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v3.1
  1/*
  2 * acpi-cpufreq.c - ACPI Processor P-States Driver
  3 *
  4 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
  5 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
  6 *  Copyright (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
  7 *  Copyright (C) 2006       Denis Sadykov <denis.m.sadykov@intel.com>
  8 *
  9 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 10 *
 11 *  This program is free software; you can redistribute it and/or modify
 12 *  it under the terms of the GNU General Public License as published by
 13 *  the Free Software Foundation; either version 2 of the License, or (at
 14 *  your option) any later version.
 15 *
 16 *  This program is distributed in the hope that it will be useful, but
 17 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 18 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 19 *  General Public License for more details.
 20 *
 21 *  You should have received a copy of the GNU General Public License along
 22 *  with this program; if not, write to the Free Software Foundation, Inc.,
 23 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 24 *
 25 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 26 */
 27
 
 
 28#include <linux/kernel.h>
 29#include <linux/module.h>
 30#include <linux/init.h>
 31#include <linux/smp.h>
 32#include <linux/sched.h>
 33#include <linux/cpufreq.h>
 34#include <linux/compiler.h>
 35#include <linux/dmi.h>
 36#include <linux/slab.h>
 37
 38#include <linux/acpi.h>
 39#include <linux/io.h>
 40#include <linux/delay.h>
 41#include <linux/uaccess.h>
 42
 43#include <acpi/processor.h>
 44
 45#include <asm/msr.h>
 46#include <asm/processor.h>
 47#include <asm/cpufeature.h>
 48#include "mperf.h"
 49
 50MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
 51MODULE_DESCRIPTION("ACPI Processor P-States Driver");
 52MODULE_LICENSE("GPL");
 53
 54enum {
 55	UNDEFINED_CAPABLE = 0,
 56	SYSTEM_INTEL_MSR_CAPABLE,
 
 57	SYSTEM_IO_CAPABLE,
 58};
 59
 60#define INTEL_MSR_RANGE		(0xffff)
 
 
 
 61
 62struct acpi_cpufreq_data {
 63	struct acpi_processor_performance *acpi_data;
 64	struct cpufreq_frequency_table *freq_table;
 65	unsigned int resume;
 66	unsigned int cpu_feature;
 
 
 
 
 67};
 68
 69static DEFINE_PER_CPU(struct acpi_cpufreq_data *, acfreq_data);
 70
 71/* acpi_perf_data is a pointer to percpu data. */
 72static struct acpi_processor_performance __percpu *acpi_perf_data;
 73
 
 
 
 
 
 74static struct cpufreq_driver acpi_cpufreq_driver;
 75
 76static unsigned int acpi_pstate_strict;
 77
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 78static int check_est_cpu(unsigned int cpuid)
 79{
 80	struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 81
 82	return cpu_has(cpu, X86_FEATURE_EST);
 83}
 84
 85static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
 
 
 
 
 
 
 
 86{
 
 87	struct acpi_processor_performance *perf;
 88	int i;
 89
 90	perf = data->acpi_data;
 91
 92	for (i = 0; i < perf->state_count; i++) {
 93		if (value == perf->states[i].status)
 94			return data->freq_table[i].frequency;
 95	}
 96	return 0;
 97}
 98
 99static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
100{
101	int i;
 
102	struct acpi_processor_performance *perf;
103
104	msr &= INTEL_MSR_RANGE;
105	perf = data->acpi_data;
 
 
106
107	for (i = 0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
108		if (msr == perf->states[data->freq_table[i].index].status)
109			return data->freq_table[i].frequency;
110	}
111	return data->freq_table[0].frequency;
 
112}
113
114static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
115{
 
 
116	switch (data->cpu_feature) {
117	case SYSTEM_INTEL_MSR_CAPABLE:
118		return extract_msr(val, data);
 
119	case SYSTEM_IO_CAPABLE:
120		return extract_io(val, data);
121	default:
122		return 0;
123	}
124}
125
126struct msr_addr {
127	u32 reg;
128};
129
130struct io_addr {
131	u16 port;
132	u8 bit_width;
133};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
134
135struct drv_cmd {
136	unsigned int type;
137	const struct cpumask *mask;
138	union {
139		struct msr_addr msr;
140		struct io_addr io;
141	} addr;
142	u32 val;
 
 
 
 
143};
144
145/* Called via smp_call_function_single(), on the target CPU */
146static void do_drv_read(void *_cmd)
147{
148	struct drv_cmd *cmd = _cmd;
149	u32 h;
150
151	switch (cmd->type) {
152	case SYSTEM_INTEL_MSR_CAPABLE:
153		rdmsr(cmd->addr.msr.reg, cmd->val, h);
154		break;
155	case SYSTEM_IO_CAPABLE:
156		acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
157				&cmd->val,
158				(u32)cmd->addr.io.bit_width);
159		break;
160	default:
161		break;
162	}
163}
164
165/* Called via smp_call_function_many(), on the target CPUs */
166static void do_drv_write(void *_cmd)
167{
168	struct drv_cmd *cmd = _cmd;
169	u32 lo, hi;
 
 
 
 
170
171	switch (cmd->type) {
172	case SYSTEM_INTEL_MSR_CAPABLE:
173		rdmsr(cmd->addr.msr.reg, lo, hi);
174		lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
175		wrmsr(cmd->addr.msr.reg, lo, hi);
176		break;
177	case SYSTEM_IO_CAPABLE:
178		acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
179				cmd->val,
180				(u32)cmd->addr.io.bit_width);
181		break;
182	default:
183		break;
184	}
185}
186
187static void drv_read(struct drv_cmd *cmd)
 
188{
189	int err;
190	cmd->val = 0;
191
192	err = smp_call_function_any(cmd->mask, do_drv_read, cmd, 1);
193	WARN_ON_ONCE(err);	/* smp_call_function_any() was buggy? */
194}
195
196static void drv_write(struct drv_cmd *cmd)
 
197{
 
 
 
 
 
 
198	int this_cpu;
199
200	this_cpu = get_cpu();
201	if (cpumask_test_cpu(this_cpu, cmd->mask))
202		do_drv_write(cmd);
203	smp_call_function_many(cmd->mask, do_drv_write, cmd, 1);
 
204	put_cpu();
205}
206
207static u32 get_cur_val(const struct cpumask *mask)
208{
209	struct acpi_processor_performance *perf;
210	struct drv_cmd cmd;
211
212	if (unlikely(cpumask_empty(mask)))
213		return 0;
214
215	switch (per_cpu(acfreq_data, cpumask_first(mask))->cpu_feature) {
216	case SYSTEM_INTEL_MSR_CAPABLE:
217		cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
218		cmd.addr.msr.reg = MSR_IA32_PERF_STATUS;
219		break;
220	case SYSTEM_IO_CAPABLE:
221		cmd.type = SYSTEM_IO_CAPABLE;
222		perf = per_cpu(acfreq_data, cpumask_first(mask))->acpi_data;
223		cmd.addr.io.port = perf->control_register.address;
224		cmd.addr.io.bit_width = perf->control_register.bit_width;
225		break;
226	default:
227		return 0;
228	}
229
230	cmd.mask = mask;
231	drv_read(&cmd);
232
233	pr_debug("get_cur_val = %u\n", cmd.val);
234
235	return cmd.val;
236}
237
238static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
239{
240	struct acpi_cpufreq_data *data = per_cpu(acfreq_data, cpu);
 
