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 
39 #define ATOM_RATIOS		0x66a
40 #define ATOM_VIDS		0x66b
41 #define ATOM_TURBO_RATIOS	0x66c
42 #define ATOM_TURBO_VIDS		0x66d
43 
44 #ifdef CONFIG_ACPI
45 #include <acpi/processor.h>
46 #endif
47 
48 #define FRAC_BITS 8
49 #define int_tofp(X) ((int64_t)(X) << FRAC_BITS)
50 #define fp_toint(X) ((X) >> FRAC_BITS)
51 
52 static inline int32_t mul_fp(int32_t x, int32_t y)
53 {
54 	return ((int64_t)x * (int64_t)y) >> FRAC_BITS;
55 }
56 
57 static inline int32_t div_fp(s64 x, s64 y)
58 {
59 	return div64_s64((int64_t)x << FRAC_BITS, y);
60 }
61 
62 static inline int ceiling_fp(int32_t x)
63 {
64 	int mask, ret;
65 
66 	ret = fp_toint(x);
67 	mask = (1 << FRAC_BITS) - 1;
68 	if (x & mask)
69 		ret += 1;
70 	return ret;
71 }
72 
73 /**
74  * struct sample -	Store performance sample
75  * @core_pct_busy:	Ratio of APERF/MPERF in percent, which is actual
76  *			performance during last sample period
77  * @busy_scaled:	Scaled busy value which is used to calculate next
78  *			P state. This can be different than core_pct_busy
79  *			to account for cpu idle period
80  * @aperf:		Difference of actual performance frequency clock count
81  *			read from APERF MSR between last and current sample
82  * @mperf:		Difference of maximum performance frequency clock count
83  *			read from MPERF MSR between last and current sample
84  * @tsc:		Difference of time stamp counter between last and
85  *			current sample
86  * @freq:		Effective frequency calculated from APERF/MPERF
87  * @time:		Current time from scheduler
88  *
89  * This structure is used in the cpudata structure to store performance sample
90  * data for choosing next P State.
91  */
92 struct sample {
93 	int32_t core_pct_busy;
94 	int32_t busy_scaled;
95 	u64 aperf;
96 	u64 mperf;
97 	u64 tsc;
98 	int freq;
99 	u64 time;
100 };
101 
102 /**
103  * struct pstate_data - Store P state data
104  * @current_pstate:	Current requested P state
105  * @min_pstate:		Min P state possible for this platform
106  * @max_pstate:		Max P state possible for this platform
107  * @max_pstate_physical:This is physical Max P state for a processor
108  *			This can be higher than the max_pstate which can
109  *			be limited by platform thermal design power limits
110  * @scaling:		Scaling factor to  convert frequency to cpufreq
111  *			frequency units
112  * @turbo_pstate:	Max Turbo P state possible for this platform
113  *
114  * Stores the per cpu model P state limits and current P state.
115  */
116 struct pstate_data {
117 	int	current_pstate;
118 	int	min_pstate;
119 	int	max_pstate;
120 	int	max_pstate_physical;
121 	int	scaling;
122 	int	turbo_pstate;
123 };
124 
125 /**
126  * struct vid_data -	Stores voltage information data
127  * @min:		VID data for this platform corresponding to
128  *			the lowest P state
129  * @max:		VID data corresponding to the highest P State.
130  * @turbo:		VID data for turbo P state
131  * @ratio:		Ratio of (vid max - vid min) /
132  *			(max P state - Min P State)
133  *
134  * Stores the voltage data for DVFS (Dynamic Voltage and Frequency Scaling)
135  * This data is used in Atom platforms, where in addition to target P state,
136  * the voltage data needs to be specified to select next P State.
137  */
138 struct vid_data {
139 	int min;
140 	int max;
141 	int turbo;
142 	int32_t ratio;
143 };
144 
145 /**
146  * struct _pid -	Stores PID data
147  * @setpoint:		Target set point for busyness or performance
148  * @integral:		Storage for accumulated error values
149  * @p_gain:		PID proportional gain
150  * @i_gain:		PID integral gain
151  * @d_gain:		PID derivative gain
152  * @deadband:		PID deadband
153  * @last_err:		Last error storage for integral part of PID calculation
154  *
155  * Stores PID coefficients and last error for PID controller.
156  */
157 struct _pid {
158 	int setpoint;
159 	int32_t integral;
160 	int32_t p_gain;
161 	int32_t i_gain;
162 	int32_t d_gain;
163 	int deadband;
164 	int32_t last_err;
165 };
166 
167 /**
168  * struct cpudata -	Per CPU instance data storage
169  * @cpu:		CPU number for this instance data
170  * @update_util:	CPUFreq utility callback information
171  * @pstate:		Stores P state limits for this CPU
172  * @vid:		Stores VID limits for this CPU
173  * @pid:		Stores PID parameters for this CPU
174  * @last_sample_time:	Last Sample time
175  * @prev_aperf:		Last APERF value read from APERF MSR
176  * @prev_mperf:		Last MPERF value read from MPERF MSR
177  * @prev_tsc:		Last timestamp counter (TSC) value
178  * @prev_cummulative_iowait: IO Wait time difference from last and
179  *			current sample
180  * @sample:		Storage for storing last Sample data
181  * @acpi_perf_data:	Stores ACPI perf information read from _PSS
182  * @valid_pss_table:	Set to true for valid ACPI _PSS entries found
183  *
184  * This structure stores per CPU instance data for all CPUs.
185  */
186 struct cpudata {
187 	int cpu;
188 
189 	struct update_util_data update_util;
190 
191 	struct pstate_data pstate;
192 	struct vid_data vid;
193 	struct _pid pid;
194 
195 	u64	last_sample_time;
196 	u64	prev_aperf;
197 	u64	prev_mperf;
198 	u64	prev_tsc;
199 	u64	prev_cummulative_iowait;
200 	struct sample sample;
201 #ifdef CONFIG_ACPI
202 	struct acpi_processor_performance acpi_perf_data;
203 	bool valid_pss_table;
204 #endif
205 };
206 
207 static struct cpudata **all_cpu_data;
208 
209 /**
210  * struct pid_adjust_policy - Stores static PID configuration data
211  * @sample_rate_ms:	PID calculation sample rate in ms
212  * @sample_rate_ns:	Sample rate calculation in ns
213  * @deadband:		PID deadband
214  * @setpoint:		PID Setpoint
215  * @p_gain_pct:		PID proportional gain
216  * @i_gain_pct:		PID integral gain
217  * @d_gain_pct:		PID derivative gain
218  *
219  * Stores per CPU model static PID configuration data.
220  */
221 struct pstate_adjust_policy {
222 	int sample_rate_ms;
223 	s64 sample_rate_ns;
224 	int deadband;
225 	int setpoint;
226 	int p_gain_pct;
227 	int d_gain_pct;
228 	int i_gain_pct;
229 };
230 
231 /**
232  * struct pstate_funcs - Per CPU model specific callbacks
233  * @get_max:		Callback to get maximum non turbo effective P state
234  * @get_max_physical:	Callback to get maximum non turbo physical P state
235  * @get_min:		Callback to get minimum P state
236  * @get_turbo:		Callback to get turbo P state
237  * @get_scaling:	Callback to get frequency scaling factor
238  * @get_val:		Callback to convert P state to actual MSR write value
239  * @get_vid:		Callback to get VID data for Atom platforms
240  * @get_target_pstate:	Callback to a function to calculate next P state to use
241  *
242  * Core and Atom CPU models have different way to get P State limits. This
243  * structure is used to store those callbacks.
