1  // SPDX-License-Identifier: GPL-2.0-or-later
2  /*
3   * processor_throttling.c - Throttling submodule of the ACPI processor driver
4   *
5   *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6   *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7   *  Copyright (C) 2004       Dominik Brodowski <linux@brodo.de>
8   *  Copyright (C) 2004  Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
9   *                      - Added processor hotplug support
10   */
11  
12  #define pr_fmt(fmt) "ACPI: " fmt
13  
14  #include <linux/kernel.h>
15  #include <linux/module.h>
16  #include <linux/slab.h>
17  #include <linux/init.h>
18  #include <linux/sched.h>
19  #include <linux/cpufreq.h>
20  #include <linux/acpi.h>
21  #include <acpi/processor.h>
22  #include <asm/io.h>
23  #include <linux/uaccess.h>
24  
25  /* ignore_tpc:
26   *  0 -> acpi processor driver doesn't ignore _TPC values
27   *  1 -> acpi processor driver ignores _TPC values
28   */
29  static int ignore_tpc;
30  module_param(ignore_tpc, int, 0644);
31  MODULE_PARM_DESC(ignore_tpc, "Disable broken BIOS _TPC throttling support");
32  
33  struct throttling_tstate {
34  	unsigned int cpu;		/* cpu nr */
35  	int target_state;		/* target T-state */
36  };
37  
38  struct acpi_processor_throttling_arg {
39  	struct acpi_processor *pr;
40  	int target_state;
41  	bool force;
42  };
43  
44  #define THROTTLING_PRECHANGE       (1)
45  #define THROTTLING_POSTCHANGE      (2)
46  
47  static int acpi_processor_get_throttling(struct acpi_processor *pr);
48  static int __acpi_processor_set_throttling(struct acpi_processor *pr,
49  					   int state, bool force, bool direct);
50  
acpi_processor_update_tsd_coord(void)51  static int acpi_processor_update_tsd_coord(void)
52  {
53  	int count_target;
54  	int retval = 0;
55  	unsigned int i, j;
56  	cpumask_var_t covered_cpus;
57  	struct acpi_processor *pr, *match_pr;
58  	struct acpi_tsd_package *pdomain, *match_pdomain;
59  	struct acpi_processor_throttling *pthrottling, *match_pthrottling;
60  
61  	if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL))
62  		return -ENOMEM;
63  
64  	/*
65  	 * Now that we have _TSD data from all CPUs, lets setup T-state
66  	 * coordination between all CPUs.
67  	 */
68  	for_each_possible_cpu(i) {
69  		pr = per_cpu(processors, i);
70  		if (!pr)
71  			continue;
72  
73  		/* Basic validity check for domain info */
74  		pthrottling = &(pr->throttling);
75  
76  		/*
77  		 * If tsd package for one cpu is invalid, the coordination
78  		 * among all CPUs is thought as invalid.
79  		 * Maybe it is ugly.
80  		 */
81  		if (!pthrottling->tsd_valid_flag) {
82  			retval = -EINVAL;
83  			break;
84  		}
85  	}
86  	if (retval)
87  		goto err_ret;
88  
89  	for_each_possible_cpu(i) {
90  		pr = per_cpu(processors, i);
91  		if (!pr)
92  			continue;
93  
94  		if (cpumask_test_cpu(i, covered_cpus))
95  			continue;
96  		pthrottling = &pr->throttling;
97  
98  		pdomain = &(pthrottling->domain_info);
99  		cpumask_set_cpu(i, pthrottling->shared_cpu_map);
100  		cpumask_set_cpu(i, covered_cpus);
101  		/*
102  		 * If the number of processor in the TSD domain is 1, it is
103  		 * unnecessary to parse the coordination for this CPU.
104  		 */
105  		if (pdomain->num_processors <= 1)
106  			continue;
107  
108  		/* Validate the Domain info */
109  		count_target = pdomain->num_processors;
110  
111  		for_each_possible_cpu(j) {
112  			if (i == j)
113  				continue;
114  
115  			match_pr = per_cpu(processors, j);
116  			if (!match_pr)
117  				continue;
118  
119  			match_pthrottling = &(match_pr->throttling);
120  			match_pdomain = &(match_pthrottling->domain_info);
121  			if (match_pdomain->domain != pdomain->domain)
122  				continue;
123  
124  			/* Here i and j are in the same domain.
125  			 * If two TSD packages have the same domain, they
126  			 * should have the same num_porcessors and
127  			 * coordination type. Otherwise it will be regarded
128  			 * as illegal.
129  			 */
130  			if (match_pdomain->num_processors != count_target) {
131  				retval = -EINVAL;
132  				goto err_ret;
133  			}
134  
135  			if (pdomain->coord_type != match_pdomain->coord_type) {
136  				retval = -EINVAL;
137  				goto err_ret;
138  			}
139  
140  			cpumask_set_cpu(j, covered_cpus);
141  			cpumask_set_cpu(j, pthrottling->shared_cpu_map);
142  		}
143  		for_each_possible_cpu(j) {
144  			if (i == j)
145  				continue;
146  
147  			match_pr = per_cpu(processors, j);
148  			if (!match_pr)
149  				continue;
150  
151  			match_pthrottling = &(match_pr->throttling);
152  			match_pdomain = &(match_pthrottling->domain_info);
153  			if (match_pdomain->domain != pdomain->domain)
154  				continue;
155  
156  			/*
157  			 * If some CPUS have the same domain, they
158  			 * will have the same shared_cpu_map.
