Linux Audio

Check our new training course

Loading...
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");
v6.2
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * acpi-cpufreq.c - ACPI Processor P-States Driver
   4 *
   5 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   6 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   7 *  Copyright (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de>
   8 *  Copyright (C) 2006       Denis Sadykov <denis.m.sadykov@intel.com>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   9 */
  10
  11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  12
  13#include <linux/kernel.h>
  14#include <linux/module.h>
  15#include <linux/init.h>
  16#include <linux/smp.h>
  17#include <linux/sched.h>
  18#include <linux/cpufreq.h>
  19#include <linux/compiler.h>
  20#include <linux/dmi.h>
  21#include <linux/slab.h>
  22#include <linux/string_helpers.h>
  23
  24#include <linux/acpi.h>
  25#include <linux/io.h>
  26#include <linux/delay.h>
  27#include <linux/uaccess.h>
  28
  29#include <acpi/processor.h>
  30#include <acpi/cppc_acpi.h>
  31
  32#include <asm/msr.h>
  33#include <asm/processor.h>
  34#include <asm/cpufeature.h>
  35#include <asm/cpu_device_id.h>
  36
  37MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
  38MODULE_DESCRIPTION("ACPI Processor P-States Driver");
  39MODULE_LICENSE("GPL");
  40
  41enum {
  42	UNDEFINED_CAPABLE = 0,
  43	SYSTEM_INTEL_MSR_CAPABLE,
  44	SYSTEM_AMD_MSR_CAPABLE,
  45	SYSTEM_IO_CAPABLE,
  46};
  47
  48#define INTEL_MSR_RANGE		(0xffff)
  49#define AMD_MSR_RANGE		(0x7)
  50#define HYGON_MSR_RANGE		(0x7)
  51
  52#define MSR_K7_HWCR_CPB_DIS	(1ULL << 25)
  53
  54struct acpi_cpufreq_data {
 
 
  55	unsigned int resume;
  56	unsigned int cpu_feature;
  57	unsigned int acpi_perf_cpu;
  58	cpumask_var_t freqdomain_cpus;
  59	void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);
  60	u32 (*cpu_freq_read)(struct acpi_pct_register *reg);
  61};
  62
 
