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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");
v3.15
   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
  49MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
  50MODULE_DESCRIPTION("ACPI Processor P-States Driver");
  51MODULE_LICENSE("GPL");
  52
  53#define PFX "acpi-cpufreq: "
  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	struct acpi_processor_performance *acpi_data;
  69	struct cpufreq_frequency_table *freq_table;
  70	unsigned int resume;
  71	unsigned int cpu_feature;
  72	cpumask_var_t freqdomain_cpus;
  73};
  74
  75static DEFINE_PER_CPU(struct acpi_cpufreq_data *, acfreq_data);
  76
  77/* acpi_perf_data is a pointer to percpu data. */
  78static struct acpi_processor_performance __percpu *acpi_perf_data;
  79
  80static struct cpufreq_driver acpi_cpufreq_driver;
  81
  82static unsigned int acpi_pstate_strict;
  83static struct msr __percpu *msrs;
  84
  85static bool boost_state(unsigned int cpu)
  86{
  87	u32 lo, hi;
  88	u64 msr;
  89
  90	switch (boot_cpu_data.x86_vendor) {
  91	case X86_VENDOR_INTEL:
  92		rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
  93		msr = lo | ((u64)hi << 32);
  94		return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
  95	case X86_VENDOR_AMD:
  96		rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
  97		msr = lo | ((u64)hi << 32);
  98		return !(msr & MSR_K7_HWCR_CPB_DIS);
  99	}
 100	return false;
 101}
 102
 103static void boost_set_msrs(bool enable, const struct cpumask *cpumask)
 104{
 105	u32 cpu;
 106	u32 msr_addr;
 107	u64 msr_mask;
 108
 109	switch (boot_cpu_data.x86_vendor) {
 110	case X86_VENDOR_INTEL:
 111		msr_addr = MSR_IA32_MISC_ENABLE;
 112		msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
 113		break;
 114	case X86_VENDOR_AMD:
 115		msr_addr = MSR_K7_HWCR;
 116		msr_mask = MSR_K7_HWCR_CPB_DIS;
 117		break;
 118	default:
 119		return;
 120	}
 121
 122	rdmsr_on_cpus(cpumask, msr_addr, msrs);
 123
 124	for_each_cpu(cpu, cpumask) {
 125		struct msr *reg = per_cpu_ptr(msrs, cpu);
 126		if (enable)
 127			reg->q &= ~msr_mask;
 128		else
 129			reg->q |= msr_mask;
 130	}
 131
 132	wrmsr_on_cpus(cpumask, msr_addr, msrs);
 133}
 134
 135static int _store_boost(int val)
 136{
 137	get_online_cpus();
 138	boost_set_msrs(val, cpu_online_mask);
 139	put_online_cpus();
 140	pr_debug("Core Boosting %sabled.\n", val ? "en" : "dis");
 141
 142	return 0;
 143}
 144
 145static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
 146{
 147	struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
 148
 149	return cpufreq_show_cpus(data->freqdomain_cpus, buf);
 150}
 151
 152cpufreq_freq_attr_ro(freqdomain_cpus);
 153
 154#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 155static ssize_t store_boost(const char *buf, size_t count)
 156{
 157	int ret;
 158	unsigned long val = 0;
 159
 160	if (!acpi_cpufreq_driver.boost_supported)
 161		return -EINVAL;
 162
 163	ret = kstrtoul(buf, 10, &val);
 164	if (ret || (val > 1))
 165		return -EINVAL;
 166
 167	_store_boost((int) val);
 168
 169	return count;
 170}
 171
 172static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
 173			 size_t count)
 174{
 175	return store_boost(buf, count);
 176}
 177
 178static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
 179{
 180	return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
 181}
 182
 183cpufreq_freq_attr_rw(cpb);
 184#endif
 185
 186static int check_est_cpu(unsigned int cpuid)
 187{
 188	struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 189
 190	return cpu_has(cpu, X86_FEATURE_EST);
 191}
 192
 193static int check_amd_hwpstate_cpu(unsigned int cpuid)
 194{
 195	struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 196
 197	return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
 198}
 199
 200static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
 201{
 202	struct acpi_processor_performance *perf;
 203	int i;
 204
 205	perf = data->acpi_data;
 206
 207	for (i = 0; i < perf->state_count; i++) {
 208		if (value == perf->states[i].status)
 209			return data->freq_table[i].frequency;
 210	}
 211	return 0;
 212}
 213
 214static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
 215{
 216	int i;
 217	struct acpi_processor_performance *perf;
 218
 219	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
 220		msr &= AMD_MSR_RANGE;
 221	else
 222		msr &= INTEL_MSR_RANGE;
 223
 224	perf = data->acpi_data;
 225
 226	for (i = 0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
 227		if (msr == perf->states[data->freq_table[i].driver_data].status)
 228			return data->freq_table[i].frequency;
 229	}
 230	return data->freq_table[0].frequency;
 231}
 232
