2 * processor_idle - idle state submodule to 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, 2005 Dominik Brodowski <linux@brodo.de>
7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
8 * - Added processor hotplug support
9 * Copyright (C) 2005 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
10 * - Added support for C3 on SMP
12 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or (at
17 * your option) any later version.
19 * This program is distributed in the hope that it will be useful, but
20 * WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
22 * General Public License for more details.
24 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
26 #define pr_fmt(fmt) "ACPI: " fmt
28 #include <linux/module.h>
29 #include <linux/acpi.h>
30 #include <linux/dmi.h>
31 #include <linux/sched.h> /* need_resched() */
32 #include <linux/tick.h>
33 #include <linux/cpuidle.h>
34 #include <acpi/processor.h>
37 * Include the apic definitions for x86 to have the APIC timer related defines
38 * available also for UP (on SMP it gets magically included via linux/smp.h).
39 * asm/acpi.h is not an option, as it would require more include magic. Also
40 * creating an empty asm-ia64/apic.h would just trade pest vs. cholera.
46 #define ACPI_PROCESSOR_CLASS "processor"
47 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
48 ACPI_MODULE_NAME("processor_idle");
50 static unsigned int max_cstate __read_mostly
= ACPI_PROCESSOR_MAX_POWER
;
51 module_param(max_cstate
, uint
, 0000);
52 static unsigned int nocst __read_mostly
;
53 module_param(nocst
, uint
, 0000);
54 static int bm_check_disable __read_mostly
;
55 module_param(bm_check_disable
, uint
, 0000);
57 static unsigned int latency_factor __read_mostly
= 2;
58 module_param(latency_factor
, uint
, 0644);
60 static DEFINE_PER_CPU(struct cpuidle_device
*, acpi_cpuidle_device
);
62 struct cpuidle_driver acpi_idle_driver
= {
67 #ifdef CONFIG_ACPI_PROCESSOR_CSTATE
69 DEFINE_PER_CPU(struct acpi_processor_cx
* [CPUIDLE_STATE_MAX
], acpi_cstate
);
71 static int disabled_by_idle_boot_param(void)
73 return boot_option_idle_override
== IDLE_POLL
||
74 boot_option_idle_override
== IDLE_HALT
;
78 * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3.
79 * For now disable this. Probably a bug somewhere else.
81 * To skip this limit, boot/load with a large max_cstate limit.
83 static int set_max_cstate(const struct dmi_system_id
*id
)
85 if (max_cstate
> ACPI_PROCESSOR_MAX_POWER
)
88 pr_notice("%s detected - limiting to C%ld max_cstate."
89 " Override with \"processor.max_cstate=%d\"\n", id
->ident
,
90 (long)id
->driver_data
, ACPI_PROCESSOR_MAX_POWER
+ 1);
92 max_cstate
= (long)id
->driver_data
;
97 static const struct dmi_system_id processor_power_dmi_table
[] = {
98 { set_max_cstate
, "Clevo 5600D", {
99 DMI_MATCH(DMI_BIOS_VENDOR
,"Phoenix Technologies LTD"),
100 DMI_MATCH(DMI_BIOS_VERSION
,"SHE845M0.86C.0013.D.0302131307")},
102 { set_max_cstate
, "Pavilion zv5000", {
103 DMI_MATCH(DMI_SYS_VENDOR
, "Hewlett-Packard"),
104 DMI_MATCH(DMI_PRODUCT_NAME
,"Pavilion zv5000 (DS502A#ABA)")},
106 { set_max_cstate
, "Asus L8400B", {
107 DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK Computer Inc."),
108 DMI_MATCH(DMI_PRODUCT_NAME
,"L8400B series Notebook PC")},
115 * Callers should disable interrupts before the call and enable
116 * interrupts after return.
118 static void acpi_safe_halt(void)
120 if (!tif_need_resched()) {
126 #ifdef ARCH_APICTIMER_STOPS_ON_C3
129 * Some BIOS implementations switch to C3 in the published C2 state.
130 * This seems to be a common problem on AMD boxen, but other vendors
131 * are affected too. We pick the most conservative approach: we assume
132 * that the local APIC stops in both C2 and C3.
