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/dmi.h>
37 #include <linux/acpi.h>
38 #include <acpi/processor.h>
42 #include <asm/processor.h>
43 #include <asm/cpufeature.h>
44 #include <asm/delay.h>
45 #include <asm/uaccess.h>
47 #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "acpi-cpufreq", msg)
49 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
50 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
51 MODULE_LICENSE("GPL");
54 UNDEFINED_CAPABLE
= 0,
55 SYSTEM_INTEL_MSR_CAPABLE
,
59 #define INTEL_MSR_RANGE (0xffff)
60 #define CPUID_6_ECX_APERFMPERF_CAPABILITY (0x1)
62 struct acpi_cpufreq_data
{
63 struct acpi_processor_performance
*acpi_data
;
64 struct cpufreq_frequency_table
*freq_table
;
65 unsigned int max_freq
;
67 unsigned int cpu_feature
;
70 static struct acpi_cpufreq_data
*drv_data
[NR_CPUS
];
71 static struct acpi_processor_performance
*acpi_perf_data
[NR_CPUS
];
73 static struct cpufreq_driver acpi_cpufreq_driver
;
75 static unsigned int acpi_pstate_strict
;
77 static int check_est_cpu(unsigned int cpuid
)
79 struct cpuinfo_x86
*cpu
= &cpu_data
[cpuid
];
81 if (cpu
->x86_vendor
!= X86_VENDOR_INTEL
||
82 !cpu_has(cpu
, X86_FEATURE_EST
))
88 static unsigned extract_io(u32 value
, struct acpi_cpufreq_data
*data
)
90 struct acpi_processor_performance
*perf
;
93 perf
= data
->acpi_data
;
95 for (i
=0; i
<perf
->state_count
; i
++) {
96 if (value
== perf
->states
[i
].status
)
97 return data
->freq_table
[i
].frequency
;
102 static unsigned extract_msr(u32 msr
, struct acpi_cpufreq_data
*data
)
105 struct acpi_processor_performance
*perf
;
107 msr
&= INTEL_MSR_RANGE
;
108 perf
= data
->acpi_data
;
110 for (i
=0; data
->freq_table
[i
].frequency
!= CPUFREQ_TABLE_END
; i
++) {
111 if (msr
== perf
->states
[data
->freq_table
[i
].index
].status
)
112 return data
->freq_table
[i
].frequency
;
114 return data
->freq_table
[0].frequency
;
117 static unsigned extract_freq(u32 val
, struct acpi_cpufreq_data
*data
)
119 switch (data
->cpu_feature
) {
120 case SYSTEM_INTEL_MSR_CAPABLE
:
121 return extract_msr(val
, data
);
122 case SYSTEM_IO_CAPABLE
:
123 return extract_io(val
, data
);
150 static void do_drv_read(struct drv_cmd
*cmd
)
155 case SYSTEM_INTEL_MSR_CAPABLE
:
156 rdmsr(cmd
->addr
.msr
.reg
, cmd
->val
, h
);
158 case SYSTEM_IO_CAPABLE
:
159 acpi_os_read_port((acpi_io_address
)cmd
->addr
.io
.port
,
161 (u32
)cmd
->addr
.io
.bit_width
);
168 static void do_drv_write(struct drv_cmd
*cmd
)
173 case SYSTEM_INTEL_MSR_CAPABLE
:
174 wrmsr(cmd
->addr
.msr
.reg
, cmd
->val
, h
);
176 case SYSTEM_IO_CAPABLE
:
177 acpi_os_write_port((acpi_io_address
)cmd
->addr
.io
.port
,
179 (u32
)cmd
->addr
.io
.bit_width
);
186 static void drv_read(struct drv_cmd
*cmd
)
188 cpumask_t saved_mask
= current
->cpus_allowed
;
191 set_cpus_allowed(current
, cmd
->mask
);
193 set_cpus_allowed(current
, saved_mask
);
196 static void drv_write(struct drv_cmd
*cmd
)
198 cpumask_t saved_mask
= current
->cpus_allowed
;
201 for_each_cpu_mask(i
, cmd
->mask
) {
202 set_cpus_allowed(current
, cpumask_of_cpu(i
));
206 set_cpus_allowed(current
, saved_mask
);
210 static u32
get_cur_val(cpumask_t mask
)
212 struct acpi_processor_performance
*perf
;
215 if (unlikely(cpus_empty(mask
)))
218 switch (drv_data
[first_cpu(mask
)]->cpu_feature
) {
219 case SYSTEM_INTEL_MSR_CAPABLE
:
220 cmd
.type
= SYSTEM_INTEL_MSR_CAPABLE
;
221 cmd
.addr
.msr
.reg
= MSR_IA32_PERF_STATUS
;
223 case SYSTEM_IO_CAPABLE
:
224 cmd
.type
= SYSTEM_IO_CAPABLE
;
225 perf
= drv_data
[first_cpu(mask
)]->acpi_data
;
226 cmd
.addr
.io
.port
= perf
->control_register
.address
;
227 cmd
.addr
.io
.bit_width
= perf
->control_register
.bit_width
;
237 dprintk("get_cur_val = %u\n", cmd
.val
);
243 * Return the measured active (C0) frequency on this CPU since last call
246 * Return: Average CPU frequency in terms of max frequency (zero on error)
248 * We use IA32_MPERF and IA32_APERF MSRs to get the measured performance
249 * over a period of time, while CPU is in C0 state.
