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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");
v5.14.15
   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
  23#include <linux/acpi.h>
  24#include <linux/io.h>
  25#include <linux/delay.h>
  26#include <linux/uaccess.h>
  27
  28#include <acpi/processor.h>
  29#include <acpi/cppc_acpi.h>
  30
  31#include <asm/msr.h>
  32#include <asm/processor.h>
  33#include <asm/cpufeature.h>
  34#include <asm/cpu_device_id.h>
  35
  36MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
  37MODULE_DESCRIPTION("ACPI Processor P-States Driver");
  38MODULE_LICENSE("GPL");
  39
  40enum {
  41	UNDEFINED_CAPABLE = 0,
  42	SYSTEM_INTEL_MSR_CAPABLE,
  43	SYSTEM_AMD_MSR_CAPABLE,
  44	SYSTEM_IO_CAPABLE,
  45};
  46
  47#define INTEL_MSR_RANGE		(0xffff)
  48#define AMD_MSR_RANGE		(0x7)
  49#define HYGON_MSR_RANGE		(0x7)
  50
  51#define MSR_K7_HWCR_CPB_DIS	(1ULL << 25)
  52
  53struct acpi_cpufreq_data {
 
 
  54	unsigned int resume;
  55	unsigned int cpu_feature;
  56	unsigned int acpi_perf_cpu;
  57	cpumask_var_t freqdomain_cpus;
  58	void (*cpu_freq_write)(struct acpi_pct_register *reg, u32 val);
  59	u32 (*cpu_freq_read)(struct acpi_pct_register *reg);
  60};
  61
 
