1 /*
2  * intel_pstate.c: Native P state management for Intel processors
3  *
4  * (C) Copyright 2012 Intel Corporation
5  * Author: Dirk Brandewie <dirk.j.brandewie@intel.com>
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License
9  * as published by the Free Software Foundation; version 2
10  * of the License.
11  */
12 
13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 
15 #include <linux/kernel.h>
16 #include <linux/kernel_stat.h>
17 #include <linux/module.h>
18 #include <linux/ktime.h>
19 #include <linux/hrtimer.h>
20 #include <linux/tick.h>
21 #include <linux/slab.h>
22 #include <linux/sched.h>
23 #include <linux/list.h>
24 #include <linux/cpu.h>
25 #include <linux/cpufreq.h>
26 #include <linux/sysfs.h>
27 #include <linux/types.h>
28 #include <linux/fs.h>
29 #include <linux/debugfs.h>
30 #include <linux/acpi.h>
31 #include <linux/vmalloc.h>
32 #include <trace/events/power.h>
33 
34 #include <asm/div64.h>
35 #include <asm/msr.h>
36 #include <asm/cpu_device_id.h>
37 #include <asm/cpufeature.h>
38 #include <asm/intel-family.h>
39 
40 #define ATOM_RATIOS		0x66a
41 #define ATOM_VIDS		0x66b
42 #define ATOM_TURBO_RATIOS	0x66c
43 #define ATOM_TURBO_VIDS		0x66d
44 
45 #ifdef CONFIG_ACPI
46 #include <acpi/processor.h>
47 #endif
48 
49 #define FRAC_BITS 8
50 #define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
51 #define fp_toint(X) ((X) >> FRAC_BITS)
52 
53 #define EXT_BITS 6
54 #define EXT_FRAC_BITS (EXT_BITS + FRAC_BITS)
55 
56 static inline int32_t mul_fp(int32_t x, int32_t y)
57 {
58 	return ((int64_t)x * (int64_t)y) >> FRAC_BITS;
59 }
60 
61 static inline int32_t div_fp(s64 x, s64 y)
62 {
63 	return div64_s64((int64_t)x << FRAC_BITS, y);
64 }
65 
66 static inline int ceiling_fp(int32_t x)
67 {
68 	int mask, ret;
69 
70 	ret = fp_toint(x);
71 	mask = (1 << FRAC_BITS) - 1;
72 	if (x & mask)
73 		ret += 1;
74 	return ret;
75 }
76 
77 static inline u64 mul_ext_fp(u64 x, u64 y)
78 {
79 	return (x * y) >> EXT_FRAC_BITS;
80 }
81 
82 static inline u64 div_ext_fp(u64 x, u64 y)
83 {
84 	return div64_u64(x << EXT_FRAC_BITS, y);
85 }
86 
87 /**
88  * struct sample -	Store performance sample
89  * @core_avg_perf:	Ratio of APERF/MPERF which is the actual average
90  *			performance during last sample period
91  * @busy_scaled:	Scaled busy value which is used to calculate next
92  *			P state. This can be different than core_avg_perf
93  *			to account for cpu idle period
94  * @aperf:		Difference of actual performance frequency clock count
95  *			read from APERF MSR between last and current sample
96  * @mperf:		Difference of maximum performance frequency clock count
97  *			read from MPERF MSR between last and current sample
98  * @tsc:		Difference of time stamp counter between last and
99  *			current sample
100  * @time:		Current time from scheduler
101  *
102  * This structure is used in the cpudata structure to store performance sample
103  * data for choosing next P State.
104  */
105 struct sample {
106 	int32_t core_avg_perf;
107 	int32_t busy_scaled;
108 	u64 aperf;
109 	u64 mperf;
110 	u64 tsc;
111 	u64 time;
112 };
113 
114 /**
115  * struct pstate_data - Store P state data
116  * @current_pstate:	Current requested P state
117  * @min_pstate:		Min P state possible for this platform
118  * @max_pstate:		Max P state possible for this platform
119  * @max_pstate_physical:This is physical Max P state for a processor
120  *			This can be higher than the max_pstate which can
121  *			be limited by platform thermal design power limits
122  * @scaling:		Scaling factor to  convert frequency to cpufreq
123  *			frequency units
124  * @turbo_pstate:	Max Turbo P state possible for this platform
125  *
126  * Stores the per cpu model P state limits and current P state.
127  */
128 struct pstate_data {
129 	int	current_pstate;
130 	int	min_pstate;
131 	int	max_pstate;
132 	int	max_pstate_physical;
133 	int	scaling;
134 	int	turbo_pstate;
135 };
136 
137 /**
138  * struct vid_data -	Stores voltage information data
139  * @min:		VID data for this platform corresponding to
140  *			the lowest P state
141  * @max:		VID data corresponding to the highest P State.
142  * @turbo:		VID data for turbo P state
143  * @ratio:		Ratio of (vid max - vid min) /
144  *			(max P state - Min P State)
145  *
146  * Stores the voltage data for DVFS (Dynamic Voltage and Frequency Scaling)
147  * This data is used in Atom platforms, where in addition to target P state,
148  * the voltage data needs to be specified to select next P State.
149  */
150 struct vid_data {
151 	int min;
152 	int max;
153 	int turbo;
154 	int32_t ratio;
155 };
156 
157 /**
158  * struct _pid -	Stores PID data
159  * @setpoint:		Target set point for busyness or performance
160  * @integral:		Storage for accumulated error values
161  * @p_gain:		PID proportional gain
162  * @i_gain:		PID integral gain
163  * @d_gain:		PID derivative gain
164  * @deadband:		PID deadband
165  * @last_err:		Last error storage for integral part of PID calculation
166  *
167  * Stores PID coefficients and last error for PID controller.
168  */
169 struct _pid {
170 	int setpoint;
171 	int32_t integral;
172 	int32_t p_gain;
173 	int32_t i_gain;
174 	int32_t d_gain;
175 	int deadband;
176 	int32_t last_err;
177 };
178 
179 /**
180  * struct cpudata -	Per CPU instance data storage
181  * @cpu:		CPU number for this instance data
182  * @policy:		CPUFreq policy value
183  * @update_util:	CPUFreq utility callback information
184  * @update_util_set:	CPUFreq utility callback is set
185  * @iowait_boost:	iowait-related boost fraction
186  * @last_update:	Time of the last update.
187  * @pstate:		Stores P state limits for this CPU
188  * @vid:		Stores VID limits for this CPU
189  * @pid:		Stores PID parameters for this CPU
190  * @last_sample_time:	Last Sample time
191  * @prev_aperf:		Last APERF value read from APERF MSR
192  * @prev_mperf:		Last MPERF value read from MPERF MSR
193  * @prev_tsc:		Last timestamp counter (TSC) value
194  * @prev_cummulative_iowait: IO Wait time difference from last and
195  *			current sample
196  * @sample:		Storage for storing last Sample data
197  * @acpi_perf_data:	Stores ACPI perf information read from _PSS
198  * @valid_pss_table:	Set to true for valid ACPI _PSS entries found
199  *
200  * This structure stores per CPU instance data for all CPUs.
201  */
202 struct cpudata {
203 	int cpu;
204 
205 	unsigned int policy;
206 	struct update_util_data update_util;
207 	bool   update_util_set;
208 
209 	struct pstate_data pstate;
210 	struct vid_data vid;
211 	struct _pid pid;
212 
213 	u64	last_update;
214 	u64	last_sample_time;
215 	u64	prev_aperf;
216 	u64	prev_mperf;
217 	u64	prev_tsc;
218 	u64	prev_cummulative_iowait;
219 	struct sample sample;
220 #ifdef CONFIG_ACPI
221 	struct acpi_processor_performance acpi_perf_data;
222 	bool valid_pss_table;
223 #endif
224 	unsigned int iowait_boost;
225 };
226 
227 static struct cpudata **all_cpu_data;
228 
229 /**
230  * struct pstate_adjust_policy - Stores static PID configuration data
231  * @sample_rate_ms:	PID calculation sample rate in ms
232  * @sample_rate_ns:	Sample rate calculation in ns
233  * @deadband:		PID deadband
234  * @setpoint:		PID Setpoint
235  * @p_gain_pct:		PID proportional gain
236  * @i_gain_pct:		PID integral gain
237  * @d_gain_pct:		PID derivative gain
238  * @boost_iowait:	Whether or not to use iowait boosting.
239  *
240  * Stores per CPU model static PID configuration data.
241  */
242 struct pstate_adjust_policy {
243 	int sample_rate_ms;
244 	s64 sample_rate_ns;
245 	int deadband;
246 	int setpoint;
247 	int p_gain_pct;
248 	int d_gain_pct;
249 	int i_gain_pct;
250 	bool boost_iowait;
251 };
252 
253 /**
254  * struct pstate_funcs - Per CPU model specific callbacks
255  * @get_max:		Callback to get maximum non turbo effective P state
256  * @get_max_physical:	Callback to get maximum non turbo physical P state
257  * @get_min:		Callback to get minimum P state
258  * @get_turbo:		Callback to get turbo P state
259  * @get_scaling:	Callback to get frequency scaling factor
260  * @get_val:		Callback to convert P state to actual MSR write value
261  * @get_vid:		Callback to get VID data for Atom platforms
262  * @get_target_pstate:	Callback to a function to calculate next P state to use
263  *
264  * Core and Atom CPU models have different way to get P State limits. This
265  * structure is used to store those callbacks.