241	unsigned int freq;
242	unsigned int cached_freq;
243
244	pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
245
246	if (unlikely(data == NULL ||
247		     data->acpi_data == NULL || data->freq_table == NULL)) {
248		return 0;
249	}
250
251	cached_freq = data->freq_table[data->acpi_data->state].frequency;
252	freq = extract_freq(get_cur_val(cpumask_of(cpu)), data);
 
 
 
 
253	if (freq != cached_freq) {
254		/*
255		 * The dreaded BIOS frequency change behind our back.
256		 * Force set the frequency on next target call.
257		 */
258		data->resume = 1;
259	}
260
261	pr_debug("cur freq = %u\n", freq);
262
263	return freq;
264}
265
266static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq,
267				struct acpi_cpufreq_data *data)
268{
 
269	unsigned int cur_freq;
270	unsigned int i;
271
272	for (i = 0; i < 100; i++) {
273		cur_freq = extract_freq(get_cur_val(mask), data);
274		if (cur_freq == freq)
275			return 1;
276		udelay(10);
277	}
278	return 0;
279}
280
281static int acpi_cpufreq_target(struct cpufreq_policy *policy,
282			       unsigned int target_freq, unsigned int relation)
283{
284	struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
285	struct acpi_processor_performance *perf;
286	struct cpufreq_freqs freqs;
287	struct drv_cmd cmd;
288	unsigned int next_state = 0; /* Index into freq_table */
289	unsigned int next_perf_state = 0; /* Index into perf table */
290	unsigned int i;
291	int result = 0;
292
293	pr_debug("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
294
295	if (unlikely(data == NULL ||
296	     data->acpi_data == NULL || data->freq_table == NULL)) {
297		return -ENODEV;
298	}
299
300	perf = data->acpi_data;
301	result = cpufreq_frequency_table_target(policy,
302						data->freq_table,
303						target_freq,
304						relation, &next_state);
305	if (unlikely(result)) {
306		result = -ENODEV;
307		goto out;
308	}
309
310	next_perf_state = data->freq_table[next_state].index;
311	if (perf->state == next_perf_state) {
312		if (unlikely(data->resume)) {
313			pr_debug("Called after resume, resetting to P%d\n",
314				next_perf_state);
315			data->resume = 0;
316		} else {
317			pr_debug("Already at target state (P%d)\n",
318				next_perf_state);
319			goto out;
320		}
321	}
322
323	switch (data->cpu_feature) {
324	case SYSTEM_INTEL_MSR_CAPABLE:
325		cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
326		cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
327		cmd.val = (u32) perf->states[next_perf_state].control;
328		break;
329	case SYSTEM_IO_CAPABLE:
330		cmd.type = SYSTEM_IO_CAPABLE;
331		cmd.addr.io.port = perf->control_register.address;
332		cmd.addr.io.bit_width = perf->control_register.bit_width;
333		cmd.val = (u32) perf->states[next_perf_state].control;
334		break;
335	default:
336		result = -ENODEV;
337		goto out;
338	}
339
340	/* cpufreq holds the hotplug lock, so we are safe from here on */
341	if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
342		cmd.mask = policy->cpus;
343	else
344		cmd.mask = cpumask_of(policy->cpu);
345
346	freqs.old = perf->states[perf->state].core_frequency * 1000;
347	freqs.new = data->freq_table[next_state].frequency;
348	for_each_cpu(i, policy->cpus) {
349		freqs.cpu = i;
350		cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
351	}
352
353	drv_write(&cmd);
354
355	if (acpi_pstate_strict) {
356		if (!check_freqs(cmd.mask, freqs.new, data)) {
 
357			pr_debug("acpi_cpufreq_target failed (%d)\n",
358				policy->cpu);
359			result = -EAGAIN;
360			goto out;
361		}
362	}
363
364	for_each_cpu(i, policy->cpus) {
365		freqs.cpu = i;
366		cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
367	}
368	perf->state = next_perf_state;
369
370out:
371	return result;
372}
373
374static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
 
375{
376	struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
 
 
 
377
378	pr_debug("acpi_cpufreq_verify\n");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
379
380	return cpufreq_frequency_table_verify(policy, data->freq_table);
 
 
 
381}
382
383static unsigned long
384acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
385{
386	struct acpi_processor_performance *perf = data->acpi_data;
387
 
388	if (cpu_khz) {
389		/* search the closest match to cpu_khz */
390		unsigned int i;
391		unsigned long freq;
392		unsigned long freqn = perf->states[0].core_frequency * 1000;
393
394		for (i = 0; i < (perf->state_count-1); i++) {
395			freq = freqn;
396			freqn = perf->states[i+1].core_frequency * 1000;
397			if ((2 * cpu_khz) > (freqn + freq)) {
398				perf->state = i;
399				return freq;
400			}
401		}
402		perf->state = perf->state_count-1;
403		return freqn;
404	} else {
405		/* assume CPU is at P0... */
406		perf->state = 0;
407		return perf->states[0].core_frequency * 1000;
408	}
409}
410
411static void free_acpi_perf_data(void)
412{
413	unsigned int i;
414
415	/* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
416	for_each_possible_cpu(i)
417		free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
418				 ->shared_cpu_map);
419	free_percpu(acpi_perf_data);
420}
421
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
422/*
423 * acpi_cpufreq_early_init - initialize ACPI P-States library
424 *
425 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
426 * in order to determine correct frequency and voltage pairings. We can
427 * do _PDC and _PSD and find out the processor dependency for the
428 * actual init that will happen later...
429 */
430static int __init acpi_cpufreq_early_init(void)
431{
432	unsigned int i;
433	pr_debug("acpi_cpufreq_early_init\n");
434
435	acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
436	if (!acpi_perf_data) {
437		pr_debug("Memory allocation error for acpi_perf_data.\n");
438		return -ENOMEM;
439	}
440	for_each_possible_cpu(i) {
441		if (!zalloc_cpumask_var_node(
442			&per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
443			GFP_KERNEL, cpu_to_node(i))) {
444
445			/* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
446			free_acpi_perf_data();
447			return -ENOMEM;
448		}
449	}
450
451	/* Do initialization in ACPI core */
452	acpi_processor_preregister_performance(acpi_perf_data);
453	return 0;
454}
455
456#ifdef CONFIG_SMP
457/*
458 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
459 * or do it in BIOS firmware and won't inform about it to OS. If not
460 * detected, this has a side effect of making CPU run at a different speed
461 * than OS intended it to run at. Detect it and handle it cleanly.
462 */
463static int bios_with_sw_any_bug;
464
465static int sw_any_bug_found(const struct dmi_system_id *d)
466{
467	bios_with_sw_any_bug = 1;
468	return 0;
469}
470
471static const struct dmi_system_id sw_any_bug_dmi_table[] = {
472	{
473		.callback = sw_any_bug_found,
474		.ident = "Supermicro Server X6DLP",
475		.matches = {
476			DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
477			DMI_MATCH(DMI_BIOS_VERSION, "080010"),
478			DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
479		},
480	},
481	{ }
482};
483
484static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
485{
486	/* Intel Xeon Processor 7100 Series Specification Update
487	 * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
488	 * AL30: A Machine Check Exception (MCE) Occurring during an
489	 * Enhanced Intel SpeedStep Technology Ratio Change May Cause
490	 * Both Processor Cores to Lock Up. */
491	if (c->x86_vendor == X86_VENDOR_INTEL) {
492		if ((c->x86 == 15) &&
493		    (c->x86_model == 6) &&
494		    (c->x86_mask == 8)) {
495			printk(KERN_INFO "acpi-cpufreq: Intel(R) "
496			    "Xeon(R) 7100 Errata AL30, processors may "
497			    "lock up on frequency changes: disabling "
498			    "acpi-cpufreq.\n");
499			return -ENODEV;
500		    }
501		}
502	return 0;
503}
504#endif
505
506static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
507{
508	unsigned int i;
509	unsigned int valid_states = 0;
510	unsigned int cpu = policy->cpu;
511	struct acpi_cpufreq_data *data;
512	unsigned int result = 0;
513	struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
514	struct acpi_processor_performance *perf;
 
