2 * acpi-cpufreq.c - ACPI Processor P-States Driver
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>
36 #include <linux/slab.h>
38 #include <linux/acpi.h>
40 #include <linux/delay.h>
41 #include <linux/uaccess.h>
43 #include <acpi/processor.h>
46 #include <asm/processor.h>
47 #include <asm/cpufeature.h>
49 MODULE_AUTHOR("Paul Diefenbaugh, Dominik Brodowski");
50 MODULE_DESCRIPTION("ACPI Processor P-States Driver");
51 MODULE_LICENSE("GPL");
53 #define PFX "acpi-cpufreq: "
56 UNDEFINED_CAPABLE
= 0,
57 SYSTEM_INTEL_MSR_CAPABLE
,
58 SYSTEM_AMD_MSR_CAPABLE
,
62 #define INTEL_MSR_RANGE (0xffff)
63 #define AMD_MSR_RANGE (0x7)
65 #define MSR_K7_HWCR_CPB_DIS (1ULL << 25)
67 struct acpi_cpufreq_data
{
68 struct acpi_processor_performance
*acpi_data
;
69 struct cpufreq_frequency_table
*freq_table
;
71 unsigned int cpu_feature
;
72 unsigned int acpi_perf_cpu
;
73 cpumask_var_t freqdomain_cpus
;
76 /* acpi_perf_data is a pointer to percpu data. */
77 static struct acpi_processor_performance __percpu
*acpi_perf_data
;
79 static struct cpufreq_driver acpi_cpufreq_driver
;
81 static unsigned int acpi_pstate_strict
;
82 static struct msr __percpu
*msrs
;
84 static bool boost_state(unsigned int cpu
)
89 switch (boot_cpu_data
.x86_vendor
) {
90 case X86_VENDOR_INTEL
:
91 rdmsr_on_cpu(cpu
, MSR_IA32_MISC_ENABLE
, &lo
, &hi
);
92 msr
= lo
| ((u64
)hi
<< 32);
93 return !(msr
& MSR_IA32_MISC_ENABLE_TURBO_DISABLE
);
95 rdmsr_on_cpu(cpu
, MSR_K7_HWCR
, &lo
, &hi
);
96 msr
= lo
| ((u64
)hi
<< 32);
97 return !(msr
& MSR_K7_HWCR_CPB_DIS
);
102 static void boost_set_msrs(bool enable
, const struct cpumask
*cpumask
)
108 switch (boot_cpu_data
.x86_vendor
) {
109 case X86_VENDOR_INTEL
:
110 msr_addr
= MSR_IA32_MISC_ENABLE
;
111 msr_mask
= MSR_IA32_MISC_ENABLE_TURBO_DISABLE
;
114 msr_addr
= MSR_K7_HWCR
;
115 msr_mask
= MSR_K7_HWCR_CPB_DIS
;
121 rdmsr_on_cpus(cpumask
, msr_addr
, msrs
);
123 for_each_cpu(cpu
, cpumask
) {
124 struct msr
*reg
= per_cpu_ptr(msrs
, cpu
);
131 wrmsr_on_cpus(cpumask
, msr_addr
, msrs
);
134 static int _store_boost(int val
)
137 boost_set_msrs(val
, cpu_online_mask
);
139 pr_debug("Core Boosting %sabled.\n", val
? "en" : "dis");
144 static ssize_t
show_freqdomain_cpus(struct cpufreq_policy
*policy
, char *buf
)
146 struct acpi_cpufreq_data
*data
= policy
->driver_data
;
148 return cpufreq_show_cpus(data
->freqdomain_cpus
, buf
);
151 cpufreq_freq_attr_ro(freqdomain_cpus
);
153 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
154 static ssize_t
store_boost(const char *buf
, size_t count
)
157 unsigned long val
= 0;
159 if (!acpi_cpufreq_driver
.boost_supported
)
162 ret
= kstrtoul(buf
, 10, &val
);
163 if (ret
|| (val
> 1))
166 _store_boost((int) val
);
171 static ssize_t
store_cpb(struct cpufreq_policy
*policy
, const char *buf
,
174 return store_boost(buf
, count
);
177 static ssize_t
show_cpb(struct cpufreq_policy
*policy
, char *buf
)
179 return sprintf(buf