266  */
267 struct pstate_funcs {
268 	int (*get_max)(void);
269 	int (*get_max_physical)(void);
270 	int (*get_min)(void);
271 	int (*get_turbo)(void);
272 	int (*get_scaling)(void);
273 	u64 (*get_val)(struct cpudata*, int pstate);
274 	void (*get_vid)(struct cpudata *);
275 	int32_t (*get_target_pstate)(struct cpudata *);
276 };
277 
278 /**
279  * struct cpu_defaults- Per CPU model default config data
280  * @pid_policy:	PID config data
281  * @funcs:		Callback function data
282  */
283 struct cpu_defaults {
284 	struct pstate_adjust_policy pid_policy;
285 	struct pstate_funcs funcs;
286 };
287 
288 static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu);
289 static inline int32_t get_target_pstate_use_cpu_load(struct cpudata *cpu);
290 
291 static struct pstate_adjust_policy pid_params __read_mostly;
292 static struct pstate_funcs pstate_funcs __read_mostly;
293 static int hwp_active __read_mostly;
294 
295 #ifdef CONFIG_ACPI
296 static bool acpi_ppc;
297 #endif
298 
299 /**
300  * struct perf_limits - Store user and policy limits
301  * @no_turbo:		User requested turbo state from intel_pstate sysfs
302  * @turbo_disabled:	Platform turbo status either from msr
303  *			MSR_IA32_MISC_ENABLE or when maximum available pstate
304  *			matches the maximum turbo pstate
305  * @max_perf_pct:	Effective maximum performance limit in percentage, this
306  *			is minimum of either limits enforced by cpufreq policy
307  *			or limits from user set limits via intel_pstate sysfs
308  * @min_perf_pct:	Effective minimum performance limit in percentage, this
309  *			is maximum of either limits enforced by cpufreq policy
310  *			or limits from user set limits via intel_pstate sysfs
311  * @max_perf:		This is a scaled value between 0 to 255 for max_perf_pct
312  *			This value is used to limit max pstate
313  * @min_perf:		This is a scaled value between 0 to 255 for min_perf_pct
314  *			This value is used to limit min pstate
315  * @max_policy_pct:	The maximum performance in percentage enforced by
316  *			cpufreq setpolicy interface
317  * @max_sysfs_pct:	The maximum performance in percentage enforced by
318  *			intel pstate sysfs interface
319  * @min_policy_pct:	The minimum performance in percentage enforced by
320  *			cpufreq setpolicy interface
321  * @min_sysfs_pct:	The minimum performance in percentage enforced by
322  *			intel pstate sysfs interface
323  *
324  * Storage for user and policy defined limits.
325  */
326 struct perf_limits {
327 	int no_turbo;
328 	int turbo_disabled;
329 	int max_perf_pct;
330 	int min_perf_pct;
331 	int32_t max_perf;
332 	int32_t min_perf;
333 	int max_policy_pct;
334 	int max_sysfs_pct;
335 	int min_policy_pct;
336 	int min_sysfs_pct;
337 };
338 
339 static struct perf_limits performance_limits = {
340 	.no_turbo = 0,
341 	.turbo_disabled = 0,
342 	.max_perf_pct = 100,
343 	.max_perf = int_tofp(1),
344 	.min_perf_pct = 100,
345 	.min_perf = int_tofp(1),
346 	.max_policy_pct = 100,
347 	.max_sysfs_pct = 100,
348 	.min_policy_pct = 0,
349 	.min_sysfs_pct = 0,
350 };
351 
352 static struct perf_limits powersave_limits = {
353 	.no_turbo = 0,
354 	.turbo_disabled = 0,
355 	.max_perf_pct = 100,
356 	.max_perf = int_tofp(1),
357 	.min_perf_pct = 0,
358 	.min_perf = 0,
359 	.max_policy_pct = 100,
360 	.max_sysfs_pct = 100,
361 	.min_policy_pct = 0,
362 	.min_sysfs_pct = 0,
363 };
364 
365 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
366 static struct perf_limits *limits = &performance_limits;
367 #else
368 static struct perf_limits *limits = &powersave_limits;
369 #endif
370 
371 #ifdef CONFIG_ACPI
372 
373 static bool intel_pstate_get_ppc_enable_status(void)
374 {
375 	if (acpi_gbl_FADT.preferred_profile == PM_ENTERPRISE_SERVER ||
376 	    acpi_gbl_FADT.preferred_profile == PM_PERFORMANCE_SERVER)
377 		return true;
378 
379 	return acpi_ppc;
380 }
381 
382 static void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy)
383 {
384 	struct cpudata *cpu;
385 	int ret;
386 	int i;
387 
388 	if (hwp_active)
389 		return;
390 
391 	if (!intel_pstate_get_ppc_enable_status())
392 		return;
393 
394 	cpu = all_cpu_data[policy->cpu];
395 
396 	ret = acpi_processor_register_performance(&cpu->acpi_perf_data,
397 						  policy->cpu);
398 	if (ret)
399 		return;
400 
401 	/*
402 	 * Check if the control value in _PSS is for PERF_CTL MSR, which should
403 	 * guarantee that the states returned by it map to the states in our
404 	 * list directly.
405 	 */
406 	if (cpu->acpi_perf_data.control_register.space_id !=
407 						ACPI_ADR_SPACE_FIXED_HARDWARE)
408 		goto err;
409 
410 	/*
411 	 * If there is only one entry _PSS, simply ignore _PSS and continue as
412 	 * usual without taking _PSS into account
413 	 */
414 	if (cpu->acpi_perf_data.state_count < 2)
415 		goto err;
416 
417 	pr_debug("CPU%u - ACPI _PSS perf data\n", policy->cpu);
418 	for (i = 0; i < cpu->acpi_perf_data.state_count; i++) {
419 		pr_debug("     %cP%d: %u MHz, %u mW, 0x%x\n",
420 			 (i == cpu->acpi_perf_data.state ? '*' : ' '), i,
421 			 (u32) cpu->acpi_perf_data.states[i].core_frequency,
422 			 (u32) cpu->acpi_perf_data.states[i].power,
423 			 (u32) cpu->acpi_perf_data.states[i].control);
424 	}
425 
426 	/*
427 	 * The _PSS table doesn't contain whole turbo frequency range.
428 	 * This just contains +1 MHZ above the max non turbo frequency,
429 	 * with control value corresponding to max turbo ratio. But
430 	 * when cpufreq set policy is called, it will call with this
431 	 * max frequency, which will cause a reduced performance as
432 	 * this driver uses real max turbo frequency as the max
433 	 * frequency. So correct this frequency in _PSS table to
434 	 * correct max turbo frequency based on the turbo state.
435 	 * Also need to convert to MHz as _PSS freq is in MHz.
436 	 */
437 	if (!limits->turbo_disabled)
438 		cpu->acpi_perf_data.states[0].core_frequency =
439 					policy->cpuinfo.max_freq / 1000;
440 	cpu->valid_pss_table = true;
441 	pr_debug("_PPC limits will be enforced\n");
442 
443 	return;
444 
445  err:
446 	cpu->valid_pss_table = false;
447 	acpi_processor_unregister_performance(policy->cpu);
448 }
449 
450 static void intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
451 {
452 	struct cpudata *cpu;
453 
454 	cpu = all_cpu_data[policy->cpu];
455 	if (!cpu->valid_pss_table)
456 		return;
457 
458 	acpi_processor_unregister_performance(policy->cpu);
459 }
460 
461 #else
462 static void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy)
463 {
464 }
465 
466 static void intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
467 {
468 }
469 #endif
470 
471 static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
472 			     int deadband, int integral) {
473 	pid->setpoint = int_tofp(setpoint);
474 	pid->deadband  = int_tofp(deadband);
475 	pid->integral  = int_tofp(integral);
476 	pid->last_err  = int_tofp(setpoint) - int_tofp(busy);
477 }
478 
479 static inline void pid_p_gain_set(struct _pid *pid, int percent)
480 {
481 	pid->p_gain = div_fp(percent, 100);
482 }
483 
484 static inline void pid_i_gain_set(struct _pid *pid, int percent)
485 {
486 	pid->i_gain = div_fp(percent, 100);
487 }
488 
489 static inline void pid_d_gain_set(struct _pid *pid, int percent)
490 {
491 	pid->d_gain = div_fp(percent, 100);
492 }
493 
494 static signed int pid_calc(struct _pid *pid, int32_t busy)
495 {
496 	signed int result;
497 	int32_t pterm, dterm, fp_error;
498 	int32_t integral_limit;
499 
500 	fp_error = pid->setpoint - busy;
501 
502 	if (abs(fp_error) <= pid->deadband)
503 		return 0;
504 
505 	pterm = mul_fp(pid->p_gain, fp_error);
506 
507 	pid->integral += fp_error;
508 
509 	/*
510 	 * We limit the integral here so that it will never
511 	 * get higher than 30.  This prevents it from becoming
512 	 * too large an input over long periods of time and allows
513 	 * it to get factored out sooner.
