xref: /linux/drivers/cpufreq/intel_pstate.c (revision 69fb09f6ccdb2f070557fd1f4c56c4d646694c8e)
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/debugfs.h>
30 #include <linux/acpi.h>
31 #include <linux/vmalloc.h>
32 #include <trace/events/power.h>
33 
34 #include <asm/div64.h>
35 #include <asm/msr.h>
36 #include <asm/cpu_device_id.h>
37 #include <asm/cpufeature.h>
38 #include <asm/intel-family.h>
39 
40 #define INTEL_PSTATE_DEFAULT_SAMPLING_INTERVAL	(10 * NSEC_PER_MSEC)
41 #define INTEL_PSTATE_HWP_SAMPLING_INTERVAL	(50 * NSEC_PER_MSEC)
42 
43 #define INTEL_CPUFREQ_TRANSITION_LATENCY	20000
44 #define INTEL_CPUFREQ_TRANSITION_DELAY		500
45 
46 #ifdef CONFIG_ACPI
47 #include <acpi/processor.h>
48 #include <acpi/cppc_acpi.h>
49 #endif
50 
51 #define FRAC_BITS 8
52 #define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
53 #define fp_toint(X) ((X) >> FRAC_BITS)
54 
55 #define EXT_BITS 6
56 #define EXT_FRAC_BITS (EXT_BITS + FRAC_BITS)
57 #define fp_ext_toint(X) ((X) >> EXT_FRAC_BITS)
58 #define int_ext_tofp(X) ((int64_t)(X) << EXT_FRAC_BITS)
59 
60 static inline int32_t mul_fp(int32_t x, int32_t y)
61 {
62 	return ((int64_t)x * (int64_t)y) >> FRAC_BITS;
63 }
64 
65 static inline int32_t div_fp(s64 x, s64 y)
66 {
67 	return div64_s64((int64_t)x << FRAC_BITS, y);
68 }
69 
70 static inline int ceiling_fp(int32_t x)
71 {
72 	int mask, ret;
73 
74 	ret = fp_toint(x);
75 	mask = (1 << FRAC_BITS) - 1;
76 	if (x & mask)
77 		ret += 1;
78 	return ret;
79 }
80 
81 static inline int32_t percent_fp(int percent)
82 {
83 	return div_fp(percent, 100);
84 }
85 
86 static inline u64 mul_ext_fp(u64 x, u64 y)
87 {
88 	return (x * y) >> EXT_FRAC_BITS;
89 }
90 
91 static inline u64 div_ext_fp(u64 x, u64 y)
92 {
93 	return div64_u64(x << EXT_FRAC_BITS, y);
94 }
95 
96 static inline int32_t percent_ext_fp(int percent)
97 {
98 	return div_ext_fp(percent, 100);
99 }
100 
101 /**
102  * struct sample -	Store performance sample
103  * @core_avg_perf:	Ratio of APERF/MPERF which is the actual average
104  *			performance during last sample period
105  * @busy_scaled:	Scaled busy value which is used to calculate next
106  *			P state. This can be different than core_avg_perf
107  *			to account for cpu idle period
108  * @aperf:		Difference of actual performance frequency clock count
109  *			read from APERF MSR between last and current sample
110  * @mperf:		Difference of maximum performance frequency clock count
111  *			read from MPERF MSR between last and current sample
112  * @tsc:		Difference of time stamp counter between last and
113  *			current sample
114  * @time:		Current time from scheduler
115  *
116  * This structure is used in the cpudata structure to store performance sample
117  * data for choosing next P State.
118  */
119 struct sample {
120 	int32_t core_avg_perf;
121 	int32_t busy_scaled;
122 	u64 aperf;
123 	u64 mperf;
124 	u64 tsc;
125 	u64 time;
126 };
127 
128 /**
129  * struct pstate_data - Store P state data
130  * @current_pstate:	Current requested P state
131  * @min_pstate:		Min P state possible for this platform
132  * @max_pstate:		Max P state possible for this platform
133  * @max_pstate_physical:This is physical Max P state for a processor
134  *			This can be higher than the max_pstate which can
135  *			be limited by platform thermal design power limits
136  * @scaling:		Scaling factor to  convert frequency to cpufreq
137  *			frequency units
138  * @turbo_pstate:	Max Turbo P state possible for this platform
139  * @max_freq:		@max_pstate frequency in cpufreq units
140  * @turbo_freq:		@turbo_pstate frequency in cpufreq units
141  *
142  * Stores the per cpu model P state limits and current P state.
143  */
144 struct pstate_data {
145 	int	current_pstate;
146 	int	min_pstate;
147 	int	max_pstate;
148 	int	max_pstate_physical;
149 	int	scaling;
150 	int	turbo_pstate;
151 	unsigned int max_freq;
152 	unsigned int turbo_freq;
153 };
154 
155 /**
156  * struct vid_data -	Stores voltage information data
157  * @min:		VID data for this platform corresponding to
158  *			the lowest P state
159  * @max:		VID data corresponding to the highest P State.
160  * @turbo:		VID data for turbo P state
161  * @ratio:		Ratio of (vid max - vid min) /
162  *			(max P state - Min P State)
163  *
164  * Stores the voltage data for DVFS (Dynamic Voltage and Frequency Scaling)
165  * This data is used in Atom platforms, where in addition to target P state,
166  * the voltage data needs to be specified to select next P State.
167  */
168 struct vid_data {
169 	int min;
170 	int max;
171 	int turbo;
172 	int32_t ratio;
173 };
174 
175 /**
176  * struct _pid -	Stores PID data
177  * @setpoint:		Target set point for busyness or performance
178  * @integral:		Storage for accumulated error values
179  * @p_gain:		PID proportional gain
180  * @i_gain:		PID integral gain
181  * @d_gain:		PID derivative gain
182  * @deadband:		PID deadband
183  * @last_err:		Last error storage for integral part of PID calculation
184  *
185  * Stores PID coefficients and last error for PID controller.
186  */
187 struct _pid {
188 	int setpoint;
189 	int32_t integral;
190 	int32_t p_gain;
191 	int32_t i_gain;
192 	int32_t d_gain;
193 	int deadband;
194 	int32_t last_err;
195 };
196 
197 /**
198  * struct global_params - Global parameters, mostly tunable via sysfs.
199  * @no_turbo:		Whether or not to use turbo P-states.
200  * @turbo_disabled:	Whethet or not turbo P-states are available at all,
201  *			based on the MSR_IA32_MISC_ENABLE value and whether or
202  *			not the maximum reported turbo P-state is different from
203  *			the maximum reported non-turbo one.
204  * @min_perf_pct:	Minimum capacity limit in percent of the maximum turbo
205  *			P-state capacity.
206  * @max_perf_pct:	Maximum capacity limit in percent of the maximum turbo
207  *			P-state capacity.
208  */
209 struct global_params {
210 	bool no_turbo;
211 	bool turbo_disabled;
212 	int max_perf_pct;
213 	int min_perf_pct;
214 };
215 
216 /**
217  * struct cpudata -	Per CPU instance data storage
218  * @cpu:		CPU number for this instance data
219  * @policy:		CPUFreq policy value
220  * @update_util:	CPUFreq utility callback information
221  * @update_util_set:	CPUFreq utility callback is set
222  * @iowait_boost:	iowait-related boost fraction
223  * @last_update:	Time of the last update.
224  * @pstate:		Stores P state limits for this CPU
225  * @vid:		Stores VID limits for this CPU
226  * @pid:		Stores PID parameters for this CPU
227  * @last_sample_time:	Last Sample time
228  * @prev_aperf:		Last APERF value read from APERF MSR
229  * @prev_mperf:		Last MPERF value read from MPERF MSR
230  * @prev_tsc:		Last timestamp counter (TSC) value
231  * @prev_cummulative_iowait: IO Wait time difference from last and
232  *			current sample
233  * @sample:		Storage for storing last Sample data
234  * @min_perf:		Minimum capacity limit as a fraction of the maximum
235  *			turbo P-state capacity.
236  * @max_perf:		Maximum capacity limit as a fraction of the maximum
237  *			turbo P-state capacity.
238  * @acpi_perf_data:	Stores ACPI perf information read from _PSS
239  * @valid_pss_table:	Set to true for valid ACPI _PSS entries found
240  * @epp_powersave:	Last saved HWP energy performance preference
241  *			(EPP) or energy performance bias (EPB),
242  *			when policy switched to performance
243  * @epp_policy:		Last saved policy used to set EPP/EPB
244  * @epp_default:	Power on default HWP energy performance
245  *			preference/bias
246  * @epp_saved:		Saved EPP/EPB during system suspend or CPU offline
247  *			operation
248  *
249  * This structure stores per CPU instance data for all CPUs.
250  */
251 struct cpudata {
252 	int cpu;
253 
254 	unsigned int policy;
255 	struct update_util_data update_util;
256 	bool   update_util_set;
257 
258 	struct pstate_data pstate;
259 	struct vid_data vid;
260 	struct _pid pid;
261 
262 	u64	last_update;
263 	u64	last_sample_time;
264 	u64	prev_aperf;
265 	u64	prev_mperf;
266 	u64	prev_tsc;
267 	u64	prev_cummulative_iowait;
268 	struct sample sample;
269 	int32_t	min_perf;
270 	int32_t	max_perf;
271 #ifdef CONFIG_ACPI
272 	struct acpi_processor_performance acpi_perf_data;
273 	bool valid_pss_table;
274 #endif
275 	unsigned int iowait_boost;
276 	s16 epp_powersave;
277 	s16 epp_policy;
278 	s16 epp_default;
279 	s16 epp_saved;
280 };
281 
282 static struct cpudata **all_cpu_data;
283 
284 /**
285  * struct pstate_adjust_policy - Stores static PID configuration data
286  * @sample_rate_ms:	PID calculation sample rate in ms
287  * @sample_rate_ns:	Sample rate calculation in ns
288  * @deadband:		PID deadband
289  * @setpoint:		PID Setpoint
290  * @p_gain_pct:		PID proportional gain
291  * @i_gain_pct:		PID integral gain
292  * @d_gain_pct:		PID derivative gain
293  *
294  * Stores per CPU model static PID configuration data.
295  */
296 struct pstate_adjust_policy {
297 	int sample_rate_ms;
298 	s64 sample_rate_ns;
299 	int deadband;
300 	int setpoint;
301 	int p_gain_pct;
302 	int d_gain_pct;
303 	int i_gain_pct;
304 };
305 
306 /**
307  * struct pstate_funcs - Per CPU model specific callbacks
308  * @get_max:		Callback to get maximum non turbo effective P state
309  * @get_max_physical:	Callback to get maximum non turbo physical P state
310  * @get_min:		Callback to get minimum P state
311  * @get_turbo:		Callback to get turbo P state
312  * @get_scaling:	Callback to get frequency scaling factor
313  * @get_val:		Callback to convert P state to actual MSR write value
314  * @get_vid:		Callback to get VID data for Atom platforms
315  * @update_util:	Active mode utilization update callback.
316  *
317  * Core and Atom CPU models have different way to get P State limits. This
318  * structure is used to store those callbacks.
