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/acpi_drivers.h>
42 #include <acpi/processor.h>
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_var_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;
69 if (!alloc_cpumask_var(&covered_cpus, GFP_KERNEL))
73 * Now that we have _TSD data from all CPUs, lets setup T-state
74 * coordination between all CPUs.
76 for_each_possible_cpu(i) {
77 pr = per_cpu(processors, i);
81 /* Basic validity check for domain info */
82 pthrottling = &(pr->throttling);
85 * If tsd package for one cpu is invalid, the coordination
86 * among all CPUs is thought as invalid.
89 if (!pthrottling->tsd_valid_flag) {
97 cpumask_clear(covered_cpus);
98 for_each_possible_cpu(i) {
99 pr = per_cpu(processors, i);
103 if (cpumask_test_cpu(i, covered_cpus))
105 pthrottling = &pr->throttling;
107 pdomain = &(pthrottling->domain_info);
108 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
109 cpumask_set_cpu(i, covered_cpus);
111 * If the number of processor in the TSD domain is 1, it is
112 * unnecessary to parse the coordination for this CPU.
114 if (pdomain->num_processors <= 1)
117 /* Validate the Domain info */
118 count_target = pdomain->num_processors;
121 for_each_possible_cpu(j) {
125 match_pr = per_cpu(processors, j);
129 match_pthrottling = &(match_pr->throttling);
130 match_pdomain = &(match_pthrottling->domain_info);
131 if (match_pdomain->domain != pdomain->domain)
134 /* Here i and j are in the same domain.
135 * If two TSD packages have the same domain, they
136 * should have the same num_porcessors and
137 * coordination type. Otherwise it will be regarded
140 if (match_pdomain->num_processors != count_target) {
145 if (pdomain->coord_type != match_pdomain->coord_type) {
150 cpumask_set_cpu(j, covered_cpus);
151 cpumask_set_cpu(j, pthrottling->shared_cpu_map);
154 for_each_possible_cpu(j) {
158 match_pr = per_cpu(processors, j);
162 match_pthrottling = &(match_pr->throttling);
163 match_pdomain = &(match_pthrottling->domain_info);
164 if (match_pdomain->domain != pdomain->domain)
168 * If some CPUS have the same domain, they
169 * will have the same shared_cpu_map.
171 cpumask_copy(match_pthrottling->shared_cpu_map,
172 pthrottling->shared_cpu_map);
177 free_cpumask_var(covered_cpus);
179 for_each_possible_cpu(i) {
180 pr = per_cpu(processors, i);
185 * Assume no coordination on any error parsing domain info.
186 * The coordination type will be forced as SW_ALL.
189 pthrottling = &(pr->throttling);
190 cpumask_clear(pthrottling->shared_cpu_map);
191 cpumask_set_cpu(i, pthrottling->shared_cpu_map);
192 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
200 * Update the T-state coordination after the _TSD
201 * data for all cpus is obtained.
203 void acpi_processor_throttling_init(void)
205 if (acpi_processor_update_tsd_coord())
206 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
207 "Assume no T-state coordination\n"));
212 static int acpi_processor_throttling_notifier(unsigned long event, void *data)
214 struct throttling_tstate *p_tstate = data;
215 struct acpi_processor *pr;
218 struct acpi_processor_limit *p_limit;
219 struct acpi_processor_throttling *p_throttling;
222 pr = per_cpu(processors, cpu);
224 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Invalid pr pointer\n"));
227 if (!pr->flags.throttling) {
228 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Throttling control is "
229 "unsupported on CPU %d\n", cpu));
232 target_state = p_tstate->target_state;
233 p_throttling = &(pr->throttling);
235 case THROTTLING_PRECHANGE:
237 * Prechange event is used to choose one proper t-state,
238 * which meets the limits of thermal, user and _TPC.