 
  63/* acpi_perf_data is a pointer to percpu data. */
  64static struct acpi_processor_performance __percpu *acpi_perf_data;
  65
  66static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
  67{
  68	return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
  69}
  70
  71static struct cpufreq_driver acpi_cpufreq_driver;
  72
  73static unsigned int acpi_pstate_strict;
  74
  75static bool boost_state(unsigned int cpu)
  76{
  77	u32 lo, hi;
  78	u64 msr;
  79
  80	switch (boot_cpu_data.x86_vendor) {
  81	case X86_VENDOR_INTEL:
  82	case X86_VENDOR_CENTAUR:
  83	case X86_VENDOR_ZHAOXIN:
  84		rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
  85		msr = lo | ((u64)hi << 32);
  86		return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
  87	case X86_VENDOR_HYGON:
  88	case X86_VENDOR_AMD:
  89		rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
  90		msr = lo | ((u64)hi << 32);
  91		return !(msr & MSR_K7_HWCR_CPB_DIS);
  92	}
  93	return false;
  94}
  95
  96static int boost_set_msr(bool enable)
  97{
  98	u32 msr_addr;
  99	u64 msr_mask, val;
 100
 101	switch (boot_cpu_data.x86_vendor) {
 102	case X86_VENDOR_INTEL:
 103	case X86_VENDOR_CENTAUR:
 104	case X86_VENDOR_ZHAOXIN:
 105		msr_addr = MSR_IA32_MISC_ENABLE;
 106		msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
 107		break;
 108	case X86_VENDOR_HYGON:
 109	case X86_VENDOR_AMD:
 110		msr_addr = MSR_K7_HWCR;
 111		msr_mask = MSR_K7_HWCR_CPB_DIS;
 112		break;
 113	default:
 114		return -EINVAL;
 115	}
 116
 117	rdmsrl(msr_addr, val);
 118
 119	if (enable)
 120		val &= ~msr_mask;
 121	else
 122		val |= msr_mask;
 123
 124	wrmsrl(msr_addr, val);
 125	return 0;
 126}
 127
 128static void boost_set_msr_each(void *p_en)
 129{
 130	bool enable = (bool) p_en;
 131
 132	boost_set_msr(enable);
 133}
 134
 135static int set_boost(struct cpufreq_policy *policy, int val)
 136{
 137	on_each_cpu_mask(policy->cpus, boost_set_msr_each,
 138			 (void *)(long)val, 1);
 139	pr_debug("CPU %*pbl: Core Boosting %s.\n",
 140		 cpumask_pr_args(policy->cpus), str_enabled_disabled(val));
 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 = policy->driver_data;
 148
 149	if (unlikely(!data))
 150		return -ENODEV;
 151
 152	return cpufreq_show_cpus(data->freqdomain_cpus, buf);
 153}
 154
 155cpufreq_freq_attr_ro(freqdomain_cpus);
 156
 157#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 158static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
 159			 size_t count)
 160{
 161	int ret;
 162	unsigned int val = 0;
 163
 164	if (!acpi_cpufreq_driver.set_boost)
 165		return -EINVAL;
 166
 167	ret = kstrtouint(buf, 10, &val);
 168	if (ret || val > 1)
 169		return -EINVAL;
 170
 171	cpus_read_lock();
 172	set_boost(policy, val);
 173	cpus_read_unlock();
 174
 175	return 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(struct cpufreq_policy *policy, u32 value)
 201{
 202	struct acpi_cpufreq_data *data = policy->driver_data;
 203	struct acpi_processor_performance *perf;
 204	int i;
 205
 206	perf = to_perf_data(data);
 207
 208	for (i = 0; i < perf->state_count; i++) {
 209		if (value == perf->states[i].status)
 210			return policy->freq_table[i].frequency;
 211	}
 212	return 0;
 213}
 214
 215static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
 216{
 217	struct acpi_cpufreq_data *data = policy->driver_data;
 218	struct cpufreq_frequency_table *pos;
 219	struct acpi_processor_performance *perf;
 220
 221	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
 222		msr &= AMD_MSR_RANGE;
 223	else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
 224		msr &= HYGON_MSR_RANGE;
 225	else
 226		msr &= INTEL_MSR_RANGE;
 227
 228	perf = to_perf_data(data);
 229
 230	cpufreq_for_each_entry(pos, policy->freq_table)
 231		if (msr == perf->states[pos->driver_data].status)
 232			return pos->frequency;
 233	return policy->freq_table[0].frequency;
 234}
 235
 236static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
 237{
 238	struct acpi_cpufreq_data *data = policy->driver_data;
 239
 240	switch (data->cpu_feature) {
 241	case SYSTEM_INTEL_MSR_CAPABLE:
 242	case SYSTEM_AMD_MSR_CAPABLE:
 243		return extract_msr(policy, val);
 244	case SYSTEM_IO_CAPABLE:
 245		return extract_io(policy, val);
 246	default:
 247		return 0;
 248	}
 249}
 250
 251static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
 252{
 253	u32 val, dummy __always_unused;
 254
 255	rdmsr(MSR_IA32_PERF_CTL, val, dummy);
 256	return val;
 257}
 258
 259static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
 260{
 261	u32 lo, hi;
 262
 263	rdmsr(MSR_IA32_PERF_CTL, lo, hi);
 264	lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
 265	wrmsr(MSR_IA32_PERF_CTL, lo, hi);
 266}
 267
 268static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
 269{
 270	u32 val, dummy __always_unused;
 271
 272	rdmsr(MSR_AMD_PERF_CTL, val, dummy);
 273	return val;
 274}
 275
 276static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
 277{
 278	wrmsr(MSR_AMD_PERF_CTL, val, 0);
 279}
 280
 281static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
 282{
 283	u32 val;
 284
 285	acpi_os_read_port(reg->address, &val, reg->bit_width);
 286	return val;
 287}
 288
 289static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
 290{
 291	acpi_os_write_port(reg->address, val, reg->bit_width);
 292}
 293
 294struct drv_cmd {
 295	struct acpi_pct_register *reg;
 
 
 
 
 