515#ifdef CONFIG_SMP
516	static int blacklisted;
517#endif
518
519	pr_debug("acpi_cpufreq_cpu_init\n");
520
521#ifdef CONFIG_SMP
522	if (blacklisted)
523		return blacklisted;
524	blacklisted = acpi_cpufreq_blacklist(c);
525	if (blacklisted)
526		return blacklisted;
527#endif
528
529	data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
530	if (!data)
531		return -ENOMEM;
532
533	data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu);
534	per_cpu(acfreq_data, cpu) = data;
 
 
 
 
 
 
535
536	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
537		acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
538
539	result = acpi_processor_register_performance(data->acpi_data, cpu);
540	if (result)
541		goto err_free;
542
543	perf = data->acpi_data;
544	policy->shared_type = perf->shared_type;
545
546	/*
547	 * Will let policy->cpus know about dependency only when software
548	 * coordination is required.
549	 */
550	if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
551	    policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
552		cpumask_copy(policy->cpus, perf->shared_cpu_map);
553	}
554	cpumask_copy(policy->related_cpus, perf->shared_cpu_map);
555
556#ifdef CONFIG_SMP
557	dmi_check_system(sw_any_bug_dmi_table);
558	if (bios_with_sw_any_bug && cpumask_weight(policy->cpus) == 1) {
559		policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
560		cpumask_copy(policy->cpus, cpu_core_mask(cpu));
 
 
 
 
 
 
 
 
 
561	}
562#endif
563
564	/* capability check */
565	if (perf->state_count <= 1) {
566		pr_debug("No P-States\n");
567		result = -ENODEV;
568		goto err_unreg;
569	}
570
571	if (perf->control_register.space_id != perf->status_register.space_id) {
572		result = -ENODEV;
573		goto err_unreg;
574	}
575
576	switch (perf->control_register.space_id) {
577	case ACPI_ADR_SPACE_SYSTEM_IO:
 
 
 
 
 
 
578		pr_debug("SYSTEM IO addr space\n");
579		data->cpu_feature = SYSTEM_IO_CAPABLE;
 
 
580		break;
581	case ACPI_ADR_SPACE_FIXED_HARDWARE:
582		pr_debug("HARDWARE addr space\n");
583		if (!check_est_cpu(cpu)) {
584			result = -ENODEV;
585			goto err_unreg;
 
 
586		}
587		data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
588		break;
 
 
 
 
 
 
589	default:
590		pr_debug("Unknown addr space %d\n",
591			(u32) (perf->control_register.space_id));
592		result = -ENODEV;
593		goto err_unreg;
594	}
595
596	data->freq_table = kmalloc(sizeof(struct cpufreq_frequency_table) *
597		    (perf->state_count+1), GFP_KERNEL);
598	if (!data->freq_table) {
599		result = -ENOMEM;
600		goto err_unreg;
601	}
602
603	/* detect transition latency */
604	policy->cpuinfo.transition_latency = 0;
605	for (i = 0; i < perf->state_count; i++) {
606		if ((perf->states[i].transition_latency * 1000) >
607		    policy->cpuinfo.transition_latency)
608			policy->cpuinfo.transition_latency =
609			    perf->states[i].transition_latency * 1000;
610	}
611
612	/* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
613	if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
614	    policy->cpuinfo.transition_latency > 20 * 1000) {
615		policy->cpuinfo.transition_latency = 20 * 1000;
616		printk_once(KERN_INFO
617			    "P-state transition latency capped at 20 uS\n");
618	}
619
620	/* table init */
621	for (i = 0; i < perf->state_count; i++) {
622		if (i > 0 && perf->states[i].core_frequency >=
623		    data->freq_table[valid_states-1].frequency / 1000)
624			continue;
625
626		data->freq_table[valid_states].index = i;
627		data->freq_table[valid_states].frequency =
628		    perf->states[i].core_frequency * 1000;
629		valid_states++;
630	}
631	data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
632	perf->state = 0;
633
634	result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
635	if (result)
636		goto err_freqfree;
637
638	if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
639		printk(KERN_WARNING FW_WARN "P-state 0 is not max freq\n");
640
641	switch (perf->control_register.space_id) {
642	case ACPI_ADR_SPACE_SYSTEM_IO:
643		/* Current speed is unknown and not detectable by IO port */
 
 
 
 
 
644		policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
645		break;
646	case ACPI_ADR_SPACE_FIXED_HARDWARE:
647		acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
648		policy->cur = get_cur_freq_on_cpu(cpu);
649		break;
650	default:
651		break;
652	}
653
654	/* notify BIOS that we exist */
655	acpi_processor_notify_smm(THIS_MODULE);
656
657	/* Check for APERF/MPERF support in hardware */
658	if (boot_cpu_has(X86_FEATURE_APERFMPERF))
659		acpi_cpufreq_driver.getavg = cpufreq_get_measured_perf;
660
661	pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
662	for (i = 0; i < perf->state_count; i++)
663		pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
664			(i == perf->state ? '*' : ' '), i,
665			(u32) perf->states[i].core_frequency,
666			(u32) perf->states[i].power,
667			(u32) perf->states[i].transition_latency);
668
669	cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
670
671	/*
672	 * the first call to ->target() should result in us actually
673	 * writing something to the appropriate registers.
674	 */
675	data->resume = 1;
676
 
 
 
