xref: /linux/drivers/cpufreq/intel_pstate.c (revision 0b8061c340b643e01da431dd60c75a41bb1d31ec)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * intel_pstate.c: Native P state management for Intel processors
4  *
5  * (C) Copyright 2012 Intel Corporation
6  * Author: Dirk Brandewie <dirk.j.brandewie@intel.com>
7  */
8 
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10 
11 #include <linux/kernel.h>
12 #include <linux/kernel_stat.h>
13 #include <linux/module.h>
14 #include <linux/ktime.h>
15 #include <linux/hrtimer.h>
16 #include <linux/tick.h>
17 #include <linux/slab.h>
18 #include <linux/sched/cpufreq.h>
19 #include <linux/list.h>
20 #include <linux/cpu.h>
21 #include <linux/cpufreq.h>
22 #include <linux/sysfs.h>
23 #include <linux/types.h>
24 #include <linux/fs.h>
25 #include <linux/acpi.h>
26 #include <linux/vmalloc.h>
27 #include <linux/pm_qos.h>
28 #include <trace/events/power.h>
29 
30 #include <asm/div64.h>
31 #include <asm/msr.h>
32 #include <asm/cpu_device_id.h>
33 #include <asm/cpufeature.h>
34 #include <asm/intel-family.h>
35 
36 #define INTEL_PSTATE_SAMPLING_INTERVAL	(10 * NSEC_PER_MSEC)
37 
38 #define INTEL_CPUFREQ_TRANSITION_LATENCY	20000
39 #define INTEL_CPUFREQ_TRANSITION_DELAY_HWP	5000
40 #define INTEL_CPUFREQ_TRANSITION_DELAY		500
41 
42 #ifdef CONFIG_ACPI
43 #include <acpi/processor.h>
44 #include <acpi/cppc_acpi.h>
45 #endif
46 
47 #define FRAC_BITS 8
48 #define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
49 #define fp_toint(X) ((X) >> FRAC_BITS)
50 
51 #define ONE_EIGHTH_FP ((int64_t)1 << (FRAC_BITS - 3))
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 u64 mul_ext_fp(u64 x, u64 y)
80 {
81 	return (x * y) >> EXT_FRAC_BITS;
82 }
83 
84 static inline u64 div_ext_fp(u64 x, u64 y)
85 {
86 	return div64_u64(x << EXT_FRAC_BITS, y);
87 }
88 
89 /**
90  * struct sample -	Store performance sample
91  * @core_avg_perf:	Ratio of APERF/MPERF which is the actual average
92  *			performance during last sample period
93  * @busy_scaled:	Scaled busy value which is used to calculate next
94  *			P state. This can be different than core_avg_perf
95  *			to account for cpu idle period
96  * @aperf:		Difference of actual performance frequency clock count
97  *			read from APERF MSR between last and current sample
98  * @mperf:		Difference of maximum performance frequency clock count
99  *			read from MPERF MSR between last and current sample
100  * @tsc:		Difference of time stamp counter between last and
101  *			current sample
102  * @time:		Current time from scheduler
103  *
104  * This structure is used in the cpudata structure to store performance sample
105  * data for choosing next P State.
106  */
107 struct sample {
108 	int32_t core_avg_perf;
109 	int32_t busy_scaled;
110 	u64 aperf;
111 	u64 mperf;
112 	u64 tsc;
113 	u64 time;
114 };
115 
116 /**
117  * struct pstate_data - Store P state data
118  * @current_pstate:	Current requested P state
119  * @min_pstate:		Min P state possible for this platform
120  * @max_pstate:		Max P state possible for this platform
121  * @max_pstate_physical:This is physical Max P state for a processor
122  *			This can be higher than the max_pstate which can
123  *			be limited by platform thermal design power limits
124  * @scaling:		Scaling factor to  convert frequency to cpufreq
125  *			frequency units
126  * @turbo_pstate:	Max Turbo P state possible for this platform
127  * @max_freq:		@max_pstate frequency in cpufreq units
128  * @turbo_freq:		@turbo_pstate frequency in cpufreq units
129  *
130  * Stores the per cpu model P state limits and current P state.
131  */
132 struct pstate_data {
133 	int	current_pstate;
134 	int	min_pstate;
135 	int	max_pstate;
136 	int	max_pstate_physical;
137 	int	scaling;
138 	int	turbo_pstate;
139 	unsigned int max_freq;
140 	unsigned int turbo_freq;
141 };
142 
143 /**
144  * struct vid_data -	Stores voltage information data
145  * @min:		VID data for this platform corresponding to
146  *			the lowest P state
147  * @max:		VID data corresponding to the highest P State.
148  * @turbo:		VID data for turbo P state
149  * @ratio:		Ratio of (vid max - vid min) /
150  *			(max P state - Min P State)
151  *
152  * Stores the voltage data for DVFS (Dynamic Voltage and Frequency Scaling)
153  * This data is used in Atom platforms, where in addition to target P state,
154  * the voltage data needs to be specified to select next P State.
155  */
156 struct vid_data {
157 	int min;
158 	int max;
159 	int turbo;
160 	int32_t ratio;
161 };
162 
163 /**
164  * struct global_params - Global parameters, mostly tunable via sysfs.
165  * @no_turbo:		Whether or not to use turbo P-states.
166  * @turbo_disabled:	Whether or not turbo P-states are available at all,
167  *			based on the MSR_IA32_MISC_ENABLE value and whether or
168  *			not the maximum reported turbo P-state is different from
169  *			the maximum reported non-turbo one.
170  * @turbo_disabled_mf:	The @turbo_disabled value reflected by cpuinfo.max_freq.
171  * @min_perf_pct:	Minimum capacity limit in percent of the maximum turbo
172  *			P-state capacity.
173  * @max_perf_pct:	Maximum capacity limit in percent of the maximum turbo
174  *			P-state capacity.
175  */
176 struct global_params {
177 	bool no_turbo;
178 	bool turbo_disabled;
179 	bool turbo_disabled_mf;
180 	int max_perf_pct;
181 	int min_perf_pct;
182 };
183 
184 /**
185  * struct cpudata -	Per CPU instance data storage
186  * @cpu:		CPU number for this instance data
187  * @policy:		CPUFreq policy value
188  * @update_util:	CPUFreq utility callback information
189  * @update_util_set:	CPUFreq utility callback is set
190  * @iowait_boost:	iowait-related boost fraction
191  * @last_update:	Time of the last update.
192  * @pstate:		Stores P state limits for this CPU
193  * @vid:		Stores VID limits for this CPU
194  * @last_sample_time:	Last Sample time
195  * @aperf_mperf_shift:	APERF vs MPERF counting frequency difference
196  * @prev_aperf:		Last APERF value read from APERF MSR
197  * @prev_mperf:		Last MPERF value read from MPERF MSR
198  * @prev_tsc:		Last timestamp counter (TSC) value
199  * @prev_cummulative_iowait: IO Wait time difference from last and
200  *			current sample
201  * @sample:		Storage for storing last Sample data
202  * @min_perf_ratio:	Minimum capacity in terms of PERF or HWP ratios
203  * @max_perf_ratio:	Maximum capacity in terms of PERF or HWP ratios
204  * @acpi_perf_data:	Stores ACPI perf information read from _PSS
205  * @valid_pss_table:	Set to true for valid ACPI _PSS entries found
206  * @epp_powersave:	Last saved HWP energy performance preference
207  *			(EPP) or energy performance bias (EPB),
208  *			when policy switched to performance
209  * @epp_policy:		Last saved policy used to set EPP/EPB
210  * @epp_default:	Power on default HWP energy performance
211  *			preference/bias
212  * @epp_cached		Cached HWP energy-performance preference value
213  * @hwp_req_cached:	Cached value of the last HWP Request MSR
214  * @hwp_cap_cached:	Cached value of the last HWP Capabilities MSR
215  * @last_io_update:	Last time when IO wake flag was set
216  * @sched_flags:	Store scheduler flags for possible cross CPU update
217  * @hwp_boost_min:	Last HWP boosted min performance
218  * @suspended:		Whether or not the driver has been suspended.
219  *
220  * This structure stores per CPU instance data for all CPUs.
221  */
222 struct cpudata {
223 	int cpu;
224 
225 	unsigned int policy;
226 	struct update_util_data update_util;
227 	bool   update_util_set;
228 
229 	struct pstate_data pstate;
230 	struct vid_data vid;
231 
232 	u64	last_update;
233 	u64	last_sample_time;
234 	u64	aperf_mperf_shift;
235 	u64	prev_aperf;
236 	u64	prev_mperf;
237 	u64	prev_tsc;
238 	u64	prev_cummulative_iowait;
239 	struct sample sample;
240 	int32_t	min_perf_ratio;
241 	int32_t	max_perf_ratio;
242 #ifdef CONFIG_ACPI
243 	struct acpi_processor_performance acpi_perf_data;
244 	bool valid_pss_table;
245 #endif
246 	unsigned int iowait_boost;
247 	s16 epp_powersave;
248 	s16 epp_policy;
249 	s16 epp_default;
250 	s16 epp_cached;
251 	u64 hwp_req_cached;
252 	u64 hwp_cap_cached;
253 	u64 last_io_update;
254 	unsigned int sched_flags;
255 	u32 hwp_boost_min;
256 	bool suspended;
257 };
258 
259 static struct cpudata **all_cpu_data;
260 
261 /**
262  * struct pstate_funcs - Per CPU model specific callbacks
263  * @get_max:		Callback to get maximum non turbo effective P state
264  * @get_max_physical:	Callback to get maximum non turbo physical P state
265  * @get_min:		Callback to get minimum P state
266  * @get_turbo:		Callback to get turbo P state
267  * @get_scaling:	Callback to get frequency scaling factor
268  * @get_aperf_mperf_shift: Callback to get the APERF vs MPERF frequency difference
269  * @get_val:		Callback to convert P state to actual MSR write value
270  * @get_vid:		Callback to get VID data for Atom platforms
271  *
272  * Core and Atom CPU models have different way to get P State limits. This
273  * structure is used to store those callbacks.
274  */
275 struct pstate_funcs {
276 	int (*get_max)(void);
277 	int (*get_max_physical)(void);
278 	int (*get_min)(void);
279 	int (*get_turbo)(void);
280 	int (*get_scaling)(void);
281 	int (*get_aperf_mperf_shift)(void);
282 	u64 (*get_val)(struct cpudata*, int pstate);
283 	void (*get_vid)(struct cpudata *);
284 };
285 
286 static struct pstate_funcs pstate_funcs __read_mostly;
287 
288 static int hwp_active __read_mostly;
289 static int hwp_mode_bdw __read_mostly;
290 static bool per_cpu_limits __read_mostly;
291 static bool hwp_boost __read_mostly;
292 
293 static struct cpufreq_driver *intel_pstate_driver __read_mostly;
294 
295 #ifdef CONFIG_ACPI
296 static bool acpi_ppc;
297 #endif
298 
299 static struct global_params global;
300 
301 static DEFINE_MUTEX(intel_pstate_driver_lock);
302 static DEFINE_MUTEX(intel_pstate_limits_lock);
303 
304 #ifdef CONFIG_ACPI
305 
306 static bool intel_pstate_acpi_pm_profile_server(void)
307 {
308 	if (acpi_gbl_FADT.preferred_profile == PM_ENTERPRISE_SERVER ||
309 	    acpi_gbl_FADT.preferred_profile == PM_PERFORMANCE_SERVER)
310 		return true;
311 
312 	return false;
313 }
314 
315 static bool intel_pstate_get_ppc_enable_status(void)
316 {
317 	if (intel_pstate_acpi_pm_profile_server())
318 		return true;
319 
320 	return acpi_ppc;
321 }
322 
323 #ifdef CONFIG_ACPI_CPPC_LIB
324 
325 /* The work item is needed to avoid CPU hotplug locking issues */
326 static void intel_pstste_sched_itmt_work_fn(struct work_struct *work)
327 {
328 	sched_set_itmt_support();
329 }
330 
331 static DECLARE_WORK(sched_itmt_work, intel_pstste_sched_itmt_work_fn);
332 
333 static void intel_pstate_set_itmt_prio(int cpu)
334 {
335 	struct cppc_perf_caps cppc_perf;
336 	static u32 max_highest_perf = 0, min_highest_perf = U32_MAX;
337 	int ret;
338 
339 	ret = cppc_get_perf_caps(cpu, &cppc_perf);
340 	if (ret)
341 		return;
342 
343 	/*
344 	 * The priorities can be set regardless of whether or not
345 	 * sched_set_itmt_support(true) has been called and it is valid to
346 	 * update them at any time after it has been called.
347 	 */
348 	sched_set_itmt_core_prio(cppc_perf.highest_perf, cpu);
349 
350 	if (max_highest_perf <= min_highest_perf) {
351 		if (cppc_perf.highest_perf > max_highest_perf)
352 			max_highest_perf = cppc_perf.highest_perf;
353 
354 		if (cppc_perf.highest_perf < min_highest_perf)
355 			min_highest_perf = cppc_perf.highest_perf;
356 
357 		if (max_highest_perf > min_highest_perf) {
358 			/*
359 			 * This code can be run during CPU online under the
360 			 * CPU hotplug locks, so sched_set_itmt_support()
361 			 * cannot be called from here.  Queue up a work item
362 			 * to invoke it.
363 			 */
364 			schedule_work(&sched_itmt_work);
365 		}
366 	}
367 }
368 
369 static int intel_pstate_get_cppc_guranteed(int cpu)
370 {
371 	struct cppc_perf_caps cppc_perf;
372 	int ret;
373 
374 	ret = cppc_get_perf_caps(cpu, &cppc_perf);
375 	if (ret)
376 		return ret;
377 
378 	if (cppc_perf.guaranteed_perf)
379 		return cppc_perf.guaranteed_perf;
380 
381 	return cppc_perf.nominal_perf;
382 }
383 
384 #else /* CONFIG_ACPI_CPPC_LIB */
385 static void intel_pstate_set_itmt_prio(int cpu)
386 {
387 }
388 #endif /* CONFIG_ACPI_CPPC_LIB */
389 
390 static void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy)
391 {
392 	struct cpudata *cpu;
393 	int ret;
394 	int i;
395 
396 	if (hwp_active) {
397 		intel_pstate_set_itmt_prio(policy->cpu);
398 		return;
399 	}
400 
401 	if (!intel_pstate_get_ppc_enable_status())
402 		return;
403 
404 	cpu = all_cpu_data[policy->cpu];
405 
406 	ret = acpi_processor_register_performance(&cpu->acpi_perf_data,
407 						  policy->cpu);
408 	if (ret)
409 		return;
410 
411 	/*
412 	 * Check if the control value in _PSS is for PERF_CTL MSR, which should
413 	 * guarantee that the states returned by it map to the states in our
414 	 * list directly.