240 p_limit = &pr->limit;
241 if (p_limit->thermal.tx > target_state)
242 target_state = p_limit->thermal.tx;
243 if (p_limit->user.tx > target_state)
244 target_state = p_limit->user.tx;
245 if (pr->throttling_platform_limit > target_state)
246 target_state = pr->throttling_platform_limit;
247 if (target_state >= p_throttling->state_count) {
249 "Exceed the limit of T-state \n");
250 target_state = p_throttling->state_count - 1;
252 p_tstate->target_state = target_state;
253 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PreChange Event:"
254 "target T-state of CPU %d is T%d\n",
257 case THROTTLING_POSTCHANGE:
259 * Postchange event is only used to update the
260 * T-state flag of acpi_processor_throttling.
262 p_throttling->state = target_state;
263 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PostChange Event:"
264 "CPU %d is switched to T%d\n",
269 "Unsupported Throttling notifier event\n");
277 * _TPC - Throttling Present Capabilities
279 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
281 acpi_status status = 0;
282 unsigned long long tpc = 0;
286 status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
287 if (ACPI_FAILURE(status)) {
288 if (status != AE_NOT_FOUND) {
289 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
293 pr->throttling_platform_limit = (int)tpc;
297 int acpi_processor_tstate_has_changed(struct acpi_processor *pr)
300 int throttling_limit;
302 struct acpi_processor_limit *limit;
305 result = acpi_processor_get_platform_limit(pr);
307 /* Throttling Limit is unsupported */
311 throttling_limit = pr->throttling_platform_limit;
312 if (throttling_limit >= pr->throttling.state_count) {
313 /* Uncorrect Throttling Limit */
317 current_state = pr->throttling.state;
318 if (current_state > throttling_limit) {
320 * The current state can meet the requirement of
321 * _TPC limit. But it is reasonable that OSPM changes
322 * t-states from high to low for better performance.
323 * Of course the limit condition of thermal
324 * and user should be considered.
327 target_state = throttling_limit;
328 if (limit->thermal.tx > target_state)
329 target_state = limit->thermal.tx;
330 if (limit->user.tx > target_state)
331 target_state = limit->user.tx;
332 } else if (current_state == throttling_limit) {
334 * Unnecessary to change the throttling state
339 * If the current state is lower than the limit of _TPC, it
340 * will be forced to switch to the throttling state defined
341 * by throttling_platfor_limit.
342 * Because the previous state meets with the limit condition
343 * of thermal and user, it is unnecessary to check it again.
345 target_state = throttling_limit;
347 return acpi_processor_set_throttling(pr, target_state);
351 * _PTC - Processor Throttling Control (and status) register location
353 static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
356 acpi_status status = 0;
357 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
358 union acpi_object *ptc = NULL;
359 union acpi_object obj = { 0 };
360 struct acpi_processor_throttling *throttling;
362 status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
363 if (ACPI_FAILURE(status)) {
364 if (status != AE_NOT_FOUND) {
365 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
370 ptc = (union acpi_object *)buffer.pointer;
371 if (!ptc || (ptc->type != ACPI_TYPE_PACKAGE)
372 || (ptc->package.count != 2)) {
373 printk(KERN_ERR PREFIX "Invalid _PTC data\n");
382 obj = ptc->package.elements[0];
384 if ((obj.type != ACPI_TYPE_BUFFER)
385 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
386 || (obj.buffer.pointer == NULL)) {
387 printk(KERN_ERR PREFIX
388 "Invalid _PTC data (control_register)\n");
392 memcpy(&pr->throttling.control_register, obj.buffer.pointer,
393 sizeof(struct acpi_ptc_register));
399 obj = ptc->package.elements[1];
401 if ((obj.type != ACPI_TYPE_BUFFER)
402 || (obj.buffer.length < sizeof(struct acpi_ptc_register))
403 || (obj.buffer.pointer == NULL)) {
404 printk(KERN_ERR PREFIX "Invalid _PTC data (status_register)\n");
409 memcpy(&pr->throttling.status_register, obj.buffer.pointer,
410 sizeof(struct acpi_ptc_register));
412 throttling = &pr->throttling;
414 if ((throttling->control_register.bit_width +
415 throttling->control_register.bit_offset) > 32) {
416 printk(KERN_ERR PREFIX "Invalid _PTC control register\n");
421 if ((throttling->status_register.bit_width +
422 throttling->status_register.bit_offset) > 32) {
423 printk(KERN_ERR PREFIX "Invalid _PTC status register\n");
429 kfree(buffer.pointer);
435 * _TSS - Throttling Supported States
437 static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
440 acpi_status status = AE_OK;
441 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
442 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
443 struct acpi_buffer state = { 0, NULL };
444 union acpi_object *tss = NULL;
447 status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
448 if (ACPI_FAILURE(status)) {
449 if (status != AE_NOT_FOUND) {
450 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
455 tss = buffer.pointer;
456 if (!tss || (tss->type != ACPI_TYPE_PACKAGE)) {
457 printk(KERN_ERR PREFIX "Invalid _TSS data\n");
462 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
463 tss->package.count));
465 pr->throttling.state_count = tss->package.count;
466 pr->throttling.states_tss =
467 kmalloc(sizeof(struct acpi_processor_tx_tss) * tss->package.count,
469 if (!pr->throttling.states_tss) {
474 for (i = 0; i < pr->throttling.state_count; i++) {
476 struct acpi_processor_tx_tss *tx =
477 (struct acpi_processor_tx_tss *)&(pr->throttling.
