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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 
15 #include <linux/kernel.h>
16 #include <linux/kernel_stat.h>
17 #include <linux/module.h>
18 #include <linux/ktime.h>
19 #include <linux/hrtimer.h>
20 #include <linux/tick.h>
21 #include <linux/slab.h>
22 #include <linux/sched/cpufreq.h>
23 #include <linux/list.h>
24 #include <linux/cpu.h>
25 #include <linux/cpufreq.h>
26 #include <linux/sysfs.h>
27 #include <linux/types.h>
28 #include <linux/fs.h>
29 #include <linux/acpi.h>
30 #include <linux/vmalloc.h>
31 #include <trace/events/power.h>
32 
33 #include <asm/div64.h>
34 #include <asm/msr.h>
35 #include <asm/cpu_device_id.h>
36 #include <asm/cpufeature.h>
37 #include <asm/intel-family.h>
38 
39 #define INTEL_PSTATE_SAMPLING_INTERVAL	(10 * NSEC_PER_MSEC)
40 
41 #define INTEL_CPUFREQ_TRANSITION_LATENCY	20000
42 #define INTEL_CPUFREQ_TRANSITION_DELAY		500
43 
44 #ifdef CONFIG_ACPI
45 #include <acpi/processor.h>
46 #include <acpi/cppc_acpi.h>
47 #endif
48 
49 #define FRAC_BITS 8
50 #define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
51 #define fp_toint(X) ((X) >> FRAC_BITS)
52 
53 #define EXT_BITS 6
54 #define EXT_FRAC_BITS (EXT_BITS + FRAC_BITS)
55 #define fp_ext_toint(X) ((X) >> EXT_FRAC_BITS)
56 #define int_ext_tofp(X) ((int64_t)(X) << EXT_FRAC_BITS)
57 
58 static inline int32_t mul_fp(int32_t x, int32_t y)
59 {
60 	return ((int64_t)x * (int64_t)y) >> FRAC_BITS;
61 }
62 
63 static inline int32_t div_fp(s64 x, s64 y)
64 {
65 	return div64_s64((int64_t)x << FRAC_BITS, y);
66 }
67 
68 static inline int ceiling_fp(int32_t x)
69 {
70 	int mask, ret;
71 
72 	ret = fp_toint(x);
73 	mask = (1 << FRAC_BITS) - 1;
74 	if (x & mask)
75 		ret += 1;
76 	return ret;
77 }
78 
79 static inline int32_t percent_fp(int percent)
80 {
81 	return div_fp(percent, 100);
82 }
83 
84 static inline u64 mul_ext_fp(u64 x, u64 y)
85 {
86 	return (x * y) >> EXT_FRAC_BITS;
87 }
88 
89 static inline u64 div_ext_fp(u64 x, u64 y)
90 {
91 	return div64_u64(x << EXT_FRAC_BITS, y);
92 }
93 
94 static inline int32_t percent_ext_fp(int percent)
95 {
96 	return div_ext_fp(percent, 100);
97 }
98 
99 /**
100  * struct sample -	Store performance sample
101  * @core_avg_perf:	Ratio of APERF/MPERF which is the actual average
102  *			performance during last sample period
103  * @busy_scaled:	Scaled busy value which is used to calculate next
104  *			P state. This can be different than core_avg_perf
105  *			to account for cpu idle period
106  * @aperf:		Difference of actual performance frequency clock count
107  *			read from APERF MSR between last and current sample
108  * @mperf:		Difference of maximum performance frequency clock count
109  *			read from MPERF MSR between last and current sample
110  * @tsc:		Difference of time stamp counter between last and
111  *			current sample
112  * @time:		Current time from scheduler
113  *
114  * This structure is used in the cpudata structure to store performance sample
115  * data for choosing next P State.
116  */
117 struct sample {
118 	int32_t core_avg_perf;
119 	int32_t busy_scaled;
120 	u64 aperf;
121 	u64 mperf;
122 	u64 tsc;
123 	u64 time;
124 };
125 
126 /**
127  * struct pstate_data - Store P state data
128  * @current_pstate:	Current requested P state
129  * @min_pstate:		Min P state possible for this platform
130  * @max_pstate:		Max P state possible for this platform
131  * @max_pstate_physical:This is physical Max P state for a processor
132  *			This can be higher than the max_pstate which can
133  *			be limited by platform thermal design power limits
134  * @scaling:		Scaling factor to  convert frequency to cpufreq
135  *			frequency units
136  * @turbo_pstate:	Max Turbo P state possible for this platform
137  * @max_freq:		@max_pstate frequency in cpufreq units
138  * @turbo_freq:		@turbo_pstate frequency in cpufreq units
139  *
140  * Stores the per cpu model P state limits and current P state.
141  */
142 struct pstate_data {
143 	int	current_pstate;
144 	int	min_pstate;
145 	int	max_pstate;
146 	int	max_pstate_physical;
147 	int	scaling;
148 	int	turbo_pstate;
149 	unsigned int max_freq;
150 	unsigned int turbo_freq;
151 };
152 
153 /**
154  * struct vid_data -	Stores voltage information data
155  * @min:		VID data for this platform corresponding to
156  *			the lowest P state
157  * @max:		VID data corresponding to the highest P State.
158  * @turbo:		VID data for turbo P state
159  * @ratio:		Ratio of (vid max - vid min) /
160  *			(max P state - Min P State)
161  *
162  * Stores the voltage data for DVFS (Dynamic Voltage and Frequency Scaling)
163  * This data is used in Atom platforms, where in addition to target P state,
164  * the voltage data needs to be specified to select next P State.
165  */
166 struct vid_data {
167 	int min;
168 	int max;
169 	int turbo;
170 	int32_t ratio;
171 };
172 
173 /**
174  * struct global_params - Global parameters, mostly tunable via sysfs.
175  * @no_turbo:		Whether or not to use turbo P-states.
176  * @turbo_disabled:	Whethet or not turbo P-states are available at all,
177  *			based on the MSR_IA32_MISC_ENABLE value and whether or
178  *			not the maximum reported turbo P-state is different from
179  *			the maximum reported non-turbo one.
180  * @min_perf_pct:	Minimum capacity limit in percent of the maximum turbo
181  *			P-state capacity.
182  * @max_perf_pct:	Maximum capacity limit in percent of the maximum turbo
183  *			P-state capacity.
184  */
185 struct global_params {
186 	bool no_turbo;
187 	bool turbo_disabled;
188 	int max_perf_pct;
189 	int min_perf_pct;
190 };
191 
192 /**
193  * struct cpudata -	Per CPU instance data storage
194  * @cpu:		CPU number for this instance data
195  * @policy:		CPUFreq policy value
196  * @update_util:	CPUFreq utility callback information
197  * @update_util_set:	CPUFreq utility callback is set
198  * @iowait_boost:	iowait-related boost fraction
199  * @last_update:	Time of the last update.
200  * @pstate:		Stores P state limits for this CPU
201  * @vid:		Stores VID limits for this CPU
202  * @last_sample_time:	Last Sample time
203  * @aperf_mperf_shift:	Number of clock cycles after aperf, merf is incremented
204  *			This shift is a multiplier to mperf delta to
205  *			calculate CPU busy.
206  * @prev_aperf:		Last APERF value read from APERF MSR
207  * @prev_mperf:		Last MPERF value read from MPERF MSR
208  * @prev_tsc:		Last timestamp counter (TSC) value
209  * @prev_cummulative_iowait: IO Wait time difference from last and
210  *			current sample
211  * @sample:		Storage for storing last Sample data
212  * @min_perf_ratio:	Minimum capacity in terms of PERF or HWP ratios
213  * @max_perf_ratio:	Maximum capacity in terms of PERF or HWP ratios
214  * @acpi_perf_data:	Stores ACPI perf information read from _PSS
215  * @valid_pss_table:	Set to true for valid ACPI _PSS entries found
216  * @epp_powersave:	Last saved HWP energy performance preference
217  *			(EPP) or energy performance bias (EPB),
218  *			when policy switched to performance
219  * @epp_policy:		Last saved policy used to set EPP/EPB
220  * @epp_default:	Power on default HWP energy performance
221  *			preference/bias
222  * @epp_saved:		Saved EPP/EPB during system suspend or CPU offline
223  *			operation
224  * @hwp_req_cached:	Cached value of the last HWP Request MSR
225  * @hwp_cap_cached:	Cached value of the last HWP Capabilities MSR
226  * @last_io_update:	Last time when IO wake flag was set
227  * @sched_flags:	Store scheduler flags for possible cross CPU update
228  * @hwp_boost_min:	Last HWP boosted min performance
229  *
230  * This structure stores per CPU instance data for all CPUs.
231  */
232 struct cpudata {
233 	int cpu;
234 
235 	unsigned int policy;
236 	struct update_util_data update_util;
237 	bool   update_util_set;
238 
239 	struct pstate_data pstate;
240 	struct vid_data vid;
241 
242 	u64	last_update;
243 	u64	last_sample_time;
244 	u64	aperf_mperf_shift;
245 	u64	prev_aperf;
246 	u64	prev_mperf;
247 	u64	prev_tsc;
248 	u64	prev_cummulative_iowait;
249 	struct sample sample;
250 	int32_t	min_perf_ratio;
251 	int32_t	max_perf_ratio;
252 #ifdef CONFIG_ACPI
253 	struct acpi_processor_performance acpi_perf_data;
254 	bool valid_pss_table;
255 #endif
256 	unsigned int iowait_boost;
257 	s16 epp_powersave;
258 	s16 epp_policy;
259 	s16 epp_default;
260 	s16 epp_saved;
261 	u64 hwp_req_cached;
262 	u64 hwp_cap_cached;
263 	u64 last_io_update;
264 	unsigned int sched_flags;
265 	u32 hwp_boost_min;
266 };
267 
268 static struct cpudata **all_cpu_data;
269 
270 /**
271  * struct pstate_funcs - Per CPU model specific callbacks
272  * @get_max:		Callback to get maximum non turbo effective P state
273  * @get_max_physical:	Callback to get maximum non turbo physical P state
274  * @get_min:		Callback to get minimum P state
275  * @get_turbo:		Callback to get turbo P state
276  * @get_scaling:	Callback to get frequency scaling factor
277  * @get_val:		Callback to convert P state to actual MSR write value
278  * @get_vid:		Callback to get VID data for Atom platforms
279  *
280  * Core and Atom CPU models have different way to get P State limits. This
281  * structure is used to store those callbacks.
282  */
283 struct pstate_funcs {
284 	int (*get_max)(void);
285 	int (*get_max_physical)(void);
286 	int (*get_min)(void);
287 	int (*get_turbo)(void);
288 	int (*get_scaling)(void);
289 	int (*get_aperf_mperf_shift)(void);
290 	u64 (*get_val)(struct cpudata*, int pstate);
291 	void (*get_vid)(struct cpudata *);
292 };
293 
294 static struct pstate_funcs pstate_funcs __read_mostly;
295 
296 static int hwp_active __read_mostly;
297 static bool per_cpu_limits __read_mostly;
298 static bool hwp_boost __read_mostly;
299 
300 static struct cpufreq_driver *intel_pstate_driver __read_mostly;
301 
302 #ifdef CONFIG_ACPI
303 static bool acpi_ppc;
304 #endif
305 
306 static struct global_params global;
307 
308 static DEFINE_MUTEX(intel_pstate_driver_lock);
309 static DEFINE_MUTEX(intel_pstate_limits_lock);
310 
311 #ifdef CONFIG_ACPI
312 
313 static bool intel_pstate_get_ppc_enable_status(void)
314 {
315 	if (acpi_gbl_FADT.preferred_profile == PM_ENTERPRISE_SERVER ||
316 	    acpi_gbl_FADT.preferred_profile == PM_PERFORMANCE_SERVER)
317 		return true;
318 
319 	return acpi_ppc;
320 }
321 
322 #ifdef CONFIG_ACPI_CPPC_LIB
323 
324 /* The work item is needed to avoid CPU hotplug locking issues */
325 static void intel_pstste_sched_itmt_work_fn(struct work_struct *work)
326 {
327 	sched_set_itmt_support();
328 }
329 
330 static DECLARE_WORK(sched_itmt_work, intel_pstste_sched_itmt_work_fn);
331 
332 static void intel_pstate_set_itmt_prio(int cpu)
333 {
334 	struct cppc_perf_caps cppc_perf;
335 	static u32 max_highest_perf = 0, min_highest_perf = U32_MAX;
336 	int ret;
337 
338 	ret = cppc_get_perf_caps(cpu, &cppc_perf);
339 	if (ret)
340 		return;
341 
342 	/*
343 	 * The priorities can be set regardless of whether or not
344 	 * sched_set_itmt_support(true) has been called and it is valid to
345 	 * update them at any time after it has been called.