677	return result;
678
679err_freqfree:
680	kfree(data->freq_table);
681err_unreg:
682	acpi_processor_unregister_performance(perf, cpu);
 
 
683err_free:
684	kfree(data);
685	per_cpu(acfreq_data, cpu) = NULL;
686
687	return result;
688}
689
690static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
691{
692	struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
693
694	pr_debug("acpi_cpufreq_cpu_exit\n");
695
696	if (data) {
697		cpufreq_frequency_table_put_attr(policy->cpu);
698		per_cpu(acfreq_data, policy->cpu) = NULL;
699		acpi_processor_unregister_performance(data->acpi_data,
700						      policy->cpu);
701		kfree(data->freq_table);
702		kfree(data);
703	}
704
705	return 0;
706}
707
708static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
709{
710	struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
711
712	pr_debug("acpi_cpufreq_resume\n");
713
714	data->resume = 1;
715
716	return 0;
717}
718
719static struct freq_attr *acpi_cpufreq_attr[] = {
720	&cpufreq_freq_attr_scaling_available_freqs,
 
 
 
 
721	NULL,
722};
723
724static struct cpufreq_driver acpi_cpufreq_driver = {
725	.verify		= acpi_cpufreq_verify,
726	.target		= acpi_cpufreq_target,
 
727	.bios_limit	= acpi_processor_get_bios_limit,
728	.init		= acpi_cpufreq_cpu_init,
729	.exit		= acpi_cpufreq_cpu_exit,
730	.resume		= acpi_cpufreq_resume,
731	.name		= "acpi-cpufreq",
732	.owner		= THIS_MODULE,
733	.attr		= acpi_cpufreq_attr,
734};
735
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
736static int __init acpi_cpufreq_init(void)
737{
738	int ret;
739
740	if (acpi_disabled)
741		return 0;
 
 
 
 
742
743	pr_debug("acpi_cpufreq_init\n");
744
745	ret = acpi_cpufreq_early_init();
746	if (ret)
747		return ret;
748
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
749	ret = cpufreq_register_driver(&acpi_cpufreq_driver);
750	if (ret)
751		free_acpi_perf_data();
752
 
753	return ret;
754}
755
756static void __exit acpi_cpufreq_exit(void)
757{
758	pr_debug("acpi_cpufreq_exit\n");
759
 
 
760	cpufreq_unregister_driver(&acpi_cpufreq_driver);
761
762	free_acpi_perf_data();
763}
764
765module_param(acpi_pstate_strict, uint, 0644);
766MODULE_PARM_DESC(acpi_pstate_strict,
767	"value 0 or non-zero. non-zero -> strict ACPI checks are "
768	"performed during frequency changes.");
769
770late_initcall(acpi_cpufreq_init);
771module_exit(acpi_cpufreq_exit);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
772
773MODULE_ALIAS("acpi");
v4.10.11
   1/*
   2 * acpi-cpufreq.c - ACPI Processor P-States Driver
   3 *
   4 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   5 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6 *  Copyright (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
   7 *  Copyright (C) 2006       Denis Sadykov <denis.m.sadykov@intel.com>
   8 *
   9 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  10 *
  11 *  This program is free software; you can redistribute it and/or modify
  12 *  it under the terms of the GNU General Public License as published by
  13 *  the Free Software Foundation; either version 2 of the License, or (at
  14 *  your option) any later version.
  15 *
  16 *  This program is distributed in the hope that it will be useful, but
  17 *  WITHOUT ANY WARRANTY; without even the implied warranty of
  18 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19 *  General Public License for more details.
  20 *
  21 *  You should have received a copy of the GNU General Public License along
  22 *  with this program; if not, write to the Free Software Foundation, Inc.,
  23 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  24 *
  25 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  26 */
  27
  28#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  29
  30#include <linux/kernel.h>
  31#include <linux/module.h>
  32#include <linux/init.h>
  33#include <linux/smp.h>
  34#include <linux/sched.h>
  35#include <linux/cpufreq.h>
  36#include <linux/compiler.h>
  37#include <linux/dmi.h>
  38#include <linux/slab.h>
  39
  40#include <linux/acpi.h>
  41#include <linux/io.h>
  42#include <linux/delay.h>
  43#include <linux/uaccess.h>
  44
  45#include <acpi/processor.h>
  46
  47#include <asm/msr.h>
  48#include <asm/processor.h>
  49#include <asm/cpufeature.h>
 
  50
  51MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
  52MODULE_DESCRIPTION("ACPI Processor P-States Driver");
  53MODULE_LICENSE("GPL");
  54
  55enum {
  56	UNDEFINED_CAPABLE = 0,
  57	SYSTEM_INTEL_MSR_CAPABLE,
  58	SYSTEM_AMD_MSR_CAPABLE,
  59	SYSTEM_IO_CAPABLE,
  60};
  61
  62#define INTEL_MSR_RANGE		(0xffff)
  63#define AMD_MSR_RANGE		(0x7)
  64
  65#define MSR_K7_HWCR_CPB_DIS	(1ULL << 25)
  66
  67struct acpi_cpufreq_data {
 
 
  68	unsigned int resume;
  69	unsigned int cpu_feature;
  70	unsigned int acpi_perf_cpu;
  71	cpumask_var_t freqdomain_cpus;
  72	void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);
  73	u32 (*cpu_freq_read)(struct acpi_pct_register *reg);
  74};
  75
 