 296	u32 val;
 297	union {
 298		void (*write)(struct acpi_pct_register *reg, u32 val);
 299		u32 (*read)(struct acpi_pct_register *reg);
 300	} func;
 301};
 302
 303/* Called via smp_call_function_single(), on the target CPU */
 304static void do_drv_read(void *_cmd)
 305{
 306	struct drv_cmd *cmd = _cmd;
 
 307
 308	cmd->val = cmd->func.read(cmd->reg);
 
 
 
 
 
 
 
 
 
 
 
 309}
 310
 311static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
 
 312{
 313	struct acpi_processor_performance *perf = to_perf_data(data);
 314	struct drv_cmd cmd = {
 315		.reg = &perf->control_register,
 316		.func.read = data->cpu_freq_read,
 317	};
 318	int err;
 319
 320	err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
 321	WARN_ON_ONCE(err);	/* smp_call_function_any() was buggy? */
 322	return cmd.val;
 
 
 
 
 
 
 
 
 
 
 
 323}
 324
 325/* Called via smp_call_function_many(), on the target CPUs */
 326static void do_drv_write(void *_cmd)
 327{
 328	struct drv_cmd *cmd = _cmd;
 
 329
 330	cmd->func.write(cmd->reg, cmd->val);
 
 331}
 332
 333static void drv_write(struct acpi_cpufreq_data *data,
 334		      const struct cpumask *mask, u32 val)
 335{
 336	struct acpi_processor_performance *perf = to_perf_data(data);
 337	struct drv_cmd cmd = {
 338		.reg = &perf->control_register,
 339		.val = val,
 340		.func.write = data->cpu_freq_write,
 341	};
 342	int this_cpu;
 343
 344	this_cpu = get_cpu();
 345	if (cpumask_test_cpu(this_cpu, mask))
 346		do_drv_write(&cmd);
 347
 348	smp_call_function_many(mask, do_drv_write, &cmd, 1);
 349	put_cpu();
 350}
 351
 352static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
 353{
 354	u32 val;
 
 355
 356	if (unlikely(cpumask_empty(mask)))
 357		return 0;
 358
 359	val = drv_read(data, mask);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 360
 361	pr_debug("%s = %u\n", __func__, val);
 362
 363	return val;
 364}
 365
 366static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 367{
 368	struct acpi_cpufreq_data *data;
 369	struct cpufreq_policy *policy;
 370	unsigned int freq;
 371	unsigned int cached_freq;
 372
 373	pr_debug("%s (%d)\n", __func__, cpu);
 374
 375	policy = cpufreq_cpu_get_raw(cpu);
 376	if (unlikely(!policy))
 377		return 0;
 
 378
 379	data = policy->driver_data;
 380	if (unlikely(!data || !policy->freq_table))
 381		return 0;
 382
 383	cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;
 384	freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));
 385	if (freq != cached_freq) {
 386		/*
 387		 * The dreaded BIOS frequency change behind our back.
 388		 * Force set the frequency on next target call.
 389		 */
 390		data->resume = 1;
 391	}
 392
 393	pr_debug("cur freq = %u\n", freq);
 394
 395	return freq;
 396}
 397
 398static unsigned int check_freqs(struct cpufreq_policy *policy,
 399				const struct cpumask *mask, unsigned int freq)
 400{
 401	struct acpi_cpufreq_data *data = policy->driver_data;
 402	unsigned int cur_freq;
 403	unsigned int i;
 404
 405	for (i = 0; i < 100; i++) {
 406		cur_freq = extract_freq(policy, get_cur_val(mask, data));
 407		if (cur_freq == freq)
 408			return 1;
 409		udelay(10);
 410	}
 411	return 0;
 412}
 413
 414static int acpi_cpufreq_target(struct cpufreq_policy *policy,
 415			       unsigned int index)
 416{
 417	struct acpi_cpufreq_data *data = policy->driver_data;
 418	struct acpi_processor_performance *perf;
 419	const struct cpumask *mask;
 
 
 420	unsigned int next_perf_state = 0; /* Index into perf table */
 
 421	int result = 0;
 422
 423	if (unlikely(!data)) {
 
 
 
 424		return -ENODEV;
 425	}
 426
 427	perf = to_perf_data(data);
 428	next_perf_state = policy->freq_table[index].driver_data;
 
 
 
 
 
 
 