415 	 */
416 	if (cpu->acpi_perf_data.control_register.space_id !=
417 						ACPI_ADR_SPACE_FIXED_HARDWARE)
418 		goto err;
419 
420 	/*
421 	 * If there is only one entry _PSS, simply ignore _PSS and continue as
422 	 * usual without taking _PSS into account
423 	 */
424 	if (cpu->acpi_perf_data.state_count < 2)
425 		goto err;
426 
427 	pr_debug("CPU%u - ACPI _PSS perf data\n", policy->cpu);
428 	for (i = 0; i < cpu->acpi_perf_data.state_count; i++) {
429 		pr_debug("     %cP%d: %u MHz, %u mW, 0x%x\n",
430 			 (i == cpu->acpi_perf_data.state ? '*' : ' '), i,
431 			 (u32) cpu->acpi_perf_data.states[i].core_frequency,
432 			 (u32) cpu->acpi_perf_data.states[i].power,
433 			 (u32) cpu->acpi_perf_data.states[i].control);
434 	}
435 
436 	/*
437 	 * The _PSS table doesn't contain whole turbo frequency range.
438 	 * This just contains +1 MHZ above the max non turbo frequency,
439 	 * with control value corresponding to max turbo ratio. But
440 	 * when cpufreq set policy is called, it will call with this
441 	 * max frequency, which will cause a reduced performance as
442 	 * this driver uses real max turbo frequency as the max
443 	 * frequency. So correct this frequency in _PSS table to
444 	 * correct max turbo frequency based on the turbo state.
445 	 * Also need to convert to MHz as _PSS freq is in MHz.
446 	 */
447 	if (!global.turbo_disabled)
448 		cpu->acpi_perf_data.states[0].core_frequency =
449 					policy->cpuinfo.max_freq / 1000;
450 	cpu->valid_pss_table = true;
451 	pr_debug("_PPC limits will be enforced\n");
452 
453 	return;
454 
455  err:
456 	cpu->valid_pss_table = false;
457 	acpi_processor_unregister_performance(policy->cpu);
458 }
459 
460 static void intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
461 {
462 	struct cpudata *cpu;
463 
464 	cpu = all_cpu_data[policy->cpu];
465 	if (!cpu->valid_pss_table)
466 		return;
467 
468 	acpi_processor_unregister_performance(policy->cpu);
469 }
470 #else /* CONFIG_ACPI */
471 static inline void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy)
472 {
473 }
474 
475 static inline void intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
476 {
477 }
478 
479 static inline bool intel_pstate_acpi_pm_profile_server(void)
480 {
481 	return false;
482 }
483 #endif /* CONFIG_ACPI */
484 
485 #ifndef CONFIG_ACPI_CPPC_LIB
486 static int intel_pstate_get_cppc_guranteed(int cpu)
487 {
488 	return -ENOTSUPP;
489 }
490 #endif /* CONFIG_ACPI_CPPC_LIB */
491 
492 static inline void update_turbo_state(void)
493 {
494 	u64 misc_en;
495 	struct cpudata *cpu;
496 
497 	cpu = all_cpu_data[0];
498 	rdmsrl(MSR_IA32_MISC_ENABLE, misc_en);
499 	global.turbo_disabled =
500 		(misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE ||
501 		 cpu->pstate.max_pstate == cpu->pstate.turbo_pstate);
502 }
503 
504 static int min_perf_pct_min(void)
505 {
506 	struct cpudata *cpu = all_cpu_data[0];
507 	int turbo_pstate = cpu->pstate.turbo_pstate;
508 
509 	return turbo_pstate ?
510 		(cpu->pstate.min_pstate * 100 / turbo_pstate) : 0;
511 }
512 
513 static s16 intel_pstate_get_epb(struct cpudata *cpu_data)
514 {
515 	u64 epb;
516 	int ret;
517 
518 	if (!boot_cpu_has(X86_FEATURE_EPB))
519 		return -ENXIO;
520 
521 	ret = rdmsrl_on_cpu(cpu_data->cpu, MSR_IA32_ENERGY_PERF_BIAS, &epb);
522 	if (ret)
523 		return (s16)ret;
524 
525 	return (s16)(epb & 0x0f);
526 }
527 
528 static s16 intel_pstate_get_epp(struct cpudata *cpu_data, u64 hwp_req_data)
529 {
530 	s16 epp;
531 
532 	if (boot_cpu_has(X86_FEATURE_HWP_EPP)) {
533 		/*
534 		 * When hwp_req_data is 0, means that caller didn't read
535 		 * MSR_HWP_REQUEST, so need to read and get EPP.
536 		 */
537 		if (!hwp_req_data) {
538 			epp = rdmsrl_on_cpu(cpu_data->cpu, MSR_HWP_REQUEST,
539 					    &hwp_req_data);
540 			if (epp)
541 				return epp;
542 		}
543 		epp = (hwp_req_data >> 24) & 0xff;
544 	} else {
545 		/* When there is no EPP present, HWP uses EPB settings */
546 		epp = intel_pstate_get_epb(cpu_data);
547 	}
548 
549 	return epp;
550 }
551 
552 static int intel_pstate_set_epb(int cpu, s16 pref)
553 {
554 	u64 epb;
555 	int ret;
556 
557 	if (!boot_cpu_has(X86_FEATURE_EPB))
558 		return -ENXIO;
559 
560 	ret = rdmsrl_on_cpu(cpu, MSR_IA32_ENERGY_PERF_BIAS, &epb);
561 	if (ret)
562 		return ret;
563 
564 	epb = (epb & ~0x0f) | pref;
565 	wrmsrl_on_cpu(cpu, MSR_IA32_ENERGY_PERF_BIAS, epb);
566 
567 	return 0;
568 }
569 
570 /*
571  * EPP/EPB display strings corresponding to EPP index in the
572  * energy_perf_strings[]
573  *	index		String
574  *-------------------------------------
575  *	0		default
576  *	1		performance
577  *	2		balance_performance
578  *	3		balance_power
579  *	4		power
580  */
581 static const char * const energy_perf_strings[] = {
582 	"default",
583 	"performance",
584 	"balance_performance",
585 	"balance_power",
586 	"power",
587 	NULL
588 };
589 static const unsigned int epp_values[] = {
590 	HWP_EPP_PERFORMANCE,
591 	HWP_EPP_BALANCE_PERFORMANCE,
592 	HWP_EPP_BALANCE_POWERSAVE,
593 	HWP_EPP_POWERSAVE
594 };
595 
596 static int intel_pstate_get_energy_pref_index(struct cpudata *cpu_data, int *raw_epp)
597 {
598 	s16 epp;
599 	int index = -EINVAL;
600 
601 	*raw_epp = 0;
602 	epp = intel_pstate_get_epp(cpu_data, 0);
603 	if (epp < 0)
604 		return epp;
605 
606 	if (boot_cpu_has(X86_FEATURE_HWP_EPP)) {
607 		if (epp == HWP_EPP_PERFORMANCE)
608 			return 1;
609 		if (epp == HWP_EPP_BALANCE_PERFORMANCE)
610 			return 2;
611 		if (epp == HWP_EPP_BALANCE_POWERSAVE)
612 			return 3;
613 		if (epp == HWP_EPP_POWERSAVE)
614 			return 4;
615 		*raw_epp = epp;
616 		return 0;
617 	} else if (boot_cpu_has(X86_FEATURE_EPB)) {
618 		/*
619 		 * Range:
620 		 *	0x00-0x03	:	Performance
621 		 *	0x04-0x07	:	Balance performance
622 		 *	0x08-0x0B	:	Balance power
623 		 *	0x0C-0x0F	:	Power
624 		 * The EPB is a 4 bit value, but our ranges restrict the
625 		 * value which can be set. Here only using top two bits
626 		 * effectively.
627 		 */
628 		index = (epp >> 2) + 1;
629 	}
630 
631 	return index;
632 }
633 
634 static int intel_pstate_set_epp(struct cpudata *cpu, u32 epp)
635 {
636 	int ret;
637 
638 	/*
639 	 * Use the cached HWP Request MSR value, because in the active mode the
640 	 * register itself may be updated by intel_pstate_hwp_boost_up() or
641 	 * intel_pstate_hwp_boost_down() at any time.
642 	 */
643 	u64 value = READ_ONCE(cpu->hwp_req_cached);
644 
645 	value &= ~GENMASK_ULL(31, 24);
646 	value |= (u64)epp << 24;
647 	/*
648 	 * The only other updater of hwp_req_cached in the active mode,
649 	 * intel_pstate_hwp_set(), is called under the same lock as this
650 	 * function, so it cannot run in parallel with the update below.
651 	 */
652 	WRITE_ONCE(cpu->hwp_req_cached, value);
653 	ret = wrmsrl_on_cpu(cpu->cpu, MSR_HWP_REQUEST, value);
654 	if (!ret)
655 		cpu->epp_cached = epp;
656 
657 	return ret;
658 }
659 
660 static int intel_pstate_set_energy_pref_index(struct cpudata *cpu_data,
661 					      int pref_index, bool use_raw,
662 					      u32 raw_epp)
663 {
664 	int epp = -EINVAL;
665 	int ret;
666 
667 	if (!pref_index)
668 		epp = cpu_data->epp_default;
669 
670 	if (boot_cpu_has(X86_FEATURE_HWP_EPP)) {
671 		if (use_raw)
672 			epp = raw_epp;
673 		else if (epp == -EINVAL)
674 			epp = epp_values[pref_index - 1];
675 
676 		/*
677 		 * To avoid confusion, refuse to set EPP to any values different
678 		 * from 0 (performance) if the current policy is "performance",
679 		 * because those values would be overridden.
680 		 */
681 		if (epp > 0 && cpu_data->policy == CPUFREQ_POLICY_PERFORMANCE)
682 			return -EBUSY;
683 
684 		ret = intel_pstate_set_epp(cpu_data, epp);
685 	} else {
686 		if (epp == -EINVAL)
687 			epp = (pref_index - 1) << 2;
688 		ret = intel_pstate_set_epb(cpu_data->cpu, epp);
689 	}
690 
691 	return ret;
692 }
693 
694 static ssize_t show_energy_performance_available_preferences(
695 				struct cpufreq_policy *policy, char *buf)
696 {
697 	int i = 0;
698 	int ret = 0;
699 
700 	while (energy_perf_strings[i] != NULL)
701 		ret += sprintf(&buf[ret], "%s ", energy_perf_strings[i++]);
702 
703 	ret += sprintf(&buf[ret], "\n");
704 
705 	return ret;
706 }
707 
708 cpufreq_freq_attr_ro(energy_performance_available_preferences);
709 
710 static struct cpufreq_driver intel_pstate;
711 
712 static ssize_t store_energy_performance_preference(
713 		struct cpufreq_policy *policy, const char *buf, size_t count)
714 {
715 	struct cpudata *cpu = all_cpu_data[policy->cpu];
716 	char str_preference[21];
717 	bool raw = false;
718 	ssize_t ret;
719 	u32 epp = 0;
720 
721 	ret = sscanf(buf, "%20s", str_preference);
722 	if (ret != 1)
723 		return -EINVAL;
724 
725 	ret = match_string(energy_perf_strings, -1, str_preference);
726 	if (ret < 0) {
727 		if (!boot_cpu_has(X86_FEATURE_HWP_EPP))
728 			return ret;
729 
730 		ret = kstrtouint(buf, 10, &epp);
731 		if (ret)
732 			return ret;
733 
734 		if (epp > 255)
735 			return -EINVAL;
736 
737 		raw = true;
738 	}
739 
740 	/*
741 	 * This function runs with the policy R/W semaphore held, which
742 	 * guarantees that the driver pointer will not change while it is
743 	 * running.
744 	 */
745 	if (!intel_pstate_driver)
746 		return -EAGAIN;
747 
748 	mutex_lock(&intel_pstate_limits_lock);
749 
750 	if (intel_pstate_driver == &intel_pstate) {
751 		ret = intel_pstate_set_energy_pref_index(cpu, ret, raw, epp);
752 	} else {
753 		/*
754 		 * In the passive mode the governor needs to be stopped on the
755 		 * target CPU before the EPP update and restarted after it,
756 		 * which is super-heavy-weight, so make sure it is worth doing
757 		 * upfront.
758 		 */
759 		if (!raw)
760 			epp = ret ? epp_values[ret - 1] : cpu->epp_default;
761 
762 		if (cpu->epp_cached != epp) {
763 			int err;
764 
765 			cpufreq_stop_governor(policy);
766 			ret = intel_pstate_set_epp(cpu, epp);
767 			err = cpufreq_start_governor(policy);
768 			if (!ret)
769 				ret = err;
770 		}
771 	}
772 
773 	mutex_unlock(&intel_pstate_limits_lock);
774 
775 	return ret ?: count;
776 }
777 
778 static ssize_t show_energy_performance_preference(
779 				struct cpufreq_policy *policy, char *buf)
780 {
781 	struct cpudata *cpu_data = all_cpu_data[policy->cpu];
782 	int preference, raw_epp;
783 
784 	preference = intel_pstate_get_energy_pref_index(cpu_data, &raw_epp);
785 	if (preference < 0)
786 		return preference;
787 
788 	if (raw_epp)
789 		return  sprintf(buf, "%d\n", raw_epp);
790 	else
791 		return  sprintf(buf, "%s\n", energy_perf_strings[preference]);
792 }
793 
794 cpufreq_freq_attr_rw(energy_performance_preference);
795 
796 static ssize_t show_base_frequency(struct cpufreq_policy *policy, char *buf)
797 {
798 	struct cpudata *cpu;
799 	u64 cap;
800 	int ratio;
801 
802 	ratio = intel_pstate_get_cppc_guranteed(policy->cpu);
803 	if (ratio <= 0) {
804 		rdmsrl_on_cpu(policy->cpu, MSR_HWP_CAPABILITIES, &cap);
805 		ratio = HWP_GUARANTEED_PERF(cap);
806 	}
807 
808 	cpu = all_cpu_data[policy->cpu];
809 
810 	return sprintf(buf, "%d\n", ratio * cpu->pstate.scaling);
811 }
812 
813 cpufreq_freq_attr_ro(base_frequency);
814 
815 static struct freq_attr *hwp_cpufreq_attrs[] = {
816 	&energy_performance_preference,
817 	&energy_performance_available_preferences,
818 	&base_frequency,
819 	NULL,
820 };
821 
822 static void intel_pstate_get_hwp_max(struct cpudata *cpu, int *phy_max,
823 				     int *current_max)
824 {
825 	u64 cap;
826 
827 	rdmsrl_on_cpu(cpu->cpu, MSR_HWP_CAPABILITIES, &cap);
828 	WRITE_ONCE(cpu->hwp_cap_cached, cap);
829 	if (global.no_turbo || global.turbo_disabled)
830 		*current_max = HWP_GUARANTEED_PERF(cap);
831 	else
832 		*current_max = HWP_HIGHEST_PERF(cap);
833 
834 	*phy_max = HWP_HIGHEST_PERF(cap);
835 }
836 
837 static void intel_pstate_hwp_set(unsigned int cpu)
838 {
839 	struct cpudata *cpu_data = all_cpu_data[cpu];
840 	int max, min;
841 	u64 value;
842 	s16 epp;
843 
844 	max = cpu_data->max_perf_ratio;
845 	min = cpu_data->min_perf_ratio;
846 
847 	if (cpu_data->policy == CPUFREQ_POLICY_PERFORMANCE)
848 		min = max;
849 
850 	rdmsrl_on_cpu(cpu, MSR_HWP_REQUEST, &value);
851 
852 	value &= ~HWP_MIN_PERF(~0L);
853 	value |= HWP_MIN_PERF(min);
854 
855 	value &= ~HWP_MAX_PERF(~0L);
856 	value |= HWP_MAX_PERF(max);
857 
858 	if (cpu_data->epp_policy == cpu_data->policy)
859 		goto skip_epp;
860 
861 	cpu_data->epp_policy = cpu_data->policy;
862 
863 	if (cpu_data->policy == CPUFREQ_POLICY_PERFORMANCE) {
864 		epp = intel_pstate_get_epp(cpu_data, value);
865 		cpu_data->epp_powersave = epp;
866 		/* If EPP read was failed, then don't try to write */
867 		if (epp < 0)
868 			goto skip_epp;
869 
870 		epp = 0;
871 	} else {
872 		/* skip setting EPP, when saved value is invalid */
873 		if (cpu_data->epp_powersave < 0)
874 			goto skip_epp;
875 
876 		/*
877 		 * No need to restore EPP when it is not zero. This
878 		 * means:
879 		 *  - Policy is not changed
880 		 *  - user has manually changed
881 		 *  - Error reading EPB
882 		 */
883 		epp = intel_pstate_get_epp(cpu_data, value);
884 		if (epp)
885 			goto skip_epp;
886 
887 		epp = cpu_data->epp_powersave;
888 	}
889 	if (boot_cpu_has(X86_FEATURE_HWP_EPP)) {
890 		value &= ~GENMASK_ULL(31, 24);
891 		value |= (u64)epp << 24;
892 	} else {
893 		intel_pstate_set_epb(cpu, epp);
894 	}
895 skip_epp:
896 	WRITE_ONCE(cpu_data->hwp_req_cached, value);
897 	wrmsrl_on_cpu(cpu, MSR_HWP_REQUEST, value);
898 }
899 
900 static void intel_pstate_hwp_offline(struct cpudata *cpu)
901 {
902 	u64 value = READ_ONCE(cpu->hwp_req_cached);
903 	int min_perf;
904 
905 	if (boot_cpu_has(X86_FEATURE_HWP_EPP)) {
906 		/*
907 		 * In case the EPP has been set to "performance" by the
908 		 * active mode "performance" scaling algorithm, replace that
909 		 * temporary value with the cached EPP one.