346 	 */
347 	sched_set_itmt_core_prio(cppc_perf.highest_perf, cpu);
348 
349 	if (max_highest_perf <= min_highest_perf) {
350 		if (cppc_perf.highest_perf > max_highest_perf)
351 			max_highest_perf = cppc_perf.highest_perf;
352 
353 		if (cppc_perf.highest_perf < min_highest_perf)
354 			min_highest_perf = cppc_perf.highest_perf;
355 
356 		if (max_highest_perf > min_highest_perf) {
357 			/*
358 			 * This code can be run during CPU online under the
359 			 * CPU hotplug locks, so sched_set_itmt_support()
360 			 * cannot be called from here.  Queue up a work item
361 			 * to invoke it.
362 			 */
363 			schedule_work(&sched_itmt_work);
364 		}
365 	}
366 }
367 #else
368 static void intel_pstate_set_itmt_prio(int cpu)
369 {
370 }
371 #endif
372 
373 static void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy)
374 {
375 	struct cpudata *cpu;
376 	int ret;
377 	int i;
378 
379 	if (hwp_active) {
380 		intel_pstate_set_itmt_prio(policy->cpu);
381 		return;
382 	}
383 
384 	if (!intel_pstate_get_ppc_enable_status())
385 		return;
386 
387 	cpu = all_cpu_data[policy->cpu];
388 
389 	ret = acpi_processor_register_performance(&cpu->acpi_perf_data,
390 						  policy->cpu);
391 	if (ret)
392 		return;
393 
394 	/*
395 	 * Check if the control value in _PSS is for PERF_CTL MSR, which should
396 	 * guarantee that the states returned by it map to the states in our
397 	 * list directly.
398 	 */
399 	if (cpu->acpi_perf_data.control_register.space_id !=
400 						ACPI_ADR_SPACE_FIXED_HARDWARE)
401 		goto err;
402 
403 	/*
404 	 * If there is only one entry _PSS, simply ignore _PSS and continue as
405 	 * usual without taking _PSS into account
406 	 */
407 	if (cpu->acpi_perf_data.state_count < 2)
408 		goto err;
409 
410 	pr_debug("CPU%u - ACPI _PSS perf data\n", policy->cpu);
411 	for (i = 0; i < cpu->acpi_perf_data.state_count; i++) {
412 		pr_debug("     %cP%d: %u MHz, %u mW, 0x%x\n",
413 			 (i == cpu->acpi_perf_data.state ? '*' : ' '), i,
414 			 (u32) cpu->acpi_perf_data.states[i].core_frequency,
415 			 (u32) cpu->acpi_perf_data.states[i].power,
416 			 (u32) cpu->acpi_perf_data.states[i].control);
417 	}
418 
419 	/*
420 	 * The _PSS table doesn't contain whole turbo frequency range.
421 	 * This just contains +1 MHZ above the max non turbo frequency,
422 	 * with control value corresponding to max turbo ratio. But
423 	 * when cpufreq set policy is called, it will call with this
424 	 * max frequency, which will cause a reduced performance as
425 	 * this driver uses real max turbo frequency as the max
426 	 * frequency. So correct this frequency in _PSS table to
427 	 * correct max turbo frequency based on the turbo state.
428 	 * Also need to convert to MHz as _PSS freq is in MHz.
429 	 */
430 	if (!global.turbo_disabled)
431 		cpu->acpi_perf_data.states[0].core_frequency =
432 					policy->cpuinfo.max_freq / 1000;
433 	cpu->valid_pss_table = true;
434 	pr_debug("_PPC limits will be enforced\n");
435 
436 	return;
437 
438  err:
439 	cpu->valid_pss_table = false;
440 	acpi_processor_unregister_performance(policy->cpu);
441 }
442 
443 static void intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
444 {
445 	struct cpudata *cpu;
446 
447 	cpu = all_cpu_data[policy->cpu];
448 	if (!cpu->valid_pss_table)
449 		return;
450 
451 	acpi_processor_unregister_performance(policy->cpu);
452 }
453 #else
454 static inline void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy)
455 {
456 }
457 
458 static inline void intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
459 {
460 }
461 #endif
462 
463 static inline void update_turbo_state(void)
464 {
465 	u64 misc_en;
466 	struct cpudata *cpu;
467 
468 	cpu = all_cpu_data[0];
469 	rdmsrl(MSR_IA32_MISC_ENABLE, misc_en);
470 	global.turbo_disabled =
471 		(misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE ||
472 		 cpu->pstate.max_pstate == cpu->pstate.turbo_pstate);
473 }
474 
475 static int min_perf_pct_min(void)
476 {
477 	struct cpudata *cpu = all_cpu_data[0];
478 	int turbo_pstate = cpu->pstate.turbo_pstate;
479 
480 	return turbo_pstate ?
481 		(cpu->pstate.min_pstate * 100 / turbo_pstate) : 0;
482 }
483 
484 static s16 intel_pstate_get_epb(struct cpudata *cpu_data)
485 {
486 	u64 epb;
487 	int ret;
488 
489 	if (!static_cpu_has(X86_FEATURE_EPB))
490 		return -ENXIO;
491 
492 	ret = rdmsrl_on_cpu(cpu_data->cpu, MSR_IA32_ENERGY_PERF_BIAS, &epb);
493 	if (ret)
494 		return (s16)ret;
495 
496 	return (s16)(epb & 0x0f);
497 }
498 
499 static s16 intel_pstate_get_epp(struct cpudata *cpu_data, u64 hwp_req_data)
500 {
501 	s16 epp;
502 
503 	if (static_cpu_has(X86_FEATURE_HWP_EPP)) {
504 		/*
505 		 * When hwp_req_data is 0, means that caller didn't read
506 		 * MSR_HWP_REQUEST, so need to read and get EPP.
507 		 */
508 		if (!hwp_req_data) {
509 			epp = rdmsrl_on_cpu(cpu_data->cpu, MSR_HWP_REQUEST,
510 					    &hwp_req_data);
511 			if (epp)
512 				return epp;
513 		}
514 		epp = (hwp_req_data >> 24) & 0xff;
515 	} else {
516 		/* When there is no EPP present, HWP uses EPB settings */
517 		epp = intel_pstate_get_epb(cpu_data);
518 	}
519 
520 	return epp;
521 }
522 
523 static int intel_pstate_set_epb(int cpu, s16 pref)
524 {
525 	u64 epb;
526 	int ret;
527 
528 	if (!static_cpu_has(X86_FEATURE_EPB))
529 		return -ENXIO;
530 
531 	ret = rdmsrl_on_cpu(cpu, MSR_IA32_ENERGY_PERF_BIAS, &epb);
532 	if (ret)
533 		return ret;
534 
535 	epb = (epb & ~0x0f) | pref;
536 	wrmsrl_on_cpu(cpu, MSR_IA32_ENERGY_PERF_BIAS, epb);
537 
538 	return 0;
539 }
540 
541 /*
542  * EPP/EPB display strings corresponding to EPP index in the
543  * energy_perf_strings[]
544  *	index		String
545  *-------------------------------------
546  *	0		default
547  *	1		performance
548  *	2		balance_performance
549  *	3		balance_power
550  *	4		power
551  */
552 static const char * const energy_perf_strings[] = {
553 	"default",
554 	"performance",
555 	"balance_performance",
556 	"balance_power",
557 	"power",
558 	NULL
559 };
560 static const unsigned int epp_values[] = {
561 	HWP_EPP_PERFORMANCE,
562 	HWP_EPP_BALANCE_PERFORMANCE,
563 	HWP_EPP_BALANCE_POWERSAVE,
564 	HWP_EPP_POWERSAVE
565 };
566 
567 static int intel_pstate_get_energy_pref_index(struct cpudata *cpu_data)
568 {
569 	s16 epp;
570 	int index = -EINVAL;
571 
572 	epp = intel_pstate_get_epp(cpu_data, 0);
573 	if (epp < 0)
574 		return epp;
575 
576 	if (static_cpu_has(X86_FEATURE_HWP_EPP)) {
577 		if (epp == HWP_EPP_PERFORMANCE)
578 			return 1;
579 		if (epp <= HWP_EPP_BALANCE_PERFORMANCE)
580 			return 2;
581 		if (epp <= HWP_EPP_BALANCE_POWERSAVE)
582 			return 3;
583 		else
584 			return 4;
585 	} else if (static_cpu_has(X86_FEATURE_EPB)) {
586 		/*
587 		 * Range:
588 		 *	0x00-0x03	:	Performance
589 		 *	0x04-0x07	:	Balance performance
590 		 *	0x08-0x0B	:	Balance power
591 		 *	0x0C-0x0F	:	Power
592 		 * The EPB is a 4 bit value, but our ranges restrict the
593 		 * value which can be set. Here only using top two bits
594 		 * effectively.
