2 * acpi-cpufreq.c - ACPI Processor P-States Driver ($Revision: 1.4 $)
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>
9 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
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.
25 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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/sched.h> /* current */
36 #include <linux/dmi.h>
38 #include <linux/acpi.h>
39 #include <acpi/processor.h>
43 #include <asm/processor.h>
44 #include <asm/cpufeature.h>
45 #include <asm/delay.h>
46 #include <asm/uaccess.h>
48 #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "acpi-cpufreq", msg)
50 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
51 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
52 MODULE_LICENSE("GPL");
55 UNDEFINED_CAPABLE = 0,
56 SYSTEM_INTEL_MSR_CAPABLE,
60 #define INTEL_MSR_RANGE (0xffff)
62 struct acpi_cpufreq_data {
63 struct acpi_processor_performance *acpi_data;
64 struct cpufreq_frequency_table *freq_table;
66 unsigned int cpu_feature;
69 static struct acpi_cpufreq_data *drv_data[NR_CPUS];
70 static struct acpi_processor_performance *acpi_perf_data[NR_CPUS];
72 static struct cpufreq_driver acpi_cpufreq_driver;
74 static unsigned int acpi_pstate_strict;
76 static int check_est_cpu(unsigned int cpuid)
78 struct cpuinfo_x86 *cpu = &cpu_data[cpuid];
80 if (cpu->x86_vendor != X86_VENDOR_INTEL ||
81 !cpu_has(cpu, X86_FEATURE_EST))
87 static unsigned extract_io(u32 value, struct acpi_cpufreq_data *data)
89 struct acpi_processor_performance *perf;
92 perf = data->acpi_data;
94 for (i = 0; i < perf->state_count; i++) {
95 if (value == perf->states[i].status)
96 return data->freq_table[i].frequency;
101 static unsigned extract_msr(u32 msr, struct acpi_cpufreq_data *data)
104 struct acpi_processor_performance *perf;
106 msr &= INTEL_MSR_RANGE;
107 perf = data->acpi_data;
109 for (i = 0; data->freq_table[i].frequency != CPUFREQ_TABLE_END; i++) {
110 if (msr == perf->states[data->freq_table[i].index].status)
111 return data->freq_table[i].frequency;
113 return data->freq_table[0].frequency;
116 static unsigned extract_freq(u32 val, struct acpi_cpufreq_data *data)
118 switch (data->cpu_feature) {
119 case SYSTEM_INTEL_MSR_CAPABLE:
120 return extract_msr(val, data);
121 case SYSTEM_IO_CAPABLE:
122 return extract_io(val, data);
128 static void wrport(u16 port, u8 bit_width, u32 value)
130 if (bit_width <= 8) {
132 } else if (bit_width <= 16) {
134 } else if (bit_width <= 32) {
139 static void rdport(u16 port, u8 bit_width, u32 * ret)
142 if (bit_width <= 8) {
144 } else if (bit_width <= 16) {
146 } else if (bit_width <= 32) {
172 static void do_drv_read(struct drv_cmd *cmd)
177 case SYSTEM_INTEL_MSR_CAPABLE:
178 rdmsr(cmd->addr.msr.reg, cmd->val, h);
180 case SYSTEM_IO_CAPABLE:
181 rdport(cmd->addr.io.port, cmd->addr.io.bit_width, &cmd->val);
188 static void do_drv_write(struct drv_cmd *cmd)
193 case SYSTEM_INTEL_MSR_CAPABLE:
194 wrmsr(cmd->addr.msr.reg, cmd->val, h);
196 case SYSTEM_IO_CAPABLE:
197 wrport(cmd->addr.io.port, cmd->addr.io.bit_width, cmd->val);
204 static inline void drv_read(struct drv_cmd *cmd)
206 cpumask_t saved_mask = current->cpus_allowed;
209 set_cpus_allowed(current, cmd->mask);
211 set_cpus_allowed(current, saved_mask);
215 static void drv_write(struct drv_cmd *cmd)
217 cpumask_t saved_mask = current->cpus_allowed;
220 for_each_cpu_mask(i, cmd->mask) {
221 set_cpus_allowed(current, cpumask_of_cpu(i));
225 set_cpus_allowed(current, saved_mask);
229 static u32 get_cur_val(cpumask_t mask)
231 struct acpi_processor_performance *perf;
234 if (unlikely(cpus_empty(mask)))
237 switch (drv_data[first_cpu(mask)]->cpu_feature) {
238 case SYSTEM_INTEL_MSR_CAPABLE:
239 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
240 cmd.addr.msr.reg = MSR_IA32_PERF_STATUS;
242 case SYSTEM_IO_CAPABLE:
243 cmd.type = SYSTEM_IO_CAPABLE;
244 perf = drv_data[first_cpu(mask)]->acpi_data;
245 cmd.addr.io.port = perf->control_register.address;
