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Dirk Brandewie93f08222013-02-06 09:02:13 -08001/*
Srinivas Pandruvadad1b68482013-04-09 22:38:18 +00002 * intel_pstate.c: Native P state management for Intel processors
Dirk Brandewie93f08222013-02-06 09:02:13 -08003 *
4 * (C) Copyright 2012 Intel Corporation
5 * Author: Dirk Brandewie <dirk.j.brandewie@intel.com>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; version 2
10 * of the License.
11 */
12
13#include <linux/kernel.h>
14#include <linux/kernel_stat.h>
15#include <linux/module.h>
16#include <linux/ktime.h>
17#include <linux/hrtimer.h>
18#include <linux/tick.h>
19#include <linux/slab.h>
20#include <linux/sched.h>
21#include <linux/list.h>
22#include <linux/cpu.h>
23#include <linux/cpufreq.h>
24#include <linux/sysfs.h>
25#include <linux/types.h>
26#include <linux/fs.h>
27#include <linux/debugfs.h>
28#include <trace/events/power.h>
29
30#include <asm/div64.h>
31#include <asm/msr.h>
32#include <asm/cpu_device_id.h>
33
34#define SAMPLE_COUNT 3
35
36#define FRAC_BITS 8
37#define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
38#define fp_toint(X) ((X) >> FRAC_BITS)
39
40static inline int32_t mul_fp(int32_t x, int32_t y)
41{
42 return ((int64_t)x * (int64_t)y) >> FRAC_BITS;
43}
44
45static inline int32_t div_fp(int32_t x, int32_t y)
46{
47 return div_s64((int64_t)x << FRAC_BITS, (int64_t)y);
48}
49
50struct sample {
51 ktime_t start_time;
52 ktime_t end_time;
53 int core_pct_busy;
54 int pstate_pct_busy;
55 u64 duration_us;
56 u64 idletime_us;
57 u64 aperf;
58 u64 mperf;
59 int freq;
60};
61
62struct pstate_data {
63 int current_pstate;
64 int min_pstate;
65 int max_pstate;
66 int turbo_pstate;
67};
68
69struct _pid {
70 int setpoint;
71 int32_t integral;
72 int32_t p_gain;
73 int32_t i_gain;
74 int32_t d_gain;
75 int deadband;
76 int last_err;
77};
78
79struct cpudata {
80 int cpu;
81
82 char name[64];
83
84 struct timer_list timer;
85
86 struct pstate_adjust_policy *pstate_policy;
87 struct pstate_data pstate;
88 struct _pid pid;
89 struct _pid idle_pid;
90
91 int min_pstate_count;
92 int idle_mode;
93
94 ktime_t prev_sample;
95 u64 prev_idle_time_us;
96 u64 prev_aperf;
97 u64 prev_mperf;
98 int sample_ptr;
99 struct sample samples[SAMPLE_COUNT];
100};
101
102static struct cpudata **all_cpu_data;
103struct pstate_adjust_policy {
104 int sample_rate_ms;
105 int deadband;
106 int setpoint;
107 int p_gain_pct;
108 int d_gain_pct;
109 int i_gain_pct;
110};
111
112static struct pstate_adjust_policy default_policy = {
113 .sample_rate_ms = 10,
114 .deadband = 0,
115 .setpoint = 109,
116 .p_gain_pct = 17,
117 .d_gain_pct = 0,
118 .i_gain_pct = 4,
119};
120
121struct perf_limits {
122 int no_turbo;
123 int max_perf_pct;
124 int min_perf_pct;
125 int32_t max_perf;
126 int32_t min_perf;
127};
128
129static struct perf_limits limits = {
130 .no_turbo = 0,
131 .max_perf_pct = 100,
132 .max_perf = int_tofp(1),
133 .min_perf_pct = 0,
134 .min_perf = 0,
135};
136
137static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
138 int deadband, int integral) {
139 pid->setpoint = setpoint;
140 pid->deadband = deadband;
141 pid->integral = int_tofp(integral);
142 pid->last_err = setpoint - busy;
143}
144
145static inline void pid_p_gain_set(struct _pid *pid, int percent)
146{
147 pid->p_gain = div_fp(int_tofp(percent), int_tofp(100));