244  */
245 struct pstate_funcs {
246 	int (*get_max)(void);
247 	int (*get_max_physical)(void);
248 	int (*get_min)(void);
249 	int (*get_turbo)(void);
250 	int (*get_scaling)(void);
251 	u64 (*get_val)(struct cpudata*, int pstate);
252 	void (*get_vid)(struct cpudata *);
253 	int32_t (*get_target_pstate)(struct cpudata *);
254 };
255 
256 /**
257  * struct cpu_defaults- Per CPU model default config data
258  * @pid_policy:	PID config data
259  * @funcs:		Callback function data
260  */
261 struct cpu_defaults {
262 	struct pstate_adjust_policy pid_policy;
263 	struct pstate_funcs funcs;
264 };
265 
266 static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu);
267 static inline int32_t get_target_pstate_use_cpu_load(struct cpudata *cpu);
268 
269 static struct pstate_adjust_policy pid_params;
270 static struct pstate_funcs pstate_funcs;
271 static int hwp_active;
272 
273 #ifdef CONFIG_ACPI
274 static bool acpi_ppc;
275 #endif
276 
277 /**
278  * struct perf_limits - Store user and policy limits
279  * @no_turbo:		User requested turbo state from intel_pstate sysfs
280  * @turbo_disabled:	Platform turbo status either from msr
281  *			MSR_IA32_MISC_ENABLE or when maximum available pstate
282  *			matches the maximum turbo pstate
283  * @max_perf_pct:	Effective maximum performance limit in percentage, this
284  *			is minimum of either limits enforced by cpufreq policy
285  *			or limits from user set limits via intel_pstate sysfs
286  * @min_perf_pct:	Effective minimum performance limit in percentage, this
287  *			is maximum of either limits enforced by cpufreq policy
288  *			or limits from user set limits via intel_pstate sysfs
289  * @max_perf:		This is a scaled value between 0 to 255 for max_perf_pct
290  *			This value is used to limit max pstate
291  * @min_perf:		This is a scaled value between 0 to 255 for min_perf_pct
292  *			This value is used to limit min pstate
293  * @max_policy_pct:	The maximum performance in percentage enforced by
294  *			cpufreq setpolicy interface
295  * @max_sysfs_pct:	The maximum performance in percentage enforced by
296  *			intel pstate sysfs interface
297  * @min_policy_pct:	The minimum performance in percentage enforced by
298  *			cpufreq setpolicy interface
299  * @min_sysfs_pct:	The minimum performance in percentage enforced by
300  *			intel pstate sysfs interface
301  *
302  * Storage for user and policy defined limits.
303  */
304 struct perf_limits {
305 	int no_turbo;
306 	int turbo_disabled;
307 	int max_perf_pct;
308 	int min_perf_pct;
309 	int32_t max_perf;
310 	int32_t min_perf;
311 	int max_policy_pct;
312 	int max_sysfs_pct;
313 	int min_policy_pct;
314 	int min_sysfs_pct;
315 };
316 
317 static struct perf_limits performance_limits = {
318 	.no_turbo = 0,
319 	.turbo_disabled = 0,
320 	.max_perf_pct = 100,
321 	.max_perf = int_tofp(1),
322 	.min_perf_pct = 100,
323 	.min_perf = int_tofp(1),
324 	.max_policy_pct = 100,
325 	.max_sysfs_pct = 100,
326 	.min_policy_pct = 0,
327 	.min_sysfs_pct = 0,
328 };
329 
330 static struct perf_limits powersave_limits = {
331 	.no_turbo = 0,
332 	.turbo_disabled = 0,
333 	.max_perf_pct = 100,
334 	.max_perf = int_tofp(1),
335 	.min_perf_pct = 0,
336 	.min_perf = 0,
337 	.max_policy_pct = 100,
338 	.max_sysfs_pct = 100,
339 	.min_policy_pct = 0,
340 	.min_sysfs_pct = 0,
341 };
342 
343 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
344 static struct perf_limits *limits = &performance_limits;
345 #else
346 static struct perf_limits *limits = &powersave_limits;
347 #endif
348 
349 #ifdef CONFIG_ACPI
350 
351 static bool intel_pstate_get_ppc_enable_status(void)
352 {
353 	if (acpi_gbl_FADT.preferred_profile == PM_ENTERPRISE_SERVER ||
354 	    acpi_gbl_FADT.preferred_profile == PM_PERFORMANCE_SERVER)
355 		return true;
356 
357 	return acpi_ppc;
358 }
359 
360 /*
361  * The max target pstate ratio is a 8 bit value in both PLATFORM_INFO MSR and
362  * in TURBO_RATIO_LIMIT MSR, which pstate driver stores in max_pstate and
363  * max_turbo_pstate fields. The PERF_CTL MSR contains 16 bit value for P state
364  * ratio, out of it only high 8 bits are used. For example 0x1700 is setting
365  * target ratio 0x17. The _PSS control value stores in a format which can be
366  * directly written to PERF_CTL MSR. But in intel_pstate driver this shift
367  * occurs during write to PERF_CTL (E.g. for cores core_set_pstate()).
368  * This function converts the _PSS control value to intel pstate driver format
369  * for comparison and assignment.
370  */
371 static int convert_to_native_pstate_format(struct cpudata *cpu, int index)
372 {
373 	return cpu->acpi_perf_data.states[index].control >> 8;
374 }
375 
376 static void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy)
377 {
378 	struct cpudata *cpu;
379 	int turbo_pss_ctl;
380 	int ret;
381 	int i;
382 
383 	if (hwp_active)
384 		return;
385 
386 	if (!intel_pstate_get_ppc_enable_status())
387 		return;
388 
389 	cpu = all_cpu_data[policy->cpu];
390 
391 	ret = acpi_processor_register_performance(&cpu->acpi_perf_data,
392 						  policy->cpu);
393 	if (ret)
394 		return;
395 
396 	/*
397 	 * Check if the control value in _PSS is for PERF_CTL MSR, which should
398 	 * guarantee that the states returned by it map to the states in our
399 	 * list directly.
400 	 */
401 	if (cpu->acpi_perf_data.control_register.space_id !=
402 						ACPI_ADR_SPACE_FIXED_HARDWARE)
403 		goto err;
404 
405 	/*
406 	 * If there is only one entry _PSS, simply ignore _PSS and continue as
407 	 * usual without taking _PSS into account
408 	 */
409 	if (cpu->acpi_perf_data.state_count < 2)
410 		goto err;
411 
412 	pr_debug("CPU%u - ACPI _PSS perf data\n", policy->cpu);
413 	for (i = 0; i < cpu->acpi_perf_data.state_count; i++) {
414 		pr_debug("     %cP%d: %u MHz, %u mW, 0x%x\n",
415 			 (i == cpu->acpi_perf_data.state ? '*' : ' '), i,
416 			 (u32) cpu->acpi_perf_data.states[i].core_frequency,
417 			 (u32) cpu->acpi_perf_data.states[i].power,
418 			 (u32) cpu->acpi_perf_data.states[i].control);
419 	}
420 
421 	/*
422 	 * The _PSS table doesn't contain whole turbo frequency range.
423 	 * This just contains +1 MHZ above the max non turbo frequency,
424 	 * with control value corresponding to max turbo ratio. But
425 	 * when cpufreq set policy is called, it will call with this
426 	 * max frequency, which will cause a reduced performance as
427 	 * this driver uses real max turbo frequency as the max
428 	 * frequency. So correct this frequency in _PSS table to
429 	 * correct max turbo frequency based on the turbo ratio.
430 	 * Also need to convert to MHz as _PSS freq is in MHz.
431 	 */
432 	turbo_pss_ctl = convert_to_native_pstate_format(cpu, 0);
433 	if (turbo_pss_ctl > cpu->pstate.max_pstate)
434 		cpu->acpi_perf_data.states[0].core_frequency =
435 					policy->cpuinfo.max_freq / 1000;
436 	cpu->valid_pss_table = true;
437 	pr_info("_PPC limits will be enforced\n");
438 
439 	return;
440 
441  err:
442 	cpu->valid_pss_table = false;
443 	acpi_processor_unregister_performance(policy->cpu);
444 }
445 
446 static void intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
447 {
448 	struct cpudata *cpu;
449 
450 	cpu = all_cpu_data[policy->cpu];
451 	if (!cpu->valid_pss_table)
452 		return;
453 
454 	acpi_processor_unregister_performance(policy->cpu);
455 }
456 
457 #else
458 static void intel_pstate_init_acpi_perf_limits(struct cpufreq_policy *policy)
459 {
460 }
461 
462 static void intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
463 {
464 }
465 #endif
466 
467 static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
468 			     int deadband, int integral) {
469 	pid->setpoint = int_tofp(setpoint);
470 	pid->deadband  = int_tofp(deadband);
471 	pid->integral  = int_tofp(integral);
472 	pid->last_err  = int_tofp(setpoint) - int_tofp(busy);
473 }
474 
475 static inline void pid_p_gain_set(struct _pid *pid, int percent)
476 {
477 	pid->p_gain = div_fp(percent, 100);
478 }
479 
480 static inline void pid_i_gain_set(struct _pid *pid, int percent)
481 {
482 	pid->i_gain = div_fp(percent, 100);
483 }
484 
485 static inline void pid_d_gain_set(struct _pid *pid, int percent)
486 {
487 	pid->d_gain = div_fp(percent, 100);
488 }
489 
490 static signed int pid_calc(struct _pid *pid, int32_t busy)
491 {
492 	signed int result;
493 	int32_t pterm, dterm, fp_error;
494 	int32_t integral_limit;
495 
496 	fp_error = pid->setpoint - busy;
497 
498 	if (abs(fp_error) <= pid->deadband)
499 		return 0;
500 
501 	pterm = mul_fp(pid->p_gain, fp_error);
502 
503 	pid->integral += fp_error;
504 
505 	/*
506 	 * We limit the integral here so that it will never
507 	 * get higher than 30.  This prevents it from becoming
508 	 * too large an input over long periods of time and allows
509 	 * it to get factored out sooner.