159  			 */
160  			cpumask_copy(match_pthrottling->shared_cpu_map,
161  				     pthrottling->shared_cpu_map);
162  		}
163  	}
164  
165  err_ret:
166  	free_cpumask_var(covered_cpus);
167  
168  	for_each_possible_cpu(i) {
169  		pr = per_cpu(processors, i);
170  		if (!pr)
171  			continue;
172  
173  		/*
174  		 * Assume no coordination on any error parsing domain info.
175  		 * The coordination type will be forced as SW_ALL.
176  		 */
177  		if (retval) {
178  			pthrottling = &(pr->throttling);
179  			cpumask_clear(pthrottling->shared_cpu_map);
180  			cpumask_set_cpu(i, pthrottling->shared_cpu_map);
181  			pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
182  		}
183  	}
184  
185  	return retval;
186  }
187  
188  /*
189   * Update the T-state coordination after the _TSD
190   * data for all cpus is obtained.
191   */
acpi_processor_throttling_init(void)192  void acpi_processor_throttling_init(void)
193  {
194  	if (acpi_processor_update_tsd_coord())
195  		pr_debug("Assume no T-state coordination\n");
196  }
197  
acpi_processor_throttling_notifier(unsigned long event,void * data)198  static int acpi_processor_throttling_notifier(unsigned long event, void *data)
199  {
200  	struct throttling_tstate *p_tstate = data;
201  	struct acpi_processor *pr;
202  	unsigned int cpu;
203  	int target_state;
204  	struct acpi_processor_limit *p_limit;
205  	struct acpi_processor_throttling *p_throttling;
206  
207  	cpu = p_tstate->cpu;
208  	pr = per_cpu(processors, cpu);
209  	if (!pr) {
210  		pr_debug("Invalid pr pointer\n");
211  		return 0;
212  	}
213  	if (!pr->flags.throttling) {
214  		acpi_handle_debug(pr->handle,
215  				  "Throttling control unsupported on CPU %d\n",
216  				  cpu);
217  		return 0;
218  	}
219  	target_state = p_tstate->target_state;
220  	p_throttling = &(pr->throttling);
221  	switch (event) {
222  	case THROTTLING_PRECHANGE:
223  		/*
224  		 * Prechange event is used to choose one proper t-state,
225  		 * which meets the limits of thermal, user and _TPC.
226  		 */
227  		p_limit = &pr->limit;
228  		if (p_limit->thermal.tx > target_state)
229  			target_state = p_limit->thermal.tx;
230  		if (p_limit->user.tx > target_state)
231  			target_state = p_limit->user.tx;
232  		if (pr->throttling_platform_limit > target_state)
233  			target_state = pr->throttling_platform_limit;
234  		if (target_state >= p_throttling->state_count) {
235  			pr_warn("Exceed the limit of T-state \n");
236  			target_state = p_throttling->state_count - 1;
237  		}
238  		p_tstate->target_state = target_state;
239  		acpi_handle_debug(pr->handle,
240  				  "PreChange Event: target T-state of CPU %d is T%d\n",
241  				  cpu, target_state);
242  		break;
243  	case THROTTLING_POSTCHANGE:
244  		/*
245  		 * Postchange event is only used to update the
246  		 * T-state flag of acpi_processor_throttling.
247  		 */
248  		p_throttling->state = target_state;
249  		acpi_handle_debug(pr->handle,
250  				  "PostChange Event: CPU %d is switched to T%d\n",
251  				  cpu, target_state);
252  		break;
253  	default:
254  		pr_warn("Unsupported Throttling notifier event\n");
255  		break;
256  	}
257  
258  	return 0;
259  }
260  
261  /*
262   * _TPC - Throttling Present Capabilities
263   */
acpi_processor_get_platform_limit(struct acpi_processor * pr)264  static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
265  {
266  	acpi_status status = 0;
267  	unsigned long long tpc = 0;
268  
269  	if (!pr)
270  		return -EINVAL;
271  
272  	if (ignore_tpc)
273  		goto end;
274  
275  	status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
276  	if (ACPI_FAILURE(status)) {
277  		if (status != AE_NOT_FOUND)
278  			acpi_evaluation_failure_warn(pr->handle, "_TPC", status);
279  
280  		return -ENODEV;
281  	}
282  
283  end:
284  	pr->throttling_platform_limit = (int)tpc;
285  	return 0;
286  }
287  
acpi_processor_tstate_has_changed(struct acpi_processor * pr)288  int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
289  {
290  	int result = 0;
291  	int throttling_limit;
292  	int current_state;
293  	struct acpi_processor_limit *limit;
294  	int target_state;
295  
296  	if (ignore_tpc)
297  		return 0;
298  
299  	result = acpi_processor_get_platform_limit(pr);
300  	if (result) {
301  		/* Throttling Limit is unsupported */
302  		return result;
303  	}
304  
305  	throttling_limit = pr->throttling_platform_limit;
306  	if (throttling_limit >= pr->throttling.state_count) {
307  		/* Uncorrect Throttling Limit */
308  		return -EINVAL;
309  	}
310  
311  	current_state = pr->throttling.state;
312  	if (current_state > throttling_limit) {
313  		/*
314  		 * The current state can meet the requirement of
315  		 * _TPC limit. But it is reasonable that OSPM changes
316  		 * t-states from high to low for better performance.