 
 
 429	if (perf->state == next_perf_state) {
 430		if (unlikely(data->resume)) {
 431			pr_debug("Called after resume, resetting to P%d\n",
 432				next_perf_state);
 433			data->resume = 0;
 434		} else {
 435			pr_debug("Already at target state (P%d)\n",
 436				next_perf_state);
 437			return 0;
 438		}
 439	}
 440
 441	/*
 442	 * The core won't allow CPUs to go away until the governor has been
 443	 * stopped, so we can rely on the stability of policy->cpus.
 444	 */
 445	mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
 446		cpumask_of(policy->cpu) : policy->cpus;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 447
 448	drv_write(data, mask, perf->states[next_perf_state].control);
 449
 450	if (acpi_pstate_strict) {
 451		if (!check_freqs(policy, mask,
 452				 policy->freq_table[index].frequency)) {
 453			pr_debug("%s (%d)\n", __func__, policy->cpu);
 454			result = -EAGAIN;
 
 455		}
 456	}
 457
 458	if (!result)
 459		perf->state = next_perf_state;
 
 
 
 460
 
 461	return result;
 462}
 463
 464static unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
 465					     unsigned int target_freq)
 466{
 467	struct acpi_cpufreq_data *data = policy->driver_data;
 468	struct acpi_processor_performance *perf;
 469	struct cpufreq_frequency_table *entry;
 470	unsigned int next_perf_state, next_freq, index;
 471
 472	/*
 473	 * Find the closest frequency above target_freq.
 474	 */
 475	if (policy->cached_target_freq == target_freq)
 476		index = policy->cached_resolved_idx;
 477	else
 478		index = cpufreq_table_find_index_dl(policy, target_freq,
 479						    false);
 480
 481	entry = &policy->freq_table[index];
 482	next_freq = entry->frequency;
 483	next_perf_state = entry->driver_data;
 484
 485	perf = to_perf_data(data);
 486	if (perf->state == next_perf_state) {
 487		if (unlikely(data->resume))
 488			data->resume = 0;
 489		else
 490			return next_freq;
 491	}
 492
 493	data->cpu_freq_write(&perf->control_register,
 494			     perf->states[next_perf_state].control);
 495	perf->state = next_perf_state;
 496	return next_freq;
 497}
 498
 499static unsigned long
 500acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 501{
 502	struct acpi_processor_performance *perf;
 503
 504	perf = to_perf_data(data);
 505	if (cpu_khz) {
 506		/* search the closest match to cpu_khz */
 507		unsigned int i;
 508		unsigned long freq;
 509		unsigned long freqn = perf->states[0].core_frequency * 1000;
 510
 511		for (i = 0; i < (perf->state_count-1); i++) {
 512			freq = freqn;
 513			freqn = perf->states[i+1].core_frequency * 1000;
 514			if ((2 * cpu_khz) > (freqn + freq)) {
 515				perf->state = i;
 516				return freq;
 517			}
 518		}
 519		perf->state = perf->state_count-1;
 520		return freqn;
 521	} else {
 522		/* assume CPU is at P0... */
 523		perf->state = 0;
 524		return perf->states[0].core_frequency * 1000;
 525	}
 526}
 527
 528static void free_acpi_perf_data(void)
 529{
 530	unsigned int i;
 531
 532	/* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
 533	for_each_possible_cpu(i)
 534		free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
 535				 ->shared_cpu_map);
 536	free_percpu(acpi_perf_data);
 537}
 538
 539static int cpufreq_boost_down_prep(unsigned int cpu)
 540{
 541	/*
 542	 * Clear the boost-disable bit on the CPU_DOWN path so that
 543	 * this cpu cannot block the remaining ones from boosting.
 544	 */
 545	return boost_set_msr(1);
 546}
 547
 548/*
 549 * acpi_cpufreq_early_init - initialize ACPI P-States library
 550 *
 551 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 552 * in order to determine correct frequency and voltage pairings. We can
 553 * do _PDC and _PSD and find out the processor dependency for the
 554 * actual init that will happen later...
 555 */
 556static int __init acpi_cpufreq_early_init(void)
 557{
 558	unsigned int i;
 559	pr_debug("%s\n", __func__);
 560
 561	acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
 562	if (!acpi_perf_data) {
 563		pr_debug("Memory allocation error for acpi_perf_data.\n");
 564		return -ENOMEM;
 565	}
 566	for_each_possible_cpu(i) {
 567		if (!zalloc_cpumask_var_node(
 568			&per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
 569			GFP_KERNEL, cpu_to_node(i))) {
 570
 571			/* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
 572			free_acpi_perf_data();
 573			return -ENOMEM;
 574		}
 575	}
 576
 577	/* Do initialization in ACPI core */
 578	acpi_processor_preregister_performance(acpi_perf_data);
 579	return 0;
 580}
 581
 582#ifdef CONFIG_SMP
 583/*
 584 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 585 * or do it in BIOS firmware and won't inform about it to OS. If not
 586 * detected, this has a side effect of making CPU run at a different speed
 587 * than OS intended it to run at. Detect it and handle it cleanly.
 588 */
 589static int bios_with_sw_any_bug;
 590
 591static int sw_any_bug_found(const struct dmi_system_id *d)
 592{
 593	bios_with_sw_any_bug = 1;
 594	return 0;
 595}
 596
 597static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 598	{
 599		.callback = sw_any_bug_found,
 600		.ident = "Supermicro Server X6DLP",
 601		.matches = {
 602			DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 603			DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 604			DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 605		},
 606	},
 607	{ }
 608};
 609
 610static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
 611{
 612	/* Intel Xeon Processor 7100 Series Specification Update
 613	 * https://www.intel.com/Assets/PDF/specupdate/314554.pdf
 614	 * AL30: A Machine Check Exception (MCE) Occurring during an
 615	 * Enhanced Intel SpeedStep Technology Ratio Change May Cause
 616	 * Both Processor Cores to Lock Up. */
 617	if (c->x86_vendor == X86_VENDOR_INTEL) {
 618		if ((c->x86 == 15) &&
 619		    (c->x86_model == 6) &&
 620		    (c->x86_stepping == 8)) {
 621			pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");
 