514 	 *
515 	 * The value of 30 was chosen through experimentation.
516 	 */
517 	integral_limit = int_tofp(30);
518 	if (pid->integral > integral_limit)
519 		pid->integral = integral_limit;
520 	if (pid->integral < -integral_limit)
521 		pid->integral = -integral_limit;
522 
523 	dterm = mul_fp(pid->d_gain, fp_error - pid->last_err);
524 	pid->last_err = fp_error;
525 
526 	result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm;
527 	result = result + (1 << (FRAC_BITS-1));
528 	return (signed int)fp_toint(result);
529 }
530 
531 static inline void intel_pstate_busy_pid_reset(struct cpudata *cpu)
532 {
533 	pid_p_gain_set(&cpu->pid, pid_params.p_gain_pct);
534 	pid_d_gain_set(&cpu->pid, pid_params.d_gain_pct);
535 	pid_i_gain_set(&cpu->pid, pid_params.i_gain_pct);
536 
537 	pid_reset(&cpu->pid, pid_params.setpoint, 100, pid_params.deadband, 0);
538 }
539 
540 static inline void intel_pstate_reset_all_pid(void)
541 {
542 	unsigned int cpu;
543 
544 	for_each_online_cpu(cpu) {
545 		if (all_cpu_data[cpu])
546 			intel_pstate_busy_pid_reset(all_cpu_data[cpu]);
547 	}
548 }
549 
550 static inline void update_turbo_state(void)
551 {
552 	u64 misc_en;
553 	struct cpudata *cpu;
554 
555 	cpu = all_cpu_data[0];
556 	rdmsrl(MSR_IA32_MISC_ENABLE, misc_en);
557 	limits->turbo_disabled =
558 		(misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE ||
559 		 cpu->pstate.max_pstate == cpu->pstate.turbo_pstate);
560 }
561 
562 static void intel_pstate_hwp_set(const struct cpumask *cpumask)
563 {
564 	int min, hw_min, max, hw_max, cpu, range, adj_range;
565 	u64 value, cap;
566 
567 	for_each_cpu(cpu, cpumask) {
568 		rdmsrl_on_cpu(cpu, MSR_HWP_CAPABILITIES, &cap);
569 		hw_min = HWP_LOWEST_PERF(cap);
570 		hw_max = HWP_HIGHEST_PERF(cap);
571 		range = hw_max - hw_min;
572 
573 		rdmsrl_on_cpu(cpu, MSR_HWP_REQUEST, &value);
574 		adj_range = limits->min_perf_pct * range / 100;
575 		min = hw_min + adj_range;
576 		value &= ~HWP_MIN_PERF(~0L);
577 		value |= HWP_MIN_PERF(min);
578 
579 		adj_range = limits->max_perf_pct * range / 100;
580 		max = hw_min + adj_range;
581 		if (limits->no_turbo) {
582 			hw_max = HWP_GUARANTEED_PERF(cap);
583 			if (hw_max < max)
584 				max = hw_max;
585 		}
586 
587 		value &= ~HWP_MAX_PERF(~0L);
588 		value |= HWP_MAX_PERF(max);
589 		wrmsrl_on_cpu(cpu, MSR_HWP_REQUEST, value);
590 	}
591 }
592 
593 static int intel_pstate_hwp_set_policy(struct cpufreq_policy *policy)
594 {
595 	if (hwp_active)
596 		intel_pstate_hwp_set(policy->cpus);
597 
598 	return 0;
599 }
600 
601 static void intel_pstate_hwp_set_online_cpus(void)
602 {
603 	get_online_cpus();
604 	intel_pstate_hwp_set(cpu_online_mask);
605 	put_online_cpus();
606 }
607 
608 /************************** debugfs begin ************************/
609 static int pid_param_set(void *data, u64 val)
610 {
611 	*(u32 *)data = val;
612 	intel_pstate_reset_all_pid();
613 	return 0;
614 }
615 
616 static int pid_param_get(void *data, u64 *val)
617 {
618 	*val = *(u32 *)data;
619 	return 0;
620 }
621 DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get, pid_param_set, "%llu\n");
622 
623 struct pid_param {
624 	char *name;
625 	void *value;
626 };
627 
628 static struct pid_param pid_files[] = {
629 	{"sample_rate_ms", &pid_params.sample_rate_ms},
630 	{"d_gain_pct", &pid_params.d_gain_pct},
631 	{"i_gain_pct", &pid_params.i_gain_pct},
632 	{"deadband", &pid_params.deadband},
633 	{"setpoint", &pid_params.setpoint},
634 	{"p_gain_pct", &pid_params.p_gain_pct},
635 	{NULL, NULL}
636 };
637 
638 static void __init intel_pstate_debug_expose_params(void)
639 {
640 	struct dentry *debugfs_parent;
641 	int i = 0;
642 
643 	if (hwp_active)
644 		return;
645 	debugfs_parent = debugfs_create_dir("pstate_snb", NULL);
646 	if (IS_ERR_OR_NULL(debugfs_parent))
647 		return;
648 	while (pid_files[i].name) {
649 		debugfs_create_file(pid_files[i].name, 0660,
650 				    debugfs_parent, pid_files[i].value,
651 				    &fops_pid_param);
652 		i++;
653 	}
654 }
655 
656 /************************** debugfs end ************************/
657 
658 /************************** sysfs begin ************************/
659 #define show_one(file_name, object)					\
660 	static ssize_t show_##file_name					\
661 	(struct kobject *kobj, struct attribute *attr, char *buf)	\
662 	{								\
663 		return sprintf(buf, "%u\n", limits->object);		\
664 	}
665 
666 static ssize_t show_turbo_pct(struct kobject *kobj,
667 				struct attribute *attr, char *buf)
668 {
669 	struct cpudata *cpu;
670 	int total, no_turbo, turbo_pct;
671 	uint32_t turbo_fp;
672 
673 	cpu = all_cpu_data[0];
674 
675 	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
676 	no_turbo = cpu->pstate.max_pstate - cpu->pstate.min_pstate + 1;
677 	turbo_fp = div_fp(no_turbo, total);
678 	turbo_pct = 100 - fp_toint(mul_fp(turbo_fp, int_tofp(100)));
679 	return sprintf(buf, "%u\n", turbo_pct);
680 }
681 
682 static ssize_t show_num_pstates(struct kobject *kobj,
683 				struct attribute *attr, char *buf)
684 {
685 	struct cpudata *cpu;
686 	int total;
687 
688 	cpu = all_cpu_data[0];
689 	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
690 	return sprintf(buf, "%u\n", total);
691 }
692 
693 static ssize_t show_no_turbo(struct kobject *kobj,
694 			     struct attribute *attr, char *buf)
695 {
696 	ssize_t ret;
697 
698 	update_turbo_state();
699 	if (limits->turbo_disabled)
700 		ret = sprintf(buf, "%u\n", limits->turbo_disabled);
701 	else
702 		ret = sprintf(buf, "%u\n", limits->no_turbo);
703 
704 	return ret;
705 }
706 
707 static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
708 			      const char *buf, size_t count)
709 {
710 	unsigned int input;
711 	int ret;
712 
713 	ret = sscanf(buf, "%u", &input);
714 	if (ret != 1)
715 		return -EINVAL;
716 
717 	update_turbo_state();
718 	if (limits->turbo_disabled) {
719 		pr_warn("Turbo disabled by BIOS or unavailable on processor\n");
720 		return -EPERM;
721 	}
722 
723 	limits->no_turbo = clamp_t(int, input, 0, 1);
724 
725 	if (hwp_active)
726 		intel_pstate_hwp_set_online_cpus();
727 
728 	return count;
729 }
730 
731 static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
732 				  const char *buf, size_t count)
733 {
734 	unsigned int input;
735 	int ret;
736 
737 	ret = sscanf(buf, "%u", &input);
738 	if (ret != 1)
739 		return -EINVAL;
740 
741 	limits->max_sysfs_pct = clamp_t(int, input, 0 , 100);
742 	limits->max_perf_pct = min(limits->max_policy_pct,
743 				   limits->max_sysfs_pct);
744 	limits->max_perf_pct = max(limits->min_policy_pct,
745 				   limits->max_perf_pct);
746 	limits->max_perf_pct = max(limits->min_perf_pct,
747 				   limits->max_perf_pct);
748 	limits->max_perf = div_fp(limits->max_perf_pct, 100);
749 
750 	if (hwp_active)
751 		intel_pstate_hwp_set_online_cpus();
752 	return count;
753 }
754 
755 static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
756 				  const char *buf, size_t count)
757 {
758 	unsigned int input;
759 	int ret;
760 
761 	ret = sscanf(buf, "%u", &input);