 
  62/* acpi_perf_data is a pointer to percpu data. */
  63static struct acpi_processor_performance __percpu *acpi_perf_data;
  64
  65static inline struct acpi_processor_performance *to_perf_data(struct acpi_cpufreq_data *data)
  66{
  67	return per_cpu_ptr(acpi_perf_data, data->acpi_perf_cpu);
  68}
  69
  70static struct cpufreq_driver acpi_cpufreq_driver;
  71
  72static unsigned int acpi_pstate_strict;
  73
  74static bool boost_state(unsigned int cpu)
  75{
  76	u32 lo, hi;
  77	u64 msr;
  78
  79	switch (boot_cpu_data.x86_vendor) {
  80	case X86_VENDOR_INTEL:
  81		rdmsr_on_cpu(cpu, MSR_IA32_MISC_ENABLE, &lo, &hi);
  82		msr = lo | ((u64)hi << 32);
  83		return !(msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
  84	case X86_VENDOR_HYGON:
  85	case X86_VENDOR_AMD:
  86		rdmsr_on_cpu(cpu, MSR_K7_HWCR, &lo, &hi);
  87		msr = lo | ((u64)hi << 32);
  88		return !(msr & MSR_K7_HWCR_CPB_DIS);
  89	}
  90	return false;
  91}
  92
  93static int boost_set_msr(bool enable)
  94{
  95	u32 msr_addr;
  96	u64 msr_mask, val;
  97
  98	switch (boot_cpu_data.x86_vendor) {
  99	case X86_VENDOR_INTEL:
 100		msr_addr = MSR_IA32_MISC_ENABLE;
 101		msr_mask = MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
 102		break;
 103	case X86_VENDOR_HYGON:
 104	case X86_VENDOR_AMD:
 105		msr_addr = MSR_K7_HWCR;
 106		msr_mask = MSR_K7_HWCR_CPB_DIS;
 107		break;
 108	default:
 109		return -EINVAL;
 110	}
 111
 112	rdmsrl(msr_addr, val);
 113
 114	if (enable)
 115		val &= ~msr_mask;
 116	else
 117		val |= msr_mask;
 118
 119	wrmsrl(msr_addr, val);
 120	return 0;
 121}
 122
 123static void boost_set_msr_each(void *p_en)
 124{
 125	bool enable = (bool) p_en;
 126
 127	boost_set_msr(enable);
 128}
 129
 130static int set_boost(struct cpufreq_policy *policy, int val)
 131{
 132	on_each_cpu_mask(policy->cpus, boost_set_msr_each,
 133			 (void *)(long)val, 1);
 134	pr_debug("CPU %*pbl: Core Boosting %sabled.\n",
 135		 cpumask_pr_args(policy->cpus), val ? "en" : "dis");
 136
 137	return 0;
 138}
 139
 140static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
 141{
 142	struct acpi_cpufreq_data *data = policy->driver_data;
 143
 144	if (unlikely(!data))
 145		return -ENODEV;
 146
 147	return cpufreq_show_cpus(data->freqdomain_cpus, buf);
 148}
 149
 150cpufreq_freq_attr_ro(freqdomain_cpus);
 151
 152#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 153static ssize_t store_cpb(struct cpufreq_policy *policy, const char *buf,
 154			 size_t count)
 155{
 156	int ret;
 157	unsigned int val = 0;
 158
 159	if (!acpi_cpufreq_driver.set_boost)
 160		return -EINVAL;
 161
 162	ret = kstrtouint(buf, 10, &val);
 163	if (ret || val > 1)
 164		return -EINVAL;
 165
 166	get_online_cpus();
 167	set_boost(policy, val);
 168	put_online_cpus();
 169
 170	return count;
 171}
 172
 173static ssize_t show_cpb(struct cpufreq_policy *policy, char *buf)
 174{
 175	return sprintf(buf, "%u\n", acpi_cpufreq_driver.boost_enabled);
 176}
 177
 178cpufreq_freq_attr_rw(cpb);
 179#endif
 180
 181static int check_est_cpu(unsigned int cpuid)
 182{
 183	struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 184
 185	return cpu_has(cpu, X86_FEATURE_EST);
 186}
 187
 188static int check_amd_hwpstate_cpu(unsigned int cpuid)
 189{
 190	struct cpuinfo_x86 *cpu = &cpu_data(cpuid);
 191
 192	return cpu_has(cpu, X86_FEATURE_HW_PSTATE);
 193}
 194
 195static unsigned extract_io(struct cpufreq_policy *policy, u32 value)
 196{
 197	struct acpi_cpufreq_data *data = policy->driver_data;
 198	struct acpi_processor_performance *perf;
 199	int i;
 200
 201	perf = to_perf_data(data);
 202
 203	for (i = 0; i < perf->state_count; i++) {
 204		if (value == perf->states[i].status)
 205			return policy->freq_table[i].frequency;
 206	}
 207	return 0;
 208}
 209
 210static unsigned extract_msr(struct cpufreq_policy *policy, u32 msr)
 211{
 212	struct acpi_cpufreq_data *data = policy->driver_data;
 213	struct cpufreq_frequency_table *pos;
 214	struct acpi_processor_performance *perf;
 215
 216	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
 217		msr &= AMD_MSR_RANGE;
 218	else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
 219		msr &= HYGON_MSR_RANGE;
 220	else
 221		msr &= INTEL_MSR_RANGE;
 222
 223	perf = to_perf_data(data);
 224
 225	cpufreq_for_each_entry(pos, policy->freq_table)
 226		if (msr == perf->states[pos->driver_data].status)
 227			return pos->frequency;
 228	return policy->freq_table[0].frequency;
 229}
 230
 231static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
 232{
 233	struct acpi_cpufreq_data *data = policy->driver_data;
 234
 235	switch (data->cpu_feature) {
 236	case SYSTEM_INTEL_MSR_CAPABLE:
 237	case SYSTEM_AMD_MSR_CAPABLE:
 238		return extract_msr(policy, val);
 239	case SYSTEM_IO_CAPABLE:
 240		return extract_io(policy, val);
 241	default:
 242		return 0;
 243	}
 244}
 245
 246static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
 247{
 248	u32 val, dummy __always_unused;
 249
 250	rdmsr(MSR_IA32_PERF_CTL, val, dummy);
 251	return val;
 252}
 253
 254static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
 255{
 256	u32 lo, hi;
 257
 258	rdmsr(MSR_IA32_PERF_CTL, lo, hi);
 259	lo = (lo & ~INTEL_MSR_RANGE) | (val & INTEL_MSR_RANGE);
 260	wrmsr(MSR_IA32_PERF_CTL, lo, hi);
 261}
 262
 263static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
 264{
 265	u32 val, dummy __always_unused;
 266
 267	rdmsr(MSR_AMD_PERF_CTL, val, dummy);
 268	return val;
 269}
 270
 271static void cpu_freq_write_amd(struct acpi_pct_register *not_used, u32 val)
 272{
 273	wrmsr(MSR_AMD_PERF_CTL, val, 0);
 274}
 275
 276static u32 cpu_freq_read_io(struct acpi_pct_register *reg)
 277{
 278	u32 val;
 279
 280	acpi_os_read_port(reg->address, &val, reg->bit_width);
 281	return val;
 282}
 283
 284static void cpu_freq_write_io(struct acpi_pct_register *reg, u32 val)
 285{
 286	acpi_os_write_port(reg->address, val, reg->bit_width);
 287}
 288
 289struct drv_cmd {
 290	struct acpi_pct_register *reg;
 
 
 
 
 