319  */
320 struct pstate_funcs {
321 	int (*get_max)(void);
322 	int (*get_max_physical)(void);
323 	int (*get_min)(void);
324 	int (*get_turbo)(void);
325 	int (*get_scaling)(void);
326 	u64 (*get_val)(struct cpudata*, int pstate);
327 	void (*get_vid)(struct cpudata *);
328 	void (*update_util)(struct update_util_data *data, u64 time,
329 			    unsigned int flags);
330 };
331 
332 static struct pstate_funcs pstate_funcs __read_mostly;
333 static struct pstate_adjust_policy pid_params __read_mostly = {
334 	.sample_rate_ms = 10,
335 	.sample_rate_ns = 10 * NSEC_PER_MSEC,
336 	.deadband = 0,
337 	.setpoint = 97,
338 	.p_gain_pct = 20,
339 	.d_gain_pct = 0,
340 	.i_gain_pct = 0,
341 };
342 
343 static int hwp_active __read_mostly;
344 static bool per_cpu_limits __read_mostly;
345 
346 static struct cpufreq_driver *intel_pstate_driver __read_mostly;
347 
348 #ifdef CONFIG_ACPI
349 static bool acpi_ppc;
350 #endif
351 
352 static struct global_params global;
353 
354 static DEFINE_MUTEX(intel_pstate_driver_lock);
355 static DEFINE_MUTEX(intel_pstate_limits_lock);
356 
357 #ifdef CONFIG_ACPI
358 
359 static bool intel_pstate_get_ppc_enable_status(void)
360 {
361 	if (acpi_gbl_FADT.preferred_profile == PM_ENTERPRISE_SERVER ||
362 	    acpi_gbl_FADT.preferred_profile == PM_PERFORMANCE_SERVER)
363 		return true;
364 
365 	return acpi_ppc;
366 }
367 
368 #ifdef CONFIG_ACPI_CPPC_LIB
369 
370 /* The work item is needed to avoid CPU hotplug locking issues */
371 static void intel_pstste_sched_itmt_work_fn(struct work_struct *work)
372 {
373 	sched_set_itmt_support();
374 }
375 
376 static DECLARE_WORK(sched_itmt_work, intel_pstste_sched_itmt_work_fn);
377 
378 static void intel_pstate_set_itmt_prio(int cpu)
379 {
380 	struct cppc_perf_caps cppc_perf;
381 	static u32 max_highest_perf = 0, min_highest_perf = U32_MAX;
382 	int ret;
383 
384 	ret = cppc_get_perf_caps(cpu, &cppc_perf);
385 	if (ret)
386 		return;
387 
388 	/*
389 	 * The priorities can be set regardless of whether or not
390 	 * sched_set_itmt_support(true) has been called and it is valid to
391 	 * update them at any time after it has been called.
392 	 */
393 	sched_set_itmt_core_prio(cppc_perf.highest_perf, cpu);
394 
395 	if (max_highest_perf <= min_highest_perf) {
396 		if (cppc_perf.highest_perf > max_highest_perf)
397 			max_highest_perf = cppc_perf.highest_perf;
398 
399 		if (cppc_perf.highest_perf < min_highest_perf)
400 			min_highest_perf = cppc_perf.highest_perf;
401 
402 		if (max_highest_perf > min_highest_perf) {
403 			/*
404 			 * This code can be run during CPU online under the
405 			 * CPU hotplug locks, so sched_set_itmt_support()
406 			 * cannot be called from here.  Queue up a work item
407 			 * to invoke it.
408 			 */
409 			schedule_work(&sched_itmt_work);
410 		}
411 	}
412 }
413 #else
414 static void intel_pstate_set_itmt_prio(int cpu)
415 {
416 }
417 #endif
418 
419 static void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy)
420 {
421 	struct cpudata *cpu;
422 	int ret;
423 	int i;
424 
425 	if (hwp_active) {
426 		intel_pstate_set_itmt_prio(policy->cpu);
427 		return;
428 	}
429 
430 	if (!intel_pstate_get_ppc_enable_status())
431 		return;
432 
433 	cpu = all_cpu_data[policy->cpu];
434 
435 	ret = acpi_processor_register_performance(&cpu->acpi_perf_data,
436 						  policy->cpu);
437 	if (ret)
438 		return;
439 
440 	/*
441 	 * Check if the control value in _PSS is for PERF_CTL MSR, which should
442 	 * guarantee that the states returned by it map to the states in our
443 	 * list directly.
444 	 */
445 	if (cpu->acpi_perf_data.control_register.space_id !=
446 						ACPI_ADR_SPACE_FIXED_HARDWARE)
447 		goto err;
448 
449 	/*
450 	 * If there is only one entry _PSS, simply ignore _PSS and continue as
451 	 * usual without taking _PSS into account
452 	 */
453 	if (cpu->acpi_perf_data.state_count < 2)
454 		goto err;
455 
456 	pr_debug("CPU%u - ACPI _PSS perf data\n", policy->cpu);
457 	for (i = 0; i < cpu->acpi_perf_data.state_count; i++) {
458 		pr_debug("     %cP%d: %u MHz, %u mW, 0x%x\n",
459 			 (i == cpu->acpi_perf_data.state ? '*' : ' '), i,
460 			 (u32) cpu->acpi_perf_data.states[i].core_frequency,
461 			 (u32) cpu->acpi_perf_data.states[i].power,
462 			 (u32) cpu->acpi_perf_data.states[i].control);
463 	}
464 
465 	/*
466 	 * The _PSS table doesn't contain whole turbo frequency range.
467 	 * This just contains +1 MHZ above the max non turbo frequency,
468 	 * with control value corresponding to max turbo ratio. But
469 	 * when cpufreq set policy is called, it will call with this
470 	 * max frequency, which will cause a reduced performance as
471 	 * this driver uses real max turbo frequency as the max
472 	 * frequency. So correct this frequency in _PSS table to
473 	 * correct max turbo frequency based on the turbo state.
474 	 * Also need to convert to MHz as _PSS freq is in MHz.
475 	 */
476 	if (!global.turbo_disabled)
477 		cpu->acpi_perf_data.states[0].core_frequency =
478 					policy->cpuinfo.max_freq / 1000;
479 	cpu->valid_pss_table = true;
480 	pr_debug("_PPC limits will be enforced\n");
481 
482 	return;
483 
484  err:
485 	cpu->valid_pss_table = false;
486 	acpi_processor_unregister_performance(policy->cpu);
487 }
488 
489 static void intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
490 {
491 	struct cpudata *cpu;
492 
493 	cpu = all_cpu_data[policy->cpu];
494 	if (!cpu->valid_pss_table)
495 		return;
496 
497 	acpi_processor_unregister_performance(policy->cpu);
498 }
499 #else
500 static inline void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy)
501 {
502 }
503 
504 static inline void intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
505 {
506 }
507 #endif
508 
509 static signed int pid_calc(struct _pid *pid, int32_t busy)
510 {
511 	signed int result;
512 	int32_t pterm, dterm, fp_error;
513 	int32_t integral_limit;
514 
515 	fp_error = pid->setpoint - busy;
516 
517 	if (abs(fp_error) <= pid->deadband)
518 		return 0;
519 
520 	pterm = mul_fp(pid->p_gain, fp_error);
521 
522 	pid->integral += fp_error;
523 
524 	/*
525 	 * We limit the integral here so that it will never
526 	 * get higher than 30.  This prevents it from becoming
527 	 * too large an input over long periods of time and allows
528 	 * it to get factored out sooner.
529 	 *
530 	 * The value of 30 was chosen through experimentation.
531 	 */
532 	integral_limit = int_tofp(30);
533 	if (pid->integral > integral_limit)
534 		pid->integral = integral_limit;
535 	if (pid->integral < -integral_limit)
536 		pid->integral = -integral_limit;
537 
538 	dterm = mul_fp(pid->d_gain, fp_error - pid->last_err);
539 	pid->last_err = fp_error;
540 
541 	result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm;
542 	result = result + (1 << (FRAC_BITS-1));
543 	return (signed int)fp_toint(result);
544 }
545 
546 static inline void intel_pstate_pid_reset(struct cpudata *cpu)
547 {
548 	struct _pid *pid = &cpu->pid;
549 
550 	pid->p_gain = percent_fp(pid_params.p_gain_pct);
551 	pid->d_gain = percent_fp(pid_params.d_gain_pct);
552 	pid->i_gain = percent_fp(pid_params.i_gain_pct);
553 	pid->setpoint = int_tofp(pid_params.setpoint);
554 	pid->last_err  = pid->setpoint - int_tofp(100);
555 	pid->deadband  = int_tofp(pid_params.deadband);
556 	pid->integral  = 0;
557 }
558 
559 static inline void update_turbo_state(void)
560 {
561 	u64 misc_en;
562 	struct cpudata *cpu;
563 
564 	cpu = all_cpu_data[0];
565 	rdmsrl(MSR_IA32_MISC_ENABLE, misc_en);
566 	global.turbo_disabled =
567 		(misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE ||
568 		 cpu->pstate.max_pstate == cpu->pstate.turbo_pstate);
569 }
570 
571 static int min_perf_pct_min(void)
572 {
573 	struct cpudata *cpu = all_cpu_data[0];
574 	int turbo_pstate = cpu->pstate.turbo_pstate;
575 
576 	return turbo_pstate ?
577 		DIV_ROUND_UP(cpu->pstate.min_pstate * 100, turbo_pstate) : 0;
578 }
579 
580 static s16 intel_pstate_get_epb(struct cpudata *cpu_data)
581 {
582 	u64 epb;
583 	int ret;
584 
585 	if (!static_cpu_has(X86_FEATURE_EPB))
586 		return -ENXIO;
587 
588 	ret = rdmsrl_on_cpu(cpu_data->cpu, MSR_IA32_ENERGY_PERF_BIAS, &epb);
589 	if (ret)
590 		return (s16)ret;
591 
592 	return (s16)(epb & 0x0f);
593 }
594 
595 static s16 intel_pstate_get_epp(struct cpudata *cpu_data, u64 hwp_req_data)
596 {
597 	s16 epp;
598 
599 	if (static_cpu_has(X86_FEATURE_HWP_EPP)) {
600 		/*
601 		 * When hwp_req_data is 0, means that caller didn't read
602 		 * MSR_HWP_REQUEST, so need to read and get EPP.
603 		 */
604 		if (!hwp_req_data) {
605 			epp = rdmsrl_on_cpu(cpu_data->cpu, MSR_HWP_REQUEST,
606 					    &hwp_req_data);
607 			if (epp)
608 				return epp;
609 		}
610 		epp = (hwp_req_data >> 24) & 0xff;
611 	} else {
612 		/* When there is no EPP present, HWP uses EPB settings */
613 		epp = intel_pstate_get_epb(cpu_data);
614 	}
615 
616 	return epp;
617 }
618 
619 static int intel_pstate_set_epb(int cpu, s16 pref)
620 {
621 	u64 epb;
622 	int ret;
623 
624 	if (!static_cpu_has(X86_FEATURE_EPB))
625 		return -ENXIO;
626 
627 	ret = rdmsrl_on_cpu(cpu, MSR_IA32_ENERGY_PERF_BIAS, &epb);
628 	if (ret)
629 		return ret;
630 
631 	epb = (epb & ~0x0f) | pref;
632 	wrmsrl_on_cpu(cpu, MSR_IA32_ENERGY_PERF_BIAS, epb);
633 
634 	return 0;
635 }
636 
637 /*
638  * EPP/EPB display strings corresponding to EPP index in the
639  * energy_perf_strings[]
640  *	index		String
641  *-------------------------------------
642  *	0		default
643  *	1		performance
644  *	2		balance_performance
645  *	3		balance_power
646  *	4		power
647  */
648 static const char * const energy_perf_strings[] = {
649 	"default",
650 	"performance",
651 	"balance_performance",
652 	"balance_power",
653 	"power",
654 	NULL
655 };
656 
657 static int intel_pstate_get_energy_pref_index(struct cpudata *cpu_data)
658 {
659 	s16 epp;
660 	int index = -EINVAL;
661 
662 	epp = intel_pstate_get_epp(cpu_data, 0);
663 	if (epp < 0)
664 		return epp;
665 
666 	if (static_cpu_has(X86_FEATURE_HWP_EPP)) {
667 		/*
668 		 * Range:
669 		 *	0x00-0x3F	:	Performance
670 		 *	0x40-0x7F	:	Balance performance
671 		 *	0x80-0xBF	:	Balance power
672 		 *	0xC0-0xFF	:	Power
673 		 * The EPP is a 8 bit value, but our ranges restrict the
674 		 * value which can be set. Here only using top two bits
675 		 * effectively.
676 		 */
677 		index = (epp >> 6) + 1;
678 	} else if (static_cpu_has(X86_FEATURE_EPB)) {
679 		/*
680 		 * Range:
681 		 *	0x00-0x03	:	Performance
682 		 *	0x04-0x07	:	Balance performance
683 		 *	0x08-0x0B	:	Balance power
684 		 *	0x0C-0x0F	:	Power
685 		 * The EPB is a 4 bit value, but our ranges restrict the
686 		 * value which can be set. Here only using top two bits
687 		 * effectively.
688 		 */
689 		index = (epp >> 2) + 1;
690 	}
691 
692 	return index;
693 }
694 
695 static int intel_pstate_set_energy_pref_index(struct cpudata *cpu_data,
696 					      int pref_index)
697 {
698 	int epp = -EINVAL;
699 	int ret;
700 
701 	if (!pref_index)
702 		epp = cpu_data->epp_default;
703 
704 	mutex_lock(&intel_pstate_limits_lock);
705 
706 	if (static_cpu_has(X86_FEATURE_HWP_EPP)) {
707 		u64 value;
708 
709 		ret = rdmsrl_on_cpu(cpu_data->cpu, MSR_HWP_REQUEST, &value);
710 		if (ret)
711 			goto return_pref;
712 
713 		value &= ~GENMASK_ULL(31, 24);
714 
715 		/*
716 		 * If epp is not default, convert from index into
717 		 * energy_perf_strings to epp value, by shifting 6
718 		 * bits left to use only top two bits in epp.