134 static void lapic_timer_check_state(int state
, struct acpi_processor
*pr
,
135 struct acpi_processor_cx
*cx
)
137 struct acpi_processor_power
*pwr
= &pr
->power
;
138 u8 type
= local_apic_timer_c2_ok
? ACPI_STATE_C3
: ACPI_STATE_C2
;
140 if (cpu_has(&cpu_data(pr
->id
), X86_FEATURE_ARAT
))
143 if (amd_e400_c1e_detected
)
144 type
= ACPI_STATE_C1
;
147 * Check, if one of the previous states already marked the lapic
150 if (pwr
->timer_broadcast_on_state
< state
)
153 if (cx
->type
>= type
)
154 pr
->power
.timer_broadcast_on_state
= state
;
157 static void __lapic_timer_propagate_broadcast(void *arg
)
159 struct acpi_processor
*pr
= (struct acpi_processor
*) arg
;
161 if (pr
->power
.timer_broadcast_on_state
< INT_MAX
)
162 tick_broadcast_enable();
164 tick_broadcast_disable();
167 static void lapic_timer_propagate_broadcast(struct acpi_processor
*pr
)
169 smp_call_function_single(pr
->id
, __lapic_timer_propagate_broadcast
,
173 /* Power(C) State timer broadcast control */
174 static void lapic_timer_state_broadcast(struct acpi_processor
*pr
,
175 struct acpi_processor_cx
*cx
,
178 int state
= cx
- pr
->power
.states
;
180 if (state
>= pr
->power
.timer_broadcast_on_state
) {
182 tick_broadcast_enter();
184 tick_broadcast_exit();
190 static void lapic_timer_check_state(int state
, struct acpi_processor
*pr
,
191 struct acpi_processor_cx
*cstate
) { }
192 static void lapic_timer_propagate_broadcast(struct acpi_processor
*pr
) { }
193 static void lapic_timer_state_broadcast(struct acpi_processor
*pr
,
194 struct acpi_processor_cx
*cx
,
201 #if defined(CONFIG_X86)
202 static void tsc_check_state(int state
)
204 switch (boot_cpu_data
.x86_vendor
) {
206 case X86_VENDOR_INTEL
:
208 * AMD Fam10h TSC will tick in all
209 * C/P/S0/S1 states when this bit is set.
211 if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC
))
216 /* TSC could halt in idle, so notify users */
217 if (state
> ACPI_STATE_C1
)
218 mark_tsc_unstable("TSC halts in idle");
222 static void tsc_check_state(int state
) { return; }
225 static int acpi_processor_get_power_info_fadt(struct acpi_processor
*pr
)
231 /* if info is obtained from pblk/fadt, type equals state */
232 pr
->power
.states
[ACPI_STATE_C2
].type
= ACPI_STATE_C2
;
233 pr
->power
.states
[ACPI_STATE_C3
].type
= ACPI_STATE_C3
;
235 #ifndef CONFIG_HOTPLUG_CPU
237 * Check for P_LVL2_UP flag before entering C2 and above on
240 if ((num_online_cpus() > 1) &&
241 !(acpi_gbl_FADT
.flags
& ACPI_FADT_C2_MP_SUPPORTED
))
245 /* determine C2 and C3 address from pblk */
246 pr
->power
.states
[ACPI_STATE_C2
].address
= pr
->pblk
+ 4;
247 pr
->power
.states
[ACPI_STATE_C3
].address
= pr
->pblk
+ 5;
249 /* determine latencies from FADT */
250 pr
->power
.states
[ACPI_STATE_C2
].latency
= acpi_gbl_FADT
.c2_latency
;
251 pr
->power
.states
[ACPI_STATE_C3
].latency
= acpi_gbl_FADT
.c3_latency
;
254 * FADT specified C2 latency must be less than or equal to
257 if (acpi_gbl_FADT
.c2_latency
> ACPI_PROCESSOR_MAX_C2_LATENCY
) {
258 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
259 "C2 latency too large [%d]\n", acpi_gbl_FADT
.c2_latency
));
261 pr
->power
.states
[ACPI_STATE_C2
].address
= 0;
265 * FADT supplied C3 latency must be less than or equal to
268 if (acpi_gbl_FADT
.c3_latency
> ACPI_PROCESSOR_MAX_C3_LATENCY
) {
269 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
270 "C3 latency too large [%d]\n", acpi_gbl_FADT