510 	 *
511 	 * The value of 30 was chosen through experimentation.
512 	 */
513 	integral_limit = int_tofp(30);
514 	if (pid->integral > integral_limit)
515 		pid->integral = integral_limit;
516 	if (pid->integral < -integral_limit)
517 		pid->integral = -integral_limit;
518 
519 	dterm = mul_fp(pid->d_gain, fp_error - pid->last_err);
520 	pid->last_err = fp_error;
521 
522 	result = pterm + mul_fp(pid->integral, pid->i_gain) + dterm;
523 	result = result + (1 << (FRAC_BITS-1));
524 	return (signed int)fp_toint(result);
525 }
526 
527 static inline void intel_pstate_busy_pid_reset(struct cpudata *cpu)
528 {
529 	pid_p_gain_set(&cpu->pid, pid_params.p_gain_pct);
530 	pid_d_gain_set(&cpu->pid, pid_params.d_gain_pct);
531 	pid_i_gain_set(&cpu->pid, pid_params.i_gain_pct);
532 
533 	pid_reset(&cpu->pid, pid_params.setpoint, 100, pid_params.deadband, 0);
534 }
535 
536 static inline void intel_pstate_reset_all_pid(void)
537 {
538 	unsigned int cpu;
539 
540 	for_each_online_cpu(cpu) {
541 		if (all_cpu_data[cpu])
542 			intel_pstate_busy_pid_reset(all_cpu_data[cpu]);
543 	}
544 }
545 
546 static inline void update_turbo_state(void)
547 {
548 	u64 misc_en;
549 	struct cpudata *cpu;
550 
551 	cpu = all_cpu_data[0];
552 	rdmsrl(MSR_IA32_MISC_ENABLE, misc_en);
553 	limits->turbo_disabled =
554 		(misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE ||
555 		 cpu->pstate.max_pstate == cpu->pstate.turbo_pstate);
556 }
557 
558 static void intel_pstate_hwp_set(const struct cpumask *cpumask)
559 {
560 	int min, hw_min, max, hw_max, cpu, range, adj_range;
561 	u64 value, cap;
562 
563 	rdmsrl(MSR_HWP_CAPABILITIES, cap);
564 	hw_min = HWP_LOWEST_PERF(cap);
565 	hw_max = HWP_HIGHEST_PERF(cap);
566 	range = hw_max - hw_min;
567 
568 	for_each_cpu(cpu, cpumask) {
569 		rdmsrl_on_cpu(cpu, MSR_HWP_REQUEST, &value);
570 		adj_range = limits->min_perf_pct * range / 100;
571 		min = hw_min + adj_range;
572 		value &= ~HWP_MIN_PERF(~0L);
573 		value |= HWP_MIN_PERF(min);
574 
575 		adj_range = limits->max_perf_pct * range / 100;
576 		max = hw_min + adj_range;
577 		if (limits->no_turbo) {
578 			hw_max = HWP_GUARANTEED_PERF(cap);
579 			if (hw_max < max)
580 				max = hw_max;
581 		}
582 
583 		value &= ~HWP_MAX_PERF(~0L);
584 		value |= HWP_MAX_PERF(max);
585 		wrmsrl_on_cpu(cpu, MSR_HWP_REQUEST, value);
586 	}
587 }
588 
589 static int intel_pstate_hwp_set_policy(struct cpufreq_policy *policy)
590 {
591 	if (hwp_active)
592 		intel_pstate_hwp_set(policy->cpus);
593 
594 	return 0;
595 }
596 
597 static void intel_pstate_hwp_set_online_cpus(void)
598 {
599 	get_online_cpus();
600 	intel_pstate_hwp_set(cpu_online_mask);
601 	put_online_cpus();
602 }
603 
604 /************************** debugfs begin ************************/
605 static int pid_param_set(void *data, u64 val)
606 {
607 	*(u32 *)data = val;
608 	intel_pstate_reset_all_pid();
609 	return 0;
610 }
611 
612 static int pid_param_get(void *data, u64 *val)
613 {
614 	*val = *(u32 *)data;
615 	return 0;
616 }
617 DEFINE_SIMPLE_ATTRIBUTE(fops_pid_param, pid_param_get, pid_param_set, "%llu\n");
618 
619 struct pid_param {
620 	char *name;
621 	void *value;
622 };
623 
624 static struct pid_param pid_files[] = {
625 	{"sample_rate_ms", &pid_params.sample_rate_ms},
626 	{"d_gain_pct", &pid_params.d_gain_pct},
627 	{"i_gain_pct", &pid_params.i_gain_pct},
628 	{"deadband", &pid_params.deadband},
629 	{"setpoint", &pid_params.setpoint},
630 	{"p_gain_pct", &pid_params.p_gain_pct},
631 	{NULL, NULL}
632 };
633 
634 static void __init intel_pstate_debug_expose_params(void)
635 {
636 	struct dentry *debugfs_parent;
637 	int i = 0;
638 
639 	if (hwp_active)
640 		return;
641 	debugfs_parent = debugfs_create_dir("pstate_snb", NULL);
642 	if (IS_ERR_OR_NULL(debugfs_parent))
643 		return;
644 	while (pid_files[i].name) {
645 		debugfs_create_file(pid_files[i].name, 0660,
646 				    debugfs_parent, pid_files[i].value,
647 				    &fops_pid_param);
648 		i++;
649 	}
650 }
651 
652 /************************** debugfs end ************************/
653 
654 /************************** sysfs begin ************************/
655 #define show_one(file_name, object)					\
656 	static ssize_t show_##file_name					\
657 	(struct kobject *kobj, struct attribute *attr, char *buf)	\
658 	{								\
659 		return sprintf(buf, "%u\n", limits->object);		\
660 	}
661 
662 static ssize_t show_turbo_pct(struct kobject *kobj,
663 				struct attribute *attr, char *buf)
664 {
665 	struct cpudata *cpu;
666 	int total, no_turbo, turbo_pct;
667 	uint32_t turbo_fp;
668 
669 	cpu = all_cpu_data[0];
670 
671 	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
672 	no_turbo = cpu->pstate.max_pstate - cpu->pstate.min_pstate + 1;
673 	turbo_fp = div_fp(no_turbo, total);
674 	turbo_pct = 100 - fp_toint(mul_fp(turbo_fp, int_tofp(100)));
675 	return sprintf(buf, "%u\n", turbo_pct);
676 }
677 
678 static ssize_t show_num_pstates(struct kobject *kobj,
679 				struct attribute *attr, char *buf)
680 {
681 	struct cpudata *cpu;
682 	int total;
683 
684 	cpu = all_cpu_data[0];
685 	total = cpu->pstate.turbo_pstate - cpu->pstate.min_pstate + 1;
686 	return sprintf(buf, "%u\n", total);
687 }
688 
689 static ssize_t show_no_turbo(struct kobject *kobj,
690 			     struct attribute *attr, char *buf)
691 {
692 	ssize_t ret;
693 
694 	update_turbo_state();
695 	if (limits->turbo_disabled)
696 		ret = sprintf(buf, "%u\n", limits->turbo_disabled);
697 	else
698 		ret = sprintf(buf, "%u\n", limits->no_turbo);
699 
700 	return ret;
701 }
702 
703 static ssize_t store_no_turbo(struct kobject *a, struct attribute *b,
704 			      const char *buf, size_t count)
705 {
706 	unsigned int input;
707 	int ret;
708 
709 	ret = sscanf(buf, "%u", &input);
710 	if (ret != 1)
711 		return -EINVAL;
712 
713 	update_turbo_state();
714 	if (limits->turbo_disabled) {
715 		pr_warn("Turbo disabled by BIOS or unavailable on processor\n");
716 		return -EPERM;
717 	}
718 
719 	limits->no_turbo = clamp_t(int, input, 0, 1);
720 
721 	if (hwp_active)
722 		intel_pstate_hwp_set_online_cpus();
723 
724 	return count;
725 }
726 
727 static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b,
728 				  const char *buf, size_t count)
729 {
730 	unsigned int input;
731 	int ret;
732 
733 	ret = sscanf(buf, "%u", &input);
734 	if (ret != 1)
735 		return -EINVAL;
736 
737 	limits->max_sysfs_pct = clamp_t(int, input, 0 , 100);
738 	limits->max_perf_pct = min(limits->max_policy_pct,