 291	u32 val;
 292	union {
 293		void (*write)(struct acpi_pct_register *reg, u32 val);
 294		u32 (*read)(struct acpi_pct_register *reg);
 295	} func;
 296};
 297
 298/* Called via smp_call_function_single(), on the target CPU */
 299static void do_drv_read(void *_cmd)
 300{
 301	struct drv_cmd *cmd = _cmd;
 
 302
 303	cmd->val = cmd->func.read(cmd->reg);
 
 
 
 
 
 
 
 
 
 
 
 304}
 305
 306static u32 drv_read(struct acpi_cpufreq_data *data, const struct cpumask *mask)
 
 307{
 308	struct acpi_processor_performance *perf = to_perf_data(data);
 309	struct drv_cmd cmd = {
 310		.reg = &perf->control_register,
 311		.func.read = data->cpu_freq_read,
 312	};
 313	int err;
 314
 315	err = smp_call_function_any(mask, do_drv_read, &cmd, 1);
 316	WARN_ON_ONCE(err);	/* smp_call_function_any() was buggy? */
 317	return cmd.val;
 
 
 
 
 
 
 
 
 
 
 
 318}
 319
 320/* Called via smp_call_function_many(), on the target CPUs */
 321static void do_drv_write(void *_cmd)
 322{
 323	struct drv_cmd *cmd = _cmd;
 
 324
 325	cmd->func.write(cmd->reg, cmd->val);
 
 326}
 327
 328static void drv_write(struct acpi_cpufreq_data *data,
 329		      const struct cpumask *mask, u32 val)
 330{
 331	struct acpi_processor_performance *perf = to_perf_data(data);
 332	struct drv_cmd cmd = {
 333		.reg = &perf->control_register,
 334		.val = val,
 335		.func.write = data->cpu_freq_write,
 336	};
 337	int this_cpu;
 338
 339	this_cpu = get_cpu();
 340	if (cpumask_test_cpu(this_cpu, mask))
 341		do_drv_write(&cmd);
 342
 343	smp_call_function_many(mask, do_drv_write, &cmd, 1);
 344	put_cpu();
 345}
 346
 347static u32 get_cur_val(const struct cpumask *mask, struct acpi_cpufreq_data *data)
 348{
 349	u32 val;
 
 350
 351	if (unlikely(cpumask_empty(mask)))
 352		return 0;
 353
 354	val = drv_read(data, mask);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 355
 356	pr_debug("%s = %u\n", __func__, val);
 357
 358	return val;
 359}
 360
 361static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 362{
 363	struct acpi_cpufreq_data *data;
 364	struct cpufreq_policy *policy;
 365	unsigned int freq;
 366	unsigned int cached_freq;
 367
 368	pr_debug("%s (%d)\n", __func__, cpu);
 369
 370	policy = cpufreq_cpu_get_raw(cpu);
 371	if (unlikely(!policy))
 372		return 0;
 373
 374	data = policy->driver_data;
 375	if (unlikely(!data || !policy->freq_table))
 376		return 0;
 
 377
 378	cached_freq = policy->freq_table[to_perf_data(data)->state].frequency;
 379	freq = extract_freq(policy, get_cur_val(cpumask_of(cpu), data));
 380	if (freq != cached_freq) {
 381		/*
 382		 * The dreaded BIOS frequency change behind our back.
 383		 * Force set the frequency on next target call.
 384		 */
 385		data->resume = 1;
 386	}
 387
 388	pr_debug("cur freq = %u\n", freq);
 389
 390	return freq;
 391}
 392
 393static unsigned int check_freqs(struct cpufreq_policy *policy,
 394				const struct cpumask *mask, unsigned int freq)
 395{
 396	struct acpi_cpufreq_data *data = policy->driver_data;
 397	unsigned int cur_freq;
 398	unsigned int i;
 399
 400	for (i = 0; i < 100; i++) {
 401		cur_freq = extract_freq(policy, 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 = policy->driver_data;
 413	struct acpi_processor_performance *perf;
 414	const struct cpumask *mask;
 
 
 415	unsigned int next_perf_state = 0; /* Index into perf table */
 
 416	int result = 0;
 417
 418	if (unlikely(!data)) {
 
 
 
 419		return -ENODEV;
 420	}
 421
 422	perf = to_perf_data(data);
 423	next_perf_state = policy->freq_table[index].driver_data;
 
 
 
 
 
 
 
 
 