250 * IA32_MPERF counts at the rate of max advertised frequency
251 * IA32_APERF counts at the rate of actual CPU frequency
252 * Only IA32_APERF/IA32_MPERF ratio is architecturally defined and
253 * no meaning should be associated with absolute values of these MSRs.
255 static unsigned int get_measured_perf(unsigned int cpu
)
263 } aperf_cur
, mperf_cur
;
265 cpumask_t saved_mask
;
266 unsigned int perf_percent
;
269 saved_mask
= current
->cpus_allowed
;
270 set_cpus_allowed(current
, cpumask_of_cpu(cpu
));
271 if (get_cpu() != cpu
) {
272 /* We were not able to run on requested processor */
277 rdmsr(MSR_IA32_APERF
, aperf_cur
.split
.lo
, aperf_cur
.split
.hi
);
278 rdmsr(MSR_IA32_MPERF
, mperf_cur
.split
.lo
, mperf_cur
.split
.hi
);
280 wrmsr(MSR_IA32_APERF
, 0,0);
281 wrmsr(MSR_IA32_MPERF
, 0,0);
285 * We dont want to do 64 bit divide with 32 bit kernel
286 * Get an approximate value. Return failure in case we cannot get
287 * an approximate value.
289 if (unlikely(aperf_cur
.split
.hi
|| mperf_cur
.split
.hi
)) {
293 h
= max_t(u32
, aperf_cur
.split
.hi
, mperf_cur
.split
.hi
);
294 shift_count
= fls(h
);
296 aperf_cur
.whole
>>= shift_count
;
297 mperf_cur
.whole
>>= shift_count
;
300 if (((unsigned long)(-1) / 100) < aperf_cur
.split
.lo
) {
302 aperf_cur
.split
.lo
>>= shift_count
;
303 mperf_cur
.split
.lo
>>= shift_count
;
306 if (aperf_cur
.split
.lo
&& mperf_cur
.split
.lo
)
307 perf_percent
= (aperf_cur
.split
.lo
* 100) / mperf_cur
.split
.lo
;
312 if (unlikely(((unsigned long)(-1) / 100) < aperf_cur
.whole
)) {
314 aperf_cur
.whole
>>= shift_count
;
315 mperf_cur
.whole
>>= shift_count
;
318 if (aperf_cur
.whole
&& mperf_cur
.whole
)
319 perf_percent
= (aperf_cur
.whole
* 100) / mperf_cur
.whole
;
325 retval
= drv_data
[cpu
]->max_freq
* perf_percent
/ 100;
328 set_cpus_allowed(current
, saved_mask
);
330 dprintk("cpu %d: performance percent %d\n", cpu
, perf_percent
);
334 static unsigned int get_cur_freq_on_cpu(unsigned int cpu
)
336 struct acpi_cpufreq_data
*data
= drv_data
[cpu
];
339 dprintk("get_cur_freq_on_cpu (%d)\n", cpu
);
341 if (unlikely(data
== NULL
||
342 data
->acpi_data
== NULL
|| data
->freq_table
== NULL
)) {
346 freq
= extract_freq(get_cur_val(cpumask_of_cpu(cpu
)), data
);
347 dprintk("cur freq = %u\n", freq
);
352 static unsigned int check_freqs(cpumask_t mask
, unsigned int freq
,
353 struct acpi_cpufreq_data
*data
)
355 unsigned int cur_freq
;
358 for (i
=0; i
<100; i
++) {
359 cur_freq
= extract_freq(get_cur_val(mask
), data
);
360 if (cur_freq
== freq
)
367 static int acpi_cpufreq_target(struct cpufreq_policy
*policy
,
368 unsigned int target_freq
, unsigned int relation
)
370 struct acpi_cpufreq_data
*data
= drv_data
[policy
->cpu
];
371 struct acpi_processor_performance
*perf
;
372 struct cpufreq_freqs freqs
;
373 cpumask_t online_policy_cpus
;
376 unsigned int next_state
= 0; /* Index into freq_table */
377 unsigned int next_perf_state
= 0; /* Index into perf table */
381 dprintk("acpi_cpufreq_target %d (%d)\n", target_freq
, policy
->cpu
);