317  		 * Of course the limit condition of thermal
318  		 * and user should be considered.
319  		 */
320  		limit = &pr->limit;
321  		target_state = throttling_limit;
322  		if (limit->thermal.tx > target_state)
323  			target_state = limit->thermal.tx;
324  		if (limit->user.tx > target_state)
325  			target_state = limit->user.tx;
326  	} else if (current_state == throttling_limit) {
327  		/*
328  		 * Unnecessary to change the throttling state
329  		 */
330  		return 0;
331  	} else {
332  		/*
333  		 * If the current state is lower than the limit of _TPC, it
334  		 * will be forced to switch to the throttling state defined
335  		 * by throttling_platfor_limit.
336  		 * Because the previous state meets with the limit condition
337  		 * of thermal and user, it is unnecessary to check it again.
338  		 */
339  		target_state = throttling_limit;
340  	}
341  	return acpi_processor_set_throttling(pr, target_state, false);
342  }
343  
344  /*
345   * This function is used to reevaluate whether the T-state is valid
346   * after one CPU is onlined/offlined.
347   * It is noted that it won't reevaluate the following properties for
348   * the T-state.
349   *	1. Control method.
350   *	2. the number of supported T-state
351   *	3. TSD domain
352   */
acpi_processor_reevaluate_tstate(struct acpi_processor * pr,bool is_dead)353  void acpi_processor_reevaluate_tstate(struct acpi_processor *pr,
354  					bool is_dead)
355  {
356  	int result = 0;
357  
358  	if (is_dead) {
359  		/* When one CPU is offline, the T-state throttling
360  		 * will be invalidated.
361  		 */
362  		pr->flags.throttling = 0;
363  		return;
364  	}
365  	/* the following is to recheck whether the T-state is valid for
366  	 * the online CPU
367  	 */
368  	if (!pr->throttling.state_count) {
369  		/* If the number of T-state is invalid, it is
370  		 * invalidated.
371  		 */
372  		pr->flags.throttling = 0;
373  		return;
374  	}
375  	pr->flags.throttling = 1;
376  
377  	/* Disable throttling (if enabled).  We'll let subsequent
378  	 * policy (e.g.thermal) decide to lower performance if it
379  	 * so chooses, but for now we'll crank up the speed.
380  	 */
381  
382  	result = acpi_processor_get_throttling(pr);
383  	if (result)
384  		goto end;
385  
386  	if (pr->throttling.state) {
387  		result = acpi_processor_set_throttling(pr, 0, false);
388  		if (result)
389  			goto end;
390  	}
391  
392  end:
393  	if (result)
394  		pr->flags.throttling = 0;
395  }
396  /*
397   * _PTC - Processor Throttling Control (and status) register location
398   */
acpi_processor_get_throttling_control(struct acpi_processor * pr)399  static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
400  {
401  	int result = 0;
402  	acpi_status status = 0;
403  	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
404  	union acpi_object *ptc = NULL;
405  	union acpi_object obj;
406  	struct acpi_processor_throttling *throttling;
407  
408  	status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
409  	if (ACPI_FAILURE(status)) {
410  		if (status != AE_NOT_FOUND)
411  			acpi_evaluation_failure_warn(pr->handle, "_PTC", status);
412  
413  		return -ENODEV;
414  	}
415  
416  	ptc = (union acpi_object *)buffer.pointer;
417  	if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
418  	    || (ptc->package.count != 2)) {
419  		pr_err("Invalid _PTC data\n");
420  		result = -EFAULT;
421  		goto end;
422  	}
423  
424  	/*
425  	 * control_register
426  	 */
427  
428  	obj = ptc->package.elements[0];
429  
430  	if ((obj.type != ACPI_TYPE_BUFFER)
431  	    || (obj.buffer.length < sizeof(struct acpi_ptc_register))
432  	    || (obj.buffer.pointer == NULL)) {
433  		pr_err("Invalid _PTC data (control_register)\n");
434  		result = -EFAULT;
435  		goto end;
436  	}
437  	memcpy(&pr->throttling.control_register, obj.buffer.pointer,
438  	       sizeof(struct acpi_ptc_register));
439  
440  	/*
441  	 * status_register
442  	 */
443  
444  	obj = ptc->package.elements[1];
445  
446  	if ((obj.type != ACPI_TYPE_BUFFER)
447  	    || (obj.buffer.length < sizeof(struct acpi_ptc_register))
448  	    || (obj.buffer.pointer == NULL)) {
449  		pr_err("Invalid _PTC data (status_register)\n");
450  		result = -EFAULT;
451  		goto end;
452  	}
453  
454  	memcpy(&pr->throttling.status_register, obj.buffer.pointer,
455  	       sizeof(struct acpi_ptc_register));
456  
457  	throttling = &pr->throttling;
458  
459  	if ((throttling->control_register.bit_width +
460  		throttling->control_register.bit_offset) > 32) {
461  		pr_err("Invalid _PTC control register\n");
462  		result = -EFAULT;
463  		goto end;
464  	}
465  
466  	if ((throttling->status_register.bit_width +
467  		throttling->status_register.bit_offset) > 32) {
468  		pr_err("Invalid _PTC status register\n");
469  		result = -EFAULT;
470  		goto end;
471  	}
472  
473  end:
474  	kfree(buffer.pointer);
475  
476  	return result;
477  }
478  
479  /*
480   * _TSS - Throttling Supported States
481   */
acpi_processor_get_throttling_states(struct acpi_processor * pr)482  static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
483  {
484  	int result = 0;
485  	acpi_status status = AE_OK;
486  	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
487  	struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