480 state.length = sizeof(struct acpi_processor_tx_tss);
483 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
485 status = acpi_extract_package(&(tss->package.elements[i]),
487 if (ACPI_FAILURE(status)) {
488 ACPI_EXCEPTION((AE_INFO, status, "Invalid _TSS data"));
490 kfree(pr->throttling.states_tss);
494 if (!tx->freqpercentage) {
495 printk(KERN_ERR PREFIX
496 "Invalid _TSS data: freq is zero\n");
498 kfree(pr->throttling.states_tss);
504 kfree(buffer.pointer);
510 * _TSD - T-State Dependencies
512 static int acpi_processor_get_tsd(struct acpi_processor *pr)
515 acpi_status status = AE_OK;
516 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
517 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
518 struct acpi_buffer state = { 0, NULL };
519 union acpi_object *tsd = NULL;
520 struct acpi_tsd_package *pdomain;
521 struct acpi_processor_throttling *pthrottling;
523 pthrottling = &pr->throttling;
524 pthrottling->tsd_valid_flag = 0;
526 status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
527 if (ACPI_FAILURE(status)) {
528 if (status != AE_NOT_FOUND) {
529 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
534 tsd = buffer.pointer;
535 if (!tsd || (tsd->type != ACPI_TYPE_PACKAGE)) {
536 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
541 if (tsd->package.count != 1) {
542 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
547 pdomain = &(pr->throttling.domain_info);
549 state.length = sizeof(struct acpi_tsd_package);
550 state.pointer = pdomain;
552 status = acpi_extract_package(&(tsd->package.elements[0]),
554 if (ACPI_FAILURE(status)) {
555 printk(KERN_ERR PREFIX "Invalid _TSD data\n");
560 if (pdomain->num_entries != ACPI_TSD_REV0_ENTRIES) {
561 printk(KERN_ERR PREFIX "Unknown _TSD:num_entries\n");
566 if (pdomain->revision != ACPI_TSD_REV0_REVISION) {
567 printk(KERN_ERR PREFIX "Unknown _TSD:revision\n");
572 pthrottling = &pr->throttling;
573 pthrottling->tsd_valid_flag = 1;
574 pthrottling->shared_type = pdomain->coord_type;
575 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
577 * If the coordination type is not defined in ACPI spec,
578 * the tsd_valid_flag will be clear and coordination type
579 * will be forecd as DOMAIN_COORD_TYPE_SW_ALL.