 233static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
 234{
 235	switch (data->cpu_feature) {
 236	case SYSTEM_INTEL_MSR_CAPABLE:
 237	case SYSTEM_AMD_MSR_CAPABLE:
 238		return extract_msr(val, data);
 239	case SYSTEM_IO_CAPABLE:
 240		return extract_io(val, data);
 241	default:
 242		return 0;
 243	}
 244}
 245
 246struct msr_addr {
 247	u32 reg;
 248};
 249
 250struct io_addr {
 251	u16 port;
 252	u8 bit_width;
 253};
 254
 255struct drv_cmd {
 256	unsigned int type;
 257	const struct cpumask *mask;
 258	union {
 259		struct msr_addr msr;
 260		struct io_addr io;
 261	} addr;
 262	u32 val;
 263};
 264
 265/* Called via smp_call_function_single(), on the target CPU */
 266static void do_drv_read(void *_cmd)
 267{
 268	struct drv_cmd *cmd = _cmd;
 269	u32 h;
 270
 271	switch (cmd->type) {
 272	case SYSTEM_INTEL_MSR_CAPABLE:
 273	case SYSTEM_AMD_MSR_CAPABLE:
 274		rdmsr(cmd->addr.msr.reg, cmd->val, h);
 275		break;
 276	case SYSTEM_IO_CAPABLE:
 277		acpi_os_read_port((acpi_io_address)cmd->addr.io.port,
 278				&cmd->val,
 279				(u32)cmd->addr.io.bit_width);
 280		break;
 281	default:
 282		break;
 283	}
 284}
 285
 286/* Called via smp_call_function_many(), on the target CPUs */
 287static void do_drv_write(void *_cmd)
 288{
 289	struct drv_cmd *cmd = _cmd;
 290	u32 lo, hi;
 291
 292	switch (cmd->type) {
 293	case SYSTEM_INTEL_MSR_CAPABLE:
 294		rdmsr(cmd->addr.msr.reg, lo, hi);
 295		lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE);
 296		wrmsr(cmd->addr.msr.reg, lo, hi);
 297		break;
 298	case SYSTEM_AMD_MSR_CAPABLE:
 299		wrmsr(cmd->addr.msr.reg, cmd->val, 0);
 300		break;
 301	case SYSTEM_IO_CAPABLE:
 302		acpi_os_write_port((acpi_io_address)cmd->addr.io.port,
 303				cmd->val,
 304				(u32)cmd->addr.io.bit_width);
 305		break;
 306	default:
 307		break;
 308	}
 309}
 310
 311static void drv_read(struct drv_cmd *cmd)
 312{
 313	int err;
 314	cmd->val = 0;
 315
 316	err = smp_call_function_any(cmd->mask, do_drv_read, cmd, 1);
 317	WARN_ON_ONCE(err);	/* smp_call_function_any() was buggy? */
 318}
 319
 320static void drv_write(struct drv_cmd *cmd)
 321{
 322	int this_cpu;
 323
 324	this_cpu = get_cpu();
 325	if (cpumask_test_cpu(this_cpu, cmd->mask))
 326		do_drv_write(cmd);
 327	smp_call_function_many(cmd->mask, do_drv_write, cmd, 1);
 328	put_cpu();
 329}
 330
 331static u32 get_cur_val(const struct cpumask *mask)
 332{
 333	struct acpi_processor_performance *perf;
 334	struct drv_cmd cmd;
 335
 336	if (unlikely(cpumask_empty(mask)))
 337		return 0;
 338
 339	switch (per_cpu(acfreq_data, cpumask_first(mask))->cpu_feature) {
 340	case SYSTEM_INTEL_MSR_CAPABLE:
 341		cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
 342		cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
 343		break;
 344	case SYSTEM_AMD_MSR_CAPABLE:
 345		cmd.type = SYSTEM_AMD_MSR_CAPABLE;
 346		cmd.addr.msr.reg = MSR_AMD_PERF_CTL;
 347		break;
 348	case SYSTEM_IO_CAPABLE:
 349		cmd.type = SYSTEM_IO_CAPABLE;
 350		perf = per_cpu(acfreq_data, cpumask_first(mask))->acpi_data;
 351		cmd.addr.io.port = perf->control_register.address;
 352		cmd.addr.io.bit_width = perf->control_register.bit_width;
 353		break;
 354	default:
 355		return 0;
 356	}
 357
 358	cmd.mask = mask;
 359	drv_read(&cmd);
 360
 361	pr_debug("get_cur_val = %u\n", cmd.val);
 362
 363	return cmd.val;
 364}
 365
 366static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 367{
 368	struct acpi_cpufreq_data *data = per_cpu(acfreq_data, cpu);
 369	unsigned int freq;
 370	unsigned int cached_freq;
 371
 372	pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
 373
 374	if (unlikely(data == NULL ||
 375		     data->acpi_data == NULL || data->freq_table == NULL)) {
 376		return 0;
 377	}
 378
 379	cached_freq = data->freq_table[data->acpi_data->state].frequency;
 380	freq = extract_freq(get_cur_val(cpumask_of(cpu)), data);
 381	if (freq != cached_freq) {
 382		/*
 383		 * The dreaded BIOS frequency change behind our back.
 384		 * Force set the frequency on next target call.
 385		 */
 386		data->resume = 1;
 387	}
 388
 389	pr_debug("cur freq = %u\n", freq);
 390
 391	return freq;
 392}
 393
 394static unsigned int check_freqs(const struct cpumask *mask, unsigned int freq,
 395				struct acpi_cpufreq_data *data)
 396{
 397	unsigned int cur_freq;
 398	unsigned int i;
 399
 400	for (i = 0; i < 100; i++) {
 401		cur_freq = extract_freq(get_cur_val(mask), data);
 402		if (cur_freq == freq)
 403			return 1;
 404		udelay(10);
 405	}
 406	return 0;
 407}
 408
 409static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 410			       unsigned int index)
 411{
 412	struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
 413	struct acpi_processor_performance *perf;
 
