2 * processor_throttling.c - Throttling submodule of the ACPI processor 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) 2004 Dominik Brodowski <linux@brodo.de>
7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
8 * - Added processor hotplug support
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or (at
15 * your option) any later version.
17 * This program is distributed in the hope that it will be useful, but
18 * WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 * General Public License for more details.
22 * You should have received a copy of the GNU General Public License along
23 * with this program; if not, write to the Free Software Foundation, Inc.,
24 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
26 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/sched.h>
33 #include <linux/cpufreq.h>
34 #include <linux/proc_fs.h>
35 #include <linux/seq_file.h>
38 #include <asm/uaccess.h>
40 #include <acpi/acpi_bus.h>
41 #include <acpi/processor.h>
43 #define ACPI_PROCESSOR_COMPONENT 0x01000000
44 #define ACPI_PROCESSOR_CLASS "processor"
45 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
46 ACPI_MODULE_NAME("processor_throttling");
48 struct throttling_tstate
{
49 unsigned int cpu
; /* cpu nr */
50 int target_state
; /* target T-state */
53 #define THROTTLING_PRECHANGE (1)
54 #define THROTTLING_POSTCHANGE (2)
56 static int acpi_processor_get_throttling(struct acpi_processor
*pr
);
57 int acpi_processor_set_throttling(struct acpi_processor
*pr
, int state
);
59 static int acpi_processor_update_tsd_coord(void)
61 int count
, count_target
;
64 cpumask_t covered_cpus
;
65 struct acpi_processor
*pr
, *match_pr
;
66 struct acpi_tsd_package
*pdomain
, *match_pdomain
;
67 struct acpi_processor_throttling
*pthrottling
, *match_pthrottling
;
70 * Now that we have _TSD data from all CPUs, lets setup T-state
71 * coordination between all CPUs.
73 for_each_possible_cpu(i
) {
74 pr
= per_cpu(processors
, i
);
78 /* Basic validity check for domain info */
79 pthrottling
= &(pr
->throttling
);
82 * If tsd package for one cpu is invalid, the coordination
83 * among all CPUs is thought as invalid.
86 if (!pthrottling
->tsd_valid_flag
) {
94 cpus_clear(covered_cpus
);
95 for_each_possible_cpu(i
) {
96 pr
= per_cpu(processors
, i
);
100 if (cpu_isset(i
, covered_cpus
))
102 pthrottling
= &pr
->throttling
;
104 pdomain
= &(pthrottling
->domain_info
);
105 cpu_set(i
, pthrottling
->shared_cpu_map
);
106 cpu_set(i
, covered_cpus
);
108 * If the number of processor in the TSD domain is 1, it is
109 * unnecessary to parse the coordination for this CPU.
111 if (pdomain
->num_processors
<= 1)
114 /* Validate the Domain info */
115 count_target
= pdomain
->num_processors
;
118 for_each_possible_cpu(j
) {
122 match_pr
= per_cpu(processors
, j
);
126 match_pthrottling
= &(match_pr
->throttling
);
127 match_pdomain
= &(match_pthrottling
->domain_info
);
128 if (match_pdomain
->domain
!= pdomain
->domain
)
131 /* Here i and j are in the same domain.
132 * If two TSD packages have the same domain, they
133 * should have the same num_porcessors and
134 * coordination type. Otherwise it will be regarded
137 if (match_pdomain
->num_processors
!= count_target
) {
142 if (pdomain
->coord_type
!= match_pdomain
->coord_type
) {
147 cpu_set(j
, covered_cpus
);
148 cpu_set(j
, pthrottling
->shared_cpu_map
);
151 for_each_possible_cpu(j
) {
155 match_pr
= per_cpu(processors
, j
);
159 match_pthrottling
= &(match_pr
->throttling
);
160 match_pdomain
= &(match_pthrottling
->domain_info
);
161 if (match_pdomain
->domain
!= pdomain
->domain
)
165 * If some CPUS have the same domain, they
166 * will have the same shared_cpu_map.
168 match_pthrottling
->shared_cpu_map
=
169 pthrottling
->shared_cpu_map
;
174 for_each_possible_cpu(i
) {
175 pr
= per_cpu(processors
, i
);
180 * Assume no coordination on any error parsing domain info.
181 * The coordination type will be forced as SW_ALL.