 
 
 622			return -ENODEV;
 623		    }
 624		}
 625	return 0;
 626}
 627#endif
 628
 629#ifdef CONFIG_ACPI_CPPC_LIB
 630static u64 get_max_boost_ratio(unsigned int cpu)
 631{
 632	struct cppc_perf_caps perf_caps;
 633	u64 highest_perf, nominal_perf;
 634	int ret;
 635
 636	if (acpi_pstate_strict)
 637		return 0;
 638
 639	ret = cppc_get_perf_caps(cpu, &perf_caps);
 640	if (ret) {
 641		pr_debug("CPU%d: Unable to get performance capabilities (%d)\n",
 642			 cpu, ret);
 643		return 0;
 644	}
 645
 646	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
 647		highest_perf = amd_get_highest_perf();
 648	else
 649		highest_perf = perf_caps.highest_perf;
 650
 651	nominal_perf = perf_caps.nominal_perf;
 652
 653	if (!highest_perf || !nominal_perf) {
 654		pr_debug("CPU%d: highest or nominal performance missing\n", cpu);
 655		return 0;
 656	}
 657
 658	if (highest_perf < nominal_perf) {
 659		pr_debug("CPU%d: nominal performance above highest\n", cpu);
 660		return 0;
 661	}
 662
 663	return div_u64(highest_perf << SCHED_CAPACITY_SHIFT, nominal_perf);
 664}
 665#else
 666static inline u64 get_max_boost_ratio(unsigned int cpu) { return 0; }
 667#endif
 668
 669static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 670{
 671	struct cpufreq_frequency_table *freq_table;
 672	struct acpi_processor_performance *perf;
 