488  	struct acpi_buffer state = { 0, NULL };
489  	union acpi_object *tss = NULL;
490  	int i;
491  
492  	status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
493  	if (ACPI_FAILURE(status)) {
494  		if (status != AE_NOT_FOUND)
495  			acpi_evaluation_failure_warn(pr->handle, "_TSS", status);
496  
497  		return -ENODEV;
498  	}
499  
500  	tss = buffer.pointer;
501  	if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
502  		pr_err("Invalid _TSS data\n");
503  		result = -EFAULT;
504  		goto end;
505  	}
506  
507  	acpi_handle_debug(pr->handle, "Found %d throttling states\n",
508  			  tss->package.count);
509  
510  	pr->throttling.state_count = tss->package.count;
511  	pr->throttling.states_tss =
512  	    kmalloc_array(tss->package.count,
513  			  sizeof(struct acpi_processor_tx_tss),
514  			  GFP_KERNEL);
515  	if (!pr->throttling.states_tss) {
516  		result = -ENOMEM;
517  		goto end;
518  	}
519  
520  	for (i = 0; i < pr->throttling.state_count; i++) {
521  
522  		struct acpi_processor_tx_tss *tx =
523  		    (struct acpi_processor_tx_tss *)&(pr->throttling.
524  						      states_tss[i]);
525  
526  		state.length = sizeof(struct acpi_processor_tx_tss);
527  		state.pointer = tx;
528  
529  		acpi_handle_debug(pr->handle, "Extracting state %d\n", i);
530  
531  		status = acpi_extract_package(&(tss->package.elements[i]),
532  					      &format, &state);
533  		if (ACPI_FAILURE(status)) {
534  			acpi_handle_warn(pr->handle, "Invalid _TSS data: %s\n",
535  					 acpi_format_exception(status));
536  			result = -EFAULT;
537  			kfree(pr->throttling.states_tss);
538  			goto end;
539  		}
540  
541  		if (!tx->freqpercentage) {
542  			pr_err("Invalid _TSS data: freq is zero\n");
543  			result = -EFAULT;
544  			kfree(pr->throttling.states_tss);
545  			goto end;
546  		}
547  	}
548  
549  end:
550  	kfree(buffer.pointer);
551  
552  	return result;
553  }
554  
555  /*
556   * _TSD - T-State Dependencies
557   */
acpi_processor_get_tsd(struct acpi_processor * pr)558  static int acpi_processor_get_tsd(struct acpi_processor *pr)
559  {
560  	int result = 0;
561  	acpi_status status = AE_OK;
562  	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
563  	struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
564  	struct acpi_buffer state = { 0, NULL };
565  	union acpi_object *tsd = NULL;
566  	struct acpi_tsd_package *pdomain;
567  	struct acpi_processor_throttling *pthrottling;
568  
569  	pthrottling = &pr->throttling;
570  	pthrottling->tsd_valid_flag = 0;
571  
572  	status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
573  	if (ACPI_FAILURE(status)) {
574  		if (status != AE_NOT_FOUND)
575  			acpi_evaluation_failure_warn(pr->handle, "_TSD", status);
576  
577  		return -ENODEV;
578  	}
579  
580  	tsd = buffer.pointer;
581  	if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
582  		pr_err("Invalid _TSD data\n");
583  		result = -EFAULT;
584  		goto end;
585  	}
586  
587  	if (tsd->package.count != 1) {
588  		pr_err("Invalid _TSD data\n");
589  		result = -EFAULT;
590  		goto end;
591  	}
592  
593  	pdomain = &(pr->throttling.domain_info);
594  
595  	state.length = sizeof(struct acpi_tsd_package);
596  	state.pointer = pdomain;
597  
598  	status = acpi_extract_package(&(tsd->package.elements[0]),
599  				      &format, &state);
600  	if (ACPI_FAILURE(status)) {
601  		pr_err("Invalid _TSD data\n");
602  		result = -EFAULT;
603  		goto end;
604  	}
605  
606  	if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
607  		pr_err("Unknown _TSD:num_entries\n");
608  		result = -EFAULT;
609  		goto end;
610  	}
611  
612  	if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
613  		pr_err("Unknown _TSD:revision\n");
614  		result = -EFAULT;
615  		goto end;
616  	}
617  
618  	pthrottling = &pr->throttling;
619  	pthrottling->tsd_valid_flag = 1;
620  	pthrottling->shared_type = pdomain->coord_type;
621  	cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
622  	/*
623  	 * If the coordination type is not defined in ACPI spec,
624  	 * the tsd_valid_flag will be clear and coordination type
625  	 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
626  	 */
627  	if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
628  		pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
629  		pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
630  		pthrottling->tsd_valid_flag = 0;
631  		pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
632  	}
633  
634  end:
635  	kfree(buffer.pointer);
636  	return result;
637  }
638  
639  /* --------------------------------------------------------------------------
640                                Throttling Control
641     -------------------------------------------------------------------------- */
acpi_processor_get_throttling_fadt(struct acpi_processor * pr)642  static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
643  {
644  	int state = 0;
645  	u32 value = 0;
646  	u32 duty_mask = 0;
647  	u32 duty_value = 0;
648  
649  	if (!pr)
650  		return -EINVAL;
651  
652  	if (!pr->flags.throttling)
653  		return -ENODEV;
654  
655  	/*
656  	 * We don't care about error returns - we just try to mark
657  	 * these reserved so that nobody else is confused into thinking
658  	 * that this region might be unused..