148}
149
150static inline void pid_i_gain_set(struct _pid *pid, int percent)
151{
152 pid->i_gain = div_fp(int_tofp(percent), int_tofp(100));
153}
154
155static inline void pid_d_gain_set(struct _pid *pid, int percent)
156{
157
158 pid->d_gain = div_fp(int_tofp(percent), int_tofp(100));
159}
160
161static signed int pid_calc(struct _pid *pid, int busy)
162{
163 signed int err, result;
164 int32_t pterm, dterm, fp_error;
165 int32_t integral_limit;
166
167 err = pid->setpoint - busy;
168 fp_error = int_tofp(err);
169
170 if (abs(err) <= pid->deadband)
171 return 0;
172
173 pterm = mul_fp(pid->p_gain, fp_error);
174
175 pid->integral += fp_error;
176
177 /* limit the integral term */
178 integral_limit = int_tofp(30);
179 if (pid->integral > integral_limit)
180 pid->integral = integral_limit;
181 if (pid->integral < -integral_limit)
182 pid->integral = -integral_limit;
183
184 dterm = mul_fp(pid->d_gain, (err - pid->last_err));
185 pid->last_err = err;
186
187 result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm;
188
189 return (signed int)fp_toint(result);
190}
191
192static inline void intel_pstate_busy_pid_reset(struct cpudata *cpu)
193{
194 pid_p_gain_set(&cpu->pid, cpu->pstate_policy->p_gain_pct);
195 pid_d_gain_set(&cpu->pid, cpu->pstate_policy->d_gain_pct);
196 pid_i_gain_set(&cpu->pid, cpu->pstate_policy->i_gain_pct);
197
198 pid_reset(&cpu->pid,
199 cpu->pstate_policy->setpoint,
200 100,
201 cpu->pstate_policy->deadband,
202 0);
203}
204
205static inline void intel_pstate_idle_pid_reset(struct cpudata *cpu)
206{
207 pid_p_gain_set(&cpu->idle_pid, cpu->pstate_policy->p_gain_pct);
208 pid_d_gain_set(&cpu->idle_pid, cpu->pstate_policy->d_gain_pct);
209 pid_i_gain_set(&cpu->idle_pid, cpu->pstate_policy->i_gain_pct);
210
211 pid_reset(&cpu->idle_pid,
212 75,
213 50,
214 cpu->pstate_policy->deadband,
215 0);
216}
217
218static inline void intel_pstate_reset_all_pid(void)
219{
220 unsigned int cpu;
221 for_each_online_cpu(cpu) {
222 if (all_cpu_data[cpu])
223 intel_pstate_busy_pid_reset(all_cpu_data[cpu]);
224 }
225}
226
227/************************** debugfs begin ************************/
228static int pid_param_set(void *data, u64 val)
229{
230 *(u32 *)data = val;
231 intel_pstate_reset_all_pid();
232 return 0;
233}
234static int pid_param_get(void *data, u64 *val)
235{
236 *val = *(u32 *)data;
237 return 0;
238}
239DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get,
240 pid_param_set, "%llu\n");
241
242struct pid_param {
243 char *name;
244 void *value;
245};
246
247static struct pid_param pid_files[] = {
248 {"sample_rate_ms", &default_policy.sample_rate_ms},
249 {"d_gain_pct", &default_policy.d_gain_pct},
250 {"i_gain_pct", &default_policy.i_gain_pct},
251 {"deadband", &default_policy.deadband},
252 {"setpoint", &default_policy.setpoint},
253 {"p_gain_pct", &default_policy.p_gain_pct},
254 {NULL, NULL}
255};
256
257static struct dentry *debugfs_parent;
258static void intel_pstate_debug_expose_params(void)
259{
260 int i = 0;
261
262 debugfs_parent = debugfs_create_dir("pstate_snb", NULL);
263 if (IS_ERR_OR_NULL(debugfs_parent))
264 return;
265 while (pid_files[i].name) {
266 debugfs_create_file(pid_files[i].name, 0660,
267 debugfs_parent, pid_files[i].value,
268 &fops_pid_param);
269 i++;
270 }
271}
272
273/************************** debugfs end ************************/
