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 <linux/vmalloc.h>
30 #include <trace/events/power.h>
31 
32 #include <asm/div64.h>
33 #include <asm/msr.h>
34 #include <asm/cpu_device_id.h>
35 #include <asm/cpufeature.h>
36 
37 #define ATOM_RATIOS		0x66a
38 #define ATOM_VIDS		0x66b
39 #define ATOM_TURBO_RATIOS	0x66c
40 #define ATOM_TURBO_VIDS		0x66d
41 
42 #define FRAC_BITS 8
43 #define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
44 #define fp_toint(X) ((X) >> FRAC_BITS)
45 
46 static inline int32_t mul_fp(int32_t x, int32_t y)
47 {
48 	return ((int64_t)x * (int64_t)y) >> FRAC_BITS;
49 }
50 
51 static inline int32_t div_fp(s64 x, s64 y)
52 {
53 	return div64_s64((int64_t)x << FRAC_BITS, y);
54 }
55 
56 static inline int ceiling_fp(int32_t x)
57 {
58 	int mask, ret;
59 
60 	ret = fp_toint(x);
61 	mask = (1 << FRAC_BITS) - 1;
62 	if (x & mask)
63 		ret += 1;
64 	return ret;
65 }
66 
67 struct sample {
68 	int32_t core_pct_busy;
69 	int32_t busy_scaled;
70 	u64 aperf;
71 	u64 mperf;
72 	u64 tsc;
73 	int freq;
74 	u64 time;
75 };
76 
77 struct pstate_data {
78 	int	current_pstate;
79 	int	min_pstate;
80 	int	max_pstate;
81 	int	max_pstate_physical;
82 	int	scaling;
83 	int	turbo_pstate;
84 };
85 
86 struct vid_data {
87 	int min;
88 	int max;
89 	int turbo;
90 	int32_t ratio;
91 };
92 
93 struct _pid {
94 	int setpoint;
95 	int32_t integral;
96 	int32_t p_gain;
97 	int32_t i_gain;
98 	int32_t d_gain;
99 	int deadband;
100 	int32_t last_err;
101 };
102 
103 struct cpudata {
104 	int cpu;
105 
106 	struct update_util_data update_util;
107 
108 	struct pstate_data pstate;
109 	struct vid_data vid;
110 	struct _pid pid;
111 
112 	u64	last_sample_time;
113 	u64	prev_aperf;
114 	u64	prev_mperf;
115 	u64	prev_tsc;
116 	u64	prev_cummulative_iowait;
117 	struct sample sample;
118 };
119 
120 static struct cpudata **all_cpu_data;
121 struct pstate_adjust_policy {
122 	int sample_rate_ms;
123 	s64 sample_rate_ns;
124 	int deadband;
125 	int setpoint;
126 	int p_gain_pct;
127 	int d_gain_pct;
128 	int i_gain_pct;
129 };
130 
131 struct pstate_funcs {
132 	int (*get_max)(void);
133 	int (*get_max_physical)(void);
134 	int (*get_min)(void);
135 	int (*get_turbo)(void);
136 	int (*get_scaling)(void);
137 	void (*set)(struct cpudata*, int pstate);
138 	void (*get_vid)(struct cpudata *);
139 	int32_t (*get_target_pstate)(struct cpudata *);
140 };
141 
142 struct cpu_defaults {
143 	struct pstate_adjust_policy pid_policy;
144 	struct pstate_funcs funcs;
145 };
146 
147 static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu);
148 static inline int32_t get_target_pstate_use_cpu_load(struct cpudata *cpu);
149 
150 static struct pstate_adjust_policy pid_params;
151 static struct pstate_funcs pstate_funcs;
152 static int hwp_active;
153 
154 struct perf_limits {
155 	int no_turbo;
156 	int turbo_disabled;
157 	int max_perf_pct;
158 	int min_perf_pct;
159 	int32_t max_perf;
160 	int32_t min_perf;
161 	int max_policy_pct;
162 	int max_sysfs_pct;
163 	int min_policy_pct;
164 	int min_sysfs_pct;
165 };
166 
167 static struct perf_limits performance_limits = {
168 	.no_turbo = 0,
169 	.turbo_disabled = 0,
170 	.max_perf_pct = 100,
171 	.max_perf = int_tofp(1),
172 	.min_perf_pct = 100,
173 	.min_perf = int_tofp(1),
174 	.max_policy_pct = 100,
175 	.max_sysfs_pct = 100,
176 	.min_policy_pct = 0,
177 	.min_sysfs_pct = 0,
178 };
179 
180 static struct perf_limits powersave_limits = {
181 	.no_turbo = 0,
182 	.turbo_disabled = 0,
183 	.max_perf_pct = 100,
184 	.max_perf = int_tofp(1),
185 	.min_perf_pct = 0,
186 	.min_perf = 0,
187 	.max_policy_pct = 100,
188 	.max_sysfs_pct = 100,
189 	.min_policy_pct = 0,
190 	.min_sysfs_pct = 0,
191 };
192 
193 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
194 static struct perf_limits *limits = &performance_limits;
195 #else
196 static struct perf_limits *limits = &powersave_limits;
197 #endif
198 
199 static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
200 			     int deadband, int integral) {
201 	pid->setpoint = setpoint;
202 	pid->deadband  = deadband;
203 	pid->integral  = int_tofp(integral);
204 	pid->last_err  = int_tofp(setpoint) - int_tofp(busy);
205 }
206 
207 static inline void pid_p_gain_set(struct _pid *pid, int percent)
208 {
209 	pid->p_gain = div_fp(int_tofp(percent), int_tofp(100));
210 }
211 
212 static inline void pid_i_gain_set(struct _pid *pid, int percent)
213 {
214 	pid->i_gain = div_fp(int_tofp(percent), int_tofp(100));
215 }
216 
217 static inline void pid_d_gain_set(struct _pid *pid, int percent)
218 {
219 	pid->d_gain = div_fp(int_tofp(percent), int_tofp(100));
220 }
221 
222 static signed int pid_calc(struct _pid *pid, int32_t busy)
223 {
224 	signed int result;
225 	int32_t pterm, dterm, fp_error;
226 	int32_t integral_limit;
227 
228 	fp_error = int_tofp(pid->setpoint) - busy;
229 
230 	if (abs(fp_error) <= int_tofp(pid->deadband))
231 		return 0;
232 
233 	pterm = mul_fp(pid->p_gain, fp_error);
234 
235 	pid->integral += fp_error;
236 
237 	/*
238 	 * We limit the integral here so that it will never
239 	 * get higher than 30.  This prevents it from becoming
240 	 * too large an input over long periods of time and allows
241 	 * it to get factored out sooner.