910 		 */
911 		value &= ~GENMASK_ULL(31, 24);
912 		value |= HWP_ENERGY_PERF_PREFERENCE(cpu->epp_cached);
913 		WRITE_ONCE(cpu->hwp_req_cached, value);
914 	}
915 
916 	value &= ~GENMASK_ULL(31, 0);
917 	min_perf = HWP_LOWEST_PERF(READ_ONCE(cpu->hwp_cap_cached));
918 
919 	/* Set hwp_max = hwp_min */
920 	value |= HWP_MAX_PERF(min_perf);
921 	value |= HWP_MIN_PERF(min_perf);
922 
923 	/* Set EPP to min */
924 	if (boot_cpu_has(X86_FEATURE_HWP_EPP))
925 		value |= HWP_ENERGY_PERF_PREFERENCE(HWP_EPP_POWERSAVE);
926 
927 	wrmsrl_on_cpu(cpu->cpu, MSR_HWP_REQUEST, value);
928 }
929 
930 #define POWER_CTL_EE_ENABLE	1
931 #define POWER_CTL_EE_DISABLE	2
932 
933 static int power_ctl_ee_state;
934 
935 static void set_power_ctl_ee_state(bool input)
936 {
937 	u64 power_ctl;
938 
939 	mutex_lock(&intel_pstate_driver_lock);
940 	rdmsrl(MSR_IA32_POWER_CTL, power_ctl);
941 	if (input) {
942 		power_ctl &= ~BIT(MSR_IA32_POWER_CTL_BIT_EE);
943 		power_ctl_ee_state = POWER_CTL_EE_ENABLE;
944 	} else {
945 		power_ctl |= BIT(MSR_IA32_POWER_CTL_BIT_EE);
946 		power_ctl_ee_state = POWER_CTL_EE_DISABLE;
947 	}
948 	wrmsrl(MSR_IA32_POWER_CTL, power_ctl);
949 	mutex_unlock(&intel_pstate_driver_lock);
950 }
951 
952 static void intel_pstate_hwp_enable(struct cpudata *cpudata);
953 
954 static void intel_pstate_hwp_reenable(struct cpudata *cpu)
955 {
956 	intel_pstate_hwp_enable(cpu);
957 	wrmsrl_on_cpu(cpu->cpu, MSR_HWP_REQUEST, READ_ONCE(cpu->hwp_req_cached));
958 }
959 
960 static int intel_pstate_suspend(struct cpufreq_policy *policy)
961 {
962 	struct cpudata *cpu = all_cpu_data[policy->cpu];
963 
964 	pr_debug("CPU %d suspending\n", cpu->cpu);
965 
966 	cpu->suspended = true;
967 
968 	return 0;
969 }
970 
971 static int intel_pstate_resume(struct cpufreq_policy *policy)
972 {
973 	struct cpudata *cpu = all_cpu_data[policy->cpu];
974 
975 	pr_debug("CPU %d resuming\n", cpu->cpu);
976 
977 	/* Only restore if the system default is changed */
978 	if (power_ctl_ee_state == POWER_CTL_EE_ENABLE)
979 		set_power_ctl_ee_state(true);
980 	else if (power_ctl_ee_state == POWER_CTL_EE_DISABLE)
981 		set_power_ctl_ee_state(false);
982 
983 	if (cpu->suspended && hwp_active) {
984 		mutex_lock(&intel_pstate_limits_lock);
985 
986 		/* Re-enable HWP, because "online" has not done that. */
987 		intel_pstate_hwp_reenable(cpu);
988 
989 		mutex_unlock(&intel_pstate_limits_lock);
990 	}
991 
992 	cpu->suspended = false;
993 
994 	return 0;
995 }
996 
997 static void intel_pstate_update_policies(void)
998 {
999 	int cpu;
1000 
1001 	for_each_possible_cpu(cpu)
1002 		cpufreq_update_policy(cpu);
1003 }
1004 
1005 static void intel_pstate_update_max_freq(unsigned int cpu)
1006 {
1007 	struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu);
1008 	struct cpudata *cpudata;
1009 
1010 	if (!policy)
1011 		return;
1012 
1013 	cpudata = all_cpu_data[cpu];
1014 	policy->cpuinfo.max_freq = global.turbo_disabled_mf ?
1015 			cpudata->pstate.max_freq : cpudata->pstate.turbo_freq;
1016 
1017 	refresh_frequency_limits(policy);
1018 
1019 	cpufreq_cpu_release(policy);
1020 }
1021 
1022 static void intel_pstate_update_limits(unsigned int cpu)
1023 {
1024 	mutex_lock(&intel_pstate_driver_lock);
1025 
1026 	update_turbo_state();
1027 	/*
1028 	 * If turbo has been turned on or off globally, policy limits for
1029 	 * all CPUs need to be updated to reflect that.
1030 	 */
1031 	if (global.turbo_disabled_mf != global.turbo_disabled) {
1032 		global.turbo_disabled_mf = global.turbo_disabled;
1033 		arch_set_max_freq_ratio(global.turbo_disabled);
1034 		for_each_possible_cpu(cpu)
1035 			intel_pstate_update_max_freq(cpu);
1036 	} else {
1037 		cpufreq_update_policy(cpu);
1038 	}
1039 
1040 	mutex_unlock(&intel_pstate_driver_lock);
1041 }
1042 
1043 /************************** sysfs begin ************************/
1044 #define show_one(file_name, object)					\
1045 	static ssize_t show_##file_name					\
1046 	(struct kobject *kobj, struct kobj_attribute *attr, char *buf)	\
1047 	{								\
1048 		return sprintf(buf, "%u\n", global.object);		\
1049 	}
1050 
1051 static ssize_t intel_pstate_show_status(char *buf);
1052 static int intel_pstate_update_status(const char *buf, size_t size);
1053 
1054 static ssize_t show_status(struct kobject *kobj,
1055 			   struct kobj_attribute *attr, char *buf)
1056 {
1057 	ssize_t ret;
1058 
1059 	mutex_lock(&intel_pstate_driver_lock);
1060 	ret = intel_pstate_show_status(buf);
1061 	mutex_unlock(&intel_pstate_driver_lock);
1062 
1063 	return ret;
1064 }
1065 
1066 static ssize_t store_status(struct kobject *a, struct kobj_attribute *b,
1067 			    const char *buf, size_t count)
1068 {
1069 	char *p = memchr(buf, '\n', count);
1070 	int ret;
1071 
1072 	mutex_lock(&intel_pstate_driver_lock);
1073 	ret = intel_pstate_update_status(buf, p ? p - buf : count);
1074 	mutex_unlock(&intel_pstate_driver_lock);
1075 
1076 	return ret < 0 ? ret : count;
1077 }
1078 
1079 static ssize_t show_turbo_pct(struct kobject *kobj,
1080 				struct kobj_attribute *attr, char *buf)
1081 {
1082 	struct cpudata *cpu;
1083 	int total, no_turbo, turbo_pct;
1084 	uint32_t turbo_fp;
1085 
1086 	mutex_lock(&intel_pstate_driver_lock);
1087 
1088 	if (!intel_pstate_driver) {
1089 		mutex_unlock(&intel_pstate_driver_lock);
1090 		return -EAGAIN;
1091 	}
1092 
1093 	cpu = all_cpu_data[0];
1094 
1095 	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
1096 	no_turbo = cpu->pstate.max_pstate - cpu->pstate.min_pstate + 1;
1097 	turbo_fp = div_fp(no_turbo, total);
1098 	turbo_pct = 100 - fp_toint(mul_fp(turbo_fp, int_tofp(100)));
1099 
1100 	mutex_unlock(&intel_pstate_driver_lock);
1101 
1102 	return sprintf(buf, "%u\n", turbo_pct);
1103 }
1104 
1105 static ssize_t show_num_pstates(struct kobject *kobj,
1106 				struct kobj_attribute *attr, char *buf)
1107 {
1108 	struct cpudata *cpu;
1109 	int total;
1110 
1111 	mutex_lock(&intel_pstate_driver_lock);
1112 
1113 	if (!intel_pstate_driver) {
1114 		mutex_unlock(&intel_pstate_driver_lock);
1115 		return -EAGAIN;
1116 	}
1117 
1118 	cpu = all_cpu_data[0];
1119 	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
1120 
1121 	mutex_unlock(&intel_pstate_driver_lock);
1122 
1123 	return sprintf(buf, "%u\n", total);
1124 }
1125 
1126 static ssize_t show_no_turbo(struct kobject *kobj,
1127 			     struct kobj_attribute *attr, char *buf)
1128 {
1129 	ssize_t ret;
1130 
1131 	mutex_lock(&intel_pstate_driver_lock);
1132 
1133 	if (!intel_pstate_driver) {
1134 		mutex_unlock(&intel_pstate_driver_lock);
1135 		return -EAGAIN;
1136 	}
1137 
1138 	update_turbo_state();
1139 	if (global.turbo_disabled)
1140 		ret = sprintf(buf, "%u\n", global.turbo_disabled);
1141 	else
1142 		ret = sprintf(buf, "%u\n", global.no_turbo);
1143 
1144 	mutex_unlock(&intel_pstate_driver_lock);
1145 
1146 	return ret;
1147 }
1148 
1149 static ssize_t store_no_turbo(struct kobject *a, struct kobj_attribute *b,
1150 			      const char *buf, size_t count)
1151 {
1152 	unsigned int input;
1153 	int ret;
1154 
1155 	ret = sscanf(buf, "%u", &input);
1156 	if (ret != 1)
1157 		return -EINVAL;
1158 
1159 	mutex_lock(&intel_pstate_driver_lock);
1160 
1161 	if (!intel_pstate_driver) {
1162 		mutex_unlock(&intel_pstate_driver_lock);
1163 		return -EAGAIN;
1164 	}
1165 
1166 	mutex_lock(&intel_pstate_limits_lock);
1167 
1168 	update_turbo_state();
1169 	if (global.turbo_disabled) {
1170 		pr_notice_once("Turbo disabled by BIOS or unavailable on processor\n");
1171 		mutex_unlock(&intel_pstate_limits_lock);
1172 		mutex_unlock(&intel_pstate_driver_lock);
1173 		return -EPERM;
1174 	}
1175 
1176 	global.no_turbo = clamp_t(int, input, 0, 1);
1177 
1178 	if (global.no_turbo) {
1179 		struct cpudata *cpu = all_cpu_data[0];
1180 		int pct = cpu->pstate.max_pstate * 100 / cpu->pstate.turbo_pstate;
1181 
1182 		/* Squash the global minimum into the permitted range. */
1183 		if (global.min_perf_pct > pct)
1184 			global.min_perf_pct = pct;
1185 	}
1186 
1187 	mutex_unlock(&intel_pstate_limits_lock);
1188 
1189 	intel_pstate_update_policies();
1190 
1191 	mutex_unlock(&intel_pstate_driver_lock);
1192 
1193 	return count;
1194 }
1195 
1196 static void update_qos_request(enum freq_qos_req_type type)
1197 {
1198 	int max_state, turbo_max, freq, i, perf_pct;
1199 	struct freq_qos_request *req;
1200 	struct cpufreq_policy *policy;
1201 
1202 	for_each_possible_cpu(i) {
1203 		struct cpudata *cpu = all_cpu_data[i];
1204 
1205 		policy = cpufreq_cpu_get(i);
1206 		if (!policy)
1207 			continue;
1208 
1209 		req = policy->driver_data;
1210 		cpufreq_cpu_put(policy);
1211 
1212 		if (!req)
1213 			continue;
1214 
1215 		if (hwp_active)
1216 			intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state);
1217 		else
1218 			turbo_max = cpu->pstate.turbo_pstate;
1219 
1220 		if (type == FREQ_QOS_MIN) {
1221 			perf_pct = global.min_perf_pct;
1222 		} else {
1223 			req++;
1224 			perf_pct = global.max_perf_pct;
1225 		}
1226 
1227 		freq = DIV_ROUND_UP(turbo_max * perf_pct, 100);
1228 		freq *= cpu->pstate.scaling;
1229 
1230 		if (freq_qos_update_request(req, freq) < 0)
1231 			pr_warn("Failed to update freq constraint: CPU%d\n", i);
1232 	}
1233 }
1234 
1235 static ssize_t store_max_perf_pct(struct kobject *a, struct kobj_attribute *b,
1236 				  const char *buf, size_t count)
1237 {
1238 	unsigned int input;
1239 	int ret;
1240 
1241 	ret = sscanf(buf, "%u", &input);
1242 	if (ret != 1)
1243 		return -EINVAL;
1244 
1245 	mutex_lock(&intel_pstate_driver_lock);
1246 
1247 	if (!intel_pstate_driver) {
1248 		mutex_unlock(&intel_pstate_driver_lock);
1249 		return -EAGAIN;
1250 	}
1251 
1252 	mutex_lock(&intel_pstate_limits_lock);
1253 
1254 	global.max_perf_pct = clamp_t(int, input, global.min_perf_pct, 100);
1255 
1256 	mutex_unlock(&intel_pstate_limits_lock);
1257 
1258 	if (intel_pstate_driver == &intel_pstate)
1259 		intel_pstate_update_policies();
1260 	else
1261 		update_qos_request(FREQ_QOS_MAX);
1262 
1263 	mutex_unlock(&intel_pstate_driver_lock);
1264 
1265 	return count;
1266 }
1267 
1268 static ssize_t store_min_perf_pct(struct kobject *a, struct kobj_attribute *b,
1269 				  const char *buf, size_t count)
1270 {
1271 	unsigned int input;
1272 	int ret;
1273 
1274 	ret = sscanf(buf, "%u", &input);
1275 	if (ret != 1)
1276 		return -EINVAL;
1277 
1278 	mutex_lock(&intel_pstate_driver_lock);
1279 
1280 	if (!intel_pstate_driver) {
1281 		mutex_unlock(&intel_pstate_driver_lock);
1282 		return -EAGAIN;
1283 	}
1284 
1285 	mutex_lock(&intel_pstate_limits_lock);
1286 
1287 	global.min_perf_pct = clamp_t(int, input,
1288 				      min_perf_pct_min(), global.max_perf_pct);
1289 
1290 	mutex_unlock(&intel_pstate_limits_lock);
1291 
1292 	if (intel_pstate_driver == &intel_pstate)