719 		 * The resultant epp need to shifted by 24 bits to
720 		 * epp position in MSR_HWP_REQUEST.
721 		 */
722 		if (epp == -EINVAL)
723 			epp = (pref_index - 1) << 6;
724 
725 		value |= (u64)epp << 24;
726 		ret = wrmsrl_on_cpu(cpu_data->cpu, MSR_HWP_REQUEST, value);
727 	} else {
728 		if (epp == -EINVAL)
729 			epp = (pref_index - 1) << 2;
730 		ret = intel_pstate_set_epb(cpu_data->cpu, epp);
731 	}
732 return_pref:
733 	mutex_unlock(&intel_pstate_limits_lock);
734 
735 	return ret;
736 }
737 
738 static ssize_t show_energy_performance_available_preferences(
739 				struct cpufreq_policy *policy, char *buf)
740 {
741 	int i = 0;
742 	int ret = 0;
743 
744 	while (energy_perf_strings[i] != NULL)
745 		ret += sprintf(&buf[ret], "%s ", energy_perf_strings[i++]);
746 
747 	ret += sprintf(&buf[ret], "\n");
748 
749 	return ret;
750 }
751 
752 cpufreq_freq_attr_ro(energy_performance_available_preferences);
753 
754 static ssize_t store_energy_performance_preference(
755 		struct cpufreq_policy *policy, const char *buf, size_t count)
756 {
757 	struct cpudata *cpu_data = all_cpu_data[policy->cpu];
758 	char str_preference[21];
759 	int ret, i = 0;
760 
761 	ret = sscanf(buf, "%20s", str_preference);
762 	if (ret != 1)
763 		return -EINVAL;
764 
765 	while (energy_perf_strings[i] != NULL) {
766 		if (!strcmp(str_preference, energy_perf_strings[i])) {
767 			intel_pstate_set_energy_pref_index(cpu_data, i);
768 			return count;
769 		}
770 		++i;
771 	}
772 
773 	return -EINVAL;
774 }
775 
776 static ssize_t show_energy_performance_preference(
777 				struct cpufreq_policy *policy, char *buf)
778 {
779 	struct cpudata *cpu_data = all_cpu_data[policy->cpu];
780 	int preference;
781 
782 	preference = intel_pstate_get_energy_pref_index(cpu_data);
783 	if (preference < 0)
784 		return preference;
785 
786 	return  sprintf(buf, "%s\n", energy_perf_strings[preference]);
787 }
788 
789 cpufreq_freq_attr_rw(energy_performance_preference);
790 
791 static struct freq_attr *hwp_cpufreq_attrs[] = {
792 	&energy_performance_preference,
793 	&energy_performance_available_preferences,
794 	NULL,
795 };
796 
797 static void intel_pstate_hwp_set(unsigned int cpu)
798 {
799 	struct cpudata *cpu_data = all_cpu_data[cpu];
800 	int min, hw_min, max, hw_max;
801 	u64 value, cap;
802 	s16 epp;
803 
804 	rdmsrl_on_cpu(cpu, MSR_HWP_CAPABILITIES, &cap);
805 	hw_min = HWP_LOWEST_PERF(cap);
806 	if (global.no_turbo)
807 		hw_max = HWP_GUARANTEED_PERF(cap);
808 	else
809 		hw_max = HWP_HIGHEST_PERF(cap);
810 
811 	max = fp_ext_toint(hw_max * cpu_data->max_perf);
812 	if (cpu_data->policy == CPUFREQ_POLICY_PERFORMANCE)
813 		min = max;
814 	else
815 		min = fp_ext_toint(hw_max * cpu_data->min_perf);
816 
817 	rdmsrl_on_cpu(cpu, MSR_HWP_REQUEST, &value);
818 
819 	value &= ~HWP_MIN_PERF(~0L);
820 	value |= HWP_MIN_PERF(min);
821 
822 	value &= ~HWP_MAX_PERF(~0L);
823 	value |= HWP_MAX_PERF(max);
824 
825 	if (cpu_data->epp_policy == cpu_data->policy)
826 		goto skip_epp;
827 
828 	cpu_data->epp_policy = cpu_data->policy;
829 
830 	if (cpu_data->epp_saved >= 0) {
831 		epp = cpu_data->epp_saved;
832 		cpu_data->epp_saved = -EINVAL;
833 		goto update_epp;
834 	}
835 
836 	if (cpu_data->policy == CPUFREQ_POLICY_PERFORMANCE) {
837 		epp = intel_pstate_get_epp(cpu_data, value);
838 		cpu_data->epp_powersave = epp;
839 		/* If EPP read was failed, then don't try to write */
840 		if (epp < 0)
841 			goto skip_epp;
842 
843 		epp = 0;
844 	} else {
845 		/* skip setting EPP, when saved value is invalid */
846 		if (cpu_data->epp_powersave < 0)
847 			goto skip_epp;
848 
849 		/*
850 		 * No need to restore EPP when it is not zero. This
851 		 * means:
852 		 *  - Policy is not changed
853 		 *  - user has manually changed
854 		 *  - Error reading EPB
855 		 */
856 		epp = intel_pstate_get_epp(cpu_data, value);
857 		if (epp)
858 			goto skip_epp;
859 
860 		epp = cpu_data->epp_powersave;
861 	}
862 update_epp:
863 	if (static_cpu_has(X86_FEATURE_HWP_EPP)) {
864 		value &= ~GENMASK_ULL(31, 24);
865 		value |= (u64)epp << 24;
866 	} else {
867 		intel_pstate_set_epb(cpu, epp);
868 	}
869 skip_epp:
870 	wrmsrl_on_cpu(cpu, MSR_HWP_REQUEST, value);
871 }
872 
873 static int intel_pstate_hwp_save_state(struct cpufreq_policy *policy)
874 {
875 	struct cpudata *cpu_data = all_cpu_data[policy->cpu];
876 
877 	if (!hwp_active)
878 		return 0;
879 
880 	cpu_data->epp_saved = intel_pstate_get_epp(cpu_data, 0);
881 
882 	return 0;
883 }
884 
885 static int intel_pstate_resume(struct cpufreq_policy *policy)
886 {
887 	if (!hwp_active)
888 		return 0;
889 
890 	mutex_lock(&intel_pstate_limits_lock);
891 
892 	all_cpu_data[policy->cpu]->epp_policy = 0;
893 	intel_pstate_hwp_set(policy->cpu);
894 
895 	mutex_unlock(&intel_pstate_limits_lock);
896 
897 	return 0;
898 }
899 
900 static void intel_pstate_update_policies(void)
901 {
902 	int cpu;
903 
904 	for_each_possible_cpu(cpu)
905 		cpufreq_update_policy(cpu);
906 }
907 
908 /************************** debugfs begin ************************/
909 static int pid_param_set(void *data, u64 val)
910 {
911 	unsigned int cpu;
912 
913 	*(u32 *)data = val;
914 	pid_params.sample_rate_ns = pid_params.sample_rate_ms * NSEC_PER_MSEC;
915 	for_each_possible_cpu(cpu)
916 		if (all_cpu_data[cpu])
917 			intel_pstate_pid_reset(all_cpu_data[cpu]);
918 
919 	return 0;
920 }
921 
922 static int pid_param_get(void *data, u64 *val)
923 {
924 	*val = *(u32 *)data;
925 	return 0;
926 }
927 DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get, pid_param_set, "%llu\n");
928 
929 static struct dentry *debugfs_parent;
930 
931 struct pid_param {
932 	char *name;
933 	void *value;
934 	struct dentry *dentry;
935 };
936 
937 static struct pid_param pid_files[] = {
938 	{"sample_rate_ms", &pid_params.sample_rate_ms, },
939 	{"d_gain_pct", &pid_params.d_gain_pct, },
940 	{"i_gain_pct", &pid_params.i_gain_pct, },
941 	{"deadband", &pid_params.deadband, },
942 	{"setpoint", &pid_params.setpoint, },
943 	{"p_gain_pct", &pid_params.p_gain_pct, },
944 	{NULL, NULL, }
945 };
946 
947 static void intel_pstate_debug_expose_params(void)
948 {
949 	int i;
950 
951 	debugfs_parent = debugfs_create_dir("pstate_snb", NULL);
952 	if (IS_ERR_OR_NULL(debugfs_parent))
953 		return;
954 
955 	for (i = 0; pid_files[i].name; i++) {
956 		struct dentry *dentry;
957 
958 		dentry = debugfs_create_file(pid_files[i].name, 0660,
959 					     debugfs_parent, pid_files[i].value,
960 					     &fops_pid_param);
961 		if (!IS_ERR(dentry))
962 			pid_files[i].dentry = dentry;
963 	}
964 }
965 
966 static void intel_pstate_debug_hide_params(void)
967 {
968 	int i;
969 
970 	if (IS_ERR_OR_NULL(debugfs_parent))
971 		return;
972 
973 	for (i = 0; pid_files[i].name; i++) {
974 		debugfs_remove(pid_files[i].dentry);
975 		pid_files[i].dentry = NULL;
976 	}
977 
978 	debugfs_remove(debugfs_parent);
979 	debugfs_parent = NULL;
980 }
981 
982 /************************** debugfs end ************************/
983 
984 /************************** sysfs begin ************************/
985 #define show_one(file_name, object)					\
986 	static ssize_t show_##file_name					\
987 	(struct kobject *kobj, struct attribute *attr, char *buf)	\
988 	{								\
989 		return sprintf(buf, "%u\n", global.object);		\
990 	}
991 
992 static ssize_t intel_pstate_show_status(char *buf);
993 static int intel_pstate_update_status(const char *buf, size_t size);
994 
995 static ssize_t show_status(struct kobject *kobj,
996 			   struct attribute *attr, char *buf)
997 {
998 	ssize_t ret;
999 
1000 	mutex_lock(&intel_pstate_driver_lock);
1001 	ret = intel_pstate_show_status(buf);
1002 	mutex_unlock(&intel_pstate_driver_lock);
1003 
1004 	return ret;
1005 }
1006 
1007 static ssize_t store_status(struct kobject *a, struct attribute *b,
1008 			    const char *buf, size_t count)
1009 {
1010 	char *p = memchr(buf, '\n', count);
1011 	int ret;
1012 
1013 	mutex_lock(&intel_pstate_driver_lock);
1014 	ret = intel_pstate_update_status(buf, p ? p - buf : count);
1015 	mutex_unlock(&intel_pstate_driver_lock);
1016 
1017 	return ret < 0 ? ret : count;
1018 }
1019 
1020 static ssize_t show_turbo_pct(struct kobject *kobj,
1021 				struct attribute *attr, char *buf)
1022 {
1023 	struct cpudata *cpu;
1024 	int total, no_turbo, turbo_pct;
1025 	uint32_t turbo_fp;
1026 
1027 	mutex_lock(&intel_pstate_driver_lock);
1028 
1029 	if (!intel_pstate_driver) {
1030 		mutex_unlock(&intel_pstate_driver_lock);
1031 		return -EAGAIN;
1032 	}
1033 
1034 	cpu = all_cpu_data[0];
1035 
1036 	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
1037 	no_turbo = cpu->pstate.max_pstate - cpu->pstate.min_pstate + 1;
1038 	turbo_fp = div_fp(no_turbo, total);
1039 	turbo_pct = 100 - fp_toint(mul_fp(turbo_fp, int_tofp(100)));
1040 
1041 	mutex_unlock(&intel_pstate_driver_lock);
1042 
1043 	return sprintf(buf, "%u\n", turbo_pct);
1044 }
1045 
1046 static ssize_t show_num_pstates(struct kobject *kobj,
1047 				struct attribute *attr, char *buf)
1048 {
1049 	struct cpudata *cpu;
1050 	int total;
1051 
1052 	mutex_lock(&intel_pstate_driver_lock);
1053 
1054 	if (!intel_pstate_driver) {
1055 		mutex_unlock(&intel_pstate_driver_lock);
1056 		return -EAGAIN;
1057 	}
1058 
1059 	cpu = all_cpu_data[0];
1060 	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
1061 
1062 	mutex_unlock(&intel_pstate_driver_lock);
1063 
1064 	return sprintf(buf, "%u\n", total);
1065 }
1066 
1067 static ssize_t show_no_turbo(struct kobject *kobj,
1068 			     struct attribute *attr, char *buf)
1069 {
1070 	ssize_t ret;
1071 
1072 	mutex_lock(&intel_pstate_driver_lock);
1073 
1074 	if (!intel_pstate_driver) {
1075 		mutex_unlock(&intel_pstate_driver_lock);
1076 		return -EAGAIN;
1077 	}
1078 
1079 	update_turbo_state();
1080 	if (global.turbo_disabled)
1081 		ret = sprintf(buf, "%u\n", global.turbo_disabled);
1082 	else
1083 		ret = sprintf(buf, "%u\n", global.no_turbo);
1084 
1085 	mutex_unlock(&intel_pstate_driver_lock);
1086 
1087 	return ret;
1088 }
1089 
1090 static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
1091 			      const char *buf, size_t count)
1092 {
1093 	unsigned int input;
1094 	int ret;
1095 
1096 	ret = sscanf(buf, "%u", &input);
1097 	if (ret != 1)
1098 		return -EINVAL;
1099 
1100 	mutex_lock(&intel_pstate_driver_lock);
1101 
1102 	if (!intel_pstate_driver) {
1103 		mutex_unlock(&intel_pstate_driver_lock);
1104 		return -EAGAIN;
1105 	}