383 if (unlikely(data
== NULL
||
384 data
->acpi_data
== NULL
|| data
->freq_table
== NULL
)) {
388 perf
= data
->acpi_data
;
389 result
= cpufreq_frequency_table_target(policy
,
392 relation
, &next_state
);
393 if (unlikely(result
))
396 #ifdef CONFIG_HOTPLUG_CPU
397 /* cpufreq holds the hotplug lock, so we are safe from here on */
398 cpus_and(online_policy_cpus
, cpu_online_map
, policy
->cpus
);
400 online_policy_cpus
= policy
->cpus
;
403 next_perf_state
= data
->freq_table
[next_state
].index
;
404 if (perf
->state
== next_perf_state
) {
405 if (unlikely(data
->resume
)) {
406 dprintk("Called after resume, resetting to P%d\n",
410 dprintk("Already at target state (P%d)\n",
416 switch (data
->cpu_feature
) {
417 case SYSTEM_INTEL_MSR_CAPABLE
:
418 cmd
.type
= SYSTEM_INTEL_MSR_CAPABLE
;
419 cmd
.addr
.msr
.reg
= MSR_IA32_PERF_CTL
;
421 (u32
) perf
->states
[next_perf_state
].
422 control
& INTEL_MSR_RANGE
;
423 cmd
.val
= get_cur_val(online_policy_cpus
);
424 cmd
.val
= (cmd
.val
& ~INTEL_MSR_RANGE
) | msr
;
426 case SYSTEM_IO_CAPABLE
:
427 cmd
.type
= SYSTEM_IO_CAPABLE
;
428 cmd
.addr
.io
.port
= perf
->control_register
.address
;
429 cmd
.addr
.io
.bit_width
= perf
->control_register
.bit_width
;
430 cmd
.val
= (u32
) perf
->states
[next_perf_state
].control
;
436 cpus_clear(cmd
.mask
);
438 if (policy
->shared_type
!= CPUFREQ_SHARED_TYPE_ANY
)
439 cmd
.mask
= online_policy_cpus
;
441 cpu_set(policy
->cpu
, cmd
.mask
);
443 freqs
.old
= perf
->states
[perf
->state
].core_frequency
* 1000;
444 freqs
.new = data
->freq_table
[next_state
].frequency
;
445 for_each_cpu_mask(i
, cmd
.mask
) {
447 cpufreq_notify_transition(&freqs
, CPUFREQ_PRECHANGE
);
452 if (acpi_pstate_strict
) {
453 if (!check_freqs(cmd
.mask
, freqs
.new, data
)) {
454 dprintk("acpi_cpufreq_target failed (%d)\n",
460 for_each_cpu_mask(i
, cmd
.mask
) {
462 cpufreq_notify_transition(&freqs
, CPUFREQ_POSTCHANGE
);
464 perf
->state
= next_perf_state
;
469 static int acpi_cpufreq_verify(struct cpufreq_policy
*policy
)
471 struct acpi_cpufreq_data
*data
= drv_data
[policy
->cpu
];
473 dprintk("acpi_cpufreq_verify\n");
475 return cpufreq_frequency_table_verify(policy
, data
->freq_table
);
479 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data
*data
, unsigned int cpu
)
481 struct acpi_processor_performance
*perf
= data
->acpi_data
;
484 /* search the closest match to cpu_khz */
487 unsigned long freqn
= perf
->states
[0].core_frequency
* 1000;
489 for (i
=0; i
<(perf
->state_count
-1); i
++) {
491 freqn
= perf
->states
[i
+1].core_frequency
* 1000;
492 if ((2 * cpu_khz
) > (freqn
+ freq
)) {
497 perf
->state
= perf
->state_count
-1;
500 /* assume CPU is at P0... */
502 return perf
->states
[0].core_frequency
* 1000;
507 * acpi_cpufreq_early_init - initialize ACPI P-States library
509 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
510 * in order to determine correct frequency and voltage pairings. We can
511 * do _PDC and _PSD and find out the processor dependency for the
512 * actual init that will happen later...