246 cmd.addr.io.bit_width = perf->control_register.bit_width;
256 dprintk("get_cur_val = %u\n", cmd.val);
261 static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
263 struct acpi_cpufreq_data *data = drv_data[cpu];
266 dprintk("get_cur_freq_on_cpu (%d)\n", cpu);
268 if (unlikely(data == NULL ||
269 data->acpi_data == NULL || data->freq_table == NULL)) {
273 freq = extract_freq(get_cur_val(cpumask_of_cpu(cpu)), data);
274 dprintk("cur freq = %u\n", freq);
279 static unsigned int check_freqs(cpumask_t mask, unsigned int freq,
280 struct acpi_cpufreq_data *data)
282 unsigned int cur_freq;
285 for (i = 0; i < 100; i++) {
286 cur_freq = extract_freq(get_cur_val(mask), data);
287 if (cur_freq == freq)
294 static int acpi_cpufreq_target(struct cpufreq_policy *policy,
295 unsigned int target_freq, unsigned int relation)
297 struct acpi_cpufreq_data *data = drv_data[policy->cpu];
298 struct acpi_processor_performance *perf;
299 struct cpufreq_freqs freqs;
300 cpumask_t online_policy_cpus;
303 unsigned int next_state = 0;
304 unsigned int next_perf_state = 0;
308 dprintk("acpi_cpufreq_target %d (%d)\n", target_freq, policy->cpu);
310 if (unlikely(data == NULL ||
311 data->acpi_data == NULL || data->freq_table == NULL)) {
315 perf = data->acpi_data;
316 result = cpufreq_frequency_table_target(policy,
319 relation, &next_state);
320 if (unlikely(result))
323 #ifdef CONFIG_HOTPLUG_CPU
324 /* cpufreq holds the hotplug lock, so we are safe from here on */
325 cpus_and(online_policy_cpus, cpu_online_map, policy->cpus);
327 online_policy_cpus = policy->cpus;
330 next_perf_state = data->freq_table[next_state].index;
331 if (perf->state == next_perf_state) {
332 if (unlikely(data->resume)) {
333 dprintk("Called after resume, resetting to P%d\n",
337 dprintk("Already at target state (P%d)\n",
343 switch (data->cpu_feature) {
344 case SYSTEM_INTEL_MSR_CAPABLE:
345 cmd.type = SYSTEM_INTEL_MSR_CAPABLE;
346 cmd.addr.msr.reg = MSR_IA32_PERF_CTL;
348 (u32) perf->states[next_perf_state].
349 control & INTEL_MSR_RANGE;
350 cmd.val = (cmd.val & ~INTEL_MSR_RANGE) | msr;
352 case SYSTEM_IO_CAPABLE:
353 cmd.type = SYSTEM_IO_CAPABLE;
354 cmd.addr.io.port = perf->control_register.address;
355 cmd.addr.io.bit_width = perf->control_register.bit_width;
356 cmd.val = (u32) perf->states[next_perf_state].control;
362 cpus_clear(cmd.mask);
364 if (policy->shared_type != CPUFREQ_SHARED_TYPE_ANY)
365 cmd.mask = online_policy_cpus;
367 cpu_set(policy->cpu, cmd.mask);
369 freqs.old = data->freq_table[perf->state].frequency;
370 freqs.new = data->freq_table[next_perf_state].frequency;
371 for_each_cpu_mask(i, cmd.mask) {
373 cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
378 if (acpi_pstate_strict) {
379 if (!check_freqs(cmd.mask, freqs.new, data)) {
380 dprintk("acpi_cpufreq_target failed (%d)\n",
386 for_each_cpu_mask(i, cmd.mask) {
388 cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
390 perf->state = next_perf_state;
395 static int acpi_cpufreq_verify(struct cpufreq_policy *policy)
397 struct acpi_cpufreq_data *data = drv_data[policy->cpu];
399 dprintk("acpi_cpufreq_verify\n");
401 return cpufreq_frequency_table_verify(policy, data->freq_table);
405 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data *data, unsigned int cpu)
407 struct acpi_processor_performance *perf = data->acpi_data;
410 /* search the closest match to cpu_khz */
413 unsigned long freqn = perf->states[0].core_frequency * 1000;
415 for (i = 0; i < (perf->state_count - 1); i++) {
417 freqn = perf->states[i + 1].core_frequency * 1000;
418 if ((2 * cpu_khz) > (freqn + freq)) {
423 perf->state = perf->state_count - 1;
426 /* assume CPU is at P0... */
428 return perf->states[0].core_frequency * 1000;
433 * acpi_cpufreq_early_init - initialize ACPI P-States library
435 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
436 * in order to determine correct frequency and voltage pairings. We can
437 * do _PDC and _PSD and find out the processor dependency for the
438 * actual init that will happen later...
