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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");
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#include <linux/string_helpers.h>
23#include <linux/platform_device.h>
24
25#include <linux/acpi.h>
26#include <linux/io.h>
27#include <linux/delay.h>
28#include <linux/uaccess.h>
29
30#include <acpi/processor.h>
31#include <acpi/cppc_acpi.h>
32
33#include <asm/msr.h>
34#include <asm/processor.h>
35#include <asm/cpufeature.h>
36#include <asm/cpu_device_id.h>
37
38MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
39MODULE_DESCRIPTION("ACPI Processor P-States Driver");
40MODULE_LICENSE("GPL");
41
42enum {
43 UNDEFINED_CAPABLE = 0,
44 SYSTEM_INTEL_MSR_CAPABLE,
45 SYSTEM_AMD_MSR_CAPABLE,
46 SYSTEM_IO_CAPABLE,
47};
48
49#define INTEL_MSR_RANGE (0xffff)
50#define AMD_MSR_RANGE (0x7)
51#define HYGON_MSR_RANGE (0x7)
52
53#define MSR_K7_HWCR_CPB_DIS (1ULL << 25)
54
55struct acpi_cpufreq_data {
56 unsigned int resume;
57 unsigned int cpu_feature;
58 unsigned int acpi_perf_cpu;
59 cpumask_var_t freqdomain_cpus;
60 void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);
61 u32 (*cpu_freq_read)(struct acpi_pct_register *reg);
62};
63
64/* acpi_perf_data is a pointer to percpu data. */
65static struct acpi_processor_performance __percpu *acpi_perf_data;
66
67static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
68{
69 return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
70}
71
72static struct cpufreq_driver acpi_cpufreq_driver;
73
74static unsigned int acpi_pstate_strict;
75
76static bool boost_state(unsigned int cpu)
77{
78 u32 lo, hi;
79 u64 msr;
80
81 switch (boot_cpu_data.x86_vendor) {
82 case X86_VENDOR_INTEL:
83 case X86_VENDOR_CENTAUR:
84 case X86_VENDOR_ZHAOXIN:
85 rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
86 msr = lo | ((u64)hi << 32);
87 return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
88 case X86_VENDOR_HYGON:
89 case X86_VENDOR_AMD:
90 rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
91 msr = lo | ((u64)hi << 32);
92 return !(msr & MSR_K7_HWCR_CPB_DIS);
93 }
94 return false;
95}
96
97static int boost_set_msr(bool enable)
98{
99 u32 msr_addr;
100 u64 msr_mask, val;
101
102 switch (boot_cpu_data.x86_vendor) {
103 case X86_VENDOR_INTEL:
104 case X86_VENDOR_CENTAUR:
105 case X86_VENDOR_ZHAOXIN:
106 msr_addr = MSR_IA32_MISC_ENABLE;
107 msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
108 break;
109 case X86_VENDOR_HYGON:
110 case X86_VENDOR_AMD:
111 msr_addr = MSR_K7_HWCR;
112 msr_mask = MSR_K7_HWCR_CPB_DIS;
113 break;
114 default:
115 return -EINVAL;
116 }
117
118 rdmsrl(msr_addr, val);
119
120 if (enable)
121 val &= ~msr_mask;
122 else
123 val |= msr_mask;
124
125 wrmsrl(msr_addr, val);
126 return 0;
127}
128
129static void boost_set_msr_each(void *p_en)
130{
131 bool enable = (bool) p_en;
132
133 boost_set_msr(enable);
134}
135
136static int set_boost(struct cpufreq_policy *policy, int val)
137{
138 on_each_cpu_mask(policy->cpus, boost_set_msr_each,
139 (void *)(long)val, 1);
140 pr_debug("CPU %*pbl: Core Boosting %s.\n",
141 cpumask_pr_args(policy->cpus), str_enabled_disabled(val));
142
143 return 0;
144}
145
146static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
147{
148 struct acpi_cpufreq_data *data = policy->driver_data;
149
150 if (unlikely(!data))
151 return -ENODEV;
152
153 return cpufreq_show_cpus(data->freqdomain_cpus, buf);
154}
155
156cpufreq_freq_attr_ro(freqdomain_cpus);
157
158#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
159static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