1106 
1107 	mutex_lock(&intel_pstate_limits_lock);
1108 
1109 	update_turbo_state();
1110 	if (global.turbo_disabled) {
1111 		pr_warn("Turbo disabled by BIOS or unavailable on processor\n");
1112 		mutex_unlock(&intel_pstate_limits_lock);
1113 		mutex_unlock(&intel_pstate_driver_lock);
1114 		return -EPERM;
1115 	}
1116 
1117 	global.no_turbo = clamp_t(int, input, 0, 1);
1118 
1119 	if (global.no_turbo) {
1120 		struct cpudata *cpu = all_cpu_data[0];
1121 		int pct = cpu->pstate.max_pstate * 100 / cpu->pstate.turbo_pstate;
1122 
1123 		/* Squash the global minimum into the permitted range. */
1124 		if (global.min_perf_pct > pct)
1125 			global.min_perf_pct = pct;
1126 	}
1127 
1128 	mutex_unlock(&intel_pstate_limits_lock);
1129 
1130 	intel_pstate_update_policies();
1131 
1132 	mutex_unlock(&intel_pstate_driver_lock);
1133 
1134 	return count;
1135 }
1136 
1137 static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
1138 				  const char *buf, size_t count)
1139 {
1140 	unsigned int input;
1141 	int ret;
1142 
1143 	ret = sscanf(buf, "%u", &input);
1144 	if (ret != 1)
1145 		return -EINVAL;
1146 
1147 	mutex_lock(&intel_pstate_driver_lock);
1148 
1149 	if (!intel_pstate_driver) {
1150 		mutex_unlock(&intel_pstate_driver_lock);
1151 		return -EAGAIN;
1152 	}
1153 
1154 	mutex_lock(&intel_pstate_limits_lock);
1155 
1156 	global.max_perf_pct = clamp_t(int, input, global.min_perf_pct, 100);
1157 
1158 	mutex_unlock(&intel_pstate_limits_lock);
1159 
1160 	intel_pstate_update_policies();
1161 
1162 	mutex_unlock(&intel_pstate_driver_lock);
1163 
1164 	return count;
1165 }
1166 
1167 static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
1168 				  const char *buf, size_t count)
1169 {
1170 	unsigned int input;
1171 	int ret;
1172 
1173 	ret = sscanf(buf, "%u", &input);
1174 	if (ret != 1)
1175 		return -EINVAL;
1176 
1177 	mutex_lock(&intel_pstate_driver_lock);
1178 
1179 	if (!intel_pstate_driver) {
1180 		mutex_unlock(&intel_pstate_driver_lock);
1181 		return -EAGAIN;
1182 	}
1183 
1184 	mutex_lock(&intel_pstate_limits_lock);
1185 
1186 	global.min_perf_pct = clamp_t(int, input,
1187 				      min_perf_pct_min(), global.max_perf_pct);
1188 
1189 	mutex_unlock(&intel_pstate_limits_lock);
1190 
1191 	intel_pstate_update_policies();
1192 
1193 	mutex_unlock(&intel_pstate_driver_lock);
1194 
1195 	return count;
1196 }
1197 
1198 show_one(max_perf_pct, max_perf_pct);
1199 show_one(min_perf_pct, min_perf_pct);
1200 
1201 define_one_global_rw(status);
1202 define_one_global_rw(no_turbo);
1203 define_one_global_rw(max_perf_pct);
1204 define_one_global_rw(min_perf_pct);
1205 define_one_global_ro(turbo_pct);
1206 define_one_global_ro(num_pstates);
1207 
1208 static struct attribute *intel_pstate_attributes[] = {
1209 	&status.attr,
1210 	&no_turbo.attr,
1211 	&turbo_pct.attr,
1212 	&num_pstates.attr,
1213 	NULL
1214 };
1215 
1216 static struct attribute_group intel_pstate_attr_group = {
1217 	.attrs = intel_pstate_attributes,
1218 };
1219 
1220 static void __init intel_pstate_sysfs_expose_params(void)
1221 {
1222 	struct kobject *intel_pstate_kobject;
1223 	int rc;
1224 
1225 	intel_pstate_kobject = kobject_create_and_add("intel_pstate",
1226 						&cpu_subsys.dev_root->kobj);
1227 	if (WARN_ON(!intel_pstate_kobject))
1228 		return;
1229 
1230 	rc = sysfs_create_group(intel_pstate_kobject, &intel_pstate_attr_group);
1231 	if (WARN_ON(rc))
1232 		return;
1233 
1234 	/*
1235 	 * If per cpu limits are enforced there are no global limits, so
1236 	 * return without creating max/min_perf_pct attributes
1237 	 */
1238 	if (per_cpu_limits)
1239 		return;
1240 
1241 	rc = sysfs_create_file(intel_pstate_kobject, &max_perf_pct.attr);
1242 	WARN_ON(rc);
1243 
1244 	rc = sysfs_create_file(intel_pstate_kobject, &min_perf_pct.attr);
1245 	WARN_ON(rc);
1246 
1247 }
1248 /************************** sysfs end ************************/
1249 
1250 static void intel_pstate_hwp_enable(struct cpudata *cpudata)
1251 {
1252 	/* First disable HWP notification interrupt as we don't process them */
1253 	if (static_cpu_has(X86_FEATURE_HWP_NOTIFY))
1254 		wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_INTERRUPT, 0x00);
1255 
1256 	wrmsrl_on_cpu(cpudata->cpu, MSR_PM_ENABLE, 0x1);
1257 	cpudata->epp_policy = 0;
1258 	if (cpudata->epp_default == -EINVAL)
1259 		cpudata->epp_default = intel_pstate_get_epp(cpudata, 0);
1260 }
1261 
1262 #define MSR_IA32_POWER_CTL_BIT_EE	19
1263 
1264 /* Disable energy efficiency optimization */
1265 static void intel_pstate_disable_ee(int cpu)
1266 {
1267 	u64 power_ctl;
1268 	int ret;
1269 
1270 	ret = rdmsrl_on_cpu(cpu, MSR_IA32_POWER_CTL, &power_ctl);
1271 	if (ret)
1272 		return;
1273 
1274 	if (!(power_ctl & BIT(MSR_IA32_POWER_CTL_BIT_EE))) {
1275 		pr_info("Disabling energy efficiency optimization\n");
1276 		power_ctl |= BIT(MSR_IA32_POWER_CTL_BIT_EE);
1277 		wrmsrl_on_cpu(cpu, MSR_IA32_POWER_CTL, power_ctl);
1278 	}
1279 }
1280 
1281 static int atom_get_min_pstate(void)
1282 {
1283 	u64 value;
1284 
1285 	rdmsrl(MSR_ATOM_CORE_RATIOS, value);
1286 	return (value >> 8) & 0x7F;
1287 }
1288 
1289 static int atom_get_max_pstate(void)
1290 {
1291 	u64 value;
1292 
1293 	rdmsrl(MSR_ATOM_CORE_RATIOS, value);
1294 	return (value >> 16) & 0x7F;
1295 }
1296 
1297 static int atom_get_turbo_pstate(void)
1298 {
1299 	u64 value;
1300 
1301 	rdmsrl(MSR_ATOM_CORE_TURBO_RATIOS, value);
1302 	return value & 0x7F;
1303 }
1304 
1305 static u64 atom_get_val(struct cpudata *cpudata, int pstate)
1306 {
1307 	u64 val;
1308 	int32_t vid_fp;
1309 	u32 vid;
1310 
1311 	val = (u64)pstate << 8;
1312 	if (global.no_turbo && !global.turbo_disabled)
1313 		val |= (u64)1 << 32;
1314 
1315 	vid_fp = cpudata->vid.min + mul_fp(
1316 		int_tofp(pstate - cpudata->pstate.min_pstate),
1317 		cpudata->vid.ratio);
1318 
1319 	vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
1320 	vid = ceiling_fp(vid_fp);
1321 
1322 	if (pstate > cpudata->pstate.max_pstate)
1323 		vid = cpudata->vid.turbo;
1324 
1325 	return val | vid;
1326 }
1327 
1328 static int silvermont_get_scaling(void)
1329 {
1330 	u64 value;
1331 	int i;
1332 	/* Defined in Table 35-6 from SDM (Sept 2015) */
1333 	static int silvermont_freq_table[] = {
1334 		83300, 100000, 133300, 116700, 80000};
1335 
1336 	rdmsrl(MSR_FSB_FREQ, value);
1337 	i = value & 0x7;
1338 	WARN_ON(i > 4);
1339 
1340 	return silvermont_freq_table[i];
1341 }
1342 
1343 static int airmont_get_scaling(void)
1344 {
1345 	u64 value;
1346 	int i;
1347 	/* Defined in Table 35-10 from SDM (Sept 2015) */
1348 	static int airmont_freq_table[] = {
1349 		83300, 100000, 133300, 116700, 80000,
1350 		93300, 90000, 88900, 87500};
1351 
1352 	rdmsrl(MSR_FSB_FREQ, value);
1353 	i = value & 0xF;
1354 	WARN_ON(i > 8);
1355 
1356 	return airmont_freq_table[i];
1357 }
1358 
1359 static void atom_get_vid(struct cpudata *cpudata)
1360 {
1361 	u64 value;
1362 
1363 	rdmsrl(MSR_ATOM_CORE_VIDS, value);
1364 	cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
1365 	cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
1366 	cpudata->vid.ratio = div_fp(
1367 		cpudata->vid.max - cpudata->vid.min,
1368 		int_tofp(cpudata->pstate.max_pstate -
1369 			cpudata->pstate.min_pstate));
1370 
1371 	rdmsrl(MSR_ATOM_CORE_TURBO_VIDS, value);
1372 	cpudata->vid.turbo = value & 0x7f;
1373 }
1374 
1375 static int core_get_min_pstate(void)
1376 {
1377 	u64 value;
1378 
1379 	rdmsrl(MSR_PLATFORM_INFO, value);
1380 	return (value >> 40) & 0xFF;
1381 }
1382 
1383 static int core_get_max_pstate_physical(void)
1384 {
1385 	u64 value;
1386 
1387 	rdmsrl(MSR_PLATFORM_INFO, value);
1388 	return (value >> 8) & 0xFF;
1389 }
1390 
1391 static int core_get_tdp_ratio(u64 plat_info)
1392 {
1393 	/* Check how many TDP levels present */
1394 	if (plat_info & 0x600000000) {
1395 		u64 tdp_ctrl;
1396 		u64 tdp_ratio;
1397 		int tdp_msr;
1398 		int err;
1399 
1400 		/* Get the TDP level (0, 1, 2) to get ratios */
1401 		err = rdmsrl_safe(MSR_CONFIG_TDP_CONTROL, &tdp_ctrl);
1402 		if (err)
1403 			return err;
1404 
1405 		/* TDP MSR are continuous starting at 0x648 */
1406 		tdp_msr = MSR_CONFIG_TDP_NOMINAL + (tdp_ctrl & 0x03);
1407 		err = rdmsrl_safe(tdp_msr, &tdp_ratio);
1408 		if (err)
1409 			return err;
1410 
1411 		/* For level 1 and 2, bits[23:16] contain the ratio */
1412 		if (tdp_ctrl & 0x03)
1413 			tdp_ratio >>= 16;
1414 
1415 		tdp_ratio &= 0xff; /* ratios are only 8 bits long */
1416 		pr_debug("tdp_ratio %x\n", (int)tdp_ratio);
1417 
1418 		return (int)tdp_ratio;
1419 	}
1420 
1421 	return -ENXIO;
1422 }
1423 
1424 static int core_get_max_pstate(void)
1425 {
1426 	u64 tar;
1427 	u64 plat_info;
1428 	int max_pstate;
1429 	int tdp_ratio;
1430 	int err;
1431 
1432 	rdmsrl(MSR_PLATFORM_INFO, plat_info);
1433 	max_pstate = (plat_info >> 8) & 0xFF;
1434 
1435 	tdp_ratio = core_get_tdp_ratio(plat_info);
1436 	if (tdp_ratio <= 0)
1437 		return max_pstate;
1438 
1439 	if (hwp_active) {
1440 		/* Turbo activation ratio is not used on HWP platforms */
1441 		return tdp_ratio;
1442 	}
1443 
1444 	err = rdmsrl_safe(MSR_TURBO_ACTIVATION_RATIO, &tar);
1445 	if (!err) {
1446 		int tar_levels;
1447 
1448 		/* Do some sanity checking for safety */
1449 		tar_levels = tar & 0xff;
1450 		if (tdp_ratio - 1 == tar_levels) {
1451 			max_pstate = tar_levels;
1452 			pr_debug("max_pstate=TAC %x\n", max_pstate);
1453 		}
1454 	}
1455 
1456 	return max_pstate;
1457 }
1458 
1459 static int core_get_turbo_pstate(void)
1460 {
1461 	u64 value;
1462 	int nont, ret;
1463 
1464 	rdmsrl(MSR_TURBO_RATIO_LIMIT, value);
1465 	nont = core_get_max_pstate();
1466 	ret = (value) & 255;
1467 	if (ret <= nont)
1468 		ret = nont;
1469 	return ret;
1470 }
1471 
1472 static inline int core_get_scaling(void)
1473 {
1474 	return 100000;
1475 }
1476 
1477 static u64 core_get_val(struct cpudata *cpudata, int pstate)
1478 {
1479 	u64 val;
1480 
1481 	val = (u64)pstate << 8;
1482 	if (global.no_turbo && !global.turbo_disabled)
1483 		val |= (u64)1 << 32;
1484 
1485 	return val;
1486 }
1487 
1488 static int knl_get_turbo_pstate(void)
1489 {
1490 	u64 value;
1491 	int nont, ret;
1492 
1493 	rdmsrl(MSR_TURBO_RATIO_LIMIT, value);
1494 	nont = core_get_max_pstate();
1495 	ret = (((value) >> 8) & 0xFF);
1496 	if (ret <= nont)
1497 		ret = nont;
1498 	return ret;
1499 }
1500 
1501 static int intel_pstate_get_base_pstate(struct cpudata *cpu)
1502 {
1503 	return global.no_turbo || global.turbo_disabled ?