595 		 */
596 		index = (epp >> 2) + 1;
597 	}
598 
599 	return index;
600 }
601 
602 static int intel_pstate_set_energy_pref_index(struct cpudata *cpu_data,
603 					      int pref_index)
604 {
605 	int epp = -EINVAL;
606 	int ret;
607 
608 	if (!pref_index)
609 		epp = cpu_data->epp_default;
610 
611 	mutex_lock(&intel_pstate_limits_lock);
612 
613 	if (static_cpu_has(X86_FEATURE_HWP_EPP)) {
614 		u64 value;
615 
616 		ret = rdmsrl_on_cpu(cpu_data->cpu, MSR_HWP_REQUEST, &value);
617 		if (ret)
618 			goto return_pref;
619 
620 		value &= ~GENMASK_ULL(31, 24);
621 
622 		if (epp == -EINVAL)
623 			epp = epp_values[pref_index - 1];
624 
625 		value |= (u64)epp << 24;
626 		ret = wrmsrl_on_cpu(cpu_data->cpu, MSR_HWP_REQUEST, value);
627 	} else {
628 		if (epp == -EINVAL)
629 			epp = (pref_index - 1) << 2;
630 		ret = intel_pstate_set_epb(cpu_data->cpu, epp);
631 	}
632 return_pref:
633 	mutex_unlock(&intel_pstate_limits_lock);
634 
635 	return ret;
636 }
637 
638 static ssize_t show_energy_performance_available_preferences(
639 				struct cpufreq_policy *policy, char *buf)
640 {
641 	int i = 0;
642 	int ret = 0;
643 
644 	while (energy_perf_strings[i] != NULL)
645 		ret += sprintf(&buf[ret], "%s ", energy_perf_strings[i++]);
646 
647 	ret += sprintf(&buf[ret], "\n");
648 
649 	return ret;
650 }
651 
652 cpufreq_freq_attr_ro(energy_performance_available_preferences);
653 
654 static ssize_t store_energy_performance_preference(
655 		struct cpufreq_policy *policy, const char *buf, size_t count)
656 {
657 	struct cpudata *cpu_data = all_cpu_data[policy->cpu];
658 	char str_preference[21];
659 	int ret, i = 0;
660 
661 	ret = sscanf(buf, "%20s", str_preference);
662 	if (ret != 1)
663 		return -EINVAL;
664 
665 	while (energy_perf_strings[i] != NULL) {
666 		if (!strcmp(str_preference, energy_perf_strings[i])) {
667 			intel_pstate_set_energy_pref_index(cpu_data, i);
668 			return count;
669 		}
670 		++i;
671 	}
672 
673 	return -EINVAL;
674 }
675 
676 static ssize_t show_energy_performance_preference(
677 				struct cpufreq_policy *policy, char *buf)
678 {
679 	struct cpudata *cpu_data = all_cpu_data[policy->cpu];
680 	int preference;
681 
682 	preference = intel_pstate_get_energy_pref_index(cpu_data);
683 	if (preference < 0)
684 		return preference;
685 
686 	return  sprintf(buf, "%s\n", energy_perf_strings[preference]);
687 }
688 
689 cpufreq_freq_attr_rw(energy_performance_preference);
690 
691 static struct freq_attr *hwp_cpufreq_attrs[] = {
692 	&energy_performance_preference,
693 	&energy_performance_available_preferences,
694 	NULL,
695 };
696 
697 static void intel_pstate_get_hwp_max(unsigned int cpu, int *phy_max,
698 				     int *current_max)
699 {
700 	u64 cap;
701 
702 	rdmsrl_on_cpu(cpu, MSR_HWP_CAPABILITIES, &cap);
703 	WRITE_ONCE(all_cpu_data[cpu]->hwp_cap_cached, cap);
704 	if (global.no_turbo)
705 		*current_max = HWP_GUARANTEED_PERF(cap);
706 	else
707 		*current_max = HWP_HIGHEST_PERF(cap);
708 
709 	*phy_max = HWP_HIGHEST_PERF(cap);
710 }
711 
712 static void intel_pstate_hwp_set(unsigned int cpu)
713 {
714 	struct cpudata *cpu_data = all_cpu_data[cpu];
715 	int max, min;
716 	u64 value;
717 	s16 epp;
718 
719 	max = cpu_data->max_perf_ratio;
720 	min = cpu_data->min_perf_ratio;
721 
722 	if (cpu_data->policy == CPUFREQ_POLICY_PERFORMANCE)
723 		min = max;
724 
725 	rdmsrl_on_cpu(cpu, MSR_HWP_REQUEST, &value);
726 
727 	value &= ~HWP_MIN_PERF(~0L);
728 	value |= HWP_MIN_PERF(min);
729 
730 	value &= ~HWP_MAX_PERF(~0L);
731 	value |= HWP_MAX_PERF(max);
732 
733 	if (cpu_data->epp_policy == cpu_data->policy)
734 		goto skip_epp;
735 
736 	cpu_data->epp_policy = cpu_data->policy;
737 
738 	if (cpu_data->epp_saved >= 0) {
739 		epp = cpu_data->epp_saved;
740 		cpu_data->epp_saved = -EINVAL;
741 		goto update_epp;
742 	}
743 
744 	if (cpu_data->policy == CPUFREQ_POLICY_PERFORMANCE) {
745 		epp = intel_pstate_get_epp(cpu_data, value);
746 		cpu_data->epp_powersave = epp;
747 		/* If EPP read was failed, then don't try to write */
748 		if (epp < 0)
749 			goto skip_epp;
750 
751 		epp = 0;
752 	} else {
753 		/* skip setting EPP, when saved value is invalid */
754 		if (cpu_data->epp_powersave < 0)
755 			goto skip_epp;
756 
757 		/*
758 		 * No need to restore EPP when it is not zero. This
759 		 * means:
760 		 *  - Policy is not changed
761 		 *  - user has manually changed
762 		 *  - Error reading EPB
763 		 */
764 		epp = intel_pstate_get_epp(cpu_data, value);
765 		if (epp)
766 			goto skip_epp;
767 
768 		epp = cpu_data->epp_powersave;
769 	}
770 update_epp:
771 	if (static_cpu_has(X86_FEATURE_HWP_EPP)) {
772 		value &= ~GENMASK_ULL(31, 24);
773 		value |= (u64)epp << 24;
774 	} else {
775 		intel_pstate_set_epb(cpu, epp);
776 	}
777 skip_epp:
778 	WRITE_ONCE(cpu_data->hwp_req_cached, value);
779 	wrmsrl_on_cpu(cpu, MSR_HWP_REQUEST, value);
780 }
781 
782 static int intel_pstate_hwp_save_state(struct cpufreq_policy *policy)
783 {
784 	struct cpudata *cpu_data = all_cpu_data[policy->cpu];
785 
786 	if (!hwp_active)
787 		return 0;
788 
789 	cpu_data->epp_saved = intel_pstate_get_epp(cpu_data, 0);
790 
791 	return 0;
792 }
793 
794 static void intel_pstate_hwp_enable(struct cpudata *cpudata);
795 
796 static int intel_pstate_resume(struct cpufreq_policy *policy)
797 {
798 	if (!hwp_active)
799 		return 0;
800 
801 	mutex_lock(&intel_pstate_limits_lock);
802 
803 	if (policy->cpu == 0)
804 		intel_pstate_hwp_enable(all_cpu_data[policy->cpu]);
805 
806 	all_cpu_data[policy->cpu]->epp_policy = 0;
807 	intel_pstate_hwp_set(policy->cpu);
808 
809 	mutex_unlock(&intel_pstate_limits_lock);
810 
811 	return 0;
812 }
813 
814 static void intel_pstate_update_policies(void)
815 {
816 	int cpu;
817 
818 	for_each_possible_cpu(cpu)
819 		cpufreq_update_policy(cpu);
820 }
821 
822 /************************** sysfs begin ************************/
823 #define show_one(file_name, object)					\
824 	static ssize_t show_##file_name					\
825 	(struct kobject *kobj, struct attribute *attr, char *buf)	\
826 	{								\
827 		return sprintf(buf, "%u\n", global.object);		\
828 	}
829 
830 static ssize_t intel_pstate_show_status(char *buf);
831 static int intel_pstate_update_status(const char *buf, size_t size);
832 
833 static ssize_t show_status(struct kobject *kobj,
834 			   struct attribute *attr, char *buf)
835 {
836 	ssize_t ret;
837 
838 	mutex_lock(&intel_pstate_driver_lock);
839 	ret = intel_pstate_show_status(buf);
840 	mutex_unlock(&intel_pstate_driver_lock);
841 
842 	return ret;
843 }
844 
845 static ssize_t store_status(struct kobject *a, struct attribute *b,
846 			    const char *buf, size_t count)
847 {
848 	char *p = memchr(buf, '\n', count);
849 	int ret;
850 
851 	mutex_lock(&intel_pstate_driver_lock);
852 	ret = intel_pstate_update_status(buf, p ? p - buf : count);
853 	mutex_unlock(&intel_pstate_driver_lock);
854 
855 	return ret < 0 ? ret : count;
856 }
857 
858 static ssize_t show_turbo_pct(struct kobject *kobj,
859 				struct attribute *attr, char *buf)
860 {
861 	struct cpudata *cpu;
862 	int total, no_turbo, turbo_pct;
863 	uint32_t turbo_fp;
864 
865 	mutex_lock(&intel_pstate_driver_lock);
866 
867 	if (!intel_pstate_driver) {
868 		mutex_unlock(&intel_pstate_driver_lock);
869 		return -EAGAIN;
870 	}
871 
872 	cpu = all_cpu_data[0];
873 
874 	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
875 	no_turbo = cpu->pstate.max_pstate - cpu->pstate.min_pstate + 1;
876 	turbo_fp = div_fp(no_turbo, total);
877 	turbo_pct = 100 - fp_toint(mul_fp(turbo_fp, int_tofp(100)));
878 
879 	mutex_unlock(&intel_pstate_driver_lock);
880 
881 	return sprintf(buf, "%u\n", turbo_pct);
882 }
883 
884 static ssize_t show_num_pstates(struct kobject *kobj,
885 				struct attribute *attr, char *buf)
886 {
887 	struct cpudata *cpu;
888 	int total;
889 
890 	mutex_lock(&intel_pstate_driver_lock);
891 
892 	if (!intel_pstate_driver) {
893 		mutex_unlock(&intel_pstate_driver_lock);
894 		return -EAGAIN;
895 	}
896 
897 	cpu = all_cpu_data[0];
898 	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
899 
900 	mutex_unlock(&intel_pstate_driver_lock);
901 
902 	return sprintf(buf, "%u\n", total);
903 }
904 
905 static ssize_t show_no_turbo(struct kobject *kobj,
906 			     struct attribute *attr, char *buf)
907 {
908 	ssize_t ret;
909 
910 	mutex_lock(&intel_pstate_driver_lock);
911 
912 	if (!intel_pstate_driver) {
913 		mutex_unlock(&intel_pstate_driver_lock);
914 		return -EAGAIN;
915 	}
916 
917 	update_turbo_state();
918 	if (global.turbo_disabled)
919 		ret = sprintf(buf, "%u\n", global.turbo_disabled);
920 	else
921 		ret = sprintf(buf, "%u\n", global.no_turbo);
922 
923 	mutex_unlock(&intel_pstate_driver_lock);
924 
925 	return ret;
926 }
927 
928 static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
929 			      const char *buf, size_t count)
930 {
931 	unsigned int input;
932 	int ret;
933 
934 	ret = sscanf(buf, "%u", &input);
935 	if (ret != 1)
936 		return -EINVAL;
937 
938 	mutex_lock(&intel_pstate_driver_lock);
939 
940 	if (!intel_pstate_driver) {
941 		mutex_unlock(&intel_pstate_driver_lock);
942 		return -EAGAIN;
943 	}
944 
945 	mutex_lock(&intel_pstate_limits_lock);
946 
947 	update_turbo_state();
948 	if (global.turbo_disabled) {
949 		pr_warn("Turbo disabled by BIOS or unavailable on processor\n");
950 		mutex_unlock(&intel_pstate_limits_lock);
951 		mutex_unlock(&intel_pstate_driver_lock);
952 		return -EPERM;
953 	}
954 
955 	global.no_turbo = clamp_t(int, input, 0, 1);
956 
957 	if (global.no_turbo) {
958 		struct cpudata *cpu = all_cpu_data[0];
959 		int pct = cpu->pstate.max_pstate * 100 / cpu->pstate.turbo_pstate;
960 
961 		/* Squash the global minimum into the permitted range. */
962 		if (global.min_perf_pct > pct)
963 			global.min_perf_pct = pct;
964 	}
965 
966 	mutex_unlock(&intel_pstate_limits_lock);
967 
968 	intel_pstate_update_policies();
969 
970 	mutex_unlock(&intel_pstate_driver_lock);
971 
972 	return count;
973 }
974 
975 static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
976 				  const char *buf, size_t count)
977 {
978 	unsigned int input;
979 	int ret;
980 
981 	ret = sscanf(buf, "%u", &input);
982 	if (ret != 1)
983 		return -EINVAL;
984 