1293 		intel_pstate_update_policies();
1294 	else
1295 		update_qos_request(FREQ_QOS_MIN);
1296 
1297 	mutex_unlock(&intel_pstate_driver_lock);
1298 
1299 	return count;
1300 }
1301 
1302 static ssize_t show_hwp_dynamic_boost(struct kobject *kobj,
1303 				struct kobj_attribute *attr, char *buf)
1304 {
1305 	return sprintf(buf, "%u\n", hwp_boost);
1306 }
1307 
1308 static ssize_t store_hwp_dynamic_boost(struct kobject *a,
1309 				       struct kobj_attribute *b,
1310 				       const char *buf, size_t count)
1311 {
1312 	unsigned int input;
1313 	int ret;
1314 
1315 	ret = kstrtouint(buf, 10, &input);
1316 	if (ret)
1317 		return ret;
1318 
1319 	mutex_lock(&intel_pstate_driver_lock);
1320 	hwp_boost = !!input;
1321 	intel_pstate_update_policies();
1322 	mutex_unlock(&intel_pstate_driver_lock);
1323 
1324 	return count;
1325 }
1326 
1327 static ssize_t show_energy_efficiency(struct kobject *kobj, struct kobj_attribute *attr,
1328 				      char *buf)
1329 {
1330 	u64 power_ctl;
1331 	int enable;
1332 
1333 	rdmsrl(MSR_IA32_POWER_CTL, power_ctl);
1334 	enable = !!(power_ctl & BIT(MSR_IA32_POWER_CTL_BIT_EE));
1335 	return sprintf(buf, "%d\n", !enable);
1336 }
1337 
1338 static ssize_t store_energy_efficiency(struct kobject *a, struct kobj_attribute *b,
1339 				       const char *buf, size_t count)
1340 {
1341 	bool input;
1342 	int ret;
1343 
1344 	ret = kstrtobool(buf, &input);
1345 	if (ret)
1346 		return ret;
1347 
1348 	set_power_ctl_ee_state(input);
1349 
1350 	return count;
1351 }
1352 
1353 show_one(max_perf_pct, max_perf_pct);
1354 show_one(min_perf_pct, min_perf_pct);
1355 
1356 define_one_global_rw(status);
1357 define_one_global_rw(no_turbo);
1358 define_one_global_rw(max_perf_pct);
1359 define_one_global_rw(min_perf_pct);
1360 define_one_global_ro(turbo_pct);
1361 define_one_global_ro(num_pstates);
1362 define_one_global_rw(hwp_dynamic_boost);
1363 define_one_global_rw(energy_efficiency);
1364 
1365 static struct attribute *intel_pstate_attributes[] = {
1366 	&status.attr,
1367 	&no_turbo.attr,
1368 	&turbo_pct.attr,
1369 	&num_pstates.attr,
1370 	NULL
1371 };
1372 
1373 static const struct attribute_group intel_pstate_attr_group = {
1374 	.attrs = intel_pstate_attributes,
1375 };
1376 
1377 static const struct x86_cpu_id intel_pstate_cpu_ee_disable_ids[];
1378 
1379 static struct kobject *intel_pstate_kobject;
1380 
1381 static void __init intel_pstate_sysfs_expose_params(void)
1382 {
1383 	int rc;
1384 
1385 	intel_pstate_kobject = kobject_create_and_add("intel_pstate",
1386 						&cpu_subsys.dev_root->kobj);
1387 	if (WARN_ON(!intel_pstate_kobject))
1388 		return;
1389 
1390 	rc = sysfs_create_group(intel_pstate_kobject, &intel_pstate_attr_group);
1391 	if (WARN_ON(rc))
1392 		return;
1393 
1394 	/*
1395 	 * If per cpu limits are enforced there are no global limits, so
1396 	 * return without creating max/min_perf_pct attributes
1397 	 */
1398 	if (per_cpu_limits)
1399 		return;
1400 
1401 	rc = sysfs_create_file(intel_pstate_kobject, &max_perf_pct.attr);
1402 	WARN_ON(rc);
1403 
1404 	rc = sysfs_create_file(intel_pstate_kobject, &min_perf_pct.attr);
1405 	WARN_ON(rc);
1406 
1407 	if (x86_match_cpu(intel_pstate_cpu_ee_disable_ids)) {
1408 		rc = sysfs_create_file(intel_pstate_kobject, &energy_efficiency.attr);
1409 		WARN_ON(rc);
1410 	}
1411 }
1412 
1413 static void __init intel_pstate_sysfs_remove(void)
1414 {
1415 	if (!intel_pstate_kobject)
1416 		return;
1417 
1418 	sysfs_remove_group(intel_pstate_kobject, &intel_pstate_attr_group);
1419 
1420 	if (!per_cpu_limits) {
1421 		sysfs_remove_file(intel_pstate_kobject, &max_perf_pct.attr);
1422 		sysfs_remove_file(intel_pstate_kobject, &min_perf_pct.attr);
1423 
1424 		if (x86_match_cpu(intel_pstate_cpu_ee_disable_ids))
1425 			sysfs_remove_file(intel_pstate_kobject, &energy_efficiency.attr);
1426 	}
1427 
1428 	kobject_put(intel_pstate_kobject);
1429 }
1430 
1431 static void intel_pstate_sysfs_expose_hwp_dynamic_boost(void)
1432 {
1433 	int rc;
1434 
1435 	if (!hwp_active)
1436 		return;
1437 
1438 	rc = sysfs_create_file(intel_pstate_kobject, &hwp_dynamic_boost.attr);
1439 	WARN_ON_ONCE(rc);
1440 }
1441 
1442 static void intel_pstate_sysfs_hide_hwp_dynamic_boost(void)
1443 {
1444 	if (!hwp_active)
1445 		return;
1446 
1447 	sysfs_remove_file(intel_pstate_kobject, &hwp_dynamic_boost.attr);
1448 }
1449 
1450 /************************** sysfs end ************************/
1451 
1452 static void intel_pstate_hwp_enable(struct cpudata *cpudata)
1453 {
1454 	/* First disable HWP notification interrupt as we don't process them */
1455 	if (boot_cpu_has(X86_FEATURE_HWP_NOTIFY))
1456 		wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_INTERRUPT, 0x00);
1457 
1458 	wrmsrl_on_cpu(cpudata->cpu, MSR_PM_ENABLE, 0x1);
1459 	if (cpudata->epp_default == -EINVAL)
1460 		cpudata->epp_default = intel_pstate_get_epp(cpudata, 0);
1461 }
1462 
1463 static int atom_get_min_pstate(void)
1464 {
1465 	u64 value;
1466 
1467 	rdmsrl(MSR_ATOM_CORE_RATIOS, value);
1468 	return (value >> 8) & 0x7F;
1469 }
1470 
1471 static int atom_get_max_pstate(void)
1472 {
1473 	u64 value;
1474 
1475 	rdmsrl(MSR_ATOM_CORE_RATIOS, value);
1476 	return (value >> 16) & 0x7F;
1477 }
1478 
1479 static int atom_get_turbo_pstate(void)
1480 {
1481 	u64 value;
1482 
1483 	rdmsrl(MSR_ATOM_CORE_TURBO_RATIOS, value);
1484 	return value & 0x7F;
1485 }
1486 
1487 static u64 atom_get_val(struct cpudata *cpudata, int pstate)
1488 {
1489 	u64 val;
1490 	int32_t vid_fp;
1491 	u32 vid;
1492 
1493 	val = (u64)pstate << 8;
1494 	if (global.no_turbo && !global.turbo_disabled)
1495 		val |= (u64)1 << 32;
1496 
1497 	vid_fp = cpudata->vid.min + mul_fp(
1498 		int_tofp(pstate - cpudata->pstate.min_pstate),
1499 		cpudata->vid.ratio);
1500 
1501 	vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
1502 	vid = ceiling_fp(vid_fp);
1503 
1504 	if (pstate > cpudata->pstate.max_pstate)
1505 		vid = cpudata->vid.turbo;
1506 
1507 	return val | vid;
1508 }
1509 
1510 static int silvermont_get_scaling(void)
1511 {
1512 	u64 value;
1513 	int i;
1514 	/* Defined in Table 35-6 from SDM (Sept 2015) */
1515 	static int silvermont_freq_table[] = {
1516 		83300, 100000, 133300, 116700, 80000};
1517 
1518 	rdmsrl(MSR_FSB_FREQ, value);
1519 	i = value & 0x7;
1520 	WARN_ON(i > 4);
1521 
1522 	return silvermont_freq_table[i];
1523 }
1524 
1525 static int airmont_get_scaling(void)
1526 {
1527 	u64 value;
1528 	int i;
1529 	/* Defined in Table 35-10 from SDM (Sept 2015) */
1530 	static int airmont_freq_table[] = {
1531 		83300, 100000, 133300, 116700, 80000,
1532 		93300, 90000, 88900, 87500};
1533 
1534 	rdmsrl(MSR_FSB_FREQ, value);
1535 	i = value & 0xF;
1536 	WARN_ON(i > 8);
1537 
1538 	return airmont_freq_table[i];
1539 }
1540 
1541 static void atom_get_vid(struct cpudata *cpudata)
1542 {
1543 	u64 value;
1544 
1545 	rdmsrl(MSR_ATOM_CORE_VIDS, value);
1546 	cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
1547 	cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
1548 	cpudata->vid.ratio = div_fp(
1549 		cpudata->vid.max - cpudata->vid.min,
1550 		int_tofp(cpudata->pstate.max_pstate -
1551 			cpudata->pstate.min_pstate));
1552 
1553 	rdmsrl(MSR_ATOM_CORE_TURBO_VIDS, value);
1554 	cpudata->vid.turbo = value & 0x7f;
1555 }
1556 
1557 static int core_get_min_pstate(void)
1558 {
1559 	u64 value;
1560 
1561 	rdmsrl(MSR_PLATFORM_INFO, value);
1562 	return (value >> 40) & 0xFF;
1563 }
1564 
1565 static int core_get_max_pstate_physical(void)
1566 {
1567 	u64 value;
1568 
1569 	rdmsrl(MSR_PLATFORM_INFO, value);
1570 	return (value >> 8) & 0xFF;
1571 }
1572 
1573 static int core_get_tdp_ratio(u64 plat_info)
1574 {
1575 	/* Check how many TDP levels present */
1576 	if (plat_info & 0x600000000) {
1577 		u64 tdp_ctrl;
1578 		u64 tdp_ratio;
1579 		int tdp_msr;
1580 		int err;
1581 
1582 		/* Get the TDP level (0, 1, 2) to get ratios */
1583 		err = rdmsrl_safe(MSR_CONFIG_TDP_CONTROL, &tdp_ctrl);
1584 		if (err)
1585 			return err;
1586 
1587 		/* TDP MSR are continuous starting at 0x648 */
1588 		tdp_msr = MSR_CONFIG_TDP_NOMINAL + (tdp_ctrl & 0x03);
1589 		err = rdmsrl_safe(tdp_msr, &tdp_ratio);
1590 		if (err)
1591 			return err;
1592 
1593 		/* For level 1 and 2, bits[23:16] contain the ratio */
1594 		if (tdp_ctrl & 0x03)
1595 			tdp_ratio >>= 16;
1596 
1597 		tdp_ratio &= 0xff; /* ratios are only 8 bits long */
1598 		pr_debug("tdp_ratio %x\n", (int)tdp_ratio);
1599 
1600 		return (int)tdp_ratio;
1601 	}
1602 
1603 	return -ENXIO;
1604 }
1605 
1606 static int core_get_max_pstate(void)
1607 {
1608 	u64 tar;
1609 	u64 plat_info;
1610 	int max_pstate;
1611 	int tdp_ratio;
1612 	int err;
1613 
1614 	rdmsrl(MSR_PLATFORM_INFO, plat_info);
1615 	max_pstate = (plat_info >> 8) & 0xFF;
1616 
1617 	tdp_ratio = core_get_tdp_ratio(plat_info);
1618 	if (tdp_ratio <= 0)
1619 		return max_pstate;
1620 
1621 	if (hwp_active) {
1622 		/* Turbo activation ratio is not used on HWP platforms */
1623 		return tdp_ratio;
1624 	}
1625 
1626 	err = rdmsrl_safe(MSR_TURBO_ACTIVATION_RATIO, &tar);
1627 	if (!err) {
1628 		int tar_levels;
1629 
1630 		/* Do some sanity checking for safety */
1631 		tar_levels = tar & 0xff;
1632 		if (tdp_ratio - 1 == tar_levels) {
1633 			max_pstate = tar_levels;
1634 			pr_debug("max_pstate=TAC %x\n", max_pstate);
1635 		}
1636 	}
1637 
1638 	return max_pstate;
1639 }
1640 
1641 static int core_get_turbo_pstate(void)
1642 {
1643 	u64 value;
1644 	int nont, ret;
1645 
1646 	rdmsrl(MSR_TURBO_RATIO_LIMIT, value);
1647 	nont = core_get_max_pstate();
1648 	ret = (value) & 255;
1649 	if (ret <= nont)
1650 		ret = nont;
1651 	return ret;
1652 }
1653 
1654 static inline int core_get_scaling(void)
1655 {
1656 	return 100000;
1657 }
1658 
1659 static u64 core_get_val(struct cpudata *cpudata, int pstate)
1660 {
1661 	u64 val;
1662 
1663 	val = (u64)pstate << 8;
1664 	if (global.no_turbo && !global.turbo_disabled)
1665 		val |= (u64)1 << 32;
1666 
1667 	return val;
1668 }
1669 
1670 static int knl_get_aperf_mperf_shift(void)
1671 {
1672 	return 10;
1673 }
1674 
1675 static int knl_get_turbo_pstate(void)
1676 {
1677 	u64 value;
1678 	int nont, ret;
1679 
1680 	rdmsrl(MSR_TURBO_RATIO_LIMIT, value);
1681 	nont = core_get_max_pstate();
1682 	ret = (((value) >> 8) & 0xFF);
1683 	if (ret <= nont)
1684 		ret = nont;
1685 	return ret;
1686 }
1687 
1688 static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate)
1689 {
1690 	trace_cpu_frequency(pstate * cpu->pstate.scaling, cpu->cpu);
1691 	cpu->pstate.current_pstate = pstate;
1692 	/*
1693 	 * Generally, there is no guarantee that this code will always run on
1694 	 * the CPU being updated, so force the register update to run on the
1695 	 * right CPU.