160 size_t count)
161{
162 int ret;
163 unsigned int val = 0;
164
165 if (!acpi_cpufreq_driver.set_boost)
166 return -EINVAL;
167
168 ret = kstrtouint(buf, 10, &val);
169 if (ret || val > 1)
170 return -EINVAL;
171
172 cpus_read_lock();
173 set_boost(policy, val);
174 cpus_read_unlock();
175
176 return count;
177}
178
179static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
180{
181 return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
182}
183
184cpufreq_freq_attr_rw(cpb);
185#endif
186
187static int check_est_cpu(unsigned int cpuid)
188{
189 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
190
191 return cpu_has(cpu, X86_FEATURE_EST);
192}
193
194static int check_amd_hwpstate_cpu(unsigned int cpuid)
195{
196 struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
197
198 return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
199}
200
201static unsigned extract_io(struct cpufreq_policy *policy, u32 value)
202{
203 struct acpi_cpufreq_data *data = policy->driver_data;
204 struct acpi_processor_performance *perf;
205 int i;
206
207 perf = to_perf_data(data);
208
209 for (i = 0; i < perf->state_count; i++) {
210 if (value == perf->states[i].status)
211 return policy->freq_table[i].frequency;
212 }
213 return 0;
214}
215
216static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
217{
218 struct acpi_cpufreq_data *data = policy->driver_data;
219 struct cpufreq_frequency_table *pos;
220 struct acpi_processor_performance *perf;
221
222 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
223 msr &= AMD_MSR_RANGE;
224 else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
225 msr &= HYGON_MSR_RANGE;
226 else
227 msr &= INTEL_MSR_RANGE;
228
229 perf = to_perf_data(data);
230
231 cpufreq_for_each_entry(pos, policy->freq_table)
232 if (msr == perf->states[pos->driver_data].status)
233 return pos->frequency;
234 return policy->freq_table[0].frequency;
235}
236
237static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
238{
239 struct acpi_cpufreq_data *data = policy->driver_data;
240
241 switch (data->cpu_feature) {
242 case SYSTEM_INTEL_MSR_CAPABLE:
243 case SYSTEM_AMD_MSR_CAPABLE:
244 return extract_msr(policy, val);
245 case SYSTEM_IO_CAPABLE:
246 return extract_io(policy, val);
247 default:
248 return 0;
249 }
250}
251
252static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
253{
254 u32 val, dummy __always_unused;
255
256 rdmsr(MSR_IA32_PERF_CTL, val, dummy);
257 return val;
258}
259
260static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
261{
262 u32 lo, hi;
263
264 rdmsr(MSR_IA32_PERF_CTL, lo, hi);
265 lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
266 wrmsr(MSR_IA32_PERF_CTL, lo, hi);
267}
268
269static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
270{
271 u32 val, dummy __always_unused;
272
273 rdmsr(MSR_AMD_PERF_CTL, val, dummy);
274 return val;
275}
276
277static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
278{
279 wrmsr(MSR_AMD_PERF_CTL, val, 0);
280}
281
282static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
283{
284 u32 val;
285
286 acpi_os_read_port(reg->address, &val, reg->bit_width);
287 return val;
288}
289
290static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
291{
292 acpi_os_write_port(reg->address, val, reg->bit_width);
293}
294
295struct drv_cmd {
296 struct acpi_pct_register *reg;
297 u32 val;
298 union {
299 void (*write)(struct acpi_pct_register *reg, u32 val);
300 u32 (*read)(struct acpi_pct_register *reg);
301 } func;
302};
303
304/* Called via smp_call_function_single(), on the target CPU */