274
275/************************** sysfs begin ************************/
276#define show_one(file_name, object) \
277 static ssize_t show_##file_name \
278 (struct kobject *kobj, struct attribute *attr, char *buf) \
279 { \
280 return sprintf(buf, "%u\n", limits.object); \
281 }
282
283static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
284 const char *buf, size_t count)
285{
286 unsigned int input;
287 int ret;
288 ret = sscanf(buf, "%u", &input);
289 if (ret != 1)
290 return -EINVAL;
291 limits.no_turbo = clamp_t(int, input, 0 , 1);
292
293 return count;
294}
295
296static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
297 const char *buf, size_t count)
298{
299 unsigned int input;
300 int ret;
301 ret = sscanf(buf, "%u", &input);
302 if (ret != 1)
303 return -EINVAL;
304
305 limits.max_perf_pct = clamp_t(int, input, 0 , 100);
306 limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
307 return count;
308}
309
310static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
311 const char *buf, size_t count)
312{
313 unsigned int input;
314 int ret;
315 ret = sscanf(buf, "%u", &input);
316 if (ret != 1)
317 return -EINVAL;
318 limits.min_perf_pct = clamp_t(int, input, 0 , 100);
319 limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
320
321 return count;
322}
323
324show_one(no_turbo, no_turbo);
325show_one(max_perf_pct, max_perf_pct);
326show_one(min_perf_pct, min_perf_pct);
327
328define_one_global_rw(no_turbo);
329define_one_global_rw(max_perf_pct);
330define_one_global_rw(min_perf_pct);
331
332static struct attribute *intel_pstate_attributes[] = {
333 &no_turbo.attr,
334 &max_perf_pct.attr,
335 &min_perf_pct.attr,
336 NULL
337};
338
339static struct attribute_group intel_pstate_attr_group = {
340 .attrs = intel_pstate_attributes,
341};
342static struct kobject *intel_pstate_kobject;
343
344static void intel_pstate_sysfs_expose_params(void)
345{
346 int rc;
347
348 intel_pstate_kobject = kobject_create_and_add("intel_pstate",
349 &cpu_subsys.dev_root->kobj);
350 BUG_ON(!intel_pstate_kobject);
351 rc = sysfs_create_group(intel_pstate_kobject,
352 &intel_pstate_attr_group);
353 BUG_ON(rc);
354}
355
356/************************** sysfs end ************************/
357
358static int intel_pstate_min_pstate(void)
359{
360 u64 value;
Konrad Rzeszutek Wilk05e99c8cf2013-03-20 14:21:10 +0000361 rdmsrl(MSR_PLATFORM_INFO, value);
Dirk Brandewie93f08222013-02-06 09:02:13 -0800362 return (value >> 40) & 0xFF;
363}
364
365static int intel_pstate_max_pstate(void)
366{
367 u64 value;
Konrad Rzeszutek Wilk05e99c8cf2013-03-20 14:21:10 +0000368 rdmsrl(MSR_PLATFORM_INFO, value);
Dirk Brandewie93f08222013-02-06 09:02:13 -0800369 return (value >> 8) & 0xFF;
370}
371
372static int intel_pstate_turbo_pstate(void)
373{
374 u64 value;
375 int nont, ret;
Konrad Rzeszutek Wilk05e99c8cf2013-03-20 14:21:10 +0000376 rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value);
Dirk Brandewie93f08222013-02-06 09:02:13 -0800377 nont = intel_pstate_max_pstate();
378 ret = ((value) & 255);
379 if (ret <= nont)
380 ret = nont;
381 return ret;
382}
383
384static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max)
385{
386 int max_perf = cpu->pstate.turbo_pstate;
387 int min_perf;
388 if (limits.no_turbo)
389 max_perf = cpu->pstate.max_pstate;
390