 424	if (perf->state == next_perf_state) {
 425		if (unlikely(data->resume)) {
 426			pr_debug("Called after resume, resetting to P%d\n",
 427				next_perf_state);
 428			data->resume = 0;
 429		} else {
 430			pr_debug("Already at target state (P%d)\n",
 431				next_perf_state);
 432			return 0;
 433		}
 434	}
 435
 436	/*
 437	 * The core won't allow CPUs to go away until the governor has been
 438	 * stopped, so we can rely on the stability of policy->cpus.
 439	 */
 440	mask = policy->shared_type == CPUFREQ_SHARED_TYPE_ANY ?
 441		cpumask_of(policy->cpu) : policy->cpus;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 442
 443	drv_write(data, mask, perf->states[next_perf_state].control);
 444
 445	if (acpi_pstate_strict) {
 446		if (!check_freqs(policy, mask,
 447				 policy->freq_table[index].frequency)) {
 448			pr_debug("%s (%d)\n", __func__, policy->cpu);
 449			result = -EAGAIN;
 
 450		}
 451	}
 452
 453	if (!result)
 454		perf->state = next_perf_state;
 
 
 
 455
 
 456	return result;
 457}
 458
 459static unsigned int acpi_cpufreq_fast_switch(struct cpufreq_policy *policy,
 460					     unsigned int target_freq)
 461{
 462	struct acpi_cpufreq_data *data = policy->driver_data;
 463	struct acpi_processor_performance *perf;
 464	struct cpufreq_frequency_table *entry;
 465	unsigned int next_perf_state, next_freq, index;
 466
 467	/*
 468	 * Find the closest frequency above target_freq.
 469	 */
 470	if (policy->cached_target_freq == target_freq)
 471		index = policy->cached_resolved_idx;
 472	else
 473		index = cpufreq_table_find_index_dl(policy, target_freq);
 474
 475	entry = &policy->freq_table[index];
 476	next_freq = entry->frequency;
 477	next_perf_state = entry->driver_data;
 478
 479	perf = to_perf_data(data);
 480	if (perf->state == next_perf_state) {
 481		if (unlikely(data->resume))
 482			data->resume = 0;
 483		else
 484			return next_freq;
 485	}
 486
 487	data->cpu_freq_write(&perf->control_register,
 488			     perf->states[next_perf_state].control);
 489	perf->state = next_perf_state;
 490	return next_freq;
 491}
 492
 493static unsigned long
 494acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
 495{
 496	struct acpi_processor_performance *perf;
 497
 498	perf = to_perf_data(data);
 499	if (cpu_khz) {
 500		/* search the closest match to cpu_khz */
 501		unsigned int i;
 502		unsigned long freq;
 503		unsigned long freqn = perf->states[0].core_frequency * 1000;
 504
 505		for (i = 0; i < (perf->state_count-1); i++) {
 506			freq = freqn;
 507			freqn = perf->states[i+1].core_frequency * 1000;
 508			if ((2 * cpu_khz) > (freqn + freq)) {
 509				perf->state = i;
 510				return freq;
 511			}
 512		}
 513		perf->state = perf->state_count-1;
 514		return freqn;
 515	} else {
 516		/* assume CPU is at P0... */
 517		perf->state = 0;
 518		return perf->states[0].core_frequency * 1000;
 519	}
 520}
 521
 522static void free_acpi_perf_data(void)
 523{
 524	unsigned int i;
 525
 526	/* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
 527	for_each_possible_cpu(i)
 528		free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
 529				 ->shared_cpu_map);
 530	free_percpu(acpi_perf_data);
 531}
 532
 533static int cpufreq_boost_online(unsigned int cpu)
 534{
 535	/*
 536	 * On the CPU_UP path we simply keep the boost-disable flag
 537	 * in sync with the current global state.
 538	 */
 539	return boost_set_msr(acpi_cpufreq_driver.boost_enabled);
 540}
 541
 542static int cpufreq_boost_down_prep(unsigned int cpu)
 543{
 544	/*
 545	 * Clear the boost-disable bit on the CPU_DOWN path so that
 546	 * this cpu cannot block the remaining ones from boosting.
 547	 */
 548	return boost_set_msr(1);
 549}
 550
 551/*
 552 * acpi_cpufreq_early_init - initialize ACPI P-States library
 553 *
 554 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
 555 * in order to determine correct frequency and voltage pairings. We can
 556 * do _PDC and _PSD and find out the processor dependency for the
 557 * actual init that will happen later...
 558 */
 559static int __init acpi_cpufreq_early_init(void)
 560{
 561	unsigned int i;
 562	pr_debug("%s\n", __func__);
 563
 564	acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
 565	if (!acpi_perf_data) {
 566		pr_debug("Memory allocation error for acpi_perf_data.\n");
 567		return -ENOMEM;
 568	}
 569	for_each_possible_cpu(i) {
 570		if (!zalloc_cpumask_var_node(
 571			&per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
 572			GFP_KERNEL, cpu_to_node(i))) {
 573
 574			/* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
 575			free_acpi_perf_data();
 576			return -ENOMEM;
 577		}
 578	}
 579
 580	/* Do initialization in ACPI core */
 581	acpi_processor_preregister_performance(acpi_perf_data);
 582	return 0;
 583}
 584
 585#ifdef CONFIG_SMP
 586/*
 587 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
 588 * or do it in BIOS firmware and won't inform about it to OS. If not
 589 * detected, this has a side effect of making CPU run at a different speed
 590 * than OS intended it to run at. Detect it and handle it cleanly.
 591 */
 592static int bios_with_sw_any_bug;
 593
 594static int sw_any_bug_found(const struct dmi_system_id *d)
 595{
 596	bios_with_sw_any_bug = 1;
 597	return 0;
 598}
 599
 600static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 601	{
 602		.callback = sw_any_bug_found,
 603		.ident = "Supermicro Server X6DLP",
 604		.matches = {
 605			DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
 606			DMI_MATCH(DMI_BIOS_VERSION, "080010"),
 607			DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
 608		},
 609	},
 610	{ }
 611};
 612
 613static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
 614{
 615	/* Intel Xeon Processor 7100 Series Specification Update
 616	 * https://www.intel.com/Assets/PDF/specupdate/314554.pdf
 617	 * AL30: A Machine Check Exception (MCE) Occurring during an
 618	 * Enhanced Intel SpeedStep Technology Ratio Change May Cause
 619	 * Both Processor Cores to Lock Up. */
 620	if (c->x86_vendor == X86_VENDOR_INTEL) {
 621		if ((c->x86 == 15) &&
 622		    (c->x86_model == 6) &&
 623		    (c->x86_stepping == 8)) {
 624			pr_info("Intel(R) Xeon(R) 7100 Errata AL30, processors may lock up on frequency changes: disabling acpi-cpufreq\n");
 