305static void do_drv_read(void *_cmd)
306{
307 struct drv_cmd *cmd = _cmd;
308
309 cmd->val = cmd->func.read(cmd->reg);
310}
311
312static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
313{
314 struct acpi_processor_performance *perf = to_perf_data(data);
315 struct drv_cmd cmd = {
316 .reg = &perf->control_register,
317 .func.read = data->cpu_freq_read,
318 };
319 int err;
320
321 err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
322 WARN_ON_ONCE(err); /* smp_call_function_any() was buggy? */
323 return cmd.val;
324}
325
326/* Called via smp_call_function_many(), on the target CPUs */
327static void do_drv_write(void *_cmd)
328{
329 struct drv_cmd *cmd = _cmd;
330
331 cmd->func.write(cmd->reg, cmd->val);
332}
333
334static void drv_write(struct acpi_cpufreq_data *data,
335 const struct cpumask *mask, u32 val)
336{
337 struct acpi_processor_performance *perf = to_perf_data(data);
338 struct drv_cmd cmd = {
339 .reg = &perf->control_register,
340 .val = val,
341 .func.write = data->cpu_freq_write,
342 };
343 int this_cpu;
344
345 this_cpu = get_cpu();
346 if (cpumask_test_cpu(this_cpu, mask))
347 do_drv_write(&cmd);
348
349 smp_call_function_many(mask, do_drv_write, &cmd, 1);
350 put_cpu();
351}
352
353static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
354{
355 u32 val;
356
357 if (unlikely(cpumask_empty(mask)))
358 return 0;
359
360 val = drv_read(data, mask);
361
362 pr_debug("%s = %u\n", __func__, val);
363
364 return val;
365}
366
367static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
368{
369 struct acpi_cpufreq_data *data;
370 struct cpufreq_policy *policy;
371 unsigned int freq;
372 unsigned int cached_freq;
373
374 pr_debug("%s (%d)\n", __func__, cpu);
375
376 policy = cpufreq_cpu_get_raw(cpu);
377 if (unlikely(!policy))
378 return 0;
379
380 data = policy->driver_data;
381 if (unlikely(!data || !policy->freq_table))
382 return 0;
383
384 cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;
385 freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));
386 if (freq != cached_freq) {
387 /*
388 * The dreaded BIOS frequency change behind our back.
389 * Force set the frequency on next target call.
390 */
391 data->resume = 1;
392 }
393
394 pr_debug("cur freq = %u\n", freq);
395
396 return freq;
397}
398
399static unsigned int check_freqs(struct cpufreq_policy *policy,
400 const struct cpumask *mask, unsigned int freq)
401{
402 struct acpi_cpufreq_data *data = policy->driver_data;
403 unsigned int cur_freq;
404 unsigned int i;
405
406 for (i = 0; i < 100; i++) {
407 cur_freq = extract_freq(policy, get_cur_val(mask, data));
408 if (cur_freq == freq)
409 return 1;
410 udelay(10);
411 }
412 return 0;
413}
414
415static int acpi_cpufreq_target(struct cpufreq_policy *policy,
416 unsigned int index)
417{
418 struct acpi_cpufreq_data *data = policy->driver_data;
419 struct acpi_processor_performance *perf;
420 const struct cpumask *mask;
421 unsigned int next_perf_state = 0; /* Index into perf table */
422 int result = 0;
423
424 if (unlikely(!data)) {
425 return -ENODEV;
426 }
427
428 perf = to_perf_data(data);
429 next_perf_state = policy->freq_table[index].driver_data;
430 if (perf->state == next_perf_state) {
431 if (unlikely(data->resume)) {
432 pr_debug("Called after resume, resetting to P%d\n",
433 next_perf_state);
434 data->resume = 0;
435 } else {
436 pr_debug("Already at target state (P%d)\n",
437 next_perf_state);
438 return 0;
439 }
440 }
441
442 /*
443 * The core won't allow CPUs to go away until the governor has been
444 * stopped, so we can rely on the stability of policy->cpus.