 414	struct drv_cmd cmd;
 
 415	unsigned int next_perf_state = 0; /* Index into perf table */
 
 416	int result = 0;
 417
 
 
 418	if (unlikely(data == NULL ||
 419	     data->acpi_data == NULL || data->freq_table == NULL)) {
 420		return -ENODEV;
 421	}
 422
 423	perf = data->acpi_data;
 424	next_perf_state = data->freq_table[index].driver_data;
 
 
 
 
 
 
 
 
 
 425	if (perf->state == next_perf_state) {
 426		if (unlikely(data->resume)) {
 427			pr_debug("Called after resume, resetting to P%d\n",
 428				next_perf_state);
 429			data->resume = 0;
 430		} else {
 431			pr_debug("Already at target state (P%d)\n",
 432				next_perf_state);
 433			goto out;
 434		}
 435	}
 436
 437	switch (data->cpu_feature) {
 438	case SYSTEM_INTEL_MSR_CAPABLE:
 439		cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
 440		cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
 441		cmd.val = (u32) perf->states[next_perf_state].control;
 442		break;
 443	case SYSTEM_AMD_MSR_CAPABLE:
 444		cmd.type = SYSTEM_AMD_MSR_CAPABLE;
 445		cmd.addr.msr.reg = MSR_AMD_PERF_CTL;
 446		cmd.val = (u32) perf->states[next_perf_state].control;
 447		break;
 448	case SYSTEM_IO_CAPABLE:
 449		cmd.type = SYSTEM_IO_CAPABLE;
 450		cmd.addr.io.port = perf->control_register.address;
 451		cmd.addr.io.bit_width = perf->control_register.bit_width;
 452		cmd.val = (u32) perf->states[next_perf_state].control;
 453		break;
 454	default:
 455		result = -ENODEV;
 456		goto out;
 457	}
 458
 459	/* cpufreq holds the hotplug lock, so we are safe from here on */
 460	if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
 461		cmd.mask = policy->cpus;
 462	else
 463		cmd.mask = cpumask_of(policy->cpu);
 464
 