.c3_latency
));
272 pr
->power
.states
[ACPI_STATE_C3
].address
= 0;
275 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
276 "lvl2[0x%08x] lvl3[0x%08x]\n",
277 pr
->power
.states
[ACPI_STATE_C2
].address
,
278 pr
->power
.states
[ACPI_STATE_C3
].address
));
283 static int acpi_processor_get_power_info_default(struct acpi_processor
*pr
)
285 if (!pr
->power
.states
[ACPI_STATE_C1
].valid
) {
286 /* set the first C-State to C1 */
287 /* all processors need to support C1 */
288 pr
->power
.states
[ACPI_STATE_C1
].type
= ACPI_STATE_C1
;
289 pr
->power
.states
[ACPI_STATE_C1
].valid
= 1;
290 pr
->power
.states
[ACPI_STATE_C1
].entry_method
= ACPI_CSTATE_HALT
;
292 /* the C0 state only exists as a filler in our array */
293 pr
->power
.states
[ACPI_STATE_C0
].valid
= 1;
297 static int acpi_processor_get_power_info_cst(struct acpi_processor
*pr
)
303 struct acpi_buffer buffer
= { ACPI_ALLOCATE_BUFFER
, NULL
};
304 union acpi_object
*cst
;
311 status
= acpi_evaluate_object(pr
->handle
, "_CST", NULL
, &buffer
);
312 if (ACPI_FAILURE(status
)) {
313 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "No _CST, giving up\n"));
317 cst
= buffer
.pointer
;
319 /* There must be at least 2 elements */
320 if (!cst
|| (cst
->type
!= ACPI_TYPE_PACKAGE
) || cst
->package
.count
< 2) {
321 pr_err("not enough elements in _CST\n");
326 count
= cst
->package
.elements
[0].integer
.value
;
328 /* Validate number of power states. */
329 if (count
< 1 || count
!= cst
->package
.count
- 1) {
330 pr_err("count given by _CST is not valid\n");
335 /* Tell driver that at least _CST is supported. */
336 pr
->flags
.has_cst
= 1;
338 for (i
= 1; i
<= count
; i
++) {
339 union acpi_object
*element
;
340 union acpi_object
*obj
;
341 struct acpi_power_register
*reg
;
342 struct acpi_processor_cx cx
;
344 memset(&cx
, 0, sizeof(cx
));
346 element
= &(cst
->package
.elements
[i
]);
347 if (element
->type
!= ACPI_TYPE_PACKAGE
)
350 if (element
->package
.count
!= 4)
353 obj
= &(element
->package
.elements
[0]);
355 if (obj
->type
!= ACPI_TYPE_BUFFER
)
358 reg
= (struct acpi_power_register
*)obj
->buffer
.pointer
;
360 if (reg
->space_id
!= ACPI_ADR_SPACE_SYSTEM_IO
&&
361 (reg
->space_id
!= ACPI_ADR_SPACE_FIXED_HARDWARE
))
364 /* There should be an easy way to extract an integer... */
365 obj
= &(element
->package
.elements
[1]);
366 if (obj
->type
!= ACPI_TYPE_INTEGER
)
369 cx
.type
= obj
->integer
.value
;
371 * Some buggy BIOSes won't list C1 in _CST -
372 * Let acpi_processor_get_power_info_default() handle them later
374 if (i
== 1 && cx
.type
!= ACPI_STATE_C1
)
377 cx
.address
= reg
->address
;
378 cx
.index
= current_count
+ 1;
380 cx
.entry_method
= ACPI_CSTATE_SYSTEMIO
;
381 if (reg
->space_id
== ACPI_ADR_SPACE_FIXED_HARDWARE
) {
382 if (acpi_processor_ffh_cstate_probe
383 (pr
->id
, &cx
, reg
) == 0) {
384 cx
.entry_method
= ACPI_CSTATE_FFH
;
385 } else if (cx
.type
== ACPI_STATE_C1
) {
387 * C1 is a special case where FIXED_HARDWARE
388 * can be handled in non-MWAIT way as well.
389 * In that case, save this _CST entry info.
390 * Otherwise, ignore this info and continue.
392 cx
.entry_method
= ACPI_CSTATE_HALT
;
393 snprintf(cx
.desc
, ACPI_CX_DESC_LEN
, "ACPI HLT");
397 if (cx
.type
== ACPI_STATE_C1
&&
398 (boot_option_idle_override
== IDLE_NOMWAIT
)) {
400 * In most cases the C1 space_id obtained from
401 * _CST object is FIXED_HARDWARE access mode.
