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[~andy/linux] / drivers / cpufreq / intel_pstate.c
1 /*
2  * intel_pstate.c: Native P state management for Intel processors
3  *
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 <linux/acpi.h>
29 #include <trace/events/power.h>
30
31 #include <asm/div64.h>
32 #include <asm/msr.h>
33 #include <asm/cpu_device_id.h>
34
35 #define SAMPLE_COUNT            3
36
37 #define BYT_RATIOS              0x66a
38 #define BYT_VIDS                0x66b
39 #define BYT_TURBO_RATIOS        0x66c
40
41
42 #define FRAC_BITS 6
43 #define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
44 #define fp_toint(X) ((X) >> FRAC_BITS)
45 #define FP_ROUNDUP(X) ((X) += 1 << FRAC_BITS)
46
47 static inline int32_t mul_fp(int32_t x, int32_t y)
48 {
49         return ((int64_t)x * (int64_t)y) >> FRAC_BITS;
50 }
51
52 static inline int32_t div_fp(int32_t x, int32_t y)
53 {
54         return div_s64((int64_t)x << FRAC_BITS, (int64_t)y);
55 }
56
57 struct sample {
58         int32_t core_pct_busy;
59         u64 aperf;
60         u64 mperf;
61         unsigned long long tsc;
62         int freq;
63 };
64
65 struct pstate_data {
66         int     current_pstate;
67         int     min_pstate;
68         int     max_pstate;
69         int     turbo_pstate;
70 };
71
72 struct vid_data {
73         int32_t min;
74         int32_t max;
75         int32_t ratio;
76 };
77
78 struct _pid {
79         int setpoint;
80         int32_t integral;
81         int32_t p_gain;
82         int32_t i_gain;
83         int32_t d_gain;
84         int deadband;
85         int32_t last_err;
86 };
87
88 struct cpudata {
89         int cpu;
90
91         char name[64];
92
93         struct timer_list timer;
94
95         struct pstate_data pstate;
96         struct vid_data vid;
97         struct _pid pid;
98
99         u64     prev_aperf;
100         u64     prev_mperf;
101         unsigned long long prev_tsc;
102         int     sample_ptr;
103         struct sample samples[SAMPLE_COUNT];
104 };
105
106 static struct cpudata **all_cpu_data;
107 struct pstate_adjust_policy {
108         int sample_rate_ms;
109         int deadband;
110         int setpoint;
111         int p_gain_pct;
112         int d_gain_pct;
113         int i_gain_pct;
114 };
115
116 struct pstate_funcs {
117         int (*get_max)(void);
118         int (*get_min)(void);
119         int (*get_turbo)(void);
120         void (*set)(struct cpudata*, int pstate);
121         void (*get_vid)(struct cpudata *);
122 };
123
124 struct cpu_defaults {
125         struct pstate_adjust_policy pid_policy;
126         struct pstate_funcs funcs;
127 };
128
129 static struct pstate_adjust_policy pid_params;
130 static struct pstate_funcs pstate_funcs;
131
132 struct perf_limits {
133         int no_turbo;
134         int max_perf_pct;
135         int min_perf_pct;
136         int32_t max_perf;
137         int32_t min_perf;
138         int max_policy_pct;
139         int max_sysfs_pct;
140 };
141
142 static struct perf_limits limits = {
143         .no_turbo = 0,
144         .max_perf_pct = 100,
145         .max_perf = int_tofp(1),
146         .min_perf_pct = 0,
147         .min_perf = 0,
148         .max_policy_pct = 100,
149         .max_sysfs_pct = 100,
150 };
151
152 static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
153                         int deadband, int integral) {
154         pid->setpoint = setpoint;
155         pid->deadband  = deadband;
156         pid->integral  = int_tofp(integral);
157         pid->last_err  = setpoint - busy;
158 }
159
160 static inline void pid_p_gain_set(struct _pid *pid, int percent)
161 {
162         pid->p_gain = div_fp(int_tofp(percent), int_tofp(100));
163 }
164
165 static inline void pid_i_gain_set(struct _pid *pid, int percent)
166 {
167         pid->i_gain = div_fp(int_tofp(percent), int_tofp(100));
168 }
169