985 	mutex_lock(&intel_pstate_driver_lock);
986 
987 	if (!intel_pstate_driver) {
988 		mutex_unlock(&intel_pstate_driver_lock);
989 		return -EAGAIN;
990 	}
991 
992 	mutex_lock(&intel_pstate_limits_lock);
993 
994 	global.max_perf_pct = clamp_t(int, input, global.min_perf_pct, 100);
995 
996 	mutex_unlock(&intel_pstate_limits_lock);
997 
998 	intel_pstate_update_policies();
999 
1000 	mutex_unlock(&intel_pstate_driver_lock);
1001 
1002 	return count;
1003 }
1004 
1005 static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
1006 				  const char *buf, size_t count)
1007 {
1008 	unsigned int input;
1009 	int ret;
1010 
1011 	ret = sscanf(buf, "%u", &input);
1012 	if (ret != 1)
1013 		return -EINVAL;
1014 
1015 	mutex_lock(&intel_pstate_driver_lock);
1016 
1017 	if (!intel_pstate_driver) {
1018 		mutex_unlock(&intel_pstate_driver_lock);
1019 		return -EAGAIN;
1020 	}
1021 
1022 	mutex_lock(&intel_pstate_limits_lock);
1023 
1024 	global.min_perf_pct = clamp_t(int, input,
1025 				      min_perf_pct_min(), global.max_perf_pct);
1026 
1027 	mutex_unlock(&intel_pstate_limits_lock);
1028 
1029 	intel_pstate_update_policies();
1030 
1031 	mutex_unlock(&intel_pstate_driver_lock);
1032 
1033 	return count;
1034 }
1035 
1036 static ssize_t show_hwp_dynamic_boost(struct kobject *kobj,
1037 				struct attribute *attr, char *buf)
1038 {
1039 	return sprintf(buf, "%u\n", hwp_boost);
1040 }
1041 
1042 static ssize_t store_hwp_dynamic_boost(struct kobject *a, struct attribute *b,
1043 				       const char *buf, size_t count)
1044 {
1045 	unsigned int input;
1046 	int ret;
1047 
1048 	ret = kstrtouint(buf, 10, &input);
1049 	if (ret)
1050 		return ret;
1051 
1052 	mutex_lock(&intel_pstate_driver_lock);
1053 	hwp_boost = !!input;
1054 	intel_pstate_update_policies();
1055 	mutex_unlock(&intel_pstate_driver_lock);
1056 
1057 	return count;
1058 }
1059 
1060 show_one(max_perf_pct, max_perf_pct);
1061 show_one(min_perf_pct, min_perf_pct);
1062 
1063 define_one_global_rw(status);
1064 define_one_global_rw(no_turbo);
1065 define_one_global_rw(max_perf_pct);
1066 define_one_global_rw(min_perf_pct);
1067 define_one_global_ro(turbo_pct);
1068 define_one_global_ro(num_pstates);
1069 define_one_global_rw(hwp_dynamic_boost);
1070 
1071 static struct attribute *intel_pstate_attributes[] = {
1072 	&status.attr,
1073 	&no_turbo.attr,
1074 	&turbo_pct.attr,
1075 	&num_pstates.attr,
1076 	NULL
1077 };
1078 
1079 static const struct attribute_group intel_pstate_attr_group = {
1080 	.attrs = intel_pstate_attributes,
1081 };
1082 
1083 static void __init intel_pstate_sysfs_expose_params(void)
1084 {
1085 	struct kobject *intel_pstate_kobject;
1086 	int rc;
1087 
1088 	intel_pstate_kobject = kobject_create_and_add("intel_pstate",
1089 						&cpu_subsys.dev_root->kobj);
1090 	if (WARN_ON(!intel_pstate_kobject))
1091 		return;
1092 
1093 	rc = sysfs_create_group(intel_pstate_kobject, &intel_pstate_attr_group);
1094 	if (WARN_ON(rc))
1095 		return;
1096 
1097 	/*
1098 	 * If per cpu limits are enforced there are no global limits, so
1099 	 * return without creating max/min_perf_pct attributes
1100 	 */
1101 	if (per_cpu_limits)
1102 		return;
1103 
1104 	rc = sysfs_create_file(intel_pstate_kobject, &max_perf_pct.attr);
1105 	WARN_ON(rc);
1106 
1107 	rc = sysfs_create_file(intel_pstate_kobject, &min_perf_pct.attr);
1108 	WARN_ON(rc);
1109 
1110 	if (hwp_active) {
1111 		rc = sysfs_create_file(intel_pstate_kobject,
1112 				       &hwp_dynamic_boost.attr);
1113 		WARN_ON(rc);
1114 	}
1115 }
1116 /************************** sysfs end ************************/
1117 
1118 static void intel_pstate_hwp_enable(struct cpudata *cpudata)
1119 {
1120 	/* First disable HWP notification interrupt as we don't process them */
1121 	if (static_cpu_has(X86_FEATURE_HWP_NOTIFY))
1122 		wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_INTERRUPT, 0x00);
1123 
1124 	wrmsrl_on_cpu(cpudata->cpu, MSR_PM_ENABLE, 0x1);
1125 	cpudata->epp_policy = 0;
1126 	if (cpudata->epp_default == -EINVAL)
1127 		cpudata->epp_default = intel_pstate_get_epp(cpudata, 0);
1128 }
1129 
1130 #define MSR_IA32_POWER_CTL_BIT_EE	19
1131 
1132 /* Disable energy efficiency optimization */
1133 static void intel_pstate_disable_ee(int cpu)
1134 {
1135 	u64 power_ctl;
1136 	int ret;
1137 
1138 	ret = rdmsrl_on_cpu(cpu, MSR_IA32_POWER_CTL, &power_ctl);
1139 	if (ret)
1140 		return;
1141 
1142 	if (!(power_ctl & BIT(MSR_IA32_POWER_CTL_BIT_EE))) {
1143 		pr_info("Disabling energy efficiency optimization\n");
1144 		power_ctl |= BIT(MSR_IA32_POWER_CTL_BIT_EE);
1145 		wrmsrl_on_cpu(cpu, MSR_IA32_POWER_CTL, power_ctl);
1146 	}
1147 }
1148 
1149 static int atom_get_min_pstate(void)
1150 {
1151 	u64 value;
1152 
1153 	rdmsrl(MSR_ATOM_CORE_RATIOS, value);
1154 	return (value >> 8) & 0x7F;
1155 }
1156 
1157 static int atom_get_max_pstate(void)
1158 {
1159 	u64 value;
1160 
1161 	rdmsrl(MSR_ATOM_CORE_RATIOS, value);
1162 	return (value >> 16) & 0x7F;
1163 }
1164 
1165 static int atom_get_turbo_pstate(void)
1166 {
1167 	u64 value;
1168 
1169 	rdmsrl(MSR_ATOM_CORE_TURBO_RATIOS, value);
1170 	return value & 0x7F;
1171 }
1172 
1173 static u64 atom_get_val(struct cpudata *cpudata, int pstate)
1174 {
1175 	u64 val;
1176 	int32_t vid_fp;
1177 	u32 vid;
1178 
1179 	val = (u64)pstate << 8;
1180 	if (global.no_turbo && !global.turbo_disabled)
1181 		val |= (u64)1 << 32;
1182 
1183 	vid_fp = cpudata->vid.min + mul_fp(
1184 		int_tofp(pstate - cpudata->pstate.min_pstate),
1185 		cpudata->vid.ratio);
1186 
1187 	vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
1188 	vid = ceiling_fp(vid_fp);
1189 
1190 	if (pstate > cpudata->pstate.max_pstate)
1191 		vid = cpudata->vid.turbo;
1192 
1193 	return val | vid;
1194 }
1195 
1196 static int silvermont_get_scaling(void)
1197 {
1198 	u64 value;
1199 	int i;
1200 	/* Defined in Table 35-6 from SDM (Sept 2015) */
1201 	static int silvermont_freq_table[] = {
1202 		83300, 100000, 133300, 116700, 80000};
1203 
1204 	rdmsrl(MSR_FSB_FREQ, value);
1205 	i = value & 0x7;
1206 	WARN_ON(i > 4);
1207 
1208 	return silvermont_freq_table[i];
1209 }
1210 
1211 static int airmont_get_scaling(void)
1212 {
1213 	u64 value;
1214 	int i;
1215 	/* Defined in Table 35-10 from SDM (Sept 2015) */
1216 	static int airmont_freq_table[] = {
1217 		83300, 100000, 133300, 116700, 80000,
1218 		93300, 90000, 88900, 87500};
1219 
1220 	rdmsrl(MSR_FSB_FREQ, value);
1221 	i = value & 0xF;
1222 	WARN_ON(i > 8);
1223 
1224 	return airmont_freq_table[i];
1225 }
1226 
1227 static void atom_get_vid(struct cpudata *cpudata)
1228 {
1229 	u64 value;
1230 
1231 	rdmsrl(MSR_ATOM_CORE_VIDS, value);
1232 	cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
1233 	cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
1234 	cpudata->vid.ratio = div_fp(
1235 		cpudata->vid.max - cpudata->vid.min,
1236 		int_tofp(cpudata->pstate.max_pstate -
1237 			cpudata->pstate.min_pstate));
1238 
1239 	rdmsrl(MSR_ATOM_CORE_TURBO_VIDS, value);
1240 	cpudata->vid.turbo = value & 0x7f;
1241 }
1242 
1243 static int core_get_min_pstate(void)
1244 {
1245 	u64 value;
1246 
1247 	rdmsrl(MSR_PLATFORM_INFO, value);
1248 	return (value >> 40) & 0xFF;
1249 }
1250 
1251 static int core_get_max_pstate_physical(void)
1252 {
1253 	u64 value;
1254 
1255 	rdmsrl(MSR_PLATFORM_INFO, value);
1256 	return (value >> 8) & 0xFF;
1257 }
1258 
1259 static int core_get_tdp_ratio(u64 plat_info)
1260 {
1261 	/* Check how many TDP levels present */
1262 	if (plat_info & 0x600000000) {
1263 		u64 tdp_ctrl;
1264 		u64 tdp_ratio;
1265 		int tdp_msr;
1266 		int err;
1267 
1268 		/* Get the TDP level (0, 1, 2) to get ratios */
1269 		err = rdmsrl_safe(MSR_CONFIG_TDP_CONTROL, &tdp_ctrl);
1270 		if (err)
1271 			return err;
1272 
1273 		/* TDP MSR are continuous starting at 0x648 */
1274 		tdp_msr = MSR_CONFIG_TDP_NOMINAL + (tdp_ctrl & 0x03);
1275 		err = rdmsrl_safe(tdp_msr, &tdp_ratio);
1276 		if (err)
1277 			return err;
1278 
1279 		/* For level 1 and 2, bits[23:16] contain the ratio */
1280 		if (tdp_ctrl & 0x03)
1281 			tdp_ratio >>= 16;
1282 
1283 		tdp_ratio &= 0xff; /* ratios are only 8 bits long */
1284 		pr_debug("tdp_ratio %x\n", (int)tdp_ratio);
1285 
1286 		return (int)tdp_ratio;
1287 	}
1288 
1289 	return -ENXIO;
1290 }
1291 
1292 static int core_get_max_pstate(void)
1293 {
1294 	u64 tar;
1295 	u64 plat_info;
1296 	int max_pstate;
1297 	int tdp_ratio;
1298 	int err;
1299 
1300 	rdmsrl(MSR_PLATFORM_INFO, plat_info);
1301 	max_pstate = (plat_info >> 8) & 0xFF;
1302 
1303 	tdp_ratio = core_get_tdp_ratio(plat_info);
1304 	if (tdp_ratio <= 0)
1305 		return max_pstate;
1306 
1307 	if (hwp_active) {
1308 		/* Turbo activation ratio is not used on HWP platforms */
1309 		return tdp_ratio;
1310 	}
1311 
1312 	err = rdmsrl_safe(MSR_TURBO_ACTIVATION_RATIO, &tar);
1313 	if (!err) {
1314 		int tar_levels;
1315 
1316 		/* Do some sanity checking for safety */
1317 		tar_levels = tar & 0xff;
1318 		if (tdp_ratio - 1 == tar_levels) {
1319 			max_pstate = tar_levels;
1320 			pr_debug("max_pstate=TAC %x\n", max_pstate);
1321 		}
1322 	}
1323 
1324 	return max_pstate;
1325 }
1326 
1327 static int core_get_turbo_pstate(void)
1328 {
1329 	u64 value;
1330 	int nont, ret;
1331 
1332 	rdmsrl(MSR_TURBO_RATIO_LIMIT, value);
1333 	nont = core_get_max_pstate();
1334 	ret = (value) & 255;
1335 	if (ret <= nont)
1336 		ret = nont;
1337 	return ret;
1338 }
1339 
1340 static inline int core_get_scaling(void)
1341 {
1342 	return 100000;
1343 }
1344 
1345 static u64 core_get_val(struct cpudata *cpudata, int pstate)
1346 {
1347 	u64 val;
1348 
1349 	val = (u64)pstate << 8;
1350 	if (global.no_turbo && !global.turbo_disabled)
1351 		val |= (u64)1 << 32;
1352 
1353 	return val;
1354 }
1355 
1356 static int knl_get_aperf_mperf_shift(void)
1357 {
1358 	return 10;
1359 }
1360 
1361 static int knl_get_turbo_pstate(void)
1362 {
1363 	u64 value;
1364 	int nont, ret;
1365 
1366 	rdmsrl(MSR_TURBO_RATIO_LIMIT, value);
1367 	nont = core_get_max_pstate();
1368 	ret = (((value) >> 8) & 0xFF);
1369 	if (ret <= nont)
1370 		ret = nont;
1371 	return ret;
1372 }
1373 
1374 static int intel_pstate_get_base_pstate(struct cpudata *cpu)
1375 {
1376 	return global.no_turbo || global.turbo_disabled ?