391 max_perf = fp_toint(mul_fp(int_tofp(max_perf), limits.max_perf));
392 *max = clamp_t(int, max_perf,
393 cpu->pstate.min_pstate, cpu->pstate.turbo_pstate);
394
395 min_perf = fp_toint(mul_fp(int_tofp(max_perf), limits.min_perf));
396 *min = clamp_t(int, min_perf,
397 cpu->pstate.min_pstate, max_perf);
398}
399
400static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate)
401{
402 int max_perf, min_perf;
403
404 intel_pstate_get_min_max(cpu, &min_perf, &max_perf);
405
406 pstate = clamp_t(int, pstate, min_perf, max_perf);
407
408 if (pstate == cpu->pstate.current_pstate)
409 return;
410
411#ifndef MODULE
412 trace_cpu_frequency(pstate * 100000, cpu->cpu);
413#endif
414 cpu->pstate.current_pstate = pstate;
415 wrmsrl(MSR_IA32_PERF_CTL, pstate << 8);
416
417}
418
419static inline void intel_pstate_pstate_increase(struct cpudata *cpu, int steps)
420{
421 int target;
422 target = cpu->pstate.current_pstate + steps;
423
424 intel_pstate_set_pstate(cpu, target);
425}
426
427static inline void intel_pstate_pstate_decrease(struct cpudata *cpu, int steps)
428{
429 int target;
430 target = cpu->pstate.current_pstate - steps;
431 intel_pstate_set_pstate(cpu, target);
432}
433
434static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
435{
436 sprintf(cpu->name, "Intel 2nd generation core");
437
438 cpu->pstate.min_pstate = intel_pstate_min_pstate();
439 cpu->pstate.max_pstate = intel_pstate_max_pstate();
440 cpu->pstate.turbo_pstate = intel_pstate_turbo_pstate();
441
442 /*
443 * goto max pstate so we don't slow up boot if we are built-in if we are
444 * a module we will take care of it during normal operation
445 */
446 intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate);
447}
448
449static inline void intel_pstate_calc_busy(struct cpudata *cpu,
450 struct sample *sample)
451{
452 u64 core_pct;
453 sample->pstate_pct_busy = 100 - div64_u64(
454 sample->idletime_us * 100,
455 sample->duration_us);
456 core_pct = div64_u64(sample->aperf * 100, sample->mperf);
Dirk Brandewiee6f3eb22013-03-24 00:54:39 +0100457 sample->freq = cpu->pstate.max_pstate * core_pct * 1000;
Dirk Brandewie93f08222013-02-06 09:02:13 -0800458
Dirk Brandewie191e5ed2013-02-11 20:33:34 +0100459 sample->core_pct_busy = div_s64((sample->pstate_pct_busy * core_pct),
460 100);
Dirk Brandewie93f08222013-02-06 09:02:13 -0800461}
462
463static inline void intel_pstate_sample(struct cpudata *cpu)
464{
465 ktime_t now;
466 u64 idle_time_us;
467 u64 aperf, mperf;
468
469 now = ktime_get();
470 idle_time_us = get_cpu_idle_time_us(cpu->cpu, NULL);
471
472 rdmsrl(MSR_IA32_APERF, aperf);
473 rdmsrl(MSR_IA32_MPERF, mperf);
474 /* for the first sample, don't actually record a sample, just
475 * set the baseline */
476 if (cpu->prev_idle_time_us > 0) {
477 cpu->sample_ptr = (cpu->sample_ptr + 1) % SAMPLE_COUNT;
478 cpu->samples[cpu->sample_ptr].start_time = cpu->prev_sample;
479 cpu->samples[cpu->sample_ptr].end_time = now;
480 cpu->samples[cpu->sample_ptr].duration_us =
481 ktime_us_delta(now, cpu->prev_sample);
482 cpu->samples[cpu->sample_ptr].idletime_us =
483 idle_time_us - cpu->prev_idle_time_us;
484
485 cpu->samples[cpu->sample_ptr].aperf = aperf;
486 cpu->samples[cpu->sample_ptr].mperf = mperf;
487 cpu->samples[cpu->sample_ptr].aperf -= cpu->prev_aperf;
488 cpu->samples[cpu->sample_ptr].mperf -= cpu->prev_mperf;