242 	 *
243 	 * The value of 30 was chosen through experimentation.
244 	 */
245 	integral_limit = int_tofp(30);
246 	if (pid->integral > integral_limit)
247 		pid->integral = integral_limit;
248 	if (pid->integral < -integral_limit)
249 		pid->integral = -integral_limit;
250 
251 	dterm = mul_fp(pid->d_gain, fp_error - pid->last_err);
252 	pid->last_err = fp_error;
253 
254 	result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm;
255 	result = result + (1 << (FRAC_BITS-1));
256 	return (signed int)fp_toint(result);
257 }
258 
259 static inline void intel_pstate_busy_pid_reset(struct cpudata *cpu)
260 {
261 	pid_p_gain_set(&cpu->pid, pid_params.p_gain_pct);
262 	pid_d_gain_set(&cpu->pid, pid_params.d_gain_pct);
263 	pid_i_gain_set(&cpu->pid, pid_params.i_gain_pct);
264 
265 	pid_reset(&cpu->pid, pid_params.setpoint, 100, pid_params.deadband, 0);
266 }
267 
268 static inline void intel_pstate_reset_all_pid(void)
269 {
270 	unsigned int cpu;
271 
272 	for_each_online_cpu(cpu) {
273 		if (all_cpu_data[cpu])
274 			intel_pstate_busy_pid_reset(all_cpu_data[cpu]);
275 	}
276 }
277 
278 static inline void update_turbo_state(void)
279 {
280 	u64 misc_en;
281 	struct cpudata *cpu;
282 
283 	cpu = all_cpu_data[0];
284 	rdmsrl(MSR_IA32_MISC_ENABLE, misc_en);
285 	limits->turbo_disabled =
286 		(misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE ||
287 		 cpu->pstate.max_pstate == cpu->pstate.turbo_pstate);
288 }
289 
290 static void intel_pstate_hwp_set(void)
291 {
292 	int min, hw_min, max, hw_max, cpu, range, adj_range;
293 	u64 value, cap;
294 
295 	rdmsrl(MSR_HWP_CAPABILITIES, cap);
296 	hw_min = HWP_LOWEST_PERF(cap);
297 	hw_max = HWP_HIGHEST_PERF(cap);
298 	range = hw_max - hw_min;
299 
300 	get_online_cpus();
301 
302 	for_each_online_cpu(cpu) {
303 		rdmsrl_on_cpu(cpu, MSR_HWP_REQUEST, &value);
304 		adj_range = limits->min_perf_pct * range / 100;
305 		min = hw_min + adj_range;
306 		value &= ~HWP_MIN_PERF(~0L);
307 		value |= HWP_MIN_PERF(min);
308 
309 		adj_range = limits->max_perf_pct * range / 100;
310 		max = hw_min + adj_range;
311 		if (limits->no_turbo) {
312 			hw_max = HWP_GUARANTEED_PERF(cap);
313 			if (hw_max < max)
314 				max = hw_max;
315 		}
316 
317 		value &= ~HWP_MAX_PERF(~0L);
318 		value |= HWP_MAX_PERF(max);
319 		wrmsrl_on_cpu(cpu, MSR_HWP_REQUEST, value);
320 	}
321 
322 	put_online_cpus();
323 }
324 
325 /************************** debugfs begin ************************/
326 static int pid_param_set(void *data, u64 val)
327 {
328 	*(u32 *)data = val;
329 	intel_pstate_reset_all_pid();
330 	return 0;
331 }
332 
333 static int pid_param_get(void *data, u64 *val)
334 {
335 	*val = *(u32 *)data;
336 	return 0;
337 }
338 DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get, pid_param_set, "%llu\n");
339 
340 struct pid_param {
341 	char *name;
342 	void *value;
343 };
344 
345 static struct pid_param pid_files[] = {
346 	{"sample_rate_ms", &pid_params.sample_rate_ms},
347 	{"d_gain_pct", &pid_params.d_gain_pct},
348 	{"i_gain_pct", &pid_params.i_gain_pct},
349 	{"deadband", &pid_params.deadband},
350 	{"setpoint", &pid_params.setpoint},
351 	{"p_gain_pct", &pid_params.p_gain_pct},
352 	{NULL, NULL}
353 };
354 
355 static void __init intel_pstate_debug_expose_params(void)
356 {
357 	struct dentry *debugfs_parent;
358 	int i = 0;
359 
360 	if (hwp_active)
361 		return;
362 	debugfs_parent = debugfs_create_dir("pstate_snb", NULL);
363 	if (IS_ERR_OR_NULL(debugfs_parent))
364 		return;
365 	while (pid_files[i].name) {
366 		debugfs_create_file(pid_files[i].name, 0660,
367 				    debugfs_parent, pid_files[i].value,
368 				    &fops_pid_param);
369 		i++;
370 	}
371 }
372 
373 /************************** debugfs end ************************/
374 
375 /************************** sysfs begin ************************/
376 #define show_one(file_name, object)					\
377 	static ssize_t show_##file_name					\
378 	(struct kobject *kobj, struct attribute *attr, char *buf)	\
379 	{								\
380 		return sprintf(buf, "%u\n", limits->object);		\
381 	}
382 
383 static ssize_t show_turbo_pct(struct kobject *kobj,
384 				struct attribute *attr, char *buf)
385 {
386 	struct cpudata *cpu;
387 	int total, no_turbo, turbo_pct;
388 	uint32_t turbo_fp;
389 
390 	cpu = all_cpu_data[0];
391 
392 	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
393 	no_turbo = cpu->pstate.max_pstate - cpu->pstate.min_pstate + 1;
394 	turbo_fp = div_fp(int_tofp(no_turbo), int_tofp(total));
395 	turbo_pct = 100 - fp_toint(mul_fp(turbo_fp, int_tofp(100)));
396 	return sprintf(buf, "%u\n", turbo_pct);
397 }
398 
399 static ssize_t show_num_pstates(struct kobject *kobj,
400 				struct attribute *attr, char *buf)
401 {
402 	struct cpudata *cpu;
403 	int total;
404 
405 	cpu = all_cpu_data[0];
406 	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
407 	return sprintf(buf, "%u\n", total);
408 }
409 
410 static ssize_t show_no_turbo(struct kobject *kobj,
411 			     struct attribute *attr, char *buf)
412 {
413 	ssize_t ret;
414 
415 	update_turbo_state();
416 	if (limits->turbo_disabled)
417 		ret = sprintf(buf, "%u\n", limits->turbo_disabled);
418 	else
419 		ret = sprintf(buf, "%u\n", limits->no_turbo);
420 