1377 			cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
1378 }
1379 
1380 static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate)
1381 {
1382 	trace_cpu_frequency(pstate * cpu->pstate.scaling, cpu->cpu);
1383 	cpu->pstate.current_pstate = pstate;
1384 	/*
1385 	 * Generally, there is no guarantee that this code will always run on
1386 	 * the CPU being updated, so force the register update to run on the
1387 	 * right CPU.
1388 	 */
1389 	wrmsrl_on_cpu(cpu->cpu, MSR_IA32_PERF_CTL,
1390 		      pstate_funcs.get_val(cpu, pstate));
1391 }
1392 
1393 static void intel_pstate_set_min_pstate(struct cpudata *cpu)
1394 {
1395 	intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate);
1396 }
1397 
1398 static void intel_pstate_max_within_limits(struct cpudata *cpu)
1399 {
1400 	int pstate;
1401 
1402 	update_turbo_state();
1403 	pstate = intel_pstate_get_base_pstate(cpu);
1404 	pstate = max(cpu->pstate.min_pstate, cpu->max_perf_ratio);
1405 	intel_pstate_set_pstate(cpu, pstate);
1406 }
1407 
1408 static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
1409 {
1410 	cpu->pstate.min_pstate = pstate_funcs.get_min();
1411 	cpu->pstate.max_pstate = pstate_funcs.get_max();
1412 	cpu->pstate.max_pstate_physical = pstate_funcs.get_max_physical();
1413 	cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
1414 	cpu->pstate.scaling = pstate_funcs.get_scaling();
1415 	cpu->pstate.max_freq = cpu->pstate.max_pstate * cpu->pstate.scaling;
1416 	cpu->pstate.turbo_freq = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
1417 
1418 	if (pstate_funcs.get_aperf_mperf_shift)
1419 		cpu->aperf_mperf_shift = pstate_funcs.get_aperf_mperf_shift();
1420 
1421 	if (pstate_funcs.get_vid)
1422 		pstate_funcs.get_vid(cpu);
1423 
1424 	intel_pstate_set_min_pstate(cpu);
1425 }
1426 
1427 /*
1428  * Long hold time will keep high perf limits for long time,
1429  * which negatively impacts perf/watt for some workloads,
1430  * like specpower. 3ms is based on experiements on some
1431  * workoads.
1432  */
1433 static int hwp_boost_hold_time_ns = 3 * NSEC_PER_MSEC;
1434 
1435 static inline void intel_pstate_hwp_boost_up(struct cpudata *cpu)
1436 {
1437 	u64 hwp_req = READ_ONCE(cpu->hwp_req_cached);
1438 	u32 max_limit = (hwp_req & 0xff00) >> 8;
1439 	u32 min_limit = (hwp_req & 0xff);
1440 	u32 boost_level1;
1441 
1442 	/*
1443 	 * Cases to consider (User changes via sysfs or boot time):
1444 	 * If, P0 (Turbo max) = P1 (Guaranteed max) = min:
1445 	 *	No boost, return.
1446 	 * If, P0 (Turbo max) > P1 (Guaranteed max) = min:
1447 	 *     Should result in one level boost only for P0.
1448 	 * If, P0 (Turbo max) = P1 (Guaranteed max) > min:
1449 	 *     Should result in two level boost:
1450 	 *         (min + p1)/2 and P1.
1451 	 * If, P0 (Turbo max) > P1 (Guaranteed max) > min:
1452 	 *     Should result in three level boost:
1453 	 *        (min + p1)/2, P1 and P0.
1454 	 */
1455 
1456 	/* If max and min are equal or already at max, nothing to boost */
1457 	if (max_limit == min_limit || cpu->hwp_boost_min >= max_limit)
1458 		return;
1459 
1460 	if (!cpu->hwp_boost_min)
1461 		cpu->hwp_boost_min = min_limit;
1462 
1463 	/* level at half way mark between min and guranteed */
1464 	boost_level1 = (HWP_GUARANTEED_PERF(cpu->hwp_cap_cached) + min_limit) >> 1;
1465 
1466 	if (cpu->hwp_boost_min < boost_level1)
1467 		cpu->hwp_boost_min = boost_level1;
1468 	else if (cpu->hwp_boost_min < HWP_GUARANTEED_PERF(cpu->hwp_cap_cached))
1469 		cpu->hwp_boost_min = HWP_GUARANTEED_PERF(cpu->hwp_cap_cached);
1470 	else if (cpu->hwp_boost_min == HWP_GUARANTEED_PERF(cpu->hwp_cap_cached) &&
1471 		 max_limit != HWP_GUARANTEED_PERF(cpu->hwp_cap_cached))
1472 		cpu->hwp_boost_min = max_limit;
1473 	else
1474 		return;
1475 
1476 	hwp_req = (hwp_req & ~GENMASK_ULL(7, 0)) | cpu->hwp_boost_min;
1477 	wrmsrl(MSR_HWP_REQUEST, hwp_req);
1478 	cpu->last_update = cpu->sample.time;
1479 }
1480 
1481 static inline void intel_pstate_hwp_boost_down(struct cpudata *cpu)
1482 {
1483 	if (cpu->hwp_boost_min) {
1484 		bool expired;
1485 
1486 		/* Check if we are idle for hold time to boost down */
1487 		expired = time_after64(cpu->sample.time, cpu->last_update +
1488 				       hwp_boost_hold_time_ns);
1489 		if (expired) {
1490 			wrmsrl(MSR_HWP_REQUEST, cpu->hwp_req_cached);
1491 			cpu->hwp_boost_min = 0;
1492 		}
1493 	}
1494 	cpu->last_update = cpu->sample.time;
1495 }
1496 
1497 static inline void intel_pstate_update_util_hwp_local(struct cpudata *cpu,
1498 						      u64 time)
1499 {
1500 	cpu->sample.time = time;
1501 
1502 	if (cpu->sched_flags & SCHED_CPUFREQ_IOWAIT) {
1503 		bool do_io = false;
1504 
1505 		cpu->sched_flags = 0;
1506 		/*
1507 		 * Set iowait_boost flag and update time. Since IO WAIT flag
1508 		 * is set all the time, we can't just conclude that there is
1509 		 * some IO bound activity is scheduled on this CPU with just
1510 		 * one occurrence. If we receive at least two in two
1511 		 * consecutive ticks, then we treat as boost candidate.
1512 		 */
1513 		if (time_before64(time, cpu->last_io_update + 2 * TICK_NSEC))
1514 			do_io = true;
1515 
1516 		cpu->last_io_update = time;
1517 
1518 		if (do_io)
1519 			intel_pstate_hwp_boost_up(cpu);
1520 
1521 	} else {
1522 		intel_pstate_hwp_boost_down(cpu);
1523 	}
1524 }
1525 
1526 static inline void intel_pstate_update_util_hwp(struct update_util_data *data,
1527 						u64 time, unsigned int flags)
1528 {
1529 	struct cpudata *cpu = container_of(data, struct cpudata, update_util);
1530 
1531 	cpu->sched_flags |= flags;
1532 
1533 	if (smp_processor_id() == cpu->cpu)
1534 		intel_pstate_update_util_hwp_local(cpu, time);
1535 }
1536 
1537 static inline void intel_pstate_calc_avg_perf(struct cpudata *cpu)
1538 {
1539 	struct sample *sample = &cpu->sample;
1540 
1541 	sample->core_avg_perf = div_ext_fp(sample->aperf, sample->mperf);
1542 }
1543 
1544 static inline bool intel_pstate_sample(struct cpudata *cpu, u64 time)
1545 {
1546 	u64 aperf, mperf;
1547 	unsigned long flags;
1548 	u64 tsc;
1549 
1550 	local_irq_save(flags);
1551 	rdmsrl(MSR_IA32_APERF, aperf);
1552 	rdmsrl(MSR_IA32_MPERF, mperf);
1553 	tsc = rdtsc();
1554 	if (cpu->prev_mperf == mperf || cpu->prev_tsc == tsc) {
1555 		local_irq_restore(flags);
1556 		return false;
1557 	}
1558 	local_irq_restore(flags);
1559 
1560 	cpu->last_sample_time = cpu->sample.time;
1561 	cpu->sample.time = time;
1562 	cpu->sample.aperf = aperf;
1563 	cpu->sample.mperf = mperf;
1564 	cpu->sample.tsc =  tsc;
1565 	cpu->sample.aperf -= cpu->prev_aperf;
1566 	cpu->sample.mperf -= cpu->prev_mperf;
1567 	cpu->sample.tsc -= cpu->prev_tsc;
1568 
1569 	cpu->prev_aperf = aperf;
1570 	cpu->prev_mperf = mperf;
1571 	cpu->prev_tsc = tsc;
1572 	/*
1573 	 * First time this function is invoked in a given cycle, all of the
1574 	 * previous sample data fields are equal to zero or stale and they must
1575 	 * be populated with meaningful numbers for things to work, so assume
1576 	 * that sample.time will always be reset before setting the utilization
1577 	 * update hook and make the caller skip the sample then.
1578 	 */
1579 	if (cpu->last_sample_time) {
1580 		intel_pstate_calc_avg_perf(cpu);
1581 		return true;
1582 	}
1583 	return false;
1584 }
1585 
1586 static inline int32_t get_avg_frequency(struct cpudata *cpu)
1587 {
1588 	return mul_ext_fp(cpu->sample.core_avg_perf, cpu_khz);
1589 }
1590 
1591 static inline int32_t get_avg_pstate(struct cpudata *cpu)
1592 {
1593 	return mul_ext_fp(cpu->pstate.max_pstate_physical,
1594 			  cpu->sample.core_avg_perf);
1595 }
1596 
1597 static inline int32_t get_target_pstate(struct cpudata *cpu)
1598 {
1599 	struct sample *sample = &cpu->sample;
1600 	int32_t busy_frac, boost;
1601 	int target, avg_pstate;
1602 
1603 	busy_frac = div_fp(sample->mperf << cpu->aperf_mperf_shift,
1604 			   sample->tsc);
1605 
1606 	boost = cpu->iowait_boost;
1607 	cpu->iowait_boost >>= 1;
1608 
1609 	if (busy_frac < boost)
1610 		busy_frac = boost;
1611 
1612 	sample->busy_scaled = busy_frac * 100;
1613 
1614 	target = global.no_turbo || global.turbo_disabled ?
1615 			cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
1616 	target += target >> 2;
1617 	target = mul_fp(target, busy_frac);
1618 	if (target < cpu->pstate.min_pstate)
1619 		target = cpu->pstate.min_pstate;
1620 
1621 	/*
1622 	 * If the average P-state during the previous cycle was higher than the
1623 	 * current target, add 50% of the difference to the target to reduce
1624 	 * possible performance oscillations and offset possible performance
1625 	 * loss related to moving the workload from one CPU to another within
1626 	 * a package/module.
1627 	 */
1628 	avg_pstate = get_avg_pstate(cpu);
1629 	if (avg_pstate > target)
1630 		target += (avg_pstate - target) >> 1;
1631 
1632 	return target;
1633 }
1634 
1635 static int intel_pstate_prepare_request(struct cpudata *cpu, int pstate)
1636 {
1637 	int max_pstate = intel_pstate_get_base_pstate(cpu);
1638 	int min_pstate;
1639 
1640 	min_pstate = max(cpu->pstate.min_pstate, cpu->min_perf_ratio);
1641 	max_pstate = max(min_pstate, cpu->max_perf_ratio);
1642 	return clamp_t(int, pstate, min_pstate, max_pstate);
1643 }
1644 
1645 static void intel_pstate_update_pstate(struct cpudata *cpu, int pstate)
1646 {
1647 	if (pstate == cpu->pstate.current_pstate)
1648 		return;
1649 
1650 	cpu->pstate.current_pstate = pstate;
1651 	wrmsrl(MSR_IA32_PERF_CTL, pstate_funcs.get_val(cpu, pstate));
1652 }
1653 
1654 static void intel_pstate_adjust_pstate(struct cpudata *cpu)
1655 {
1656 	int from = cpu->pstate.current_pstate;
1657 	struct sample *sample;
1658 	int target_pstate;
1659 
1660 	update_turbo_state();
1661 
1662 	target_pstate = get_target_pstate(cpu);
1663 	target_pstate = intel_pstate_prepare_request(cpu, target_pstate);
1664 	trace_cpu_frequency(target_pstate * cpu->pstate.scaling, cpu->cpu);
1665 	intel_pstate_update_pstate(cpu, target_pstate);
1666 
1667 	sample = &cpu->sample;
1668 	trace_pstate_sample(mul_ext_fp(100, sample->core_avg_perf),
1669 		fp_toint(sample->busy_scaled),
1670 		from,
1671 		cpu->pstate.current_pstate,
1672 		sample->mperf,
1673 		sample->aperf,
1674 		sample->tsc,
1675 		get_avg_frequency(cpu),
1676 		fp_toint(cpu->iowait_boost * 100));
1677 }
1678 
1679 static void intel_pstate_update_util(struct update_util_data *data, u64 time,
1680 				     unsigned int flags)
1681 {
1682 	struct cpudata *cpu = container_of(data, struct cpudata, update_util);
1683 	u64 delta_ns;
1684 
1685 	/* Don't allow remote callbacks */
1686 	if (smp_processor_id() != cpu->cpu)
1687 		return;
1688 
1689 	if (flags & SCHED_CPUFREQ_IOWAIT) {
1690 		cpu->iowait_boost = int_tofp(1);
1691 		cpu->last_update = time;
1692 		/*
1693 		 * The last time the busy was 100% so P-state was max anyway
1694 		 * so avoid overhead of computation.