184 pthrottling
= &(pr
->throttling
);
185 cpus_clear(pthrottling
->shared_cpu_map
);
186 cpu_set(i
, pthrottling
->shared_cpu_map
);
187 pthrottling
->shared_type
= DOMAIN_COORD_TYPE_SW_ALL
;
195 * Update the T-state coordination after the _TSD
196 * data for all cpus is obtained.
198 void acpi_processor_throttling_init(void)
200 if (acpi_processor_update_tsd_coord())
201 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
202 "Assume no T-state coordination\n"));
207 static int acpi_processor_throttling_notifier(unsigned long event
, void *data
)
209 struct throttling_tstate
*p_tstate
= data
;
210 struct acpi_processor
*pr
;
213 struct acpi_processor_limit
*p_limit
;
214 struct acpi_processor_throttling
*p_throttling
;
217 pr
= per_cpu(processors
, cpu
);
219 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Invalid pr pointer\n"));
222 if (!pr
->flags
.throttling
) {
223 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Throttling control is "
224 "unsupported on CPU %d\n", cpu
));
227 target_state
= p_tstate
->target_state
;
228 p_throttling
= &(pr
->throttling
);
230 case THROTTLING_PRECHANGE
:
232 * Prechange event is used to choose one proper t-state,
233 * which meets the limits of thermal, user and _TPC.
235 p_limit
= &pr
->limit
;
236 if (p_limit
->thermal
.tx
> target_state
)
237 target_state
= p_limit
->thermal
.tx
;
238 if (p_limit
->user
.tx
> target_state
)
239 target_state
= p_limit
->user
.tx
;
240 if (pr
->throttling_platform_limit
> target_state
)
241 target_state
= pr
->throttling_platform_limit
;
242 if (target_state
>= p_throttling
->state_count
) {
244 "Exceed the limit of T-state \n");
245 target_state
= p_throttling
->state_count
- 1;
247 p_tstate
->target_state
= target_state
;
248 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "PreChange Event:"
249 "target T-state of CPU %d is T%d\n",
252 case THROTTLING_POSTCHANGE
:
254 * Postchange event is only used to update the
255 * T-state flag of acpi_processor_throttling.
257 p_throttling
->state
= target_state
;
258 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "PostChange Event:"
259 "CPU %d is switched to T%d\n",
264 "Unsupported Throttling notifier event\n");
272 * _TPC - Throttling Present Capabilities
274 static int acpi_processor_get_platform_limit(struct acpi_processor
*pr
)
276 acpi_status status
= 0;
277 unsigned long tpc
= 0;
281 status
= acpi_evaluate_integer(pr
->handle
, "_TPC", NULL
, &tpc
);
282 if (ACPI_FAILURE(status
)) {
283 if (status
!= AE_NOT_FOUND
) {
284 ACPI_EXCEPTION((AE_INFO
, status
, "Evaluating _TPC"));
288 pr
->throttling_platform_limit
= (int)tpc
;
292 int acpi_processor_tstate_has_changed(struct acpi_processor
*pr
)
295 int throttling_limit
;
297 struct acpi_processor_limit
*limit
;
300 result
= acpi_processor_get_platform_limit(pr
);
302 /* Throttling Limit is unsupported */
306 throttling_limit
= pr
->throttling_platform_limit
;
307 if (throttling_limit
>= pr
->throttling
.state_count
) {
308 /* Uncorrect Throttling Limit */
312 current_state
= pr
->throttling
.state
;
313 if (current_state
> throttling_limit
) {
315 * The current state can meet the requirement of
316 * _TPC limit. But it is reasonable that OSPM changes
317 * t-states from high to low for better performance.
318 * Of course the limit condition of thermal
319 * and user should be considered.
322 target_state
= throttling_limit
;
323 if (limit
->thermal
.tx
> target_state
)
324 target_state
= limit
->thermal
.tx
;
325 if (limit
->user
.tx
> target_state
)
326 target_state
= limit
->user
.tx
;
327 } else if (current_state
== throttling_limit
) {
329 * Unnecessary to change the throttling state
334 * If the current state is lower than the limit of _TPC, it
335 * will be forced to switch to the throttling state defined
336 * by throttling_platfor_limit.
337 * Because the previous state meets with the limit condition
338 * of thermal and user, it is unnecessary to check it again.