1696 	 */
1697 	wrmsrl_on_cpu(cpu->cpu, MSR_IA32_PERF_CTL,
1698 		      pstate_funcs.get_val(cpu, pstate));
1699 }
1700 
1701 static void intel_pstate_set_min_pstate(struct cpudata *cpu)
1702 {
1703 	intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate);
1704 }
1705 
1706 static void intel_pstate_max_within_limits(struct cpudata *cpu)
1707 {
1708 	int pstate = max(cpu->pstate.min_pstate, cpu->max_perf_ratio);
1709 
1710 	update_turbo_state();
1711 	intel_pstate_set_pstate(cpu, pstate);
1712 }
1713 
1714 static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
1715 {
1716 	cpu->pstate.min_pstate = pstate_funcs.get_min();
1717 	cpu->pstate.max_pstate_physical = pstate_funcs.get_max_physical();
1718 	cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
1719 	cpu->pstate.scaling = pstate_funcs.get_scaling();
1720 
1721 	if (hwp_active && !hwp_mode_bdw) {
1722 		unsigned int phy_max, current_max;
1723 
1724 		intel_pstate_get_hwp_max(cpu, &phy_max, &current_max);
1725 		cpu->pstate.turbo_freq = phy_max * cpu->pstate.scaling;
1726 		cpu->pstate.turbo_pstate = phy_max;
1727 		cpu->pstate.max_pstate = HWP_GUARANTEED_PERF(READ_ONCE(cpu->hwp_cap_cached));
1728 	} else {
1729 		cpu->pstate.turbo_freq = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
1730 		cpu->pstate.max_pstate = pstate_funcs.get_max();
1731 	}
1732 	cpu->pstate.max_freq = cpu->pstate.max_pstate * cpu->pstate.scaling;
1733 
1734 	if (pstate_funcs.get_aperf_mperf_shift)
1735 		cpu->aperf_mperf_shift = pstate_funcs.get_aperf_mperf_shift();
1736 
1737 	if (pstate_funcs.get_vid)
1738 		pstate_funcs.get_vid(cpu);
1739 
1740 	intel_pstate_set_min_pstate(cpu);
1741 }
1742 
1743 /*
1744  * Long hold time will keep high perf limits for long time,
1745  * which negatively impacts perf/watt for some workloads,
1746  * like specpower. 3ms is based on experiements on some
1747  * workoads.
1748  */
1749 static int hwp_boost_hold_time_ns = 3 * NSEC_PER_MSEC;
1750 
1751 static inline void intel_pstate_hwp_boost_up(struct cpudata *cpu)
1752 {
1753 	u64 hwp_req = READ_ONCE(cpu->hwp_req_cached);
1754 	u64 hwp_cap = READ_ONCE(cpu->hwp_cap_cached);
1755 	u32 max_limit = (hwp_req & 0xff00) >> 8;
1756 	u32 min_limit = (hwp_req & 0xff);
1757 	u32 boost_level1;
1758 
1759 	/*
1760 	 * Cases to consider (User changes via sysfs or boot time):
1761 	 * If, P0 (Turbo max) = P1 (Guaranteed max) = min:
1762 	 *	No boost, return.
1763 	 * If, P0 (Turbo max) > P1 (Guaranteed max) = min:
1764 	 *     Should result in one level boost only for P0.
1765 	 * If, P0 (Turbo max) = P1 (Guaranteed max) > min:
1766 	 *     Should result in two level boost:
1767 	 *         (min + p1)/2 and P1.
1768 	 * If, P0 (Turbo max) > P1 (Guaranteed max) > min:
1769 	 *     Should result in three level boost:
1770 	 *        (min + p1)/2, P1 and P0.
1771 	 */
1772 
1773 	/* If max and min are equal or already at max, nothing to boost */
1774 	if (max_limit == min_limit || cpu->hwp_boost_min >= max_limit)
1775 		return;
1776 
1777 	if (!cpu->hwp_boost_min)
1778 		cpu->hwp_boost_min = min_limit;
1779 
1780 	/* level at half way mark between min and guranteed */
1781 	boost_level1 = (HWP_GUARANTEED_PERF(hwp_cap) + min_limit) >> 1;
1782 
1783 	if (cpu->hwp_boost_min < boost_level1)
1784 		cpu->hwp_boost_min = boost_level1;
1785 	else if (cpu->hwp_boost_min < HWP_GUARANTEED_PERF(hwp_cap))
1786 		cpu->hwp_boost_min = HWP_GUARANTEED_PERF(hwp_cap);
1787 	else if (cpu->hwp_boost_min == HWP_GUARANTEED_PERF(hwp_cap) &&
1788 		 max_limit != HWP_GUARANTEED_PERF(hwp_cap))
1789 		cpu->hwp_boost_min = max_limit;
1790 	else
1791 		return;
1792 
1793 	hwp_req = (hwp_req & ~GENMASK_ULL(7, 0)) | cpu->hwp_boost_min;
1794 	wrmsrl(MSR_HWP_REQUEST, hwp_req);
1795 	cpu->last_update = cpu->sample.time;
1796 }
1797 
1798 static inline void intel_pstate_hwp_boost_down(struct cpudata *cpu)
1799 {
1800 	if (cpu->hwp_boost_min) {
1801 		bool expired;
1802 
1803 		/* Check if we are idle for hold time to boost down */
1804 		expired = time_after64(cpu->sample.time, cpu->last_update +
1805 				       hwp_boost_hold_time_ns);
1806 		if (expired) {
1807 			wrmsrl(MSR_HWP_REQUEST, cpu->hwp_req_cached);
1808 			cpu->hwp_boost_min = 0;
1809 		}
1810 	}
1811 	cpu->last_update = cpu->sample.time;
1812 }
1813 
1814 static inline void intel_pstate_update_util_hwp_local(struct cpudata *cpu,
1815 						      u64 time)
1816 {
1817 	cpu->sample.time = time;
1818 
1819 	if (cpu->sched_flags & SCHED_CPUFREQ_IOWAIT) {
1820 		bool do_io = false;
1821 
1822 		cpu->sched_flags = 0;
1823 		/*
1824 		 * Set iowait_boost flag and update time. Since IO WAIT flag
1825 		 * is set all the time, we can't just conclude that there is
1826 		 * some IO bound activity is scheduled on this CPU with just
1827 		 * one occurrence. If we receive at least two in two
1828 		 * consecutive ticks, then we treat as boost candidate.
1829 		 */
1830 		if (time_before64(time, cpu->last_io_update + 2 * TICK_NSEC))
1831 			do_io = true;
1832 
1833 		cpu->last_io_update = time;
1834 
1835 		if (do_io)
1836 			intel_pstate_hwp_boost_up(cpu);
1837 
1838 	} else {
1839 		intel_pstate_hwp_boost_down(cpu);
1840 	}
1841 }
1842 
1843 static inline void intel_pstate_update_util_hwp(struct update_util_data *data,
1844 						u64 time, unsigned int flags)
1845 {
1846 	struct cpudata *cpu = container_of(data, struct cpudata, update_util);
1847 
1848 	cpu->sched_flags |= flags;
1849 
1850 	if (smp_processor_id() == cpu->cpu)
1851 		intel_pstate_update_util_hwp_local(cpu, time);
1852 }
1853 
1854 static inline void intel_pstate_calc_avg_perf(struct cpudata *cpu)
1855 {
1856 	struct sample *sample = &cpu->sample;
1857 
1858 	sample->core_avg_perf = div_ext_fp(sample->aperf, sample->mperf);
1859 }
1860 
1861 static inline bool intel_pstate_sample(struct cpudata *cpu, u64 time)
1862 {
1863 	u64 aperf, mperf;
1864 	unsigned long flags;
1865 	u64 tsc;
1866 
1867 	local_irq_save(flags);
1868 	rdmsrl(MSR_IA32_APERF, aperf);
1869 	rdmsrl(MSR_IA32_MPERF, mperf);
1870 	tsc = rdtsc();
1871 	if (cpu->prev_mperf == mperf || cpu->prev_tsc == tsc) {
1872 		local_irq_restore(flags);
1873 		return false;
1874 	}
1875 	local_irq_restore(flags);
1876 
1877 	cpu->last_sample_time = cpu->sample.time;
1878 	cpu->sample.time = time;
1879 	cpu->sample.aperf = aperf;
1880 	cpu->sample.mperf = mperf;
1881 	cpu->sample.tsc =  tsc;
1882 	cpu->sample.aperf -= cpu->prev_aperf;
1883 	cpu->sample.mperf -= cpu->prev_mperf;
1884 	cpu->sample.tsc -= cpu->prev_tsc;
1885 
1886 	cpu->prev_aperf = aperf;
1887 	cpu->prev_mperf = mperf;
1888 	cpu->prev_tsc = tsc;
1889 	/*
1890 	 * First time this function is invoked in a given cycle, all of the
1891 	 * previous sample data fields are equal to zero or stale and they must
1892 	 * be populated with meaningful numbers for things to work, so assume
1893 	 * that sample.time will always be reset before setting the utilization
1894 	 * update hook and make the caller skip the sample then.
1895 	 */
1896 	if (cpu->last_sample_time) {
1897 		intel_pstate_calc_avg_perf(cpu);
1898 		return true;
1899 	}
1900 	return false;
1901 }
1902 
1903 static inline int32_t get_avg_frequency(struct cpudata *cpu)
1904 {
1905 	return mul_ext_fp(cpu->sample.core_avg_perf, cpu_khz);
1906 }
1907 
1908 static inline int32_t get_avg_pstate(struct cpudata *cpu)
1909 {
1910 	return mul_ext_fp(cpu->pstate.max_pstate_physical,
1911 			  cpu->sample.core_avg_perf);
1912 }
1913 
1914 static inline int32_t get_target_pstate(struct cpudata *cpu)
1915 {
1916 	struct sample *sample = &cpu->sample;
1917 	int32_t busy_frac;
1918 	int target, avg_pstate;
1919 
1920 	busy_frac = div_fp(sample->mperf << cpu->aperf_mperf_shift,
1921 			   sample->tsc);
1922 
1923 	if (busy_frac < cpu->iowait_boost)
1924 		busy_frac = cpu->iowait_boost;
1925 
1926 	sample->busy_scaled = busy_frac * 100;
1927 
1928 	target = global.no_turbo || global.turbo_disabled ?
1929 			cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
1930 	target += target >> 2;
1931 	target = mul_fp(target, busy_frac);
1932 	if (target < cpu->pstate.min_pstate)
1933 		target = cpu->pstate.min_pstate;
1934 
1935 	/*
1936 	 * If the average P-state during the previous cycle was higher than the
1937 	 * current target, add 50% of the difference to the target to reduce
1938 	 * possible performance oscillations and offset possible performance
1939 	 * loss related to moving the workload from one CPU to another within
1940 	 * a package/module.