1695 		 */
1696 		if (fp_toint(cpu->sample.busy_scaled) == 100)
1697 			return;
1698 
1699 		goto set_pstate;
1700 	} else if (cpu->iowait_boost) {
1701 		/* Clear iowait_boost if the CPU may have been idle. */
1702 		delta_ns = time - cpu->last_update;
1703 		if (delta_ns > TICK_NSEC)
1704 			cpu->iowait_boost = 0;
1705 	}
1706 	cpu->last_update = time;
1707 	delta_ns = time - cpu->sample.time;
1708 	if ((s64)delta_ns < INTEL_PSTATE_SAMPLING_INTERVAL)
1709 		return;
1710 
1711 set_pstate:
1712 	if (intel_pstate_sample(cpu, time))
1713 		intel_pstate_adjust_pstate(cpu);
1714 }
1715 
1716 static struct pstate_funcs core_funcs = {
1717 	.get_max = core_get_max_pstate,
1718 	.get_max_physical = core_get_max_pstate_physical,
1719 	.get_min = core_get_min_pstate,
1720 	.get_turbo = core_get_turbo_pstate,
1721 	.get_scaling = core_get_scaling,
1722 	.get_val = core_get_val,
1723 };
1724 
1725 static const struct pstate_funcs silvermont_funcs = {
1726 	.get_max = atom_get_max_pstate,
1727 	.get_max_physical = atom_get_max_pstate,
1728 	.get_min = atom_get_min_pstate,
1729 	.get_turbo = atom_get_turbo_pstate,
1730 	.get_val = atom_get_val,
1731 	.get_scaling = silvermont_get_scaling,
1732 	.get_vid = atom_get_vid,
1733 };
1734 
1735 static const struct pstate_funcs airmont_funcs = {
1736 	.get_max = atom_get_max_pstate,
1737 	.get_max_physical = atom_get_max_pstate,
1738 	.get_min = atom_get_min_pstate,
1739 	.get_turbo = atom_get_turbo_pstate,
1740 	.get_val = atom_get_val,
1741 	.get_scaling = airmont_get_scaling,
1742 	.get_vid = atom_get_vid,
1743 };
1744 
1745 static const struct pstate_funcs knl_funcs = {
1746 	.get_max = core_get_max_pstate,
1747 	.get_max_physical = core_get_max_pstate_physical,
1748 	.get_min = core_get_min_pstate,
1749 	.get_turbo = knl_get_turbo_pstate,
1750 	.get_aperf_mperf_shift = knl_get_aperf_mperf_shift,
1751 	.get_scaling = core_get_scaling,
1752 	.get_val = core_get_val,
1753 };
1754 
1755 #define ICPU(model, policy) \
1756 	{ X86_VENDOR_INTEL, 6, model, X86_FEATURE_APERFMPERF,\
1757 			(unsigned long)&policy }
1758 
1759 static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
1760 	ICPU(INTEL_FAM6_SANDYBRIDGE, 		core_funcs),
1761 	ICPU(INTEL_FAM6_SANDYBRIDGE_X,		core_funcs),
1762 	ICPU(INTEL_FAM6_ATOM_SILVERMONT1,	silvermont_funcs),
1763 	ICPU(INTEL_FAM6_IVYBRIDGE,		core_funcs),
1764 	ICPU(INTEL_FAM6_HASWELL_CORE,		core_funcs),
1765 	ICPU(INTEL_FAM6_BROADWELL_CORE,		core_funcs),
1766 	ICPU(INTEL_FAM6_IVYBRIDGE_X,		core_funcs),
1767 	ICPU(INTEL_FAM6_HASWELL_X,		core_funcs),
1768 	ICPU(INTEL_FAM6_HASWELL_ULT,		core_funcs),
1769 	ICPU(INTEL_FAM6_HASWELL_GT3E,		core_funcs),
1770 	ICPU(INTEL_FAM6_BROADWELL_GT3E,		core_funcs),
1771 	ICPU(INTEL_FAM6_ATOM_AIRMONT,		airmont_funcs),
1772 	ICPU(INTEL_FAM6_SKYLAKE_MOBILE,		core_funcs),
1773 	ICPU(INTEL_FAM6_BROADWELL_X,		core_funcs),
1774 	ICPU(INTEL_FAM6_SKYLAKE_DESKTOP,	core_funcs),
1775 	ICPU(INTEL_FAM6_BROADWELL_XEON_D,	core_funcs),
1776 	ICPU(INTEL_FAM6_XEON_PHI_KNL,		knl_funcs),
1777 	ICPU(INTEL_FAM6_XEON_PHI_KNM,		knl_funcs),
1778 	ICPU(INTEL_FAM6_ATOM_GOLDMONT,		core_funcs),
1779 	ICPU(INTEL_FAM6_ATOM_GEMINI_LAKE,       core_funcs),
1780 	ICPU(INTEL_FAM6_SKYLAKE_X,		core_funcs),
1781 	{}
1782 };
1783 MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
1784 
1785 static const struct x86_cpu_id intel_pstate_cpu_oob_ids[] __initconst = {
1786 	ICPU(INTEL_FAM6_BROADWELL_XEON_D, core_funcs),
1787 	ICPU(INTEL_FAM6_BROADWELL_X, core_funcs),
1788 	ICPU(INTEL_FAM6_SKYLAKE_X, core_funcs),
1789 	{}
1790 };
1791 
1792 static const struct x86_cpu_id intel_pstate_cpu_ee_disable_ids[] = {
1793 	ICPU(INTEL_FAM6_KABYLAKE_DESKTOP, core_funcs),
1794 	{}
1795 };
1796 
1797 static const struct x86_cpu_id intel_pstate_hwp_boost_ids[] = {
1798 	ICPU(INTEL_FAM6_SKYLAKE_X, core_funcs),
1799 	ICPU(INTEL_FAM6_SKYLAKE_DESKTOP, core_funcs),
1800 	{}
1801 };
1802 
1803 static int intel_pstate_init_cpu(unsigned int cpunum)
1804 {
1805 	struct cpudata *cpu;
1806 
1807 	cpu = all_cpu_data[cpunum];
1808 
1809 	if (!cpu) {
1810 		cpu = kzalloc(sizeof(*cpu), GFP_KERNEL);
1811 		if (!cpu)
1812 			return -ENOMEM;
1813 
1814 		all_cpu_data[cpunum] = cpu;
1815 
1816 		cpu->epp_default = -EINVAL;
1817 		cpu->epp_powersave = -EINVAL;
1818 		cpu->epp_saved = -EINVAL;
1819 	}
1820 
1821 	cpu = all_cpu_data[cpunum];
1822 
1823 	cpu->cpu = cpunum;
1824 
1825 	if (hwp_active) {
1826 		const struct x86_cpu_id *id;
1827 
1828 		id = x86_match_cpu(intel_pstate_cpu_ee_disable_ids);
1829 		if (id)
1830 			intel_pstate_disable_ee(cpunum);
1831 
1832 		intel_pstate_hwp_enable(cpu);
1833 
1834 		id = x86_match_cpu(intel_pstate_hwp_boost_ids);
1835 		if (id)
1836 			hwp_boost = true;
1837 	}
1838 
1839 	intel_pstate_get_cpu_pstates(cpu);
1840 
1841 	pr_debug("controlling: cpu %d\n", cpunum);
1842 
1843 	return 0;
1844 }
1845 
1846 static void intel_pstate_set_update_util_hook(unsigned int cpu_num)
1847 {
1848 	struct cpudata *cpu = all_cpu_data[cpu_num];
1849 
1850 	if (hwp_active && !hwp_boost)
1851 		return;
1852 
1853 	if (cpu->update_util_set)
1854 		return;
1855 
1856 	/* Prevent intel_pstate_update_util() from using stale data. */
1857 	cpu->sample.time = 0;
1858 	cpufreq_add_update_util_hook(cpu_num, &cpu->update_util,
1859 				     (hwp_active ?
1860 				      intel_pstate_update_util_hwp :
1861 				      intel_pstate_update_util));
1862 	cpu->update_util_set = true;
1863 }
1864 
1865 static void intel_pstate_clear_update_util_hook(unsigned int cpu)
1866 {
1867 	struct cpudata *cpu_data = all_cpu_data[cpu];
1868 
1869 	if (!cpu_data->update_util_set)
1870 		return;
1871 
1872 	cpufreq_remove_update_util_hook(cpu);
1873 	cpu_data->update_util_set = false;
1874 	synchronize_sched();
1875 }
1876 
1877 static int intel_pstate_get_max_freq(struct cpudata *cpu)
1878 {
1879 	return global.turbo_disabled || global.no_turbo ?
1880 			cpu->pstate.max_freq : cpu->pstate.turbo_freq;
1881 }
1882 
1883 static void intel_pstate_update_perf_limits(struct cpufreq_policy *policy,
1884 					    struct cpudata *cpu)
1885 {
1886 	int max_freq = intel_pstate_get_max_freq(cpu);
1887 	int32_t max_policy_perf, min_policy_perf;
1888 	int max_state, turbo_max;
1889 
1890 	/*
1891 	 * HWP needs some special consideration, because on BDX the
1892 	 * HWP_REQUEST uses abstract value to represent performance
1893 	 * rather than pure ratios.