581 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL &&
582 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY &&
583 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) {
584 pthrottling->tsd_valid_flag = 0;
585 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
589 kfree(buffer.pointer);
593 /* --------------------------------------------------------------------------
595 -------------------------------------------------------------------------- */
596 static int acpi_processor_get_throttling_fadt(struct acpi_processor *pr)
606 if (!pr->flags.throttling)
609 pr->throttling.state = 0;
611 duty_mask = pr->throttling.state_count - 1;
613 duty_mask <<= pr->throttling.duty_offset;
617 value = inl(pr->throttling.address);
620 * Compute the current throttling state when throttling is enabled
624 duty_value = value & duty_mask;
625 duty_value >>= pr->throttling.duty_offset;
628 state = pr->throttling.state_count - duty_value;
631 pr->throttling.state = state;
635 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
636 "Throttling state is T%d (%d%% throttling applied)\n",
637 state, pr->throttling.states[state].performance));
643 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
644 acpi_integer * value)
646 struct cpuinfo_x86 *c;
647 u64 msr_high, msr_low;
655 if ((c->x86_vendor != X86_VENDOR_INTEL) ||
656 !cpu_has(c, X86_FEATURE_ACPI)) {
657 printk(KERN_ERR PREFIX
658 "HARDWARE addr space,NOT supported yet\n");
662 rdmsr_safe(MSR_IA32_THERM_CONTROL,
663 (u32 *)&msr_low , (u32 *) &msr_high);
664 msr = (msr_high << 32) | msr_low;
665 *value = (acpi_integer) msr;
671 static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
673 struct cpuinfo_x86 *c;
681 if ((c->x86_vendor != X86_VENDOR_INTEL) ||
682 !cpu_has(c, X86_FEATURE_ACPI)) {
683 printk(KERN_ERR PREFIX
684 "HARDWARE addr space,NOT supported yet\n");
687 wrmsr_safe(MSR_IA32_THERM_CONTROL,
688 msr & 0xffffffff, msr >> 32);
694 static int acpi_throttling_rdmsr(struct acpi_processor *pr,
695 acpi_integer * value)
697 printk(KERN_ERR PREFIX
698 "HARDWARE addr space,NOT supported yet\n");
702 static int acpi_throttling_wrmsr(struct acpi_processor *pr, acpi_integer value)
704 printk(KERN_ERR PREFIX
705 "HARDWARE addr space,NOT supported yet\n");
710 static int acpi_read_throttling_status(struct acpi_processor *pr,
713 u32 bit_width, bit_offset;
716 struct acpi_processor_throttling *throttling;
719 throttling = &pr->throttling;
720 switch (throttling->status_register.space_id) {
721 case ACPI_ADR_SPACE_SYSTEM_IO:
723 bit_width = throttling->status_register.bit_width;
724 bit_offset = throttling->status_register.bit_offset;
726 acpi_os_read_port((acpi_io_address) throttling->status_register.
727 address, (u32 *) &ptc_value,
728 (u32) (bit_width + bit_offset));
729 ptc_mask = (1 << bit_width) - 1;
730 *value = (acpi_integer) ((ptc_value >> bit_offset) & ptc_mask);
733 case ACPI_ADR_SPACE_FIXED_HARDWARE:
734 ret = acpi_throttling_rdmsr(pr, value);
737 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
738 (u32) (throttling->status_register.space_id));
743 static int acpi_write_throttling_state(struct acpi_processor *pr,
746 u32 bit_width, bit_offset;
749 struct acpi_processor_throttling *throttling;
752 throttling = &pr->throttling;
753 switch (throttling->control_register.space_id) {
754 case ACPI_ADR_SPACE_SYSTEM_IO:
755 bit_width = throttling->control_register.bit_width;
756 bit_offset = throttling->control_register.bit_offset;
757 ptc_mask = (1 << bit_width) - 1;
758 ptc_value = value & ptc_mask;
760 acpi_os_write_port((acpi_io_address) throttling->
761 control_register.address,
762 (u32) (ptc_value << bit_offset),
763 (u32) (bit_width + bit_offset));
766 case ACPI_ADR_SPACE_FIXED_HARDWARE:
767 ret = acpi_throttling_wrmsr(pr, value);
770 printk(KERN_ERR PREFIX "Unknown addr space %d\n",
771 (u32) (throttling->control_register.space_id));
776 static int acpi_get_throttling_state(struct acpi_processor *pr,
781 for (i = 0; i < pr->throttling.state_count; i++) {
782 struct acpi_processor_tx_tss *tx =
783 (struct acpi_processor_tx_tss *)&(pr->throttling.