170 static inline void pid_d_gain_set(struct _pid *pid, int percent)
171 {
172
173         pid->d_gain = div_fp(int_tofp(percent), int_tofp(100));
174 }
175
176 static signed int pid_calc(struct _pid *pid, int32_t busy)
177 {
178         signed int result;
179         int32_t pterm, dterm, fp_error;
180         int32_t integral_limit;
181
182         fp_error = int_tofp(pid->setpoint) - busy;
183
184         if (abs(fp_error) <= int_tofp(pid->deadband))
185                 return 0;
186
187         pterm = mul_fp(pid->p_gain, fp_error);
188
189         pid->integral += fp_error;
190
191         /* limit the integral term */
192         integral_limit = int_tofp(30);
193         if (pid->integral > integral_limit)
194                 pid->integral = integral_limit;
195         if (pid->integral < -integral_limit)
196                 pid->integral = -integral_limit;
197
198         dterm = mul_fp(pid->d_gain, fp_error - pid->last_err);
199         pid->last_err = fp_error;
200
201         result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm;
202
203         return (signed int)fp_toint(result);
204 }
205
206 static inline void intel_pstate_busy_pid_reset(struct cpudata *cpu)
207 {
208         pid_p_gain_set(&cpu->pid, pid_params.p_gain_pct);
209         pid_d_gain_set(&cpu->pid, pid_params.d_gain_pct);
210         pid_i_gain_set(&cpu->pid, pid_params.i_gain_pct);
211
212         pid_reset(&cpu->pid,
213                 pid_params.setpoint,
214                 100,
215                 pid_params.deadband,
216                 0);
217 }
218
219 static inline void intel_pstate_reset_all_pid(void)
220 {
221         unsigned int cpu;
222         for_each_online_cpu(cpu) {
223                 if (all_cpu_data[cpu])
224                         intel_pstate_busy_pid_reset(all_cpu_data[cpu]);
225         }
226 }
227
228 /************************** debugfs begin ************************/
229 static int pid_param_set(void *data, u64 val)
230 {
231         *(u32 *)data = val;
232         intel_pstate_reset_all_pid();
233         return 0;
234 }
235 static int pid_param_get(void *data, u64 *val)
236 {
237         *val = *(u32 *)data;
238         return 0;
239 }
240 DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get,
241                         pid_param_set, "%llu\n");
242
243 struct pid_param {
244         char *name;
245         void *value;
246 };
247
248 static struct pid_param pid_files[] = {
249         {"sample_rate_ms", &pid_params.sample_rate_ms},
250         {"d_gain_pct", &pid_params.d_gain_pct},
251         {"i_gain_pct", &pid_params.i_gain_pct},
252         {"deadband", &pid_params.deadband},
253         {"setpoint", &pid_params.setpoint},
254         {"p_gain_pct", &pid_params.p_gain_pct},
255         {NULL, NULL}
256 };
257
258 static struct dentry *debugfs_parent;
259 static void intel_pstate_debug_expose_params(void)
260 {
261         int i = 0;
262
263         debugfs_parent = debugfs_create_dir("pstate_snb", NULL);
264         if (IS_ERR_OR_NULL(debugfs_parent))
265                 return;
266         while (pid_files[i].name) {
267                 debugfs_create_file(pid_files[i].name, 0660,
268                                 debugfs_parent, pid_files[i].value,
269                                 &fops_pid_param);
270                 i++;
271         }
272 }
273
274 /************************** debugfs end ************************/
275
276 /************************** sysfs begin ************************/
277 #define show_one(file_name, object)                                     \
278         static ssize_t show_##file_name                                 \
279         (struct kobject *kobj, struct attribute *attr, char *buf)       \
280         {                                                               \
281                 return sprintf(buf, "%u\n", limits.object);             \
282         }
283
284 static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