1894 	 */
1895 	if (hwp_active) {
1896 		intel_pstate_get_hwp_max(cpu->cpu, &turbo_max, &max_state);
1897 	} else {
1898 		max_state = intel_pstate_get_base_pstate(cpu);
1899 		turbo_max = cpu->pstate.turbo_pstate;
1900 	}
1901 
1902 	max_policy_perf = max_state * policy->max / max_freq;
1903 	if (policy->max == policy->min) {
1904 		min_policy_perf = max_policy_perf;
1905 	} else {
1906 		min_policy_perf = max_state * policy->min / max_freq;
1907 		min_policy_perf = clamp_t(int32_t, min_policy_perf,
1908 					  0, max_policy_perf);
1909 	}
1910 
1911 	pr_debug("cpu:%d max_state %d min_policy_perf:%d max_policy_perf:%d\n",
1912 		 policy->cpu, max_state,
1913 		 min_policy_perf, max_policy_perf);
1914 
1915 	/* Normalize user input to [min_perf, max_perf] */
1916 	if (per_cpu_limits) {
1917 		cpu->min_perf_ratio = min_policy_perf;
1918 		cpu->max_perf_ratio = max_policy_perf;
1919 	} else {
1920 		int32_t global_min, global_max;
1921 
1922 		/* Global limits are in percent of the maximum turbo P-state. */
1923 		global_max = DIV_ROUND_UP(turbo_max * global.max_perf_pct, 100);
1924 		global_min = DIV_ROUND_UP(turbo_max * global.min_perf_pct, 100);
1925 		global_min = clamp_t(int32_t, global_min, 0, global_max);
1926 
1927 		pr_debug("cpu:%d global_min:%d global_max:%d\n", policy->cpu,
1928 			 global_min, global_max);
1929 
1930 		cpu->min_perf_ratio = max(min_policy_perf, global_min);
1931 		cpu->min_perf_ratio = min(cpu->min_perf_ratio, max_policy_perf);
1932 		cpu->max_perf_ratio = min(max_policy_perf, global_max);
1933 		cpu->max_perf_ratio = max(min_policy_perf, cpu->max_perf_ratio);
1934 
1935 		/* Make sure min_perf <= max_perf */
1936 		cpu->min_perf_ratio = min(cpu->min_perf_ratio,
1937 					  cpu->max_perf_ratio);
1938 
1939 	}
1940 	pr_debug("cpu:%d max_perf_ratio:%d min_perf_ratio:%d\n", policy->cpu,
1941 		 cpu->max_perf_ratio,
1942 		 cpu->min_perf_ratio);
1943 }
1944 
1945 static int intel_pstate_set_policy(struct cpufreq_policy *policy)
1946 {
1947 	struct cpudata *cpu;
1948 
1949 	if (!policy->cpuinfo.max_freq)
1950 		return -ENODEV;
1951 
1952 	pr_debug("set_policy cpuinfo.max %u policy->max %u\n",
1953 		 policy->cpuinfo.max_freq, policy->max);
1954 
1955 	cpu = all_cpu_data[policy->cpu];
1956 	cpu->policy = policy->policy;
1957 
1958 	mutex_lock(&intel_pstate_limits_lock);
1959 
1960 	intel_pstate_update_perf_limits(policy, cpu);
1961 
1962 	if (cpu->policy == CPUFREQ_POLICY_PERFORMANCE) {
1963 		/*
1964 		 * NOHZ_FULL CPUs need this as the governor callback may not
1965 		 * be invoked on them.
1966 		 */
1967 		intel_pstate_clear_update_util_hook(policy->cpu);
1968 		intel_pstate_max_within_limits(cpu);
1969 	} else {
1970 		intel_pstate_set_update_util_hook(policy->cpu);
1971 	}
1972 
1973 	if (hwp_active) {
1974 		/*
1975 		 * When hwp_boost was active before and dynamically it
1976 		 * was turned off, in that case we need to clear the
1977 		 * update util hook.
1978 		 */
1979 		if (!hwp_boost)
1980 			intel_pstate_clear_update_util_hook(policy->cpu);
1981 		intel_pstate_hwp_set(policy->cpu);
1982 	}
1983 
1984 	mutex_unlock(&intel_pstate_limits_lock);
1985 
1986 	return 0;
1987 }
1988 
1989 static void intel_pstate_adjust_policy_max(struct cpufreq_policy *policy,
1990 					 struct cpudata *cpu)
1991 {
1992 	if (cpu->pstate.max_pstate_physical > cpu->pstate.max_pstate &&
1993 	    policy->max < policy->cpuinfo.max_freq &&
1994 	    policy->max > cpu->pstate.max_freq) {
1995 		pr_debug("policy->max > max non turbo frequency\n");
1996 		policy->max = policy->cpuinfo.max_freq;
1997 	}
1998 }
1999 
2000 static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
2001 {
2002 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2003 
2004 	update_turbo_state();
2005 	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
2006 				     intel_pstate_get_max_freq(cpu));
2007 
2008 	if (policy->policy != CPUFREQ_POLICY_POWERSAVE &&
2009 	    policy->policy != CPUFREQ_POLICY_PERFORMANCE)
2010 		return -EINVAL;
2011 
2012 	intel_pstate_adjust_policy_max(policy, cpu);
2013 
2014 	return 0;
2015 }
2016 
2017 static void intel_cpufreq_stop_cpu(struct cpufreq_policy *policy)
2018 {
2019 	intel_pstate_set_min_pstate(all_cpu_data[policy->cpu]);
2020 }
2021 
2022 static void intel_pstate_stop_cpu(struct cpufreq_policy *policy)
2023 {
2024 	pr_debug("CPU %d exiting\n", policy->cpu);
2025 
2026 	intel_pstate_clear_update_util_hook(policy->cpu);
2027 	if (hwp_active)
2028 		intel_pstate_hwp_save_state(policy);
2029 	else
2030 		intel_cpufreq_stop_cpu(policy);
2031 }
2032 
2033 static int intel_pstate_cpu_exit(struct cpufreq_policy *policy)
2034 {
2035 	intel_pstate_exit_perf_limits(policy);
2036 
2037 	policy->fast_switch_possible = false;
2038 
2039 	return 0;
2040 }
2041 
2042 static int __intel_pstate_cpu_init(struct cpufreq_policy *policy)
2043 {
2044 	struct cpudata *cpu;
2045 	int rc;
2046 
2047 	rc = intel_pstate_init_cpu(policy->cpu);
2048 	if (rc)
2049 		return rc;
2050 
2051 	cpu = all_cpu_data[policy->cpu];
2052 
2053 	cpu->max_perf_ratio = 0xFF;
2054 	cpu->min_perf_ratio = 0;
2055 
2056 	policy->min = cpu->pstate.min_pstate * cpu->pstate.scaling;
2057 	policy->max = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
2058 
2059 	/* cpuinfo and default policy values */
2060 	policy->cpuinfo.min_freq = cpu->pstate.min_pstate * cpu->pstate.scaling;
2061 	update_turbo_state();
2062 	policy->cpuinfo.max_freq = global.turbo_disabled ?
2063 			cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
2064 	policy->cpuinfo.max_freq *= cpu->pstate.scaling;
2065 
2066 	intel_pstate_init_acpi_perf_limits(policy);
2067 
2068 	policy->fast_switch_possible = true;
2069 
2070 	return 0;
2071 }
2072 
2073 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
2074 {
2075 	int ret = __intel_pstate_cpu_init(policy);
2076 
2077 	if (ret)
2078 		return ret;
2079 
2080 	if (IS_ENABLED(CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE))
2081 		policy->policy = CPUFREQ_POLICY_PERFORMANCE;
2082 	else
2083 		policy->policy = CPUFREQ_POLICY_POWERSAVE;
2084 
2085 	return 0;
2086 }
2087 
2088 static struct cpufreq_driver intel_pstate = {
2089 	.flags		= CPUFREQ_CONST_LOOPS,
2090 	.verify		= intel_pstate_verify_policy,
2091 	.setpolicy	= intel_pstate_set_policy,
2092 	.suspend	= intel_pstate_hwp_save_state,
2093 	.resume		= intel_pstate_resume,
2094 	.init		= intel_pstate_cpu_init,
2095 	.exit		= intel_pstate_cpu_exit,
2096 	.stop_cpu	= intel_pstate_stop_cpu,
2097 	.name		= "intel_pstate",
2098 };
2099 
2100 static int intel_cpufreq_verify_policy(struct cpufreq_policy *policy)
2101 {
2102 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2103 
2104 	update_turbo_state();
2105 	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
2106 				     intel_pstate_get_max_freq(cpu));
2107 
2108 	intel_pstate_adjust_policy_max(policy, cpu);
2109 
2110 	intel_pstate_update_perf_limits(policy, cpu);
2111 
2112 	return 0;
2113 }
2114 
2115 /* Use of trace in passive mode:
2116  *
2117  * In passive mode the trace core_busy field (also known as the
2118  * performance field, and lablelled as such on the graphs; also known as
2119  * core_avg_perf) is not needed and so is re-assigned to indicate if the
2120  * driver call was via the normal or fast switch path. Various graphs
2121  * output from the intel_pstate_tracer.py utility that include core_busy
2122  * (or performance or core_avg_perf) have a fixed y-axis from 0 to 100%,
2123  * so we use 10 to indicate the the normal path through the driver, and
2124  * 90 to indicate the fast switch path through the driver.
2125  * The scaled_busy field is not used, and is set to 0.
2126  */
2127 
2128 #define	INTEL_PSTATE_TRACE_TARGET 10
2129 #define	INTEL_PSTATE_TRACE_FAST_SWITCH 90
2130 
2131 static void intel_cpufreq_trace(struct cpudata *cpu, unsigned int trace_type, int old_pstate)
2132 {
2133 	struct sample *sample;
2134 
2135 	if (!trace_pstate_sample_enabled())
2136 		return;
2137 
2138 	if (!intel_pstate_sample(cpu, ktime_get()))
2139 		return;
2140 
2141 	sample = &cpu->sample;
2142 	trace_pstate_sample(trace_type,
2143 		0,
2144 		old_pstate,
2145 		cpu->pstate.current_pstate,
2146 		sample->mperf,
2147 		sample->aperf,
2148 		sample->tsc,
2149 		get_avg_frequency(cpu),
2150 		fp_toint(cpu->iowait_boost * 100));
2151 }
2152 
2153 static int intel_cpufreq_target(struct cpufreq_policy *policy,
2154 				unsigned int target_freq,
2155 				unsigned int relation)
2156 {
2157 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2158 	struct cpufreq_freqs freqs;
2159 	int target_pstate, old_pstate;
2160 
2161 	update_turbo_state();
2162 
2163 	freqs.old = policy->cur;
2164 	freqs.new = target_freq;
2165 
2166 	cpufreq_freq_transition_begin(policy, &freqs);
2167 	switch (relation) {
2168 	case CPUFREQ_RELATION_L:
2169 		target_pstate = DIV_ROUND_UP(freqs.new, cpu->pstate.scaling);
2170 		break;
2171 	case CPUFREQ_RELATION_H:
2172 		target_pstate = freqs.new / cpu->pstate.scaling;
2173 		break;
2174 	default:
2175 		target_pstate = DIV_ROUND_CLOSEST(freqs.new, cpu->pstate.scaling);
2176 		break;
2177 	}
2178 	target_pstate = intel_pstate_prepare_request(cpu, target_pstate);
2179 	old_pstate = cpu->pstate.current_pstate;
2180 	if (target_pstate != cpu->pstate.current_pstate) {
2181 		cpu->pstate.current_pstate = target_pstate;
2182 		wrmsrl_on_cpu(policy->cpu, MSR_IA32_PERF_CTL,
2183 			      pstate_funcs.get_val(cpu, target_pstate));
2184 	}
2185 	freqs.new = target_pstate * cpu->pstate.scaling;
2186 	intel_cpufreq_trace(cpu, INTEL_PSTATE_TRACE_TARGET, old_pstate);
2187 	cpufreq_freq_transition_end(policy, &freqs, false);
2188 
2189 	return 0;
2190 }
2191 
2192 static unsigned int intel_cpufreq_fast_switch(struct cpufreq_policy *policy,
2193 					      unsigned int target_freq)
2194 {
2195 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2196 	int target_pstate, old_pstate;
2197 
2198 	update_turbo_state();
2199 
2200 	target_pstate = DIV_ROUND_UP(target_freq, cpu->pstate.scaling);
2201 	target_pstate = intel_pstate_prepare_request(cpu, target_pstate);
2202 	old_pstate = cpu->pstate.current_pstate;
2203 	intel_pstate_update_pstate(cpu, target_pstate);
2204 	intel_cpufreq_trace(cpu, INTEL_PSTATE_TRACE_FAST_SWITCH, old_pstate);
2205 	return target_pstate * cpu->pstate.scaling;
2206 }
2207 
2208 static int intel_cpufreq_cpu_init(struct cpufreq_policy *policy)
2209 {
2210 	int ret = __intel_pstate_cpu_init(policy);
2211 
2212 	if (ret)
2213 		return ret;
2214 
2215 	policy->cpuinfo.transition_latency = INTEL_CPUFREQ_TRANSITION_LATENCY;
2216 	policy->transition_delay_us = INTEL_CPUFREQ_TRANSITION_DELAY;
2217 	/* This reflects the intel_pstate_get_cpu_pstates() setting. */
2218 	policy->cur = policy->cpuinfo.min_freq;
2219 
2220 	return 0;
2221 }
2222 
2223 static struct cpufreq_driver intel_cpufreq = {
2224 	.flags		= CPUFREQ_CONST_LOOPS,
2225 	.verify		= intel_cpufreq_verify_policy,
2226 	.target		= intel_cpufreq_target,
2227 	.fast_switch	= intel_cpufreq_fast_switch,
2228 	.init		= intel_cpufreq_cpu_init,
2229 	.exit		= intel_pstate_cpu_exit,
2230 	.stop_cpu	= intel_cpufreq_stop_cpu,
2231 	.name		= "intel_cpufreq",
2232 };
2233 
2234 static struct cpufreq_driver *default_driver = &intel_pstate;
2235 
2236 static void intel_pstate_driver_cleanup(void)
2237 {
2238 	unsigned int cpu;
2239 
2240 	get_online_cpus();
2241 	for_each_online_cpu(cpu) {
2242 		if (all_cpu_data[cpu]) {
2243 			if (intel_pstate_driver == &intel_pstate)
2244 				intel_pstate_clear_update_util_hook(cpu);
2245 
2246 			kfree(all_cpu_data[cpu]);
2247 			all_cpu_data[cpu] = NULL;
2248 		}
2249 	}
2250 	put_online_cpus();
2251 	intel_pstate_driver = NULL;
2252 }
2253 
2254 static int intel_pstate_register_driver(struct cpufreq_driver *driver)
2255 {
2256 	int ret;
2257 
2258 	memset(&global, 0, sizeof(global));
2259 	global.max_perf_pct = 100;
2260 
2261 	intel_pstate_driver = driver;
2262 	ret = cpufreq_register_driver(intel_pstate_driver);
2263 	if (ret) {
2264 		intel_pstate_driver_cleanup();
2265 		return ret;
2266 	}
2267 
2268 	global.min_perf_pct = min_perf_pct_min();
2269 
2270 	return 0;
2271 }
2272 
2273 static int intel_pstate_unregister_driver(void)
2274 {
2275 	if (hwp_active)
2276 		return -EBUSY;
2277 
2278 	cpufreq_unregister_driver(intel_pstate_driver);
2279 	intel_pstate_driver_cleanup();
2280 
2281 	return 0;
2282 }
2283 
2284 static ssize_t intel_pstate_show_status(char *buf)
2285 {
2286 	if (!intel_pstate_driver)
2287 		return sprintf(buf, "off\n");
2288 
2289 	return sprintf(buf, "%s\n", intel_pstate_driver == &intel_pstate ?