402 * But when the option of idle=halt is added,
403 * the entry_method type should be changed from
404 * CSTATE_FFH to CSTATE_HALT.
405 * When the option of idle=nomwait is added,
406 * the C1 entry_method type should be
409 cx
.entry_method
= ACPI_CSTATE_HALT
;
410 snprintf(cx
.desc
, ACPI_CX_DESC_LEN
, "ACPI HLT");
413 snprintf(cx
.desc
, ACPI_CX_DESC_LEN
, "ACPI IOPORT 0x%x",
417 if (cx
.type
== ACPI_STATE_C1
) {
421 obj
= &(element
->package
.elements
[2]);
422 if (obj
->type
!= ACPI_TYPE_INTEGER
)
425 cx
.latency
= obj
->integer
.value
;
427 obj
= &(element
->package
.elements
[3]);
428 if (obj
->type
!= ACPI_TYPE_INTEGER
)
432 memcpy(&(pr
->power
.states
[current_count
]), &cx
, sizeof(cx
));
435 * We support total ACPI_PROCESSOR_MAX_POWER - 1
436 * (From 1 through ACPI_PROCESSOR_MAX_POWER - 1)
438 if (current_count
>= (ACPI_PROCESSOR_MAX_POWER
- 1)) {
439 pr_warn("Limiting number of power states to max (%d)\n",
440 ACPI_PROCESSOR_MAX_POWER
);
441 pr_warn("Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n");
446 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Found %d power states\n",
449 /* Validate number of power states discovered */
450 if (current_count
< 2)
454 kfree(buffer
.pointer
);
459 static void acpi_processor_power_verify_c3(struct acpi_processor
*pr
,
460 struct acpi_processor_cx
*cx
)
462 static int bm_check_flag
= -1;
463 static int bm_control_flag
= -1;
470 * PIIX4 Erratum #18: We don't support C3 when Type-F (fast)
471 * DMA transfers are used by any ISA device to avoid livelock.
472 * Note that we could disable Type-F DMA (as recommended by
473 * the erratum), but this is known to disrupt certain ISA
474 * devices thus we take the conservative approach.
476 else if (errata
.piix4
.fdma
) {
477 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
478 "C3 not supported on PIIX4 with Type-F DMA\n"));
482 /* All the logic here assumes flags.bm_check is same across all CPUs */
483 if (bm_check_flag
== -1) {
484 /* Determine whether bm_check is needed based on CPU */
485 acpi_processor_power_init_bm_check(&(pr
->flags
), pr
->id
);
486 bm_check_flag
= pr
->flags
.bm_check
;
487 bm_control_flag
= pr
->flags
.bm_control
;
489 pr
->flags
.bm_check
= bm_check_flag
;
490 pr
->flags
.bm_control
= bm_control_flag
;
493 if (pr
->flags
.bm_check
) {
494 if (!pr
->flags
.bm_control
) {
495 if (pr
->flags
.has_cst
!= 1) {
496 /* bus mastering control is necessary */
497 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
498 "C3 support requires BM control\n"));
501 /* Here we enter C3 without bus mastering */
502 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
503 "C3 support without BM control\n"));
508 * WBINVD should be set in fadt, for C3 state to be
509 * supported on when bm_check is not required.
511 if (!(acpi_gbl_FADT
.flags
& ACPI_FADT_WBINVD
)) {
512 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
513 "Cache invalidation should work properly"
514 " for C3 to be enabled on SMP systems\n"));
520 * Otherwise we've met all of our C3 requirements.
521 * Normalize the C3 latency to expidite policy. Enable
522 * checking of bus mastering status (bm_check) so we can
523 * use this in our C3 policy
528 * On older chipsets, BM_RLD needs to be set
529 * in order for Bus Master activity to wake the
530 * system from C3. Newer chipsets handle DMA
531 * during C3 automatically and BM_RLD is a NOP.
532 * In either case, the proper way to
533 * handle BM_RLD is to set it and leave it set.