762 	if (ret != 1)
763 		return -EINVAL;
764 
765 	limits->min_sysfs_pct = clamp_t(int, input, 0 , 100);
766 	limits->min_perf_pct = max(limits->min_policy_pct,
767 				   limits->min_sysfs_pct);
768 	limits->min_perf_pct = min(limits->max_policy_pct,
769 				   limits->min_perf_pct);
770 	limits->min_perf_pct = min(limits->max_perf_pct,
771 				   limits->min_perf_pct);
772 	limits->min_perf = div_fp(limits->min_perf_pct, 100);
773 
774 	if (hwp_active)
775 		intel_pstate_hwp_set_online_cpus();
776 	return count;
777 }
778 
779 show_one(max_perf_pct, max_perf_pct);
780 show_one(min_perf_pct, min_perf_pct);
781 
782 define_one_global_rw(no_turbo);
783 define_one_global_rw(max_perf_pct);
784 define_one_global_rw(min_perf_pct);
785 define_one_global_ro(turbo_pct);
786 define_one_global_ro(num_pstates);
787 
788 static struct attribute *intel_pstate_attributes[] = {
789 	&no_turbo.attr,
790 	&max_perf_pct.attr,
791 	&min_perf_pct.attr,
792 	&turbo_pct.attr,
793 	&num_pstates.attr,
794 	NULL
795 };
796 
797 static struct attribute_group intel_pstate_attr_group = {
798 	.attrs = intel_pstate_attributes,
799 };
800 
801 static void __init intel_pstate_sysfs_expose_params(void)
802 {
803 	struct kobject *intel_pstate_kobject;
804 	int rc;
805 
806 	intel_pstate_kobject = kobject_create_and_add("intel_pstate",
807 						&cpu_subsys.dev_root->kobj);
808 	BUG_ON(!intel_pstate_kobject);
809 	rc = sysfs_create_group(intel_pstate_kobject, &intel_pstate_attr_group);
810 	BUG_ON(rc);
811 }
812 /************************** sysfs end ************************/
813 
814 static void intel_pstate_hwp_enable(struct cpudata *cpudata)
815 {
816 	/* First disable HWP notification interrupt as we don't process them */
817 	if (static_cpu_has(X86_FEATURE_HWP_NOTIFY))
818 		wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_INTERRUPT, 0x00);
819 
820 	wrmsrl_on_cpu(cpudata->cpu, MSR_PM_ENABLE, 0x1);
821 }
822 
823 static int atom_get_min_pstate(void)
824 {
825 	u64 value;
826 
827 	rdmsrl(ATOM_RATIOS, value);
828 	return (value >> 8) & 0x7F;
829 }
830 
831 static int atom_get_max_pstate(void)
832 {
833 	u64 value;
834 
835 	rdmsrl(ATOM_RATIOS, value);
836 	return (value >> 16) & 0x7F;
837 }
838 
839 static int atom_get_turbo_pstate(void)
840 {
841 	u64 value;
842 
843 	rdmsrl(ATOM_TURBO_RATIOS, value);
844 	return value & 0x7F;
845 }
846 
847 static u64 atom_get_val(struct cpudata *cpudata, int pstate)
848 {
849 	u64 val;
850 	int32_t vid_fp;
851 	u32 vid;
852 
853 	val = (u64)pstate << 8;
854 	if (limits->no_turbo && !limits->turbo_disabled)
855 		val |= (u64)1 << 32;
856 
857 	vid_fp = cpudata->vid.min + mul_fp(
858 		int_tofp(pstate - cpudata->pstate.min_pstate),
859 		cpudata->vid.ratio);
860 
861 	vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
862 	vid = ceiling_fp(vid_fp);
863 
864 	if (pstate > cpudata->pstate.max_pstate)
865 		vid = cpudata->vid.turbo;
866 
867 	return val | vid;
868 }
869 
870 static int silvermont_get_scaling(void)
871 {
872 	u64 value;
873 	int i;
874 	/* Defined in Table 35-6 from SDM (Sept 2015) */
875 	static int silvermont_freq_table[] = {
876 		83300, 100000, 133300, 116700, 80000};
877 
878 	rdmsrl(MSR_FSB_FREQ, value);
879 	i = value & 0x7;
880 	WARN_ON(i > 4);
881 
882 	return silvermont_freq_table[i];
883 }
884 
885 static int airmont_get_scaling(void)
886 {
887 	u64 value;
888 	int i;
889 	/* Defined in Table 35-10 from SDM (Sept 2015) */
890 	static int airmont_freq_table[] = {
891 		83300, 100000, 133300, 116700, 80000,
892 		93300, 90000, 88900, 87500};
893 
894 	rdmsrl(MSR_FSB_FREQ, value);
895 	i = value & 0xF;
896 	WARN_ON(i > 8);
897 
898 	return airmont_freq_table[i];
899 }
900 
901 static void atom_get_vid(struct cpudata *cpudata)
902 {
903 	u64 value;
904 
905 	rdmsrl(ATOM_VIDS, value);
906 	cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
907 	cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
908 	cpudata->vid.ratio = div_fp(
909 		cpudata->vid.max - cpudata->vid.min,
910 		int_tofp(cpudata->pstate.max_pstate -
911 			cpudata->pstate.min_pstate));
912 
913 	rdmsrl(ATOM_TURBO_VIDS, value);
914 	cpudata->vid.turbo = value & 0x7f;
915 }
916 
917 static int core_get_min_pstate(void)
918 {
919 	u64 value;
920 
921 	rdmsrl(MSR_PLATFORM_INFO, value);
922 	return (value >> 40) & 0xFF;
923 }
924 
925 static int core_get_max_pstate_physical(void)
926 {
927 	u64 value;
928 
929 	rdmsrl(MSR_PLATFORM_INFO, value);
930 	return (value >> 8) & 0xFF;
931 }
932 
933 static int core_get_max_pstate(void)
934 {
935 	u64 tar;
936 	u64 plat_info;
937 	int max_pstate;
938 	int err;
939 
940 	rdmsrl(MSR_PLATFORM_INFO, plat_info);
941 	max_pstate = (plat_info >> 8) & 0xFF;
942 
943 	err = rdmsrl_safe(MSR_TURBO_ACTIVATION_RATIO, &tar);
944 	if (!err) {
945 		/* Do some sanity checking for safety */
946 		if (plat_info & 0x600000000) {
947 			u64 tdp_ctrl;
948 			u64 tdp_ratio;
949 			int tdp_msr;
950 
951 			err = rdmsrl_safe(MSR_CONFIG_TDP_CONTROL, &tdp_ctrl);
952 			if (err)
953 				goto skip_tar;
954 
955 			tdp_msr = MSR_CONFIG_TDP_NOMINAL + (tdp_ctrl & 0x3);
956 			err = rdmsrl_safe(tdp_msr, &tdp_ratio);
957 			if (err)
958 				goto skip_tar;
959 
960 			/* For level 1 and 2, bits[23:16] contain the ratio */
961 			if (tdp_ctrl)
962 				tdp_ratio >>= 16;
963 
964 			tdp_ratio &= 0xff; /* ratios are only 8 bits long */
965 			if (tdp_ratio - 1 == tar) {
966 				max_pstate = tar;
967 				pr_debug("max_pstate=TAC %x\n", max_pstate);
968 			} else {
969 				goto skip_tar;
970 			}
971 		}
972 	}
973 
974 skip_tar:
975 	return max_pstate;
976 }
977 
978 static int core_get_turbo_pstate(void)
979 {
980 	u64 value;
981 	int nont, ret;
982 
983 	rdmsrl(MSR_TURBO_RATIO_LIMIT, value);
984 	nont = core_get_max_pstate();
985 	ret = (value) & 255;
986 	if (ret <= nont)
987 		ret = nont;
988 	return ret;
989 }
990 
991 static inline int core_get_scaling(void)
992 {
993 	return 100000;
994 }
995 
996 static u64 core_get_val(struct cpudata *cpudata, int pstate)
997 {
998 	u64 val;
999 
1000 	val = (u64)pstate << 8;
1001 	if (limits->no_turbo && !limits->turbo_disabled)
1002 		val |= (u64)1 << 32;
1003 
1004 	return val;
1005 }
1006 
1007 static int knl_get_turbo_pstate(void)
1008 {
1009 	u64 value;
1010 	int nont, ret;
1011 
1012 	rdmsrl(MSR_TURBO_RATIO_LIMIT, value);
1013 	nont = core_get_max_pstate();
1014 	ret = (((value) >> 8) & 0xFF);
1015 	if (ret <= nont)
1016 		ret = nont;
1017 	return ret;
1018 }
1019 
1020 static struct cpu_defaults core_params = {
1021 	.pid_policy = {
1022 		.sample_rate_ms = 10,
1023 		.deadband = 0,
1024 		.setpoint = 97,
1025 		.p_gain_pct = 20,
1026 		.d_gain_pct = 0,
1027 		.i_gain_pct = 0,
1028 	},
1029 	.funcs = {
1030 		.get_max = core_get_max_pstate,
1031 		.get_max_physical = core_get_max_pstate_physical,
1032 		.get_min = core_get_min_pstate,
1033 		.get_turbo = core_get_turbo_pstate,
1034 		.get_scaling = core_get_scaling,
1035 		.get_val = core_get_val,
1036 		.get_target_pstate = get_target_pstate_use_performance,
1037 	},
1038 };
1039 