489
490 intel_pstate_calc_busy(cpu, &cpu->samples[cpu->sample_ptr]);
491 }
492
493 cpu->prev_sample = now;
494 cpu->prev_idle_time_us = idle_time_us;
495 cpu->prev_aperf = aperf;
496 cpu->prev_mperf = mperf;
497}
498
499static inline void intel_pstate_set_sample_time(struct cpudata *cpu)
500{
501 int sample_time, delay;
502
503 sample_time = cpu->pstate_policy->sample_rate_ms;
504 delay = msecs_to_jiffies(sample_time);
Dirk Brandewie93f08222013-02-06 09:02:13 -0800505 mod_timer_pinned(&cpu->timer, jiffies + delay);
506}
507
508static inline void intel_pstate_idle_mode(struct cpudata *cpu)
509{
510 cpu->idle_mode = 1;
511}
512
513static inline void intel_pstate_normal_mode(struct cpudata *cpu)
514{
515 cpu->idle_mode = 0;
516}
517
518static inline int intel_pstate_get_scaled_busy(struct cpudata *cpu)
519{
520 int32_t busy_scaled;
521 int32_t core_busy, turbo_pstate, current_pstate;
522
523 core_busy = int_tofp(cpu->samples[cpu->sample_ptr].core_pct_busy);
524 turbo_pstate = int_tofp(cpu->pstate.turbo_pstate);
525 current_pstate = int_tofp(cpu->pstate.current_pstate);
526 busy_scaled = mul_fp(core_busy, div_fp(turbo_pstate, current_pstate));
527
528 return fp_toint(busy_scaled);
529}
530
531static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
532{
533 int busy_scaled;
534 struct _pid *pid;
535 signed int ctl = 0;
536 int steps;
537
538 pid = &cpu->pid;
539 busy_scaled = intel_pstate_get_scaled_busy(cpu);
540
541 ctl = pid_calc(pid, busy_scaled);
542
543 steps = abs(ctl);
544 if (ctl < 0)
545 intel_pstate_pstate_increase(cpu, steps);
546 else
547 intel_pstate_pstate_decrease(cpu, steps);
548}
549
550static inline void intel_pstate_adjust_idle_pstate(struct cpudata *cpu)
551{
552 int busy_scaled;
553 struct _pid *pid;
554 int ctl = 0;
555 int steps;
556
557 pid = &cpu->idle_pid;
558
559 busy_scaled = intel_pstate_get_scaled_busy(cpu);
560
561 ctl = pid_calc(pid, 100 - busy_scaled);
562
563 steps = abs(ctl);
564 if (ctl < 0)
565 intel_pstate_pstate_decrease(cpu, steps);
566 else
567 intel_pstate_pstate_increase(cpu, steps);
568
569 if (cpu->pstate.current_pstate == cpu->pstate.min_pstate)
570 intel_pstate_normal_mode(cpu);
571}
572
573static void intel_pstate_timer_func(unsigned long __data)
574{
575 struct cpudata *cpu = (struct cpudata *) __data;
576
577 intel_pstate_sample(cpu);
578
579 if (!cpu->idle_mode)
580 intel_pstate_adjust_busy_pstate(cpu);
581 else
582 intel_pstate_adjust_idle_pstate(cpu);
583
584#if defined(XPERF_FIX)
585 if (cpu->pstate.current_pstate == cpu->pstate.min_pstate) {
586 cpu->min_pstate_count++;
587 if (!(cpu->min_pstate_count % 5)) {
588 intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate);
589 intel_pstate_idle_mode(cpu);
590 }
591 } else
592 cpu->min_pstate_count = 0;
593#endif
594 intel_pstate_set_sample_time(cpu);
595}
596
597#define ICPU(model, policy) \
598 { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, (unsigned long)&policy }
599
600static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
601 ICPU(0x2a, default_policy),
602 ICPU(0x2d, default_policy),
603 {}
604};
605MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
606
607static int intel_pstate_init_cpu(unsigned int cpunum)
608{
609
610 const struct x86_cpu_id *id;
611 struct cpudata *cpu;
612
613 id = x86_match_cpu(intel_pstate_cpu_ids);
614 if (!id)