 
  76/* acpi_perf_data is a pointer to percpu data. */
  77static struct acpi_processor_performance __percpu *acpi_perf_data;
  78
  79static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
  80{
  81	return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
  82}
  83
  84static struct cpufreq_driver acpi_cpufreq_driver;
  85
  86static unsigned int acpi_pstate_strict;
  87
  88static bool boost_state(unsigned int cpu)
  89{
  90	u32 lo, hi;
  91	u64 msr;
  92
  93	switch (boot_cpu_data.x86_vendor) {
  94	case X86_VENDOR_INTEL:
  95		rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
  96		msr = lo | ((u64)hi << 32);
  97		return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
  98	case X86_VENDOR_AMD:
  99		rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
 100		msr = lo | ((u64)hi << 32);
 101		return !(msr & MSR_K7_HWCR_CPB_DIS);
 102	}
 103	return false;
 104}
 105
 106static int boost_set_msr(bool enable)
 107{
 108	u32 msr_addr;
 109	u64 msr_mask, val;
 110
 111	switch (boot_cpu_data.x86_vendor) {
 112	case X86_VENDOR_INTEL:
 113		msr_addr = MSR_IA32_MISC_ENABLE;
 114		msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
 115		break;
 116	case X86_VENDOR_AMD:
 117		msr_addr = MSR_K7_HWCR;
 118		msr_mask = MSR_K7_HWCR_CPB_DIS;
 119		break;
 120	default:
 121		return -EINVAL;
 122	}
 123
 124	rdmsrl(msr_addr, val);
 125
 126	if (enable)
 127		val &= ~msr_mask;
 128	else
 129		val |= msr_mask;
 130
 131	wrmsrl(msr_addr, val);
 132	return 0;
 133}
 134
 135static void boost_set_msr_each(void *p_en)
 136{
 137	bool enable = (bool) p_en;
 138
 139	boost_set_msr(enable);
 140}
 141
 142static int set_boost(int val)
 143{
 144	get_online_cpus();
 145	on_each_cpu(boost_set_msr_each, (void *)(long)val, 1);
 146	put_online_cpus();
 147	pr_debug("Core Boosting %sabled.\n", val ? "en" : "dis");
 148
 149	return 0;
 150}
 151
 152static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
 153{
 154	struct acpi_cpufreq_data *data = policy->driver_data;
 155
 156	if (unlikely(!data))
 157		return -ENODEV;
 158
 159	return cpufreq_show_cpus(data->freqdomain_cpus, buf);
 160}
 161
 162cpufreq_freq_attr_ro(freqdomain_cpus);
 163
 164#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 165static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
 166			 size_t count)
 167{
 168	int ret;
 169	unsigned int val = 0;
 170
 171	if (!acpi_cpufreq_driver.set_boost)
 172		return -EINVAL;
 173
 174	ret = kstrtouint(buf, 10, &val);
 175	if (ret || val > 1)
 176		return -EINVAL;
 177
 178	set_boost(val);
 179
 180	return count;
 181}
 182
 183static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
 184{
 185	return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
 186}
 187
 188cpufreq_freq_attr_rw(cpb);
 189#endif
 190
 191static int check_est_cpu(unsigned int cpuid)
 192{
 193	struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 194
 195	return cpu_has(cpu, X86_FEATURE_EST);
 196}
 197
 198static int check_amd_hwpstate_cpu(unsigned int cpuid)
 199{
 200	struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 201
 202	return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
 203}
 204
 205static unsigned extract_io(struct cpufreq_policy *policy, u32 value)
 206{
 207	struct acpi_cpufreq_data *data = policy->driver_data;
 208	struct acpi_processor_performance *perf;
 209	int i;
 210
 211	perf = to_perf_data(data);
 212
 213	for (i = 0; i < perf->state_count; i++) {
 214		if (value == perf->states[i].status)
 215			return policy->freq_table[i].frequency;
 216	}
 217	return 0;
 218}
 219
 220static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
 221{
 222	struct acpi_cpufreq_data *data = policy->driver_data;
 223	struct cpufreq_frequency_table *pos;
 224	struct acpi_processor_performance *perf;
 225
 226	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
 227		msr &= AMD_MSR_RANGE;
 228	else
 229		msr &= INTEL_MSR_RANGE;
 230
 231	perf = to_perf_data(data);
 232
 233	cpufreq_for_each_entry(pos, policy->freq_table)
 234		if (msr == perf->states[pos->driver_data].status)
 235			return pos->frequency;
 236	return policy->freq_table[0].frequency;
 237}
 238
 239static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
 240{
 241	struct acpi_cpufreq_data *data = policy->driver_data;
 242
 243	switch (data->cpu_feature) {
 244	case SYSTEM_INTEL_MSR_CAPABLE:
 245	case SYSTEM_AMD_MSR_CAPABLE:
 246		return extract_msr(policy, val);
 247	case SYSTEM_IO_CAPABLE:
 248		return extract_io(policy, val);
 249	default:
 250		return 0;
 251	}
 252}
 253
 254static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
 255{
 256	u32 val, dummy;
 257
 258	rdmsr(MSR_IA32_PERF_CTL, val, dummy);
 259	return val;
 260}
 261
 262static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
 263{
 264	u32 lo, hi;
 265
 266	rdmsr(MSR_IA32_PERF_CTL, lo, hi);
 267	lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
 268	wrmsr(MSR_IA32_PERF_CTL, lo, hi);
 269}
 270
 271static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
 272{
 273	u32 val, dummy;
 274
 275	rdmsr(MSR_AMD_PERF_CTL, val, dummy);
 276	return val;
 277}
 278
 279static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
 280{
 281	wrmsr(MSR_AMD_PERF_CTL, val, 0);
 282}
 283
 284static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
 285{
 286	u32 val;
 287
 288	acpi_os_read_port(reg->address, &val, reg->bit_width);
 289	return val;
 290}
 291
 292static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
 293{
 294	acpi_os_write_port(reg->address, val, reg->bit_width);
 295}
 296
 297struct drv_cmd {
 298	struct acpi_pct_register *reg;
 
 
 
 
 
 299	u32 val;
 300	union {
 301		void (*write)(struct acpi_pct_register *reg, u32 val);
 302		u32 (*read)(struct acpi_pct_register *reg);
 303	} func;
 304};
 305
 306/* Called via smp_call_function_single(), on the target CPU */
 307static void do_drv_read(void *_cmd)
 308{
 309	struct drv_cmd *cmd = _cmd;
 
 310
 311	cmd->val = cmd->func.read(cmd->reg);
 
 
 
 
 
 
 
 
 
 
 
 312}
 313
 314static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
 
 315{
 316	struct acpi_processor_performance *perf = to_perf_data(data);
 317	struct drv_cmd cmd = {
 318		.reg = &perf->control_register,
 319		.func.read = data->cpu_freq_read,
 320	};
 321	int err;
 322
 323	err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
 324	WARN_ON_ONCE(err);	/* smp_call_function_any() was buggy? */
 325	return cmd.val;
 
 
 
 
 
 
 
 
 
 
 
 326}
 327
 328/* Called via smp_call_function_many(), on the target CPUs */
 329static void do_drv_write(void *_cmd)
 330{
 331	struct drv_cmd *cmd = _cmd;
 
 332
 333	cmd->func.write(cmd->reg, cmd->val);
 
 334}
 335
 336static void drv_write(struct acpi_cpufreq_data *data,
 337		      const struct cpumask *mask, u32 val)
 338{
 339	struct acpi_processor_performance *perf = to_perf_data(data);
 340	struct drv_cmd cmd = {
 341		.reg = &perf->control_register,
 342		.val = val,
 343		.func.write = data->cpu_freq_write,
 344	};
 345	int this_cpu;
 346
 347	this_cpu = get_cpu();
 348	if (cpumask_test_cpu(this_cpu, mask))
 349		do_drv_write(&cmd);
 350
 351	smp_call_function_many(mask, do_drv_write, &cmd, 1);
 352	put_cpu();
 353}
 354
 355static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
 356{
 357	u32 val;
 
 358
 359	if (unlikely(cpumask_empty(mask)))
 360		return 0;
 361
 362	val = drv_read(data, mask);
 
 
 
 
 
 
 
 
 
 
 
 
 
 363
 364	pr_debug("get_cur_val = %u\n", val);
 
 365
 366	return val;
 
 
 367}
 368
 369static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 370{
 371	struct acpi_cpufreq_data *data;
 372	struct cpufreq_policy *policy;
 373	unsigned int freq;
 374	unsigned int cached_freq;
 375
 376	pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
 377
 378	policy = cpufreq_cpu_get_raw(cpu);
 379	if (unlikely(!policy))
 380		return 0;
 