659  	 *
660  	 * (In particular, allocating the IO range for Cardbus)
661  	 */
662  	request_region(pr->throttling.address, 6, "ACPI CPU throttle");
663  
664  	pr->throttling.state = 0;
665  
666  	duty_mask = pr->throttling.state_count - 1;
667  
668  	duty_mask <<= pr->throttling.duty_offset;
669  
670  	local_irq_disable();
671  
672  	value = inl(pr->throttling.address);
673  
674  	/*
675  	 * Compute the current throttling state when throttling is enabled
676  	 * (bit 4 is on).
677  	 */
678  	if (value & 0x10) {
679  		duty_value = value & duty_mask;
680  		duty_value >>= pr->throttling.duty_offset;
681  
682  		if (duty_value)
683  			state = pr->throttling.state_count - duty_value;
684  	}
685  
686  	pr->throttling.state = state;
687  
688  	local_irq_enable();
689  
690  	acpi_handle_debug(pr->handle,
691  			  "Throttling state is T%d (%d%% throttling applied)\n",
692  			  state, pr->throttling.states[state].performance);
693  
694  	return 0;
695  }
696  
697  #ifdef CONFIG_X86
acpi_throttling_rdmsr(u64 * value)698  static int acpi_throttling_rdmsr(u64 *value)
699  {
700  	u64 msr_high, msr_low;
701  	u64 msr = 0;
702  	int ret = -1;
703  
704  	if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
705  		!this_cpu_has(X86_FEATURE_ACPI)) {
706  		pr_err("HARDWARE addr space,NOT supported yet\n");
707  	} else {
708  		msr_low = 0;
709  		msr_high = 0;
710  		rdmsr_safe(MSR_IA32_THERM_CONTROL,
711  			(u32 *)&msr_low, (u32 *) &msr_high);
712  		msr = (msr_high << 32) | msr_low;
713  		*value = (u64) msr;
714  		ret = 0;
715  	}
716  	return ret;
717  }
718  
acpi_throttling_wrmsr(u64 value)719  static int acpi_throttling_wrmsr(u64 value)
720  {
721  	int ret = -1;
722  	u64 msr;
723  
724  	if ((this_cpu_read(cpu_info.x86_vendor) != X86_VENDOR_INTEL) ||
725  		!this_cpu_has(X86_FEATURE_ACPI)) {
726  		pr_err("HARDWARE addr space,NOT supported yet\n");
727  	} else {
728  		msr = value;
729  		wrmsr_safe(MSR_IA32_THERM_CONTROL,
730  			msr & 0xffffffff, msr >> 32);
731  		ret = 0;
732  	}
733  	return ret;
734  }
735  #else
acpi_throttling_rdmsr(u64 * value)736  static int acpi_throttling_rdmsr(u64 *value)
737  {
738  	pr_err("HARDWARE addr space,NOT supported yet\n");
739  	return -1;
740  }
741  
acpi_throttling_wrmsr(u64 value)742  static int acpi_throttling_wrmsr(u64 value)
743  {
744  	pr_err("HARDWARE addr space,NOT supported yet\n");
745  	return -1;
746  }
747  #endif
748  
acpi_read_throttling_status(struct acpi_processor * pr,u64 * value)749  static int acpi_read_throttling_status(struct acpi_processor *pr,
750  					u64 *value)
751  {
752  	u32 bit_width, bit_offset;
753  	u32 ptc_value;
754  	u64 ptc_mask;
755  	struct acpi_processor_throttling *throttling;
756  	int ret = -1;
757  
758  	throttling = &pr->throttling;
759  	switch (throttling->status_register.space_id) {
760  	case ACPI_ADR_SPACE_SYSTEM_IO:
761  		bit_width = throttling->status_register.bit_width;
762  		bit_offset = throttling->status_register.bit_offset;
763  
764  		acpi_os_read_port((acpi_io_address) throttling->status_register.