785 if (tx->control == value)
791 static int acpi_get_throttling_value(struct acpi_processor *pr,
792 int state, acpi_integer *value)
796 if (state >= 0 && state <= pr->throttling.state_count) {
797 struct acpi_processor_tx_tss *tx =
798 (struct acpi_processor_tx_tss *)&(pr->throttling.
800 *value = tx->control;
806 static int acpi_processor_get_throttling_ptc(struct acpi_processor *pr)
815 if (!pr->flags.throttling)
818 pr->throttling.state = 0;
821 ret = acpi_read_throttling_status(pr, &value);
823 state = acpi_get_throttling_state(pr, value);
824 pr->throttling.state = state;
830 static int acpi_processor_get_throttling(struct acpi_processor *pr)
832 cpumask_var_t saved_mask;
838 if (!pr->flags.throttling)
841 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
845 * Migrate task to the cpu pointed by pr.
847 cpumask_copy(saved_mask, ¤t->cpus_allowed);
848 /* FIXME: use work_on_cpu() */
849 set_cpus_allowed_ptr(current, cpumask_of(pr->id));
850 ret = pr->throttling.acpi_processor_get_throttling(pr);
851 /* restore the previous state */
852 set_cpus_allowed_ptr(current, saved_mask);
853 free_cpumask_var(saved_mask);
858 static int acpi_processor_get_fadt_info(struct acpi_processor *pr)
862 if (!pr->throttling.address) {
863 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
865 } else if (!pr->throttling.duty_width) {
866 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
869 /* TBD: Support duty_cycle values that span bit 4. */
870 else if ((pr->throttling.duty_offset + pr->throttling.duty_width) > 4) {
871 printk(KERN_WARNING PREFIX "duty_cycle spans bit 4\n");
875 pr->throttling.state_count = 1 << acpi_gbl_FADT.duty_width;
878 * Compute state values. Note that throttling displays a linear power
879 * performance relationship (at 50% performance the CPU will consume
880 * 50% power). Values are in 1/10th of a percent to preserve accuracy.
883 step = (1000 / pr->throttling.state_count);
885 for (i = 0; i < pr->throttling.state_count; i++) {
886 pr->throttling.states[i].performance = 1000 - step * i;
887 pr->throttling.states[i].power = 1000 - step * i;
892 static int acpi_processor_set_throttling_fadt(struct acpi_processor *pr,
902 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
905 if (!pr->flags.throttling)
908 if (state == pr->throttling.state)
911 if (state < pr->throttling_platform_limit)
914 * Calculate the duty_value and duty_mask.
917 duty_value = pr->throttling.state_count - state;
919 duty_value <<= pr->throttling.duty_offset;
921 /* Used to clear all duty_value bits */
922 duty_mask = pr->throttling.state_count - 1;
924 duty_mask <<= acpi_gbl_FADT.duty_offset;
925 duty_mask = ~duty_mask;
931 * Disable throttling by writing a 0 to bit 4. Note that we must
932 * turn it off before you can change the duty_value.
934 value = inl(pr->throttling.address);
937 outl(value, pr->throttling.address);
941 * Write the new duty_value and then enable throttling. Note
942 * that a state value of 0 leaves throttling disabled.
947 outl(value, pr->throttling.address);
950 outl(value, pr->throttling.address);
953 pr->throttling.state = state;
957 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
958 "Throttling state set to T%d (%d%%)\n", state,
959 (pr->throttling.states[state].performance ? pr->
960 throttling.states[state].performance / 10 : 0)));
965 static int acpi_processor_set_throttling_ptc(struct acpi_processor *pr,
974 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
977 if (!pr->flags.throttling)
980 if (state == pr->throttling.state)
983 if (state < pr->throttling_platform_limit)
987 ret = acpi_get_throttling_value(pr, state, &value);
989 acpi_write_throttling_state(pr, value);
990 pr->throttling.state = state;
996 int acpi_processor_set_throttling(struct acpi_processor *pr, int state)
998 cpumask_var_t saved_mask;
1001 struct acpi_processor *match_pr;
1002 struct acpi_processor_throttling *p_throttling;
1003 struct throttling_tstate t_state;
1004 cpumask_var_t online_throttling_cpus;
1009 if (!pr->flags.throttling)
1012 if ((state < 0) || (state > (pr->throttling.state_count - 1)))
1015 if (!alloc_cpumask_var(&saved_mask, GFP_KERNEL))
1018 if (!alloc_cpumask_var(&online_throttling_cpus, GFP_KERNEL)) {
1019 free_cpumask_var(saved_mask);
1023 cpumask_copy(saved_mask, ¤t->cpus_allowed);
1024 t_state.target_state = state;
1025 p_throttling = &(pr->throttling);
1026 cpumask_and(online_throttling_cpus, cpu_online_mask,
1027 p_throttling->shared_cpu_map);
1029 * The throttling notifier will be called for every
1030 * affected cpu in order to get one proper T-state.