285                                 const char *buf, size_t count)
286 {
287         unsigned int input;
288         int ret;
289         ret = sscanf(buf, "%u", &input);
290         if (ret != 1)
291                 return -EINVAL;
292         limits.no_turbo = clamp_t(int, input, 0 , 1);
293
294         return count;
295 }
296
297 static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
298                                 const char *buf, size_t count)
299 {
300         unsigned int input;
301         int ret;
302         ret = sscanf(buf, "%u", &input);
303         if (ret != 1)
304                 return -EINVAL;
305
306         limits.max_sysfs_pct = clamp_t(int, input, 0 , 100);
307         limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct);
308         limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
309         return count;
310 }
311
312 static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
313                                 const char *buf, size_t count)
314 {
315         unsigned int input;
316         int ret;
317         ret = sscanf(buf, "%u", &input);
318         if (ret != 1)
319                 return -EINVAL;
320         limits.min_perf_pct = clamp_t(int, input, 0 , 100);
321         limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
322
323         return count;
324 }
325
326 show_one(no_turbo, no_turbo);
327 show_one(max_perf_pct, max_perf_pct);
328 show_one(min_perf_pct, min_perf_pct);
329
330 define_one_global_rw(no_turbo);
331 define_one_global_rw(max_perf_pct);
332 define_one_global_rw(min_perf_pct);
333
334 static struct attribute *intel_pstate_attributes[] = {
335         &no_turbo.attr,
336         &max_perf_pct.attr,
337         &min_perf_pct.attr,
338         NULL
339 };
340
341 static struct attribute_group intel_pstate_attr_group = {
342         .attrs = intel_pstate_attributes,
343 };
344 static struct kobject *intel_pstate_kobject;
345
346 static void intel_pstate_sysfs_expose_params(void)
347 {
348         int rc;
349
350         intel_pstate_kobject = kobject_create_and_add("intel_pstate",
351                                                 &cpu_subsys.dev_root->kobj);
352         BUG_ON(!intel_pstate_kobject);
353         rc = sysfs_create_group(intel_pstate_kobject,
354                                 &intel_pstate_attr_group);
355         BUG_ON(rc);
356 }
357
358 /************************** sysfs end ************************/
359 static int byt_get_min_pstate(void)
360 {
361         u64 value;
362         rdmsrl(BYT_RATIOS, value);
363         return (value >> 8) & 0xFF;
364 }
365
366 static int byt_get_max_pstate(void)
367 {
368         u64 value;
369         rdmsrl(BYT_RATIOS, value);
370         return (value >> 16) & 0xFF;
371 }
372
373 static int byt_get_turbo_pstate(void)
374 {
375         u64 value;
376         rdmsrl(BYT_TURBO_RATIOS, value);
377         return value & 0x3F;
378 }
379
380 static void byt_set_pstate(struct cpudata *cpudata, int pstate)
381 {
382         u64 val;
383         int32_t vid_fp;
384         u32 vid;
385
386         val = pstate << 8;
387         if (limits.no_turbo)
388                 val |= (u64)1 << 32;
389
390         vid_fp = cpudata->vid.min + mul_fp(
391                 int_tofp(pstate - cpudata->pstate.min_pstate),
392                 cpudata->vid.ratio);
393
394         vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
395         vid = fp_toint(vid_fp);
396
397         val |= vid;
398
399         wrmsrl(MSR_IA32_PERF_CTL, val);
400 }
401
402 static void byt_get_vid(struct cpudata *cpudata)
403 {
404         u64 value;
405
406         rdmsrl(BYT_VIDS, value);
407         cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
408         cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
409         cpudata->vid.ratio = div_fp(
410                 cpudata->vid.max - cpudata->vid.min,
411                 int_tofp(cpudata->pstate.max_pstate -