1040 static const struct cpu_defaults silvermont_params = {
1041 	.pid_policy = {
1042 		.sample_rate_ms = 10,
1043 		.deadband = 0,
1044 		.setpoint = 60,
1045 		.p_gain_pct = 14,
1046 		.d_gain_pct = 0,
1047 		.i_gain_pct = 4,
1048 		.boost_iowait = true,
1049 	},
1050 	.funcs = {
1051 		.get_max = atom_get_max_pstate,
1052 		.get_max_physical = atom_get_max_pstate,
1053 		.get_min = atom_get_min_pstate,
1054 		.get_turbo = atom_get_turbo_pstate,
1055 		.get_val = atom_get_val,
1056 		.get_scaling = silvermont_get_scaling,
1057 		.get_vid = atom_get_vid,
1058 		.get_target_pstate = get_target_pstate_use_cpu_load,
1059 	},
1060 };
1061 
1062 static const struct cpu_defaults airmont_params = {
1063 	.pid_policy = {
1064 		.sample_rate_ms = 10,
1065 		.deadband = 0,
1066 		.setpoint = 60,
1067 		.p_gain_pct = 14,
1068 		.d_gain_pct = 0,
1069 		.i_gain_pct = 4,
1070 		.boost_iowait = true,
1071 	},
1072 	.funcs = {
1073 		.get_max = atom_get_max_pstate,
1074 		.get_max_physical = atom_get_max_pstate,
1075 		.get_min = atom_get_min_pstate,
1076 		.get_turbo = atom_get_turbo_pstate,
1077 		.get_val = atom_get_val,
1078 		.get_scaling = airmont_get_scaling,
1079 		.get_vid = atom_get_vid,
1080 		.get_target_pstate = get_target_pstate_use_cpu_load,
1081 	},
1082 };
1083 
1084 static const struct cpu_defaults knl_params = {
1085 	.pid_policy = {
1086 		.sample_rate_ms = 10,
1087 		.deadband = 0,
1088 		.setpoint = 97,
1089 		.p_gain_pct = 20,
1090 		.d_gain_pct = 0,
1091 		.i_gain_pct = 0,
1092 	},
1093 	.funcs = {
1094 		.get_max = core_get_max_pstate,
1095 		.get_max_physical = core_get_max_pstate_physical,
1096 		.get_min = core_get_min_pstate,
1097 		.get_turbo = knl_get_turbo_pstate,
1098 		.get_scaling = core_get_scaling,
1099 		.get_val = core_get_val,
1100 		.get_target_pstate = get_target_pstate_use_performance,
1101 	},
1102 };
1103 
1104 static const struct cpu_defaults bxt_params = {
1105 	.pid_policy = {
1106 		.sample_rate_ms = 10,
1107 		.deadband = 0,
1108 		.setpoint = 60,
1109 		.p_gain_pct = 14,
1110 		.d_gain_pct = 0,
1111 		.i_gain_pct = 4,
1112 		.boost_iowait = true,
1113 	},
1114 	.funcs = {
1115 		.get_max = core_get_max_pstate,
1116 		.get_max_physical = core_get_max_pstate_physical,
1117 		.get_min = core_get_min_pstate,
1118 		.get_turbo = core_get_turbo_pstate,
1119 		.get_scaling = core_get_scaling,
1120 		.get_val = core_get_val,
1121 		.get_target_pstate = get_target_pstate_use_cpu_load,
1122 	},
1123 };
1124 
1125 static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max)
1126 {
1127 	int max_perf = cpu->pstate.turbo_pstate;
1128 	int max_perf_adj;
1129 	int min_perf;
1130 
1131 	if (limits->no_turbo || limits->turbo_disabled)
1132 		max_perf = cpu->pstate.max_pstate;
1133 
1134 	/*
1135 	 * performance can be limited by user through sysfs, by cpufreq
1136 	 * policy, or by cpu specific default values determined through
1137 	 * experimentation.
1138 	 */
1139 	max_perf_adj = fp_toint(max_perf * limits->max_perf);
1140 	*max = clamp_t(int, max_perf_adj,
1141 			cpu->pstate.min_pstate, cpu->pstate.turbo_pstate);
1142 
1143 	min_perf = fp_toint(max_perf * limits->min_perf);
1144 	*min = clamp_t(int, min_perf, cpu->pstate.min_pstate, max_perf);
1145 }
1146 
1147 static void intel_pstate_set_pstate(struct cpudata *cpu, int pstate)
1148 {
1149 	trace_cpu_frequency(pstate * cpu->pstate.scaling, cpu->cpu);
1150 	cpu->pstate.current_pstate = pstate;
1151 	/*
1152 	 * Generally, there is no guarantee that this code will always run on
1153 	 * the CPU being updated, so force the register update to run on the
1154 	 * right CPU.
1155 	 */
1156 	wrmsrl_on_cpu(cpu->cpu, MSR_IA32_PERF_CTL,
1157 		      pstate_funcs.get_val(cpu, pstate));
1158 }
1159 
1160 static void intel_pstate_set_min_pstate(struct cpudata *cpu)
1161 {
1162 	intel_pstate_set_pstate(cpu, cpu->pstate.min_pstate);
1163 }
1164 
1165 static void intel_pstate_max_within_limits(struct cpudata *cpu)
1166 {
1167 	int min_pstate, max_pstate;
1168 
1169 	update_turbo_state();
1170 	intel_pstate_get_min_max(cpu, &min_pstate, &max_pstate);
1171 	intel_pstate_set_pstate(cpu, max_pstate);
1172 }
1173 
1174 static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
1175 {
1176 	cpu->pstate.min_pstate = pstate_funcs.get_min();
1177 	cpu->pstate.max_pstate = pstate_funcs.get_max();
1178 	cpu->pstate.max_pstate_physical = pstate_funcs.get_max_physical();
1179 	cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
1180 	cpu->pstate.scaling = pstate_funcs.get_scaling();
1181 
1182 	if (pstate_funcs.get_vid)
1183 		pstate_funcs.get_vid(cpu);
1184 
1185 	intel_pstate_set_min_pstate(cpu);
1186 }
1187 
1188 static inline void intel_pstate_calc_avg_perf(struct cpudata *cpu)
1189 {
1190 	struct sample *sample = &cpu->sample;
1191 
1192 	sample->core_avg_perf = div_ext_fp(sample->aperf, sample->mperf);
1193 }
1194 
1195 static inline bool intel_pstate_sample(struct cpudata *cpu, u64 time)
1196 {
1197 	u64 aperf, mperf;
1198 	unsigned long flags;
1199 	u64 tsc;
1200 
1201 	local_irq_save(flags);
1202 	rdmsrl(MSR_IA32_APERF, aperf);
1203 	rdmsrl(MSR_IA32_MPERF, mperf);
1204 	tsc = rdtsc();
1205 	if (cpu->prev_mperf == mperf || cpu->prev_tsc == tsc) {
1206 		local_irq_restore(flags);
1207 		return false;
1208 	}
1209 	local_irq_restore(flags);
1210 
1211 	cpu->last_sample_time = cpu->sample.time;
1212 	cpu->sample.time = time;
1213 	cpu->sample.aperf = aperf;
1214 	cpu->sample.mperf = mperf;
1215 	cpu->sample.tsc =  tsc;
1216 	cpu->sample.aperf -= cpu->prev_aperf;
1217 	cpu->sample.mperf -= cpu->prev_mperf;
1218 	cpu->sample.tsc -= cpu->prev_tsc;
1219 
1220 	cpu->prev_aperf = aperf;
1221 	cpu->prev_mperf = mperf;
1222 	cpu->prev_tsc = tsc;
1223 	/*
1224 	 * First time this function is invoked in a given cycle, all of the
1225 	 * previous sample data fields are equal to zero or stale and they must
1226 	 * be populated with meaningful numbers for things to work, so assume
1227 	 * that sample.time will always be reset before setting the utilization
1228 	 * update hook and make the caller skip the sample then.
1229 	 */
1230 	return !!cpu->last_sample_time;
1231 }
1232 
1233 static inline int32_t get_avg_frequency(struct cpudata *cpu)
1234 {
1235 	return mul_ext_fp(cpu->sample.core_avg_perf,
1236 			  cpu->pstate.max_pstate_physical * cpu->pstate.scaling);
1237 }
1238 
1239 static inline int32_t get_avg_pstate(struct cpudata *cpu)
1240 {
1241 	return mul_ext_fp(cpu->pstate.max_pstate_physical,
1242 			  cpu->sample.core_avg_perf);
1243 }
1244 
1245 static inline int32_t get_target_pstate_use_cpu_load(struct cpudata *cpu)
1246 {
1247 	struct sample *sample = &cpu->sample;
1248 	int32_t busy_frac, boost;
1249 	int target, avg_pstate;
1250 
1251 	busy_frac = div_fp(sample->mperf, sample->tsc);
1252 
1253 	boost = cpu->iowait_boost;
1254 	cpu->iowait_boost >>= 1;
1255 
1256 	if (busy_frac < boost)
1257 		busy_frac = boost;
1258 
1259 	sample->busy_scaled = busy_frac * 100;
1260 
1261 	target = limits->no_turbo || limits->turbo_disabled ?