445 */
446 mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
447 cpumask_of(policy->cpu) : policy->cpus;
448
449 drv_write(data, mask, perf->states[next_perf_state].control);
450
451 if (acpi_pstate_strict) {
452 if (!check_freqs(policy, mask,
453 policy->freq_table[index].frequency)) {
454 pr_debug("%s (%d)\n", __func__, policy->cpu);
455 result = -EAGAIN;
456 }
457 }
458
459 if (!result)
460 perf->state = next_perf_state;
461
462 return result;
463}
464
465static unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
466 unsigned int target_freq)
467{
468 struct acpi_cpufreq_data *data = policy->driver_data;
469 struct acpi_processor_performance *perf;
470 struct cpufreq_frequency_table *entry;
471 unsigned int next_perf_state, next_freq, index;
472
473 /*
474 * Find the closest frequency above target_freq.
475 */
476 if (policy->cached_target_freq == target_freq)
477 index = policy->cached_resolved_idx;
478 else
479 index = cpufreq_table_find_index_dl(policy, target_freq,
480 false);
481
482 entry = &policy->freq_table[index];
483 next_freq = entry->frequency;
484 next_perf_state = entry->driver_data;
485
486 perf = to_perf_data(data);
487 if (perf->state == next_perf_state) {
488 if (unlikely(data->resume))
489 data->resume = 0;
490 else
491 return next_freq;
492 }
493
494 data->cpu_freq_write(&perf->control_register,
495 perf->states[next_perf_state].control);
496 perf->state = next_perf_state;
497 return next_freq;
498}
499
500static unsigned long
501acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
502{
503 struct acpi_processor_performance *perf;
504
505 perf = to_perf_data(data);
506 if (cpu_khz) {
507 /* search the closest match to cpu_khz */
508 unsigned int i;
509 unsigned long freq;
510 unsigned long freqn = perf->states[0].core_frequency * 1000;
511
512 for (i = 0; i < (perf->state_count-1); i++) {
513 freq = freqn;
514 freqn = perf->states[i+1].core_frequency * 1000;
515 if ((2 * cpu_khz) > (freqn + freq)) {
516 perf->state = i;
517 return freq;
518 }
519 }
520 perf->state = perf->state_count-1;
521 return freqn;
522 } else {
523 /* assume CPU is at P0... */
524 perf->state = 0;
525 return perf->states[0].core_frequency * 1000;
526 }
527}
528
529static void free_acpi_perf_data(void)
530{
531 unsigned int i;
532
533 /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
534 for_each_possible_cpu(i)
535 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
536 ->shared_cpu_map);
537 free_percpu(acpi_perf_data);
538}
539
540static int cpufreq_boost_down_prep(unsigned int cpu)
541{
542 /*
543 * Clear the boost-disable bit on the CPU_DOWN path so that
544 * this cpu cannot block the remaining ones from boosting.
545 */
546 return boost_set_msr(1);
547}
548
549/*
550 * acpi_cpufreq_early_init - initialize ACPI P-States library
551 *
552 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
553 * in order to determine correct frequency and voltage pairings. We can
554 * do _PDC and _PSD and find out the processor dependency for the
555 * actual init that will happen later...
556 */
557static int __init acpi_cpufreq_early_init(void)
558{
559 unsigned int i;
560 pr_debug("%s\n", __func__);
561
562 acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
563 if (!acpi_perf_data) {
564 pr_debug("Memory allocation error for acpi_perf_data.\n");
565 return -ENOMEM;
566 }
567 for_each_possible_cpu(i) {
568 if (!zalloc_cpumask_var_node(
569 &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
570 GFP_KERNEL, cpu_to_node(i))) {
571
572 /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
573 free_acpi_perf_data();
574 return -ENOMEM;
575 }
576 }
577
578 /* Do initialization in ACPI core */
579 acpi_processor_preregister_performance(acpi_perf_data);
580 return 0;
581}
582
583#ifdef CONFIG_SMP
584/*
585 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
586 * or do it in BIOS firmware and won't inform about it to OS. If not
587 * detected, this has a side effect of making CPU run at a different speed
588 * than OS intended it to run at. Detect it and handle it cleanly.