412                         cpudata->pstate.min_pstate));
413 }
414
415
416 static int core_get_min_pstate(void)
417 {
418         u64 value;
419         rdmsrl(MSR_PLATFORM_INFO, value);
420         return (value >> 40) & 0xFF;
421 }
422
423 static int core_get_max_pstate(void)
424 {
425         u64 value;
426         rdmsrl(MSR_PLATFORM_INFO, value);
427         return (value >> 8) & 0xFF;
428 }
429
430 static int core_get_turbo_pstate(void)
431 {
432         u64 value;
433         int nont, ret;
434         rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value);
435         nont = core_get_max_pstate();
436         ret = ((value) & 255);
437         if (ret <= nont)
438                 ret = nont;
439         return ret;
440 }
441
442 static void core_set_pstate(struct cpudata *cpudata, int pstate)
443 {
444         u64 val;
445
446         val = pstate << 8;
447         if (limits.no_turbo)
448                 val |= (u64)1 << 32;
449
450         wrmsrl(MSR_IA32_PERF_CTL, val);
451 }
452
453 static struct cpu_defaults core_params = {
454         .pid_policy = {
455                 .sample_rate_ms = 10,
456                 .deadband = 0,
457                 .setpoint = 97,
458                 .p_gain_pct = 20,
459                 .d_gain_pct = 0,
460                 .i_gain_pct = 0,
461         },
462         .funcs = {
463                 .get_max = core_get_max_pstate,
464                 .get_min = core_get_min_pstate,
465                 .get_turbo = core_get_turbo_pstate,
466                 .set = core_set_pstate,
467         },
468 };
469
470 static struct cpu_defaults byt_params = {
471         .pid_policy = {
472                 .sample_rate_ms = 10,
473                 .deadband = 0,
474                 .setpoint = 97,
475                 .p_gain_pct = 14,
476                 .d_gain_pct = 0,
477                 .i_gain_pct = 4,
478         },
479         .funcs = {
480                 .get_max = byt_get_max_pstate,
481                 .get_min = byt_get_min_pstate,
482                 .get_turbo = byt_get_turbo_pstate,
483                 .set = byt_set_pstate,
484                 .get_vid = byt_get_vid,
485         },
486 };
487
488
489 static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max)
490 {
491         int max_perf = cpu->pstate.turbo_pstate;
492         int max_perf_adj;
493         int min_perf;
494         if (limits.no_turbo)
495                 max_perf = cpu->pstate.max_pstate;
496
497         max_perf_adj = fp_toint(mul_fp(int_tofp(max_perf), limits.max_perf));
498         *max = clamp_t(int, max_perf_adj,
499                         cpu->pstate.min_pstate, cpu->pstate.turbo_pstate);
500
501         min_perf = fp_toint(mul_fp(int_tofp(max_perf), limits.min_perf));
502         *min = clamp_t(int, min_perf,
503                         cpu->pstate.min_pstate, max_perf);
504 }
505
506 static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate)
507 {
508         int max_perf, min_perf;
509
510         intel_pstate_get_min_max(cpu, &min_perf, &max_perf);
511
512         pstate = clamp_t(int, pstate, min_perf, max_perf);
513
514         if (pstate == cpu->pstate.current_pstate)
515                 return;
516
517         trace_cpu_frequency(pstate * 100000, cpu->cpu);
518
519         cpu->pstate.current_pstate = pstate;
520
521         pstate_funcs.set(cpu, pstate);
522 }
523
524 static inline void intel_pstate_pstate_increase(struct cpudata *cpu, int steps)
525 {
526         int target;
527         target = cpu->pstate.current_pstate + steps;
528
529         intel_pstate_set_pstate(cpu, target);
530 }
531
532 static inline void intel_pstate_pstate_decrease(struct cpudata *cpu, int steps)
533 {
534         int target;
535         target = cpu->pstate.current_pstate - steps;
536         intel_pstate_set_pstate(cpu, target);
537 }
538
539 static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