1504 			cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
1505 }
1506 
1507 static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate)
1508 {
1509 	trace_cpu_frequency(pstate * cpu->pstate.scaling, cpu->cpu);
1510 	cpu->pstate.current_pstate = pstate;
1511 	/*
1512 	 * Generally, there is no guarantee that this code will always run on
1513 	 * the CPU being updated, so force the register update to run on the
1514 	 * right CPU.
1515 	 */
1516 	wrmsrl_on_cpu(cpu->cpu, MSR_IA32_PERF_CTL,
1517 		      pstate_funcs.get_val(cpu, pstate));
1518 }
1519 
1520 static void intel_pstate_set_min_pstate(struct cpudata *cpu)
1521 {
1522 	intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate);
1523 }
1524 
1525 static void intel_pstate_max_within_limits(struct cpudata *cpu)
1526 {
1527 	int pstate;
1528 
1529 	update_turbo_state();
1530 	pstate = intel_pstate_get_base_pstate(cpu);
1531 	pstate = max(cpu->pstate.min_pstate,
1532 		     fp_ext_toint(pstate * cpu->max_perf));
1533 	intel_pstate_set_pstate(cpu, pstate);
1534 }
1535 
1536 static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
1537 {
1538 	cpu->pstate.min_pstate = pstate_funcs.get_min();
1539 	cpu->pstate.max_pstate = pstate_funcs.get_max();
1540 	cpu->pstate.max_pstate_physical = pstate_funcs.get_max_physical();
1541 	cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
1542 	cpu->pstate.scaling = pstate_funcs.get_scaling();
1543 	cpu->pstate.max_freq = cpu->pstate.max_pstate * cpu->pstate.scaling;
1544 	cpu->pstate.turbo_freq = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
1545 
1546 	if (pstate_funcs.get_vid)
1547 		pstate_funcs.get_vid(cpu);
1548 
1549 	intel_pstate_set_min_pstate(cpu);
1550 }
1551 
1552 static inline void intel_pstate_calc_avg_perf(struct cpudata *cpu)
1553 {
1554 	struct sample *sample = &cpu->sample;
1555 
1556 	sample->core_avg_perf = div_ext_fp(sample->aperf, sample->mperf);
1557 }
1558 
1559 static inline bool intel_pstate_sample(struct cpudata *cpu, u64 time)
1560 {
1561 	u64 aperf, mperf;
1562 	unsigned long flags;
1563 	u64 tsc;
1564 
1565 	local_irq_save(flags);
1566 	rdmsrl(MSR_IA32_APERF, aperf);
1567 	rdmsrl(MSR_IA32_MPERF, mperf);
1568 	tsc = rdtsc();
1569 	if (cpu->prev_mperf == mperf || cpu->prev_tsc == tsc) {
1570 		local_irq_restore(flags);
1571 		return false;
1572 	}
1573 	local_irq_restore(flags);
1574 
1575 	cpu->last_sample_time = cpu->sample.time;
1576 	cpu->sample.time = time;
1577 	cpu->sample.aperf = aperf;
1578 	cpu->sample.mperf = mperf;
1579 	cpu->sample.tsc =  tsc;
1580 	cpu->sample.aperf -= cpu->prev_aperf;
1581 	cpu->sample.mperf -= cpu->prev_mperf;
1582 	cpu->sample.tsc -= cpu->prev_tsc;
1583 
1584 	cpu->prev_aperf = aperf;
1585 	cpu->prev_mperf = mperf;
1586 	cpu->prev_tsc = tsc;
1587 	/*
1588 	 * First time this function is invoked in a given cycle, all of the
1589 	 * previous sample data fields are equal to zero or stale and they must
1590 	 * be populated with meaningful numbers for things to work, so assume
1591 	 * that sample.time will always be reset before setting the utilization
1592 	 * update hook and make the caller skip the sample then.
1593 	 */
1594 	if (cpu->last_sample_time) {
1595 		intel_pstate_calc_avg_perf(cpu);
1596 		return true;
1597 	}
1598 	return false;
1599 }
1600 
1601 static inline int32_t get_avg_frequency(struct cpudata *cpu)
1602 {
1603 	return mul_ext_fp(cpu->sample.core_avg_perf,
1604 			  cpu->pstate.max_pstate_physical * cpu->pstate.scaling);
1605 }
1606 
1607 static inline int32_t get_avg_pstate(struct cpudata *cpu)
1608 {
1609 	return mul_ext_fp(cpu->pstate.max_pstate_physical,
1610 			  cpu->sample.core_avg_perf);
1611 }
1612 
1613 static inline int32_t get_target_pstate_use_cpu_load(struct cpudata *cpu)
1614 {
1615 	struct sample *sample = &cpu->sample;
1616 	int32_t busy_frac, boost;
1617 	int target, avg_pstate;
1618 
1619 	if (cpu->policy == CPUFREQ_POLICY_PERFORMANCE)
1620 		return cpu->pstate.turbo_pstate;
1621 
1622 	busy_frac = div_fp(sample->mperf, sample->tsc);
1623 
1624 	boost = cpu->iowait_boost;
1625 	cpu->iowait_boost >>= 1;
1626 
1627 	if (busy_frac < boost)
1628 		busy_frac = boost;
1629 
1630 	sample->busy_scaled = busy_frac * 100;
1631 
1632 	target = global.no_turbo || global.turbo_disabled ?
1633 			cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
1634 	target += target >> 2;
1635 	target = mul_fp(target, busy_frac);
1636 	if (target < cpu->pstate.min_pstate)
1637 		target = cpu->pstate.min_pstate;
1638 
1639 	/*
1640 	 * If the average P-state during the previous cycle was higher than the
1641 	 * current target, add 50% of the difference to the target to reduce
1642 	 * possible performance oscillations and offset possible performance
1643 	 * loss related to moving the workload from one CPU to another within
1644 	 * a package/module.
1645 	 */
1646 	avg_pstate = get_avg_pstate(cpu);
1647 	if (avg_pstate > target)
1648 		target += (avg_pstate - target) >> 1;
1649 
1650 	return target;
1651 }
1652 
1653 static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu)
1654 {
1655 	int32_t perf_scaled, max_pstate, current_pstate, sample_ratio;
1656 	u64 duration_ns;
1657 
1658 	if (cpu->policy == CPUFREQ_POLICY_PERFORMANCE)
1659 		return cpu->pstate.turbo_pstate;
1660 
1661 	/*
1662 	 * perf_scaled is the ratio of the average P-state during the last
1663 	 * sampling period to the P-state requested last time (in percent).
1664 	 *
1665 	 * That measures the system's response to the previous P-state
1666 	 * selection.
1667 	 */
1668 	max_pstate = cpu->pstate.max_pstate_physical;
1669 	current_pstate = cpu->pstate.current_pstate;
1670 	perf_scaled = mul_ext_fp(cpu->sample.core_avg_perf,
1671 			       div_fp(100 * max_pstate, current_pstate));
1672 
1673 	/*
1674 	 * Since our utilization update callback will not run unless we are
1675 	 * in C0, check if the actual elapsed time is significantly greater (3x)
1676 	 * than our sample interval.  If it is, then we were idle for a long
1677 	 * enough period of time to adjust our performance metric.