, "%u\n", acpi_cpufreq_driver
.boost_enabled
);
182 cpufreq_freq_attr_rw(cpb
);
185 static int check_est_cpu(unsigned int cpuid
)
187 struct cpuinfo_x86
*cpu
= &cpu_data(cpuid
);
189 return cpu_has(cpu
, X86_FEATURE_EST
);
192 static int check_amd_hwpstate_cpu(unsigned int cpuid
)
194 struct cpuinfo_x86
*cpu
= &cpu_data(cpuid
);
196 return cpu_has(cpu
, X86_FEATURE_HW_PSTATE
);
199 static unsigned extract_io(u32 value
, struct acpi_cpufreq_data
*data
)
201 struct acpi_processor_performance
*perf
;
204 perf
= data
->acpi_data
;
206 for (i
= 0; i
< perf
->state_count
; i
++) {
207 if (value
== perf
->states
[i
].status
)
208 return data
->freq_table
[i
].frequency
;
213 static unsigned extract_msr(u32 msr
, struct acpi_cpufreq_data
*data
)
215 struct cpufreq_frequency_table
*pos
;
216 struct acpi_processor_performance
*perf
;
218 if (boot_cpu_data
.x86_vendor
== X86_VENDOR_AMD
)
219 msr
&= AMD_MSR_RANGE
;
221 msr
&= INTEL_MSR_RANGE
;
223 perf
= data
->acpi_data
;
225 cpufreq_for_each_entry(pos
, data
->freq_table
)
226 if (msr
== perf
->states
[pos
->driver_data
].status
)
227 return pos
->frequency
;
228 return data
->freq_table
[0].frequency
;
231 static unsigned extract_freq(u32 val
, struct acpi_cpufreq_data
*data
)
233 switch (data
->cpu_feature
) {
234 case SYSTEM_INTEL_MSR_CAPABLE
:
235 case SYSTEM_AMD_MSR_CAPABLE
:
236 return extract_msr(val
, data
);
237 case SYSTEM_IO_CAPABLE
:
238 return extract_io(val
, data
);
255 const struct cpumask
*mask
;
263 /* Called via smp_call_function_single(), on the target CPU */
264 static void do_drv_read(void *_cmd
)
266 struct drv_cmd
*cmd
= _cmd
;
270 case SYSTEM_INTEL_MSR_CAPABLE
:
271 case SYSTEM_AMD_MSR_CAPABLE
:
272 rdmsr(cmd
->addr
.msr
.reg
, cmd
->val
, h
);
274 case SYSTEM_IO_CAPABLE
:
275 acpi_os_read_port((acpi_io_address
)cmd
->addr
.io
.port
,
277 (u32
)cmd
->addr
.io
.bit_width
);
284 /* Called via smp_call_function_many(), on the target CPUs */
285 static void do_drv_write(void *_cmd
)
287 struct drv_cmd
*cmd
= _cmd
;
291 case SYSTEM_INTEL_MSR_CAPABLE
:
292 rdmsr(cmd
->addr
.msr
.reg
, lo
, hi
);
293 lo
= (lo
& ~INTEL_MSR_RANGE
) | (cmd
->val
& INTEL_MSR_RANGE
);
294 wrmsr(cmd
->addr
.msr
.reg
, lo
, hi
);
296 case SYSTEM_AMD_MSR_CAPABLE
:
297 wrmsr(cmd
->addr
.msr
.reg
, cmd
->val
, 0);
299 case SYSTEM_IO_CAPABLE
:
300 acpi_os_write_port((acpi_io_address
)cmd
->addr
.io
.port
,
302 (u32
)cmd
->addr
.io
.bit_width
);
309 static void drv_read(struct drv_cmd
*cmd
)
314 err
= smp_call_function_any(cmd
->mask
, do_drv_read
, cmd
, 1);
315 WARN_ON_ONCE(err
); /* smp_call_function_any() was buggy? */
318 static void drv_write(struct drv_cmd
*cmd
)
322 this_cpu
= get_cpu();
323 if (cpumask_test_cpu(this_cpu
, cmd
->mask
))
325 smp_call_function_many(cmd
->mask
, do_drv_write
, cmd
, 1);
330 get_cur_val(const struct cpumask
*mask
, struct acpi_cpufreq_data
*data
)
332 struct acpi_processor_performance
*perf
;