 
 
 625			return -ENODEV;
 626		    }
 627		}
 628	return 0;
 629}
 630#endif
 631
 632#ifdef CONFIG_ACPI_CPPC_LIB
 633static u64 get_max_boost_ratio(unsigned int cpu)
 634{
 635	struct cppc_perf_caps perf_caps;
 636	u64 highest_perf, nominal_perf;
 637	int ret;
 638
 639	if (acpi_pstate_strict)
 640		return 0;
 641
 642	ret = cppc_get_perf_caps(cpu, &perf_caps);
 643	if (ret) {
 644		pr_debug("CPU%d: Unable to get performance capabilities (%d)\n",
 645			 cpu, ret);
 646		return 0;
 647	}
 648
 649	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
 650		highest_perf = amd_get_highest_perf();
 651	else
 652		highest_perf = perf_caps.highest_perf;
 653
 654	nominal_perf = perf_caps.nominal_perf;
 655
 656	if (!highest_perf || !nominal_perf) {
 657		pr_debug("CPU%d: highest or nominal performance missing\n", cpu);
 658		return 0;
 659	}
 660
 661	if (highest_perf < nominal_perf) {
 662		pr_debug("CPU%d: nominal performance above highest\n", cpu);
 663		return 0;
 664	}
 665
 666	return div_u64(highest_perf << SCHED_CAPACITY_SHIFT, nominal_perf);
 667}
 668#else
 669static inline u64 get_max_boost_ratio(unsigned int cpu) { return 0; }
 670#endif
 671
 672static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
 673{
 674	struct cpufreq_frequency_table *freq_table;
 675	struct acpi_processor_performance *perf;
 
 676	struct acpi_cpufreq_data *data;
 677	unsigned int cpu = policy->cpu;
 678	struct cpuinfo_x86 *c = &cpu_data(cpu);
 679	unsigned int valid_states = 0;
 680	unsigned int result = 0;
 681	u64 max_boost_ratio;
 682	unsigned int i;
 683#ifdef CONFIG_SMP
 684	static int blacklisted;
 685#endif
 686
 687	pr_debug("%s\n", __func__);
 688
 689#ifdef CONFIG_SMP
 690	if (blacklisted)
 691		return blacklisted;
 692	blacklisted = acpi_cpufreq_blacklist(c);
 693	if (blacklisted)
 694		return blacklisted;
 695#endif
 696
 697	data = kzalloc(sizeof(*data), GFP_KERNEL);
 698	if (!data)
 699		return -ENOMEM;
 700
 701	if (!zalloc_cpumask_var(&data->freqdomain_cpus, GFP_KERNEL)) {
 702		result = -ENOMEM;
 703		goto err_free;
 704	}
 705
 706	perf = per_cpu_ptr(acpi_perf_data, cpu);
 707	data->acpi_perf_cpu = cpu;
 708	policy->driver_data = data;
 709
 710	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC))
 711		acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
 712
 713	result = acpi_processor_register_performance(perf, cpu);
 714	if (result)
 715		goto err_free_mask;
 716
 