535 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD
, 1);
540 static int acpi_processor_power_verify(struct acpi_processor
*pr
)
543 unsigned int working
= 0;
545 pr
->power
.timer_broadcast_on_state
= INT_MAX
;
547 for (i
= 1; i
< ACPI_PROCESSOR_MAX_POWER
&& i
<= max_cstate
; i
++) {
548 struct acpi_processor_cx
*cx
= &pr
->power
.states
[i
];
562 acpi_processor_power_verify_c3(pr
, cx
);
568 lapic_timer_check_state(i
, pr
, cx
);
569 tsc_check_state(cx
->type
);
573 lapic_timer_propagate_broadcast(pr
);
578 static int acpi_processor_get_cstate_info(struct acpi_processor
*pr
)
584 /* NOTE: the idle thread may not be running while calling
587 /* Zero initialize all the C-states info. */
588 memset(pr
->power
.states
, 0, sizeof(pr
->power
.states
));
590 result
= acpi_processor_get_power_info_cst(pr
);
591 if (result
== -ENODEV
)
592 result
= acpi_processor_get_power_info_fadt(pr
);
597 acpi_processor_get_power_info_default(pr
);
599 pr
->power
.count
= acpi_processor_power_verify(pr
);
602 * if one state of type C2 or C3 is available, mark this
603 * CPU as being "idle manageable"
605 for (i
= 1; i
< ACPI_PROCESSOR_MAX_POWER
; i
++) {
606 if (pr
->power
.states
[i
].valid
) {
608 if (pr
->power
.states
[i
].type
>= ACPI_STATE_C2
)
617 * acpi_idle_bm_check - checks if bus master activity was detected
619 static int acpi_idle_bm_check(void)
623 if (bm_check_disable
)
626 acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_STATUS
, &bm_status
);
628 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_STATUS
, 1);
630 * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect
631 * the true state of bus mastering activity; forcing us to
632 * manually check the BMIDEA bit of each IDE channel.
634 else if (errata
.piix4
.bmisx
) {
635 if ((inb_p(errata
.piix4
.bmisx
+ 0x02) & 0x01)
636 || (inb_p(errata
.piix4
.bmisx
+ 0x0A) & 0x01))
643 * acpi_idle_do_entry - enter idle state using the appropriate method
646 * Caller disables interrupt before call and enables interrupt after return.
648 static void acpi_idle_do_entry(struct acpi_processor_cx
*cx
)
650 if (cx
->entry_method
== ACPI_CSTATE_FFH
) {
651 /* Call into architectural FFH based C-state */
652 acpi_processor_ffh_cstate_enter(cx
);
653 } else if (cx
->entry_method
== ACPI_CSTATE_HALT
) {
656 /* IO port based C-state */
658 /* Dummy wait op - must do something useless after P_LVL2 read
659 because chipsets cannot guarantee that STPCLK# signal
660 gets asserted in time to freeze execution properly. */
661 inl(acpi_gbl_FADT
.xpm_timer_block
.address
);
666 * acpi_idle_play_dead - enters an ACPI state for long-term idle (i.e. off-lining)
667 * @dev: the target CPU
668 * @index: the index of suggested state
670 static int acpi_idle_play_dead(struct cpuidle_device
*dev
, int index
)
672 struct acpi_processor_cx
*cx
= per_cpu(acpi_cstate
[index
], dev
->cpu
);
674 ACPI_FLUSH_CPU_CACHE();
678 if (cx
->entry_method
== ACPI_CSTATE_HALT
)
680 else if (cx
->entry_method
== ACPI_CSTATE_SYSTEMIO
) {
682 /* See comment in acpi_idle_do_entry() */
683 inl(acpi_gbl_FADT
.xpm_timer_block
.address
);
692 static bool acpi_idle_fallback_to_c1(struct acpi_processor
*pr
)
694 return IS_ENABLED(CONFIG_HOTPLUG_CPU
) && !pr
->flags
.has_cst
&&
695 !(acpi_gbl_FADT
.flags
& ACPI_FADT_C2_MP_SUPPORTED
);
698 static int c3_cpu_count
;
699 static DEFINE_RAW_SPINLOCK(c3_lock
);
702 * acpi_idle_enter_bm - enters C3 with proper BM handling
703 * @pr: Target processor
704 * @cx: Target state context
705 * @timer_bc: Whether or not to change timer mode to broadcast
707 static void acpi_idle_enter_bm(struct acpi_processor
*pr
,
708 struct acpi_processor_cx
*cx
, bool timer_bc
)
710 acpi_unlazy_tlb(smp_processor_id());
713 * Must be done before busmaster disable as we might need to
717 lapic_timer_state_broadcast(pr
, cx
, 1);
721 * bm_check implies we need ARB_DIS
722 * bm_control implies whether we can do ARB_DIS
724 * That leaves a case where bm_check is set and bm_control is
725 * not set. In that case we cannot do much, we enter C3
726 * without doing anything.