739 				   limits->max_sysfs_pct);
740 	limits->max_perf_pct = max(limits->min_policy_pct,
741 				   limits->max_perf_pct);
742 	limits->max_perf_pct = max(limits->min_perf_pct,
743 				   limits->max_perf_pct);
744 	limits->max_perf = div_fp(limits->max_perf_pct, 100);
745 
746 	if (hwp_active)
747 		intel_pstate_hwp_set_online_cpus();
748 	return count;
749 }
750 
751 static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b,
752 				  const char *buf, size_t count)
753 {
754 	unsigned int input;
755 	int ret;
756 
757 	ret = sscanf(buf, "%u", &input);
758 	if (ret != 1)
759 		return -EINVAL;
760 
761 	limits->min_sysfs_pct = clamp_t(int, input, 0 , 100);
762 	limits->min_perf_pct = max(limits->min_policy_pct,
763 				   limits->min_sysfs_pct);
764 	limits->min_perf_pct = min(limits->max_policy_pct,
765 				   limits->min_perf_pct);
766 	limits->min_perf_pct = min(limits->max_perf_pct,
767 				   limits->min_perf_pct);
768 	limits->min_perf = div_fp(limits->min_perf_pct, 100);
769 
770 	if (hwp_active)
771 		intel_pstate_hwp_set_online_cpus();
772 	return count;
773 }
774 
775 show_one(max_perf_pct, max_perf_pct);
776 show_one(min_perf_pct, min_perf_pct);
777 
778 define_one_global_rw(no_turbo);
779 define_one_global_rw(max_perf_pct);
780 define_one_global_rw(min_perf_pct);
781 define_one_global_ro(turbo_pct);
782 define_one_global_ro(num_pstates);
783 
784 static struct attribute *intel_pstate_attributes[] = {
785 	&no_turbo.attr,
786 	&max_perf_pct.attr,
787 	&min_perf_pct.attr,
788 	&turbo_pct.attr,
789 	&num_pstates.attr,
790 	NULL
791 };
792 
793 static struct attribute_group intel_pstate_attr_group = {
794 	.attrs = intel_pstate_attributes,
795 };
796 
797 static void __init intel_pstate_sysfs_expose_params(void)
798 {
799 	struct kobject *intel_pstate_kobject;
800 	int rc;
801 
802 	intel_pstate_kobject = kobject_create_and_add("intel_pstate",
803 						&cpu_subsys.dev_root->kobj);
804 	BUG_ON(!intel_pstate_kobject);
805 	rc = sysfs_create_group(intel_pstate_kobject, &intel_pstate_attr_group);
806 	BUG_ON(rc);
807 }
808 /************************** sysfs end ************************/
809 
810 static void intel_pstate_hwp_enable(struct cpudata *cpudata)
811 {
812 	/* First disable HWP notification interrupt as we don't process them */
813 	wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_INTERRUPT, 0x00);
814 
815 	wrmsrl_on_cpu(cpudata->cpu, MSR_PM_ENABLE, 0x1);
816 }
817 
818 static int atom_get_min_pstate(void)
819 {
820 	u64 value;
821 
822 	rdmsrl(ATOM_RATIOS, value);
823 	return (value >> 8) & 0x7F;
824 }
825 
826 static int atom_get_max_pstate(void)
827 {
828 	u64 value;
829 
830 	rdmsrl(ATOM_RATIOS, value);
831 	return (value >> 16) & 0x7F;
832 }
833 
834 static int atom_get_turbo_pstate(void)
835 {
836 	u64 value;
837 
838 	rdmsrl(ATOM_TURBO_RATIOS, value);
839 	return value & 0x7F;
840 }
841 
842 static u64 atom_get_val(struct cpudata *cpudata, int pstate)
843 {
844 	u64 val;
845 	int32_t vid_fp;
846 	u32 vid;
847 
848 	val = (u64)pstate << 8;
849 	if (limits->no_turbo && !limits->turbo_disabled)
850 		val |= (u64)1 << 32;
851 
852 	vid_fp = cpudata->vid.min + mul_fp(
853 		int_tofp(pstate - cpudata->pstate.min_pstate),
854 		cpudata->vid.ratio);
855 
856 	vid_fp = clamp_t(int32_t, vid_fp, cpudata->vid.min, cpudata->vid.max);
857 	vid = ceiling_fp(vid_fp);
858 
859 	if (pstate > cpudata->pstate.max_pstate)
860 		vid = cpudata->vid.turbo;
861 
862 	return val | vid;
863 }
864 
865 static int silvermont_get_scaling(void)
866 {
867 	u64 value;
868 	int i;
869 	/* Defined in Table 35-6 from SDM (Sept 2015) */
870 	static int silvermont_freq_table[] = {
871 		83300, 100000, 133300, 116700, 80000};
872 
873 	rdmsrl(MSR_FSB_FREQ, value);
874 	i = value & 0x7;
875 	WARN_ON(i > 4);
876 
877 	return silvermont_freq_table[i];
878 }
879 
880 static int airmont_get_scaling(void)
881 {
882 	u64 value;
883 	int i;
884 	/* Defined in Table 35-10 from SDM (Sept 2015) */
885 	static int airmont_freq_table[] = {
886 		83300, 100000, 133300, 116700, 80000,
887 		93300, 90000, 88900, 87500};
888 
889 	rdmsrl(MSR_FSB_FREQ, value);
890 	i = value & 0xF;
891 	WARN_ON(i > 8);
892 
893 	return airmont_freq_table[i];
894 }
895 
896 static void atom_get_vid(struct cpudata *cpudata)
897 {
898 	u64 value;
899 
900 	rdmsrl(ATOM_VIDS, value);
901 	cpudata->vid.min = int_tofp((value >> 8) & 0x7f);
902 	cpudata->vid.max = int_tofp((value >> 16) & 0x7f);
903 	cpudata->vid.ratio = div_fp(
904 		cpudata->vid.max - cpudata->vid.min,
905 		int_tofp(cpudata->pstate.max_pstate -
906 			cpudata->pstate.min_pstate));
907 
908 	rdmsrl(ATOM_TURBO_VIDS, value);
909 	cpudata->vid.turbo = value & 0x7f;
910 }
911 
912 static int core_get_min_pstate(void)
913 {
914 	u64 value;
915 
916 	rdmsrl(MSR_PLATFORM_INFO, value);
917 	return (value >> 40) & 0xFF;
918 }
919 
920 static int core_get_max_pstate_physical(void)
921 {
922 	u64 value;
923 
924 	rdmsrl(MSR_PLATFORM_INFO, value);
925 	return (value >> 8) & 0xFF;
926 }
927 
928 static int core_get_max_pstate(void)
929 {
930 	u64 tar;
931 	u64 plat_info;
932 	int max_pstate;
933 	int err;
934 
935 	rdmsrl(MSR_PLATFORM_INFO, plat_info);
936 	max_pstate = (plat_info >> 8) & 0xFF;
937 
938 	err = rdmsrl_safe(MSR_TURBO_ACTIVATION_RATIO, &tar);
939 	if (!err) {
940 		/* Do some sanity checking for safety */
941 		if (plat_info & 0x600000000) {
942 			u64 tdp_ctrl;
943 			u64 tdp_ratio;
944 			int tdp_msr;
945 
946 			err = rdmsrl_safe(MSR_CONFIG_TDP_CONTROL, &tdp_ctrl);
947 			if (err)
948 				goto skip_tar;
949 
950 			tdp_msr = MSR_CONFIG_TDP_NOMINAL + tdp_ctrl;
951 			err = rdmsrl_safe(tdp_msr, &tdp_ratio);
952 			if (err)
953 				goto skip_tar;
954 
955 			/* For level 1 and 2, bits[23:16] contain the ratio */
956 			if (tdp_ctrl)
957 				tdp_ratio >>= 16;
958 
959 			tdp_ratio &= 0xff; /* ratios are only 8 bits long */
960 			if (tdp_ratio - 1 == tar) {
961 				max_pstate = tar;
962 				pr_debug("max_pstate=TAC %x\n", max_pstate);
963 			} else {
964 				goto skip_tar;
965 			}
966 		}
967 	}
968 
969 skip_tar:
970 	return max_pstate;
971 }
972 
973 static int core_get_turbo_pstate(void)
974 {
975 	u64 value;
976 	int nont, ret;
977 
978 	rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value);
979 	nont = core_get_max_pstate();
980 	ret = (value) & 255;
981 	if (ret <= nont)
982 		ret = nont;
983 	return ret;
984 }
985 
986 static inline int core_get_scaling(void)