1678 	 */
1679 	duration_ns = cpu->sample.time - cpu->last_sample_time;
1680 	if ((s64)duration_ns > pid_params.sample_rate_ns * 3) {
1681 		sample_ratio = div_fp(pid_params.sample_rate_ns, duration_ns);
1682 		perf_scaled = mul_fp(perf_scaled, sample_ratio);
1683 	} else {
1684 		sample_ratio = div_fp(100 * cpu->sample.mperf, cpu->sample.tsc);
1685 		if (sample_ratio < int_tofp(1))
1686 			perf_scaled = 0;
1687 	}
1688 
1689 	cpu->sample.busy_scaled = perf_scaled;
1690 	return cpu->pstate.current_pstate - pid_calc(&cpu->pid, perf_scaled);
1691 }
1692 
1693 static int intel_pstate_prepare_request(struct cpudata *cpu, int pstate)
1694 {
1695 	int max_pstate = intel_pstate_get_base_pstate(cpu);
1696 	int min_pstate;
1697 
1698 	min_pstate = max(cpu->pstate.min_pstate,
1699 			 fp_ext_toint(max_pstate * cpu->min_perf));
1700 	max_pstate = max(min_pstate, fp_ext_toint(max_pstate * cpu->max_perf));
1701 	return clamp_t(int, pstate, min_pstate, max_pstate);
1702 }
1703 
1704 static void intel_pstate_update_pstate(struct cpudata *cpu, int pstate)
1705 {
1706 	if (pstate == cpu->pstate.current_pstate)
1707 		return;
1708 
1709 	cpu->pstate.current_pstate = pstate;
1710 	wrmsrl(MSR_IA32_PERF_CTL, pstate_funcs.get_val(cpu, pstate));
1711 }
1712 
1713 static void intel_pstate_adjust_pstate(struct cpudata *cpu, int target_pstate)
1714 {
1715 	int from = cpu->pstate.current_pstate;
1716 	struct sample *sample;
1717 
1718 	update_turbo_state();
1719 
1720 	target_pstate = intel_pstate_prepare_request(cpu, target_pstate);
1721 	trace_cpu_frequency(target_pstate * cpu->pstate.scaling, cpu->cpu);
1722 	intel_pstate_update_pstate(cpu, target_pstate);
1723 
1724 	sample = &cpu->sample;
1725 	trace_pstate_sample(mul_ext_fp(100, sample->core_avg_perf),
1726 		fp_toint(sample->busy_scaled),
1727 		from,
1728 		cpu->pstate.current_pstate,
1729 		sample->mperf,
1730 		sample->aperf,
1731 		sample->tsc,
1732 		get_avg_frequency(cpu),
1733 		fp_toint(cpu->iowait_boost * 100));
1734 }
1735 
1736 static void intel_pstate_update_util_hwp(struct update_util_data *data,
1737 					 u64 time, unsigned int flags)
1738 {
1739 	struct cpudata *cpu = container_of(data, struct cpudata, update_util);
1740 	u64 delta_ns = time - cpu->sample.time;
1741 
1742 	if ((s64)delta_ns >= INTEL_PSTATE_HWP_SAMPLING_INTERVAL)
1743 		intel_pstate_sample(cpu, time);
1744 }
1745 
1746 static void intel_pstate_update_util_pid(struct update_util_data *data,
1747 					 u64 time, unsigned int flags)
1748 {
1749 	struct cpudata *cpu = container_of(data, struct cpudata, update_util);
1750 	u64 delta_ns = time - cpu->sample.time;
1751 
1752 	if ((s64)delta_ns < pid_params.sample_rate_ns)
1753 		return;
1754 
1755 	if (intel_pstate_sample(cpu, time)) {
1756 		int target_pstate;
1757 
1758 		target_pstate = get_target_pstate_use_performance(cpu);
1759 		intel_pstate_adjust_pstate(cpu, target_pstate);
1760 	}
1761 }
1762 
1763 static void intel_pstate_update_util(struct update_util_data *data, u64 time,
1764 				     unsigned int flags)
1765 {
1766 	struct cpudata *cpu = container_of(data, struct cpudata, update_util);
1767 	u64 delta_ns;
1768 
1769 	if (flags & SCHED_CPUFREQ_IOWAIT) {
1770 		cpu->iowait_boost = int_tofp(1);
1771 	} else if (cpu->iowait_boost) {
1772 		/* Clear iowait_boost if the CPU may have been idle. */
1773 		delta_ns = time - cpu->last_update;
1774 		if (delta_ns > TICK_NSEC)
1775 			cpu->iowait_boost = 0;
1776 	}
1777 	cpu->last_update = time;
1778 	delta_ns = time - cpu->sample.time;
1779 	if ((s64)delta_ns < INTEL_PSTATE_DEFAULT_SAMPLING_INTERVAL)
1780 		return;
1781 
1782 	if (intel_pstate_sample(cpu, time)) {
1783 		int target_pstate;
1784 
1785 		target_pstate = get_target_pstate_use_cpu_load(cpu);
1786 		intel_pstate_adjust_pstate(cpu, target_pstate);
1787 	}
1788 }
1789 
1790 static struct pstate_funcs core_funcs = {
1791 	.get_max = core_get_max_pstate,
1792 	.get_max_physical = core_get_max_pstate_physical,
1793 	.get_min = core_get_min_pstate,
1794 	.get_turbo = core_get_turbo_pstate,
1795 	.get_scaling = core_get_scaling,
1796 	.get_val = core_get_val,
1797 	.update_util = intel_pstate_update_util_pid,
1798 };
1799 
1800 static const struct pstate_funcs silvermont_funcs = {
1801 	.get_max = atom_get_max_pstate,
1802 	.get_max_physical = atom_get_max_pstate,
1803 	.get_min = atom_get_min_pstate,
1804 	.get_turbo = atom_get_turbo_pstate,
1805 	.get_val = atom_get_val,
1806 	.get_scaling = silvermont_get_scaling,
1807 	.get_vid = atom_get_vid,
1808 	.update_util = intel_pstate_update_util,
1809 };
1810 
1811 static const struct pstate_funcs airmont_funcs = {
1812 	.get_max = atom_get_max_pstate,
1813 	.get_max_physical = atom_get_max_pstate,
1814 	.get_min = atom_get_min_pstate,
1815 	.get_turbo = atom_get_turbo_pstate,
1816 	.get_val = atom_get_val,
1817 	.get_scaling = airmont_get_scaling,
1818 	.get_vid = atom_get_vid,
1819 	.update_util = intel_pstate_update_util,
1820 };
1821 
1822 static const struct pstate_funcs knl_funcs = {
1823 	.get_max = core_get_max_pstate,
1824 	.get_max_physical = core_get_max_pstate_physical,
1825 	.get_min = core_get_min_pstate,
1826 	.get_turbo = knl_get_turbo_pstate,
1827 	.get_scaling = core_get_scaling,
1828 	.get_val = core_get_val,
1829 	.update_util = intel_pstate_update_util_pid,
1830 };
1831 
1832 static const struct pstate_funcs bxt_funcs = {
1833 	.get_max = core_get_max_pstate,
1834 	.get_max_physical = core_get_max_pstate_physical,
1835 	.get_min = core_get_min_pstate,
1836 	.get_turbo = core_get_turbo_pstate,
1837 	.get_scaling = core_get_scaling,
1838 	.get_val = core_get_val,
1839 	.update_util = intel_pstate_update_util,
1840 };
1841 
1842 #define ICPU(model, policy) \
1843 	{ X86_VENDOR_INTEL, 6, model, X86_FEATURE_APERFMPERF,\
1844 			(unsigned long)&policy }
1845 
1846 static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
1847 	ICPU(INTEL_FAM6_SANDYBRIDGE, 		core_funcs),
1848 	ICPU(INTEL_FAM6_SANDYBRIDGE_X,		core_funcs),
1849 	ICPU(INTEL_FAM6_ATOM_SILVERMONT1,	silvermont_funcs),
1850 	ICPU(INTEL_FAM6_IVYBRIDGE,		core_funcs),
1851 	ICPU(INTEL_FAM6_HASWELL_CORE,		core_funcs),
1852 	ICPU(INTEL_FAM6_BROADWELL_CORE,		core_funcs),
1853 	ICPU(INTEL_FAM6_IVYBRIDGE_X,		core_funcs),
1854 	ICPU(INTEL_FAM6_HASWELL_X,		core_funcs),
1855 	ICPU(INTEL_FAM6_HASWELL_ULT,		core_funcs),
1856 	ICPU(INTEL_FAM6_HASWELL_GT3E,		core_funcs),
1857 	ICPU(INTEL_FAM6_BROADWELL_GT3E,		core_funcs),
1858 	ICPU(INTEL_FAM6_ATOM_AIRMONT,		airmont_funcs),
1859 	ICPU(INTEL_FAM6_SKYLAKE_MOBILE,		core_funcs),
1860 	ICPU(INTEL_FAM6_BROADWELL_X,		core_funcs),
1861 	ICPU(INTEL_FAM6_SKYLAKE_DESKTOP,	core_funcs),
1862 	ICPU(INTEL_FAM6_BROADWELL_XEON_D,	core_funcs),
1863 	ICPU(INTEL_FAM6_XEON_PHI_KNL,		knl_funcs),
1864 	ICPU(INTEL_FAM6_XEON_PHI_KNM,		knl_funcs),
1865 	ICPU(INTEL_FAM6_ATOM_GOLDMONT,		bxt_funcs),
1866 	ICPU(INTEL_FAM6_ATOM_GEMINI_LAKE,       bxt_funcs),
1867 	{}
1868 };
1869 MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
1870 
1871 static const struct x86_cpu_id intel_pstate_cpu_oob_ids[] __initconst = {
1872 	ICPU(INTEL_FAM6_BROADWELL_XEON_D, core_funcs),
1873 	ICPU(INTEL_FAM6_BROADWELL_X, core_funcs),
1874 	ICPU(INTEL_FAM6_SKYLAKE_X, core_funcs),
1875 	{}
1876 };
1877 
1878 static const struct x86_cpu_id intel_pstate_cpu_ee_disable_ids[] = {
1879 	ICPU(INTEL_FAM6_KABYLAKE_DESKTOP, core_funcs),
1880 	{}
1881 };
1882 
1883 static bool pid_in_use(void);
1884 
1885 static int intel_pstate_init_cpu(unsigned int cpunum)
1886 {
1887 	struct cpudata *cpu;
1888 
1889 	cpu = all_cpu_data[cpunum];
1890 
1891 	if (!cpu) {
1892 		cpu = kzalloc(sizeof(*cpu), GFP_KERNEL);
1893 		if (!cpu)
1894 			return -ENOMEM;
1895 
1896 		all_cpu_data[cpunum] = cpu;
1897 
1898 		cpu->epp_default = -EINVAL;
1899 		cpu->epp_powersave = -EINVAL;
1900 		cpu->epp_saved = -EINVAL;
1901 	}
1902 
1903 	cpu = all_cpu_data[cpunum];
1904 
1905 	cpu->cpu = cpunum;
1906 
1907 	if (hwp_active) {
1908 		const struct x86_cpu_id *id;
1909 
1910 		id = x86_match_cpu(intel_pstate_cpu_ee_disable_ids);
1911 		if (id)
1912 			intel_pstate_disable_ee(cpunum);
1913 
1914 		intel_pstate_hwp_enable(cpu);
1915 	} else if (pid_in_use()) {
1916 		intel_pstate_pid_reset(cpu);
1917 	}
1918 
1919 	intel_pstate_get_cpu_pstates(cpu);
1920 
1921 	pr_debug("controlling: cpu %d\n", cpunum);
1922 
1923 	return 0;
1924 }
1925 
1926 static unsigned int intel_pstate_get(unsigned int cpu_num)
1927 {
1928 	struct cpudata *cpu = all_cpu_data[cpu_num];
1929 
1930 	return cpu ? get_avg_frequency(cpu) : 0;
1931 }
1932 
1933 static void intel_pstate_set_update_util_hook(unsigned int cpu_num)
1934 {
1935 	struct cpudata *cpu = all_cpu_data[cpu_num];
1936 
1937 	if (cpu->update_util_set)
1938 		return;
1939 
1940 	/* Prevent intel_pstate_update_util() from using stale data. */
1941 	cpu->sample.time = 0;
1942 	cpufreq_add_update_util_hook(cpu_num, &cpu->update_util,
1943 				     pstate_funcs.update_util);
1944 	cpu->update_util_set = true;
1945 }
1946 
1947 static void intel_pstate_clear_update_util_hook(unsigned int cpu)
1948 {
1949 	struct cpudata *cpu_data = all_cpu_data[cpu];
1950 
1951 	if (!cpu_data->update_util_set)
1952 		return;
1953 
1954 	cpufreq_remove_update_util_hook(cpu);
1955 	cpu_data->update_util_set = false;
1956 	synchronize_sched();
1957 }
1958 
1959 static int intel_pstate_get_max_freq(struct cpudata *cpu)
1960 {
1961 	return global.turbo_disabled || global.no_turbo ?