 673	struct acpi_cpufreq_data *data;
 674	unsigned int cpu = policy->cpu;
 675	struct cpuinfo_x86 *c = &cpu_data(cpu);
 676	unsigned int valid_states = 0;
 677	unsigned int result = 0;
 678	u64 max_boost_ratio;
 679	unsigned int i;
 680#ifdef CONFIG_SMP
 681	static int blacklisted;
 682#endif
 683
 684	pr_debug("%s\n", __func__);
 685
 686#ifdef CONFIG_SMP
 687	if (blacklisted)
 688		return blacklisted;
 689	blacklisted = acpi_cpufreq_blacklist(c);
 690	if (blacklisted)
 691		return blacklisted;
 692#endif
 693
 694	data = kzalloc(sizeof(*data), GFP_KERNEL);
 695	if (!data)
 696		return -ENOMEM;
 697
 698	if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
 699		result = -ENOMEM;
 700		goto err_free;
 701	}
 702
 703	perf = per_cpu_ptr(acpi_perf_data, cpu);
 704	data->acpi_perf_cpu = cpu;
 705	policy->driver_data = data;
 706
 707	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 708		acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 709
 710	result = acpi_processor_register_performance(perf, cpu);
 711	if (result)
 712		goto err_free_mask;
 713
 
 714	policy->shared_type = perf->shared_type;
 715
 716	/*
 717	 * Will let policy->cpus know about dependency only when software
 718	 * coordination is required.
 719	 */
 720	if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 721	    policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 722		cpumask_copy(policy->cpus, perf->shared_cpu_map);
 723	}
 724	cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
 725
 726#ifdef CONFIG_SMP
 727	dmi_check_system(sw_any_bug_dmi_table);
 728	if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
 729		policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 730		cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
 731	}
 732
 733	if (check_amd_hwpstate_cpu(cpu) && boot_cpu_data.x86 < 0x19 &&
 734	    !acpi_pstate_strict) {
 735		cpumask_clear(policy->cpus);
 736		cpumask_set_cpu(cpu, policy->cpus);
 737		cpumask_copy(data->freqdomain_cpus,
 738			     topology_sibling_cpumask(cpu));
 739		policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
 740		pr_info_once("overriding BIOS provided _PSD data\n");
 741	}
 742#endif
 743
 744	/* capability check */
 745	if (perf->state_count <= 1) {
 746		pr_debug("No P-States\n");
 747		result = -ENODEV;
 748		goto err_unreg;
 749	}
 750
 751	if (perf->control_register.space_id != perf->status_register.space_id) {
 752		result = -ENODEV;
 753		goto err_unreg;
 754	}
 755
 756	switch (perf->control_register.space_id) {
 757	case ACPI_ADR_SPACE_SYSTEM_IO:
 758		if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 759		    boot_cpu_data.x86 == 0xf) {
 760			pr_debug("AMD K8 systems must use native drivers.\n");
 761			result = -ENODEV;
 762			goto err_unreg;
 763		}
 764		pr_debug("SYSTEM IO addr space\n");
 765		data->cpu_feature = SYSTEM_IO_CAPABLE;
 766		data->cpu_freq_read = cpu_freq_read_io;
 767		data->cpu_freq_write = cpu_freq_write_io;
 768		break;
 769	case ACPI_ADR_SPACE_FIXED_HARDWARE:
 770		pr_debug("HARDWARE addr space\n");
 771		if (check_est_cpu(cpu)) {
 772			data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 773			data->cpu_freq_read = cpu_freq_read_intel;
 774			data->cpu_freq_write = cpu_freq_write_intel;
 775			break;
 776		}
 777		if (check_amd_hwpstate_cpu(cpu)) {
 778			data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
 779			data->cpu_freq_read = cpu_freq_read_amd;
 780			data->cpu_freq_write = cpu_freq_write_amd;
 781			break;
 782		}
 783		result = -ENODEV;
 784		goto err_unreg;
 785	default:
 786		pr_debug("Unknown addr space %d\n",
 787			(u32) (perf->control_register.space_id));
 788		result = -ENODEV;
 789		goto err_unreg;
 790	}
 791
 792	freq_table = kcalloc(perf->state_count + 1, sizeof(*freq_table),
 793			     GFP_KERNEL);
 794	if (!freq_table) {
 795		result = -ENOMEM;
 796		goto err_unreg;
 797	}
 798
 799	/* detect transition latency */
 800	policy->cpuinfo.transition_latency = 0;
 801	for (i = 0; i < perf->state_count; i++) {
 802		if ((perf->states[i].transition_latency * 1000) >
 803		    policy->cpuinfo.transition_latency)
 804			policy->cpuinfo.transition_latency =
 805			    perf->states[i].transition_latency * 1000;
 806	}
 807
 808	/* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
 809	if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
 810	    policy->cpuinfo.transition_latency > 20 * 1000) {
 811		policy->cpuinfo.transition_latency = 20 * 1000;
 812		pr_info_once("P-state transition latency capped at 20 uS\n");
 