335 if (unlikely(cpumask_empty(mask
)))
338 switch (data
->cpu_feature
) {
339 case SYSTEM_INTEL_MSR_CAPABLE
:
340 cmd
.type
= SYSTEM_INTEL_MSR_CAPABLE
;
341 cmd
.addr
.msr
.reg
= MSR_IA32_PERF_CTL
;
343 case SYSTEM_AMD_MSR_CAPABLE
:
344 cmd
.type
= SYSTEM_AMD_MSR_CAPABLE
;
345 cmd
.addr
.msr
.reg
= MSR_AMD_PERF_CTL
;
347 case SYSTEM_IO_CAPABLE
:
348 cmd
.type
= SYSTEM_IO_CAPABLE
;
349 perf
= data
->acpi_data
;
350 cmd
.addr
.io
.port
= perf
->control_register
.address
;
351 cmd
.addr
.io
.bit_width
= perf
->control_register
.bit_width
;
360 pr_debug("get_cur_val = %u\n", cmd
.val
);
365 static unsigned int get_cur_freq_on_cpu(unsigned int cpu
)
367 struct acpi_cpufreq_data
*data
;
368 struct cpufreq_policy
*policy
;
370 unsigned int cached_freq
;
372 pr_debug("get_cur_freq_on_cpu (%d)\n", cpu
);
374 policy
= cpufreq_cpu_get(cpu
);
375 if (unlikely(!policy
))
378 data
= policy
->driver_data
;
379 cpufreq_cpu_put(policy
);
380 if (unlikely(!data
|| !data
->acpi_data
|| !data
->freq_table
))
383 cached_freq
= data
->freq_table
[data
->acpi_data
->state
].frequency
;
384 freq
= extract_freq(get_cur_val(cpumask_of(cpu
), data
), data
);
385 if (freq
!= cached_freq
) {
387 * The dreaded BIOS frequency change behind our back.
388 * Force set the frequency on next target call.
393 pr_debug("cur freq = %u\n", freq
);
398 static unsigned int check_freqs(const struct cpumask
*mask
, unsigned int freq
,
399 struct acpi_cpufreq_data
*data
)
401 unsigned int cur_freq
;
404 for (i
= 0; i
< 100; i
++) {
405 cur_freq
= extract_freq(get_cur_val(mask
, data
), data
);
406 if (cur_freq
== freq
)
413 static int acpi_cpufreq_target(struct cpufreq_policy
*policy
,
416 struct acpi_cpufreq_data
*data
= policy
->driver_data
;
417 struct acpi_processor_performance
*perf
;
419 unsigned int next_perf_state
= 0; /* Index into perf table */
422 if (unlikely(data
== NULL
||
423 data
->acpi_data
== NULL
|| data
->freq_table
== NULL
)) {
427 perf
= data
->acpi_data
;
428 next_perf_state
= data
->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",
435 pr_debug("Already at target state (P%d)\n",
441 switch (data
->cpu_feature
) {
442 case SYSTEM_INTEL_MSR_CAPABLE
:
443 cmd
.type
= SYSTEM_INTEL_MSR_CAPABLE
;
444 cmd
.addr
.msr
.reg
= MSR_IA32_PERF_CTL
;
445 cmd
.val
= (u32
) perf
->states
[next_perf_state
].control
;
447 case SYSTEM_AMD_MSR_CAPABLE
:
448 cmd
.type
= SYSTEM_AMD_MSR_CAPABLE
;
449 cmd
.addr
.msr
.reg
= MSR_AMD_PERF_CTL
;
450 cmd
.val
= (u32
) perf
->states
[next_perf_state
].control
;
452 case SYSTEM_IO_CAPABLE
:
453 cmd
.type
= SYSTEM_IO_CAPABLE
;
454 cmd
.addr
.io
.port
= perf
->control_register
.address
;
455 cmd
.addr
.io
.bit_width
= perf
->control_register
.bit_width
;
456 cmd
.val
= (u32
) perf
->states
[next_perf_state
].control
;
463 /* cpufreq holds the hotplug lock, so we are safe from here on */
464 if (policy
->shared_type
!= CPUFREQ_SHARED_TYPE_ANY
)
465 cmd
.mask
= policy