1262 			cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
1263 	target += target >> 2;
1264 	target = mul_fp(target, busy_frac);
1265 	if (target < cpu->pstate.min_pstate)
1266 		target = cpu->pstate.min_pstate;
1267 
1268 	/*
1269 	 * If the average P-state during the previous cycle was higher than the
1270 	 * current target, add 50% of the difference to the target to reduce
1271 	 * possible performance oscillations and offset possible performance
1272 	 * loss related to moving the workload from one CPU to another within
1273 	 * a package/module.
1274 	 */
1275 	avg_pstate = get_avg_pstate(cpu);
1276 	if (avg_pstate > target)
1277 		target += (avg_pstate - target) >> 1;
1278 
1279 	return target;
1280 }
1281 
1282 static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu)
1283 {
1284 	int32_t perf_scaled, max_pstate, current_pstate, sample_ratio;
1285 	u64 duration_ns;
1286 
1287 	/*
1288 	 * perf_scaled is the ratio of the average P-state during the last
1289 	 * sampling period to the P-state requested last time (in percent).
1290 	 *
1291 	 * That measures the system's response to the previous P-state
1292 	 * selection.
1293 	 */
1294 	max_pstate = cpu->pstate.max_pstate_physical;
1295 	current_pstate = cpu->pstate.current_pstate;
1296 	perf_scaled = mul_ext_fp(cpu->sample.core_avg_perf,
1297 			       div_fp(100 * max_pstate, current_pstate));
1298 
1299 	/*
1300 	 * Since our utilization update callback will not run unless we are
1301 	 * in C0, check if the actual elapsed time is significantly greater (3x)
1302 	 * than our sample interval.  If it is, then we were idle for a long
1303 	 * enough period of time to adjust our performance metric.
1304 	 */
1305 	duration_ns = cpu->sample.time - cpu->last_sample_time;
1306 	if ((s64)duration_ns > pid_params.sample_rate_ns * 3) {
1307 		sample_ratio = div_fp(pid_params.sample_rate_ns, duration_ns);
1308 		perf_scaled = mul_fp(perf_scaled, sample_ratio);
1309 	} else {
1310 		sample_ratio = div_fp(100 * cpu->sample.mperf, cpu->sample.tsc);
1311 		if (sample_ratio < int_tofp(1))
1312 			perf_scaled = 0;
1313 	}
1314 
1315 	cpu->sample.busy_scaled = perf_scaled;
1316 	return cpu->pstate.current_pstate - pid_calc(&cpu->pid, perf_scaled);
1317 }
1318 
1319 static inline void intel_pstate_update_pstate(struct cpudata *cpu, int pstate)
1320 {
1321 	int max_perf, min_perf;
1322 
1323 	update_turbo_state();
1324 
1325 	intel_pstate_get_min_max(cpu, &min_perf, &max_perf);
1326 	pstate = clamp_t(int, pstate, min_perf, max_perf);
1327 	trace_cpu_frequency(pstate * cpu->pstate.scaling, cpu->cpu);
1328 	if (pstate == cpu->pstate.current_pstate)
1329 		return;
1330 
1331 	cpu->pstate.current_pstate = pstate;
1332 	wrmsrl(MSR_IA32_PERF_CTL, pstate_funcs.get_val(cpu, pstate));
1333 }
1334 
1335 static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
1336 {
1337 	int from, target_pstate;
1338 	struct sample *sample;
1339 
1340 	from = cpu->pstate.current_pstate;
1341 
1342 	target_pstate = cpu->policy == CPUFREQ_POLICY_PERFORMANCE ?
1343 		cpu->pstate.turbo_pstate : pstate_funcs.get_target_pstate(cpu);
1344 
1345 	intel_pstate_update_pstate(cpu, target_pstate);
1346 
1347 	sample = &cpu->sample;
1348 	trace_pstate_sample(mul_ext_fp(100, sample->core_avg_perf),
1349 		fp_toint(sample->busy_scaled),
1350 		from,
1351 		cpu->pstate.current_pstate,
1352 		sample->mperf,
1353 		sample->aperf,
1354 		sample->tsc,
1355 		get_avg_frequency(cpu),
1356 		fp_toint(cpu->iowait_boost * 100));
1357 }
1358 
1359 static void intel_pstate_update_util(struct update_util_data *data, u64 time,
1360 				     unsigned int flags)
1361 {
1362 	struct cpudata *cpu = container_of(data, struct cpudata, update_util);
1363 	u64 delta_ns;
1364 
1365 	if (pid_params.boost_iowait) {
1366 		if (flags & SCHED_CPUFREQ_IOWAIT) {
1367 			cpu->iowait_boost = int_tofp(1);
1368 		} else if (cpu->iowait_boost) {
1369 			/* Clear iowait_boost if the CPU may have been idle. */
1370 			delta_ns = time - cpu->last_update;
1371 			if (delta_ns > TICK_NSEC)
1372 				cpu->iowait_boost = 0;
1373 		}
1374 		cpu->last_update = time;
1375 	}
1376 
1377 	delta_ns = time - cpu->sample.time;
1378 	if ((s64)delta_ns >= pid_params.sample_rate_ns) {
1379 		bool sample_taken = intel_pstate_sample(cpu, time);
1380 
1381 		if (sample_taken) {
1382 			intel_pstate_calc_avg_perf(cpu);
1383 			if (!hwp_active)
1384 				intel_pstate_adjust_busy_pstate(cpu);
1385 		}
1386 	}
1387 }
1388 
1389 #define ICPU(model, policy) \
1390 	{ X86_VENDOR_INTEL, 6, model, X86_FEATURE_APERFMPERF,\
1391 			(unsigned long)&policy }
1392 
1393 static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
1394 	ICPU(INTEL_FAM6_SANDYBRIDGE, 		core_params),
1395 	ICPU(INTEL_FAM6_SANDYBRIDGE_X,		core_params),
1396 	ICPU(INTEL_FAM6_ATOM_SILVERMONT1,	silvermont_params),
1397 	ICPU(INTEL_FAM6_IVYBRIDGE,		core_params),
1398 	ICPU(INTEL_FAM6_HASWELL_CORE,		core_params),
1399 	ICPU(INTEL_FAM6_BROADWELL_CORE,		core_params),
1400 	ICPU(INTEL_FAM6_IVYBRIDGE_X,		core_params),
1401 	ICPU(INTEL_FAM6_HASWELL_X,		core_params),
1402 	ICPU(INTEL_FAM6_HASWELL_ULT,		core_params),
1403 	ICPU(INTEL_FAM6_HASWELL_GT3E,		core_params),
1404 	ICPU(INTEL_FAM6_BROADWELL_GT3E,		core_params),
1405 	ICPU(INTEL_FAM6_ATOM_AIRMONT,		airmont_params),
1406 	ICPU(INTEL_FAM6_SKYLAKE_MOBILE,		core_params),
1407 	ICPU(INTEL_FAM6_BROADWELL_X,		core_params),
1408 	ICPU(INTEL_FAM6_SKYLAKE_DESKTOP,	core_params),
1409 	ICPU(INTEL_FAM6_BROADWELL_XEON_D,	core_params),
1410 	ICPU(INTEL_FAM6_XEON_PHI_KNL,		knl_params),
1411 	ICPU(INTEL_FAM6_ATOM_GOLDMONT,		bxt_params),
1412 	{}
1413 };
1414 MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
1415 
1416 static const struct x86_cpu_id intel_pstate_cpu_oob_ids[] __initconst = {
1417 	ICPU(INTEL_FAM6_BROADWELL_XEON_D, core_params),
1418 	ICPU(INTEL_FAM6_BROADWELL_X, core_params),
1419 	ICPU(INTEL_FAM6_SKYLAKE_X, core_params),
1420 	{}
1421 };
1422 
1423 static int intel_pstate_init_cpu(unsigned int cpunum)
1424 {
1425 	struct cpudata *cpu;
1426 
1427 	if (!all_cpu_data[cpunum])