340 target_state
= throttling_limit
;
342 return acpi_processor_set_throttling(pr
, target_state
);
346 * _PTC - Processor Throttling Control (and status) register location
348 static int acpi_processor_get_throttling_control(struct acpi_processor
*pr
)
351 acpi_status status
= 0;
352 struct acpi_buffer buffer
= { ACPI_ALLOCATE_BUFFER
, NULL
};
353 union acpi_object
*ptc
= NULL
;
354 union acpi_object obj
= { 0 };
355 struct acpi_processor_throttling
*throttling
;
357 status
= acpi_evaluate_object(pr
->handle
, "_PTC", NULL
, &buffer
);
358 if (ACPI_FAILURE(status
)) {
359 if (status
!= AE_NOT_FOUND
) {
360 ACPI_EXCEPTION((AE_INFO
, status
, "Evaluating _PTC"));
365 ptc
= (union acpi_object
*)buffer
.pointer
;
366 if (!ptc
|| (ptc
->type
!= ACPI_TYPE_PACKAGE
)
367 || (ptc
->package
.count
!= 2)) {
368 printk(KERN_ERR PREFIX
"Invalid _PTC data\n");
377 obj
= ptc
->package
.elements
[0];
379 if ((obj
.type
!= ACPI_TYPE_BUFFER
)
380 || (obj
.buffer
.length
< sizeof(struct acpi_ptc_register
))
381 || (obj
.buffer
.pointer
== NULL
)) {
382 printk(KERN_ERR PREFIX
383 "Invalid _PTC data (control_register)\n");
387 memcpy(&pr
->throttling
.control_register
, obj
.buffer
.pointer
,
388 sizeof(struct acpi_ptc_register
));
394 obj
= ptc
->package
.elements
[1];
396 if ((obj
.type
!= ACPI_TYPE_BUFFER
)
397 || (obj
.buffer
.length
< sizeof(struct acpi_ptc_register
))
398 || (obj
.buffer
.pointer
== NULL
)) {
399 printk(KERN_ERR PREFIX
"Invalid _PTC data (status_register)\n");
404 memcpy(&pr
->throttling
.status_register
, obj
.buffer
.pointer
,
405 sizeof(struct acpi_ptc_register
));
407 throttling
= &pr
->throttling
;
409 if ((throttling
->control_register
.bit_width
+
410 throttling
->control_register
.bit_offset
) > 32) {
411 printk(KERN_ERR PREFIX
"Invalid _PTC control register\n");
416 if ((throttling
->status_register
.bit_width
+
417 throttling
->status_register
.bit_offset
) > 32) {
418 printk(KERN_ERR PREFIX
"Invalid _PTC status register\n");
424 kfree(buffer
.pointer
);
430 * _TSS - Throttling Supported States
432 static int acpi_processor_get_throttling_states(struct acpi_processor
*pr
)
435 acpi_status status
= AE_OK
;
436 struct acpi_buffer buffer
= { ACPI_ALLOCATE_BUFFER
, NULL
};
437 struct acpi_buffer format
= { sizeof("NNNNN"), "NNNNN" };
438 struct acpi_buffer state
= { 0, NULL
};
439 union acpi_object
*tss
= NULL
;
442 status
= acpi_evaluate_object(pr
->handle
, "_TSS", NULL
, &buffer
);
443 if (ACPI_FAILURE(status
)) {
444 if (status
!= AE_NOT_FOUND
) {
445 ACPI_EXCEPTION((AE_INFO
, status
, "Evaluating _TSS"));
450 tss
= buffer
.pointer
;
451 if (!tss
|| (tss
->type
!= ACPI_TYPE_PACKAGE
)) {
452 printk(KERN_ERR PREFIX
"Invalid _TSS data\n");
457 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Found %d throttling states\n",
458 tss
->package
.count
));
460 pr
->throttling
.state_count
= tss
->package
.count
;
461 pr
->throttling
.states_tss
=
462 kmalloc(sizeof(struct acpi_processor_tx_tss
) * tss
->package
.count
,
464 if (!pr
->throttling
.states_tss
) {
469 for (i
= 0; i
< pr
->throttling
.state_count
; i
++) {
471 struct acpi_processor_tx_tss
*tx
=
472 (struct acpi_processor_tx_tss
*)&(pr
->throttling
.