->cpus
;
467 cmd
.mask
= cpumask_of(policy
->cpu
);
471 if (acpi_pstate_strict
) {
472 if (!check_freqs(cmd
.mask
, data
->freq_table
[index
].frequency
,
474 pr_debug("acpi_cpufreq_target failed (%d)\n",
481 perf
->state
= next_perf_state
;
488 acpi_cpufreq_guess_freq(struct acpi_cpufreq_data
*data
, unsigned int cpu
)
490 struct acpi_processor_performance
*perf
= data
->acpi_data
;
493 /* search the closest match to cpu_khz */
496 unsigned long freqn
= perf
->states
[0].core_frequency
* 1000;
498 for (i
= 0; i
< (perf
->state_count
-1); i
++) {
500 freqn
= perf
->states
[i
+1].core_frequency
* 1000;
501 if ((2 * cpu_khz
) > (freqn
+ freq
)) {
506 perf
->state
= perf
->state_count
-1;
509 /* assume CPU is at P0... */
511 return perf
->states
[0].core_frequency
* 1000;
515 static void free_acpi_perf_data(void)
519 /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
520 for_each_possible_cpu(i
)
521 free_cpumask_var(per_cpu_ptr(acpi_perf_data
, i
)
523 free_percpu(acpi_perf_data
);
526 static int boost_notify(struct notifier_block
*nb
, unsigned long action
,
529 unsigned cpu
= (long)hcpu
;
530 const struct cpumask
*cpumask
;
532 cpumask
= get_cpu_mask(cpu
);
535 * Clear the boost-disable bit on the CPU_DOWN path so that
536 * this cpu cannot block the remaining ones from boosting. On
537 * the CPU_UP path we simply keep the boost-disable flag in
538 * sync with the current global state.
543 case CPU_UP_PREPARE_FROZEN
:
544 boost_set_msrs(acpi_cpufreq_driver
.boost_enabled
, cpumask
);
547 case CPU_DOWN_PREPARE
:
548 case CPU_DOWN_PREPARE_FROZEN
:
549 boost_set_msrs(1, cpumask
);
560 static struct notifier_block boost_nb
= {
561 .notifier_call
= boost_notify
,
565 * acpi_cpufreq_early_init - initialize ACPI P-States library
567 * Initialize the ACPI P-States library (drivers/acpi/processor_perflib.c)
568 * in order to determine correct frequency and voltage pairings. We can
569 * do _PDC and _PSD and find out the processor dependency for the
570 * actual init that will happen later...
572 static int __init
acpi_cpufreq_early_init(void)
575 pr_debug("acpi_cpufreq_early_init\n");
577 acpi_perf_data
= alloc_percpu(struct acpi_processor_performance
);
578 if (!acpi_perf_data
) {
579 pr_debug("Memory allocation error for acpi_perf_data.\n");
582 for_each_possible_cpu(i
) {
583 if (!zalloc_cpumask_var_node(
584 &per_cpu_ptr(acpi_perf_data
, i
)->shared_cpu_map
,
585 GFP_KERNEL
, cpu_to_node(i
))) {
587 /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
588 free_acpi_perf_data();
593 /* Do initialization in ACPI core */
594 acpi_processor_preregister_performance(acpi_perf_data
);
600 * Some BIOSes do SW_ANY coordination internally, either set it up in hw
601 * or do it in BIOS firmware and won't inform about it to OS. If not
602 * detected, this has a side effect of making CPU run at a different speed
603 * than OS intended it to run at. Detect it and handle it cleanly.