1428 		all_cpu_data[cpunum] = kzalloc(sizeof(struct cpudata),
1429 					       GFP_KERNEL);
1430 	if (!all_cpu_data[cpunum])
1431 		return -ENOMEM;
1432 
1433 	cpu = all_cpu_data[cpunum];
1434 
1435 	cpu->cpu = cpunum;
1436 
1437 	if (hwp_active) {
1438 		intel_pstate_hwp_enable(cpu);
1439 		pid_params.sample_rate_ms = 50;
1440 		pid_params.sample_rate_ns = 50 * NSEC_PER_MSEC;
1441 	}
1442 
1443 	intel_pstate_get_cpu_pstates(cpu);
1444 
1445 	intel_pstate_busy_pid_reset(cpu);
1446 
1447 	pr_debug("controlling: cpu %d\n", cpunum);
1448 
1449 	return 0;
1450 }
1451 
1452 static unsigned int intel_pstate_get(unsigned int cpu_num)
1453 {
1454 	struct cpudata *cpu = all_cpu_data[cpu_num];
1455 
1456 	return cpu ? get_avg_frequency(cpu) : 0;
1457 }
1458 
1459 static void intel_pstate_set_update_util_hook(unsigned int cpu_num)
1460 {
1461 	struct cpudata *cpu = all_cpu_data[cpu_num];
1462 
1463 	if (cpu->update_util_set)
1464 		return;
1465 
1466 	/* Prevent intel_pstate_update_util() from using stale data. */
1467 	cpu->sample.time = 0;
1468 	cpufreq_add_update_util_hook(cpu_num, &cpu->update_util,
1469 				     intel_pstate_update_util);
1470 	cpu->update_util_set = true;
1471 }
1472 
1473 static void intel_pstate_clear_update_util_hook(unsigned int cpu)
1474 {
1475 	struct cpudata *cpu_data = all_cpu_data[cpu];
1476 
1477 	if (!cpu_data->update_util_set)
1478 		return;
1479 
1480 	cpufreq_remove_update_util_hook(cpu);
1481 	cpu_data->update_util_set = false;
1482 	synchronize_sched();
1483 }
1484 
1485 static void intel_pstate_set_performance_limits(struct perf_limits *limits)
1486 {
1487 	limits->no_turbo = 0;
1488 	limits->turbo_disabled = 0;
1489 	limits->max_perf_pct = 100;
1490 	limits->max_perf = int_tofp(1);
1491 	limits->min_perf_pct = 100;
1492 	limits->min_perf = int_tofp(1);
1493 	limits->max_policy_pct = 100;
1494 	limits->max_sysfs_pct = 100;
1495 	limits->min_policy_pct = 0;
1496 	limits->min_sysfs_pct = 0;
1497 }
1498 
1499 static int intel_pstate_set_policy(struct cpufreq_policy *policy)
1500 {
1501 	struct cpudata *cpu;
1502 
1503 	if (!policy->cpuinfo.max_freq)
1504 		return -ENODEV;
1505 
1506 	pr_debug("set_policy cpuinfo.max %u policy->max %u\n",
1507 		 policy->cpuinfo.max_freq, policy->max);
1508 
1509 	cpu = all_cpu_data[policy->cpu];
1510 	cpu->policy = policy->policy;
1511 
1512 	if (cpu->pstate.max_pstate_physical > cpu->pstate.max_pstate &&
1513 	    policy->max < policy->cpuinfo.max_freq &&
1514 	    policy->max > cpu->pstate.max_pstate * cpu->pstate.scaling) {
1515 		pr_debug("policy->max > max non turbo frequency\n");
1516 		policy->max = policy->cpuinfo.max_freq;
1517 	}
1518 
1519 	if (cpu->policy == CPUFREQ_POLICY_PERFORMANCE) {
1520 		limits = &performance_limits;
1521 		if (policy->max >= policy->cpuinfo.max_freq) {
1522 			pr_debug("set performance\n");
1523 			intel_pstate_set_performance_limits(limits);
1524 			goto out;
1525 		}
1526 	} else {
1527 		pr_debug("set powersave\n");
1528 		limits = &powersave_limits;
1529 	}
1530 
1531 	limits->min_policy_pct = (policy->min * 100) / policy->cpuinfo.max_freq;
1532 	limits->min_policy_pct = clamp_t(int, limits->min_policy_pct, 0 , 100);
1533 	limits->max_policy_pct = DIV_ROUND_UP(policy->max * 100,
1534 					      policy->cpuinfo.max_freq);
1535 	limits->max_policy_pct = clamp_t(int, limits->max_policy_pct, 0 , 100);
1536 
1537 	/* Normalize user input to [min_policy_pct, max_policy_pct] */
1538 	limits->min_perf_pct = max(limits->min_policy_pct,
1539 				   limits->min_sysfs_pct);
1540 	limits->min_perf_pct = min(limits->max_policy_pct,
1541 				   limits->min_perf_pct);
1542 	limits->max_perf_pct = min(limits->max_policy_pct,
1543 				   limits->max_sysfs_pct);
1544 	limits->max_perf_pct = max(limits->min_policy_pct,
1545 				   limits->max_perf_pct);
1546 
1547 	/* Make sure min_perf_pct <= max_perf_pct */
1548 	limits->min_perf_pct = min(limits->max_perf_pct, limits->min_perf_pct);
1549 
1550 	limits->min_perf = div_fp(limits->min_perf_pct, 100);
1551 	limits->max_perf = div_fp(limits->max_perf_pct, 100);
1552 	limits->max_perf = round_up(limits->max_perf, FRAC_BITS);
1553 
1554  out:
1555 	if (cpu->policy == CPUFREQ_POLICY_PERFORMANCE) {
1556 		/*
1557 		 * NOHZ_FULL CPUs need this as the governor callback may not
1558 		 * be invoked on them.
1559 		 */
1560 		intel_pstate_clear_update_util_hook(policy->cpu);
1561 		intel_pstate_max_within_limits(cpu);
1562 	}
1563 
1564 	intel_pstate_set_update_util_hook(policy->cpu);
1565 
1566 	intel_pstate_hwp_set_policy(policy);
1567 
1568 	return 0;
1569 }
1570 
1571 static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
1572 {
1573 	cpufreq_verify_within_cpu_limits(policy);
1574 
1575 	if (policy->policy != CPUFREQ_POLICY_POWERSAVE &&
1576 	    policy->policy != CPUFREQ_POLICY_PERFORMANCE)
1577 		return -EINVAL;
1578 
1579 	return 0;
1580 }
1581 
1582 static void intel_pstate_stop_cpu(struct cpufreq_policy *policy)
1583 {
1584 	int cpu_num = policy->cpu;
1585 	struct cpudata *cpu = all_cpu_data[cpu_num];
1586 
1587 	pr_debug("CPU %d exiting\n", cpu_num);
1588 
1589 	intel_pstate_clear_update_util_hook(cpu_num);
1590 
1591 	if (hwp_active)
1592 		return;
1593 
1594 	intel_pstate_set_min_pstate(cpu);
1595 }
1596 
1597 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
1598 {
1599 	struct cpudata *cpu;
1600 	int rc;
1601 
1602 	rc = intel_pstate_init_cpu(policy->cpu);
1603 	if (rc)
1604 		return rc;
1605 
1606 	cpu = all_cpu_data[policy->cpu];
1607 
1608 	if (limits->min_perf_pct == 100 && limits->max_perf_pct == 100)
1609 		policy->policy = CPUFREQ_POLICY_PERFORMANCE;
1610 	else
1611 		policy->policy = CPUFREQ_POLICY_POWERSAVE;
1612 
1613 	policy->min = cpu->pstate.min_pstate * cpu->pstate.scaling;
1614 	policy->max = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
1615 
1616 	/* cpuinfo and default policy values */
1617 	policy->cpuinfo.min_freq = cpu->pstate.min_pstate * cpu->pstate.scaling;
1618 	update_turbo_state();
1619 	policy->cpuinfo.max_freq = limits->turbo_disabled ?