475 state
.length
= sizeof(struct acpi_processor_tx_tss
);
478 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Extracting state %d\n", i
));
480 status
= acpi_extract_package(&(tss
->package
.elements
[i
]),
482 if (ACPI_FAILURE(status
)) {
483 ACPI_EXCEPTION((AE_INFO
, status
, "Invalid _TSS data"));
485 kfree(pr
->throttling
.states_tss
);
489 if (!tx
->freqpercentage
) {
490 printk(KERN_ERR PREFIX
491 "Invalid _TSS data: freq is zero\n");
493 kfree(pr
->throttling
.states_tss
);
499 kfree(buffer
.pointer
);
505 * _TSD - T-State Dependencies
507 static int acpi_processor_get_tsd(struct acpi_processor
*pr
)
510 acpi_status status
= AE_OK
;
511 struct acpi_buffer buffer
= { ACPI_ALLOCATE_BUFFER
, NULL
};
512 struct acpi_buffer format
= { sizeof("NNNNN"), "NNNNN" };
513 struct acpi_buffer state
= { 0, NULL
};
514 union acpi_object
*tsd
= NULL
;
515 struct acpi_tsd_package
*pdomain
;
516 struct acpi_processor_throttling
*pthrottling
;
518 pthrottling
= &pr
->throttling
;
519 pthrottling
->tsd_valid_flag
= 0;
521 status
= acpi_evaluate_object(pr
->handle
, "_TSD", NULL
, &buffer
);
522 if (ACPI_FAILURE(status
)) {
523 if (status
!= AE_NOT_FOUND
) {
524 ACPI_EXCEPTION((AE_INFO
, status
, "Evaluating _TSD"));
529 tsd
= buffer
.pointer
;
530 if (!tsd
|| (tsd
->type
!= ACPI_TYPE_PACKAGE
)) {
531 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
, "Invalid _TSD data\n"));
536 if (tsd
->package
.count
!= 1) {
537 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
, "Invalid _TSD data\n"));
542 pdomain
= &(pr
->throttling
.domain_info
);
544 state
.length
= sizeof(struct acpi_tsd_package
);
545 state
.pointer
= pdomain
;
547 status
= acpi_extract_package(&(tsd
->package
.elements
[0]),
549 if (ACPI_FAILURE(status
)) {
550 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
, "Invalid _TSD data\n"));
555 if (pdomain
->num_entries
!= ACPI_TSD_REV0_ENTRIES
) {
556 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
, "Unknown _TSD:num_entries\n"));
561 if (pdomain
->revision
!= ACPI_TSD_REV0_REVISION
) {
562 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
, "Unknown _TSD:revision\n"));
567 pthrottling
= &pr
->throttling
;
568 pthrottling
->tsd_valid_flag
= 1;
569 pthrottling
->shared_type
= pdomain
->coord_type
;
570 cpu_set(pr
->id
, pthrottling
->shared_cpu_map
);
572 * If the coordination type is not defined in ACPI spec,
573 * the tsd_valid_flag will be clear and coordination type
574 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
576 if (pdomain
->coord_type
!= DOMAIN_COORD_TYPE_SW_ALL
&&
577 pdomain
->coord_type
!= DOMAIN_COORD_TYPE_SW_ANY
&&
578 pdomain
->coord_type
!= DOMAIN_COORD_TYPE_HW_ALL
) {
579 pthrottling
->tsd_valid_flag
= 0;
580 pthrottling
->shared_type
= DOMAIN_COORD_TYPE_SW_ALL
;
584 kfree(buffer
.pointer
);
588 /* --------------------------------------------------------------------------
590 -------------------------------------------------------------------------- */
591 static int acpi_processor_get_throttling_fadt(struct acpi_processor
*pr
)
601 if (!pr
->flags
.throttling
)
604 pr
->throttling
.state
= 0;
606 duty_mask
= pr
->throttling
.state_count
- 1;
608 duty_mask
<<= pr
->throttling
.duty_offset
;
612 value
= inl(pr
->throttling
.address
);
615 * Compute the current throttling state when throttling is enabled
619 duty_value
= value
& duty_mask
;
620 duty_value