589 */
590static int bios_with_sw_any_bug;
591
592static int sw_any_bug_found(const struct dmi_system_id *d)
593{
594 bios_with_sw_any_bug = 1;
595 return 0;
596}
597
598static const struct dmi_system_id sw_any_bug_dmi_table[] = {
599 {
600 .callback = sw_any_bug_found,
601 .ident = "Supermicro Server X6DLP",
602 .matches = {
603 DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
604 DMI_MATCH(DMI_BIOS_VERSION, "080010"),
605 DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
606 },
607 },
608 { }
609};
610
611static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
612{
613 /* Intel Xeon Processor 7100 Series Specification Update
614 * https://www.intel.com/Assets/PDF/specupdate/314554.pdf
615 * AL30: A Machine Check Exception (MCE) Occurring during an
616 * Enhanced Intel SpeedStep Technology Ratio Change May Cause
617 * Both Processor Cores to Lock Up. */
618 if (c->x86_vendor == X86_VENDOR_INTEL) {
619 if ((c->x86 == 15) &&
620 (c->x86_model == 6) &&
621 (c->x86_stepping == 8)) {
622 pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");
623 return -ENODEV;
624 }
625 }
626 return 0;
627}
628#endif
629
630#ifdef CONFIG_ACPI_CPPC_LIB
631static u64 get_max_boost_ratio(unsigned int cpu)
632{
633 struct cppc_perf_caps perf_caps;
634 u64 highest_perf, nominal_perf;
635 int ret;
636
637 if (acpi_pstate_strict)
638 return 0;
639
640 ret = cppc_get_perf_caps(cpu, &perf_caps);
641 if (ret) {
642 pr_debug("CPU%d: Unable to get performance capabilities (%d)\n",
643 cpu, ret);
644 return 0;
645 }
646
647 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
648 highest_perf = amd_get_highest_perf();
649 else
650 highest_perf = perf_caps.highest_perf;
651
652 nominal_perf = perf_caps.nominal_perf;
653
654 if (!highest_perf || !nominal_perf) {
655 pr_debug("CPU%d: highest or nominal performance missing\n", cpu);
656 return 0;
657 }
658
659 if (highest_perf < nominal_perf) {
660 pr_debug("CPU%d: nominal performance above highest\n", cpu);
661 return 0;
662 }
663
664 return div_u64(highest_perf << SCHED_CAPACITY_SHIFT, nominal_perf);
665}
666#else
667static inline u64 get_max_boost_ratio(unsigned int cpu) { return 0; }
668#endif
669
670static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
671{
672 struct cpufreq_frequency_table *freq_table;
673 struct acpi_processor_performance *perf;
674 struct acpi_cpufreq_data *data;
675 unsigned int cpu = policy->cpu;
676 struct cpuinfo_x86 *c = &cpu_data(cpu);
677 unsigned int valid_states = 0;
678 unsigned int result = 0;
679 u64 max_boost_ratio;
680 unsigned int i;
681#ifdef CONFIG_SMP
682 static int blacklisted;
683#endif
684
685 pr_debug("%s\n", __func__);
686
687#ifdef CONFIG_SMP
688 if (blacklisted)
689 return blacklisted;
690 blacklisted = acpi_cpufreq_blacklist(c);
691 if (blacklisted)
692 return blacklisted;
693#endif
694
695 data = kzalloc(sizeof(*data), GFP_KERNEL);
696 if (!data)
697 return -ENOMEM;
698
699 if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
700 result = -ENOMEM;
701 goto err_free;
702 }
703
704 perf = per_cpu_ptr(acpi_perf_data, cpu);
705 data->acpi_perf_cpu = cpu;
706 policy->driver_data = data;
707
708 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
709 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
710
711 result = acpi_processor_register_performance(perf, cpu);
712 if (result)
713 goto err_free_mask;
714
715 policy->shared_type = perf->shared_type;
716
717 /*
718 * Will let policy->cpus know about dependency only when software
719 * coordination is required.