987 {
988 	return 100000;
989 }
990 
991 static u64 core_get_val(struct cpudata *cpudata, int pstate)
992 {
993 	u64 val;
994 
995 	val = (u64)pstate << 8;
996 	if (limits->no_turbo && !limits->turbo_disabled)
997 		val |= (u64)1 << 32;
998 
999 	return val;
1000 }
1001 
1002 static int knl_get_turbo_pstate(void)
1003 {
1004 	u64 value;
1005 	int nont, ret;
1006 
1007 	rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value);
1008 	nont = core_get_max_pstate();
1009 	ret = (((value) >> 8) & 0xFF);
1010 	if (ret <= nont)
1011 		ret = nont;
1012 	return ret;
1013 }
1014 
1015 static struct cpu_defaults core_params = {
1016 	.pid_policy = {
1017 		.sample_rate_ms = 10,
1018 		.deadband = 0,
1019 		.setpoint = 97,
1020 		.p_gain_pct = 20,
1021 		.d_gain_pct = 0,
1022 		.i_gain_pct = 0,
1023 	},
1024 	.funcs = {
1025 		.get_max = core_get_max_pstate,
1026 		.get_max_physical = core_get_max_pstate_physical,
1027 		.get_min = core_get_min_pstate,
1028 		.get_turbo = core_get_turbo_pstate,
1029 		.get_scaling = core_get_scaling,
1030 		.get_val = core_get_val,
1031 		.get_target_pstate = get_target_pstate_use_performance,
1032 	},
1033 };
1034 
1035 static struct cpu_defaults silvermont_params = {
1036 	.pid_policy = {
1037 		.sample_rate_ms = 10,
1038 		.deadband = 0,
1039 		.setpoint = 60,
1040 		.p_gain_pct = 14,
1041 		.d_gain_pct = 0,
1042 		.i_gain_pct = 4,
1043 	},
1044 	.funcs = {
1045 		.get_max = atom_get_max_pstate,
1046 		.get_max_physical = atom_get_max_pstate,
1047 		.get_min = atom_get_min_pstate,
1048 		.get_turbo = atom_get_turbo_pstate,
1049 		.get_val = atom_get_val,
1050 		.get_scaling = silvermont_get_scaling,
1051 		.get_vid = atom_get_vid,
1052 		.get_target_pstate = get_target_pstate_use_cpu_load,
1053 	},
1054 };
1055 
1056 static struct cpu_defaults airmont_params = {
1057 	.pid_policy = {
1058 		.sample_rate_ms = 10,
1059 		.deadband = 0,
1060 		.setpoint = 60,
1061 		.p_gain_pct = 14,
1062 		.d_gain_pct = 0,
1063 		.i_gain_pct = 4,
1064 	},
1065 	.funcs = {
1066 		.get_max = atom_get_max_pstate,
1067 		.get_max_physical = atom_get_max_pstate,
1068 		.get_min = atom_get_min_pstate,
1069 		.get_turbo = atom_get_turbo_pstate,
1070 		.get_val = atom_get_val,
1071 		.get_scaling = airmont_get_scaling,
1072 		.get_vid = atom_get_vid,
1073 		.get_target_pstate = get_target_pstate_use_cpu_load,
1074 	},
1075 };
1076 
1077 static struct cpu_defaults knl_params = {
1078 	.pid_policy = {
1079 		.sample_rate_ms = 10,
1080 		.deadband = 0,
1081 		.setpoint = 97,
1082 		.p_gain_pct = 20,
1083 		.d_gain_pct = 0,
1084 		.i_gain_pct = 0,
1085 	},
1086 	.funcs = {
1087 		.get_max = core_get_max_pstate,
1088 		.get_max_physical = core_get_max_pstate_physical,
1089 		.get_min = core_get_min_pstate,
1090 		.get_turbo = knl_get_turbo_pstate,
1091 		.get_scaling = core_get_scaling,
1092 		.get_val = core_get_val,
1093 		.get_target_pstate = get_target_pstate_use_performance,
1094 	},
1095 };
1096 
1097 static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max)
1098 {
1099 	int max_perf = cpu->pstate.turbo_pstate;
1100 	int max_perf_adj;
1101 	int min_perf;
1102 
1103 	if (limits->no_turbo || limits->turbo_disabled)
1104 		max_perf = cpu->pstate.max_pstate;
1105 
1106 	/*
1107 	 * performance can be limited by user through sysfs, by cpufreq
1108 	 * policy, or by cpu specific default values determined through
1109 	 * experimentation.
1110 	 */
1111 	max_perf_adj = fp_toint(max_perf * limits->max_perf);
1112 	*max = clamp_t(int, max_perf_adj,
1113 			cpu->pstate.min_pstate, cpu->pstate.turbo_pstate);
1114 
1115 	min_perf = fp_toint(max_perf * limits->min_perf);
1116 	*min = clamp_t(int, min_perf, cpu->pstate.min_pstate, max_perf);
1117 }
1118 
1119 static inline void intel_pstate_record_pstate(struct cpudata *cpu, int pstate)
1120 {
1121 	trace_cpu_frequency(pstate * cpu->pstate.scaling, cpu->cpu);
1122 	cpu->pstate.current_pstate = pstate;
1123 }
1124 
1125 static void intel_pstate_set_min_pstate(struct cpudata *cpu)
1126 {
1127 	int pstate = cpu->pstate.min_pstate;
1128 
1129 	intel_pstate_record_pstate(cpu, pstate);
1130 	/*
1131 	 * Generally, there is no guarantee that this code will always run on
1132 	 * the CPU being updated, so force the register update to run on the
1133 	 * right CPU.
1134 	 */
1135 	wrmsrl_on_cpu(cpu->cpu, MSR_IA32_PERF_CTL,
1136 		      pstate_funcs.get_val(cpu, pstate));
1137 }
1138 
1139 static void intel_pstate_get_cpu_pstates(struct cpudata *cpu)
1140 {
1141 	cpu->pstate.min_pstate = pstate_funcs.get_min();
1142 	cpu->pstate.max_pstate = pstate_funcs.get_max();
1143 	cpu->pstate.max_pstate_physical = pstate_funcs.get_max_physical();
1144 	cpu->pstate.turbo_pstate = pstate_funcs.get_turbo();
1145 	cpu->pstate.scaling = pstate_funcs.get_scaling();
1146 
1147 	if (pstate_funcs.get_vid)
1148 		pstate_funcs.get_vid(cpu);
1149 
1150 	intel_pstate_set_min_pstate(cpu);
1151 }
1152 
1153 static inline void intel_pstate_calc_busy(struct cpudata *cpu)
1154 {
1155 	struct sample *sample = &cpu->sample;
1156 	int64_t core_pct;
1157 
1158 	core_pct = sample->aperf * int_tofp(100);
1159 	core_pct = div64_u64(core_pct, sample->mperf);
1160 
1161 	sample->core_pct_busy = (int32_t)core_pct;
1162 }
1163 
1164 static inline bool intel_pstate_sample(struct cpudata *cpu, u64 time)
1165 {
1166 	u64 aperf, mperf;
1167 	unsigned long flags;
1168 	u64 tsc;
1169 
1170 	local_irq_save(flags);
1171 	rdmsrl(MSR_IA32_APERF, aperf);
1172 	rdmsrl(MSR_IA32_MPERF, mperf);
1173 	tsc = rdtsc();
1174 	if (cpu->prev_mperf == mperf || cpu->prev_tsc == tsc) {
1175 		local_irq_restore(flags);
1176 		return false;
1177 	}
1178 	local_irq_restore(flags);
1179 
1180 	cpu->last_sample_time = cpu->sample.time;
1181 	cpu->sample.time = time;
1182 	cpu->sample.aperf = aperf;
1183 	cpu->sample.mperf = mperf;
1184 	cpu->sample.tsc =  tsc;
1185 	cpu->sample.aperf -= cpu->prev_aperf;
1186 	cpu->sample.mperf -= cpu->prev_mperf;
1187 	cpu->sample.tsc -= cpu->prev_tsc;
1188 
1189 	cpu->prev_aperf = aperf;
1190 	cpu->prev_mperf = mperf;
1191 	cpu->prev_tsc = tsc;
1192 	/*
1193 	 * First time this function is invoked in a given cycle, all of the
1194 	 * previous sample data fields are equal to zero or stale and they must
1195 	 * be populated with meaningful numbers for things to work, so assume
1196 	 * that sample.time will always be reset before setting the utilization
1197 	 * update hook and make the caller skip the sample then.