 
 
 
 
 
 
 465	drv_write(&cmd);
 466
 467	if (acpi_pstate_strict) {
 468		if (!check_freqs(cmd.mask, data->freq_table[index].frequency,
 469					data)) {
 470			pr_debug("acpi_cpufreq_target failed (%d)\n",
 471				policy->cpu);
 472			result = -EAGAIN;
 
 473		}
 474	}
 475
 476	if (!result)
 477		perf->state = next_perf_state;
 
 
 
 478
 479out:
 480	return result;
 481}
 482
 
 
 
 
 
 
 
 
 
 483static unsigned long
 484acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 485{
 486	struct acpi_processor_performance *perf = data->acpi_data;
 487
 488	if (cpu_khz) {
 489		/* search the closest match to cpu_khz */
 490		unsigned int i;
 491		unsigned long freq;
 492		unsigned long freqn = perf->states[0].core_frequency * 1000;
 493
 494		for (i = 0; i < (perf->state_count-1); i++) {
 495			freq = freqn;
 496			freqn = perf->states[i+1].core_frequency * 1000;
 497			if ((2 * cpu_khz) > (freqn + freq)) {
 498				perf->state = i;
 499				return freq;
 500			}
 501		}
 502		perf->state = perf->state_count-1;
 503		return freqn;
 504	} else {
 505		/* assume CPU is at P0... */
 506		perf->state = 0;
 507		return perf->states[0].core_frequency * 1000;
 508	}
 509}
 510
 511static void free_acpi_perf_data(void)
 512{
 513	unsigned int i;
 514
 515	/* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
 516	for_each_possible_cpu(i)
 517		free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
 518				 ->shared_cpu_map);
 519	free_percpu(acpi_perf_data);
 520}
 521
 522static int boost_notify(struct notifier_block *nb, unsigned long action,
 523		      void *hcpu)
 524{
 525	unsigned cpu = (long)hcpu;
 526	const struct cpumask *cpumask;
 527
 528	cpumask = get_cpu_mask(cpu);
 529
 530	/*
 531	 * Clear the boost-disable bit on the CPU_DOWN path so that
 532	 * this cpu cannot block the remaining ones from boosting. On
 533	 * the CPU_UP path we simply keep the boost-disable flag in
 534	 * sync with the current global state.
 535	 */
 536
 537	switch (action) {
 538	case CPU_UP_PREPARE:
 539	case CPU_UP_PREPARE_FROZEN:
 540		boost_set_msrs(acpi_cpufreq_driver.boost_enabled, cpumask);
 541		break;
 542
 543	case CPU_DOWN_PREPARE:
 544	case CPU_DOWN_PREPARE_FROZEN:
 545		boost_set_msrs(1, cpumask);
 546		break;
 547
 548	default:
 549		break;
 550	}
 551
 552	return NOTIFY_OK;
 553}
 554
 555
 556static struct notifier_block boost_nb = {
 557	.notifier_call          = boost_notify,
 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			printk(KERN_INFO "acpi-cpufreq: Intel(R) "
 634			    "Xeon(R) 7100 Errata AL30, processors may "
 635			    "lock up on frequency changes: disabling "
 636			    "acpi-cpufreq.\n");
 637			return -ENODEV;
 638		    }
 639		}
 640	return 0;
 641}
 642#endif
 643
 644static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 645{
 646	unsigned int i;
 647	unsigned int valid_states = 0;
 648	unsigned int cpu = policy->cpu;
 649	struct acpi_cpufreq_data *data;
 650	unsigned int result = 0;
 651	struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
 652	struct acpi_processor_performance *perf;
 653#ifdef CONFIG_SMP
 654	static int blacklisted;
 655#endif
 656
 657	pr_debug("acpi_cpufreq_cpu_init\n");
 658
 659#ifdef CONFIG_SMP
 660	if (blacklisted)
 661		return blacklisted;
 662	blacklisted = acpi_cpufreq_blacklist(c);
 663	if (blacklisted)
 664		return blacklisted;
 665#endif
 666
 667	data = kzalloc(sizeof(*data), GFP_KERNEL);
 668	if (!data)
 669		return -ENOMEM;
 670
 671	if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
 672		result = -ENOMEM;
 673		goto err_free;
 674	}
 675
 676	data->acpi_data = per_cpu_ptr(acpi_perf_data, cpu);
 677	per_cpu(acfreq_data, cpu) = data;
 678
 679	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 680		acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 681
 682	result = acpi_processor_register_performance(data->acpi_data, cpu);
 683	if (result)
 684		goto err_free_mask;
 685
 686	perf = data->acpi_data;
 687	policy->shared_type = perf->shared_type;
 688
 689	/*
 690	 * Will let policy->cpus know about dependency only when software
 691	 * coordination is required.
 692	 */
 693	if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 694	    policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 695		cpumask_copy(policy->cpus, perf->shared_cpu_map);