1031 * The notifier event is THROTTLING_PRECHANGE.
1033 for_each_cpu(i, online_throttling_cpus) {
1035 acpi_processor_throttling_notifier(THROTTLING_PRECHANGE,
1039 * The function of acpi_processor_set_throttling will be called
1040 * to switch T-state. If the coordination type is SW_ALL or HW_ALL,
1041 * it is necessary to call it for every affected cpu. Otherwise
1042 * it can be called only for the cpu pointed by pr.
1044 if (p_throttling->shared_type == DOMAIN_COORD_TYPE_SW_ANY) {
1045 /* FIXME: use work_on_cpu() */
1046 set_cpus_allowed_ptr(current, cpumask_of(pr->id));
1047 ret = p_throttling->acpi_processor_set_throttling(pr,
1048 t_state.target_state);
1051 * When the T-state coordination is SW_ALL or HW_ALL,
1052 * it is necessary to set T-state for every affected
1055 for_each_cpu(i, online_throttling_cpus) {
1056 match_pr = per_cpu(processors, i);
1058 * If the pointer is invalid, we will report the
1059 * error message and continue.
1062 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1063 "Invalid Pointer for CPU %d\n", i));
1067 * If the throttling control is unsupported on CPU i,
1068 * we will report the error message and continue.
1070 if (!match_pr->flags.throttling) {
1071 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1072 "Throttling Controll is unsupported "
1077 /* FIXME: use work_on_cpu() */
1078 set_cpus_allowed_ptr(current, cpumask_of(i));
1079 ret = match_pr->throttling.
1080 acpi_processor_set_throttling(
1081 match_pr, t_state.target_state);
1085 * After the set_throttling is called, the
1086 * throttling notifier is called for every
1087 * affected cpu to update the T-states.
1088 * The notifier event is THROTTLING_POSTCHANGE
1090 for_each_cpu(i, online_throttling_cpus) {
1092 acpi_processor_throttling_notifier(THROTTLING_POSTCHANGE,
1095 /* restore the previous state */
1096 /* FIXME: use work_on_cpu() */
1097 set_cpus_allowed_ptr(current, saved_mask);
1098 free_cpumask_var(online_throttling_cpus);
1099 free_cpumask_var(saved_mask);
1103 int acpi_processor_get_throttling_info(struct acpi_processor *pr)
1106 struct acpi_processor_throttling *pthrottling;
1108 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1109 "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
1110 pr->throttling.address,
1111 pr->throttling.duty_offset,
1112 pr->throttling.duty_width));
1118 * Evaluate _PTC, _TSS and _TPC
1119 * They must all be present or none of them can be used.
1121 if (acpi_processor_get_throttling_control(pr) ||
1122 acpi_processor_get_throttling_states(pr) ||
1123 acpi_processor_get_platform_limit(pr))
1125 pr->throttling.acpi_processor_get_throttling =
1126 &acpi_processor_get_throttling_fadt;
1127 pr->throttling.acpi_processor_set_throttling =
1128 &acpi_processor_set_throttling_fadt;
1129 if (acpi_processor_get_fadt_info(pr))
1132 pr->throttling.acpi_processor_get_throttling =
1133 &acpi_processor_get_throttling_ptc;
1134 pr->throttling.acpi_processor_set_throttling =
1135 &acpi_processor_set_throttling_ptc;
1139 * If TSD package for one CPU can't be parsed successfully, it means
1140 * that this CPU will have no coordination with other CPUs.