421 	return ret;
422 }
423 
424 static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
425 			      const char *buf, size_t count)
426 {
427 	unsigned int input;
428 	int ret;
429 
430 	ret = sscanf(buf, "%u", &input);
431 	if (ret != 1)
432 		return -EINVAL;
433 
434 	update_turbo_state();
435 	if (limits->turbo_disabled) {
436 		pr_warn("intel_pstate: Turbo disabled by BIOS or unavailable on processor\n");
437 		return -EPERM;
438 	}
439 
440 	limits->no_turbo = clamp_t(int, input, 0, 1);
441 
442 	if (hwp_active)
443 		intel_pstate_hwp_set();
444 
445 	return count;
446 }
447 
448 static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
449 				  const char *buf, size_t count)
450 {
451 	unsigned int input;
452 	int ret;
453 
454 	ret = sscanf(buf, "%u", &input);
455 	if (ret != 1)
456 		return -EINVAL;
457 
458 	limits->max_sysfs_pct = clamp_t(int, input, 0 , 100);
459 	limits->max_perf_pct = min(limits->max_policy_pct,
460 				   limits->max_sysfs_pct);
461 	limits->max_perf_pct = max(limits->min_policy_pct,
462 				   limits->max_perf_pct);
463 	limits->max_perf_pct = max(limits->min_perf_pct,
464 				   limits->max_perf_pct);
465 	limits->max_perf = div_fp(int_tofp(limits->max_perf_pct),
466 				  int_tofp(100));
467 
468 	if (hwp_active)
469 		intel_pstate_hwp_set();
470 	return count;
471 }
472 
473 static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
474 				  const char *buf, size_t count)
475 {
476 	unsigned int input;
477 	int ret;
478 
479 	ret = sscanf(buf, "%u", &input);
480 	if (ret != 1)
481 		return -EINVAL;
482 
483 	limits->min_sysfs_pct = clamp_t(int, input, 0 , 100);
484 	limits->min_perf_pct = max(limits->min_policy_pct,
485 				   limits->min_sysfs_pct);
486 	limits->min_perf_pct = min(limits->max_policy_pct,
487 				   limits->min_perf_pct);
488 	limits->min_perf_pct = min(limits->max_perf_pct,
489 				   limits->min_perf_pct);
490 	limits->min_perf = div_fp(int_tofp(limits->min_perf_pct),
491 				  int_tofp(100));
492 
493 	if (hwp_active)
494 		intel_pstate_hwp_set();
495 	return count;
496 }
497 
498 show_one(max_perf_pct, max_perf_pct);
499 show_one(min_perf_pct, min_perf_pct);
500 
501 define_one_global_rw(no_turbo);
502 define_one_global_rw(max_perf_pct);
503 define_one_global_rw(min_perf_pct);
504 define_one_global_ro(turbo_pct);
505 define_one_global_ro(num_pstates);
506 
507 static struct attribute *intel_pstate_attributes[] = {
508 	&no_turbo.attr,
509 	&max_perf_pct.attr,
510 	&min_perf_pct.attr,
511 	&turbo_pct.attr,
512 	&num_pstates.attr,
513 	NULL
514 };
515 
516 static struct attribute_group intel_pstate_attr_group = {
517 	.attrs = intel_pstate_attributes,
518 };
519 
520 static void __init intel_pstate_sysfs_expose_params(void)
521 {
522 	struct kobject *intel_pstate_kobject;
523 	int rc;
524 
525 	intel_pstate_kobject = kobject_create_and_add("intel_pstate",
526 						&cpu_subsys.dev_root->kobj);
527 	BUG_ON(!intel_pstate_kobject);
528 	rc = sysfs_create_group(intel_pstate_kobject, &intel_pstate_attr_group);
529 	BUG_ON(rc);
530 }
531 /************************** sysfs end ************************/
532 
533 static void intel_pstate_hwp_enable(struct cpudata *cpudata)
534 {
535 	wrmsrl_on_cpu(cpudata->cpu, MSR_PM_ENABLE, 0x1);
536 }
537 
538 static int atom_get_min_pstate(void)
539 {
540 	u64 value;
541 
542 	rdmsrl(ATOM_RATIOS, value);
543 	return (value >> 8) & 0x7F;
544 }
545 
546 static int atom_get_max_pstate(void)
547 {
548 	u64 value;
549 
550 	rdmsrl(ATOM_RATIOS, value);
551 	return (value >> 16) & 0x7F;
552 }
553 
554 static int atom_get_turbo_pstate(void)
555 {
556 	u64 value;
557 
558 	rdmsrl(ATOM_TURBO_RATIOS, value);
559 	return value & 0x7F;
560 }
561 
562 static void atom_set_pstate(struct cpudata *cpudata, int pstate)
563 {
564 	u64 val;
565 	int32_t vid_fp;
566 	u32 vid;
567 
568 	val = (u64)pstate << 8;
569 	if (limits->no_turbo && !limits->turbo_disabled)
570 		val |= (u64)1 << 32;
571 
572 	vid_fp = cpudata->vid.min + mul_fp(
573 		int_tofp(pstate - cpudata->pstate.min_pstate),
574 		cpudata->vid.ratio);
575 
576 	vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
577 	vid = ceiling_fp(vid_fp);
578 
579 	if (pstate > cpudata->pstate.max_pstate)
580 		vid = cpudata->vid.turbo;
581 
582 	val |= vid;
583 
584 	wrmsrl_on_cpu(cpudata->cpu, MSR_IA32_PERF_CTL, val);
585 }
586 
587 static int silvermont_get_scaling(void)
588 {
589 	u64 value;
590 	int i;
591 	/* Defined in Table 35-6 from SDM (Sept 2015) */
592 	static int silvermont_freq_table[] = {
593 		83300, 100000, 133300, 116700, 80000};
594 
595 	rdmsrl(MSR_FSB_FREQ, value);
596 	i = value & 0x7;
597 	WARN_ON(i > 4);
598 
599 	return silvermont_freq_table[i];
600 }
601 
602 static int airmont_get_scaling(void)
603 {
604 	u64 value;
605 	int i;
606 	/* Defined in Table 35-10 from SDM (Sept 2015) */
607 	static int airmont_freq_table[] = {
608 		83300, 100000, 133300, 116700, 80000,
609 		93300, 90000, 88900, 87500};
610 
611 	rdmsrl(MSR_FSB_FREQ, value);
612 	i = value & 0xF;
613 	WARN_ON(i > 8);
614 
615 	return airmont_freq_table[i];
616 }
617 
618 static void atom_get_vid(struct cpudata *cpudata)
619 {
620 	u64 value;
621 
622 	rdmsrl(ATOM_VIDS, value);
623 	cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