1941 	 */
1942 	avg_pstate = get_avg_pstate(cpu);
1943 	if (avg_pstate > target)
1944 		target += (avg_pstate - target) >> 1;
1945 
1946 	return target;
1947 }
1948 
1949 static int intel_pstate_prepare_request(struct cpudata *cpu, int pstate)
1950 {
1951 	int min_pstate = max(cpu->pstate.min_pstate, cpu->min_perf_ratio);
1952 	int max_pstate = max(min_pstate, cpu->max_perf_ratio);
1953 
1954 	return clamp_t(int, pstate, min_pstate, max_pstate);
1955 }
1956 
1957 static void intel_pstate_update_pstate(struct cpudata *cpu, int pstate)
1958 {
1959 	if (pstate == cpu->pstate.current_pstate)
1960 		return;
1961 
1962 	cpu->pstate.current_pstate = pstate;
1963 	wrmsrl(MSR_IA32_PERF_CTL, pstate_funcs.get_val(cpu, pstate));
1964 }
1965 
1966 static void intel_pstate_adjust_pstate(struct cpudata *cpu)
1967 {
1968 	int from = cpu->pstate.current_pstate;
1969 	struct sample *sample;
1970 	int target_pstate;
1971 
1972 	update_turbo_state();
1973 
1974 	target_pstate = get_target_pstate(cpu);
1975 	target_pstate = intel_pstate_prepare_request(cpu, target_pstate);
1976 	trace_cpu_frequency(target_pstate * cpu->pstate.scaling, cpu->cpu);
1977 	intel_pstate_update_pstate(cpu, target_pstate);
1978 
1979 	sample = &cpu->sample;
1980 	trace_pstate_sample(mul_ext_fp(100, sample->core_avg_perf),
1981 		fp_toint(sample->busy_scaled),
1982 		from,
1983 		cpu->pstate.current_pstate,
1984 		sample->mperf,
1985 		sample->aperf,
1986 		sample->tsc,
1987 		get_avg_frequency(cpu),
1988 		fp_toint(cpu->iowait_boost * 100));
1989 }
1990 
1991 static void intel_pstate_update_util(struct update_util_data *data, u64 time,
1992 				     unsigned int flags)
1993 {
1994 	struct cpudata *cpu = container_of(data, struct cpudata, update_util);
1995 	u64 delta_ns;
1996 
1997 	/* Don't allow remote callbacks */
1998 	if (smp_processor_id() != cpu->cpu)
1999 		return;
2000 
2001 	delta_ns = time - cpu->last_update;
2002 	if (flags & SCHED_CPUFREQ_IOWAIT) {
2003 		/* Start over if the CPU may have been idle. */
2004 		if (delta_ns > TICK_NSEC) {
2005 			cpu->iowait_boost = ONE_EIGHTH_FP;
2006 		} else if (cpu->iowait_boost >= ONE_EIGHTH_FP) {
2007 			cpu->iowait_boost <<= 1;
2008 			if (cpu->iowait_boost > int_tofp(1))
2009 				cpu->iowait_boost = int_tofp(1);
2010 		} else {
2011 			cpu->iowait_boost = ONE_EIGHTH_FP;
2012 		}
2013 	} else if (cpu->iowait_boost) {
2014 		/* Clear iowait_boost if the CPU may have been idle. */
2015 		if (delta_ns > TICK_NSEC)
2016 			cpu->iowait_boost = 0;
2017 		else
2018 			cpu->iowait_boost >>= 1;
2019 	}
2020 	cpu->last_update = time;
2021 	delta_ns = time - cpu->sample.time;
2022 	if ((s64)delta_ns < INTEL_PSTATE_SAMPLING_INTERVAL)
2023 		return;
2024 
2025 	if (intel_pstate_sample(cpu, time))
2026 		intel_pstate_adjust_pstate(cpu);
2027 }
2028 
2029 static struct pstate_funcs core_funcs = {
2030 	.get_max = core_get_max_pstate,
2031 	.get_max_physical = core_get_max_pstate_physical,
2032 	.get_min = core_get_min_pstate,
2033 	.get_turbo = core_get_turbo_pstate,
2034 	.get_scaling = core_get_scaling,
2035 	.get_val = core_get_val,
2036 };
2037 
2038 static const struct pstate_funcs silvermont_funcs = {
2039 	.get_max = atom_get_max_pstate,
2040 	.get_max_physical = atom_get_max_pstate,
2041 	.get_min = atom_get_min_pstate,
2042 	.get_turbo = atom_get_turbo_pstate,
2043 	.get_val = atom_get_val,
2044 	.get_scaling = silvermont_get_scaling,
2045 	.get_vid = atom_get_vid,
2046 };
2047 
2048 static const struct pstate_funcs airmont_funcs = {
2049 	.get_max = atom_get_max_pstate,
2050 	.get_max_physical = atom_get_max_pstate,
2051 	.get_min = atom_get_min_pstate,
2052 	.get_turbo = atom_get_turbo_pstate,
2053 	.get_val = atom_get_val,
2054 	.get_scaling = airmont_get_scaling,
2055 	.get_vid = atom_get_vid,
2056 };
2057 
2058 static const struct pstate_funcs knl_funcs = {
2059 	.get_max = core_get_max_pstate,
2060 	.get_max_physical = core_get_max_pstate_physical,
2061 	.get_min = core_get_min_pstate,
2062 	.get_turbo = knl_get_turbo_pstate,
2063 	.get_aperf_mperf_shift = knl_get_aperf_mperf_shift,
2064 	.get_scaling = core_get_scaling,
2065 	.get_val = core_get_val,
2066 };
2067 
2068 #define X86_MATCH(model, policy)					 \
2069 	X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6, INTEL_FAM6_##model, \
2070 					   X86_FEATURE_APERFMPERF, &policy)
2071 
2072 static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
2073 	X86_MATCH(SANDYBRIDGE,		core_funcs),
2074 	X86_MATCH(SANDYBRIDGE_X,	core_funcs),
2075 	X86_MATCH(ATOM_SILVERMONT,	silvermont_funcs),
2076 	X86_MATCH(IVYBRIDGE,		core_funcs),
2077 	X86_MATCH(HASWELL,		core_funcs),
2078 	X86_MATCH(BROADWELL,		core_funcs),
2079 	X86_MATCH(IVYBRIDGE_X,		core_funcs),
2080 	X86_MATCH(HASWELL_X,		core_funcs),
2081 	X86_MATCH(HASWELL_L,		core_funcs),
2082 	X86_MATCH(HASWELL_G,		core_funcs),
2083 	X86_MATCH(BROADWELL_G,		core_funcs),
2084 	X86_MATCH(ATOM_AIRMONT,		airmont_funcs),
2085 	X86_MATCH(SKYLAKE_L,		core_funcs),
2086 	X86_MATCH(BROADWELL_X,		core_funcs),
2087 	X86_MATCH(SKYLAKE,		core_funcs),
2088 	X86_MATCH(BROADWELL_D,		core_funcs),
2089 	X86_MATCH(XEON_PHI_KNL,		knl_funcs),
2090 	X86_MATCH(XEON_PHI_KNM,		knl_funcs),
2091 	X86_MATCH(ATOM_GOLDMONT,	core_funcs),
2092 	X86_MATCH(ATOM_GOLDMONT_PLUS,	core_funcs),
2093 	X86_MATCH(SKYLAKE_X,		core_funcs),
2094 	{}
2095 };
2096 MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
2097 
2098 static const struct x86_cpu_id intel_pstate_cpu_oob_ids[] __initconst = {
2099 	X86_MATCH(BROADWELL_D,		core_funcs),
2100 	X86_MATCH(BROADWELL_X,		core_funcs),
2101 	X86_MATCH(SKYLAKE_X,		core_funcs),
2102 	{}
2103 };
2104 
2105 static const struct x86_cpu_id intel_pstate_cpu_ee_disable_ids[] = {
2106 	X86_MATCH(KABYLAKE,		core_funcs),
2107 	{}
2108 };
2109 
2110 static const struct x86_cpu_id intel_pstate_hwp_boost_ids[] = {
2111 	X86_MATCH(SKYLAKE_X,		core_funcs),
2112 	X86_MATCH(SKYLAKE,		core_funcs),
2113 	{}
2114 };
2115 
2116 static int intel_pstate_init_cpu(unsigned int cpunum)
2117 {
2118 	struct cpudata *cpu;
2119 
2120 	cpu = all_cpu_data[cpunum];
2121 
2122 	if (!cpu) {
2123 		cpu = kzalloc(sizeof(*cpu), GFP_KERNEL);
2124 		if (!cpu)
2125 			return -ENOMEM;
2126 
2127 		all_cpu_data[cpunum] = cpu;
2128 
2129 		cpu->cpu = cpunum;
2130 
2131 		cpu->epp_default = -EINVAL;
2132 
2133 		if (hwp_active) {
2134 			const struct x86_cpu_id *id;
2135 
2136 			intel_pstate_hwp_enable(cpu);
2137 
2138 			id = x86_match_cpu(intel_pstate_hwp_boost_ids);
2139 			if (id && intel_pstate_acpi_pm_profile_server())
2140 				hwp_boost = true;
2141 		}
2142 	} else if (hwp_active) {
2143 		/*
2144 		 * Re-enable HWP in case this happens after a resume from ACPI
2145 		 * S3 if the CPU was offline during the whole system/resume
2146 		 * cycle.
2147 		 */
2148 		intel_pstate_hwp_reenable(cpu);
2149 	}
2150 
2151 	cpu->epp_powersave = -EINVAL;
2152 	cpu->epp_policy = 0;
2153 
2154 	intel_pstate_get_cpu_pstates(cpu);
2155 
2156 	pr_debug("controlling: cpu %d\n", cpunum);
2157 
2158 	return 0;
2159 }
2160 
2161 static void intel_pstate_set_update_util_hook(unsigned int cpu_num)
2162 {
2163 	struct cpudata *cpu = all_cpu_data[cpu_num];
2164 
2165 	if (hwp_active && !hwp_boost)
2166 		return;
2167 
2168 	if (cpu->update_util_set)
2169 		return;
2170 
2171 	/* Prevent intel_pstate_update_util() from using stale data. */
2172 	cpu->sample.time = 0;
2173 	cpufreq_add_update_util_hook(cpu_num, &cpu->update_util,
2174 				     (hwp_active ?
2175 				      intel_pstate_update_util_hwp :
2176 				      intel_pstate_update_util));
2177 	cpu->update_util_set = true;
2178 }
2179 
2180 static void intel_pstate_clear_update_util_hook(unsigned int cpu)
2181 {
2182 	struct cpudata *cpu_data = all_cpu_data[cpu];
2183 
2184 	if (!cpu_data->update_util_set)
2185 		return;
2186 
2187 	cpufreq_remove_update_util_hook(cpu);
2188 	cpu_data->update_util_set = false;
2189 	synchronize_rcu();
2190 }
2191 
2192 static int intel_pstate_get_max_freq(struct cpudata *cpu)
2193 {
2194 	return global.turbo_disabled || global.no_turbo ?
2195 			cpu->pstate.max_freq : cpu->pstate.turbo_freq;
2196 }
2197 
2198 static void intel_pstate_update_perf_limits(struct cpudata *cpu,
2199 					    unsigned int policy_min,
2200 					    unsigned int policy_max)
2201 {
2202 	int32_t max_policy_perf, min_policy_perf;
2203 	int max_state, turbo_max;
2204 	int max_freq;
2205 
2206 	/*
2207 	 * HWP needs some special consideration, because on BDX the
2208 	 * HWP_REQUEST uses abstract value to represent performance
2209 	 * rather than pure ratios.
2210 	 */
2211 	if (hwp_active) {
2212 		intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state);
2213 	} else {
2214 		max_state = global.no_turbo || global.turbo_disabled ?
2215 			cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
2216 		turbo_max = cpu->pstate.turbo_pstate;
2217 	}
2218 	max_freq = max_state * cpu->pstate.scaling;
2219 
2220 	max_policy_perf = max_state * policy_max / max_freq;
2221 	if (policy_max == policy_min) {
2222 		min_policy_perf = max_policy_perf;
2223 	} else {
2224 		min_policy_perf = max_state * policy_min / max_freq;
2225 		min_policy_perf = clamp_t(int32_t, min_policy_perf,
2226 					  0, max_policy_perf);
2227 	}
2228 
2229 	pr_debug("cpu:%d max_state %d min_policy_perf:%d max_policy_perf:%d\n",
2230 		 cpu->cpu, max_state, min_policy_perf, max_policy_perf);
2231 
2232 	/* Normalize user input to [min_perf, max_perf] */
2233 	if (per_cpu_limits) {
2234 		cpu->min_perf_ratio = min_policy_perf;
2235 		cpu->max_perf_ratio = max_policy_perf;
2236 	} else {
2237 		int32_t global_min, global_max;
2238 
2239 		/* Global limits are in percent of the maximum turbo P-state. */
2240 		global_max = DIV_ROUND_UP(turbo_max * global.max_perf_pct, 100);
2241 		global_min = DIV_ROUND_UP(turbo_max * global.min_perf_pct, 100);
2242 		global_min = clamp_t(int32_t, global_min, 0, global_max);
2243 
2244 		pr_debug("cpu:%d global_min:%d global_max:%d\n", cpu->cpu,
2245 			 global_min, global_max);
2246 
2247 		cpu->min_perf_ratio = max(min_policy_perf, global_min);
2248 		cpu->min_perf_ratio = min(cpu->min_perf_ratio, max_policy_perf);
2249 		cpu->max_perf_ratio = min(max_policy_perf, global_max);
2250 		cpu->max_perf_ratio = max(min_policy_perf, cpu->max_perf_ratio);
2251 
2252 		/* Make sure min_perf <= max_perf */
2253 		cpu->min_perf_ratio = min(cpu->min_perf_ratio,
2254 					  cpu->max_perf_ratio);
2255 
2256 	}
2257 	pr_debug("cpu:%d max_perf_ratio:%d min_perf_ratio:%d\n", cpu->cpu,
2258 		 cpu->max_perf_ratio,
2259 		 cpu->min_perf_ratio);
2260 }
2261 
2262 static int intel_pstate_set_policy(struct cpufreq_policy *policy)
2263 {
2264 	struct cpudata *cpu;
2265 
2266 	if (!policy->cpuinfo.max_freq)
2267 		return -ENODEV;
2268 
2269 	pr_debug("set_policy cpuinfo.max %u policy->max %u\n",
2270 		 policy->cpuinfo.max_freq, policy->max);
2271 
2272 	cpu = all_cpu_data[policy->cpu];
2273 	cpu->policy = policy->policy;
2274 
2275 	mutex_lock(&intel_pstate_limits_lock);
2276 
2277 	intel_pstate_update_perf_limits(cpu, policy->min, policy->max);
2278 
2279 	if (cpu->policy == CPUFREQ_POLICY_PERFORMANCE) {
2280 		/*
2281 		 * NOHZ_FULL CPUs need this as the governor callback may not
2282 		 * be invoked on them.
2283 		 */
2284 		intel_pstate_clear_update_util_hook(policy->cpu);
2285 		intel_pstate_max_within_limits(cpu);
2286 	} else {
2287 		intel_pstate_set_update_util_hook(policy->cpu);
2288 	}
2289 
2290 	if (hwp_active) {
2291 		/*
2292 		 * When hwp_boost was active before and dynamically it
2293 		 * was turned off, in that case we need to clear the
2294 		 * update util hook.
2295 		 */
2296 		if (!hwp_boost)
2297 			intel_pstate_clear_update_util_hook(policy->cpu);
2298 		intel_pstate_hwp_set(policy->cpu);
2299 	}
2300 
2301 	mutex_unlock(&intel_pstate_limits_lock);
2302 
2303 	return 0;
2304 }
2305 
2306 static void intel_pstate_adjust_policy_max(struct cpudata *cpu,
2307 					   struct cpufreq_policy_data *policy)
2308 {
2309 	if (!hwp_active &&
2310 	    cpu->pstate.max_pstate_physical > cpu->pstate.max_pstate &&
2311 	    policy->max < policy->cpuinfo.max_freq &&
2312 	    policy->max > cpu->pstate.max_freq) {
2313 		pr_debug("policy->max > max non turbo frequency\n");
2314 		policy->max = policy->cpuinfo.max_freq;
2315 	}
2316 }
2317 
2318 static void intel_pstate_verify_cpu_policy(struct cpudata *cpu,
2319 					   struct cpufreq_policy_data *policy)
2320 {
2321 	int max_freq;
2322 
2323 	update_turbo_state();
2324 	if (hwp_active) {
2325 		int max_state, turbo_max;
2326 
2327 		intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state);
2328 		max_freq = max_state * cpu->pstate.scaling;
2329 	} else {
2330 		max_freq = intel_pstate_get_max_freq(cpu);
2331 	}
2332 	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, max_freq);
2333 
2334 	intel_pstate_adjust_policy_max(cpu, policy);
2335 }
2336 
2337 static int intel_pstate_verify_policy(struct cpufreq_policy_data *policy)
2338 {
2339 	intel_pstate_verify_cpu_policy(all_cpu_data[policy->cpu], policy);
2340 
2341 	return 0;
2342 }
2343 
2344 static int intel_pstate_cpu_offline(struct cpufreq_policy *policy)
2345 {
2346 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2347 
2348 	pr_debug("CPU %d going offline\n", cpu->cpu);
2349 
2350 	if (cpu->suspended)
2351 		return 0;
2352 
2353 	/*
2354 	 * If the CPU is an SMT thread and it goes offline with the performance
2355 	 * settings different from the minimum, it will prevent its sibling
2356 	 * from getting to lower performance levels, so force the minimum
2357 	 * performance on CPU offline to prevent that from happening.
2358 	 */
2359 	if (hwp_active)
2360 		intel_pstate_hwp_offline(cpu);
2361 	else
2362 		intel_pstate_set_min_pstate(cpu);
2363 
2364 	intel_pstate_exit_perf_limits(policy);
2365 
2366 	return 0;
2367 }
2368 
2369 static int intel_pstate_cpu_online(struct cpufreq_policy *policy)
2370 {
2371 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2372 
2373 	pr_debug("CPU %d going online\n", cpu->cpu);
2374 
2375 	intel_pstate_init_acpi_perf_limits(policy);
2376 
2377 	if (hwp_active) {
2378 		/*
2379 		 * Re-enable HWP and clear the "suspended" flag to let "resume"
2380 		 * know that it need not do that.
2381 		 */
2382 		intel_pstate_hwp_reenable(cpu);
2383 		cpu->suspended = false;
2384 	}
2385 
2386 	return 0;
2387 }
2388 
2389 static void intel_pstate_stop_cpu(struct cpufreq_policy *policy)
2390 {
2391 	pr_debug("CPU %d stopping\n", policy->cpu);
2392 
2393 	intel_pstate_clear_update_util_hook(policy->cpu);
2394 }
2395 
2396 static int intel_pstate_cpu_exit(struct cpufreq_policy *policy)
2397 {
2398 	pr_debug("CPU %d exiting\n", policy->cpu);
2399 
2400 	policy->fast_switch_possible = false;
2401 
2402 	return 0;
2403 }
2404 
2405 static int __intel_pstate_cpu_init(struct cpufreq_policy *policy)
2406 {
2407 	struct cpudata *cpu;
2408 	int rc;
2409 
2410 	rc = intel_pstate_init_cpu(policy->cpu);
2411 	if (rc)
2412 		return rc;
2413 
2414 	cpu = all_cpu_data[policy->cpu];
2415 
2416 	cpu->max_perf_ratio = 0xFF;
2417 	cpu->min_perf_ratio = 0;
2418 
2419 	policy->min = cpu->pstate.min_pstate * cpu->pstate.scaling;
2420 	policy->max = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
2421 
2422 	/* cpuinfo and default policy values */
2423 	policy->cpuinfo.min_freq = cpu->pstate.min_pstate * cpu->pstate.scaling;
2424 	update_turbo_state();
2425 	global.turbo_disabled_mf = global.turbo_disabled;
2426 	policy->cpuinfo.max_freq = global.turbo_disabled ?