765  				  address, &ptc_value,
766  				  (u32) (bit_width + bit_offset));
767  		ptc_mask = (1 << bit_width) - 1;
768  		*value = (u64) ((ptc_value >> bit_offset) & ptc_mask);
769  		ret = 0;
770  		break;
771  	case ACPI_ADR_SPACE_FIXED_HARDWARE:
772  		ret = acpi_throttling_rdmsr(value);
773  		break;
774  	default:
775  		pr_err("Unknown addr space %d\n",
776  		       (u32) (throttling->status_register.space_id));
777  	}
778  	return ret;
779  }
780  
acpi_write_throttling_state(struct acpi_processor * pr,u64 value)781  static int acpi_write_throttling_state(struct acpi_processor *pr,
782  				u64 value)
783  {
784  	u32 bit_width, bit_offset;
785  	u64 ptc_value;
786  	u64 ptc_mask;
787  	struct acpi_processor_throttling *throttling;
788  	int ret = -1;
789  
790  	throttling = &pr->throttling;
791  	switch (throttling->control_register.space_id) {
792  	case ACPI_ADR_SPACE_SYSTEM_IO:
793  		bit_width = throttling->control_register.bit_width;
794  		bit_offset = throttling->control_register.bit_offset;
795  		ptc_mask = (1 << bit_width) - 1;
796  		ptc_value = value & ptc_mask;
797  
798  		acpi_os_write_port((acpi_io_address) throttling->
799  					control_register.address,
800  					(u32) (ptc_value << bit_offset),
801  					(u32) (bit_width + bit_offset));
802  		ret = 0;
803  		break;
804  	case ACPI_ADR_SPACE_FIXED_HARDWARE:
805  		ret = acpi_throttling_wrmsr(value);
806  		break;
807  	default:
808  		pr_err("Unknown addr space %d\n",
809  		       (u32) (throttling->control_register.space_id));
810  	}
811  	return ret;
812  }
813  
acpi_get_throttling_state(struct acpi_processor * pr,u64 value)814  static int acpi_get_throttling_state(struct acpi_processor *pr,
815  				u64 value)
816  {
817  	int i;
818  
819  	for (i = 0; i < pr->throttling.state_count; i++) {
820  		struct acpi_processor_tx_tss *tx =
821  		    (struct acpi_processor_tx_tss *)&(pr->throttling.
822  						      states_tss[i]);
823  		if (tx->control == value)
824  			return i;
825  	}
826  	return -1;
827  }
828  
acpi_get_throttling_value(struct acpi_processor * pr,int state,u64 * value)829  static int acpi_get_throttling_value(struct acpi_processor *pr,
830  			int state, u64 *value)
831  {
832  	int ret = -1;
833  
834  	if (state >= 0 && state <= pr->throttling.state_count) {
835  		struct acpi_processor_tx_tss *tx =
836  		    (struct acpi_processor_tx_tss *)&(pr->throttling.
837  						      states_tss[state]);
838  		*value = tx->control;
839  		ret = 0;
840  	}
841  	return ret;
842  }
843  
acpi_processor_get_throttling_ptc(struct acpi_processor * pr)844  static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
845  {
846  	int state = 0;
847  	int ret;
848  	u64 value;
849  
850  	if (!pr)
851  		return -EINVAL;
852  
853  	if (!pr->flags.throttling)
854  		return -ENODEV;
855  
856  	pr->throttling.state = 0;
857  
858  	value = 0;
859  	ret = acpi_read_throttling_status(pr, &value);
860  	if (ret >= 0) {
861  		state = acpi_get_throttling_state(pr, value);
862  		if (state == -1) {
863  			acpi_handle_debug(pr->handle,
864  					  "Invalid throttling state, reset\n");
865  			state = 0;
866  			ret = __acpi_processor_set_throttling(pr, state, true,
867  							      true);
868  			if (ret)
869  				return ret;
870  		}
871  		pr->throttling.state = state;
872  	}
873  
874  	return 0;
875  }
876  
__acpi_processor_get_throttling(void * data)877  static long __acpi_processor_get_throttling(void *data)
878  {
879  	struct acpi_processor *pr = data;
880  
881  	return pr->throttling.acpi_processor_get_throttling(pr);
882  }
883  
acpi_processor_get_throttling(struct acpi_processor * pr)884  static int acpi_processor_get_throttling(struct acpi_processor *pr)
885  {
886  	if (!pr)
887  		return -EINVAL;
888  
889  	if (!pr->flags.throttling)
890  		return -ENODEV;
891  
892  	/*
893  	 * This is either called from the CPU hotplug callback of
894  	 * processor_driver or via the ACPI probe function. In the latter
895  	 * case the CPU is not guaranteed to be online. Both call sites are
896  	 * protected against CPU hotplug.
897  	 */
898  	if (!cpu_online(pr->id))
899  		return -ENODEV;
900  
901  	return call_on_cpu(pr->id, __acpi_processor_get_throttling, pr, false);
902  }
903  
acpi_processor_get_fadt_info(struct acpi_processor * pr)904  static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
905  {
906  	int i, step;
907  
908  	if (!pr->throttling.address) {
909  		acpi_handle_debug(pr->handle, "No throttling register\n");
910  		return -EINVAL;
911  	} else if (!pr->throttling.duty_width) {
912  		acpi_handle_debug(pr->handle, "No throttling states\n");
913  		return -EINVAL;
914  	}
915  	/* TBD: Support duty_cycle values that span bit 4. */
916  	else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
917  		pr_warn("duty_cycle spans bit 4\n");
918  		return -EINVAL;
919  	}
920  
921  	pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
922  
923  	/*
924  	 * Compute state values. Note that throttling displays a linear power
925  	 * performance relationship (at 50% performance the CPU will consume
926  	 * 50% power).  Values are in 1/10th of a percent to preserve accuracy.