605 static int bios_with_sw_any_bug
;
607 static int sw_any_bug_found(const struct dmi_system_id
*d
)
609 bios_with_sw_any_bug
= 1;
613 static const struct dmi_system_id sw_any_bug_dmi_table
[] = {
615 .callback
= sw_any_bug_found
,
616 .ident
= "Supermicro Server X6DLP",
618 DMI_MATCH(DMI_SYS_VENDOR
, "Supermicro"),
619 DMI_MATCH(DMI_BIOS_VERSION
, "080010"),
620 DMI_MATCH(DMI_PRODUCT_NAME
, "X6DLP"),
626 static int acpi_cpufreq_blacklist(struct cpuinfo_x86
*c
)
628 /* Intel Xeon Processor 7100 Series Specification Update
629 * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
630 * AL30: A Machine Check Exception (MCE) Occurring during an
631 * Enhanced Intel SpeedStep Technology Ratio Change May Cause
632 * Both Processor Cores to Lock Up. */
633 if (c
->x86_vendor
== X86_VENDOR_INTEL
) {
634 if ((c
->x86
== 15) &&
635 (c
->x86_model
== 6) &&
636 (c
->x86_mask
== 8)) {
637 printk(KERN_INFO
"acpi-cpufreq: Intel(R) "
638 "Xeon(R) 7100 Errata AL30, processors may "
639 "lock up on frequency changes: disabling "
648 static int acpi_cpufreq_cpu_init(struct cpufreq_policy
*policy
)
651 unsigned int valid_states
= 0;
652 unsigned int cpu
= policy
->cpu
;
653 struct acpi_cpufreq_data
*data
;
654 unsigned int result
= 0;
655 struct cpuinfo_x86
*c
= &cpu_data(policy
->cpu
);
656 struct acpi_processor_performance
*perf
;
658 static int blacklisted
;
661 pr_debug("acpi_cpufreq_cpu_init\n");
666 blacklisted
= acpi_cpufreq_blacklist(c
);
671 data
= kzalloc(sizeof(*data
), GFP_KERNEL
);
675 if (!zalloc_cpumask_var(&data
->freqdomain_cpus
, GFP_KERNEL
)) {
680 data
->acpi_data
= per_cpu_ptr(acpi_perf_data
, cpu
);
681 data
->acpi_perf_cpu
= cpu
;
682 policy
->driver_data
= data
;
684 if (cpu_has(c
, X86_FEATURE_CONSTANT_TSC
))
685 acpi_cpufreq_driver
.flags
|= CPUFREQ_CONST_LOOPS
;
687 result
= acpi_processor_register_performance(data
->acpi_data
, cpu
);
691 perf
= data
->acpi_data
;
692 policy
->shared_type
= perf
->shared_type
;
695 * Will let policy->cpus know about dependency only when software
696 * coordination is required.
698 if (policy
->shared_type
== CPUFREQ_SHARED_TYPE_ALL
||
699 policy
->shared_type
== CPUFREQ_SHARED_TYPE_ANY
) {
700 cpumask_copy(policy
->cpus
, perf
->shared_cpu_map
);
702 cpumask_copy(data
->freqdomain_cpus
, perf
->shared_cpu_map
);
705 dmi_check_system(sw_any_bug_dmi_table
);
706 if (bios_with_sw_any_bug
&& !policy_is_shared(policy
)) {
707 policy
->shared_type
= CPUFREQ_SHARED_TYPE_ALL
;
708 cpumask_copy(policy
->cpus
, topology_core_cpumask(cpu
));
711 if (check_amd_hwpstate_cpu(cpu
) && !acpi_pstate_strict
) {
712 cpumask_clear(policy
->cpus
);
713 cpumask_set_cpu(cpu
, policy
->cpus
);
714 cpumask_copy(data
->freqdomain_cpus
,
715 topology_sibling_cpumask(cpu
));
716 policy
->shared_type
= CPUFREQ_SHARED_TYPE_HW
;
717 pr_info_once(PFX
"overriding BIOS provided _PSD data\n");
721 /* capability check */
722 if (perf
->state_count
<= 1) {
723 pr_debug("No P-States\n");
728 if (perf
->control_register
.space_id
!= perf
->status_register
.space_id
) {
733 switch (perf