>>= pr
->throttling
.duty_offset
;
623 state
= pr
->throttling
.state_count
- duty_value
;
626 pr
->throttling
.state
= state
;
630 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
631 "Throttling state is T%d (%d%% throttling applied)\n",
632 state
, pr
->throttling
.states
[state
].performance
));
638 static int acpi_throttling_rdmsr(struct acpi_processor
*pr
,
639 acpi_integer
* value
)
641 struct cpuinfo_x86
*c
;
642 u64 msr_high
, msr_low
;
650 if ((c
->x86_vendor
!= X86_VENDOR_INTEL
) ||
651 !cpu_has(c
, X86_FEATURE_ACPI
)) {
652 printk(KERN_ERR PREFIX
653 "HARDWARE addr space,NOT supported yet\n");
657 rdmsr_safe(MSR_IA32_THERM_CONTROL
,
658 (u32
*)&msr_low
, (u32
*) &msr_high
);
659 msr
= (msr_high
<< 32) | msr_low
;
660 *value
= (acpi_integer
) msr
;
666 static int acpi_throttling_wrmsr(struct acpi_processor
*pr
, acpi_integer value
)
668 struct cpuinfo_x86
*c
;
676 if ((c
->x86_vendor
!= X86_VENDOR_INTEL
) ||
677 !cpu_has(c
, X86_FEATURE_ACPI
)) {
678 printk(KERN_ERR PREFIX
679 "HARDWARE addr space,NOT supported yet\n");
682 wrmsr_safe(MSR_IA32_THERM_CONTROL
,
683 msr
& 0xffffffff, msr
>> 32);
689 static int acpi_throttling_rdmsr(struct acpi_processor
*pr
,
690 acpi_integer
* value
)
692 printk(KERN_ERR PREFIX
693 "HARDWARE addr space,NOT supported yet\n");
697 static int acpi_throttling_wrmsr(struct acpi_processor
*pr
, acpi_integer value
)
699 printk(KERN_ERR PREFIX
700 "HARDWARE addr space,NOT supported yet\n");
705 static int acpi_read_throttling_status(struct acpi_processor
*pr
,
708 u32 bit_width
, bit_offset
;
711 struct acpi_processor_throttling
*throttling
;
714 throttling
= &pr
->throttling
;
715 switch (throttling
->status_register
.space_id
) {
716 case ACPI_ADR_SPACE_SYSTEM_IO
:
718 bit_width
= throttling
->status_register
.bit_width
;
719 bit_offset
= throttling
->status_register
.bit_offset
;
721 acpi_os_read_port((acpi_io_address
) throttling
->status_register
.
722 address
, (u32
*) &ptc_value
,
723 (u32
) (bit_width
+ bit_offset
));
724 ptc_mask
= (1 << bit_width
) - 1;
725 *value
= (acpi_integer
) ((ptc_value
>> bit_offset
) & ptc_mask
);
728 case ACPI_ADR_SPACE_FIXED_HARDWARE
:
729 ret
= acpi_throttling_rdmsr(pr
, value
);
732 printk(KERN_ERR PREFIX
"Unknown addr space %d\n",
733 (u32
) (throttling
->status_register
.space_id
));
738 static int acpi_write_throttling_state(struct acpi_processor
*pr
,
741 u32 bit_width
, bit_offset
;
744 struct acpi_processor_throttling
*throttling
;
747 throttling
= &pr
->throttling
;
748 switch (throttling
->control_register
.space_id
) {
749 case ACPI_ADR_SPACE_SYSTEM_IO
:
750 bit_width
= throttling
->control_register
.bit_width
;
751 bit_offset
= throttling
->control_register
.bit_offset
;
752 ptc_mask
= (1 << bit_width
) - 1;
753 ptc_value
= value
& ptc_mask
;
755 acpi_os_write_port((acpi_io_address
) throttling
->
756 control_register
.address
,
757 (u32
) (ptc_value
<< bit_offset
),
758 (u32
) (bit_width
+ bit_offset
));
761 case ACPI_ADR_SPACE_FIXED_HARDWARE
:
762 ret
= acpi_throttling_wrmsr(pr
, value
);
765 printk(KERN_ERR PREFIX
"Unknown addr space %d\n",
766 (u32
) (throttling
->control_register
.space_id
));
771 static int acpi_get_throttling_state(struct acpi_processor
*pr
,
776 for (i
= 0; i
< pr
->throttling
.state_count
; i
++) {
777 struct acpi_processor_tx_tss
*tx
=
778 (struct acpi_processor_tx_tss
*)&(pr
->throttling
.