615 return -ENODEV;
616
617 all_cpu_data[cpunum] = kzalloc(sizeof(struct cpudata), GFP_KERNEL);
618 if (!all_cpu_data[cpunum])
619 return -ENOMEM;
620
621 cpu = all_cpu_data[cpunum];
622
623 intel_pstate_get_cpu_pstates(cpu);
624
625 cpu->cpu = cpunum;
626 cpu->pstate_policy =
627 (struct pstate_adjust_policy *)id->driver_data;
628 init_timer_deferrable(&cpu->timer);
629 cpu->timer.function = intel_pstate_timer_func;
630 cpu->timer.data =
631 (unsigned long)cpu;
632 cpu->timer.expires = jiffies + HZ/100;
633 intel_pstate_busy_pid_reset(cpu);
634 intel_pstate_idle_pid_reset(cpu);
635 intel_pstate_sample(cpu);
636 intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate);
637
638 add_timer_on(&cpu->timer, cpunum);
639
640 pr_info("Intel pstate controlling: cpu %d\n", cpunum);
641
642 return 0;
643}
644
645static unsigned int intel_pstate_get(unsigned int cpu_num)
646{
647 struct sample *sample;
648 struct cpudata *cpu;
649
650 cpu = all_cpu_data[cpu_num];
651 if (!cpu)
652 return 0;
653 sample = &cpu->samples[cpu->sample_ptr];
654 return sample->freq;
655}
656
657static int intel_pstate_set_policy(struct cpufreq_policy *policy)
658{
659 struct cpudata *cpu;
Dirk Brandewie93f08222013-02-06 09:02:13 -0800660
661 cpu = all_cpu_data[policy->cpu];
662
Dirk Brandewied3929b82013-03-05 14:15:26 -0800663 if (!policy->cpuinfo.max_freq)
664 return -ENODEV;
665
Dirk Brandewie93f08222013-02-06 09:02:13 -0800666 if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) {
667 limits.min_perf_pct = 100;
668 limits.min_perf = int_tofp(1);
669 limits.max_perf_pct = 100;
670 limits.max_perf = int_tofp(1);
671 limits.no_turbo = 0;
Srinivas Pandruvadad1b68482013-04-09 22:38:18 +0000672 return 0;
Dirk Brandewie93f08222013-02-06 09:02:13 -0800673 }
Srinivas Pandruvadad1b68482013-04-09 22:38:18 +0000674 limits.min_perf_pct = (policy->min * 100) / policy->cpuinfo.max_freq;
675 limits.min_perf_pct = clamp_t(int, limits.min_perf_pct, 0 , 100);
676 limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
677
678 limits.max_perf_pct = policy->max * 100 / policy->cpuinfo.max_freq;
679 limits.max_perf_pct = clamp_t(int, limits.max_perf_pct, 0 , 100);
680 limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
Dirk Brandewie93f08222013-02-06 09:02:13 -0800681
682 return 0;
683}
684
685static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
686{
687 cpufreq_verify_within_limits(policy,
688 policy->cpuinfo.min_freq,
689 policy->cpuinfo.max_freq);
690
691 if ((policy->policy != CPUFREQ_POLICY_POWERSAVE) &&
692 (policy->policy != CPUFREQ_POLICY_PERFORMANCE))
693 return -EINVAL;
694
695 return 0;
696}
697
698static int __cpuinit intel_pstate_cpu_exit(struct cpufreq_policy *policy)
699{
700 int cpu = policy->cpu;
701
702 del_timer(&all_cpu_data[cpu]->timer);
703 kfree(all_cpu_data[cpu]);
704 all_cpu_data[cpu] = NULL;
705 return 0;
706}
707
708static int __cpuinit intel_pstate_cpu_init(struct cpufreq_policy *policy)
709{
710 int rc, min_pstate, max_pstate;
711 struct cpudata *cpu;
712
713 rc = intel_pstate_init_cpu(policy->cpu);
714 if (rc)
715 return rc;
716
717 cpu = all_cpu_data[policy->cpu];
718
719 if (!limits.no_turbo &&
720 limits.min_perf_pct == 100 && limits.max_perf_pct == 100)
721 policy->policy = CPUFREQ_POLICY_PERFORMANCE;
722 else
723 policy->policy = CPUFREQ_POLICY_POWERSAVE;
724