1142 if (acpi_processor_get_tsd(pr)) {
1143 pthrottling = &pr->throttling;
1144 pthrottling->tsd_valid_flag = 0;
1145 cpumask_set_cpu(pr->id, pthrottling->shared_cpu_map);
1146 pthrottling->shared_type = DOMAIN_COORD_TYPE_SW_ALL;
1150 * PIIX4 Errata: We don't support throttling on the original PIIX4.
1151 * This shouldn't be an issue as few (if any) mobile systems ever
1154 if (errata.piix4.throttle) {
1155 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1156 "Throttling not supported on PIIX4 A- or B-step\n"));
1160 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
1161 pr->throttling.state_count));
1163 pr->flags.throttling = 1;
1166 * Disable throttling (if enabled). We'll let subsequent policy (e.g.
1167 * thermal) decide to lower performance if it so chooses, but for now
1168 * we'll crank up the speed.
1171 result = acpi_processor_get_throttling(pr);
1175 if (pr->throttling.state) {
1176 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1177 "Disabling throttling (was T%d)\n",
1178 pr->throttling.state));
1179 result = acpi_processor_set_throttling(pr, 0);
1186 pr->flags.throttling = 0;
1191 /* proc interface */
1193 static int acpi_processor_throttling_seq_show(struct seq_file *seq,
1196 struct acpi_processor *pr = seq->private;
1203 if (!(pr->throttling.state_count > 0)) {
1204 seq_puts(seq, "<not supported>\n");
1208 result = acpi_processor_get_throttling(pr);
1212 "Could not determine current throttling state.\n");
1216 seq_printf(seq, "state count: %d\n"
1217 "active state: T%d\n"
1218 "state available: T%d to T%d\n",
1219 pr->throttling.state_count, pr->throttling.state,
1220 pr->throttling_platform_limit,
1221 pr->throttling.state_count - 1);
1223 seq_puts(seq, "states:\n");
1224 if (pr->throttling.acpi_processor_get_throttling ==
1225 acpi_processor_get_throttling_fadt) {
1226 for (i = 0; i < pr->throttling.state_count; i++)
1227 seq_printf(seq, " %cT%d: %02d%%\n",
1228 (i == pr->throttling.state ? '*' : ' '), i,
1229 (pr->throttling.states[i].performance ? pr->
1230 throttling.states[i].performance / 10 : 0));
1232 for (i = 0; i < pr->throttling.state_count; i++)
1233 seq_printf(seq, " %cT%d: %02d%%\n",
1234 (i == pr->throttling.state ? '*' : ' '), i,
1235 (int)pr->throttling.states_tss[i].
1243 static int acpi_processor_throttling_open_fs(struct inode *inode,
1246 return single_open(file, acpi_processor_throttling_seq_show,
1250 static ssize_t acpi_processor_write_throttling(struct file *file,
1251 const char __user * buffer,
1252 size_t count, loff_t * data)
1255 struct seq_file *m = file->private_data;
1256 struct acpi_processor *pr = m->private;
1257 char state_string[5] = "";
1259 size_t state_val = 0;
1260 char tmpbuf[5] = "";
1262 if (!pr || (count > sizeof(state_string) - 1))
1265 if (copy_from_user(state_string, buffer, count))
1268 state_string[count] = '\0';
1269 if ((count > 0) && (state_string[count-1] == '\n'))
1270 state_string[count-1] = '\0';
1272 charp = state_string;
1273 if ((state_string[0] == 't') || (state_string[0] == 'T'))
1276 state_val = simple_strtoul(charp, NULL, 0);
1277 if (state_val >= pr->throttling.state_count)
1280 snprintf(tmpbuf, 5, "%zu", state_val);
1282 if (strcmp(tmpbuf, charp) != 0)
1285 result = acpi_processor_set_throttling(pr, state_val);
1292 const struct file_operations acpi_processor_throttling_fops = {
1293 .owner = THIS_MODULE,
1294 .open = acpi_processor_throttling_open_fs,
1296 .write = acpi_processor_write_throttling,
1297 .llseek = seq_lseek,
1298 .release = single_release,