 717	policy->shared_type = perf->shared_type;
 718
 719	/*
 720	 * Will let policy->cpus know about dependency only when software
 721	 * coordination is required.
 722	 */
 723	if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
 724	    policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
 725		cpumask_copy(policy->cpus, perf->shared_cpu_map);
 726	}
 727	cpumask_copy(data->freqdomain_cpus, perf->shared_cpu_map);
 728
 729#ifdef CONFIG_SMP
 730	dmi_check_system(sw_any_bug_dmi_table);
 731	if (bios_with_sw_any_bug && !policy_is_shared(policy)) {
 732		policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
 733		cpumask_copy(policy->cpus, topology_core_cpumask(cpu));
 734	}
 735
 736	if (check_amd_hwpstate_cpu(cpu) && boot_cpu_data.x86 < 0x19 &&
 737	    !acpi_pstate_strict) {
 738		cpumask_clear(policy->cpus);
 739		cpumask_set_cpu(cpu, policy->cpus);
 740		cpumask_copy(data->freqdomain_cpus,
 741			     topology_sibling_cpumask(cpu));
 742		policy->shared_type = CPUFREQ_SHARED_TYPE_HW;
 743		pr_info_once("overriding BIOS provided _PSD data\n");
 744	}
 745#endif
 746
 747	/* capability check */
 748	if (perf->state_count <= 1) {
 749		pr_debug("No P-States\n");
 750		result = -ENODEV;
 751		goto err_unreg;
 752	}
 753
 754	if (perf->control_register.space_id != perf->status_register.space_id) {
 755		result = -ENODEV;
 756		goto err_unreg;
 757	}
 758
 759	switch (perf->control_register.space_id) {
 760	case ACPI_ADR_SPACE_SYSTEM_IO:
 761		if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 762		    boot_cpu_data.x86 == 0xf) {
 763			pr_debug("AMD K8 systems must use native drivers.\n");
 764			result = -ENODEV;
 765			goto err_unreg;
 766		}
 767		pr_debug("SYSTEM IO addr space\n");
 768		data->cpu_feature = SYSTEM_IO_CAPABLE;
 769		data->cpu_freq_read = cpu_freq_read_io;
 770		data->cpu_freq_write = cpu_freq_write_io;
 771		break;
 772	case ACPI_ADR_SPACE_FIXED_HARDWARE:
 773		pr_debug("HARDWARE addr space\n");
 774		if (check_est_cpu(cpu)) {
 775			data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
 776			data->cpu_freq_read = cpu_freq_read_intel;
 777			data->cpu_freq_write = cpu_freq_write_intel;
 778			break;
 779		}
 780		if (check_amd_hwpstate_cpu(cpu)) {
 781			data->cpu_feature = SYSTEM_AMD_MSR_CAPABLE;
 782			data->cpu_freq_read = cpu_freq_read_amd;
 783			data->cpu_freq_write = cpu_freq_write_amd;
 784			break;
 785		}
 786		result = -ENODEV;
 787		goto err_unreg;
 788	default:
 789		pr_debug("Unknown addr space %d\n",
 790			(u32) (perf->control_register.space_id));
 791		result = -ENODEV;
 792		goto err_unreg;
 793	}
 794
 795	freq_table = kcalloc(perf->state_count + 1, sizeof(*freq_table),
 796			     GFP_KERNEL);
 797	if (!freq_table) {
 798		result = -ENOMEM;
 799		goto err_unreg;
 800	}
 801
 802	/* detect transition latency */
 803	policy->cpuinfo.transition_latency = 0;
 804	for (i = 0; i < perf->state_count; i++) {
 805		if ((perf->states[i].transition_latency * 1000) >
 806		    policy->cpuinfo.transition_latency)
 807			policy->cpuinfo.transition_latency =
 808			    perf->states[i].transition_latency * 1000;
 809	}
 810
 811	/* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
 812	if (perf->control_register.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE &&
 813	    policy->cpuinfo.transition_latency > 20 * 1000) {
 814		policy->cpuinfo.transition_latency = 20 * 1000;
 815		pr_info_once("P-state transition latency capped at 20 uS\n");
 
 816	}
 817
 818	/* table init */
 819	for (i = 0; i < perf->state_count; i++) {
 820		if (i > 0 && perf->states[i].core_frequency >=
 821		    freq_table[valid_states-1].frequency / 1000)
 822			continue;
 823
 824		freq_table[valid_states].driver_data = i;
 825		freq_table[valid_states].frequency =
 826		    perf->states[i].core_frequency * 1000;
 827		valid_states++;
 828	}
 829	freq_table[valid_states].frequency = CPUFREQ_TABLE_END;
 