725 intel_pstate_get_min_max(cpu, &min_pstate, &max_pstate);
726 policy->min = min_pstate * 100000;
727 policy->max = max_pstate * 100000;
728
729 /* cpuinfo and default policy values */
730 policy->cpuinfo.min_freq = cpu->pstate.min_pstate * 100000;
731 policy->cpuinfo.max_freq = cpu->pstate.turbo_pstate * 100000;
732 policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
733 cpumask_set_cpu(policy->cpu, policy->cpus);
734
735 return 0;
736}
737
738static struct cpufreq_driver intel_pstate_driver = {
739 .flags = CPUFREQ_CONST_LOOPS,
740 .verify = intel_pstate_verify_policy,
741 .setpolicy = intel_pstate_set_policy,
742 .get = intel_pstate_get,
743 .init = intel_pstate_cpu_init,
744 .exit = intel_pstate_cpu_exit,
745 .name = "intel_pstate",
746 .owner = THIS_MODULE,
747};
748
Dirk Brandewie6be26492013-02-15 22:55:10 +0100749static int __initdata no_load;
750
Dirk Brandewieb563b4e2013-03-22 01:29:28 +0100751static int intel_pstate_msrs_not_valid(void)
752{
753 /* Check that all the msr's we are using are valid. */
754 u64 aperf, mperf, tmp;
755
756 rdmsrl(MSR_IA32_APERF, aperf);
757 rdmsrl(MSR_IA32_MPERF, mperf);
758
759 if (!intel_pstate_min_pstate() ||
760 !intel_pstate_max_pstate() ||
761 !intel_pstate_turbo_pstate())
762 return -ENODEV;
763
764 rdmsrl(MSR_IA32_APERF, tmp);
765 if (!(tmp - aperf))
766 return -ENODEV;
767
768 rdmsrl(MSR_IA32_MPERF, tmp);
769 if (!(tmp - mperf))
770 return -ENODEV;
771
772 return 0;
773}
Dirk Brandewie93f08222013-02-06 09:02:13 -0800774static int __init intel_pstate_init(void)
775{
Dirk Brandewie907cc902013-03-05 14:15:27 -0800776 int cpu, rc = 0;
Dirk Brandewie93f08222013-02-06 09:02:13 -0800777 const struct x86_cpu_id *id;
778
Dirk Brandewie6be26492013-02-15 22:55:10 +0100779 if (no_load)
780 return -ENODEV;
781
Dirk Brandewie93f08222013-02-06 09:02:13 -0800782 id = x86_match_cpu(intel_pstate_cpu_ids);
783 if (!id)
784 return -ENODEV;
785
Dirk Brandewieb563b4e2013-03-22 01:29:28 +0100786 if (intel_pstate_msrs_not_valid())
787 return -ENODEV;
788
Dirk Brandewie93f08222013-02-06 09:02:13 -0800789 pr_info("Intel P-state driver initializing.\n");
790
791 all_cpu_data = vmalloc(sizeof(void *) * num_possible_cpus());
792 if (!all_cpu_data)
793 return -ENOMEM;
794 memset(all_cpu_data, 0, sizeof(void *) * num_possible_cpus());
795
796 rc = cpufreq_register_driver(&intel_pstate_driver);
797 if (rc)
798 goto out;
799
800 intel_pstate_debug_expose_params();
801 intel_pstate_sysfs_expose_params();
802 return rc;
803out:
Dirk Brandewie907cc902013-03-05 14:15:27 -0800804 get_online_cpus();
805 for_each_online_cpu(cpu) {
806 if (all_cpu_data[cpu]) {
807 del_timer_sync(&all_cpu_data[cpu]->timer);
808 kfree(all_cpu_data[cpu]);
809 }
810 }
811
812 put_online_cpus();
813 vfree(all_cpu_data);
Dirk Brandewie93f08222013-02-06 09:02:13 -0800814 return -ENODEV;
815}
816device_initcall(intel_pstate_init);
817
Dirk Brandewie6be26492013-02-15 22:55:10 +0100818static int __init intel_pstate_setup(char *str)
819{
820 if (!str)
821 return -EINVAL;
822
823 if (!strcmp(str, "disable"))
824 no_load = 1;
825 return 0;
826}
827early_param("intel_pstate", intel_pstate_setup);
828
Dirk Brandewie93f08222013-02-06 09:02:13 -0800829MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>");
830MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors");
831MODULE_LICENSE("GPL");