728 if (pr
->flags
.bm_control
) {
729 raw_spin_lock(&c3_lock
);
731 /* Disable bus master arbitration when all CPUs are in C3 */
732 if (c3_cpu_count
== num_online_cpus())
733 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE
, 1);
734 raw_spin_unlock(&c3_lock
);
737 acpi_idle_do_entry(cx
);
739 /* Re-enable bus master arbitration */
740 if (pr
->flags
.bm_control
) {
741 raw_spin_lock(&c3_lock
);
742 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE
, 0);
744 raw_spin_unlock(&c3_lock
);
748 lapic_timer_state_broadcast(pr
, cx
, 0);
751 static int acpi_idle_enter(struct cpuidle_device
*dev
,
752 struct cpuidle_driver
*drv
, int index
)
754 struct acpi_processor_cx
*cx
= per_cpu(acpi_cstate
[index
], dev
->cpu
);
755 struct acpi_processor
*pr
;
757 pr
= __this_cpu_read(processors
);
761 if (cx
->type
!= ACPI_STATE_C1
) {
762 if (acpi_idle_fallback_to_c1(pr
) && num_online_cpus() > 1) {
763 index
= CPUIDLE_DRIVER_STATE_START
;
764 cx
= per_cpu(acpi_cstate
[index
], dev
->cpu
);
765 } else if (cx
->type
== ACPI_STATE_C3
&& pr
->flags
.bm_check
) {
766 if (cx
->bm_sts_skip
|| !acpi_idle_bm_check()) {
767 acpi_idle_enter_bm(pr
, cx
, true);
769 } else if (drv
->safe_state_index
>= 0) {
770 index
= drv
->safe_state_index
;
771 cx
= per_cpu(acpi_cstate
[index
], dev
->cpu
);
779 lapic_timer_state_broadcast(pr
, cx
, 1);
781 if (cx
->type
== ACPI_STATE_C3
)
782 ACPI_FLUSH_CPU_CACHE();
784 acpi_idle_do_entry(cx
);
786 lapic_timer_state_broadcast(pr
, cx
, 0);
791 static void acpi_idle_enter_freeze(struct cpuidle_device
*dev
,
792 struct cpuidle_driver
*drv
, int index
)
794 struct acpi_processor_cx
*cx
= per_cpu(acpi_cstate
[index
], dev
->cpu
);
796 if (cx
->type
== ACPI_STATE_C3
) {
797 struct acpi_processor
*pr
= __this_cpu_read(processors
);
802 if (pr
->flags
.bm_check
) {
803 acpi_idle_enter_bm(pr
, cx
, false);
806 ACPI_FLUSH_CPU_CACHE();
809 acpi_idle_do_entry(cx
);
812 static int acpi_processor_setup_cpuidle_cx(struct acpi_processor
*pr
,
813 struct cpuidle_device
*dev
)
815 int i
, count
= CPUIDLE_DRIVER_STATE_START
;
816 struct acpi_processor_cx
*cx
;
821 for (i
= 1; i
< ACPI_PROCESSOR_MAX_POWER
&& i
<= max_cstate
; i
++) {
822 cx
= &pr
->power
.states
[i
];
827 per_cpu(acpi_cstate
[count
], dev
->cpu
) = cx
;
830 if (count
== CPUIDLE_STATE_MAX
)
840 static int acpi_processor_setup_cstates(struct acpi_processor
*pr
)
842 int i
, count
= CPUIDLE_DRIVER_STATE_START
;
843 struct acpi_processor_cx
*cx
;
844 struct cpuidle_state
*state
;
845 struct cpuidle_driver
*drv
= &acpi_idle_driver
;
850 for (i
= 1; i
< ACPI_PROCESSOR_MAX_POWER
&& i
<= max_cstate
; i
++) {
851 cx
= &pr
->power
.states
[i
];
856 state
= &drv
->states
[count
];
857 snprintf(state
->name
, CPUIDLE_NAME_LEN
, "C%d", i
);
858 strlcpy(state
->desc
, cx
->desc
, CPUIDLE_DESC_LEN
);
859 state
->exit_latency
= cx
->latency
;
860 state
->target_residency
= cx
->latency
* latency_factor
;
861 state
->enter
= acpi_idle_enter
;
864 if (cx
->type
== ACPI_STATE_C1
|| cx
->type
== ACPI_STATE_C2
) {
865 state
->enter_dead
= acpi_idle_play_dead
;
866 drv
->safe_state_index
= count
;
869 * Halt-induced C1 is not good for ->enter_freeze, because it