1962 			cpu->pstate.max_freq : cpu->pstate.turbo_freq;
1963 }
1964 
1965 static void intel_pstate_update_perf_limits(struct cpufreq_policy *policy,
1966 					    struct cpudata *cpu)
1967 {
1968 	int max_freq = intel_pstate_get_max_freq(cpu);
1969 	int32_t max_policy_perf, min_policy_perf;
1970 
1971 	max_policy_perf = div_ext_fp(policy->max, max_freq);
1972 	max_policy_perf = clamp_t(int32_t, max_policy_perf, 0, int_ext_tofp(1));
1973 	if (policy->max == policy->min) {
1974 		min_policy_perf = max_policy_perf;
1975 	} else {
1976 		min_policy_perf = div_ext_fp(policy->min, max_freq);
1977 		min_policy_perf = clamp_t(int32_t, min_policy_perf,
1978 					  0, max_policy_perf);
1979 	}
1980 
1981 	/* Normalize user input to [min_perf, max_perf] */
1982 	if (per_cpu_limits) {
1983 		cpu->min_perf = min_policy_perf;
1984 		cpu->max_perf = max_policy_perf;
1985 	} else {
1986 		int32_t global_min, global_max;
1987 
1988 		/* Global limits are in percent of the maximum turbo P-state. */
1989 		global_max = percent_ext_fp(global.max_perf_pct);
1990 		global_min = percent_ext_fp(global.min_perf_pct);
1991 		if (max_freq != cpu->pstate.turbo_freq) {
1992 			int32_t turbo_factor;
1993 
1994 			turbo_factor = div_ext_fp(cpu->pstate.turbo_pstate,
1995 						  cpu->pstate.max_pstate);
1996 			global_min = mul_ext_fp(global_min, turbo_factor);
1997 			global_max = mul_ext_fp(global_max, turbo_factor);
1998 		}
1999 		global_min = clamp_t(int32_t, global_min, 0, global_max);
2000 
2001 		cpu->min_perf = max(min_policy_perf, global_min);
2002 		cpu->min_perf = min(cpu->min_perf, max_policy_perf);
2003 		cpu->max_perf = min(max_policy_perf, global_max);
2004 		cpu->max_perf = max(min_policy_perf, cpu->max_perf);
2005 
2006 		/* Make sure min_perf <= max_perf */
2007 		cpu->min_perf = min(cpu->min_perf, cpu->max_perf);
2008 	}
2009 
2010 	cpu->max_perf = round_up(cpu->max_perf, EXT_FRAC_BITS);
2011 	cpu->min_perf = round_up(cpu->min_perf, EXT_FRAC_BITS);
2012 
2013 	pr_debug("cpu:%d max_perf_pct:%d min_perf_pct:%d\n", policy->cpu,
2014 		 fp_ext_toint(cpu->max_perf * 100),
2015 		 fp_ext_toint(cpu->min_perf * 100));
2016 }
2017 
2018 static int intel_pstate_set_policy(struct cpufreq_policy *policy)
2019 {
2020 	struct cpudata *cpu;
2021 
2022 	if (!policy->cpuinfo.max_freq)
2023 		return -ENODEV;
2024 
2025 	pr_debug("set_policy cpuinfo.max %u policy->max %u\n",
2026 		 policy->cpuinfo.max_freq, policy->max);
2027 
2028 	cpu = all_cpu_data[policy->cpu];
2029 	cpu->policy = policy->policy;
2030 
2031 	mutex_lock(&intel_pstate_limits_lock);
2032 
2033 	intel_pstate_update_perf_limits(policy, cpu);
2034 
2035 	if (cpu->policy == CPUFREQ_POLICY_PERFORMANCE) {
2036 		/*
2037 		 * NOHZ_FULL CPUs need this as the governor callback may not
2038 		 * be invoked on them.
2039 		 */
2040 		intel_pstate_clear_update_util_hook(policy->cpu);
2041 		intel_pstate_max_within_limits(cpu);
2042 	}
2043 
2044 	intel_pstate_set_update_util_hook(policy->cpu);
2045 
2046 	if (hwp_active)
2047 		intel_pstate_hwp_set(policy->cpu);
2048 
2049 	mutex_unlock(&intel_pstate_limits_lock);
2050 
2051 	return 0;
2052 }
2053 
2054 static void intel_pstate_adjust_policy_max(struct cpufreq_policy *policy,
2055 					 struct cpudata *cpu)
2056 {
2057 	if (cpu->pstate.max_pstate_physical > cpu->pstate.max_pstate &&
2058 	    policy->max < policy->cpuinfo.max_freq &&
2059 	    policy->max > cpu->pstate.max_freq) {
2060 		pr_debug("policy->max > max non turbo frequency\n");
2061 		policy->max = policy->cpuinfo.max_freq;
2062 	}
2063 }
2064 
2065 static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
2066 {
2067 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2068 
2069 	update_turbo_state();
2070 	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
2071 				     intel_pstate_get_max_freq(cpu));
2072 
2073 	if (policy->policy != CPUFREQ_POLICY_POWERSAVE &&
2074 	    policy->policy != CPUFREQ_POLICY_PERFORMANCE)
2075 		return -EINVAL;
2076 
2077 	intel_pstate_adjust_policy_max(policy, cpu);
2078 
2079 	return 0;
2080 }
2081 
2082 static void intel_cpufreq_stop_cpu(struct cpufreq_policy *policy)
2083 {
2084 	intel_pstate_set_min_pstate(all_cpu_data[policy->cpu]);
2085 }
2086 
2087 static void intel_pstate_stop_cpu(struct cpufreq_policy *policy)
2088 {
2089 	pr_debug("CPU %d exiting\n", policy->cpu);
2090 
2091 	intel_pstate_clear_update_util_hook(policy->cpu);
2092 	if (hwp_active)
2093 		intel_pstate_hwp_save_state(policy);
2094 	else
2095 		intel_cpufreq_stop_cpu(policy);
2096 }
2097 
2098 static int intel_pstate_cpu_exit(struct cpufreq_policy *policy)
2099 {
2100 	intel_pstate_exit_perf_limits(policy);
2101 
2102 	policy->fast_switch_possible = false;
2103 
2104 	return 0;
2105 }
2106 
2107 static int __intel_pstate_cpu_init(struct cpufreq_policy *policy)
2108 {
2109 	struct cpudata *cpu;
2110 	int rc;
2111 
2112 	rc = intel_pstate_init_cpu(policy->cpu);
2113 	if (rc)
2114 		return rc;
2115 
2116 	cpu = all_cpu_data[policy->cpu];
2117 
2118 	cpu->max_perf = int_ext_tofp(1);
2119 	cpu->min_perf = 0;
2120 
2121 	policy->min = cpu->pstate.min_pstate * cpu->pstate.scaling;
2122 	policy->max = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
2123 
2124 	/* cpuinfo and default policy values */
2125 	policy->cpuinfo.min_freq = cpu->pstate.min_pstate * cpu->pstate.scaling;
2126 	update_turbo_state();
2127 	policy->cpuinfo.max_freq = global.turbo_disabled ?
2128 			cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
2129 	policy->cpuinfo.max_freq *= cpu->pstate.scaling;
2130 
2131 	intel_pstate_init_acpi_perf_limits(policy);
2132 	cpumask_set_cpu(policy->cpu, policy->cpus);
2133 
2134 	policy->fast_switch_possible = true;
2135 
2136 	return 0;
2137 }
2138 
2139 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
2140 {
2141 	int ret = __intel_pstate_cpu_init(policy);
2142 
2143 	if (ret)
2144 		return ret;
2145 
2146 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
2147 	if (IS_ENABLED(CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE))
2148 		policy->policy = CPUFREQ_POLICY_PERFORMANCE;
2149 	else
2150 		policy->policy = CPUFREQ_POLICY_POWERSAVE;
2151 
2152 	return 0;
2153 }
2154 
2155 static struct cpufreq_driver intel_pstate = {
2156 	.flags		= CPUFREQ_CONST_LOOPS,
2157 	.verify		= intel_pstate_verify_policy,
2158 	.setpolicy	= intel_pstate_set_policy,
2159 	.suspend	= intel_pstate_hwp_save_state,
2160 	.resume		= intel_pstate_resume,
2161 	.get		= intel_pstate_get,
2162 	.init		= intel_pstate_cpu_init,
2163 	.exit		= intel_pstate_cpu_exit,
2164 	.stop_cpu	= intel_pstate_stop_cpu,
2165 	.name		= "intel_pstate",
2166 };
2167 
2168 static int intel_cpufreq_verify_policy(struct cpufreq_policy *policy)
2169 {
2170 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2171 
2172 	update_turbo_state();
2173 	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
2174 				     intel_pstate_get_max_freq(cpu));
2175 
2176 	intel_pstate_adjust_policy_max(policy, cpu);
2177 
2178 	intel_pstate_update_perf_limits(policy, cpu);
2179 
2180 	return 0;
2181 }
2182 
2183 static int intel_cpufreq_target(struct cpufreq_policy *policy,
2184 				unsigned int target_freq,
2185 				unsigned int relation)
2186 {
2187 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2188 	struct cpufreq_freqs freqs;
2189 	int target_pstate;
2190 
2191 	update_turbo_state();
2192 
2193 	freqs.old = policy->cur;
2194 	freqs.new = target_freq;
2195 
2196 	cpufreq_freq_transition_begin(policy, &freqs);
2197 	switch (relation) {
2198 	case CPUFREQ_RELATION_L:
2199 		target_pstate = DIV_ROUND_UP(freqs.new, cpu->pstate.scaling);
2200 		break;
2201 	case CPUFREQ_RELATION_H:
2202 		target_pstate = freqs.new / cpu->pstate.scaling;
2203 		break;
2204 	default:
2205 		target_pstate = DIV_ROUND_CLOSEST(freqs.new, cpu->pstate.scaling);
2206 		break;
2207 	}
2208 	target_pstate = intel_pstate_prepare_request(cpu, target_pstate);
2209 	if (target_pstate != cpu->pstate.current_pstate) {
2210 		cpu->pstate.current_pstate = target_pstate;
2211 		wrmsrl_on_cpu(policy->cpu, MSR_IA32_PERF_CTL,
2212 			      pstate_funcs.get_val(cpu, target_pstate));
2213 	}
2214 	freqs.new = target_pstate * cpu->pstate.scaling;
2215 	cpufreq_freq_transition_end(policy, &freqs, false);
2216 
2217 	return 0;
2218 }
2219 
2220 static unsigned int intel_cpufreq_fast_switch(struct cpufreq_policy *policy,
2221 					      unsigned int target_freq)
2222 {
2223 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2224 	int target_pstate;
2225 
2226 	update_turbo_state();
2227 
2228 	target_pstate = DIV_ROUND_UP(target_freq, cpu->pstate.scaling);
2229 	target_pstate = intel_pstate_prepare_request(cpu, target_pstate);
2230 	intel_pstate_update_pstate(cpu, target_pstate);
2231 	return target_pstate * cpu->pstate.scaling;
2232 }
2233 
2234 static int intel_cpufreq_cpu_init(struct cpufreq_policy *policy)
2235 {
2236 	int ret = __intel_pstate_cpu_init(policy);
2237 
2238 	if (ret)
2239 		return ret;
2240 
2241 	policy->cpuinfo.transition_latency = INTEL_CPUFREQ_TRANSITION_LATENCY;
2242 	policy->transition_delay_us = INTEL_CPUFREQ_TRANSITION_DELAY;
2243 	/* This reflects the intel_pstate_get_cpu_pstates() setting. */
2244 	policy->cur = policy->cpuinfo.min_freq;
2245 
2246 	return 0;
2247 }
2248 
2249 static struct cpufreq_driver intel_cpufreq = {
2250 	.flags		= CPUFREQ_CONST_LOOPS,
2251 	.verify		= intel_cpufreq_verify_policy,
2252 	.target		= intel_cpufreq_target,
2253 	.fast_switch	= intel_cpufreq_fast_switch,
2254 	.init		= intel_cpufreq_cpu_init,
2255 	.exit		= intel_pstate_cpu_exit,
2256 	.stop_cpu	= intel_cpufreq_stop_cpu,
2257 	.name		= "intel_cpufreq",
2258 };
2259 
2260 static struct cpufreq_driver *default_driver = &intel_pstate;
2261 
2262 static bool pid_in_use(void)
2263 {
2264 	return intel_pstate_driver == &intel_pstate &&
2265 		pstate_funcs.update_util == intel_pstate_update_util_pid;
2266 }
2267 
2268 static void intel_pstate_driver_cleanup(void)
2269 {
2270 	unsigned int cpu;
2271 
2272 	get_online_cpus();
2273 	for_each_online_cpu(cpu) {
2274 		if (all_cpu_data[cpu]) {
2275 			if (intel_pstate_driver == &intel_pstate)
2276 				intel_pstate_clear_update_util_hook(cpu);
2277 
2278 			kfree(all_cpu_data[cpu]);
2279 			all_cpu_data[cpu] = NULL;
2280 		}
2281 	}
2282 	put_online_cpus();
2283 	intel_pstate_driver = NULL;
2284 }
2285 
2286 static int intel_pstate_register_driver(struct cpufreq_driver *driver)
2287 {
2288 	int ret;
2289 
2290 	memset(&global, 0, sizeof(global));
2291 	global.max_perf_pct = 100;
2292 
2293 	intel_pstate_driver = driver;
2294 	ret = cpufreq_register_driver(intel_pstate_driver);
2295 	if (ret) {
2296 		intel_pstate_driver_cleanup();
2297 		return ret;
2298 	}
2299 
2300 	global.min_perf_pct = min_perf_pct_min();
2301 
2302 	if (pid_in_use())
2303 		intel_pstate_debug_expose_params();
2304 
2305 	return 0;
2306 }
2307 
2308 static int intel_pstate_unregister_driver(void)
2309 {
2310 	if (hwp_active)
2311 		return -EBUSY;
2312 
2313 	if (pid_in_use())
2314 		intel_pstate_debug_hide_params();
2315 
2316 	cpufreq_unregister_driver(intel_pstate_driver);
2317 	intel_pstate_driver_cleanup();
2318 
2319 	return 0;
2320 }
2321 
2322 static ssize_t intel_pstate_show_status(char *buf)
2323 {
2324 	if (!intel_pstate_driver)
2325 		return sprintf(buf, "off\n");
2326 
2327 	return sprintf(buf, "%s\n", intel_pstate_driver == &intel_pstate ?