540 {
541         sprintf(cpu->name, "Intel 2nd generation core");
542
543         cpu->pstate.min_pstate = pstate_funcs.get_min();
544         cpu->pstate.max_pstate = pstate_funcs.get_max();
545         cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
546
547         if (pstate_funcs.get_vid)
548                 pstate_funcs.get_vid(cpu);
549
550         /*
551          * goto max pstate so we don't slow up boot if we are built-in if we are
552          * a module we will take care of it during normal operation
553          */
554         intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate);
555 }
556
557 static inline void intel_pstate_calc_busy(struct cpudata *cpu,
558                                         struct sample *sample)
559 {
560         int32_t core_pct;
561         int32_t c0_pct;
562
563         core_pct = div_fp(int_tofp((sample->aperf)),
564                         int_tofp((sample->mperf)));
565         core_pct = mul_fp(core_pct, int_tofp(100));
566         FP_ROUNDUP(core_pct);
567
568         c0_pct = div_fp(int_tofp(sample->mperf), int_tofp(sample->tsc));
569
570         sample->freq = fp_toint(
571                 mul_fp(int_tofp(cpu->pstate.max_pstate * 1000), core_pct));
572
573         sample->core_pct_busy = mul_fp(core_pct, c0_pct);
574 }
575
576 static inline void intel_pstate_sample(struct cpudata *cpu)
577 {
578         u64 aperf, mperf;
579         unsigned long long tsc;
580
581         rdmsrl(MSR_IA32_APERF, aperf);
582         rdmsrl(MSR_IA32_MPERF, mperf);
583         tsc = native_read_tsc();
584
585         aperf = aperf >> FRAC_BITS;
586         mperf = mperf >> FRAC_BITS;
587         tsc = tsc >> FRAC_BITS;
588
589         cpu->sample_ptr = (cpu->sample_ptr + 1) % SAMPLE_COUNT;
590         cpu->samples[cpu->sample_ptr].aperf = aperf;
591         cpu->samples[cpu->sample_ptr].mperf = mperf;
592         cpu->samples[cpu->sample_ptr].tsc = tsc;
593         cpu->samples[cpu->sample_ptr].aperf -= cpu->prev_aperf;
594         cpu->samples[cpu->sample_ptr].mperf -= cpu->prev_mperf;
595         cpu->samples[cpu->sample_ptr].tsc -= cpu->prev_tsc;
596
597         intel_pstate_calc_busy(cpu, &cpu->samples[cpu->sample_ptr]);
598
599         cpu->prev_aperf = aperf;
600         cpu->prev_mperf = mperf;
601         cpu->prev_tsc = tsc;
602 }
603
604 static inline void intel_pstate_set_sample_time(struct cpudata *cpu)
605 {
606         int sample_time, delay;
607
608         sample_time = pid_params.sample_rate_ms;
609         delay = msecs_to_jiffies(sample_time);
610         mod_timer_pinned(&cpu->timer, jiffies + delay);
611 }
612
613 static inline int32_t intel_pstate_get_scaled_busy(struct cpudata *cpu)
614 {
615         int32_t core_busy, max_pstate, current_pstate;
616
617         core_busy = cpu->samples[cpu->sample_ptr].core_pct_busy;
618         max_pstate = int_tofp(cpu->pstate.max_pstate);
619         current_pstate = int_tofp(cpu->pstate.current_pstate);
620         core_busy = mul_fp(core_busy, div_fp(max_pstate, current_pstate));
621         return FP_ROUNDUP(core_busy);
622 }
623
624 static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
625 {
626         int32_t busy_scaled;
627         struct _pid *pid;
628         signed int ctl = 0;
629         int steps;
630
631         pid = &cpu->pid;
632         busy_scaled = intel_pstate_get_scaled_busy(cpu);
633
634         ctl = pid_calc(pid, busy_scaled);
635
636         steps = abs(ctl);
637
638         if (ctl < 0)
639                 intel_pstate_pstate_increase(cpu, steps);
640         else
641                 intel_pstate_pstate_decrease(cpu, steps);
642 }
643
644 static void intel_pstate_timer_func(unsigned long __data)
645 {
646         struct cpudata *cpu = (struct cpudata *) __data;
647         struct sample *sample;
648
649         intel_pstate_sample(cpu);
650
651         sample = &cpu->samples[cpu->sample_ptr];
652