 696	}
 697	cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
 698
 699#ifdef CONFIG_SMP
 700	dmi_check_system(sw_any_bug_dmi_table);
 701	if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
 702		policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 703		cpumask_copy(policy->cpus, cpu_core_mask(cpu));
 704	}
 705
 706	if (check_amd_hwpstate_cpu(cpu) && !acpi_pstate_strict) {
 707		cpumask_clear(policy->cpus);
 708		cpumask_set_cpu(cpu, policy->cpus);
 709		cpumask_copy(data->freqdomain_cpus, cpu_sibling_mask(cpu));
 710		policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
 711		pr_info_once(PFX "overriding BIOS provided _PSD data\n");
 712	}
 713#endif
 714
 715	/* capability check */
 716	if (perf->state_count <= 1) {
 717		pr_debug("No P-States\n");
 718		result = -ENODEV;
 719		goto err_unreg;
 720	}
 721
 722	if (perf->control_register.space_id != perf->status_register.space_id) {
 723		result = -ENODEV;
 724		goto err_unreg;
 725	}
 726
 727	switch (perf->control_register.space_id) {
 728	case ACPI_ADR_SPACE_SYSTEM_IO:
 729		if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 730		    boot_cpu_data.x86 == 0xf) {
 731			pr_debug("AMD K8 systems must use native drivers.\n");
 732			result = -ENODEV;
 733			goto err_unreg;
 734		}
 735		pr_debug("SYSTEM IO addr space\n");
 736		data->cpu_feature = SYSTEM_IO_CAPABLE;
 737		break;
 738	case ACPI_ADR_SPACE_FIXED_HARDWARE:
 739		pr_debug("HARDWARE addr space\n");
 740		if (check_est_cpu(cpu)) {
 741			data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 742			break;
 743		}
 744		if (check_amd_hwpstate_cpu(cpu)) {
 745			data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
 746			break;
 747		}
 748		result = -ENODEV;
 749		goto err_unreg;
 750	default:
 751		pr_debug("Unknown addr space %d\n",
 752			(u32) (perf->control_register.space_id));
 753		result = -ENODEV;
 754		goto err_unreg;
 755	}
 756
 757	data->freq_table = kzalloc(sizeof(*data->freq_table) *
 758		    (perf->state_count+1), GFP_KERNEL);
 759	if (!data->freq_table) {
 760		result = -ENOMEM;
 761		goto err_unreg;
 762	}
 763
 764	/* detect transition latency */
 765	policy->cpuinfo.transition_latency = 0;
 766	for (i = 0; i < perf->state_count; i++) {
 767		if ((perf->states[i].transition_latency * 1000) >
 768		    policy->cpuinfo.transition_latency)
 769			policy->cpuinfo.transition_latency =
 770			    perf->states[i].transition_latency * 1000;
 771	}
 772
 773	/* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
 774	if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
 775	    policy->cpuinfo.transition_latency > 20 * 1000) {
 776		policy->cpuinfo.transition_latency = 20 * 1000;
 777		printk_once(KERN_INFO
 778			    "P-state transition latency capped at 20 uS\n");
 779	}
 780
 781	/* table init */
 782	for (i = 0; i < perf->state_count; i++) {
 783		if (i > 0 && perf->states[i].core_frequency >=
 784		    data->freq_table[valid_states-1].frequency / 1000)
 785			continue;
 786
 787		data->freq_table[valid_states].driver_data = i;
 788		data->freq_table[valid_states].frequency =
 789		    perf->states[i].core_frequency * 1000;
 790		valid_states++;
 791	}
 792	data->freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 793	perf->state = 0;
 794
 795	result = cpufreq_table_validate_and_show(policy, data->freq_table);
 796	if (result)
 797		goto err_freqfree;
 798
 799	if (perf->states[0].core_frequency * 1000 != policy->cpuinfo.max_freq)
 800		printk(KERN_WARNING FW_WARN "P-state 0 is not max freq\n");
 801
 802	switch (perf->control_register.space_id) {
 803	case ACPI_ADR_SPACE_SYSTEM_IO:
 804		/*
 805		 * The core will not set policy->cur, because
 806		 * cpufreq_driver->get is NULL, so we need to set it here.
 807		 * However, we have to guess it, because the current speed is
 808		 * unknown and not detectable via IO ports.
 809		 */
 810		policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 811		break;
 812	case ACPI_ADR_SPACE_FIXED_HARDWARE:
 813		acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 
 814		break;
 815	default:
 816		break;
 817	}
 818
 819	/* notify BIOS that we exist */
 820	acpi_processor_notify_smm(THIS_MODULE);
 821
 