780 if (tx
->control
== value
)
783 if (i
> pr
->throttling
.state_count
)
788 static int acpi_get_throttling_value(struct acpi_processor
*pr
,
789 int state
, acpi_integer
*value
)
793 if (state
>= 0 && state
<= pr
->throttling
.state_count
) {
794 struct acpi_processor_tx_tss
*tx
=
795 (struct acpi_processor_tx_tss
*)&(pr
->throttling
.
797 *value
= tx
->control
;
803 static int acpi_processor_get_throttling_ptc(struct acpi_processor
*pr
)
812 if (!pr
->flags
.throttling
)
815 pr
->throttling
.state
= 0;
818 ret
= acpi_read_throttling_status(pr
, &value
);
820 state
= acpi_get_throttling_state(pr
, value
);
821 pr
->throttling
.state
= state
;
827 static int acpi_processor_get_throttling(struct acpi_processor
*pr
)
829 cpumask_t saved_mask
;
835 if (!pr
->flags
.throttling
)
838 * Migrate task to the cpu pointed by pr.
840 saved_mask
= current
->cpus_allowed
;
841 set_cpus_allowed_ptr(current
, &cpumask_of_cpu(pr
->id
));
842 ret
= pr
->throttling
.acpi_processor_get_throttling(pr
);
843 /* restore the previous state */
844 set_cpus_allowed_ptr(current
, &saved_mask
);
849 static int acpi_processor_get_fadt_info(struct acpi_processor
*pr
)
853 if (!pr
->throttling
.address
) {
854 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "No throttling register\n"));
856 } else if (!pr
->throttling
.duty_width
) {
857 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "No throttling states\n"));
860 /* TBD: Support duty_cycle values that span bit 4. */
861 else if ((pr
->throttling
.duty_offset
+ pr
->throttling
.duty_width
) > 4) {
862 printk(KERN_WARNING PREFIX
"duty_cycle spans bit 4\n");
866 pr
->throttling
.state_count
= 1 << acpi_gbl_FADT
.duty_width
;
869 * Compute state values. Note that throttling displays a linear power
870 * performance relationship (at 50% performance the CPU will consume
871 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
874 step
= (1000 / pr
->throttling
.state_count
);
876 for (i
= 0; i
< pr
->throttling
.state_count
; i
++) {
877 pr
->throttling
.states
[i
].performance
= 1000 - step
* i
;
878 pr
->throttling
.states
[i
].power
= 1000 - step
* i
;
883 static int acpi_processor_set_throttling_fadt(struct acpi_processor
*pr
,
893 if ((state
< 0) || (state
> (pr
->throttling
.state_count
- 1)))
896 if (!pr
->flags
.throttling
)
899 if (state
== pr
->throttling
.state
)
902 if (state
< pr
->throttling_platform_limit
)
905 * Calculate the duty_value and duty_mask.
908 duty_value
= pr
->throttling
.state_count
- state
;
910 duty_value
<<= pr
->throttling
.duty_offset
;
912 /* Used to clear all duty_value bits */
913 duty_mask
= pr
->throttling
.state_count
- 1;
915 duty_mask
<<= acpi_gbl_FADT
.duty_offset
;
916 duty_mask
= ~duty_mask
;
922 * Disable throttling by writing a 0 to bit 4. Note that we must
923 * turn it off before you can change the duty_value.
925 value
= inl(pr
->throttling
.address
);
928 outl(value
, pr
->throttling
.address
);
932 * Write the new duty_value and then enable throttling. Note
933 * that a state value of 0 leaves throttling disabled.