2427 			cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
2428 	policy->cpuinfo.max_freq *= cpu->pstate.scaling;
2429 
2430 	if (hwp_active) {
2431 		unsigned int max_freq;
2432 
2433 		max_freq = global.turbo_disabled ?
2434 			cpu->pstate.max_freq : cpu->pstate.turbo_freq;
2435 		if (max_freq < policy->cpuinfo.max_freq)
2436 			policy->cpuinfo.max_freq = max_freq;
2437 	}
2438 
2439 	intel_pstate_init_acpi_perf_limits(policy);
2440 
2441 	policy->fast_switch_possible = true;
2442 
2443 	return 0;
2444 }
2445 
2446 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
2447 {
2448 	int ret = __intel_pstate_cpu_init(policy);
2449 
2450 	if (ret)
2451 		return ret;
2452 
2453 	/*
2454 	 * Set the policy to powersave to provide a valid fallback value in case
2455 	 * the default cpufreq governor is neither powersave nor performance.
2456 	 */
2457 	policy->policy = CPUFREQ_POLICY_POWERSAVE;
2458 
2459 	if (hwp_active) {
2460 		struct cpudata *cpu = all_cpu_data[policy->cpu];
2461 
2462 		cpu->epp_cached = intel_pstate_get_epp(cpu, 0);
2463 	}
2464 
2465 	return 0;
2466 }
2467 
2468 static struct cpufreq_driver intel_pstate = {
2469 	.flags		= CPUFREQ_CONST_LOOPS,
2470 	.verify		= intel_pstate_verify_policy,
2471 	.setpolicy	= intel_pstate_set_policy,
2472 	.suspend	= intel_pstate_suspend,
2473 	.resume		= intel_pstate_resume,
2474 	.init		= intel_pstate_cpu_init,
2475 	.exit		= intel_pstate_cpu_exit,
2476 	.stop_cpu	= intel_pstate_stop_cpu,
2477 	.offline	= intel_pstate_cpu_offline,
2478 	.online		= intel_pstate_cpu_online,
2479 	.update_limits	= intel_pstate_update_limits,
2480 	.name		= "intel_pstate",
2481 };
2482 
2483 static int intel_cpufreq_verify_policy(struct cpufreq_policy_data *policy)
2484 {
2485 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2486 
2487 	intel_pstate_verify_cpu_policy(cpu, policy);
2488 	intel_pstate_update_perf_limits(cpu, policy->min, policy->max);
2489 
2490 	return 0;
2491 }
2492 
2493 /* Use of trace in passive mode:
2494  *
2495  * In passive mode the trace core_busy field (also known as the
2496  * performance field, and lablelled as such on the graphs; also known as
2497  * core_avg_perf) is not needed and so is re-assigned to indicate if the
2498  * driver call was via the normal or fast switch path. Various graphs
2499  * output from the intel_pstate_tracer.py utility that include core_busy
2500  * (or performance or core_avg_perf) have a fixed y-axis from 0 to 100%,
2501  * so we use 10 to indicate the normal path through the driver, and
2502  * 90 to indicate the fast switch path through the driver.
2503  * The scaled_busy field is not used, and is set to 0.
2504  */
2505 
2506 #define	INTEL_PSTATE_TRACE_TARGET 10
2507 #define	INTEL_PSTATE_TRACE_FAST_SWITCH 90
2508 
2509 static void intel_cpufreq_trace(struct cpudata *cpu, unsigned int trace_type, int old_pstate)
2510 {
2511 	struct sample *sample;
2512 
2513 	if (!trace_pstate_sample_enabled())
2514 		return;
2515 
2516 	if (!intel_pstate_sample(cpu, ktime_get()))
2517 		return;
2518 
2519 	sample = &cpu->sample;
2520 	trace_pstate_sample(trace_type,
2521 		0,
2522 		old_pstate,
2523 		cpu->pstate.current_pstate,
2524 		sample->mperf,
2525 		sample->aperf,
2526 		sample->tsc,
2527 		get_avg_frequency(cpu),
2528 		fp_toint(cpu->iowait_boost * 100));
2529 }
2530 
2531 static void intel_cpufreq_hwp_update(struct cpudata *cpu, u32 min, u32 max,
2532 				     u32 desired, bool fast_switch)
2533 {
2534 	u64 prev = READ_ONCE(cpu->hwp_req_cached), value = prev;
2535 
2536 	value &= ~HWP_MIN_PERF(~0L);
2537 	value |= HWP_MIN_PERF(min);
2538 
2539 	value &= ~HWP_MAX_PERF(~0L);
2540 	value |= HWP_MAX_PERF(max);
2541 
2542 	value &= ~HWP_DESIRED_PERF(~0L);
2543 	value |= HWP_DESIRED_PERF(desired);
2544 
2545 	if (value == prev)
2546 		return;
2547 
2548 	WRITE_ONCE(cpu->hwp_req_cached, value);
2549 	if (fast_switch)
2550 		wrmsrl(MSR_HWP_REQUEST, value);
2551 	else
2552 		wrmsrl_on_cpu(cpu->cpu, MSR_HWP_REQUEST, value);
2553 }
2554 
2555 static void intel_cpufreq_perf_ctl_update(struct cpudata *cpu,
2556 					  u32 target_pstate, bool fast_switch)
2557 {
2558 	if (fast_switch)
2559 		wrmsrl(MSR_IA32_PERF_CTL,
2560 		       pstate_funcs.get_val(cpu, target_pstate));
2561 	else
2562 		wrmsrl_on_cpu(cpu->cpu, MSR_IA32_PERF_CTL,
2563 			      pstate_funcs.get_val(cpu, target_pstate));
2564 }
2565 
2566 static int intel_cpufreq_update_pstate(struct cpufreq_policy *policy,
2567 				       int target_pstate, bool fast_switch)
2568 {
2569 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2570 	int old_pstate = cpu->pstate.current_pstate;
2571 
2572 	target_pstate = intel_pstate_prepare_request(cpu, target_pstate);
2573 	if (hwp_active) {
2574 		int max_pstate = policy->strict_target ?
2575 					target_pstate : cpu->max_perf_ratio;
2576 
2577 		intel_cpufreq_hwp_update(cpu, target_pstate, max_pstate, 0,
2578 					 fast_switch);
2579 	} else if (target_pstate != old_pstate) {
2580 		intel_cpufreq_perf_ctl_update(cpu, target_pstate, fast_switch);
2581 	}
2582 
2583 	cpu->pstate.current_pstate = target_pstate;
2584 
2585 	intel_cpufreq_trace(cpu, fast_switch ? INTEL_PSTATE_TRACE_FAST_SWITCH :
2586 			    INTEL_PSTATE_TRACE_TARGET, old_pstate);
2587 
2588 	return target_pstate;
2589 }
2590 
2591 static int intel_cpufreq_target(struct cpufreq_policy *policy,
2592 				unsigned int target_freq,
2593 				unsigned int relation)
2594 {
2595 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2596 	struct cpufreq_freqs freqs;
2597 	int target_pstate;
2598 
2599 	update_turbo_state();
2600 
2601 	freqs.old = policy->cur;
2602 	freqs.new = target_freq;
2603 
2604 	cpufreq_freq_transition_begin(policy, &freqs);
2605 
2606 	switch (relation) {
2607 	case CPUFREQ_RELATION_L:
2608 		target_pstate = DIV_ROUND_UP(freqs.new, cpu->pstate.scaling);
2609 		break;
2610 	case CPUFREQ_RELATION_H:
2611 		target_pstate = freqs.new / cpu->pstate.scaling;
2612 		break;
2613 	default:
2614 		target_pstate = DIV_ROUND_CLOSEST(freqs.new, cpu->pstate.scaling);
2615 		break;
2616 	}
2617 
2618 	target_pstate = intel_cpufreq_update_pstate(policy, target_pstate, false);
2619 
2620 	freqs.new = target_pstate * cpu->pstate.scaling;
2621 
2622 	cpufreq_freq_transition_end(policy, &freqs, false);
2623 
2624 	return 0;
2625 }
2626 
2627 static unsigned int intel_cpufreq_fast_switch(struct cpufreq_policy *policy,
2628 					      unsigned int target_freq)
2629 {
2630 	struct cpudata *cpu = all_cpu_data[policy->cpu];
2631 	int target_pstate;
2632 
2633 	update_turbo_state();
2634 
2635 	target_pstate = DIV_ROUND_UP(target_freq, cpu->pstate.scaling);
2636 
2637 	target_pstate = intel_cpufreq_update_pstate(policy, target_pstate, true);
2638 
2639 	return target_pstate * cpu->pstate.scaling;
2640 }
2641 
2642 static void intel_cpufreq_adjust_perf(unsigned int cpunum,
2643 				      unsigned long min_perf,
2644 				      unsigned long target_perf,
2645 				      unsigned long capacity)
2646 {
2647 	struct cpudata *cpu = all_cpu_data[cpunum];
2648 	u64 hwp_cap = READ_ONCE(cpu->hwp_cap_cached);
2649 	int old_pstate = cpu->pstate.current_pstate;
2650 	int cap_pstate, min_pstate, max_pstate, target_pstate;
2651 
2652 	update_turbo_state();
2653 	cap_pstate = global.turbo_disabled ? HWP_GUARANTEED_PERF(hwp_cap) :
2654 					     HWP_HIGHEST_PERF(hwp_cap);
2655 
2656 	/* Optimization: Avoid unnecessary divisions. */
2657 
2658 	target_pstate = cap_pstate;
2659 	if (target_perf < capacity)
2660 		target_pstate = DIV_ROUND_UP(cap_pstate * target_perf, capacity);
2661 
2662 	min_pstate = cap_pstate;
2663 	if (min_perf < capacity)
2664 		min_pstate = DIV_ROUND_UP(cap_pstate * min_perf, capacity);
2665 
2666 	if (min_pstate < cpu->pstate.min_pstate)
2667 		min_pstate = cpu->pstate.min_pstate;
2668 
2669 	if (min_pstate < cpu->min_perf_ratio)
2670 		min_pstate = cpu->min_perf_ratio;
2671 
2672 	max_pstate = min(cap_pstate, cpu->max_perf_ratio);
2673 	if (max_pstate < min_pstate)
2674 		max_pstate = min_pstate;
2675 
2676 	target_pstate = clamp_t(int, target_pstate, min_pstate, max_pstate);
2677 
2678 	intel_cpufreq_hwp_update(cpu, min_pstate, max_pstate, target_pstate, true);
2679 
2680 	cpu->pstate.current_pstate = target_pstate;
2681 	intel_cpufreq_trace(cpu, INTEL_PSTATE_TRACE_FAST_SWITCH, old_pstate);
2682 }
2683 
2684 static int intel_cpufreq_cpu_init(struct cpufreq_policy *policy)
2685 {
2686 	int max_state, turbo_max, min_freq, max_freq, ret;
2687 	struct freq_qos_request *req;
2688 	struct cpudata *cpu;
2689 	struct device *dev;
2690 
2691 	dev = get_cpu_device(policy->cpu);
2692 	if (!dev)
2693 		return -ENODEV;
2694 
2695 	ret = __intel_pstate_cpu_init(policy);
2696 	if (ret)
2697 		return ret;
2698 
2699 	policy->cpuinfo.transition_latency = INTEL_CPUFREQ_TRANSITION_LATENCY;
2700 	/* This reflects the intel_pstate_get_cpu_pstates() setting. */
2701 	policy->cur = policy->cpuinfo.min_freq;
2702 
2703 	req = kcalloc(2, sizeof(*req), GFP_KERNEL);
2704 	if (!req) {
2705 		ret = -ENOMEM;
2706 		goto pstate_exit;
2707 	}
2708 
2709 	cpu = all_cpu_data[policy->cpu];
2710 
2711 	if (hwp_active) {
2712 		u64 value;
2713 
2714 		intel_pstate_get_hwp_max(cpu, &turbo_max, &max_state);
2715 		policy->transition_delay_us = INTEL_CPUFREQ_TRANSITION_DELAY_HWP;
2716 		rdmsrl_on_cpu(cpu->cpu, MSR_HWP_REQUEST, &value);
2717 		WRITE_ONCE(cpu->hwp_req_cached, value);
2718 		cpu->epp_cached = intel_pstate_get_epp(cpu, value);
2719 	} else {
2720 		turbo_max = cpu->pstate.turbo_pstate;
2721 		policy->transition_delay_us = INTEL_CPUFREQ_TRANSITION_DELAY;
2722 	}
2723 
2724 	min_freq = DIV_ROUND_UP(turbo_max * global.min_perf_pct, 100);
2725 	min_freq *= cpu->pstate.scaling;
2726 	max_freq = DIV_ROUND_UP(turbo_max * global.max_perf_pct, 100);
2727 	max_freq *= cpu->pstate.scaling;
2728 
2729 	ret = freq_qos_add_request(&policy->constraints, req, FREQ_QOS_MIN,
2730 				   min_freq);
2731 	if (ret < 0) {
2732 		dev_err(dev, "Failed to add min-freq constraint (%d)\n", ret);
2733 		goto free_req;
2734 	}
2735 
2736 	ret = freq_qos_add_request(&policy->constraints, req + 1, FREQ_QOS_MAX,
2737 				   max_freq);
2738 	if (ret < 0) {
2739 		dev_err(dev, "Failed to add max-freq constraint (%d)\n", ret);
2740 		goto remove_min_req;
2741 	}
2742 
2743 	policy->driver_data = req;
2744 
2745 	return 0;
2746 
2747 remove_min_req:
2748 	freq_qos_remove_request(req);
2749 free_req:
2750 	kfree(req);
2751 pstate_exit:
2752 	intel_pstate_exit_perf_limits(policy);
2753 
2754 	return ret;
2755 }
2756 
2757 static int intel_cpufreq_cpu_exit(struct cpufreq_policy *policy)
2758 {
2759 	struct freq_qos_request *req;
2760 
2761 	req = policy->driver_data;
2762 
2763 	freq_qos_remove_request(req + 1);
2764 	freq_qos_remove_request(req);
2765 	kfree(req);
2766 
2767 	return intel_pstate_cpu_exit(policy);
2768 }
2769 
2770 static struct cpufreq_driver intel_cpufreq = {
2771 	.flags		= CPUFREQ_CONST_LOOPS,
2772 	.verify		= intel_cpufreq_verify_policy,
2773 	.target		= intel_cpufreq_target,
2774 	.fast_switch	= intel_cpufreq_fast_switch,
2775 	.init		= intel_cpufreq_cpu_init,
2776 	.exit		= intel_cpufreq_cpu_exit,
2777 	.offline	= intel_pstate_cpu_offline,
2778 	.online		= intel_pstate_cpu_online,
2779 	.suspend	= intel_pstate_suspend,
2780 	.resume		= intel_pstate_resume,
2781 	.update_limits	= intel_pstate_update_limits,
2782 	.name		= "intel_cpufreq",
2783 };
2784 
2785 static struct cpufreq_driver *default_driver;
2786 
2787 static void intel_pstate_driver_cleanup(void)
2788 {
2789 	unsigned int cpu;
2790 
2791 	get_online_cpus();
2792 	for_each_online_cpu(cpu) {
2793 		if (all_cpu_data[cpu]) {
2794 			if (intel_pstate_driver == &intel_pstate)
2795 				intel_pstate_clear_update_util_hook(cpu);
2796 
2797 			kfree(all_cpu_data[cpu]);
2798 			all_cpu_data[cpu] = NULL;
2799 		}
2800 	}
2801 	put_online_cpus();
2802 
2803 	intel_pstate_driver = NULL;
2804 }
2805 
2806 static int intel_pstate_register_driver(struct cpufreq_driver *driver)
2807 {
2808 	int ret;
2809 
2810 	if (driver == &intel_pstate)
2811 		intel_pstate_sysfs_expose_hwp_dynamic_boost();
2812 
2813 	memset(&global, 0, sizeof(global));
2814 	global.max_perf_pct = 100;
2815 
2816 	intel_pstate_driver = driver;
2817 	ret = cpufreq_register_driver(intel_pstate_driver);
2818 	if (ret) {
2819 		intel_pstate_driver_cleanup();
2820 		return ret;
2821 	}
2822 
2823 	global.min_perf_pct = min_perf_pct_min();
2824 
2825 	return 0;
2826 }
2827 
2828 static ssize_t intel_pstate_show_status(char *buf)
2829 {
2830 	if (!intel_pstate_driver)
2831 		return sprintf(buf, "off\n");
2832 
2833 	return sprintf(buf, "%s\n", intel_pstate_driver == &intel_pstate ?