1198 	 */
1199 	return !!cpu->last_sample_time;
1200 }
1201 
1202 static inline int32_t get_avg_frequency(struct cpudata *cpu)
1203 {
1204 	return fp_toint(mul_fp(cpu->sample.core_pct_busy,
1205 			       int_tofp(cpu->pstate.max_pstate_physical *
1206 						cpu->pstate.scaling / 100)));
1207 }
1208 
1209 static inline int32_t get_avg_pstate(struct cpudata *cpu)
1210 {
1211 	return div64_u64(cpu->pstate.max_pstate_physical * cpu->sample.aperf,
1212 			 cpu->sample.mperf);
1213 }
1214 
1215 static inline int32_t get_target_pstate_use_cpu_load(struct cpudata *cpu)
1216 {
1217 	struct sample *sample = &cpu->sample;
1218 	u64 cummulative_iowait, delta_iowait_us;
1219 	u64 delta_iowait_mperf;
1220 	u64 mperf, now;
1221 	int32_t cpu_load;
1222 
1223 	cummulative_iowait = get_cpu_iowait_time_us(cpu->cpu, &now);
1224 
1225 	/*
1226 	 * Convert iowait time into number of IO cycles spent at max_freq.
1227 	 * IO is considered as busy only for the cpu_load algorithm. For
1228 	 * performance this is not needed since we always try to reach the
1229 	 * maximum P-State, so we are already boosting the IOs.
1230 	 */
1231 	delta_iowait_us = cummulative_iowait - cpu->prev_cummulative_iowait;
1232 	delta_iowait_mperf = div64_u64(delta_iowait_us * cpu->pstate.scaling *
1233 		cpu->pstate.max_pstate, MSEC_PER_SEC);
1234 
1235 	mperf = cpu->sample.mperf + delta_iowait_mperf;
1236 	cpu->prev_cummulative_iowait = cummulative_iowait;
1237 
1238 	/*
1239 	 * The load can be estimated as the ratio of the mperf counter
1240 	 * running at a constant frequency during active periods
1241 	 * (C0) and the time stamp counter running at the same frequency
1242 	 * also during C-states.
1243 	 */
1244 	cpu_load = div64_u64(int_tofp(100) * mperf, sample->tsc);
1245 	cpu->sample.busy_scaled = cpu_load;
1246 
1247 	return get_avg_pstate(cpu) - pid_calc(&cpu->pid, cpu_load);
1248 }
1249 
1250 static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu)
1251 {
1252 	int32_t core_busy, max_pstate, current_pstate, sample_ratio;
1253 	u64 duration_ns;
1254 
1255 	/*
1256 	 * core_busy is the ratio of actual performance to max
1257 	 * max_pstate is the max non turbo pstate available
1258 	 * current_pstate was the pstate that was requested during
1259 	 * 	the last sample period.
1260 	 *
1261 	 * We normalize core_busy, which was our actual percent
1262 	 * performance to what we requested during the last sample
1263 	 * period. The result will be a percentage of busy at a
1264 	 * specified pstate.
1265 	 */
1266 	core_busy = cpu->sample.core_pct_busy;
1267 	max_pstate = cpu->pstate.max_pstate_physical;
1268 	current_pstate = cpu->pstate.current_pstate;
1269 	core_busy = mul_fp(core_busy, div_fp(max_pstate, current_pstate));
1270 
1271 	/*
1272 	 * Since our utilization update callback will not run unless we are
1273 	 * in C0, check if the actual elapsed time is significantly greater (3x)
1274 	 * than our sample interval.  If it is, then we were idle for a long
1275 	 * enough period of time to adjust our busyness.
1276 	 */
1277 	duration_ns = cpu->sample.time - cpu->last_sample_time;
1278 	if ((s64)duration_ns > pid_params.sample_rate_ns * 3) {
1279 		sample_ratio = div_fp(pid_params.sample_rate_ns, duration_ns);
1280 		core_busy = mul_fp(core_busy, sample_ratio);
1281 	} else {
1282 		sample_ratio = div_fp(100 * cpu->sample.mperf, cpu->sample.tsc);
1283 		if (sample_ratio < int_tofp(1))
1284 			core_busy = 0;
1285 	}
1286 
1287 	cpu->sample.busy_scaled = core_busy;
1288 	return cpu->pstate.current_pstate - pid_calc(&cpu->pid, core_busy);
1289 }
1290 
1291 static inline void intel_pstate_update_pstate(struct cpudata *cpu, int pstate)
1292 {
1293 	int max_perf, min_perf;
1294 
1295 	update_turbo_state();
1296 
1297 	intel_pstate_get_min_max(cpu, &min_perf, &max_perf);
1298 	pstate = clamp_t(int, pstate, min_perf, max_perf);
1299 	if (pstate == cpu->pstate.current_pstate)
1300 		return;
1301 
1302 	intel_pstate_record_pstate(cpu, pstate);
1303 	wrmsrl(MSR_IA32_PERF_CTL, pstate_funcs.get_val(cpu, pstate));
1304 }
1305 
1306 static inline void intel_pstate_adjust_busy_pstate(struct cpudata *cpu)
1307 {
1308 	int from, target_pstate;
1309 	struct sample *sample;
1310 
1311 	from = cpu->pstate.current_pstate;
1312 
1313 	target_pstate = pstate_funcs.get_target_pstate(cpu);
1314 
1315 	intel_pstate_update_pstate(cpu, target_pstate);
1316 
1317 	sample = &cpu->sample;
1318 	trace_pstate_sample(fp_toint(sample->core_pct_busy),
1319 		fp_toint(sample->busy_scaled),
1320 		from,
1321 		cpu->pstate.current_pstate,
1322 		sample->mperf,
1323 		sample->aperf,
1324 		sample->tsc,
1325 		get_avg_frequency(cpu));
1326 }
1327 
1328 static void intel_pstate_update_util(struct update_util_data *data, u64 time,
1329 				     unsigned long util, unsigned long max)
1330 {
1331 	struct cpudata *cpu = container_of(data, struct cpudata, update_util);
1332 	u64 delta_ns = time - cpu->sample.time;
1333 
1334 	if ((s64)delta_ns >= pid_params.sample_rate_ns) {
1335 		bool sample_taken = intel_pstate_sample(cpu, time);
1336 
1337 		if (sample_taken) {
1338 			intel_pstate_calc_busy(cpu);
1339 			if (!hwp_active)
1340 				intel_pstate_adjust_busy_pstate(cpu);
1341 		}
1342 	}
1343 }
1344 
1345 #define ICPU(model, policy) \
1346 	{ X86_VENDOR_INTEL, 6, model, X86_FEATURE_APERFMPERF,\
1347 			(unsigned long)&policy }
1348 
1349 static const struct x86_cpu_id intel_pstate_cpu_ids[] = {
1350 	ICPU(0x2a, core_params),
1351 	ICPU(0x2d, core_params),
1352 	ICPU(0x37, silvermont_params),
1353 	ICPU(0x3a, core_params),
1354 	ICPU(0x3c, core_params),
1355 	ICPU(0x3d, core_params),
1356 	ICPU(0x3e, core_params),
1357 	ICPU(0x3f, core_params),
1358 	ICPU(0x45, core_params),
1359 	ICPU(0x46, core_params),
1360 	ICPU(0x47, core_params),
1361 	ICPU(0x4c, airmont_params),
1362 	ICPU(0x4e, core_params),
1363 	ICPU(0x4f, core_params),
1364 	ICPU(0x5e, core_params),
1365 	ICPU(0x56, core_params),
1366 	ICPU(0x57, knl_params),
1367 	{}
1368 };
1369 MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
1370 
1371 static const struct x86_cpu_id intel_pstate_cpu_oob_ids[] = {
1372 	ICPU(0x56, core_params),
1373 	{}
1374 };
1375 
1376 static int intel_pstate_init_cpu(unsigned int cpunum)
1377 {
1378 	struct cpudata *cpu;
1379 
1380 	if (!all_cpu_data[cpunum])
1381 		all_cpu_data[cpunum] = kzalloc(sizeof(struct cpudata),
1382 					       GFP_KERNEL);
1383 	if (!all_cpu_data[cpunum])
1384 		return -ENOMEM;
1385 
1386 	cpu = all_cpu_data[cpunum];
1387 
1388 	cpu->cpu = cpunum;
1389 
1390 	if (hwp_active) {