624 	cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
625 	cpudata->vid.ratio = div_fp(
626 		cpudata->vid.max - cpudata->vid.min,
627 		int_tofp(cpudata->pstate.max_pstate -
628 			cpudata->pstate.min_pstate));
629 
630 	rdmsrl(ATOM_TURBO_VIDS, value);
631 	cpudata->vid.turbo = value & 0x7f;
632 }
633 
634 static int core_get_min_pstate(void)
635 {
636 	u64 value;
637 
638 	rdmsrl(MSR_PLATFORM_INFO, value);
639 	return (value >> 40) & 0xFF;
640 }
641 
642 static int core_get_max_pstate_physical(void)
643 {
644 	u64 value;
645 
646 	rdmsrl(MSR_PLATFORM_INFO, value);
647 	return (value >> 8) & 0xFF;
648 }
649 
650 static int core_get_max_pstate(void)
651 {
652 	u64 tar;
653 	u64 plat_info;
654 	int max_pstate;
655 	int err;
656 
657 	rdmsrl(MSR_PLATFORM_INFO, plat_info);
658 	max_pstate = (plat_info >> 8) & 0xFF;
659 
660 	err = rdmsrl_safe(MSR_TURBO_ACTIVATION_RATIO, &tar);
661 	if (!err) {
662 		/* Do some sanity checking for safety */
663 		if (plat_info & 0x600000000) {
664 			u64 tdp_ctrl;
665 			u64 tdp_ratio;
666 			int tdp_msr;
667 
668 			err = rdmsrl_safe(MSR_CONFIG_TDP_CONTROL, &tdp_ctrl);
669 			if (err)
670 				goto skip_tar;
671 
672 			tdp_msr = MSR_CONFIG_TDP_NOMINAL + tdp_ctrl;
673 			err = rdmsrl_safe(tdp_msr, &tdp_ratio);
674 			if (err)
675 				goto skip_tar;
676 
677 			if (tdp_ratio - 1 == tar) {
678 				max_pstate = tar;
679 				pr_debug("max_pstate=TAC %x\n", max_pstate);
680 			} else {
681 				goto skip_tar;
682 			}
683 		}
684 	}
685 
686 skip_tar:
687 	return max_pstate;
688 }
689 
690 static int core_get_turbo_pstate(void)
691 {
692 	u64 value;
693 	int nont, ret;
694 
695 	rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value);
696 	nont = core_get_max_pstate();
697 	ret = (value) & 255;
698 	if (ret <= nont)
699 		ret = nont;
700 	return ret;
701 }
702 
703 static inline int core_get_scaling(void)
704 {
705 	return 100000;
706 }
707 
708 static void core_set_pstate(struct cpudata *cpudata, int pstate)
709 {
710 	u64 val;
711 
712 	val = (u64)pstate << 8;
713 	if (limits->no_turbo && !limits->turbo_disabled)
714 		val |= (u64)1 << 32;
715 
716 	wrmsrl(MSR_IA32_PERF_CTL, val);
717 }
718 
719 static int knl_get_turbo_pstate(void)
720 {
721 	u64 value;
722 	int nont, ret;
723 
724 	rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value);
725 	nont = core_get_max_pstate();
726 	ret = (((value) >> 8) & 0xFF);
727 	if (ret <= nont)
728 		ret = nont;
729 	return ret;
730 }
731 
732 static struct cpu_defaults core_params = {
733 	.pid_policy = {
734 		.sample_rate_ms = 10,
735 		.deadband = 0,
736 		.setpoint = 97,
737 		.p_gain_pct = 20,
738 		.d_gain_pct = 0,
739 		.i_gain_pct = 0,
740 	},
741 	.funcs = {
742 		.get_max = core_get_max_pstate,
743 		.get_max_physical = core_get_max_pstate_physical,
744 		.get_min = core_get_min_pstate,
745 		.get_turbo = core_get_turbo_pstate,
746 		.get_scaling = core_get_scaling,
747 		.set = core_set_pstate,
748 		.get_target_pstate = get_target_pstate_use_performance,
749 	},
750 };
751 
752 static struct cpu_defaults silvermont_params = {
753 	.pid_policy = {
754 		.sample_rate_ms = 10,
755 		.deadband = 0,
756 		.setpoint = 60,
757 		.p_gain_pct = 14,
758 		.d_gain_pct = 0,
759 		.i_gain_pct = 4,
760 	},
761 	.funcs = {
762 		.get_max = atom_get_max_pstate,
763 		.get_max_physical = atom_get_max_pstate,
764 		.get_min = atom_get_min_pstate,
765 		.get_turbo = atom_get_turbo_pstate,
766 		.set = atom_set_pstate,
767 		.get_scaling = silvermont_get_scaling,
768 		.get_vid = atom_get_vid,
769 		.get_target_pstate = get_target_pstate_use_cpu_load,
770 	},
771 };
772 
773 static struct cpu_defaults airmont_params = {
774 	.pid_policy = {
775 		.sample_rate_ms = 10,
776 		.deadband = 0,
777 		.setpoint = 60,
778 		.p_gain_pct = 14,
779 		.d_gain_pct = 0,
780 		.i_gain_pct = 4,
781 	},
782 	.funcs = {
783 		.get_max = atom_get_max_pstate,
784 		.get_max_physical = atom_get_max_pstate,
785 		.get_min = atom_get_min_pstate,
786 		.get_turbo = atom_get_turbo_pstate,
787 		.set = atom_set_pstate,
788 		.get_scaling = airmont_get_scaling,
789 		.get_vid = atom_get_vid,
790 		.get_target_pstate = get_target_pstate_use_cpu_load,
791 	},
792 };
793 
794 static struct cpu_defaults knl_params = {
795 	.pid_policy = {
796 		.sample_rate_ms = 10,
797 		.deadband = 0,
798 		.setpoint = 97,
799 		.p_gain_pct = 20,
800 		.d_gain_pct = 0,
801 		.i_gain_pct = 0,
802 	},
803 	.funcs = {
804 		.get_max = core_get_max_pstate,
805 		.get_max_physical = core_get_max_pstate_physical,
806 		.get_min = core_get_min_pstate,
807 		.get_turbo = knl_get_turbo_pstate,
808 		.get_scaling = core_get_scaling,
809 		.set = core_set_pstate,
810 		.get_target_pstate = get_target_pstate_use_performance,
811 	},
812 };
813 
814 static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max)
815 {
816 	int max_perf = cpu->pstate.turbo_pstate;
817 	int max_perf_adj;
818 	int min_perf;
819 
820 	if (limits->no_turbo || limits->turbo_disabled)
821 		max_perf = cpu->pstate.max_pstate;
822 
823 	/*
824 	 * performance can be limited by user through sysfs, by cpufreq
825 	 * policy, or by cpu specific default values determined through
826 	 * experimentation.