 830
 831	max_boost_ratio = get_max_boost_ratio(cpu);
 832	if (max_boost_ratio) {
 833		unsigned int freq = freq_table[0].frequency;
 834
 835		/*
 836		 * Because the loop above sorts the freq_table entries in the
 837		 * descending order, freq is the maximum frequency in the table.
 838		 * Assume that it corresponds to the CPPC nominal frequency and
 839		 * use it to set cpuinfo.max_freq.
 840		 */
 841		policy->cpuinfo.max_freq = freq * max_boost_ratio >> SCHED_CAPACITY_SHIFT;
 842	} else {
 843		/*
 844		 * If the maximum "boost" frequency is unknown, ask the arch
 845		 * scale-invariance code to use the "nominal" performance for
 846		 * CPU utilization scaling so as to prevent the schedutil
 847		 * governor from selecting inadequate CPU frequencies.
 848		 */
 849		arch_set_max_freq_ratio(true);
 850	}
 851
 852	policy->freq_table = freq_table;
 853	perf->state = 0;
 854
 855	switch (perf->control_register.space_id) {
 856	case ACPI_ADR_SPACE_SYSTEM_IO:
 857		/*
 858		 * The core will not set policy->cur, because
 859		 * cpufreq_driver->get is NULL, so we need to set it here.
 860		 * However, we have to guess it, because the current speed is
 861		 * unknown and not detectable via IO ports.
 862		 */
 863		policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
 864		break;
 865	case ACPI_ADR_SPACE_FIXED_HARDWARE:
 866		acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
 
 867		break;
 868	default:
 869		break;
 870	}
 871
 872	/* notify BIOS that we exist */
 873	acpi_processor_notify_smm(THIS_MODULE);
 874
 
 
 
 
 875	pr_debug("CPU%u - ACPI performance management activated.\n", cpu);
 876	for (i = 0; i < perf->state_count; i++)
 877		pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
 878			(i == perf->state ? '*' : ' '), i,
 879			(u32) perf->states[i].core_frequency,
 880			(u32) perf->states[i].power,
 881			(u32) perf->states[i].transition_latency);
 882
 
 
 883	/*
 884	 * the first call to ->target() should result in us actually
 885	 * writing something to the appropriate registers.
 886	 */
 887	data->resume = 1;
 888
 889	policy->fast_switch_possible = !acpi_pstate_strict &&
 890		!(policy_is_shared(policy) && policy->shared_type != CPUFREQ_SHARED_TYPE_ANY);
 891
 892	return result;
 893
 
 
 894err_unreg:
 895	acpi_processor_unregister_performance(cpu);
 896err_free_mask:
 897	free_cpumask_var(data->freqdomain_cpus);
 898err_free:
 899	kfree(data);
 900	policy->driver_data = NULL;
 901
 902	return result;
 903}
 904
 905static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
 906{
 907	struct acpi_cpufreq_data *data = policy->driver_data;
 908
 909	pr_debug("%s\n", __func__);
 910
 911	policy->fast_switch_possible = false;
 912	policy->driver_data = NULL;
 913	acpi_processor_unregister_performance(data->acpi_perf_cpu);
 914	free_cpumask_var(data->freqdomain_cpus);
 915	kfree(policy->freq_table);
 916	kfree(data);
 
 
 917
 918	return 0;
 919}
 920
 921static void acpi_cpufreq_cpu_ready(struct cpufreq_policy *policy)
 922{
 923	struct acpi_processor_performance *perf = per_cpu_ptr(acpi_perf_data,
 924							      policy->cpu);
 925	unsigned int freq = policy->freq_table[0].frequency;
 926
 927	if (perf->states[0].core_frequency * 1000 != freq)
 928		pr_warn(FW_WARN "P-state 0 is not max freq\n");
 929}
 930
 931static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
 932{
 933	struct acpi_cpufreq_data *data = policy->driver_data;
 934
 935	pr_debug("%s\n", __func__);
 936
 937	data->resume = 1;
 938
 939	return 0;
 940}
 941
 942static struct freq_attr *acpi_cpufreq_attr[] = {
 943	&cpufreq_freq_attr_scaling_available_freqs,
 944	&freqdomain_cpus,
 945#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
 946	&cpb,
 947#endif
 948	NULL,
 949};
 950
 951static struct cpufreq_driver acpi_cpufreq_driver = {
 952	.verify		= cpufreq_generic_frequency_table_verify,
 953	.target_index	= acpi_cpufreq_target,
 954	.fast_switch	= acpi_cpufreq_fast_switch,
 955	.bios_limit	= acpi_processor_get_bios_limit,
 956	.init		= acpi_cpufreq_cpu_init,
 957	.exit		= acpi_cpufreq_cpu_exit,
 958	.ready		= acpi_cpufreq_cpu_ready,
 959	.resume		= acpi_cpufreq_resume,
 960	.name		= "acpi-cpufreq",
 