653         intel_pstate_adjust_busy_pstate(cpu);
654
655         trace_pstate_sample(fp_toint(sample->core_pct_busy),
656                         fp_toint(intel_pstate_get_scaled_busy(cpu)),
657                         cpu->pstate.current_pstate,
658                         sample->mperf,
659                         sample->aperf,
660                         sample->freq);
661
662         intel_pstate_set_sample_time(cpu);
663 }
664
665 #define ICPU(model, policy) \
666         { X86_VENDOR_INTEL, 6, model, X86_FEATURE_APERFMPERF,\
667                         (unsigned long)&policy }
668
669 static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
670         ICPU(0x2a, core_params),
671         ICPU(0x2d, core_params),
672         ICPU(0x37, byt_params),
673         ICPU(0x3a, core_params),
674         ICPU(0x3c, core_params),
675         ICPU(0x3e, core_params),
676         ICPU(0x3f, core_params),
677         ICPU(0x45, core_params),
678         ICPU(0x46, core_params),
679         {}
680 };
681 MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
682
683 static int intel_pstate_init_cpu(unsigned int cpunum)
684 {
685
686         const struct x86_cpu_id *id;
687         struct cpudata *cpu;
688
689         id = x86_match_cpu(intel_pstate_cpu_ids);
690         if (!id)
691                 return -ENODEV;
692
693         all_cpu_data[cpunum] = kzalloc(sizeof(struct cpudata), GFP_KERNEL);
694         if (!all_cpu_data[cpunum])
695                 return -ENOMEM;
696
697         cpu = all_cpu_data[cpunum];
698
699         intel_pstate_get_cpu_pstates(cpu);
700         if (!cpu->pstate.current_pstate) {
701                 all_cpu_data[cpunum] = NULL;
702                 kfree(cpu);
703                 return -ENODATA;
704         }
705
706         cpu->cpu = cpunum;
707
708         init_timer_deferrable(&cpu->timer);
709         cpu->timer.function = intel_pstate_timer_func;
710         cpu->timer.data =
711                 (unsigned long)cpu;
712         cpu->timer.expires = jiffies + HZ/100;
713         intel_pstate_busy_pid_reset(cpu);
714         intel_pstate_sample(cpu);
715         intel_pstate_set_pstate(cpu, cpu->pstate.max_pstate);
716
717         add_timer_on(&cpu->timer, cpunum);
718
719         pr_info("Intel pstate controlling: cpu %d\n", cpunum);
720
721         return 0;
722 }
723
724 static unsigned int intel_pstate_get(unsigned int cpu_num)
725 {
726         struct sample *sample;
727         struct cpudata *cpu;
728
729         cpu = all_cpu_data[cpu_num];
730         if (!cpu)
731                 return 0;
732         sample = &cpu->samples[cpu->sample_ptr];
733         return sample->freq;
734 }
735
736 static int intel_pstate_set_policy(struct cpufreq_policy *policy)
737 {
738         struct cpudata *cpu;
739
740         cpu = all_cpu_data[policy->cpu];
741
742         if (!policy->cpuinfo.max_freq)
743                 return -ENODEV;
744
745         if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) {
746                 limits.min_perf_pct = 100;
747                 limits.min_perf = int_tofp(1);
748                 limits.max_perf_pct = 100;
749                 limits.max_perf = int_tofp(1);
750                 limits.no_turbo = 0;
751                 return 0;
752         }
753         limits.min_perf_pct = (policy->min * 100) / policy->cpuinfo.max_freq;
754         limits.min_perf_pct = clamp_t(int, limits.min_perf_pct, 0 , 100);
755         limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100));
756
757         limits.max_policy_pct = policy->max * 100 / policy->cpuinfo.max_freq;
758         limits.max_policy_pct = clamp_t(int, limits.max_policy_pct, 0 , 100);
759         limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct);
760         limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100));
761
762         return 0;
763 }
764
765 static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