827 	 */
828 	max_perf_adj = fp_toint(mul_fp(int_tofp(max_perf), limits->max_perf));
829 	*max = clamp_t(int, max_perf_adj,
830 			cpu->pstate.min_pstate, cpu->pstate.turbo_pstate);
831 
832 	min_perf = fp_toint(mul_fp(int_tofp(max_perf), limits->min_perf));
833 	*min = clamp_t(int, min_perf, cpu->pstate.min_pstate, max_perf);
834 }
835 
836 static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate, bool force)
837 {
838 	int max_perf, min_perf;
839 
840 	if (force) {
841 		update_turbo_state();
842 
843 		intel_pstate_get_min_max(cpu, &min_perf, &max_perf);
844 
845 		pstate = clamp_t(int, pstate, min_perf, max_perf);
846 
847 		if (pstate == cpu->pstate.current_pstate)
848 			return;
849 	}
850 	trace_cpu_frequency(pstate * cpu->pstate.scaling, cpu->cpu);
851 
852 	cpu->pstate.current_pstate = pstate;
853 
854 	pstate_funcs.set(cpu, pstate);
855 }
856 
857 static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
858 {
859 	cpu->pstate.min_pstate = pstate_funcs.get_min();
860 	cpu->pstate.max_pstate = pstate_funcs.get_max();
861 	cpu->pstate.max_pstate_physical = pstate_funcs.get_max_physical();
862 	cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
863 	cpu->pstate.scaling = pstate_funcs.get_scaling();
864 
865 	if (pstate_funcs.get_vid)
866 		pstate_funcs.get_vid(cpu);
867 	intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate, false);
868 }
869 
870 static inline void intel_pstate_calc_busy(struct cpudata *cpu)
871 {
872 	struct sample *sample = &cpu->sample;
873 	int64_t core_pct;
874 
875 	core_pct = int_tofp(sample->aperf) * int_tofp(100);
876 	core_pct = div64_u64(core_pct, int_tofp(sample->mperf));
877 
878 	sample->freq = fp_toint(
879 		mul_fp(int_tofp(
880 			cpu->pstate.max_pstate_physical *
881 			cpu->pstate.scaling / 100),
882 			core_pct));
883 
884 	sample->core_pct_busy = (int32_t)core_pct;
885 }
886 
887 static inline void intel_pstate_sample(struct cpudata *cpu, u64 time)
888 {
889 	u64 aperf, mperf;
890 	unsigned long flags;
891 	u64 tsc;
892 
893 	local_irq_save(flags);
894 	rdmsrl(MSR_IA32_APERF, aperf);
895 	rdmsrl(MSR_IA32_MPERF, mperf);
896 	tsc = rdtsc();
897 	if ((cpu->prev_mperf == mperf) || (cpu->prev_tsc == tsc)) {
898 		local_irq_restore(flags);
899 		return;
900 	}
901 	local_irq_restore(flags);
902 
903 	cpu->last_sample_time = cpu->sample.time;
904 	cpu->sample.time = time;
905 	cpu->sample.aperf = aperf;
906 	cpu->sample.mperf = mperf;
907 	cpu->sample.tsc =  tsc;
908 	cpu->sample.aperf -= cpu->prev_aperf;
909 	cpu->sample.mperf -= cpu->prev_mperf;
910 	cpu->sample.tsc -= cpu->prev_tsc;
911 
912 	intel_pstate_calc_busy(cpu);
913 
914 	cpu->prev_aperf = aperf;
915 	cpu->prev_mperf = mperf;
916 	cpu->prev_tsc = tsc;
917 }
918 
919 static inline int32_t get_target_pstate_use_cpu_load(struct cpudata *cpu)
920 {
921 	struct sample *sample = &cpu->sample;
922 	u64 cummulative_iowait, delta_iowait_us;
923 	u64 delta_iowait_mperf;
924 	u64 mperf, now;
925 	int32_t cpu_load;
926 
927 	cummulative_iowait = get_cpu_iowait_time_us(cpu->cpu, &now);
928 
929 	/*
930 	 * Convert iowait time into number of IO cycles spent at max_freq.
931 	 * IO is considered as busy only for the cpu_load algorithm. For
932 	 * performance this is not needed since we always try to reach the
933 	 * maximum P-State, so we are already boosting the IOs.
934 	 */
935 	delta_iowait_us = cummulative_iowait - cpu->prev_cummulative_iowait;
936 	delta_iowait_mperf = div64_u64(delta_iowait_us * cpu->pstate.scaling *
937 		cpu->pstate.max_pstate, MSEC_PER_SEC);
938 
939 	mperf = cpu->sample.mperf + delta_iowait_mperf;
940 	cpu->prev_cummulative_iowait = cummulative_iowait;
941 
942 
943 	/*
944 	 * The load can be estimated as the ratio of the mperf counter
945 	 * running at a constant frequency during active periods
946 	 * (C0) and the time stamp counter running at the same frequency
947 	 * also during C-states.
948 	 */
949 	cpu_load = div64_u64(int_tofp(100) * mperf, sample->tsc);
950 	cpu->sample.busy_scaled = cpu_load;
951 
952 	return cpu->pstate.current_pstate - pid_calc(&cpu->pid, cpu_load);
953 }
954 
955 static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu)
956 {
957 	int32_t core_busy, max_pstate, current_pstate, sample_ratio;
958 	u64 duration_ns;
959 
960 	/*
961 	 * core_busy is the ratio of actual performance to max
962 	 * max_pstate is the max non turbo pstate available
963 	 * current_pstate was the pstate that was requested during
964 	 * 	the last sample period.
965 	 *
966 	 * We normalize core_busy, which was our actual percent
967 	 * performance to what we requested during the last sample
968 	 * period. The result will be a percentage of busy at a
969 	 * specified pstate.