 813	}
 814
 815	/* table init */
 816	for (i = 0; i < perf->state_count; i++) {
 817		if (i > 0 && perf->states[i].core_frequency >=
 818		    freq_table[valid_states-1].frequency / 1000)
 819			continue;
 820
 821		freq_table[valid_states].driver_data = i;
 822		freq_table[valid_states].frequency =
 823		    perf->states[i].core_frequency * 1000;
 824		valid_states++;
 825	}
 826	freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 
 827
 828	max_boost_ratio = get_max_boost_ratio(cpu);
 829	if (max_boost_ratio) {
 830		unsigned int freq = freq_table[0].frequency;
 831
 832		/*
 833		 * Because the loop above sorts the freq_table entries in the
 834		 * descending order, freq is the maximum frequency in the table.
 835		 * Assume that it corresponds to the CPPC nominal frequency and
 836		 * use it to set cpuinfo.max_freq.
 837		 */
 838		policy->cpuinfo.max_freq = freq * max_boost_ratio >> SCHED_CAPACITY_SHIFT;
 839	} else {
 840		/*
 841		 * If the maximum "boost" frequency is unknown, ask the arch
 842		 * scale-invariance code to use the "nominal" performance for
 843		 * CPU utilization scaling so as to prevent the schedutil
 844		 * governor from selecting inadequate CPU frequencies.
 845		 */
 846		arch_set_max_freq_ratio(true);
 847	}
 848
 849	policy->freq_table = freq_table;
 850	perf->state = 0;
 851
 852	switch (perf->control_register.space_id) {
 853	case ACPI_ADR_SPACE_SYSTEM_IO:
 854		/*
 855		 * The core will not set policy->cur, because
 856		 * cpufreq_driver->get is NULL, so we need to set it here.
 857		 * However, we have to guess it, because the current speed is
 858		 * unknown and not detectable via IO ports.
 859		 */
 860		policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 861		break;
 862	case ACPI_ADR_SPACE_FIXED_HARDWARE:
 863		acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 
 864		break;
 865	default:
 866		break;
 867	}
 868
 869	/* notify BIOS that we exist */
 870	acpi_processor_notify_smm(THIS_MODULE);
 871
 
 
 
 
 872	pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
 873	for (i = 0; i < perf->state_count; i++)
 874		pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
 875			(i == perf->state ? '*' : ' '), i,
 876			(u32) perf->states[i].core_frequency,
 877			(u32) perf->states[i].power,
 878			(u32) perf->states[i].transition_latency);
 879
 
 
 880	/*
 881	 * the first call to ->target() should result in us actually
 882	 * writing something to the appropriate registers.
 883	 */
 884	data->resume = 1;
 885
 886	policy->fast_switch_possible = !acpi_pstate_strict &&
 887		!(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);
 888
 889	if (perf->states[0].core_frequency * 1000 != freq_table[0].frequency)
 890		pr_warn(FW_WARN "P-state 0 is not max freq\n");
 891
 892	if (acpi_cpufreq_driver.set_boost)
 893		set_boost(policy, acpi_cpufreq_driver.boost_enabled);
 894
 895	return result;
 896
 
 
 897err_unreg:
 898	acpi_processor_unregister_performance(cpu);
 899err_free_mask:
 900	free_cpumask_var(data->freqdomain_cpus);
 901err_free:
 902	kfree(data);
 903	policy->driver_data = NULL;
 904
 905	return result;
 906}
 907
 908static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 909{
 910	struct acpi_cpufreq_data *data = policy->driver_data;
 911
 912	pr_debug("%s\n", __func__);
 913
 914	cpufreq_boost_down_prep(policy->cpu);
 915	policy->fast_switch_possible = false;
 916	policy->driver_data = NULL;
 917	acpi_processor_unregister_performance(data->acpi_perf_cpu);
 918	free_cpumask_var(data->freqdomain_cpus);
 919	kfree(policy->freq_table);
 920	kfree(data);
 