720 */
721 if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
722 policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
723 cpumask_copy(policy->cpus, perf->shared_cpu_map);
724 }
725 cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
726
727#ifdef CONFIG_SMP
728 dmi_check_system(sw_any_bug_dmi_table);
729 if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
730 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
731 cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
732 }
733
734 if (check_amd_hwpstate_cpu(cpu) && boot_cpu_data.x86 < 0x19 &&
735 !acpi_pstate_strict) {
736 cpumask_clear(policy->cpus);
737 cpumask_set_cpu(cpu, policy->cpus);
738 cpumask_copy(data->freqdomain_cpus,
739 topology_sibling_cpumask(cpu));
740 policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
741 pr_info_once("overriding BIOS provided _PSD data\n");
742 }
743#endif
744
745 /* capability check */
746 if (perf->state_count <= 1) {
747 pr_debug("No P-States\n");
748 result = -ENODEV;
749 goto err_unreg;
750 }
751
752 if (perf->control_register.space_id != perf->status_register.space_id) {
753 result = -ENODEV;
754 goto err_unreg;
755 }
756
757 switch (perf->control_register.space_id) {
758 case ACPI_ADR_SPACE_SYSTEM_IO:
759 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
760 boot_cpu_data.x86 == 0xf) {
761 pr_debug("AMD K8 systems must use native drivers.\n");
762 result = -ENODEV;
763 goto err_unreg;
764 }
765 pr_debug("SYSTEM IO addr space\n");
766 data->cpu_feature = SYSTEM_IO_CAPABLE;
767 data->cpu_freq_read = cpu_freq_read_io;
768 data->cpu_freq_write = cpu_freq_write_io;
769 break;
770 case ACPI_ADR_SPACE_FIXED_HARDWARE:
771 pr_debug("HARDWARE addr space\n");
772 if (check_est_cpu(cpu)) {
773 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
774 data->cpu_freq_read = cpu_freq_read_intel;
775 data->cpu_freq_write = cpu_freq_write_intel;
776 break;
777 }
778 if (check_amd_hwpstate_cpu(cpu)) {
779 data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
780 data->cpu_freq_read = cpu_freq_read_amd;
781 data->cpu_freq_write = cpu_freq_write_amd;
782 break;
783 }
784 result = -ENODEV;
785 goto err_unreg;
786 default:
787 pr_debug("Unknown addr space %d\n",
788 (u32) (perf->control_register.space_id));
789 result = -ENODEV;
790 goto err_unreg;
791 }
792
793 freq_table = kcalloc(perf->state_count + 1, sizeof(*freq_table),
794 GFP_KERNEL);
795 if (!freq_table) {
796 result = -ENOMEM;
797 goto err_unreg;
798 }
799
800 /* detect transition latency */
801 policy->cpuinfo.transition_latency = 0;
802 for (i = 0; i < perf->state_count; i++) {
803 if ((perf->states[i].transition_latency * 1000) >
804 policy->cpuinfo.transition_latency)
805 policy->cpuinfo.transition_latency =
806 perf->states[i].transition_latency * 1000;
807 }
808
809 /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
810 if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
811 policy->cpuinfo.transition_latency > 20 * 1000) {
812 policy->cpuinfo.transition_latency = 20 * 1000;
813 pr_info_once("P-state transition latency capped at 20 uS\n");
814 }
815
816 /* table init */
817 for (i = 0; i < perf->state_count; i++) {
818 if (i > 0 && perf->states[i].core_frequency >=
819 freq_table[valid_states-1].frequency / 1000)
820 continue;
821
822 freq_table[valid_states].driver_data = i;
823 freq_table[valid_states].frequency =
824 perf->states[i].core_frequency * 1000;
825 valid_states++;
826 }
827 freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
828
829 max_boost_ratio = get_max_boost_ratio(cpu);
830 if (max_boost_ratio) {
831 unsigned int freq = freq_table[0].frequency;
832
833 /*
834 * Because the loop above sorts the freq_table entries in the
835 * descending order, freq is the maximum frequency in the table.