970 	 */
971 	core_busy = cpu->sample.core_pct_busy;
972 	max_pstate = int_tofp(cpu->pstate.max_pstate_physical);
973 	current_pstate = int_tofp(cpu->pstate.current_pstate);
974 	core_busy = mul_fp(core_busy, div_fp(max_pstate, current_pstate));
975 
976 	/*
977 	 * Since our utilization update callback will not run unless we are
978 	 * in C0, check if the actual elapsed time is significantly greater (3x)
979 	 * than our sample interval.  If it is, then we were idle for a long
980 	 * enough period of time to adjust our busyness.
981 	 */
982 	duration_ns = cpu->sample.time - cpu->last_sample_time;
983 	if ((s64)duration_ns > pid_params.sample_rate_ns * 3
984 	    && cpu->last_sample_time > 0) {
985 		sample_ratio = div_fp(int_tofp(pid_params.sample_rate_ns),
986 				      int_tofp(duration_ns));
987 		core_busy = mul_fp(core_busy, sample_ratio);
988 	}
989 
990 	cpu->sample.busy_scaled = core_busy;
991 	return cpu->pstate.current_pstate - pid_calc(&cpu->pid, core_busy);
992 }
993 
994 static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
995 {
996 	int from, target_pstate;
997 	struct sample *sample;
998 
999 	from = cpu->pstate.current_pstate;
1000 
1001 	target_pstate = pstate_funcs.get_target_pstate(cpu);
1002 
1003 	intel_pstate_set_pstate(cpu, target_pstate, true);
1004 
1005 	sample = &cpu->sample;
1006 	trace_pstate_sample(fp_toint(sample->core_pct_busy),
1007 		fp_toint(sample->busy_scaled),
1008 		from,
1009 		cpu->pstate.current_pstate,
1010 		sample->mperf,
1011 		sample->aperf,
1012 		sample->tsc,
1013 		sample->freq);
1014 }
1015 
1016 static void intel_pstate_update_util(struct update_util_data *data, u64 time,
1017 				     unsigned long util, unsigned long max)
1018 {
1019 	struct cpudata *cpu = container_of(data, struct cpudata, update_util);
1020 	u64 delta_ns = time - cpu->sample.time;
1021 
1022 	if ((s64)delta_ns >= pid_params.sample_rate_ns) {
1023 		intel_pstate_sample(cpu, time);
1024 		if (!hwp_active)
1025 			intel_pstate_adjust_busy_pstate(cpu);
1026 	}
1027 }
1028 
1029 #define ICPU(model, policy) \
1030 	{ X86_VENDOR_INTEL, 6, model, X86_FEATURE_APERFMPERF,\
1031 			(unsigned long)&policy }
1032 
1033 static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
1034 	ICPU(0x2a, core_params),
1035 	ICPU(0x2d, core_params),
1036 	ICPU(0x37, silvermont_params),
1037 	ICPU(0x3a, core_params),
1038 	ICPU(0x3c, core_params),
1039 	ICPU(0x3d, core_params),
1040 	ICPU(0x3e, core_params),
1041 	ICPU(0x3f, core_params),
1042 	ICPU(0x45, core_params),
1043 	ICPU(0x46, core_params),
1044 	ICPU(0x47, core_params),
1045 	ICPU(0x4c, airmont_params),
1046 	ICPU(0x4e, core_params),
1047 	ICPU(0x4f, core_params),
1048 	ICPU(0x5e, core_params),
1049 	ICPU(0x56, core_params),
1050 	ICPU(0x57, knl_params),
1051 	{}
1052 };
1053 MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
1054 
1055 static const struct x86_cpu_id intel_pstate_cpu_oob_ids[] = {
1056 	ICPU(0x56, core_params),
1057 	{}
1058 };
1059 
1060 static int intel_pstate_init_cpu(unsigned int cpunum)
1061 {
1062 	struct cpudata *cpu;
1063 
1064 	if (!all_cpu_data[cpunum])
1065 		all_cpu_data[cpunum] = kzalloc(sizeof(struct cpudata),
1066 					       GFP_KERNEL);
1067 	if (!all_cpu_data[cpunum])
1068 		return -ENOMEM;
1069 
1070 	cpu = all_cpu_data[cpunum];
1071 
1072 	cpu->cpu = cpunum;
1073 
1074 	if (hwp_active) {
1075 		intel_pstate_hwp_enable(cpu);
1076 		pid_params.sample_rate_ms = 50;
1077 		pid_params.sample_rate_ns = 50 * NSEC_PER_MSEC;
1078 	}
1079 
1080 	intel_pstate_get_cpu_pstates(cpu);
1081 
1082 	intel_pstate_busy_pid_reset(cpu);
1083 	intel_pstate_sample(cpu, 0);
1084 
1085 	cpu->update_util.func = intel_pstate_update_util;
1086 	cpufreq_set_update_util_data(cpunum, &cpu->update_util);
1087 
1088 	pr_debug("intel_pstate: controlling: cpu %d\n", cpunum);
1089 
1090 	return 0;
1091 }
1092 
1093 static unsigned int intel_pstate_get(unsigned int cpu_num)
1094 {
1095 	struct sample *sample;
1096 	struct cpudata *cpu;
1097 
1098 	cpu = all_cpu_data[cpu_num];
1099 	if (!cpu)
1100 		return 0;
1101 	sample = &cpu->sample;
1102 	return sample->freq;
1103 }
1104 
1105 static int intel_pstate_set_policy(struct cpufreq_policy *policy)
1106 {
1107 	if (!policy->cpuinfo.max_freq)
1108 		return -ENODEV;
1109 
1110 	if (policy->policy == CPUFREQ_POLICY_PERFORMANCE &&
1111 	    policy->max >= policy->cpuinfo.max_freq) {
1112 		pr_debug("intel_pstate: set performance\n");
1113 		limits = &performance_limits;
1114 		if (hwp_active)
1115 			intel_pstate_hwp_set();
1116 		return 0;
1117 	}
1118 
1119 	pr_debug("intel_pstate: set powersave\n");
1120 	limits = &powersave_limits;
1121 	limits->min_policy_pct = (policy->min * 100) / policy->cpuinfo.max_freq;
1122 	limits->min_policy_pct = clamp_t(int, limits->min_policy_pct, 0 , 100);
1123 	limits->max_policy_pct = DIV_ROUND_UP(policy->max * 100,
1124 					      policy->cpuinfo.max_freq);