927  	 */
928  
929  	step = (1000 / pr->throttling.state_count);
930  
931  	for (i = 0; i < pr->throttling.state_count; i++) {
932  		pr->throttling.states[i].performance = 1000 - step * i;
933  		pr->throttling.states[i].power = 1000 - step * i;
934  	}
935  	return 0;
936  }
937  
acpi_processor_set_throttling_fadt(struct acpi_processor * pr,int state,bool force)938  static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
939  					      int state, bool force)
940  {
941  	u32 value = 0;
942  	u32 duty_mask = 0;
943  	u32 duty_value = 0;
944  
945  	if (!pr)
946  		return -EINVAL;
947  
948  	if ((state < 0) || (state > (pr->throttling.state_count - 1)))
949  		return -EINVAL;
950  
951  	if (!pr->flags.throttling)
952  		return -ENODEV;
953  
954  	if (!force && (state == pr->throttling.state))
955  		return 0;
956  
957  	if (state < pr->throttling_platform_limit)
958  		return -EPERM;
959  	/*
960  	 * Calculate the duty_value and duty_mask.
961  	 */
962  	if (state) {
963  		duty_value = pr->throttling.state_count - state;
964  
965  		duty_value <<= pr->throttling.duty_offset;
966  
967  		/* Used to clear all duty_value bits */
968  		duty_mask = pr->throttling.state_count - 1;
969  
970  		duty_mask <<= acpi_gbl_FADT.duty_offset;
971  		duty_mask = ~duty_mask;
972  	}
973  
974  	local_irq_disable();
975  
976  	/*
977  	 * Disable throttling by writing a 0 to bit 4.  Note that we must
978  	 * turn it off before you can change the duty_value.
979  	 */
980  	value = inl(pr->throttling.address);
981  	if (value & 0x10) {
982  		value &= 0xFFFFFFEF;
983  		outl(value, pr->throttling.address);
984  	}
985  
986  	/*
987  	 * Write the new duty_value and then enable throttling.  Note
988  	 * that a state value of 0 leaves throttling disabled.
989  	 */
990  	if (state) {
991  		value &= duty_mask;
992  		value |= duty_value;
993  		outl(value, pr->throttling.address);
994  
995  		value |= 0x00000010;
996  		outl(value, pr->throttling.address);
997  	}
998  
999  	pr->throttling.state = state;
1000  
1001  	local_irq_enable();
1002  
1003  	acpi_handle_debug(pr->handle,
1004  			  "Throttling state set to T%d (%d%%)\n", state,
1005  			  (pr->throttling.states[state].performance ? pr->
1006  			   throttling.states[state].performance / 10 : 0));
1007  
1008  	return 0;
1009  }
1010  
acpi_processor_set_throttling_ptc(struct acpi_processor * pr,int state,bool force)1011  static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
1012  					     int state, bool force)
1013  {
1014  	int ret;
1015  	u64 value;
1016  
1017  	if (!pr)
1018  		return -EINVAL;
1019  
1020  	if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1021  		return -EINVAL;
1022  
1023  	if (!pr->flags.throttling)
1024  		return -ENODEV;
1025  
1026  	if (!force && (state == pr->throttling.state))
1027  		return 0;
1028  
1029  	if (state < pr->throttling_platform_limit)
1030  		return -EPERM;
1031  
1032  	value = 0;
1033  	ret = acpi_get_throttling_value(pr, state, &value);
1034  	if (ret >= 0) {
1035  		acpi_write_throttling_state(pr, value);
1036  		pr->throttling.state = state;
1037  	}
1038  
1039  	return 0;
1040  }
1041  
acpi_processor_throttling_fn(void * data)1042  static long acpi_processor_throttling_fn(void *data)
1043  {
1044  	struct acpi_processor_throttling_arg *arg = data;
1045  	struct acpi_processor *pr = arg->pr;
1046  
1047  	return pr->throttling.acpi_processor_set_throttling(pr,
1048  			arg->target_state, arg->force);
1049  }
1050  
__acpi_processor_set_throttling(struct acpi_processor * pr,int state,bool force,bool direct)1051  static int __acpi_processor_set_throttling(struct acpi_processor *pr,
1052  					   int state, bool force, bool direct)
1053  {
1054  	int ret = 0;
1055  	unsigned int i;
1056  	struct acpi_processor *match_pr;
1057  	struct acpi_processor_throttling *p_throttling;
1058  	struct acpi_processor_throttling_arg arg;
1059  	struct throttling_tstate t_state;
1060  
1061  	if (!pr)
1062  		return -EINVAL;
1063  
1064  	if (!pr->flags.throttling)
1065  		return -ENODEV;
1066  
1067  	if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1068  		return -EINVAL;
1069  
1070  	if (cpu_is_offline(pr->id)) {
1071  		/*
1072  		 * the cpu pointed by pr->id is offline. Unnecessary to change
1073  		 * the throttling state any more.
1074  		 */
1075  		return -ENODEV;
1076  	}
1077  
1078  	t_state.target_state = state;
1079  	p_throttling = &(pr->throttling);
1080  
1081  	/*
1082  	 * The throttling notifier will be called for every
1083  	 * affected cpu in order to get one proper T-state.
1084  	 * The notifier event is THROTTLING_PRECHANGE.
1085  	 */
1086  	for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1087  		t_state.cpu = i;
1088  		acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1089  							&t_state);
1090  	}
1091  	/*
1092  	 * The function of acpi_processor_set_throttling will be called
1093  	 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1094  	 * it is necessary to call it for every affected cpu. Otherwise
1095  	 * it can be called only for the cpu pointed by pr.