514 static int acpi_cpufreq_early_init(void)
516 struct acpi_processor_performance
*data
;
520 dprintk("acpi_cpufreq_early_init\n");
522 for_each_possible_cpu(i
) {
523 data
= kzalloc(sizeof(struct acpi_processor_performance
),
526 for_each_cpu_mask(j
, covered
) {
527 kfree(acpi_perf_data
[j
]);
528 acpi_perf_data
[j
] = NULL
;
532 acpi_perf_data
[i
] = data
;
536 /* Do initialization in ACPI core */
537 acpi_processor_preregister_performance(acpi_perf_data
);
543 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
544 * or do it in BIOS firmware and won't inform about it to OS. If not
545 * detected, this has a side effect of making CPU run at a different speed
546 * than OS intended it to run at. Detect it and handle it cleanly.
548 static int bios_with_sw_any_bug
;
550 static int sw_any_bug_found(struct dmi_system_id
*d
)
552 bios_with_sw_any_bug
= 1;
556 static struct dmi_system_id sw_any_bug_dmi_table
[] = {
558 .callback
= sw_any_bug_found
,
559 .ident
= "Supermicro Server X6DLP",
561 DMI_MATCH(DMI_SYS_VENDOR
, "Supermicro"),
562 DMI_MATCH(DMI_BIOS_VERSION
, "080010"),
563 DMI_MATCH(DMI_PRODUCT_NAME
, "X6DLP"),
570 static int acpi_cpufreq_cpu_init(struct cpufreq_policy
*policy
)
573 unsigned int valid_states
= 0;
574 unsigned int cpu
= policy
->cpu
;
575 struct acpi_cpufreq_data
*data
;
576 unsigned int result
= 0;
577 struct cpuinfo_x86
*c
= &cpu_data
[policy
->cpu
];
578 struct acpi_processor_performance
*perf
;
580 dprintk("acpi_cpufreq_cpu_init\n");
582 if (!acpi_perf_data
[cpu
])
585 data
= kzalloc(sizeof(struct acpi_cpufreq_data
), GFP_KERNEL
);
589 data
->acpi_data
= acpi_perf_data
[cpu
];
590 drv_data
[cpu
] = data
;
592 if (cpu_has(c
, X86_FEATURE_CONSTANT_TSC
))
593 acpi_cpufreq_driver
.flags
|= CPUFREQ_CONST_LOOPS
;
595 result
= acpi_processor_register_performance(data
->acpi_data
, cpu
);
599 perf
= data
->acpi_data
;
600 policy
->shared_type
= perf
->shared_type
;
603 * Will let policy->cpus know about dependency only when software
604 * coordination is required.
606 if (policy
->shared_type
== CPUFREQ_SHARED_TYPE_ALL
||
607 policy
->shared_type
== CPUFREQ_SHARED_TYPE_ANY
) {
608 policy
->cpus
= perf
->shared_cpu_map
;
612 dmi_check_system(sw_any_bug_dmi_table
);
613 if (bios_with_sw_any_bug
&& cpus_weight(policy
->cpus
) == 1) {
614 policy
->shared_type
= CPUFREQ_SHARED_TYPE_ALL
;
615 policy
->cpus
= cpu_core_map
[cpu
];
619 /* capability check */
620 if (perf
->state_count
<= 1) {
621 dprintk("No P-States\n");
626 if (perf
->control_register
.space_id
!= perf
->status_register
.space_id
) {
631 switch (perf
->control_register
.space_id
) {
632 case ACPI_ADR_SPACE_SYSTEM_IO
:
633 dprintk("SYSTEM IO addr space\n");
634 data
->cpu_feature
= SYSTEM_IO_CAPABLE
;
636 case ACPI_ADR_SPACE_FIXED_HARDWARE
:
637 dprintk("HARDWARE addr space\n");
638 if (!check_est_cpu(cpu
)) {
642 data
->cpu_feature
= SYSTEM_INTEL_MSR_CAPABLE
;
645 dprintk("Unknown addr space %d\n",
646 (u32
) (perf
->control_register
.space_id
));
651 data
->freq_table
= kmalloc(sizeof(struct cpufreq_frequency_table
) *
652 (perf
->state_count
+1), GFP_KERNEL
);
653 if (!data
->freq_table
) {
658 /* detect transition latency */
659 policy
->cpuinfo
.transition_latency
= 0;
660 for (i
=0; i
<perf
->state_count
; i
++) {
661 if ((perf
->states
[i
].transition_latency
* 1000) >
662 policy
->cpuinfo
.transition_latency
)
663 policy
->cpuinfo
.transition_latency
=
664 perf
->states
[i
].transition_latency
* 1000;
666 policy
->governor