1125 	limits->max_policy_pct = clamp_t(int, limits->max_policy_pct, 0 , 100);
1126 
1127 	/* Normalize user input to [min_policy_pct, max_policy_pct] */
1128 	limits->min_perf_pct = max(limits->min_policy_pct,
1129 				   limits->min_sysfs_pct);
1130 	limits->min_perf_pct = min(limits->max_policy_pct,
1131 				   limits->min_perf_pct);
1132 	limits->max_perf_pct = min(limits->max_policy_pct,
1133 				   limits->max_sysfs_pct);
1134 	limits->max_perf_pct = max(limits->min_policy_pct,
1135 				   limits->max_perf_pct);
1136 	limits->max_perf = round_up(limits->max_perf, FRAC_BITS);
1137 
1138 	/* Make sure min_perf_pct <= max_perf_pct */
1139 	limits->min_perf_pct = min(limits->max_perf_pct, limits->min_perf_pct);
1140 
1141 	limits->min_perf = div_fp(int_tofp(limits->min_perf_pct),
1142 				  int_tofp(100));
1143 	limits->max_perf = div_fp(int_tofp(limits->max_perf_pct),
1144 				  int_tofp(100));
1145 
1146 	if (hwp_active)
1147 		intel_pstate_hwp_set();
1148 
1149 	return 0;
1150 }
1151 
1152 static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
1153 {
1154 	cpufreq_verify_within_cpu_limits(policy);
1155 
1156 	if (policy->policy != CPUFREQ_POLICY_POWERSAVE &&
1157 	    policy->policy != CPUFREQ_POLICY_PERFORMANCE)
1158 		return -EINVAL;
1159 
1160 	return 0;
1161 }
1162 
1163 static void intel_pstate_stop_cpu(struct cpufreq_policy *policy)
1164 {
1165 	int cpu_num = policy->cpu;
1166 	struct cpudata *cpu = all_cpu_data[cpu_num];
1167 
1168 	pr_debug("intel_pstate: CPU %d exiting\n", cpu_num);
1169 
1170 	cpufreq_set_update_util_data(cpu_num, NULL);
1171 	synchronize_sched();
1172 
1173 	if (hwp_active)
1174 		return;
1175 
1176 	intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate, false);
1177 }
1178 
1179 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
1180 {
1181 	struct cpudata *cpu;
1182 	int rc;
1183 
1184 	rc = intel_pstate_init_cpu(policy->cpu);
1185 	if (rc)
1186 		return rc;
1187 
1188 	cpu = all_cpu_data[policy->cpu];
1189 
1190 	if (limits->min_perf_pct == 100 && limits->max_perf_pct == 100)
1191 		policy->policy = CPUFREQ_POLICY_PERFORMANCE;
1192 	else
1193 		policy->policy = CPUFREQ_POLICY_POWERSAVE;
1194 
1195 	policy->min = cpu->pstate.min_pstate * cpu->pstate.scaling;
1196 	policy->max = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
1197 
1198 	/* cpuinfo and default policy values */
1199 	policy->cpuinfo.min_freq = cpu->pstate.min_pstate * cpu->pstate.scaling;
1200 	policy->cpuinfo.max_freq =
1201 		cpu->pstate.turbo_pstate * cpu->pstate.scaling;
1202 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
1203 	cpumask_set_cpu(policy->cpu, policy->cpus);
1204 
1205 	return 0;
1206 }
1207 
1208 static struct cpufreq_driver intel_pstate_driver = {
1209 	.flags		= CPUFREQ_CONST_LOOPS,
1210 	.verify		= intel_pstate_verify_policy,
1211 	.setpolicy	= intel_pstate_set_policy,
1212 	.get		= intel_pstate_get,
1213 	.init		= intel_pstate_cpu_init,
1214 	.stop_cpu	= intel_pstate_stop_cpu,
1215 	.name		= "intel_pstate",
1216 };
1217 
1218 static int __initdata no_load;
1219 static int __initdata no_hwp;
1220 static int __initdata hwp_only;
1221 static unsigned int force_load;
1222 
1223 static int intel_pstate_msrs_not_valid(void)
1224 {
1225 	if (!pstate_funcs.get_max() ||
1226 	    !pstate_funcs.get_min() ||
1227 	    !pstate_funcs.get_turbo())
1228 		return -ENODEV;
1229 
1230 	return 0;
1231 }
1232 
1233 static void copy_pid_params(struct pstate_adjust_policy *policy)
1234 {
1235 	pid_params.sample_rate_ms = policy->sample_rate_ms;
1236 	pid_params.sample_rate_ns = pid_params.sample_rate_ms * NSEC_PER_MSEC;
1237 	pid_params.p_gain_pct = policy->p_gain_pct;
1238 	pid_params.i_gain_pct = policy->i_gain_pct;
1239 	pid_params.d_gain_pct = policy->d_gain_pct;
1240 	pid_params.deadband = policy->deadband;
1241 	pid_params.setpoint = policy->setpoint;
1242 }
1243 
1244 static void copy_cpu_funcs(struct pstate_funcs *funcs)
1245 {
1246 	pstate_funcs.get_max   = funcs->get_max;
1247 	pstate_funcs.get_max_physical = funcs->get_max_physical;
1248 	pstate_funcs.get_min   = funcs->get_min;
1249 	pstate_funcs.get_turbo = funcs->get_turbo;
1250 	pstate_funcs.get_scaling = funcs->get_scaling;
1251 	pstate_funcs.set       = funcs->set;
1252 	pstate_funcs.get_vid   = funcs->get_vid;
1253 	pstate_funcs.get_target_pstate = funcs->get_target_pstate;
1254 
1255 }
1256 
1257 #if IS_ENABLED(CONFIG_ACPI)
1258 #include <acpi/processor.h>
1259 
1260 static bool intel_pstate_no_acpi_pss(void)
1261 {
1262 	int i;
1263 
1264 	for_each_possible_cpu(i) {
1265 		acpi_status status;
1266 		union acpi_object *pss;
1267 		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1268 		struct acpi_processor *pr = per_cpu(processors, i);
1269 
1270 		if (!pr)
1271 			continue;
1272 
1273 		status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
1274 		if (ACPI_FAILURE(status))
1275 			continue;
1276 
1277 		pss = buffer.pointer;
1278 		if (pss && pss->type == ACPI_TYPE_PACKAGE) {