 381
 382	data = policy->driver_data;
 383	if (unlikely(!data || !policy->freq_table))
 384		return 0;
 385
 386	cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;
 387	freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));
 388	if (freq != cached_freq) {
 389		/*
 390		 * The dreaded BIOS frequency change behind our back.
 391		 * Force set the frequency on next target call.
 392		 */
 393		data->resume = 1;
 394	}
 395
 396	pr_debug("cur freq = %u\n", freq);
 397
 398	return freq;
 399}
 400
 401static unsigned int check_freqs(struct cpufreq_policy *policy,
 402				const struct cpumask *mask, unsigned int freq)
 403{
 404	struct acpi_cpufreq_data *data = policy->driver_data;
 405	unsigned int cur_freq;
 406	unsigned int i;
 407
 408	for (i = 0; i < 100; i++) {
 409		cur_freq = extract_freq(policy, get_cur_val(mask, data));
 410		if (cur_freq == freq)
 411			return 1;
 412		udelay(10);
 413	}
 414	return 0;
 415}
 416
 417static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 418			       unsigned int index)
 419{
 420	struct acpi_cpufreq_data *data = policy->driver_data;
 421	struct acpi_processor_performance *perf;
 422	const struct cpumask *mask;
 
 
 423	unsigned int next_perf_state = 0; /* Index into perf table */
 
 424	int result = 0;
 425
 426	if (unlikely(!data)) {
 
 
 
 427		return -ENODEV;
 428	}
 429
 430	perf = to_perf_data(data);
 431	next_perf_state = policy->freq_table[index].driver_data;
 
 
 
 
 
 
 
 
 
 432	if (perf->state == next_perf_state) {
 433		if (unlikely(data->resume)) {
 434			pr_debug("Called after resume, resetting to P%d\n",
 435				next_perf_state);
 436			data->resume = 0;
 437		} else {
 438			pr_debug("Already at target state (P%d)\n",
 439				next_perf_state);
 440			return 0;
 441		}
 442	}
 443
 444	/*
 445	 * The core won't allow CPUs to go away until the governor has been
 446	 * stopped, so we can rely on the stability of policy->cpus.
 447	 */
 448	mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
 449		cpumask_of(policy->cpu) : policy->cpus;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 450
 451	drv_write(data, mask, perf->states[next_perf_state].control);
 452
 453	if (acpi_pstate_strict) {
 454		if (!check_freqs(policy, mask,
 455				 policy->freq_table[index].frequency)) {
 456			pr_debug("acpi_cpufreq_target failed (%d)\n",
 457				policy->cpu);
 458			result = -EAGAIN;
 
 459		}
 460	}
 461
 462	if (!result)
 463		perf->state = next_perf_state;
 
 
 
 464
 
 465	return result;
 466}
 467
 468unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
 469				      unsigned int target_freq)
 470{
 471	struct acpi_cpufreq_data *data = policy->driver_data;
 472	struct acpi_processor_performance *perf;
 473	struct cpufreq_frequency_table *entry;
 474	unsigned int next_perf_state, next_freq, index;
 475
 476	/*
 477	 * Find the closest frequency above target_freq.
 478	 */
 479	if (policy->cached_target_freq == target_freq)
 480		index = policy->cached_resolved_idx;
 481	else
 482		index = cpufreq_table_find_index_dl(policy, target_freq);
 483
 484	entry = &policy->freq_table[index];
 485	next_freq = entry->frequency;
 486	next_perf_state = entry->driver_data;
 487
 488	perf = to_perf_data(data);
 489	if (perf->state == next_perf_state) {
 490		if (unlikely(data->resume))
 491			data->resume = 0;
 492		else
 493			return next_freq;
 494	}
 495
 496	data->cpu_freq_write(&perf->control_register,
 497			     perf->states[next_perf_state].control);
 498	perf->state = next_perf_state;
 499	return next_freq;
 500}
 501
 502static unsigned long
 503acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 504{
 505	struct acpi_processor_performance *perf;
 506
 507	perf = to_perf_data(data);
 508	if (cpu_khz) {
 509		/* search the closest match to cpu_khz */
 510		unsigned int i;
 511		unsigned long freq;
 512		unsigned long freqn = perf->states[0].core_frequency * 1000;
 513
 514		for (i = 0; i < (perf->state_count-1); i++) {
 515			freq = freqn;
 516			freqn = perf->states[i+1].core_frequency * 1000;
 517			if ((2 * cpu_khz) > (freqn + freq)) {
 518				perf->state = i;
 519				return freq;
 520			}
 521		}
 522		perf->state = perf->state_count-1;
 523		return freqn;
 524	} else {
 525		/* assume CPU is at P0... */
 526		perf->state = 0;
 527		return perf->states[0].core_frequency * 1000;
 528	}
 529}
 530
 531static void free_acpi_perf_data(void)
 532{
 533	unsigned int i;
 534
 535	/* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
 536	for_each_possible_cpu(i)
 537		free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
 538				 ->shared_cpu_map);
 539	free_percpu(acpi_perf_data);
 540}
 541
 542static int cpufreq_boost_online(unsigned int cpu)
 543{
 544	/*
 545	 * On the CPU_UP path we simply keep the boost-disable flag
 546	 * in sync with the current global state.
 547	 */
 548	return boost_set_msr(acpi_cpufreq_driver.boost_enabled);
 549}
 550
 551static int cpufreq_boost_down_prep(unsigned int cpu)
 552{
 553	/*
 554	 * Clear the boost-disable bit on the CPU_DOWN path so that
 555	 * this cpu cannot block the remaining ones from boosting.
 556	 */
 557	return boost_set_msr(1);
 558}
 559
 560/*
 561 * acpi_cpufreq_early_init - initialize ACPI P-States library
 562 *
 563 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 564 * in order to determine correct frequency and voltage pairings. We can
 565 * do _PDC and _PSD and find out the processor dependency for the
 566 * actual init that will happen later...
 567 */
 568static int __init acpi_cpufreq_early_init(void)
 569{
 570	unsigned int i;
 571	pr_debug("acpi_cpufreq_early_init\n");
 572
 573	acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
 574	if (!acpi_perf_data) {
 575		pr_debug("Memory allocation error for acpi_perf_data.\n");
 576		return -ENOMEM;
 577	}
 578	for_each_possible_cpu(i) {
 579		if (!zalloc_cpumask_var_node(
 580			&per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
 581			GFP_KERNEL, cpu_to_node(i))) {
 582
 583			/* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
 584			free_acpi_perf_data();
 585			return -ENOMEM;
 586		}
 587	}
 588
 589	/* Do initialization in ACPI core */
 590	acpi_processor_preregister_performance(acpi_perf_data);
 591	return 0;
 592}
 593
 594#ifdef CONFIG_SMP
 595/*
 596 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 597 * or do it in BIOS firmware and won't inform about it to OS. If not
 598 * detected, this has a side effect of making CPU run at a different speed
 599 * than OS intended it to run at. Detect it and handle it cleanly.
 600 */
 601static int bios_with_sw_any_bug;
 602
 603static int sw_any_bug_found(const struct dmi_system_id *d)
 604{
 605	bios_with_sw_any_bug = 1;
 606	return 0;
 607}
 608
 609static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 610	{
 611		.callback = sw_any_bug_found,
 612		.ident = "Supermicro Server X6DLP",
 613		.matches = {
 614			DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 615			DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 616			DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 617		},
 618	},
 619	{ }
 620};
 621
 622static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
 623{
 624	/* Intel Xeon Processor 7100 Series Specification Update
 625	 * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
 626	 * AL30: A Machine Check Exception (MCE) Occurring during an
 627	 * Enhanced Intel SpeedStep Technology Ratio Change May Cause
 628	 * Both Processor Cores to Lock Up. */
 629	if (c->x86_vendor == X86_VENDOR_INTEL) {
 630		if ((c->x86 == 15) &&
 631		    (c->x86_model == 6) &&
 632		    (c->x86_mask == 8)) {
 633			pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");
 