766 {
767         cpufreq_verify_within_cpu_limits(policy);
768
769         if ((policy->policy != CPUFREQ_POLICY_POWERSAVE) &&
770                 (policy->policy != CPUFREQ_POLICY_PERFORMANCE))
771                 return -EINVAL;
772
773         return 0;
774 }
775
776 static int intel_pstate_cpu_exit(struct cpufreq_policy *policy)
777 {
778         int cpu = policy->cpu;
779
780         del_timer(&all_cpu_data[cpu]->timer);
781         kfree(all_cpu_data[cpu]);
782         all_cpu_data[cpu] = NULL;
783         return 0;
784 }
785
786 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
787 {
788         struct cpudata *cpu;
789         int rc;
790
791         rc = intel_pstate_init_cpu(policy->cpu);
792         if (rc)
793                 return rc;
794
795         cpu = all_cpu_data[policy->cpu];
796
797         if (!limits.no_turbo &&
798                 limits.min_perf_pct == 100 && limits.max_perf_pct == 100)
799                 policy->policy = CPUFREQ_POLICY_PERFORMANCE;
800         else
801                 policy->policy = CPUFREQ_POLICY_POWERSAVE;
802
803         policy->min = cpu->pstate.min_pstate * 100000;
804         policy->max = cpu->pstate.turbo_pstate * 100000;
805
806         /* cpuinfo and default policy values */
807         policy->cpuinfo.min_freq = cpu->pstate.min_pstate * 100000;
808         policy->cpuinfo.max_freq = cpu->pstate.turbo_pstate * 100000;
809         policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
810         cpumask_set_cpu(policy->cpu, policy->cpus);
811
812         return 0;
813 }
814
815 static struct cpufreq_driver intel_pstate_driver = {
816         .flags          = CPUFREQ_CONST_LOOPS,
817         .verify         = intel_pstate_verify_policy,
818         .setpolicy      = intel_pstate_set_policy,
819         .get            = intel_pstate_get,
820         .init           = intel_pstate_cpu_init,
821         .exit           = intel_pstate_cpu_exit,
822         .name           = "intel_pstate",
823 };
824
825 static int __initdata no_load;
826
827 static int intel_pstate_msrs_not_valid(void)
828 {
829         /* Check that all the msr's we are using are valid. */
830         u64 aperf, mperf, tmp;
831
832         rdmsrl(MSR_IA32_APERF, aperf);
833         rdmsrl(MSR_IA32_MPERF, mperf);
834
835         if (!pstate_funcs.get_max() ||
836                 !pstate_funcs.get_min() ||
837                 !pstate_funcs.get_turbo())
838                 return -ENODEV;
839
840         rdmsrl(MSR_IA32_APERF, tmp);
841         if (!(tmp - aperf))
842                 return -ENODEV;
843
844         rdmsrl(MSR_IA32_MPERF, tmp);
845         if (!(tmp - mperf))
846                 return -ENODEV;
847
848         return 0;
849 }
850
851 static void copy_pid_params(struct pstate_adjust_policy *policy)
852 {
853         pid_params.sample_rate_ms = policy->sample_rate_ms;
854         pid_params.p_gain_pct = policy->p_gain_pct;
855         pid_params.i_gain_pct = policy->i_gain_pct;
856         pid_params.d_gain_pct = policy->d_gain_pct;
857         pid_params.deadband = policy->deadband;
858         pid_params.setpoint = policy->setpoint;
859 }
860
861 static void copy_cpu_funcs(struct pstate_funcs *funcs)
862 {
863         pstate_funcs.get_max   = funcs->get_max;
864         pstate_funcs.get_min   = funcs->get_min;
865         pstate_funcs.get_turbo = funcs->get_turbo;
866         pstate_funcs.set       = funcs->set;
867         pstate_funcs.get_vid   = funcs->get_vid;
868 }
869
870 #if IS_ENABLED(CONFIG_ACPI)
871 #include <acpi/processor.h>
872
873 static bool intel_pstate_no_acpi_pss(void)
874 {
875         int i;
876
877         for_each_possible_cpu(i) {
878                 acpi_status status;
879                 union acpi_object *pss;
880                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
881                 struct acpi_processor *pr = per_cpu(processors, i);
882
883                 if (!pr)