2290 					"active" : "passive");
2291 }
2292 
2293 static int intel_pstate_update_status(const char *buf, size_t size)
2294 {
2295 	int ret;
2296 
2297 	if (size == 3 && !strncmp(buf, "off", size))
2298 		return intel_pstate_driver ?
2299 			intel_pstate_unregister_driver() : -EINVAL;
2300 
2301 	if (size == 6 && !strncmp(buf, "active", size)) {
2302 		if (intel_pstate_driver) {
2303 			if (intel_pstate_driver == &intel_pstate)
2304 				return 0;
2305 
2306 			ret = intel_pstate_unregister_driver();
2307 			if (ret)
2308 				return ret;
2309 		}
2310 
2311 		return intel_pstate_register_driver(&intel_pstate);
2312 	}
2313 
2314 	if (size == 7 && !strncmp(buf, "passive", size)) {
2315 		if (intel_pstate_driver) {
2316 			if (intel_pstate_driver == &intel_cpufreq)
2317 				return 0;
2318 
2319 			ret = intel_pstate_unregister_driver();
2320 			if (ret)
2321 				return ret;
2322 		}
2323 
2324 		return intel_pstate_register_driver(&intel_cpufreq);
2325 	}
2326 
2327 	return -EINVAL;
2328 }
2329 
2330 static int no_load __initdata;
2331 static int no_hwp __initdata;
2332 static int hwp_only __initdata;
2333 static unsigned int force_load __initdata;
2334 
2335 static int __init intel_pstate_msrs_not_valid(void)
2336 {
2337 	if (!pstate_funcs.get_max() ||
2338 	    !pstate_funcs.get_min() ||
2339 	    !pstate_funcs.get_turbo())
2340 		return -ENODEV;
2341 
2342 	return 0;
2343 }
2344 
2345 static void __init copy_cpu_funcs(struct pstate_funcs *funcs)
2346 {
2347 	pstate_funcs.get_max   = funcs->get_max;
2348 	pstate_funcs.get_max_physical = funcs->get_max_physical;
2349 	pstate_funcs.get_min   = funcs->get_min;
2350 	pstate_funcs.get_turbo = funcs->get_turbo;
2351 	pstate_funcs.get_scaling = funcs->get_scaling;
2352 	pstate_funcs.get_val   = funcs->get_val;
2353 	pstate_funcs.get_vid   = funcs->get_vid;
2354 	pstate_funcs.get_aperf_mperf_shift = funcs->get_aperf_mperf_shift;
2355 }
2356 
2357 #ifdef CONFIG_ACPI
2358 
2359 static bool __init intel_pstate_no_acpi_pss(void)
2360 {
2361 	int i;
2362 
2363 	for_each_possible_cpu(i) {
2364 		acpi_status status;
2365 		union acpi_object *pss;
2366 		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
2367 		struct acpi_processor *pr = per_cpu(processors, i);
2368 
2369 		if (!pr)
2370 			continue;
2371 
2372 		status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
2373 		if (ACPI_FAILURE(status))
2374 			continue;
2375 
2376 		pss = buffer.pointer;
2377 		if (pss && pss->type == ACPI_TYPE_PACKAGE) {
2378 			kfree(pss);
2379 			return false;
2380 		}
2381 
2382 		kfree(pss);
2383 	}
2384 
2385 	return true;
2386 }
2387 
2388 static bool __init intel_pstate_has_acpi_ppc(void)
2389 {
2390 	int i;
2391 
2392 	for_each_possible_cpu(i) {
2393 		struct acpi_processor *pr = per_cpu(processors, i);
2394 
2395 		if (!pr)
2396 			continue;
2397 		if (acpi_has_method(pr->handle, "_PPC"))
2398 			return true;
2399 	}
2400 	return false;
2401 }
2402 
2403 enum {
2404 	PSS,
2405 	PPC,
2406 };
2407 
2408 /* Hardware vendor-specific info that has its own power management modes */
2409 static struct acpi_platform_list plat_info[] __initdata = {
2410 	{"HP    ", "ProLiant", 0, ACPI_SIG_FADT, all_versions, 0, PSS},
2411 	{"ORACLE", "X4-2    ", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2412 	{"ORACLE", "X4-2L   ", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2413 	{"ORACLE", "X4-2B   ", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2414 	{"ORACLE", "X3-2    ", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2415 	{"ORACLE", "X3-2L   ", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2416 	{"ORACLE", "X3-2B   ", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2417 	{"ORACLE", "X4470M2 ", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2418 	{"ORACLE", "X4270M3 ", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2419 	{"ORACLE", "X4270M2 ", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2420 	{"ORACLE", "X4170M2 ", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2421 	{"ORACLE", "X4170 M3", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2422 	{"ORACLE", "X4275 M3", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2423 	{"ORACLE", "X6-2    ", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2424 	{"ORACLE", "Sudbury ", 0, ACPI_SIG_FADT, all_versions, 0, PPC},
2425 	{ } /* End */
2426 };
2427 
2428 static bool __init intel_pstate_platform_pwr_mgmt_exists(void)
2429 {
2430 	const struct x86_cpu_id *id;
2431 	u64 misc_pwr;
2432 	int idx;
2433 
2434 	id = x86_match_cpu(intel_pstate_cpu_oob_ids);
2435 	if (id) {
2436 		rdmsrl(MSR_MISC_PWR_MGMT, misc_pwr);
2437 		if ( misc_pwr & (1 << 8))
2438 			return true;
2439 	}
2440 
2441 	idx = acpi_match_platform_list(plat_info);
2442 	if (idx < 0)
2443 		return false;
2444 
2445 	switch (plat_info[idx].data) {
2446 	case PSS:
2447 		return intel_pstate_no_acpi_pss();
2448 	case PPC:
2449 		return intel_pstate_has_acpi_ppc() && !force_load;
2450 	}
2451 
2452 	return false;
2453 }
2454 
2455 static void intel_pstate_request_control_from_smm(void)
2456 {
2457 	/*
2458 	 * It may be unsafe to request P-states control from SMM if _PPC support
2459 	 * has not been enabled.
2460 	 */
2461 	if (acpi_ppc)
2462 		acpi_processor_pstate_control();
2463 }
2464 #else /* CONFIG_ACPI not enabled */
2465 static inline bool intel_pstate_platform_pwr_mgmt_exists(void) { return false; }
2466 static inline bool intel_pstate_has_acpi_ppc(void) { return false; }
2467 static inline void intel_pstate_request_control_from_smm(void) {}
2468 #endif /* CONFIG_ACPI */
2469 
2470 static const struct x86_cpu_id hwp_support_ids[] __initconst = {
2471 	{ X86_VENDOR_INTEL, 6, X86_MODEL_ANY, X86_FEATURE_HWP },
2472 	{}
2473 };
2474 
2475 static int __init intel_pstate_init(void)
2476 {
2477 	int rc;
2478 
2479 	if (no_load)
2480 		return -ENODEV;
2481 
2482 	if (x86_match_cpu(hwp_support_ids)) {
2483 		copy_cpu_funcs(&core_funcs);
2484 		if (!no_hwp) {
2485 			hwp_active++;
2486 			intel_pstate.attr = hwp_cpufreq_attrs;
2487 			goto hwp_cpu_matched;
2488 		}
2489 	} else {
2490 		const struct x86_cpu_id *id;
2491 
2492 		id = x86_match_cpu(intel_pstate_cpu_ids);
2493 		if (!id)
2494 			return -ENODEV;
2495 
2496 		copy_cpu_funcs((struct pstate_funcs *)id->driver_data);
2497 	}
2498 
2499 	if (intel_pstate_msrs_not_valid())
2500 		return -ENODEV;
2501 
2502 hwp_cpu_matched:
2503 	/*
2504 	 * The Intel pstate driver will be ignored if the platform
2505 	 * firmware has its own power management modes.
2506 	 */
2507 	if (intel_pstate_platform_pwr_mgmt_exists())
2508 		return -ENODEV;
2509 
2510 	if (!hwp_active && hwp_only)
2511 		return -ENOTSUPP;
2512 
2513 	pr_info("Intel P-state driver initializing\n");
2514 
2515 	all_cpu_data = vzalloc(array_size(sizeof(void *), num_possible_cpus()));
2516 	if (!all_cpu_data)
2517 		return -ENOMEM;
2518 
2519 	intel_pstate_request_control_from_smm();
2520 
2521 	intel_pstate_sysfs_expose_params();
2522 
2523 	mutex_lock(&intel_pstate_driver_lock);
2524 	rc = intel_pstate_register_driver(default_driver);
2525 	mutex_unlock(&intel_pstate_driver_lock);
2526 	if (rc)
2527 		return rc;
2528 
2529 	if (hwp_active)
2530 		pr_info("HWP enabled\n");
2531 
2532 	return 0;
2533 }
2534 device_initcall(intel_pstate_init);
2535 
2536 static int __init intel_pstate_setup(char *str)
2537 {
2538 	if (!str)
2539 		return -EINVAL;
2540 
2541 	if (!strcmp(str, "disable")) {
2542 		no_load = 1;
2543 	} else if (!strcmp(str, "passive")) {
2544 		pr_info("Passive mode enabled\n");
2545 		default_driver = &intel_cpufreq;
2546 		no_hwp = 1;
2547 	}
2548 	if (!strcmp(str, "no_hwp")) {
2549 		pr_info("HWP disabled\n");
2550 		no_hwp = 1;
2551 	}
2552 	if (!strcmp(str, "force"))
2553 		force_load = 1;
2554 	if (!strcmp(str, "hwp_only"))
2555 		hwp_only = 1;
2556 	if (!strcmp(str, "per_cpu_perf_limits"))
2557 		per_cpu_limits = true;
2558 
2559 #ifdef CONFIG_ACPI
2560 	if (!strcmp(str, "support_acpi_ppc"))
2561 		acpi_ppc = true;
2562 #endif
2563 
2564 	return 0;
2565 }
2566 early_param("intel_pstate", intel_pstate_setup);
2567 
2568 MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>");
2569 MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors");
2570 MODULE_LICENSE("GPL");
2571