836 * Assume that it corresponds to the CPPC nominal frequency and
837 * use it to set cpuinfo.max_freq.
838 */
839 policy->cpuinfo.max_freq = freq * max_boost_ratio >> SCHED_CAPACITY_SHIFT;
840 } else {
841 /*
842 * If the maximum "boost" frequency is unknown, ask the arch
843 * scale-invariance code to use the "nominal" performance for
844 * CPU utilization scaling so as to prevent the schedutil
845 * governor from selecting inadequate CPU frequencies.
846 */
847 arch_set_max_freq_ratio(true);
848 }
849
850 policy->freq_table = freq_table;
851 perf->state = 0;
852
853 switch (perf->control_register.space_id) {
854 case ACPI_ADR_SPACE_SYSTEM_IO:
855 /*
856 * The core will not set policy->cur, because
857 * cpufreq_driver->get is NULL, so we need to set it here.
858 * However, we have to guess it, because the current speed is
859 * unknown and not detectable via IO ports.
860 */
861 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
862 break;
863 case ACPI_ADR_SPACE_FIXED_HARDWARE:
864 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
865 break;
866 default:
867 break;
868 }
869
870 /* notify BIOS that we exist */
871 acpi_processor_notify_smm(THIS_MODULE);
872
873 pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
874 for (i = 0; i < perf->state_count; i++)
875 pr_debug(" %cP%d: %d MHz, %d mW, %d uS\n",
876 (i == perf->state ? '*' : ' '), i,
877 (u32) perf->states[i].core_frequency,
878 (u32) perf->states[i].power,
879 (u32) perf->states[i].transition_latency);
880
881 /*
882 * the first call to ->target() should result in us actually
883 * writing something to the appropriate registers.
884 */
885 data->resume = 1;
886
887 policy->fast_switch_possible = !acpi_pstate_strict &&
888 !(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);
889
890 if (perf->states[0].core_frequency * 1000 != freq_table[0].frequency)
891 pr_warn(FW_WARN "P-state 0 is not max freq\n");
892
893 if (acpi_cpufreq_driver.set_boost)
894 set_boost(policy, acpi_cpufreq_driver.boost_enabled);
895
896 return result;
897
898err_unreg:
899 acpi_processor_unregister_performance(cpu);
900err_free_mask:
901 free_cpumask_var(data->freqdomain_cpus);
902err_free:
903 kfree(data);
904 policy->driver_data = NULL;
905
906 return result;
907}
908
909static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
910{
911 struct acpi_cpufreq_data *data = policy->driver_data;
912
913 pr_debug("%s\n", __func__);
914
915 cpufreq_boost_down_prep(policy->cpu);
916 policy->fast_switch_possible = false;
917 policy->driver_data = NULL;
918 acpi_processor_unregister_performance(data->acpi_perf_cpu);
919 free_cpumask_var(data->freqdomain_cpus);
920 kfree(policy->freq_table);
921 kfree(data);
922
923 return 0;
924}
925
926static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
927{
928 struct acpi_cpufreq_data *data = policy->driver_data;
929
930 pr_debug("%s\n", __func__);
931
932 data->resume = 1;
933
934 return 0;
935}
936
937static struct freq_attr *acpi_cpufreq_attr[] = {
938 &cpufreq_freq_attr_scaling_available_freqs,