= CPUFREQ_DEFAULT_GOVERNOR
;
668 data
->max_freq
= perf
->states
[0].core_frequency
* 1000;
670 for (i
=0; i
<perf
->state_count
; i
++) {
671 if (i
>0 && perf
->states
[i
].core_frequency
==
672 perf
->states
[i
-1].core_frequency
)
675 data
->freq_table
[valid_states
].index
= i
;
676 data
->freq_table
[valid_states
].frequency
=
677 perf
->states
[i
].core_frequency
* 1000;
680 data
->freq_table
[valid_states
].frequency
= CPUFREQ_TABLE_END
;
683 result
= cpufreq_frequency_table_cpuinfo(policy
, data
->freq_table
);
687 switch (perf
->control_register
.space_id
) {
688 case ACPI_ADR_SPACE_SYSTEM_IO
:
689 /* Current speed is unknown and not detectable by IO port */
690 policy
->cur
= acpi_cpufreq_guess_freq(data
, policy
->cpu
);
692 case ACPI_ADR_SPACE_FIXED_HARDWARE
:
693 acpi_cpufreq_driver
.get
= get_cur_freq_on_cpu
;
694 policy
->cur
= get_cur_freq_on_cpu(cpu
);
700 /* notify BIOS that we exist */
701 acpi_processor_notify_smm(THIS_MODULE
);
703 /* Check for APERF/MPERF support in hardware */
704 if (c
->x86_vendor
== X86_VENDOR_INTEL
&& c
->cpuid_level
>= 6) {
707 if (ecx
& CPUID_6_ECX_APERFMPERF_CAPABILITY
)
708 acpi_cpufreq_driver
.getavg
= get_measured_perf
;
711 dprintk("CPU%u - ACPI performance management activated.\n", cpu
);
712 for (i
= 0; i
< perf
->state_count
; i
++)
713 dprintk(" %cP%d: %d MHz, %d mW, %d uS\n",
714 (i
== perf
->state
? '*' : ' '), i
,
715 (u32
) perf
->states
[i
].core_frequency
,
716 (u32
) perf
->states
[i
].power
,
717 (u32
) perf
->states
[i
].transition_latency
);
719 cpufreq_frequency_table_get_attr(data
->freq_table
, policy
->cpu
);
722 * the first call to ->target() should result in us actually
723 * writing something to the appropriate registers.
730 kfree(data
->freq_table
);
732 acpi_processor_unregister_performance(perf
, cpu
);
735 drv_data
[cpu
] = NULL
;
740 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy
*policy
)
742 struct acpi_cpufreq_data
*data
= drv_data
[policy
->cpu
];
744 dprintk("acpi_cpufreq_cpu_exit\n");
747 cpufreq_frequency_table_put_attr(policy
->cpu
);
748 drv_data
[policy
->cpu
] = NULL
;
749 acpi_processor_unregister_performance(data
->acpi_data
,
757 static int acpi_cpufreq_resume(struct cpufreq_policy
*policy
)
759 struct acpi_cpufreq_data
*data
= drv_data
[policy
->cpu
];
761 dprintk("acpi_cpufreq_resume\n");
768 static struct freq_attr
*acpi_cpufreq_attr
[] = {
769 &cpufreq_freq_attr_scaling_available_freqs
,
773 static struct cpufreq_driver acpi_cpufreq_driver
= {
774 .verify
= acpi_cpufreq_verify
,
775 .target
= acpi_cpufreq_target
,
776 .init
= acpi_cpufreq_cpu_init
,
777 .exit
= acpi_cpufreq_cpu_exit
,
778 .resume
= acpi_cpufreq_resume
,
779 .name
= "acpi-cpufreq",
780 .owner
= THIS_MODULE
,
781 .attr
= acpi_cpufreq_attr
,
784 static int __init
acpi_cpufreq_init(void)
786 dprintk("acpi_cpufreq_init\n");
788 acpi_cpufreq_early_init();
790 return cpufreq_register_driver(&acpi_cpufreq_driver
);
793 static void __exit
acpi_cpufreq_exit(void)
796 dprintk("acpi_cpufreq_exit\n");
798 cpufreq_unregister_driver(&acpi_cpufreq_driver
);
800 for_each_possible_cpu(i
) {
801 kfree(acpi_perf_data
[i
]);
802 acpi_perf_data
[i
] = NULL
;
807 module_param(acpi_pstate_strict
, uint
, 0644);
808 MODULE_PARM_DESC(acpi_pstate_strict
,
809 "value 0 or non-zero. non-zero -> strict ACPI checks are "
810 "performed during frequency changes.");
812 late_initcall(acpi_cpufreq_init
);
813 module_exit(acpi_cpufreq_exit
);
815 MODULE_ALIAS("acpi");