938 outl(value
, pr
->throttling
.address
);
941 outl(value
, pr
->throttling
.address
);
944 pr
->throttling
.state
= state
;
948 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
949 "Throttling state set to T%d (%d%%)\n", state
,
950 (pr
->throttling
.states
[state
].performance
? pr
->
951 throttling
.states
[state
].performance
/ 10 : 0)));
956 static int acpi_processor_set_throttling_ptc(struct acpi_processor
*pr
,
965 if ((state
< 0) || (state
> (pr
->throttling
.state_count
- 1)))
968 if (!pr
->flags
.throttling
)
971 if (state
== pr
->throttling
.state
)
974 if (state
< pr
->throttling_platform_limit
)
978 ret
= acpi_get_throttling_value(pr
, state
, &value
);
980 acpi_write_throttling_state(pr
, value
);
981 pr
->throttling
.state
= state
;
987 int acpi_processor_set_throttling(struct acpi_processor
*pr
, int state
)
989 cpumask_t saved_mask
;
992 struct acpi_processor
*match_pr
;
993 struct acpi_processor_throttling
*p_throttling
;
994 struct throttling_tstate t_state
;
995 cpumask_t online_throttling_cpus
;
1000 if (!pr
->flags
.throttling
)
1003 if ((state
< 0) || (state
> (pr
->throttling
.state_count
- 1)))
1006 saved_mask
= current
->cpus_allowed
;
1007 t_state
.target_state
= state
;
1008 p_throttling
= &(pr
->throttling
);
1009 cpus_and(online_throttling_cpus
, cpu_online_map
,
1010 p_throttling
->shared_cpu_map
);
1012 * The throttling notifier will be called for every
1013 * affected cpu in order to get one proper T-state.
1014 * The notifier event is THROTTLING_PRECHANGE.
1016 for_each_cpu_mask_nr(i
, online_throttling_cpus
) {
1018 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE
,
1022 * The function of acpi_processor_set_throttling will be called
1023 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1024 * it is necessary to call it for every affected cpu. Otherwise
1025 * it can be called only for the cpu pointed by pr.
1027 if (p_throttling
->shared_type
== DOMAIN_COORD_TYPE_SW_ANY
) {
1028 set_cpus_allowed_ptr(current
, &cpumask_of_cpu(pr
->id
));
1029 ret
= p_throttling
->acpi_processor_set_throttling(pr
,
1030 t_state
.target_state
);
1033 * When the T-state coordination is SW_ALL or HW_ALL,
1034 * it is necessary to set T-state for every affected
1037 for_each_cpu_mask_nr(i
, online_throttling_cpus
) {
1038 match_pr
= per_cpu(processors
, i
);
1040 * If the pointer is invalid, we will report the
1041 * error message and continue.
1044 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
1045 "Invalid Pointer for CPU %d\n", i
));
1049 * If the throttling control is unsupported on CPU i,
1050 * we will report the error message and continue.
1052 if (!match_pr
->flags
.throttling
) {
1053 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
1054 "Throttling Controll is unsupported "
1059 set_cpus_allowed_ptr(current
, &cpumask_of_cpu(i
));
1060 ret
= match_pr
->throttling
.
1061 acpi_processor_set_throttling(
1062 match_pr
, t_state
.target_state
);
1066 * After the set_throttling is called, the
1067 * throttling notifier is called for every
1068 * affected cpu to update the T-states.
1069 * The notifier event is THROTTLING_POSTCHANGE
1071 for_each_cpu_mask_nr(i
, online_throttling_cpus
) {
1073 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE
,
1076 /* restore the previous state */
1077 set_cpus_allowed_ptr(current
, &saved_mask
);
1081 int acpi_processor_get_throttling_info(struct acpi_processor
*pr
)
1084 struct acpi_processor_throttling
*pthrottling
;
1086 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
1087 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1088 pr
->throttling
.address
,
1089 pr
->throttling
.duty_offset
,
1090 pr
->throttling
.duty_width
));
1096 * Evaluate _PTC, _TSS and _TPC
1097 * They must all be present or none of them can be used.
1099 if (acpi_processor_get_throttling_control(pr
) ||
1100 acpi_processor_get_throttling_states(pr
) ||
1101 acpi_processor_get_platform_limit(pr
))
1103 pr
->throttling
.acpi_processor_get_throttling
=
1104 &acpi_processor_get_throttling_fadt
;
1105 pr
->throttling
.acpi_processor_set_throttling
=
1106 &acpi_processor_set_throttling_fadt
;
1107 if (acpi_processor_get_fadt_info(pr
))
1110 pr
->throttling
.acpi_processor_get_throttling
=
1111 &acpi_processor_get_throttling_ptc
;
1112 pr
->throttling
.acpi_processor_set_throttling
=
1113 &acpi_processor_set_throttling_ptc
;
1117 * If TSD package for one CPU can't be parsed successfully, it means
1118 * that this CPU will have no coordination with other CPUs.