440 static int acpi_cpufreq_early_init(void)
442 struct acpi_processor_performance *data;
446 dprintk("acpi_cpufreq_early_init\n");
448 for_each_possible_cpu(i) {
449 data = kzalloc(sizeof(struct acpi_processor_performance),
452 for_each_cpu_mask(j, covered) {
453 kfree(acpi_perf_data[j]);
454 acpi_perf_data[j] = NULL;
458 acpi_perf_data[i] = data;
462 /* Do initialization in ACPI core */
463 acpi_processor_preregister_performance(acpi_perf_data);
468 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
469 * or do it in BIOS firmware and won't inform about it to OS. If not
470 * detected, this has a side effect of making CPU run at a different speed
471 * than OS intended it to run at. Detect it and handle it cleanly.
473 static int bios_with_sw_any_bug;
475 static int sw_any_bug_found(struct dmi_system_id *d)
477 bios_with_sw_any_bug = 1;
481 static struct dmi_system_id sw_any_bug_dmi_table[] = {
483 .callback = sw_any_bug_found,
484 .ident = "Supermicro Server X6DLP",
486 DMI_MATCH(DMI_SYS_VENDOR, "Supermicro"),
487 DMI_MATCH(DMI_BIOS_VERSION, "080010"),
488 DMI_MATCH(DMI_PRODUCT_NAME, "X6DLP"),
494 static int acpi_cpufreq_cpu_init(struct cpufreq_policy *policy)
497 unsigned int valid_states = 0;
498 unsigned int cpu = policy->cpu;
499 struct acpi_cpufreq_data *data;
501 unsigned int result = 0;
502 struct cpuinfo_x86 *c = &cpu_data[policy->cpu];
503 struct acpi_processor_performance *perf;
505 dprintk("acpi_cpufreq_cpu_init\n");
507 if (!acpi_perf_data[cpu])
510 data = kzalloc(sizeof(struct acpi_cpufreq_data), GFP_KERNEL);
514 data->acpi_data = acpi_perf_data[cpu];
515 drv_data[cpu] = data;
517 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
518 acpi_cpufreq_driver.flags |= CPUFREQ_CONST_LOOPS;
521 result = acpi_processor_register_performance(data->acpi_data, cpu);
525 perf = data->acpi_data;
526 policy->shared_type = perf->shared_type;
528 * Will let policy->cpus know about dependency only when software
529 * coordination is required.