 
 
 634			return -ENODEV;
 635		    }
 636		}
 637	return 0;
 638}
 639#endif
 640
 641static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 642{
 643	unsigned int i;
 644	unsigned int valid_states = 0;
 645	unsigned int cpu = policy->cpu;
 646	struct acpi_cpufreq_data *data;
 647	unsigned int result = 0;
 648	struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
 649	struct acpi_processor_performance *perf;
 650	struct cpufreq_frequency_table *freq_table;
 651#ifdef CONFIG_SMP
 652	static int blacklisted;
 653#endif
 654
 655	pr_debug("acpi_cpufreq_cpu_init\n");
 656
 657#ifdef CONFIG_SMP
 658	if (blacklisted)
 659		return blacklisted;
 660	blacklisted = acpi_cpufreq_blacklist(c);
 661	if (blacklisted)
 662		return blacklisted;
 663#endif
 664
 665	data = kzalloc(sizeof(*data), GFP_KERNEL);
 666	if (!data)
 667		return -ENOMEM;
 668
 669	if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
 670		result = -ENOMEM;
 671		goto err_free;
 672	}
 673
 674	perf = per_cpu_ptr(acpi_perf_data, cpu);
 675	data->acpi_perf_cpu = cpu;
 676	policy->driver_data = data;
 677
 678	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 679		acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 680
 681	result = acpi_processor_register_performance(perf, cpu);
 682	if (result)
 683		goto err_free_mask;
 684
 
 685	policy->shared_type = perf->shared_type;
 686
 687	/*
 688	 * Will let policy->cpus know about dependency only when software
 689	 * coordination is required.
 690	 */
 691	if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 692	    policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 693		cpumask_copy(policy->cpus, perf->shared_cpu_map);
 694	}
 695	cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
 696
 697#ifdef CONFIG_SMP
 698	dmi_check_system(sw_any_bug_dmi_table);
 699	if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
 700		policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 701		cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
 702	}
 703
 704	if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
 705		cpumask_clear(policy->cpus);
 706		cpumask_set_cpu(cpu, policy->cpus);
 707		cpumask_copy(data->freqdomain_cpus,
 708			     topology_sibling_cpumask(cpu));
 709		policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
 710		pr_info_once("overriding BIOS provided _PSD data\n");
 711	}
 712#endif
 713
 714	/* capability check */
 715	if (perf->state_count <= 1) {
 716		pr_debug("No P-States\n");
 717		result = -ENODEV;
 718		goto err_unreg;
 719	}
 720
 721	if (perf->control_register.space_id != perf->status_register.space_id) {
 722		result = -ENODEV;
 723		goto err_unreg;
 724	}
 725
 726	switch (perf->control_register.space_id) {
 727	case ACPI_ADR_SPACE_SYSTEM_IO:
 728		if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 729		    boot_cpu_data.x86 == 0xf) {
 730			pr_debug("AMD K8 systems must use native drivers.\n");
 731			result = -ENODEV;
 732			goto err_unreg;
 733		}
 734		pr_debug("SYSTEM IO addr space\n");
 735		data->cpu_feature = SYSTEM_IO_CAPABLE;
 736		data->cpu_freq_read = cpu_freq_read_io;
 737		data->cpu_freq_write = cpu_freq_write_io;
 738		break;
 739	case ACPI_ADR_SPACE_FIXED_HARDWARE:
 740		pr_debug("HARDWARE addr space\n");
 741		if (check_est_cpu(cpu)) {
 742			data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 743			data->cpu_freq_read = cpu_freq_read_intel;
 744			data->cpu_freq_write = cpu_freq_write_intel;
 745			break;
 746		}
 747		if (check_amd_hwpstate_cpu(cpu)) {
 748			data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
 749			data->cpu_freq_read = cpu_freq_read_amd;
 750			data->cpu_freq_write = cpu_freq_write_amd;
 751			break;
 752		}
 753		result = -ENODEV;
 754		goto err_unreg;
 755	default:
 756		pr_debug("Unknown addr space %d\n",
 757			(u32) (perf->control_register.space_id));
 758		result = -ENODEV;
 759		goto err_unreg;
 760	}
 761
 762	freq_table = kzalloc(sizeof(*freq_table) *
 763		    (perf->state_count+1), GFP_KERNEL);
 764	if (!freq_table) {
 765		result = -ENOMEM;
 766		goto err_unreg;
 767	}
 768
 769	/* detect transition latency */
 770	policy->cpuinfo.transition_latency = 0;
 771	for (i = 0; i < perf->state_count; i++) {
 772		if ((perf->states[i].transition_latency * 1000) >
 773		    policy->cpuinfo.transition_latency)
 774			policy->cpuinfo.transition_latency =
 775			    perf->states[i].transition_latency * 1000;
 776	}
 777
 778	/* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
 779	if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
 780	    policy->cpuinfo.transition_latency > 20 * 1000) {
 781		policy->cpuinfo.transition_latency = 20 * 1000;
 782		pr_info_once("P-state transition latency capped at 20 uS\n");
 
 783	}
 784
 785	/* table init */
 786	for (i = 0; i < perf->state_count; i++) {
 787		if (i > 0 && perf->states[i].core_frequency >=
 788		    freq_table[valid_states-1].frequency / 1000)
 789			continue;
 790
 791		freq_table[valid_states].driver_data = i;
 792		freq_table[valid_states].frequency =
 793		    perf->states[i].core_frequency * 1000;
 794		valid_states++;
 795	}
 796	freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 797	perf->state = 0;
 798
 799	result = cpufreq_table_validate_and_show(policy, freq_table);
 800	if (result)
 801		goto err_freqfree;
 802
 803	if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
 804		pr_warn(FW_WARN "P-state 0 is not max freq\n");
 805
 806	switch (perf->control_register.space_id) {
 807	case ACPI_ADR_SPACE_SYSTEM_IO:
 808		/*
 809		 * The core will not set policy->cur, because
 810		 * cpufreq_driver->get is NULL, so we need to set it here.
 811		 * However, we have to guess it, because the current speed is
 812		 * unknown and not detectable via IO ports.
 813		 */
 814		policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 815		break;
 816	case ACPI_ADR_SPACE_FIXED_HARDWARE:
 817		acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 
 818		break;
 819	default:
 820		break;
 821	}
 822
 823	/* notify BIOS that we exist */
 824	acpi_processor_notify_smm(THIS_MODULE);
 825
 