1391 		intel_pstate_hwp_enable(cpu);
1392 		pid_params.sample_rate_ms = 50;
1393 		pid_params.sample_rate_ns = 50 * NSEC_PER_MSEC;
1394 	}
1395 
1396 	intel_pstate_get_cpu_pstates(cpu);
1397 
1398 	intel_pstate_busy_pid_reset(cpu);
1399 
1400 	pr_debug("controlling: cpu %d\n", cpunum);
1401 
1402 	return 0;
1403 }
1404 
1405 static unsigned int intel_pstate_get(unsigned int cpu_num)
1406 {
1407 	struct cpudata *cpu = all_cpu_data[cpu_num];
1408 
1409 	return cpu ? get_avg_frequency(cpu) : 0;
1410 }
1411 
1412 static void intel_pstate_set_update_util_hook(unsigned int cpu_num)
1413 {
1414 	struct cpudata *cpu = all_cpu_data[cpu_num];
1415 
1416 	/* Prevent intel_pstate_update_util() from using stale data. */
1417 	cpu->sample.time = 0;
1418 	cpufreq_add_update_util_hook(cpu_num, &cpu->update_util,
1419 				     intel_pstate_update_util);
1420 }
1421 
1422 static void intel_pstate_clear_update_util_hook(unsigned int cpu)
1423 {
1424 	cpufreq_remove_update_util_hook(cpu);
1425 	synchronize_sched();
1426 }
1427 
1428 static void intel_pstate_set_performance_limits(struct perf_limits *limits)
1429 {
1430 	limits->no_turbo = 0;
1431 	limits->turbo_disabled = 0;
1432 	limits->max_perf_pct = 100;
1433 	limits->max_perf = int_tofp(1);
1434 	limits->min_perf_pct = 100;
1435 	limits->min_perf = int_tofp(1);
1436 	limits->max_policy_pct = 100;
1437 	limits->max_sysfs_pct = 100;
1438 	limits->min_policy_pct = 0;
1439 	limits->min_sysfs_pct = 0;
1440 }
1441 
1442 static int intel_pstate_set_policy(struct cpufreq_policy *policy)
1443 {
1444 	struct cpudata *cpu;
1445 
1446 	if (!policy->cpuinfo.max_freq)
1447 		return -ENODEV;
1448 
1449 	intel_pstate_clear_update_util_hook(policy->cpu);
1450 
1451 	cpu = all_cpu_data[0];
1452 	if (cpu->pstate.max_pstate_physical > cpu->pstate.max_pstate) {
1453 		if (policy->max < policy->cpuinfo.max_freq &&
1454 		    policy->max > cpu->pstate.max_pstate * cpu->pstate.scaling) {
1455 			pr_debug("policy->max > max non turbo frequency\n");
1456 			policy->max = policy->cpuinfo.max_freq;
1457 		}
1458 	}
1459 
1460 	if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) {
1461 		limits = &performance_limits;
1462 		if (policy->max >= policy->cpuinfo.max_freq) {
1463 			pr_debug("set performance\n");
1464 			intel_pstate_set_performance_limits(limits);
1465 			goto out;
1466 		}
1467 	} else {
1468 		pr_debug("set powersave\n");
1469 		limits = &powersave_limits;
1470 	}
1471 
1472 	limits->min_policy_pct = (policy->min * 100) / policy->cpuinfo.max_freq;
1473 	limits->min_policy_pct = clamp_t(int, limits->min_policy_pct, 0 , 100);
1474 	limits->max_policy_pct = DIV_ROUND_UP(policy->max * 100,
1475 					      policy->cpuinfo.max_freq);
1476 	limits->max_policy_pct = clamp_t(int, limits->max_policy_pct, 0 , 100);
1477 
1478 	/* Normalize user input to [min_policy_pct, max_policy_pct] */
1479 	limits->min_perf_pct = max(limits->min_policy_pct,
1480 				   limits->min_sysfs_pct);
1481 	limits->min_perf_pct = min(limits->max_policy_pct,
1482 				   limits->min_perf_pct);
1483 	limits->max_perf_pct = min(limits->max_policy_pct,
1484 				   limits->max_sysfs_pct);
1485 	limits->max_perf_pct = max(limits->min_policy_pct,
1486 				   limits->max_perf_pct);
1487 	limits->max_perf = round_up(limits->max_perf, FRAC_BITS);
1488 
1489 	/* Make sure min_perf_pct <= max_perf_pct */
1490 	limits->min_perf_pct = min(limits->max_perf_pct, limits->min_perf_pct);
1491 
1492 	limits->min_perf = div_fp(limits->min_perf_pct, 100);
1493 	limits->max_perf = div_fp(limits->max_perf_pct, 100);
1494 
1495  out:
1496 	intel_pstate_set_update_util_hook(policy->cpu);
1497 
1498 	intel_pstate_hwp_set_policy(policy);
1499 
1500 	return 0;
1501 }
1502 
1503 static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
1504 {
1505 	cpufreq_verify_within_cpu_limits(policy);
1506 
1507 	if (policy->policy != CPUFREQ_POLICY_POWERSAVE &&
1508 	    policy->policy != CPUFREQ_POLICY_PERFORMANCE)
1509 		return -EINVAL;
1510 
1511 	return 0;
1512 }
1513 
1514 static void intel_pstate_stop_cpu(struct cpufreq_policy *policy)
1515 {
1516 	int cpu_num = policy->cpu;
1517 	struct cpudata *cpu = all_cpu_data[cpu_num];
1518 
1519 	pr_debug("CPU %d exiting\n", cpu_num);
1520 
1521 	intel_pstate_clear_update_util_hook(cpu_num);
1522 
1523 	if (hwp_active)
1524 		return;
1525 
1526 	intel_pstate_set_min_pstate(cpu);
1527 }
1528 
1529 static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
1530 {
1531 	struct cpudata *cpu;
1532 	int rc;
1533 
1534 	rc = intel_pstate_init_cpu(policy->cpu);
1535 	if (rc)
1536 		return rc;
1537 
1538 	cpu = all_cpu_data[policy->cpu];
1539 
1540 	if (limits->min_perf_pct == 100 && limits->max_perf_pct == 100)
1541 		policy->policy = CPUFREQ_POLICY_PERFORMANCE;
1542 	else
1543 		policy->policy = CPUFREQ_POLICY_POWERSAVE;
1544 
1545 	policy->min = cpu->pstate.min_pstate * cpu->pstate.scaling;
1546 	policy->max = cpu->pstate.turbo_pstate * cpu->pstate.scaling;
1547 
1548 	/* cpuinfo and default policy values */
1549 	policy->cpuinfo.min_freq = cpu->pstate.min_pstate * cpu->pstate.scaling;
1550 	policy->cpuinfo.max_freq =
1551 		cpu->pstate.turbo_pstate * cpu->pstate.scaling;
1552 	intel_pstate_init_acpi_perf_limits(policy);
1553 	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
1554 	cpumask_set_cpu(policy->cpu, policy->cpus);
1555 
1556 	return 0;
1557 }
1558 
1559 static int intel_pstate_cpu_exit(struct cpufreq_policy *policy)
1560 {
1561 	intel_pstate_exit_perf_limits(policy);
1562 
1563 	return 0;
1564 }
1565 
1566 static struct cpufreq_driver intel_pstate_driver = {
1567 	.flags		= CPUFREQ_CONST_LOOPS,
1568 	.verify		= intel_pstate_verify_policy,
1569 	.setpolicy	= intel_pstate_set_policy,
1570 	.resume		= intel_pstate_hwp_set_policy,
1571 	.get		= intel_pstate_get,
1572 	.init		= intel_pstate_cpu_init,
1573 	.exit		= intel_pstate_cpu_exit,
1574 	.stop_cpu	= intel_pstate_stop_cpu,
1575 	.name		= "intel_pstate",
1576 };
1577 
1578 static int __initdata no_load;
1579 static int __initdata no_hwp;
1580 static int __initdata hwp_only;
1581 static unsigned int force_load;
1582 
1583 static int intel_pstate_msrs_not_valid(void)
1584 {
1585 	if (!pstate_funcs.get_max() ||
1586 	    !pstate_funcs.get_min() ||
1587 	    !pstate_funcs.get_turbo())
1588 		return -ENODEV;
1589 
1590 	return 0;
1591 }
1592 
1593 static void copy_pid_params(struct pstate_adjust_policy *policy)
1594 {
1595 	pid_params.sample_rate_ms = policy->sample_rate_ms;
1596 	pid_params.sample_rate_ns = pid_params.sample_rate_ms * NSEC_PER_MSEC;
1597 	pid_params.p_gain_pct = policy->p_gain_pct;