2834 					"active" : "passive");
2835 }
2836 
2837 static int intel_pstate_update_status(const char *buf, size_t size)
2838 {
2839 	if (size == 3 && !strncmp(buf, "off", size)) {
2840 		if (!intel_pstate_driver)
2841 			return -EINVAL;
2842 
2843 		if (hwp_active)
2844 			return -EBUSY;
2845 
2846 		cpufreq_unregister_driver(intel_pstate_driver);
2847 		intel_pstate_driver_cleanup();
2848 		return 0;
2849 	}
2850 
2851 	if (size == 6 && !strncmp(buf, "active", size)) {
2852 		if (intel_pstate_driver) {
2853 			if (intel_pstate_driver == &intel_pstate)
2854 				return 0;
2855 
2856 			cpufreq_unregister_driver(intel_pstate_driver);
2857 		}
2858 
2859 		return intel_pstate_register_driver(&intel_pstate);
2860 	}
2861 
2862 	if (size == 7 && !strncmp(buf, "passive", size)) {
2863 		if (intel_pstate_driver) {
2864 			if (intel_pstate_driver == &intel_cpufreq)
2865 				return 0;
2866 
2867 			cpufreq_unregister_driver(intel_pstate_driver);
2868 			intel_pstate_sysfs_hide_hwp_dynamic_boost();
2869 		}
2870 
2871 		return intel_pstate_register_driver(&intel_cpufreq);
2872 	}
2873 
2874 	return -EINVAL;
2875 }
2876 
2877 static int no_load __initdata;
2878 static int no_hwp __initdata;
2879 static int hwp_only __initdata;
2880 static unsigned int force_load __initdata;
2881 
2882 static int __init intel_pstate_msrs_not_valid(void)
2883 {
2884 	if (!pstate_funcs.get_max() ||
2885 	    !pstate_funcs.get_min() ||
2886 	    !pstate_funcs.get_turbo())
2887 		return -ENODEV;
2888 
2889 	return 0;
2890 }
2891 
2892 static void __init copy_cpu_funcs(struct pstate_funcs *funcs)
2893 {
2894 	pstate_funcs.get_max   = funcs->get_max;
2895 	pstate_funcs.get_max_physical = funcs->get_max_physical;
2896 	pstate_funcs.get_min   = funcs->get_min;
2897 	pstate_funcs.get_turbo = funcs->get_turbo;
2898 	pstate_funcs.get_scaling = funcs->get_scaling;
2899 	pstate_funcs.get_val   = funcs->get_val;
2900 	pstate_funcs.get_vid   = funcs->get_vid;
2901 	pstate_funcs.get_aperf_mperf_shift = funcs->get_aperf_mperf_shift;
2902 }
2903 
2904 #ifdef CONFIG_ACPI
2905 
2906 static bool __init intel_pstate_no_acpi_pss(void)
2907 {
2908 	int i;
2909 
2910 	for_each_possible_cpu(i) {
2911 		acpi_status status;
2912 		union acpi_object *pss;
2913 		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
2914 		struct acpi_processor *pr = per_cpu(processors, i);
2915 
2916 		if (!pr)
2917 			continue;
2918 
2919 		status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
2920 		if (ACPI_FAILURE(status))
2921 			continue;
2922 
2923 		pss = buffer.pointer;
2924 		if (pss && pss->type == ACPI_TYPE_PACKAGE) {
2925 			kfree(pss);
2926 			return false;
2927 		}
2928 
2929 		kfree(pss);
2930 	}
2931 
2932 	pr_debug("ACPI _PSS not found\n");
2933 	return true;
2934 }
2935 
2936 static bool __init intel_pstate_no_acpi_pcch(void)
2937 {
2938 	acpi_status status;
2939 	acpi_handle handle;
2940 
2941 	status = acpi_get_handle(NULL, "\\_SB", &handle);
2942 	if (ACPI_FAILURE(status))
2943 		goto not_found;
2944 
2945 	if (acpi_has_method(handle, "PCCH"))
2946 		return false;
2947 
2948 not_found:
2949 	pr_debug("ACPI PCCH not found\n");
2950 	return true;
2951 }
2952 
2953 static bool __init intel_pstate_has_acpi_ppc(void)
2954 {
2955 	int i;
2956 
2957 	for_each_possible_cpu(i) {
2958 		struct acpi_processor *pr = per_cpu(processors, i);
2959 
2960 		if (!pr)
2961 			continue;
2962 		if (acpi_has_method(pr->handle, "_PPC"))
2963 			return true;
2964 	}
2965 	pr_debug("ACPI _PPC not found\n");
2966 	return false;
2967 }
2968 
2969 enum {
2970 	PSS,
2971 	PPC,
2972 };
2973 
2974 /* Hardware vendor-specific info that has its own power management modes */
2975 static struct acpi_platform_list plat_info[] __initdata = {
2976 	{"HP    ", "ProLiant", 0, ACPI_SIG_FADT, all_versions, NULL, PSS},
2977 	{"ORACLE", "X4-2    ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2978 	{"ORACLE", "X4-2L   ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2979 	{"ORACLE", "X4-2B   ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2980 	{"ORACLE", "X3-2    ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2981 	{"ORACLE", "X3-2L   ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2982 	{"ORACLE", "X3-2B   ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2983 	{"ORACLE", "X4470M2 ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2984 	{"ORACLE", "X4270M3 ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2985 	{"ORACLE", "X4270M2 ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2986 	{"ORACLE", "X4170M2 ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2987 	{"ORACLE", "X4170 M3", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2988 	{"ORACLE", "X4275 M3", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2989 	{"ORACLE", "X6-2    ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2990 	{"ORACLE", "Sudbury ", 0, ACPI_SIG_FADT, all_versions, NULL, PPC},
2991 	{ } /* End */
2992 };
2993 
2994 #define BITMASK_OOB	(BIT(8) | BIT(18))
2995 
2996 static bool __init intel_pstate_platform_pwr_mgmt_exists(void)
2997 {
2998 	const struct x86_cpu_id *id;
2999 	u64 misc_pwr;
3000 	int idx;
3001 
3002 	id = x86_match_cpu(intel_pstate_cpu_oob_ids);
3003 	if (id) {
3004 		rdmsrl(MSR_MISC_PWR_MGMT, misc_pwr);
3005 		if (misc_pwr & BITMASK_OOB) {
3006 			pr_debug("Bit 8 or 18 in the MISC_PWR_MGMT MSR set\n");
3007 			pr_debug("P states are controlled in Out of Band mode by the firmware/hardware\n");
3008 			return true;
3009 		}
3010 	}
3011 
3012 	idx = acpi_match_platform_list(plat_info);
3013 	if (idx < 0)
3014 		return false;
3015 
3016 	switch (plat_info[idx].data) {
3017 	case PSS:
3018 		if (!intel_pstate_no_acpi_pss())
3019 			return false;
3020 
3021 		return intel_pstate_no_acpi_pcch();
3022 	case PPC:
3023 		return intel_pstate_has_acpi_ppc() && !force_load;
3024 	}
3025 
3026 	return false;
3027 }
3028 
3029 static void intel_pstate_request_control_from_smm(void)
3030 {
3031 	/*
3032 	 * It may be unsafe to request P-states control from SMM if _PPC support
3033 	 * has not been enabled.
3034 	 */
3035 	if (acpi_ppc)
3036 		acpi_processor_pstate_control();
3037 }
3038 #else /* CONFIG_ACPI not enabled */
3039 static inline bool intel_pstate_platform_pwr_mgmt_exists(void) { return false; }
3040 static inline bool intel_pstate_has_acpi_ppc(void) { return false; }
3041 static inline void intel_pstate_request_control_from_smm(void) {}
3042 #endif /* CONFIG_ACPI */
3043 
3044 #define INTEL_PSTATE_HWP_BROADWELL	0x01
3045 
3046 #define X86_MATCH_HWP(model, hwp_mode)					\
3047 	X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6, INTEL_FAM6_##model, \
3048 					   X86_FEATURE_HWP, hwp_mode)
3049 
3050 static const struct x86_cpu_id hwp_support_ids[] __initconst = {
3051 	X86_MATCH_HWP(BROADWELL_X,	INTEL_PSTATE_HWP_BROADWELL),
3052 	X86_MATCH_HWP(BROADWELL_D,	INTEL_PSTATE_HWP_BROADWELL),
3053 	X86_MATCH_HWP(ANY,		0),
3054 	{}
3055 };
3056 
3057 static int __init intel_pstate_init(void)
3058 {
3059 	const struct x86_cpu_id *id;
3060 	int rc;
3061 
3062 	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
3063 		return -ENODEV;
3064 
3065 	if (no_load)
3066 		return -ENODEV;
3067 
3068 	id = x86_match_cpu(hwp_support_ids);
3069 	if (id) {
3070 		copy_cpu_funcs(&core_funcs);
3071 		/*
3072 		 * Avoid enabling HWP for processors without EPP support,
3073 		 * because that means incomplete HWP implementation which is a
3074 		 * corner case and supporting it is generally problematic.
3075 		 */
3076 		if (!no_hwp && boot_cpu_has(X86_FEATURE_HWP_EPP)) {
3077 			hwp_active++;
3078 			hwp_mode_bdw = id->driver_data;
3079 			intel_pstate.attr = hwp_cpufreq_attrs;
3080 			intel_cpufreq.attr = hwp_cpufreq_attrs;
3081 			intel_cpufreq.flags |= CPUFREQ_NEED_UPDATE_LIMITS;
3082 			intel_cpufreq.adjust_perf = intel_cpufreq_adjust_perf;
3083 			if (!default_driver)
3084 				default_driver = &intel_pstate;
3085 
3086 			goto hwp_cpu_matched;
3087 		}
3088 	} else {
3089 		id = x86_match_cpu(intel_pstate_cpu_ids);
3090 		if (!id) {
3091 			pr_info("CPU model not supported\n");
3092 			return -ENODEV;
3093 		}
3094 
3095 		copy_cpu_funcs((struct pstate_funcs *)id->driver_data);
3096 	}
3097 
3098 	if (intel_pstate_msrs_not_valid()) {
3099 		pr_info("Invalid MSRs\n");
3100 		return -ENODEV;
3101 	}
3102 	/* Without HWP start in the passive mode. */
3103 	if (!default_driver)
3104 		default_driver = &intel_cpufreq;
3105 
3106 hwp_cpu_matched:
3107 	/*
3108 	 * The Intel pstate driver will be ignored if the platform
3109 	 * firmware has its own power management modes.
3110 	 */
3111 	if (intel_pstate_platform_pwr_mgmt_exists()) {
3112 		pr_info("P-states controlled by the platform\n");
3113 		return -ENODEV;
3114 	}
3115 
3116 	if (!hwp_active && hwp_only)
3117 		return -ENOTSUPP;
3118 
3119 	pr_info("Intel P-state driver initializing\n");
3120 
3121 	all_cpu_data = vzalloc(array_size(sizeof(void *), num_possible_cpus()));
3122 	if (!all_cpu_data)
3123 		return -ENOMEM;
3124 
3125 	intel_pstate_request_control_from_smm();
3126 
3127 	intel_pstate_sysfs_expose_params();
3128 
3129 	mutex_lock(&intel_pstate_driver_lock);
3130 	rc = intel_pstate_register_driver(default_driver);
3131 	mutex_unlock(&intel_pstate_driver_lock);
3132 	if (rc) {
3133 		intel_pstate_sysfs_remove();
3134 		return rc;
3135 	}
3136 
3137 	if (hwp_active) {
3138 		const struct x86_cpu_id *id;
3139 
3140 		id = x86_match_cpu(intel_pstate_cpu_ee_disable_ids);
3141 		if (id) {
3142 			set_power_ctl_ee_state(false);
3143 			pr_info("Disabling energy efficiency optimization\n");
3144 		}
3145 
3146 		pr_info("HWP enabled\n");
3147 	}
3148 
3149 	return 0;
3150 }
3151 device_initcall(intel_pstate_init);
3152 
3153 static int __init intel_pstate_setup(char *str)
3154 {
3155 	if (!str)
3156 		return -EINVAL;
3157 
3158 	if (!strcmp(str, "disable"))
3159 		no_load = 1;
3160 	else if (!strcmp(str, "active"))
3161 		default_driver = &intel_pstate;
3162 	else if (!strcmp(str, "passive"))
3163 		default_driver = &intel_cpufreq;
3164 
3165 	if (!strcmp(str, "no_hwp")) {
3166 		pr_info("HWP disabled\n");
3167 		no_hwp = 1;
3168 	}
3169 	if (!strcmp(str, "force"))
3170 		force_load = 1;
3171 	if (!strcmp(str, "hwp_only"))
3172 		hwp_only = 1;
3173 	if (!strcmp(str, "per_cpu_perf_limits"))
3174 		per_cpu_limits = true;
3175 
3176 #ifdef CONFIG_ACPI
3177 	if (!strcmp(str, "support_acpi_ppc"))
3178 		acpi_ppc = true;
3179 #endif
3180 
3181 	return 0;
3182 }
3183 early_param("intel_pstate", intel_pstate_setup);
3184 
3185 MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>");
3186 MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors");
3187 MODULE_LICENSE("GPL");
3188