->control_register
.space_id
) {
734 case ACPI_ADR_SPACE_SYSTEM_IO
:
735 if (boot_cpu_data
.x86_vendor
== X86_VENDOR_AMD
&&
736 boot_cpu_data
.x86
== 0xf) {
737 pr_debug("AMD K8 systems must use native drivers.\n");
741 pr_debug("SYSTEM IO addr space\n");
742 data
->cpu_feature
= SYSTEM_IO_CAPABLE
;
744 case ACPI_ADR_SPACE_FIXED_HARDWARE
:
745 pr_debug("HARDWARE addr space\n");
746 if (check_est_cpu(cpu
)) {
747 data
->cpu_feature
= SYSTEM_INTEL_MSR_CAPABLE
;
750 if (check_amd_hwpstate_cpu(cpu
)) {
751 data
->cpu_feature
= SYSTEM_AMD_MSR_CAPABLE
;
757 pr_debug("Unknown addr space %d\n",
758 (u32
) (perf
->control_register
.space_id
));
763 data
->freq_table
= kzalloc(sizeof(*data
->freq_table
) *
764 (perf
->state_count
+1), GFP_KERNEL
);
765 if (!data
->freq_table
) {
770 /* detect transition latency */
771 policy
->cpuinfo
.transition_latency
= 0;
772 for (i
= 0; i
< perf
->state_count
; i
++) {
773 if ((perf
->states
[i
].transition_latency
* 1000) >
774 policy
->cpuinfo
.transition_latency
)
775 policy
->cpuinfo
.transition_latency
=
776 perf
->states
[i
].transition_latency
* 1000;
779 /* Check for high latency (>20uS) from buggy BIOSes, like on T42 */
780 if (perf
->control_register
.space_id
== ACPI_ADR_SPACE_FIXED_HARDWARE
&&
781 policy
->cpuinfo
.transition_latency
> 20 * 1000) {
782 policy
->cpuinfo
.transition_latency
= 20 * 1000;
783 printk_once(KERN_INFO
784 "P-state transition latency capped at 20 uS\n");
788 for (i
= 0; i
< perf
->state_count
; i
++) {
789 if (i
> 0 && perf
->states
[i
].core_frequency
>=
790 data
->freq_table
[valid_states
-1].frequency
/ 1000)
793 data
->freq_table
[valid_states
].driver_data
= i
;
794 data
->freq_table
[valid_states
].frequency
=
795 perf
->states
[i
].core_frequency
* 1000;
798 data
->freq_table
[valid_states
].frequency
= CPUFREQ_TABLE_END
;
801 result
= cpufreq_table_validate_and_show(policy
, data
->freq_table
);
805 if (perf
->states
[0].core_frequency
* 1000 != policy
->cpuinfo
.max_freq
)
806 printk(KERN_WARNING FW_WARN
"P-state 0 is not max freq\n");
808 switch (perf
->control_register
.space_id
) {
809 case ACPI_ADR_SPACE_SYSTEM_IO
:
811 * The core will not set policy->cur, because
812 * cpufreq_driver->get is NULL, so we need to set it here.
813 * However, we have to guess it, because the current speed is
814 * unknown and not detectable via IO ports.
816 policy
->cur
= acpi_cpufreq_guess_freq(data
, policy
->cpu
);
818 case ACPI_ADR_SPACE_FIXED_HARDWARE
:
819 acpi_cpufreq_driver
.get
= get_cur_freq_on_cpu
;
825 /* notify BIOS that we exist */
826 acpi_processor_notify_smm(THIS_MODULE
);
828 pr_debug("CPU%u - ACPI performance management activated.\n", cpu
);
829 for (i
= 0; i
< perf
->state_count
; i
++)
830 pr_debug(" %cP%d: %d MHz, %d mW, %d uS\n",
831 (i
== perf
->state
? '*' : ' '), i
,
832 (u32
) perf
->states
[i
].core_frequency
,
833 (u32
) perf
->states
[i
].power
,
834 (u32
) perf
->states
[i
].transition_latency
);
837 * the first call to ->target() should result in us actually
838 * writing something to the appropriate registers.