 
 
 
 822	pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
 823	for (i = 0; i < perf->state_count; i++)
 824		pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
 825			(i == perf->state ? '*' : ' '), i,
 826			(u32) perf->states[i].core_frequency,
 827			(u32) perf->states[i].power,
 828			(u32) perf->states[i].transition_latency);
 829
 
 
 830	/*
 831	 * the first call to ->target() should result in us actually
 832	 * writing something to the appropriate registers.
 833	 */
 834	data->resume = 1;
 835
 836	return result;
 837
 838err_freqfree:
 839	kfree(data->freq_table);
 840err_unreg:
 841	acpi_processor_unregister_performance(perf, cpu);
 842err_free_mask:
 843	free_cpumask_var(data->freqdomain_cpus);
 844err_free:
 845	kfree(data);
 846	per_cpu(acfreq_data, cpu) = NULL;
 847
 848	return result;
 849}
 850
 851static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 852{
 853	struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
 854
 855	pr_debug("acpi_cpufreq_cpu_exit\n");
 856
 857	if (data) {
 
 858		per_cpu(acfreq_data, policy->cpu) = NULL;
 859		acpi_processor_unregister_performance(data->acpi_data,
 860						      policy->cpu);
 861		free_cpumask_var(data->freqdomain_cpus);
 862		kfree(data->freq_table);
 863		kfree(data);
 864	}
 865
 866	return 0;
 867}
 868
 869static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 870{
 871	struct acpi_cpufreq_data *data = per_cpu(acfreq_data, policy->cpu);
 872
 873	pr_debug("acpi_cpufreq_resume\n");
 874
 875	data->resume = 1;
 876
 877	return 0;
 878}
 879
 880static struct freq_attr *acpi_cpufreq_attr[] = {
 881	&cpufreq_freq_attr_scaling_available_freqs,
 882	&freqdomain_cpus,
 883	NULL,	/* this is a placeholder for cpb, do not remove */
 884	NULL,
 885};
 886
 887static struct cpufreq_driver acpi_cpufreq_driver = {
 888	.verify		= cpufreq_generic_frequency_table_verify,
 889	.target_index	= acpi_cpufreq_target,
 890	.bios_limit	= acpi_processor_get_bios_limit,
 891	.init		= acpi_cpufreq_cpu_init,
 892	.exit		= acpi_cpufreq_cpu_exit,
 893	.resume		= acpi_cpufreq_resume,
 894	.name		= "acpi-cpufreq",
 