2328 					"active" : "passive");
2329 }
2330 
2331 static int intel_pstate_update_status(const char *buf, size_t size)
2332 {
2333 	int ret;
2334 
2335 	if (size == 3 && !strncmp(buf, "off", size))
2336 		return intel_pstate_driver ?
2337 			intel_pstate_unregister_driver() : -EINVAL;
2338 
2339 	if (size == 6 && !strncmp(buf, "active", size)) {
2340 		if (intel_pstate_driver) {
2341 			if (intel_pstate_driver == &intel_pstate)
2342 				return 0;
2343 
2344 			ret = intel_pstate_unregister_driver();
2345 			if (ret)
2346 				return ret;
2347 		}
2348 
2349 		return intel_pstate_register_driver(&intel_pstate);
2350 	}
2351 
2352 	if (size == 7 && !strncmp(buf, "passive", size)) {
2353 		if (intel_pstate_driver) {
2354 			if (intel_pstate_driver == &intel_cpufreq)
2355 				return 0;
2356 
2357 			ret = intel_pstate_unregister_driver();
2358 			if (ret)
2359 				return ret;
2360 		}
2361 
2362 		return intel_pstate_register_driver(&intel_cpufreq);
2363 	}
2364 
2365 	return -EINVAL;
2366 }
2367 
2368 static int no_load __initdata;
2369 static int no_hwp __initdata;
2370 static int hwp_only __initdata;
2371 static unsigned int force_load __initdata;
2372 
2373 static int __init intel_pstate_msrs_not_valid(void)
2374 {
2375 	if (!pstate_funcs.get_max() ||
2376 	    !pstate_funcs.get_min() ||
2377 	    !pstate_funcs.get_turbo())
2378 		return -ENODEV;
2379 
2380 	return 0;
2381 }
2382 
2383 #ifdef CONFIG_ACPI
2384 static void intel_pstate_use_acpi_profile(void)
2385 {
2386 	switch (acpi_gbl_FADT.preferred_profile) {
2387 	case PM_MOBILE:
2388 	case PM_TABLET:
2389 	case PM_APPLIANCE_PC:
2390 	case PM_DESKTOP:
2391 	case PM_WORKSTATION:
2392 		pstate_funcs.update_util = intel_pstate_update_util;
2393 	}
2394 }
2395 #else
2396 static void intel_pstate_use_acpi_profile(void)
2397 {
2398 }
2399 #endif
2400 
2401 static void __init copy_cpu_funcs(struct pstate_funcs *funcs)
2402 {
2403 	pstate_funcs.get_max   = funcs->get_max;
2404 	pstate_funcs.get_max_physical = funcs->get_max_physical;
2405 	pstate_funcs.get_min   = funcs->get_min;
2406 	pstate_funcs.get_turbo = funcs->get_turbo;
2407 	pstate_funcs.get_scaling = funcs->get_scaling;
2408 	pstate_funcs.get_val   = funcs->get_val;
2409 	pstate_funcs.get_vid   = funcs->get_vid;
2410 	pstate_funcs.update_util = funcs->update_util;
2411 
2412 	intel_pstate_use_acpi_profile();
2413 }
2414 
2415 #ifdef CONFIG_ACPI
2416 
2417 static bool __init intel_pstate_no_acpi_pss(void)
2418 {
2419 	int i;
2420 
2421 	for_each_possible_cpu(i) {
2422 		acpi_status status;
2423 		union acpi_object *pss;
2424 		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
2425 		struct acpi_processor *pr = per_cpu(processors, i);
2426 
2427 		if (!pr)
2428 			continue;
2429 
2430 		status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
2431 		if (ACPI_FAILURE(status))
2432 			continue;
2433 
2434 		pss = buffer.pointer;
2435 		if (pss && pss->type == ACPI_TYPE_PACKAGE) {
2436 			kfree(pss);
2437 			return false;
2438 		}
2439 
2440 		kfree(pss);
2441 	}
2442 
2443 	return true;
2444 }
2445 
2446 static bool __init intel_pstate_has_acpi_ppc(void)
2447 {
2448 	int i;
2449 
2450 	for_each_possible_cpu(i) {
2451 		struct acpi_processor *pr = per_cpu(processors, i);
2452 
2453 		if (!pr)
2454 			continue;
2455 		if (acpi_has_method(pr->handle, "_PPC"))
2456 			return true;
2457 	}
2458 	return false;
2459 }
2460 
2461 enum {
2462 	PSS,
2463 	PPC,
2464 };
2465 
2466 struct hw_vendor_info {
2467 	u16  valid;
2468 	char oem_id[ACPI_OEM_ID_SIZE];
2469 	char oem_table_id[ACPI_OEM_TABLE_ID_SIZE];
2470 	int  oem_pwr_table;
2471 };
2472 
2473 /* Hardware vendor-specific info that has its own power management modes */
2474 static struct hw_vendor_info vendor_info[] __initdata = {
2475 	{1, "HP    ", "ProLiant", PSS},
2476 	{1, "ORACLE", "X4-2    ", PPC},
2477 	{1, "ORACLE", "X4-2L   ", PPC},
2478 	{1, "ORACLE", "X4-2B   ", PPC},
2479 	{1, "ORACLE", "X3-2    ", PPC},
2480 	{1, "ORACLE", "X3-2L   ", PPC},
2481 	{1, "ORACLE", "X3-2B   ", PPC},
2482 	{1, "ORACLE", "X4470M2 ", PPC},
2483 	{1, "ORACLE", "X4270M3 ", PPC},
2484 	{1, "ORACLE", "X4270M2 ", PPC},
2485 	{1, "ORACLE", "X4170M2 ", PPC},
2486 	{1, "ORACLE", "X4170 M3", PPC},
2487 	{1, "ORACLE", "X4275 M3", PPC},
2488 	{1, "ORACLE", "X6-2    ", PPC},
2489 	{1, "ORACLE", "Sudbury ", PPC},
2490 	{0, "", ""},
2491 };
2492 
2493 static bool __init intel_pstate_platform_pwr_mgmt_exists(void)
2494 {
2495 	struct acpi_table_header hdr;
2496 	struct hw_vendor_info *v_info;
2497 	const struct x86_cpu_id *id;
2498 	u64 misc_pwr;
2499 
2500 	id = x86_match_cpu(intel_pstate_cpu_oob_ids);
2501 	if (id) {
2502 		rdmsrl(MSR_MISC_PWR_MGMT, misc_pwr);
2503 		if ( misc_pwr & (1 << 8))
2504 			return true;
2505 	}
2506 
2507 	if (acpi_disabled ||
2508 	    ACPI_FAILURE(acpi_get_table_header(ACPI_SIG_FADT, 0, &hdr)))
2509 		return false;
2510 
2511 	for (v_info = vendor_info; v_info->valid; v_info++) {
2512 		if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) &&
2513 			!strncmp(hdr.oem_table_id, v_info->oem_table_id,
2514 						ACPI_OEM_TABLE_ID_SIZE))
2515 			switch (v_info->oem_pwr_table) {
2516 			case PSS:
2517 				return intel_pstate_no_acpi_pss();
2518 			case PPC:
2519 				return intel_pstate_has_acpi_ppc() &&
2520 					(!force_load);
2521 			}
2522 	}
2523 
2524 	return false;
2525 }
2526 
2527 static void intel_pstate_request_control_from_smm(void)
2528 {
2529 	/*
2530 	 * It may be unsafe to request P-states control from SMM if _PPC support
2531 	 * has not been enabled.
2532 	 */
2533 	if (acpi_ppc)
2534 		acpi_processor_pstate_control();
2535 }
2536 #else /* CONFIG_ACPI not enabled */
2537 static inline bool intel_pstate_platform_pwr_mgmt_exists(void) { return false; }
2538 static inline bool intel_pstate_has_acpi_ppc(void) { return false; }
2539 static inline void intel_pstate_request_control_from_smm(void) {}
2540 #endif /* CONFIG_ACPI */
2541 
2542 static const struct x86_cpu_id hwp_support_ids[] __initconst = {
2543 	{ X86_VENDOR_INTEL, 6, X86_MODEL_ANY, X86_FEATURE_HWP },
2544 	{}
2545 };
2546 
2547 static int __init intel_pstate_init(void)
2548 {
2549 	int rc;
2550 
2551 	if (no_load)
2552 		return -ENODEV;
2553 
2554 	if (x86_match_cpu(hwp_support_ids)) {
2555 		copy_cpu_funcs(&core_funcs);
2556 		if (no_hwp) {
2557 			pstate_funcs.update_util = intel_pstate_update_util;
2558 		} else {
2559 			hwp_active++;
2560 			intel_pstate.attr = hwp_cpufreq_attrs;
2561 			pstate_funcs.update_util = intel_pstate_update_util_hwp;
2562 			goto hwp_cpu_matched;
2563 		}
2564 	} else {
2565 		const struct x86_cpu_id *id;
2566 
2567 		id = x86_match_cpu(intel_pstate_cpu_ids);
2568 		if (!id)
2569 			return -ENODEV;
2570 
2571 		copy_cpu_funcs((struct pstate_funcs *)id->driver_data);
2572 	}
2573 
2574 	if (intel_pstate_msrs_not_valid())
2575 		return -ENODEV;
2576 
2577 hwp_cpu_matched:
2578 	/*
2579 	 * The Intel pstate driver will be ignored if the platform
2580 	 * firmware has its own power management modes.
2581 	 */
2582 	if (intel_pstate_platform_pwr_mgmt_exists())
2583 		return -ENODEV;
2584 
2585 	if (!hwp_active && hwp_only)
2586 		return -ENOTSUPP;
2587 
2588 	pr_info("Intel P-state driver initializing\n");
2589 
2590 	all_cpu_data = vzalloc(sizeof(void *) * num_possible_cpus());
2591 	if (!all_cpu_data)
2592 		return -ENOMEM;
2593 
2594 	intel_pstate_request_control_from_smm();
2595 
2596 	intel_pstate_sysfs_expose_params();
2597 
2598 	mutex_lock(&intel_pstate_driver_lock);
2599 	rc = intel_pstate_register_driver(default_driver);
2600 	mutex_unlock(&intel_pstate_driver_lock);
2601 	if (rc)
2602 		return rc;
2603 
2604 	if (hwp_active)
2605 		pr_info("HWP enabled\n");
2606 
2607 	return 0;
2608 }
2609 device_initcall(intel_pstate_init);
2610 
2611 static int __init intel_pstate_setup(char *str)
2612 {
2613 	if (!str)
2614 		return -EINVAL;
2615 
2616 	if (!strcmp(str, "disable")) {
2617 		no_load = 1;
2618 	} else if (!strcmp(str, "passive")) {
2619 		pr_info("Passive mode enabled\n");
2620 		default_driver = &intel_cpufreq;
2621 		no_hwp = 1;
2622 	}
2623 	if (!strcmp(str, "no_hwp")) {
2624 		pr_info("HWP disabled\n");
2625 		no_hwp = 1;
2626 	}
2627 	if (!strcmp(str, "force"))
2628 		force_load = 1;
2629 	if (!strcmp(str, "hwp_only"))
2630 		hwp_only = 1;
2631 	if (!strcmp(str, "per_cpu_perf_limits"))
2632 		per_cpu_limits = true;
2633 
2634 #ifdef CONFIG_ACPI
2635 	if (!strcmp(str, "support_acpi_ppc"))
2636 		acpi_ppc = true;
2637 #endif
2638 
2639 	return 0;
2640 }
2641 early_param("intel_pstate", intel_pstate_setup);
2642 
2643 MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>");
2644 MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors");
2645 MODULE_LICENSE("GPL");
2646