 
 
 
 826	pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
 827	for (i = 0; i < perf->state_count; i++)
 828		pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
 829			(i == perf->state ? '*' : ' '), i,
 830			(u32) perf->states[i].core_frequency,
 831			(u32) perf->states[i].power,
 832			(u32) perf->states[i].transition_latency);
 833
 
 
 834	/*
 835	 * the first call to ->target() should result in us actually
 836	 * writing something to the appropriate registers.
 837	 */
 838	data->resume = 1;
 839
 840	policy->fast_switch_possible = !acpi_pstate_strict &&
 841		!(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);
 842
 843	return result;
 844
 845err_freqfree:
 846	kfree(freq_table);
 847err_unreg:
 848	acpi_processor_unregister_performance(cpu);
 849err_free_mask:
 850	free_cpumask_var(data->freqdomain_cpus);
 851err_free:
 852	kfree(data);
 853	policy->driver_data = NULL;
 854
 855	return result;
 856}
 857
 858static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 859{
 860	struct acpi_cpufreq_data *data = policy->driver_data;
 861
 862	pr_debug("acpi_cpufreq_cpu_exit\n");
 863
 864	policy->fast_switch_possible = false;
 865	policy->driver_data = NULL;
 866	acpi_processor_unregister_performance(data->acpi_perf_cpu);
 867	free_cpumask_var(data->freqdomain_cpus);
 868	kfree(policy->freq_table);
 869	kfree(data);
 
 
 870
 871	return 0;
 872}
 873
 874static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 875{
 876	struct acpi_cpufreq_data *data = policy->driver_data;
 877
 878	pr_debug("acpi_cpufreq_resume\n");
 879
 880	data->resume = 1;
 881
 882	return 0;
 883}
 884
 885static struct freq_attr *acpi_cpufreq_attr[] = {
 886	&cpufreq_freq_attr_scaling_available_freqs,
 887	&freqdomain_cpus,
 888#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 889	&cpb,
 890#endif
 891	NULL,
 892};
 893
 894static struct cpufreq_driver acpi_cpufreq_driver = {
 895	.verify		= cpufreq_generic_frequency_table_verify,
 896	.target_index	= acpi_cpufreq_target,
 897	.fast_switch	= acpi_cpufreq_fast_switch,
 898	.bios_limit	= acpi_processor_get_bios_limit,
 899	.init		= acpi_cpufreq_cpu_init,
 900	.exit		= acpi_cpufreq_cpu_exit,
 901	.resume		= acpi_cpufreq_resume,
 902	.name		= "acpi-cpufreq",
 
 903	.attr		= acpi_cpufreq_attr,
 904};
 905
 906static enum cpuhp_state acpi_cpufreq_online;
 907
 908static void __init acpi_cpufreq_boost_init(void)
 909{
 910	int ret;
 911
 912	if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA)))
 913		return;
 914
 915	acpi_cpufreq_driver.set_boost = set_boost;
 916	acpi_cpufreq_driver.boost_enabled = boost_state(0);
 917
 918	/*
 919	 * This calls the online callback on all online cpu and forces all
 920	 * MSRs to the same value.
 921	 */
 922	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "cpufreq/acpi:online",
 923				cpufreq_boost_online, cpufreq_boost_down_prep);
 924	if (ret < 0) {
 925		pr_err("acpi_cpufreq: failed to register hotplug callbacks\n");
 926		return;
 927	}
 928	acpi_cpufreq_online = ret;
 929}
 930
 931static void acpi_cpufreq_boost_exit(void)
 932{
 933	if (acpi_cpufreq_online > 0)
 934		cpuhp_remove_state_nocalls(acpi_cpufreq_online);
 935}
 936
 937static int __init acpi_cpufreq_init(void)
 938{
 939	int ret;
 940
 941	if (acpi_disabled)
 942		return -ENODEV;
 943
 944	/* don't keep reloading if cpufreq_driver exists */
 945	if (cpufreq_get_current_driver())
 946		return -EEXIST;
 947
 948	pr_debug("acpi_cpufreq_init\n");
 949
 950	ret = acpi_cpufreq_early_init();
 951	if (ret)
 952		return ret;
 953
 954#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 955	/* this is a sysfs file with a strange name and an even stranger
 956	 * semantic - per CPU instantiation, but system global effect.
 957	 * Lets enable it only on AMD CPUs for compatibility reasons and
 958	 * only if configured. This is considered legacy code, which
 959	 * will probably be removed at some point in the future.
 960	 */
 961	if (!check_amd_hwpstate_cpu(0)) {
 962		struct freq_attr **attr;
 963
 964		pr_debug("CPB unsupported, do not expose it\n");
 965
 966		for (attr = acpi_cpufreq_attr; *attr; attr++)
 967			if (*attr == &cpb) {
 968				*attr = NULL;
 969				break;
 970			}
 971	}
 972#endif
 973	acpi_cpufreq_boost_init();
 974
 975	ret = cpufreq_register_driver(&acpi_cpufreq_driver);
 976	if (ret) {
 977		free_acpi_perf_data();
 978		acpi_cpufreq_boost_exit();
 979	}
 980	return ret;
 981}
 982
 983static void __exit acpi_cpufreq_exit(void)
 984{
 985	pr_debug("acpi_cpufreq_exit\n");
 986
 987	acpi_cpufreq_boost_exit();
 988
 989	cpufreq_unregister_driver(&acpi_cpufreq_driver);
 990
 991	free_acpi_perf_data();
 992}
 993
 994module_param(acpi_pstate_strict, uint, 0644);
 995MODULE_PARM_DESC(acpi_pstate_strict,
 996	"value 0 or non-zero. non-zero -> strict ACPI checks are "
 997	"performed during frequency changes.");
 998
 999late_initcall(acpi_cpufreq_init);
1000module_exit(acpi_cpufreq_exit);
1001
1002static const struct x86_cpu_id acpi_cpufreq_ids[] = {
1003	X86_FEATURE_MATCH(X86_FEATURE_ACPI),
1004	X86_FEATURE_MATCH(X86_FEATURE_HW_PSTATE),
1005	{}
1006};
1007MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1008
1009static const struct acpi_device_id processor_device_ids[] = {
1010	{ACPI_PROCESSOR_OBJECT_HID, },
1011	{ACPI_PROCESSOR_DEVICE_HID, },
1012	{},
1013};
1014MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1015
1016MODULE_ALIAS("acpi");