 895	.attr		= acpi_cpufreq_attr,
 896	.set_boost      = _store_boost,
 897};
 898
 899static void __init acpi_cpufreq_boost_init(void)
 900{
 901	if (boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA)) {
 902		msrs = msrs_alloc();
 903
 904		if (!msrs)
 905			return;
 906
 907		acpi_cpufreq_driver.boost_supported = true;
 908		acpi_cpufreq_driver.boost_enabled = boost_state(0);
 909
 910		cpu_notifier_register_begin();
 911
 912		/* Force all MSRs to the same value */
 913		boost_set_msrs(acpi_cpufreq_driver.boost_enabled,
 914			       cpu_online_mask);
 915
 916		__register_cpu_notifier(&boost_nb);
 917
 918		cpu_notifier_register_done();
 919	}
 920}
 921
 922static void acpi_cpufreq_boost_exit(void)
 923{
 924	if (msrs) {
 925		unregister_cpu_notifier(&boost_nb);
 926
 927		msrs_free(msrs);
 928		msrs = NULL;
 929	}
 930}
 931
 932static int __init acpi_cpufreq_init(void)
 933{
 934	int ret;
 935
 936	if (acpi_disabled)
 937		return -ENODEV;
 938
 939	/* don't keep reloading if cpufreq_driver exists */
 940	if (cpufreq_get_current_driver())
 941		return -EEXIST;
 942
 943	pr_debug("acpi_cpufreq_init\n");
 944
 945	ret = acpi_cpufreq_early_init();
 946	if (ret)
 947		return ret;
 948
 949#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 950	/* this is a sysfs file with a strange name and an even stranger
 951	 * semantic - per CPU instantiation, but system global effect.
 952	 * Lets enable it only on AMD CPUs for compatibility reasons and
 953	 * only if configured. This is considered legacy code, which
 954	 * will probably be removed at some point in the future.
 955	 */
 956	if (check_amd_hwpstate_cpu(0)) {
 957		struct freq_attr **iter;
 958
 959		pr_debug("adding sysfs entry for cpb\n");
 960
 961		for (iter = acpi_cpufreq_attr; *iter != NULL; iter++)
 962			;
 963
 964		/* make sure there is a terminator behind it */
 965		if (iter[1] == NULL)
 966			*iter = &cpb;
 967	}
 968#endif
 969	acpi_cpufreq_boost_init();
 970
 971	ret = cpufreq_register_driver(&acpi_cpufreq_driver);
 972	if (ret) {
 973		free_acpi_perf_data();
 974		acpi_cpufreq_boost_exit();
 975	}
 976	return ret;
 977}
 978
 979static void __exit acpi_cpufreq_exit(void)
 980{
 981	pr_debug("acpi_cpufreq_exit\n");
 982
 983	acpi_cpufreq_boost_exit();
 984
 985	cpufreq_unregister_driver(&acpi_cpufreq_driver);
 986
 987	free_acpi_perf_data();
 988}
 989
 990module_param(acpi_pstate_strict, uint, 0644);
 991MODULE_PARM_DESC(acpi_pstate_strict,
 992	"value 0 or non-zero. non-zero -> strict ACPI checks are "
 993	"performed during frequency changes.");
 994
 995late_initcall(acpi_cpufreq_init);
 996module_exit(acpi_cpufreq_exit);
 997
 998static const struct x86_cpu_id acpi_cpufreq_ids[] = {
 999	X86_FEATURE_MATCH(X86_FEATURE_ACPI),
1000	X86_FEATURE_MATCH(X86_FEATURE_HW_PSTATE),
1001	{}
1002};
1003MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1004
1005static const struct acpi_device_id processor_device_ids[] = {
1006	{ACPI_PROCESSOR_OBJECT_HID, },
1007	{ACPI_PROCESSOR_DEVICE_HID, },
1008	{},
1009};
1010MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1011
1012MODULE_ALIAS("acpi");