1620 			cpu->pstate.max_pstate : cpu->pstate.turbo_pstate;
1621 	policy->cpuinfo.max_freq *= cpu->pstate.scaling;
1622 
1623 	intel_pstate_init_acpi_perf_limits(policy);
1624 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
1625 	cpumask_set_cpu(policy->cpu, policy->cpus);
1626 
1627 	return 0;
1628 }
1629 
1630 static int intel_pstate_cpu_exit(struct cpufreq_policy *policy)
1631 {
1632 	intel_pstate_exit_perf_limits(policy);
1633 
1634 	return 0;
1635 }
1636 
1637 static struct cpufreq_driver intel_pstate_driver = {
1638 	.flags		= CPUFREQ_CONST_LOOPS,
1639 	.verify		= intel_pstate_verify_policy,
1640 	.setpolicy	= intel_pstate_set_policy,
1641 	.resume		= intel_pstate_hwp_set_policy,
1642 	.get		= intel_pstate_get,
1643 	.init		= intel_pstate_cpu_init,
1644 	.exit		= intel_pstate_cpu_exit,
1645 	.stop_cpu	= intel_pstate_stop_cpu,
1646 	.name		= "intel_pstate",
1647 };
1648 
1649 static int no_load __initdata;
1650 static int no_hwp __initdata;
1651 static int hwp_only __initdata;
1652 static unsigned int force_load __initdata;
1653 
1654 static int __init intel_pstate_msrs_not_valid(void)
1655 {
1656 	if (!pstate_funcs.get_max() ||
1657 	    !pstate_funcs.get_min() ||
1658 	    !pstate_funcs.get_turbo())
1659 		return -ENODEV;
1660 
1661 	return 0;
1662 }
1663 
1664 static void __init copy_pid_params(struct pstate_adjust_policy *policy)
1665 {
1666 	pid_params.sample_rate_ms = policy->sample_rate_ms;
1667 	pid_params.sample_rate_ns = pid_params.sample_rate_ms * NSEC_PER_MSEC;
1668 	pid_params.p_gain_pct = policy->p_gain_pct;
1669 	pid_params.i_gain_pct = policy->i_gain_pct;
1670 	pid_params.d_gain_pct = policy->d_gain_pct;
1671 	pid_params.deadband = policy->deadband;
1672 	pid_params.setpoint = policy->setpoint;
1673 }
1674 
1675 static void __init copy_cpu_funcs(struct pstate_funcs *funcs)
1676 {
1677 	pstate_funcs.get_max   = funcs->get_max;
1678 	pstate_funcs.get_max_physical = funcs->get_max_physical;
1679 	pstate_funcs.get_min   = funcs->get_min;
1680 	pstate_funcs.get_turbo = funcs->get_turbo;
1681 	pstate_funcs.get_scaling = funcs->get_scaling;
1682 	pstate_funcs.get_val   = funcs->get_val;
1683 	pstate_funcs.get_vid   = funcs->get_vid;
1684 	pstate_funcs.get_target_pstate = funcs->get_target_pstate;
1685 
1686 }
1687 
1688 #ifdef CONFIG_ACPI
1689 
1690 static bool __init intel_pstate_no_acpi_pss(void)
1691 {
1692 	int i;
1693 
1694 	for_each_possible_cpu(i) {
1695 		acpi_status status;
1696 		union acpi_object *pss;
1697 		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1698 		struct acpi_processor *pr = per_cpu(processors, i);
1699 
1700 		if (!pr)
1701 			continue;
1702 
1703 		status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
1704 		if (ACPI_FAILURE(status))
1705 			continue;
1706 
1707 		pss = buffer.pointer;
1708 		if (pss && pss->type == ACPI_TYPE_PACKAGE) {
1709 			kfree(pss);
1710 			return false;
1711 		}
1712 
1713 		kfree(pss);
1714 	}
1715 
1716 	return true;
1717 }
1718 
1719 static bool __init intel_pstate_has_acpi_ppc(void)
1720 {
1721 	int i;
1722 
1723 	for_each_possible_cpu(i) {
1724 		struct acpi_processor *pr = per_cpu(processors, i);
1725 
1726 		if (!pr)
1727 			continue;
1728 		if (acpi_has_method(pr->handle, "_PPC"))
1729 			return true;
1730 	}
1731 	return false;
1732 }
1733 
1734 enum {
1735 	PSS,
1736 	PPC,
1737 };
1738 
1739 struct hw_vendor_info {
1740 	u16  valid;
1741 	char oem_id[ACPI_OEM_ID_SIZE];
1742 	char oem_table_id[ACPI_OEM_TABLE_ID_SIZE];
1743 	int  oem_pwr_table;
1744 };
1745 
1746 /* Hardware vendor-specific info that has its own power management modes */
1747 static struct hw_vendor_info vendor_info[] __initdata = {
1748 	{1, "HP    ", "ProLiant", PSS},
1749 	{1, "ORACLE", "X4-2    ", PPC},
1750 	{1, "ORACLE", "X4-2L   ", PPC},
1751 	{1, "ORACLE", "X4-2B   ", PPC},
1752 	{1, "ORACLE", "X3-2    ", PPC},
1753 	{1, "ORACLE", "X3-2L   ", PPC},
1754 	{1, "ORACLE", "X3-2B   ", PPC},
1755 	{1, "ORACLE", "X4470M2 ", PPC},
1756 	{1, "ORACLE", "X4270M3 ", PPC},
1757 	{1, "ORACLE", "X4270M2 ", PPC},
1758 	{1, "ORACLE", "X4170M2 ", PPC},
1759 	{1, "ORACLE", "X4170 M3", PPC},
1760 	{1, "ORACLE", "X4275 M3", PPC},
1761 	{1, "ORACLE", "X6-2    ", PPC},
1762 	{1, "ORACLE", "Sudbury ", PPC},
1763 	{0, "", ""},
1764 };
1765 
1766 static bool __init intel_pstate_platform_pwr_mgmt_exists(void)
1767 {
1768 	struct acpi_table_header hdr;
1769 	struct hw_vendor_info *v_info;
1770 	const struct x86_cpu_id *id;
1771 	u64 misc_pwr;
1772 
1773 	id = x86_match_cpu(intel_pstate_cpu_oob_ids);
1774 	if (id) {
1775 		rdmsrl(MSR_MISC_PWR_MGMT, misc_pwr);
1776 		if ( misc_pwr & (1 << 8))
1777 			return true;
1778 	}
1779 
1780 	if (acpi_disabled ||
1781 	    ACPI_FAILURE(acpi_get_table_header(ACPI_SIG_FADT, 0, &hdr)))
1782 		return false;
1783 
1784 	for (v_info = vendor_info; v_info->valid; v_info++) {
1785 		if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) &&
1786 			!strncmp(hdr.oem_table_id, v_info->oem_table_id,
1787 						ACPI_OEM_TABLE_ID_SIZE))
1788 			switch (v_info->oem_pwr_table) {
1789 			case PSS:
1790 				return intel_pstate_no_acpi_pss();
1791 			case PPC:
1792 				return intel_pstate_has_acpi_ppc() &&
1793 					(!force_load);
1794 			}
1795 	}
1796 
1797 	return false;
1798 }
1799 #else /* CONFIG_ACPI not enabled */
1800 static inline bool intel_pstate_platform_pwr_mgmt_exists(void) { return false; }
1801 static inline bool intel_pstate_has_acpi_ppc(void) { return false; }
1802 #endif /* CONFIG_ACPI */
1803 
1804 static const struct x86_cpu_id hwp_support_ids[] __initconst = {
1805 	{ X86_VENDOR_INTEL, 6, X86_MODEL_ANY, X86_FEATURE_HWP },
1806 	{}
1807 };
1808 
1809 static int __init intel_pstate_init(void)
1810 {
1811 	int cpu, rc = 0;
1812 	const struct x86_cpu_id *id;
1813 	struct cpu_defaults *cpu_def;
1814 
1815 	if (no_load)
1816 		return -ENODEV;
1817 
1818 	if (x86_match_cpu(hwp_support_ids) && !no_hwp) {
1819 		copy_cpu_funcs(&core_params.funcs);
1820 		hwp_active++;
1821 		goto hwp_cpu_matched;
1822 	}
1823 
1824 	id = x86_match_cpu(intel_pstate_cpu_ids);
1825 	if (!id)
1826 		return -ENODEV;
1827 
1828 	cpu_def = (struct cpu_defaults *)id->driver_data;
1829 
1830 	copy_pid_params(&cpu_def->pid_policy);
1831 	copy_cpu_funcs(&cpu_def->funcs);
1832 
1833 	if (intel_pstate_msrs_not_valid())
1834 		return -ENODEV;
1835 
1836 hwp_cpu_matched:
1837 	/*
1838 	 * The Intel pstate driver will be ignored if the platform
1839 	 * firmware has its own power management modes.
1840 	 */
1841 	if (intel_pstate_platform_pwr_mgmt_exists())
1842 		return -ENODEV;
1843 
1844 	pr_info("Intel P-state driver initializing\n");
1845 
1846 	all_cpu_data = vzalloc(sizeof(void *) * num_possible_cpus());
1847 	if (!all_cpu_data)
1848 		return -ENOMEM;
1849 
1850 	if (!hwp_active && hwp_only)
1851 		goto out;
1852 
1853 	rc = cpufreq_register_driver(&intel_pstate_driver);
1854 	if (rc)
1855 		goto out;
1856 
1857 	intel_pstate_debug_expose_params();
1858 	intel_pstate_sysfs_expose_params();
1859 
1860 	if (hwp_active)
1861 		pr_info("HWP enabled\n");
1862 
1863 	return rc;
1864 out:
1865 	get_online_cpus();
1866 	for_each_online_cpu(cpu) {
1867 		if (all_cpu_data[cpu]) {
1868 			intel_pstate_clear_update_util_hook(cpu);
1869 			kfree(all_cpu_data[cpu]);
1870 		}
1871 	}
1872 
1873 	put_online_cpus();
1874 	vfree(all_cpu_data);
1875 	return -ENODEV;
1876 }
1877 device_initcall(intel_pstate_init);
1878 
1879 static int __init intel_pstate_setup(char *str)
1880 {
1881 	if (!str)
1882 		return -EINVAL;
1883 
1884 	if (!strcmp(str, "disable"))
1885 		no_load = 1;
1886 	if (!strcmp(str, "no_hwp")) {
1887 		pr_info("HWP disabled\n");
1888 		no_hwp = 1;
1889 	}
1890 	if (!strcmp(str, "force"))
1891 		force_load = 1;
1892 	if (!strcmp(str, "hwp_only"))
1893 		hwp_only = 1;
1894 
1895 #ifdef CONFIG_ACPI
1896 	if (!strcmp(str, "support_acpi_ppc"))
1897 		acpi_ppc = true;
1898 #endif
1899 
1900 	return 0;
1901 }
1902 early_param("intel_pstate", intel_pstate_setup);
1903 
1904 MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>");
1905 MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors");
1906 MODULE_LICENSE("GPL");
1907