1120 if (acpi_processor_get_tsd(pr
)) {
1121 pthrottling
= &pr
->throttling
;
1122 pthrottling
->tsd_valid_flag
= 0;
1123 cpu_set(pr
->id
, pthrottling
->shared_cpu_map
);
1124 pthrottling
->shared_type
= DOMAIN_COORD_TYPE_SW_ALL
;
1128 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1129 * This shouldn't be an issue as few (if any) mobile systems ever
1132 if (errata
.piix4
.throttle
) {
1133 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
1134 "Throttling not supported on PIIX4 A- or B-step\n"));
1138 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Found %d throttling states\n",
1139 pr
->throttling
.state_count
));
1141 pr
->flags
.throttling
= 1;
1144 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1145 * thermal) decide to lower performance if it so chooses, but for now
1146 * we'll crank up the speed.
1149 result
= acpi_processor_get_throttling(pr
);
1153 if (pr
->throttling
.state
) {
1154 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
1155 "Disabling throttling (was T%d)\n",
1156 pr
->throttling
.state
));
1157 result
= acpi_processor_set_throttling(pr
, 0);
1164 pr
->flags
.throttling
= 0;
1169 /* proc interface */
1171 static int acpi_processor_throttling_seq_show(struct seq_file
*seq
,
1174 struct acpi_processor
*pr
= seq
->private;
1181 if (!(pr
->throttling
.state_count
> 0)) {
1182 seq_puts(seq
, "<not supported>\n");
1186 result
= acpi_processor_get_throttling(pr
);
1190 "Could not determine current throttling state.\n");
1194 seq_printf(seq
, "state count: %d\n"
1195 "active state: T%d\n"
1196 "state available: T%d to T%d\n",
1197 pr
->throttling
.state_count
, pr
->throttling
.state
,
1198 pr
->throttling_platform_limit
,
1199 pr
->throttling
.state_count
- 1);
1201 seq_puts(seq
, "states:\n");
1202 if (pr
->throttling
.acpi_processor_get_throttling
==
1203 acpi_processor_get_throttling_fadt
) {
1204 for (i
= 0; i
< pr
->throttling
.state_count
; i
++)
1205 seq_printf(seq
, " %cT%d: %02d%%\n",
1206 (i
== pr
->throttling
.state
? '*' : ' '), i
,
1207 (pr
->throttling
.states
[i
].performance
? pr
->
1208 throttling
.states
[i
].performance
/ 10 : 0));
1210 for (i
= 0; i
< pr
->throttling
.state_count
; i
++)
1211 seq_printf(seq
, " %cT%d: %02d%%\n",
1212 (i
== pr
->throttling
.state
? '*' : ' '), i
,
1213 (int)pr
->throttling
.states_tss
[i
].
1221 static int acpi_processor_throttling_open_fs(struct inode
*inode
,
1224 return single_open(file
, acpi_processor_throttling_seq_show
,
1228 static ssize_t
acpi_processor_write_throttling(struct file
*file
,
1229 const char __user
* buffer
,
1230 size_t count
, loff_t
* data
)
1233 struct seq_file
*m
= file
->private_data
;
1234 struct acpi_processor
*pr
= m
->private;
1235 char state_string
[5] = "";
1237 size_t state_val
= 0;
1238 char tmpbuf
[5] = "";
1240 if (!pr
|| (count
> sizeof(state_string
) - 1))
1243 if (copy_from_user(state_string
, buffer
, count
))
1246 state_string
[count
] = '\0';
1247 if ((count
> 0) && (state_string
[count
-1] == '\n'))
1248 state_string
[count
-1] = '\0';
1250 charp
= state_string
;
1251 if ((state_string
[0] == 't') || (state_string
[0] == 'T'))
1254 state_val
= simple_strtoul(charp
, NULL
, 0);
1255 if (state_val
>= pr
->throttling
.state_count
)
1258 snprintf(tmpbuf
, 5, "%zu", state_val
);
1260 if (strcmp(tmpbuf
, charp
) != 0)
1263 result
= acpi_processor_set_throttling(pr
, state_val
);
1270 struct file_operations acpi_processor_throttling_fops
= {
1271 .owner
= THIS_MODULE
,
1272 .open
= acpi_processor_throttling_open_fs
,
1274 .write
= acpi_processor_write_throttling
,
1275 .llseek
= seq_lseek
,
1276 .release
= single_release
,