 961	.attr		= acpi_cpufreq_attr,
 962};
 963
 964static enum cpuhp_state acpi_cpufreq_online;
 965
 966static void __init acpi_cpufreq_boost_init(void)
 967{
 968	int ret;
 969
 970	if (!(boot_cpu_has(X86_FEATURE_CPB) || boot_cpu_has(X86_FEATURE_IDA))) {
 971		pr_debug("Boost capabilities not present in the processor\n");
 972		return;
 973	}
 974
 975	acpi_cpufreq_driver.set_boost = set_boost;
 976	acpi_cpufreq_driver.boost_enabled = boost_state(0);
 977
 978	/*
 979	 * This calls the online callback on all online cpu and forces all
 980	 * MSRs to the same value.
 981	 */
 982	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "cpufreq/acpi:online",
 983				cpufreq_boost_online, cpufreq_boost_down_prep);
 984	if (ret < 0) {
 985		pr_err("acpi_cpufreq: failed to register hotplug callbacks\n");
 986		return;
 987	}
 988	acpi_cpufreq_online = ret;
 989}
 990
 991static void acpi_cpufreq_boost_exit(void)
 992{
 993	if (acpi_cpufreq_online > 0)
 994		cpuhp_remove_state_nocalls(acpi_cpufreq_online);
 995}
 996
 997static int __init acpi_cpufreq_init(void)
 998{
 999	int ret;
1000
1001	if (acpi_disabled)
1002		return -ENODEV;
1003
1004	/* don't keep reloading if cpufreq_driver exists */
1005	if (cpufreq_get_current_driver())
1006		return -EEXIST;
1007
1008	pr_debug("%s\n", __func__);
1009
1010	ret = acpi_cpufreq_early_init();
1011	if (ret)
1012		return ret;
1013
1014#ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
1015	/* this is a sysfs file with a strange name and an even stranger
1016	 * semantic - per CPU instantiation, but system global effect.
1017	 * Lets enable it only on AMD CPUs for compatibility reasons and
1018	 * only if configured. This is considered legacy code, which
1019	 * will probably be removed at some point in the future.
1020	 */
1021	if (!check_amd_hwpstate_cpu(0)) {
1022		struct freq_attr **attr;
1023
1024		pr_debug("CPB unsupported, do not expose it\n");
1025
1026		for (attr = acpi_cpufreq_attr; *attr; attr++)
1027			if (*attr == &cpb) {
1028				*attr = NULL;
1029				break;
1030			}
1031	}
1032#endif
1033	acpi_cpufreq_boost_init();
1034
1035	ret = cpufreq_register_driver(&acpi_cpufreq_driver);
1036	if (ret) {
1037		free_acpi_perf_data();
1038		acpi_cpufreq_boost_exit();
1039	}
1040	return ret;
1041}
1042
1043static void __exit acpi_cpufreq_exit(void)
1044{
1045	pr_debug("%s\n", __func__);
1046
1047	acpi_cpufreq_boost_exit();
1048
1049	cpufreq_unregister_driver(&acpi_cpufreq_driver);
1050
1051	free_acpi_perf_data();
1052}
1053
1054module_param(acpi_pstate_strict, uint, 0644);
1055MODULE_PARM_DESC(acpi_pstate_strict,
1056	"value 0 or non-zero. non-zero -> strict ACPI checks are "
1057	"performed during frequency changes.");
1058
1059late_initcall(acpi_cpufreq_init);
1060module_exit(acpi_cpufreq_exit);
1061
1062static const struct x86_cpu_id __maybe_unused acpi_cpufreq_ids[] = {
1063	X86_MATCH_FEATURE(X86_FEATURE_ACPI, NULL),
1064	X86_MATCH_FEATURE(X86_FEATURE_HW_PSTATE, NULL),
1065	{}
1066};
1067MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
1068
1069static const struct acpi_device_id __maybe_unused processor_device_ids[] = {
1070	{ACPI_PROCESSOR_OBJECT_HID, },
1071	{ACPI_PROCESSOR_DEVICE_HID, },
1072	{},
1073};
1074MODULE_DEVICE_TABLE(acpi, processor_device_ids);
1075
1076MODULE_ALIAS("acpi");