 921
 922	return 0;
 923}
 924
 925static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 926{
 927	struct acpi_cpufreq_data *data = policy->driver_data;
 928
 929	pr_debug("%s\n", __func__);
 930
 931	data->resume = 1;
 932
 933	return 0;
 934}
 935
 936static struct freq_attr *acpi_cpufreq_attr[] = {
 937	&cpufreq_freq_attr_scaling_available_freqs,
 938	&freqdomain_cpus,
 939#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 940	&cpb,
 941#endif
 942	NULL,
 943};
 944
 945static struct cpufreq_driver acpi_cpufreq_driver = {
 946	.verify		= cpufreq_generic_frequency_table_verify,
 947	.target_index	= acpi_cpufreq_target,
 948	.fast_switch	= acpi_cpufreq_fast_switch,
 949	.bios_limit	= acpi_processor_get_bios_limit,
 950	.init		= acpi_cpufreq_cpu_init,
 951	.exit		= acpi_cpufreq_cpu_exit,
 952	.resume		= acpi_cpufreq_resume,
 953	.name		= "acpi-cpufreq",
 
 954	.attr		= acpi_cpufreq_attr,
 955};
 956
 957static void __init acpi_cpufreq_boost_init(void)
 958{
 959	if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA))) {
 960		pr_debug("Boost capabilities not present in the processor\n");
 961		return;
 962	}
 963
 964	acpi_cpufreq_driver.set_boost = set_boost;
 965	acpi_cpufreq_driver.boost_enabled = boost_state(0);
 966}
 967
 968static int __init acpi_cpufreq_init(void)
 969{
 970	int ret;
 971
 972	if (acpi_disabled)
 973		return -ENODEV;
 974
 975	/* don't keep reloading if cpufreq_driver exists */
 976	if (cpufreq_get_current_driver())
 977		return -EEXIST;
 978
 979	pr_debug("%s\n", __func__);
 980
 981	ret = acpi_cpufreq_early_init();
 982	if (ret)
 983		return ret;
 984
 985#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 986	/* this is a sysfs file with a strange name and an even stranger
 987	 * semantic - per CPU instantiation, but system global effect.
 988	 * Lets enable it only on AMD CPUs for compatibility reasons and
 989	 * only if configured. This is considered legacy code, which
 990	 * will probably be removed at some point in the future.
 991	 */
 992	if (!check_amd_hwpstate_cpu(0)) {
 993		struct freq_attr **attr;
 994
 995		pr_debug("CPB unsupported, do not expose it\n");
 996
 997		for (attr = acpi_cpufreq_attr; *attr; attr++)
 998			if (*attr == &cpb) {
 999				*attr = NULL;
1000				break;
1001			}
1002	}
1003#endif
1004	acpi_cpufreq_boost_init();
1005
1006	ret = cpufreq_register_driver(&acpi_cpufreq_driver);
1007	if (ret) {
1008		free_acpi_perf_data();
1009	}
1010	return ret;
1011}
1012
1013static void __exit acpi_cpufreq_exit(void)
1014{
1015	pr_debug("%s\n", __func__);
1016
1017	cpufreq_unregister_driver(&acpi_cpufreq_driver);
1018
1019	free_acpi_perf_data();
1020}
1021
1022module_param(acpi_pstate_strict, uint, 0644);
1023MODULE_PARM_DESC(acpi_pstate_strict,
1024	"value 0 or non-zero. non-zero -> strict ACPI checks are "
1025	"performed during frequency changes.");
1026
1027late_initcall(acpi_cpufreq_init);
1028module_exit(acpi_cpufreq_exit);
1029
1030static const struct x86_cpu_id __maybe_unused acpi_cpufreq_ids[] = {
1031	X86_MATCH_FEATURE(X86_FEATURE_ACPI, NULL),
1032	X86_MATCH_FEATURE(X86_FEATURE_HW_PSTATE, NULL),
1033	{}
1034};
1035MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1036
1037static const struct acpi_device_id __maybe_unused processor_device_ids[] = {
1038	{ACPI_PROCESSOR_OBJECT_HID, },
1039	{ACPI_PROCESSOR_DEVICE_HID, },
1040	{},
1041};
1042MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1043
1044MODULE_ALIAS("acpi");