531 if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL ||
532 policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
533 policy->cpus = perf->shared_cpu_map;
537 dmi_check_system(sw_any_bug_dmi_table);
538 if (bios_with_sw_any_bug && cpus_weight(policy->cpus) == 1) {
539 policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
540 policy->cpus = cpu_core_map[cpu];
544 /* capability check */
545 if (perf->state_count <= 1) {
546 dprintk("No P-States\n");
551 if (perf->control_register.space_id != perf->status_register.space_id) {
556 switch (perf->control_register.space_id) {
557 case ACPI_ADR_SPACE_SYSTEM_IO:
558 dprintk("SYSTEM IO addr space\n");
559 data->cpu_feature = SYSTEM_IO_CAPABLE;
561 case ACPI_ADR_SPACE_FIXED_HARDWARE:
562 dprintk("HARDWARE addr space\n");
563 if (!check_est_cpu(cpu)) {
567 data->cpu_feature = SYSTEM_INTEL_MSR_CAPABLE;
570 dprintk("Unknown addr space %d\n",
571 (u32) (perf->control_register.space_id));
577 kmalloc(sizeof(struct cpufreq_frequency_table) *
578 (perf->state_count + 1), GFP_KERNEL);
579 if (!data->freq_table) {
584 /* detect transition latency */
585 policy->cpuinfo.transition_latency = 0;
586 for (i = 0; i < perf->state_count; i++) {
587 if ((perf->states[i].transition_latency * 1000) >
588 policy->cpuinfo.transition_latency)
589 policy->cpuinfo.transition_latency =
590 perf->states[i].transition_latency * 1000;
592 policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
595 for (i = 0; i < perf->state_count; i++) {
596 if (i > 0 && perf->states[i].core_frequency ==
597 perf->states[i - 1].core_frequency)
600 data->freq_table[valid_states].index = i;
601 data->freq_table[valid_states].frequency =
602 perf->states[i].core_frequency * 1000;
605 data->freq_table[perf->state_count].frequency = CPUFREQ_TABLE_END;
607 result = cpufreq_frequency_table_cpuinfo(policy, data->freq_table);
612 switch (data->cpu_feature) {
613 case ACPI_ADR_SPACE_SYSTEM_IO:
614 /* Current speed is unknown and not detectable by IO port */
615 policy->cur = acpi_cpufreq_guess_freq(data, policy->cpu);
617 case ACPI_ADR_SPACE_FIXED_HARDWARE:
618 acpi_cpufreq_driver.get = get_cur_freq_on_cpu;
619 get_cur_freq_on_cpu(cpu);
625 /* notify BIOS that we exist */
626 acpi_processor_notify_smm(THIS_MODULE);
628 dprintk("CPU%u - ACPI performance management activated.\n", cpu);
629 for (i = 0; i < perf->state_count; i++)
630 dprintk(" %cP%d: %d MHz, %d mW, %d uS\n",
631 (i == perf->state ? '*' : ' '), i,
632 (u32) perf->states[i].core_frequency,
633 (u32) perf->states[i].power,
634 (u32) perf->states[i].transition_latency);
636 cpufreq_frequency_table_get_attr(data->freq_table, policy->cpu);
639 * the first call to ->target() should result in us actually
640 * writing something to the appropriate registers.
647 kfree(data->freq_table);
649 acpi_processor_unregister_performance(perf, cpu);
652 drv_data[cpu] = NULL;
657 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy *policy)
659 struct acpi_cpufreq_data *data = drv_data[policy->cpu];
661 dprintk("acpi_cpufreq_cpu_exit\n");
664 cpufreq_frequency_table_put_attr(policy->cpu);
665 drv_data[policy->cpu] = NULL;
666 acpi_processor_unregister_performance(data->acpi_data,
674 static int acpi_cpufreq_resume(struct cpufreq_policy *policy)
676 struct acpi_cpufreq_data *data = drv_data[policy->cpu];
678 dprintk("acpi_cpufreq_resume\n");
685 static struct freq_attr *acpi_cpufreq_attr[] = {
686 &cpufreq_freq_attr_scaling_available_freqs,
690 static struct cpufreq_driver acpi_cpufreq_driver = {
691 .verify = acpi_cpufreq_verify,
692 .target = acpi_cpufreq_target,
693 .init = acpi_cpufreq_cpu_init,
694 .exit = acpi_cpufreq_cpu_exit,
695 .resume = acpi_cpufreq_resume,
696 .name = "acpi-cpufreq",
697 .owner = THIS_MODULE,
698 .attr = acpi_cpufreq_attr,
701 static int __init acpi_cpufreq_init(void)
703 dprintk("acpi_cpufreq_init\n");
705 acpi_cpufreq_early_init();
707 return cpufreq_register_driver(&acpi_cpufreq_driver);
710 static void __exit acpi_cpufreq_exit(void)
713 dprintk("acpi_cpufreq_exit\n");
715 cpufreq_unregister_driver(&acpi_cpufreq_driver);
717 for_each_possible_cpu(i) {
718 kfree(acpi_perf_data[i]);
719 acpi_perf_data[i] = NULL;
724 module_param(acpi_pstate_strict, uint, 0644);
725 MODULE_PARM_DESC(acpi_pstate_strict,
726 "value 0 or non-zero. non-zero -> strict ACPI checks are performed during frequency changes.");
728 late_initcall(acpi_cpufreq_init);
729 module_exit(acpi_cpufreq_exit);
731 MODULE_ALIAS("acpi");