845 kfree(data
->freq_table
);
847 acpi_processor_unregister_performance(cpu
);
849 free_cpumask_var(data
->freqdomain_cpus
);
852 policy
->driver_data
= NULL
;
857 static int acpi_cpufreq_cpu_exit(struct cpufreq_policy
*policy
)
859 struct acpi_cpufreq_data
*data
= policy
->driver_data
;
861 pr_debug("acpi_cpufreq_cpu_exit\n");
864 policy
->driver_data
= NULL
;
865 acpi_processor_unregister_performance(data
->acpi_perf_cpu
);
866 free_cpumask_var(data
->freqdomain_cpus
);
867 kfree(data
->freq_table
);
874 static int acpi_cpufreq_resume(struct cpufreq_policy
*policy
)
876 struct acpi_cpufreq_data
*data
= policy
->driver_data
;
878 pr_debug("acpi_cpufreq_resume\n");
885 static struct freq_attr
*acpi_cpufreq_attr
[] = {
886 &cpufreq_freq_attr_scaling_available_freqs
,
888 NULL
, /* this is a placeholder for cpb, do not remove */
892 static struct cpufreq_driver acpi_cpufreq_driver
= {
893 .verify
= cpufreq_generic_frequency_table_verify
,
894 .target_index
= acpi_cpufreq_target
,
895 .bios_limit
= acpi_processor_get_bios_limit
,
896 .init
= acpi_cpufreq_cpu_init
,
897 .exit
= acpi_cpufreq_cpu_exit
,
898 .resume
= acpi_cpufreq_resume
,
899 .name
= "acpi-cpufreq",
900 .attr
= acpi_cpufreq_attr
,
901 .set_boost
= _store_boost
,
904 static void __init
acpi_cpufreq_boost_init(void)
906 if (boot_cpu_has(X86_FEATURE_CPB
) || boot_cpu_has(X86_FEATURE_IDA
)) {
912 acpi_cpufreq_driver
.boost_supported
= true;
913 acpi_cpufreq_driver
.boost_enabled
= boost_state(0);
915 cpu_notifier_register_begin();
917 /* Force all MSRs to the same value */
918 boost_set_msrs(acpi_cpufreq_driver
.boost_enabled
,
921 __register_cpu_notifier(&boost_nb
);
923 cpu_notifier_register_done();
927 static void acpi_cpufreq_boost_exit(void)
930 unregister_cpu_notifier(&boost_nb
);
937 static int __init
acpi_cpufreq_init(void)
944 /* don't keep reloading if cpufreq_driver exists */
945 if (cpufreq_get_current_driver())
948 pr_debug("acpi_cpufreq_init\n");
950 ret
= acpi_cpufreq_early_init();
954 #ifdef CONFIG_X86_ACPI_CPUFREQ_CPB
955 /* this is a sysfs file with a strange name and an even stranger
956 * semantic - per CPU instantiation, but system global effect.
957 * Lets enable it only on AMD CPUs for compatibility reasons and
958 * only if configured. This is considered legacy code, which
959 * will probably be removed at some point in the future.
961 if (check_amd_hwpstate_cpu(0)) {
962 struct freq_attr
**iter
;
964 pr_debug("adding sysfs entry for cpb\n");
966 for (iter
= acpi_cpufreq_attr
; *iter
!= NULL
; iter
++)
969 /* make sure there is a terminator behind it */
974 acpi_cpufreq_boost_init();
976 ret
= cpufreq_register_driver(&acpi_cpufreq_driver
);
978 free_acpi_perf_data();
979 acpi_cpufreq_boost_exit();
984 static void __exit
acpi_cpufreq_exit(void)
986 pr_debug("acpi_cpufreq_exit\n");
988 acpi_cpufreq_boost_exit();
990 cpufreq_unregister_driver(&acpi_cpufreq_driver
);
992 free_acpi_perf_data();
995 module_param(acpi_pstate_strict
, uint
, 0644);
996 MODULE_PARM_DESC(acpi_pstate_strict
,
997 "value 0 or non-zero. non-zero -> strict ACPI checks are "
998 "performed during frequency changes.");
1000 late_initcall(acpi_cpufreq_init
);
1001 module_exit(acpi_cpufreq_exit
);
1003 static const struct x86_cpu_id acpi_cpufreq_ids
[] = {
1004 X86_FEATURE_MATCH(X86_FEATURE_ACPI
),
1005 X86_FEATURE_MATCH(X86_FEATURE_HW_PSTATE
),
1008 MODULE_DEVICE_TABLE(x86cpu
, acpi_cpufreq_ids
);
1010 static const struct acpi_device_id processor_device_ids
[] = {
1011 {ACPI_PROCESSOR_OBJECT_HID
, },
1012 {ACPI_PROCESSOR_DEVICE_HID
, },
1015 MODULE_DEVICE_TABLE(acpi
, processor_device_ids
);
1017 MODULE_ALIAS("acpi");