884                         continue;
885
886                 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
887                 if (ACPI_FAILURE(status))
888                         continue;
889
890                 pss = buffer.pointer;
891                 if (pss && pss->type == ACPI_TYPE_PACKAGE) {
892                         kfree(pss);
893                         return false;
894                 }
895
896                 kfree(pss);
897         }
898
899         return true;
900 }
901
902 struct hw_vendor_info {
903         u16  valid;
904         char oem_id[ACPI_OEM_ID_SIZE];
905         char oem_table_id[ACPI_OEM_TABLE_ID_SIZE];
906 };
907
908 /* Hardware vendor-specific info that has its own power management modes */
909 static struct hw_vendor_info vendor_info[] = {
910         {1, "HP    ", "ProLiant"},
911         {0, "", ""},
912 };
913
914 static bool intel_pstate_platform_pwr_mgmt_exists(void)
915 {
916         struct acpi_table_header hdr;
917         struct hw_vendor_info *v_info;
918
919         if (acpi_disabled
920             || ACPI_FAILURE(acpi_get_table_header(ACPI_SIG_FADT, 0, &hdr)))
921                 return false;
922
923         for (v_info = vendor_info; v_info->valid; v_info++) {
924                 if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE)
925                     && !strncmp(hdr.oem_table_id, v_info->oem_table_id, ACPI_OEM_TABLE_ID_SIZE)
926                     && intel_pstate_no_acpi_pss())
927                         return true;
928         }
929
930         return false;
931 }
932 #else /* CONFIG_ACPI not enabled */
933 static inline bool intel_pstate_platform_pwr_mgmt_exists(void) { return false; }
934 #endif /* CONFIG_ACPI */
935
936 static int __init intel_pstate_init(void)
937 {
938         int cpu, rc = 0;
939         const struct x86_cpu_id *id;
940         struct cpu_defaults *cpu_info;
941
942         if (no_load)
943                 return -ENODEV;
944
945         id = x86_match_cpu(intel_pstate_cpu_ids);
946         if (!id)
947                 return -ENODEV;
948
949         /*
950          * The Intel pstate driver will be ignored if the platform
951          * firmware has its own power management modes.
952          */
953         if (intel_pstate_platform_pwr_mgmt_exists())
954                 return -ENODEV;
955
956         cpu_info = (struct cpu_defaults *)id->driver_data;
957
958         copy_pid_params(&cpu_info->pid_policy);
959         copy_cpu_funcs(&cpu_info->funcs);
960
961         if (intel_pstate_msrs_not_valid())
962                 return -ENODEV;
963
964         pr_info("Intel P-state driver initializing.\n");
965
966         all_cpu_data = vzalloc(sizeof(void *) * num_possible_cpus());
967         if (!all_cpu_data)
968                 return -ENOMEM;
969
970         rc = cpufreq_register_driver(&intel_pstate_driver);
971         if (rc)
972                 goto out;
973
974         intel_pstate_debug_expose_params();
975         intel_pstate_sysfs_expose_params();
976
977         return rc;
978 out:
979         get_online_cpus();
980         for_each_online_cpu(cpu) {
981                 if (all_cpu_data[cpu]) {
982                         del_timer_sync(&all_cpu_data[cpu]->timer);
983                         kfree(all_cpu_data[cpu]);
984                 }
985         }
986
987         put_online_cpus();
988         vfree(all_cpu_data);
989         return -ENODEV;
990 }
991 device_initcall(intel_pstate_init);
992
993 static int __init intel_pstate_setup(char *str)
994 {
995         if (!str)
996                 return -EINVAL;
997
998         if (!strcmp(str, "disable"))
999                 no_load = 1;
1000         return 0;
1001 }
1002 early_param("intel_pstate", intel_pstate_setup);
1003
1004 MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>");
1005 MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors");
1006 MODULE_LICENSE("GPL");