
473 .callback = sw_any_bug_found,
474 .ident = "Supermicro Server X6DLP",
475 .matches = {
476 DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
477 DMI_MATCH(DMI_BIOS_VERSION, "080010"),
478 DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
479 },
480 },
481 { }
482};
483
484static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
485{
486 /* Intel Xeon Processor 7100 Series Specification Update
487 * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
488 * AL30: A Machine Check Exception (MCE) Occurring during an
489 * Enhanced Intel SpeedStep Technology Ratio Change May Cause
490 * Both Processor Cores to Lock Up. */
491 if (c->x86_vendor == X86_VENDOR_INTEL) {
492 if ((c->x86 == 15) &&
493 (c->x86_model == 6) &&
494 (c->x86_mask == 8)) {
495 printk(KERN_INFO "acpi-cpufreq: Intel(R) "
496 "Xeon(R) 7100 Errata AL30, processors may "
497 "lock up on frequency changes: disabling "
498 "acpi-cpufreq.\n");
499 return -ENODEV;
500 }
501 }
502 return 0;
503}
504#endif
505
506static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
507{
508 unsigned int i;
509 unsigned int valid_states = 0;
510 unsigned int cpu = policy->cpu;
511 struct acpi_cpufreq_data *data;
512 unsigned int result = 0;
513 struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
514 struct acpi_processor_performance *perf;
515#ifdef CONFIG_SMP
516 static int blacklisted;
517#endif
518
519 pr_debug("acpi_cpufreq_cpu_init\n");
520
521#ifdef CONFIG_SMP
522 if (blacklisted)
523 return blacklisted;
524 blacklisted = acpi_cpufreq_blacklist(c);
525 if (blacklisted)
526 return blacklisted;
527#endif
528
529 data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
530 if (!data)
531 return -ENOMEM;
532
533 data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu);
534 per_cpu(acfreq_data, cpu) = data;
535
536 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
537 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
538
539 result = acpi_processor_register_performance(data->acpi_data, cpu);
540 if (result)
541 goto err_free;
542
543 perf = data->acpi_data;
544 policy->shared_type = perf->shared_type;
545
546 /*
547 * Will let policy->cpus know about dependency only when software
548 * coordination is required.
549 */
550 if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
551 policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
552 cpumask_copy(policy->cpus, perf->shared_cpu_map);
553 }
554 cpumask_copy(policy->related_cpus, perf->shared_cpu_map);
555
556#ifdef CONFIG_SMP
557 dmi_check_system(sw_any_bug_dmi_table);
558 if (bios_with_sw_any_bug && cpumask_weight(policy->cpus) == 1) {
559 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
560 cpumask_copy(policy->cpus, cpu_core_mask(cpu));
561 }
562#endif
563
564 /* capability check */
565 if (perf->state_count <= 1) {
566 pr_debug("No P-States\n");
567 result = -ENODEV;
568 goto err_unreg;
569 }
570
571 if (perf->control_register.space_id != perf->status_register.space_id) {
572 result = -ENODEV;
573 goto err_unreg;
574 }
575
576 switch (perf->control_register.space_id) {
577 case ACPI_ADR_SPACE_SYSTEM_IO:
578 pr_debug("SYSTEM IO addr space\n");
579 data->cpu_feature = SYSTEM_IO_CAPABLE;
580 break;
581 case ACPI_ADR_SPACE_FIXED_HARDWARE:
582 pr_debug("HARDWARE addr space\n");
583 if (!check_est_cpu(cpu)) {
584 result = -ENODEV;
585 goto err_unreg;
586 }
587 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
588 break;
589 default:
590 pr_debug("Unknown addr space %d\n",
591 (u32) (perf->control_register.space_id));
592 result = -ENODEV;
593 goto err_unreg;
594 }
595
596 data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
597 (perf->state_count+1), GFP_KERNEL);
598 if (!data->freq_table) {
599 result = -ENOMEM;
600 goto err_unreg;
601 }
602
603 /* detect transition latency */
604 policy->cpuinfo.transition_latency = 0;
605 for (i = 0; i < perf->state_count; i++) {
606 if ((perf->states[i].transition_latency * 1000) >
607 policy->cpuinfo.transition_latency)
608 policy->cpuinfo.transition_latency =
609 perf->states[i].transition_latency * 1000;
610 }
611
612 /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
613 if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
614 policy->cpuinfo.transition_latency > 20 * 1000) {