1096  	 */
1097  	if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1098  		arg.pr = pr;
1099  		arg.target_state = state;
1100  		arg.force = force;
1101  		ret = call_on_cpu(pr->id, acpi_processor_throttling_fn, &arg,
1102  				  direct);
1103  	} else {
1104  		/*
1105  		 * When the T-state coordination is SW_ALL or HW_ALL,
1106  		 * it is necessary to set T-state for every affected
1107  		 * cpus.
1108  		 */
1109  		for_each_cpu_and(i, cpu_online_mask,
1110  		    p_throttling->shared_cpu_map) {
1111  			match_pr = per_cpu(processors, i);
1112  			/*
1113  			 * If the pointer is invalid, we will report the
1114  			 * error message and continue.
1115  			 */
1116  			if (!match_pr) {
1117  				acpi_handle_debug(pr->handle,
1118  					"Invalid Pointer for CPU %d\n", i);
1119  				continue;
1120  			}
1121  			/*
1122  			 * If the throttling control is unsupported on CPU i,
1123  			 * we will report the error message and continue.
1124  			 */
1125  			if (!match_pr->flags.throttling) {
1126  				acpi_handle_debug(pr->handle,
1127  					"Throttling Control unsupported on CPU %d\n", i);
1128  				continue;
1129  			}
1130  
1131  			arg.pr = match_pr;
1132  			arg.target_state = state;
1133  			arg.force = force;
1134  			ret = call_on_cpu(pr->id, acpi_processor_throttling_fn,
1135  					  &arg, direct);
1136  		}
1137  	}
1138  	/*
1139  	 * After the set_throttling is called, the
1140  	 * throttling notifier is called for every
1141  	 * affected cpu to update the T-states.
1142  	 * The notifier event is THROTTLING_POSTCHANGE
1143  	 */
1144  	for_each_cpu_and(i, cpu_online_mask, p_throttling->shared_cpu_map) {
1145  		t_state.cpu = i;
1146  		acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1147  							&t_state);
1148  	}
1149  
1150  	return ret;
1151  }
1152  
acpi_processor_set_throttling(struct acpi_processor * pr,int state,bool force)1153  int acpi_processor_set_throttling(struct acpi_processor *pr, int state,
1154  				  bool force)
1155  {
1156  	return __acpi_processor_set_throttling(pr, state, force, false);
1157  }
1158  
acpi_processor_get_throttling_info(struct acpi_processor * pr)1159  int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1160  {
1161  	int result = 0;
1162  	struct acpi_processor_throttling *pthrottling;
1163  
1164  	acpi_handle_debug(pr->handle,
1165  			  "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1166  			  pr->throttling.address,
1167  			  pr->throttling.duty_offset,
1168  			  pr->throttling.duty_width);
1169  
1170  	/*
1171  	 * Evaluate _PTC, _TSS and _TPC
1172  	 * They must all be present or none of them can be used.
1173  	 */
1174  	if (acpi_processor_get_throttling_control(pr) ||
1175  		acpi_processor_get_throttling_states(pr) ||
1176  		acpi_processor_get_platform_limit(pr)) {
1177  		pr->throttling.acpi_processor_get_throttling =
1178  		    &acpi_processor_get_throttling_fadt;
1179  		pr->throttling.acpi_processor_set_throttling =
1180  		    &acpi_processor_set_throttling_fadt;
1181  		if (acpi_processor_get_fadt_info(pr))
1182  			return 0;
1183  	} else {
1184  		pr->throttling.acpi_processor_get_throttling =
1185  		    &acpi_processor_get_throttling_ptc;
1186  		pr->throttling.acpi_processor_set_throttling =
1187  		    &acpi_processor_set_throttling_ptc;
1188  	}
1189  
1190  	/*
1191  	 * If TSD package for one CPU can't be parsed successfully, it means
1192  	 * that this CPU will have no coordination with other CPUs.
1193  	 */
1194  	if (acpi_processor_get_tsd(pr)) {
1195  		pthrottling = &pr->throttling;
1196  		pthrottling->tsd_valid_flag = 0;
1197  		cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1198  		pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1199  	}
1200  
1201  	/*
1202  	 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1203  	 * This shouldn't be an issue as few (if any) mobile systems ever
1204  	 * used this part.
1205  	 */
1206  	if (errata.piix4.throttle) {
1207  		acpi_handle_debug(pr->handle,
1208  				  "Throttling not supported on PIIX4 A- or B-step\n");
1209  		return 0;
1210  	}
1211  
1212  	acpi_handle_debug(pr->handle, "Found %d throttling states\n",
1213  			  pr->throttling.state_count);
1214  
1215  	pr->flags.throttling = 1;
1216  
1217  	/*
1218  	 * Disable throttling (if enabled).  We'll let subsequent policy (e.g.
1219  	 * thermal) decide to lower performance if it so chooses, but for now
1220  	 * we'll crank up the speed.
1221  	 */
1222  
1223  	result = acpi_processor_get_throttling(pr);
1224  	if (result)
1225  		goto end;
1226  
1227  	if (pr->throttling.state) {
1228  		acpi_handle_debug(pr->handle,
1229  				  "Disabling throttling (was T%d)\n",
1230  				  pr->throttling.state);
1231  		result = acpi_processor_set_throttling(pr, 0, false);
1232  		if (result)
1233  			goto end;
1234  	}
1235  
1236  end:
1237  	if (result)
1238  		pr->flags.throttling = 0;
1239  
1240  	return result;
1241  }
1242  
1243