939 &freqdomain_cpus,
940#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
941 &cpb,
942#endif
943 NULL,
944};
945
946static struct cpufreq_driver acpi_cpufreq_driver = {
947 .verify = cpufreq_generic_frequency_table_verify,
948 .target_index = acpi_cpufreq_target,
949 .fast_switch = acpi_cpufreq_fast_switch,
950 .bios_limit = acpi_processor_get_bios_limit,
951 .init = acpi_cpufreq_cpu_init,
952 .exit = acpi_cpufreq_cpu_exit,
953 .resume = acpi_cpufreq_resume,
954 .name = "acpi-cpufreq",
955 .attr = acpi_cpufreq_attr,
956};
957
958static void __init acpi_cpufreq_boost_init(void)
959{
960 if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA))) {
961 pr_debug("Boost capabilities not present in the processor\n");
962 return;
963 }
964
965 acpi_cpufreq_driver.set_boost = set_boost;
966 acpi_cpufreq_driver.boost_enabled = boost_state(0);
967}
968
969static int __init acpi_cpufreq_probe(struct platform_device *pdev)
970{
971 int ret;
972
973 if (acpi_disabled)
974 return -ENODEV;
975
976 /* don't keep reloading if cpufreq_driver exists */
977 if (cpufreq_get_current_driver())
978 return -ENODEV;
979
980 pr_debug("%s\n", __func__);
981
982 ret = acpi_cpufreq_early_init();
983 if (ret)
984 return ret;
985
986#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
987 /* this is a sysfs file with a strange name and an even stranger
988 * semantic - per CPU instantiation, but system global effect.
989 * Lets enable it only on AMD CPUs for compatibility reasons and
990 * only if configured. This is considered legacy code, which
991 * will probably be removed at some point in the future.
992 */
993 if (!check_amd_hwpstate_cpu(0)) {
994 struct freq_attr **attr;
995
996 pr_debug("CPB unsupported, do not expose it\n");
997
998 for (attr = acpi_cpufreq_attr; *attr; attr++)
999 if (*attr == &cpb) {
1000 *attr = NULL;
1001 break;
1002 }
1003 }
1004#endif
1005 acpi_cpufreq_boost_init();
1006
1007 ret = cpufreq_register_driver(&acpi_cpufreq_driver);
1008 if (ret) {
1009 free_acpi_perf_data();
1010 }
1011 return ret;
1012}
1013
1014static void acpi_cpufreq_remove(struct platform_device *pdev)
1015{
1016 pr_debug("%s\n", __func__);
1017
1018 cpufreq_unregister_driver(&acpi_cpufreq_driver);
1019
1020 free_acpi_perf_data();
1021}
1022
1023static struct platform_driver acpi_cpufreq_platdrv = {
1024 .driver = {
1025 .name = "acpi-cpufreq",
1026 },
1027 .remove_new = acpi_cpufreq_remove,
1028};
1029
1030static int __init acpi_cpufreq_init(void)
1031{
1032 return platform_driver_probe(&acpi_cpufreq_platdrv, acpi_cpufreq_probe);
1033}
1034
1035static void __exit acpi_cpufreq_exit(void)
1036{
1037 platform_driver_unregister(&acpi_cpufreq_platdrv);
1038}
1039
1040module_param(acpi_pstate_strict, uint, 0644);
1041MODULE_PARM_DESC(acpi_pstate_strict,
1042 "value 0 or non-zero. non-zero -> strict ACPI checks are "
1043 "performed during frequency changes.");
1044
1045late_initcall(acpi_cpufreq_init);
1046module_exit(acpi_cpufreq_exit);
1047
1048MODULE_ALIAS("platform:acpi-cpufreq");