1279 			kfree(pss);
1280 			return false;
1281 		}
1282 
1283 		kfree(pss);
1284 	}
1285 
1286 	return true;
1287 }
1288 
1289 static bool intel_pstate_has_acpi_ppc(void)
1290 {
1291 	int i;
1292 
1293 	for_each_possible_cpu(i) {
1294 		struct acpi_processor *pr = per_cpu(processors, i);
1295 
1296 		if (!pr)
1297 			continue;
1298 		if (acpi_has_method(pr->handle, "_PPC"))
1299 			return true;
1300 	}
1301 	return false;
1302 }
1303 
1304 enum {
1305 	PSS,
1306 	PPC,
1307 };
1308 
1309 struct hw_vendor_info {
1310 	u16  valid;
1311 	char oem_id[ACPI_OEM_ID_SIZE];
1312 	char oem_table_id[ACPI_OEM_TABLE_ID_SIZE];
1313 	int  oem_pwr_table;
1314 };
1315 
1316 /* Hardware vendor-specific info that has its own power management modes */
1317 static struct hw_vendor_info vendor_info[] = {
1318 	{1, "HP    ", "ProLiant", PSS},
1319 	{1, "ORACLE", "X4-2    ", PPC},
1320 	{1, "ORACLE", "X4-2L   ", PPC},
1321 	{1, "ORACLE", "X4-2B   ", PPC},
1322 	{1, "ORACLE", "X3-2    ", PPC},
1323 	{1, "ORACLE", "X3-2L   ", PPC},
1324 	{1, "ORACLE", "X3-2B   ", PPC},
1325 	{1, "ORACLE", "X4470M2 ", PPC},
1326 	{1, "ORACLE", "X4270M3 ", PPC},
1327 	{1, "ORACLE", "X4270M2 ", PPC},
1328 	{1, "ORACLE", "X4170M2 ", PPC},
1329 	{1, "ORACLE", "X4170 M3", PPC},
1330 	{1, "ORACLE", "X4275 M3", PPC},
1331 	{1, "ORACLE", "X6-2    ", PPC},
1332 	{1, "ORACLE", "Sudbury ", PPC},
1333 	{0, "", ""},
1334 };
1335 
1336 static bool intel_pstate_platform_pwr_mgmt_exists(void)
1337 {
1338 	struct acpi_table_header hdr;
1339 	struct hw_vendor_info *v_info;
1340 	const struct x86_cpu_id *id;
1341 	u64 misc_pwr;
1342 
1343 	id = x86_match_cpu(intel_pstate_cpu_oob_ids);
1344 	if (id) {
1345 		rdmsrl(MSR_MISC_PWR_MGMT, misc_pwr);
1346 		if ( misc_pwr & (1 << 8))
1347 			return true;
1348 	}
1349 
1350 	if (acpi_disabled ||
1351 	    ACPI_FAILURE(acpi_get_table_header(ACPI_SIG_FADT, 0, &hdr)))
1352 		return false;
1353 
1354 	for (v_info = vendor_info; v_info->valid; v_info++) {
1355 		if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) &&
1356 			!strncmp(hdr.oem_table_id, v_info->oem_table_id,
1357 						ACPI_OEM_TABLE_ID_SIZE))
1358 			switch (v_info->oem_pwr_table) {
1359 			case PSS:
1360 				return intel_pstate_no_acpi_pss();
1361 			case PPC:
1362 				return intel_pstate_has_acpi_ppc() &&
1363 					(!force_load);
1364 			}
1365 	}
1366 
1367 	return false;
1368 }
1369 #else /* CONFIG_ACPI not enabled */
1370 static inline bool intel_pstate_platform_pwr_mgmt_exists(void) { return false; }
1371 static inline bool intel_pstate_has_acpi_ppc(void) { return false; }
1372 #endif /* CONFIG_ACPI */
1373 
1374 static int __init intel_pstate_init(void)
1375 {
1376 	int cpu, rc = 0;
1377 	const struct x86_cpu_id *id;
1378 	struct cpu_defaults *cpu_def;
1379 
1380 	if (no_load)
1381 		return -ENODEV;
1382 
1383 	id = x86_match_cpu(intel_pstate_cpu_ids);
1384 	if (!id)
1385 		return -ENODEV;
1386 
1387 	/*
1388 	 * The Intel pstate driver will be ignored if the platform
1389 	 * firmware has its own power management modes.
1390 	 */
1391 	if (intel_pstate_platform_pwr_mgmt_exists())
1392 		return -ENODEV;
1393 
1394 	cpu_def = (struct cpu_defaults *)id->driver_data;
1395 
1396 	copy_pid_params(&cpu_def->pid_policy);
1397 	copy_cpu_funcs(&cpu_def->funcs);
1398 
1399 	if (intel_pstate_msrs_not_valid())
1400 		return -ENODEV;
1401 
1402 	pr_info("Intel P-state driver initializing.\n");
1403 
1404 	all_cpu_data = vzalloc(sizeof(void *) * num_possible_cpus());
1405 	if (!all_cpu_data)
1406 		return -ENOMEM;
1407 
1408 	if (static_cpu_has_safe(X86_FEATURE_HWP) && !no_hwp) {
1409 		pr_info("intel_pstate: HWP enabled\n");
1410 		hwp_active++;
1411 	}
1412 
1413 	if (!hwp_active && hwp_only)
1414 		goto out;
1415 
1416 	rc = cpufreq_register_driver(&intel_pstate_driver);
1417 	if (rc)
1418 		goto out;
1419 
1420 	intel_pstate_debug_expose_params();
1421 	intel_pstate_sysfs_expose_params();
1422 
1423 	return rc;
1424 out:
1425 	get_online_cpus();
1426 	for_each_online_cpu(cpu) {
1427 		if (all_cpu_data[cpu]) {
1428 			cpufreq_set_update_util_data(cpu, NULL);
1429 			synchronize_sched();
1430 			kfree(all_cpu_data[cpu]);
1431 		}
1432 	}
1433 
1434 	put_online_cpus();
1435 	vfree(all_cpu_data);
1436 	return -ENODEV;
1437 }
1438 device_initcall(intel_pstate_init);
1439 
1440 static int __init intel_pstate_setup(char *str)
1441 {
1442 	if (!str)
1443 		return -EINVAL;
1444 
1445 	if (!strcmp(str, "disable"))
1446 		no_load = 1;
1447 	if (!strcmp(str, "no_hwp")) {
1448 		pr_info("intel_pstate: HWP disabled\n");
1449 		no_hwp = 1;
1450 	}
1451 	if (!strcmp(str, "force"))
1452 		force_load = 1;
1453 	if (!strcmp(str, "hwp_only"))
1454 		hwp_only = 1;
1455 	return 0;
1456 }
1457 early_param("intel_pstate", intel_pstate_setup);
1458 
1459 MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>");
1460 MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors");
1461 MODULE_LICENSE("GPL");
1462