1598 	pid_params.i_gain_pct = policy->i_gain_pct;
1599 	pid_params.d_gain_pct = policy->d_gain_pct;
1600 	pid_params.deadband = policy->deadband;
1601 	pid_params.setpoint = policy->setpoint;
1602 }
1603 
1604 static void copy_cpu_funcs(struct pstate_funcs *funcs)
1605 {
1606 	pstate_funcs.get_max   = funcs->get_max;
1607 	pstate_funcs.get_max_physical = funcs->get_max_physical;
1608 	pstate_funcs.get_min   = funcs->get_min;
1609 	pstate_funcs.get_turbo = funcs->get_turbo;
1610 	pstate_funcs.get_scaling = funcs->get_scaling;
1611 	pstate_funcs.get_val   = funcs->get_val;
1612 	pstate_funcs.get_vid   = funcs->get_vid;
1613 	pstate_funcs.get_target_pstate = funcs->get_target_pstate;
1614 
1615 }
1616 
1617 #ifdef CONFIG_ACPI
1618 
1619 static bool intel_pstate_no_acpi_pss(void)
1620 {
1621 	int i;
1622 
1623 	for_each_possible_cpu(i) {
1624 		acpi_status status;
1625 		union acpi_object *pss;
1626 		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1627 		struct acpi_processor *pr = per_cpu(processors, i);
1628 
1629 		if (!pr)
1630 			continue;
1631 
1632 		status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
1633 		if (ACPI_FAILURE(status))
1634 			continue;
1635 
1636 		pss = buffer.pointer;
1637 		if (pss && pss->type == ACPI_TYPE_PACKAGE) {
1638 			kfree(pss);
1639 			return false;
1640 		}
1641 
1642 		kfree(pss);
1643 	}
1644 
1645 	return true;
1646 }
1647 
1648 static bool intel_pstate_has_acpi_ppc(void)
1649 {
1650 	int i;
1651 
1652 	for_each_possible_cpu(i) {
1653 		struct acpi_processor *pr = per_cpu(processors, i);
1654 
1655 		if (!pr)
1656 			continue;
1657 		if (acpi_has_method(pr->handle, "_PPC"))
1658 			return true;
1659 	}
1660 	return false;
1661 }
1662 
1663 enum {
1664 	PSS,
1665 	PPC,
1666 };
1667 
1668 struct hw_vendor_info {
1669 	u16  valid;
1670 	char oem_id[ACPI_OEM_ID_SIZE];
1671 	char oem_table_id[ACPI_OEM_TABLE_ID_SIZE];
1672 	int  oem_pwr_table;
1673 };
1674 
1675 /* Hardware vendor-specific info that has its own power management modes */
1676 static struct hw_vendor_info vendor_info[] = {
1677 	{1, "HP    ", "ProLiant", PSS},
1678 	{1, "ORACLE", "X4-2    ", PPC},
1679 	{1, "ORACLE", "X4-2L   ", PPC},
1680 	{1, "ORACLE", "X4-2B   ", PPC},
1681 	{1, "ORACLE", "X3-2    ", PPC},
1682 	{1, "ORACLE", "X3-2L   ", PPC},
1683 	{1, "ORACLE", "X3-2B   ", PPC},
1684 	{1, "ORACLE", "X4470M2 ", PPC},
1685 	{1, "ORACLE", "X4270M3 ", PPC},
1686 	{1, "ORACLE", "X4270M2 ", PPC},
1687 	{1, "ORACLE", "X4170M2 ", PPC},
1688 	{1, "ORACLE", "X4170 M3", PPC},
1689 	{1, "ORACLE", "X4275 M3", PPC},
1690 	{1, "ORACLE", "X6-2    ", PPC},
1691 	{1, "ORACLE", "Sudbury ", PPC},
1692 	{0, "", ""},
1693 };
1694 
1695 static bool intel_pstate_platform_pwr_mgmt_exists(void)
1696 {
1697 	struct acpi_table_header hdr;
1698 	struct hw_vendor_info *v_info;
1699 	const struct x86_cpu_id *id;
1700 	u64 misc_pwr;
1701 
1702 	id = x86_match_cpu(intel_pstate_cpu_oob_ids);
1703 	if (id) {
1704 		rdmsrl(MSR_MISC_PWR_MGMT, misc_pwr);
1705 		if ( misc_pwr & (1 << 8))
1706 			return true;
1707 	}
1708 
1709 	if (acpi_disabled ||
1710 	    ACPI_FAILURE(acpi_get_table_header(ACPI_SIG_FADT, 0, &hdr)))
1711 		return false;
1712 
1713 	for (v_info = vendor_info; v_info->valid; v_info++) {
1714 		if (!strncmp(hdr.oem_id, v_info->oem_id, ACPI_OEM_ID_SIZE) &&
1715 			!strncmp(hdr.oem_table_id, v_info->oem_table_id,
1716 						ACPI_OEM_TABLE_ID_SIZE))
1717 			switch (v_info->oem_pwr_table) {
1718 			case PSS:
1719 				return intel_pstate_no_acpi_pss();
1720 			case PPC:
1721 				return intel_pstate_has_acpi_ppc() &&
1722 					(!force_load);
1723 			}
1724 	}
1725 
1726 	return false;
1727 }
1728 #else /* CONFIG_ACPI not enabled */
1729 static inline bool intel_pstate_platform_pwr_mgmt_exists(void) { return false; }
1730 static inline bool intel_pstate_has_acpi_ppc(void) { return false; }
1731 #endif /* CONFIG_ACPI */
1732 
1733 static const struct x86_cpu_id hwp_support_ids[] __initconst = {
1734 	{ X86_VENDOR_INTEL, 6, X86_MODEL_ANY, X86_FEATURE_HWP },
1735 	{}
1736 };
1737 
1738 static int __init intel_pstate_init(void)
1739 {
1740 	int cpu, rc = 0;
1741 	const struct x86_cpu_id *id;
1742 	struct cpu_defaults *cpu_def;
1743 
1744 	if (no_load)
1745 		return -ENODEV;
1746 
1747 	if (x86_match_cpu(hwp_support_ids) && !no_hwp) {
1748 		copy_cpu_funcs(&core_params.funcs);
1749 		hwp_active++;
1750 		goto hwp_cpu_matched;
1751 	}
1752 
1753 	id = x86_match_cpu(intel_pstate_cpu_ids);
1754 	if (!id)
1755 		return -ENODEV;
1756 
1757 	cpu_def = (struct cpu_defaults *)id->driver_data;
1758 
1759 	copy_pid_params(&cpu_def->pid_policy);
1760 	copy_cpu_funcs(&cpu_def->funcs);
1761 
1762 	if (intel_pstate_msrs_not_valid())
1763 		return -ENODEV;
1764 
1765 hwp_cpu_matched:
1766 	/*
1767 	 * The Intel pstate driver will be ignored if the platform
1768 	 * firmware has its own power management modes.
1769 	 */
1770 	if (intel_pstate_platform_pwr_mgmt_exists())
1771 		return -ENODEV;
1772 
1773 	pr_info("Intel P-state driver initializing\n");
1774 
1775 	all_cpu_data = vzalloc(sizeof(void *) * num_possible_cpus());
1776 	if (!all_cpu_data)
1777 		return -ENOMEM;
1778 
1779 	if (!hwp_active && hwp_only)
1780 		goto out;
1781 
1782 	rc = cpufreq_register_driver(&intel_pstate_driver);
1783 	if (rc)
1784 		goto out;
1785 
1786 	intel_pstate_debug_expose_params();
1787 	intel_pstate_sysfs_expose_params();
1788 
1789 	if (hwp_active)
1790 		pr_info("HWP enabled\n");
1791 
1792 	return rc;
1793 out:
1794 	get_online_cpus();
1795 	for_each_online_cpu(cpu) {
1796 		if (all_cpu_data[cpu]) {
1797 			intel_pstate_clear_update_util_hook(cpu);
1798 			kfree(all_cpu_data[cpu]);
1799 		}
1800 	}
1801 
1802 	put_online_cpus();
1803 	vfree(all_cpu_data);
1804 	return -ENODEV;
1805 }
1806 device_initcall(intel_pstate_init);
1807 
1808 static int __init intel_pstate_setup(char *str)
1809 {
1810 	if (!str)
1811 		return -EINVAL;
1812 
1813 	if (!strcmp(str, "disable"))
1814 		no_load = 1;
1815 	if (!strcmp(str, "no_hwp")) {
1816 		pr_info("HWP disabled\n");
1817 		no_hwp = 1;
1818 	}
1819 	if (!strcmp(str, "force"))
1820 		force_load = 1;
1821 	if (!strcmp(str, "hwp_only"))
1822 		hwp_only = 1;
1823 
1824 #ifdef CONFIG_ACPI
1825 	if (!strcmp(str, "support_acpi_ppc"))
1826 		acpi_ppc = true;
1827 #endif
1828 
1829 	return 0;
1830 }
1831 early_param("intel_pstate", intel_pstate_setup);
1832 
1833 MODULE_AUTHOR("Dirk Brandewie <dirk.j.brandewie@intel.com>");
1834 MODULE_DESCRIPTION("'intel_pstate' - P state driver Intel Core processors");
1835 MODULE_LICENSE("GPL");
1836