615 policy->cpuinfo.transition_latency = 20 * 1000;
616 printk_once(KERN_INFO
617 "P-state transition latency capped at 20 uS\n");
618 }
619
620 /* table init */
621 for (i = 0; i < perf->state_count; i++) {
622 if (i > 0 && perf->states[i].core_frequency >=
623 data->freq_table[valid_states-1].frequency / 1000)
624 continue;
625
626 data->freq_table[valid_states].index = i;
627 data->freq_table[valid_states].frequency =
628 perf->states[i].core_frequency * 1000;
629 valid_states++;
630 }
631 data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
632 perf->state = 0;
633
634 result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
635 if (result)
636 goto err_freqfree;
637
638 if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
639 printk(KERN_WARNING FW_WARN "P-state 0 is not max freq\n");
640
641 switch (perf->control_register.space_id) {
642 case ACPI_ADR_SPACE_SYSTEM_IO:
643 /* Current speed is unknown and not detectable by IO port */
644 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
645 break;
646 case ACPI_ADR_SPACE_FIXED_HARDWARE:
647 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
648 policy->cur = get_cur_freq_on_cpu(cpu);
649 break;
650 default:
651 break;
652 }
653
654 /* notify BIOS that we exist */
655 acpi_processor_notify_smm(THIS_MODULE);
656
657 /* Check for APERF/MPERF support in hardware */
658 if (boot_cpu_has(X86_FEATURE_APERFMPERF))
659 acpi_cpufreq_driver.getavg = cpufreq_get_measured_perf;
660
661 pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
662 for (i = 0; i < perf->state_count; i++)
663 pr_debug(" %cP%d: %d MHz, %d mW, %d uS\n",
664 (i == perf->state ? '*' : ' '), i,
665 (u32) perf->states[i].core_frequency,
666 (u32) perf->states[i].power,
667 (u32) perf->states[i].transition_latency);
668
669 cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
670
671 /*
672 * the first call to ->target() should result in us actually
673 * writing something to the appropriate registers.
674 */
675 data->resume = 1;
676
677 return result;
678
679err_freqfree:
680 kfree(data->freq_table);
681err_unreg:
682 acpi_processor_unregister_performance(perf, cpu);
683err_free:
684 kfree(data);
685 per_cpu(acfreq_data, cpu) = NULL;
686
687 return result;
688}
689
690static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
691{
692 struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
693
694 pr_debug("acpi_cpufreq_cpu_exit\n");
695
696 if (data) {
697 cpufreq_frequency_table_put_attr(policy->cpu);
698 per_cpu(acfreq_data, policy->cpu) = NULL;
699 acpi_processor_unregister_performance(data->acpi_data,
700 policy->cpu);
701 kfree(data->freq_table);
702 kfree(data);
703 }
704
705 return 0;
706}
707
708static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
709{
710 struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
711
712 pr_debug("acpi_cpufreq_resume\n");
713
714 data->resume = 1;
715
716 return 0;
717}
718
719static struct freq_attr *acpi_cpufreq_attr[] = {
720 &cpufreq_freq_attr_scaling_available_freqs,
721 NULL,
722};
723
724static struct cpufreq_driver acpi_cpufreq_driver = {
725 .verify = acpi_cpufreq_verify,
726 .target = acpi_cpufreq_target,
727 .bios_limit = acpi_processor_get_bios_limit,
728 .init = acpi_cpufreq_cpu_init,
729 .exit = acpi_cpufreq_cpu_exit,
730 .resume = acpi_cpufreq_resume,
731 .name = "acpi-cpufreq",
732 .owner = THIS_MODULE,
733 .attr = acpi_cpufreq_attr,
734};
735
736static int __init acpi_cpufreq_init(void)
737{
738 int ret;
739
740 if (acpi_disabled)
741 return 0;
742
743 pr_debug("acpi_cpufreq_init\n");
744
745 ret = acpi_cpufreq_early_init();
746 if (ret)
747 return ret;
748
749 ret = cpufreq_register_driver(&acpi_cpufreq_driver);
750 if (ret)
751 free_acpi_perf_data();
752
753 return ret;
754}
755
756static void __exit acpi_cpufreq_exit(void)
757{
758 pr_debug("acpi_cpufreq_exit\n");
759
760 cpufreq_unregister_driver(&acpi_cpufreq_driver);
761
762 free_acpi_perf_data();
763}
764
765module_param(acpi_pstate_strict, uint, 0644);
766MODULE_PARM_DESC(acpi_pstate_strict,
767 "value 0 or non-zero. non-zero -> strict ACPI checks are "
768 "performed during frequency changes.");
769
770late_initcall(acpi_cpufreq_init);
771module_exit(acpi_cpufreq_exit);
772
773MODULE_ALIAS("acpi");