870 * re-enables interrupts on exit. Moreover, C1 is generally not
871 * particularly interesting from the suspend-to-idle angle, so
872 * avoid C1 and the situations in which we may need to fall back
875 if (cx
->type
!= ACPI_STATE_C1
&& !acpi_idle_fallback_to_c1(pr
))
876 state
->enter_freeze
= acpi_idle_enter_freeze
;
879 if (count
== CPUIDLE_STATE_MAX
)
883 drv
->state_count
= count
;
891 static inline void acpi_processor_cstate_first_run_checks(void)
894 static int first_run
;
898 dmi_check_system(processor_power_dmi_table
);
899 max_cstate
= acpi_processor_cstate_check(max_cstate
);
900 if (max_cstate
< ACPI_C_STATES_MAX
)
901 pr_notice("ACPI: processor limited to max C-state %d\n",
905 if (acpi_gbl_FADT
.cst_control
&& !nocst
) {
906 status
= acpi_os_write_port(acpi_gbl_FADT
.smi_command
,
907 acpi_gbl_FADT
.cst_control
, 8);
908 if (ACPI_FAILURE(status
))
909 ACPI_EXCEPTION((AE_INFO
, status
,
910 "Notifying BIOS of _CST ability failed"));
915 static inline int disabled_by_idle_boot_param(void) { return 0; }
916 static inline void acpi_processor_cstate_first_run_checks(void) { }
917 static int acpi_processor_get_cstate_info(struct acpi_processor
*pr
)
922 static int acpi_processor_setup_cpuidle_cx(struct acpi_processor
*pr
,
923 struct cpuidle_device
*dev
)
928 static int acpi_processor_setup_cstates(struct acpi_processor
*pr
)
933 #endif /* CONFIG_ACPI_PROCESSOR_CSTATE */
935 struct acpi_lpi_states_array
{
937 unsigned int composite_states_size
;
938 struct acpi_lpi_state
*entries
;
939 struct acpi_lpi_state
*composite_states
[ACPI_PROCESSOR_MAX_POWER
];
942 static int obj_get_integer(union acpi_object
*obj
, u32
*value
)
944 if (obj
->type
!= ACPI_TYPE_INTEGER
)
947 *value
= obj
->integer
.value
;
951 static int acpi_processor_evaluate_lpi(acpi_handle handle
,
952 struct acpi_lpi_states_array
*info
)
956 int pkg_count
, state_idx
= 1, loop
;
957 struct acpi_buffer buffer
= { ACPI_ALLOCATE_BUFFER
, NULL
};
958 union acpi_object
*lpi_data
;
959 struct acpi_lpi_state
*lpi_state
;
961 status
= acpi_evaluate_object(handle
, "_LPI", NULL
, &buffer
);
962 if (ACPI_FAILURE(status
)) {
963 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "No _LPI, giving up\n"));
967 lpi_data
= buffer
.pointer
;
969 /* There must be at least 4 elements = 3 elements + 1 package */
970 if (!lpi_data
|| lpi_data
->type
!= ACPI_TYPE_PACKAGE
||
971 lpi_data
->package
.count
< 4) {
972 pr_debug("not enough elements in _LPI\n");
977 pkg_count
= lpi_data
->package
.elements
[2].integer
.value
;
979 /* Validate number of power states. */
980 if (pkg_count
< 1 || pkg_count
!= lpi_data
->package
.count
- 3) {
981 pr_debug("count given by _LPI is not valid\n");
986 lpi_state
= kcalloc(pkg_count
, sizeof(*lpi_state
), GFP_KERNEL
);
992 info
->size
= pkg_count
;
993 info
->entries
= lpi_state
;
995 /* LPI States start at index 3 */
996 for (loop
= 3; state_idx
<= pkg_count
; loop
++, state_idx
++, lpi_state
++) {
997 union acpi_object
*element
, *pkg_elem
, *obj
;
999 element
= &lpi_data
->package
.elements
[loop
];
1000 if (element
->type
!= ACPI_TYPE_PACKAGE
|| element
->package
.count
< 7)
1003 pkg_elem
= element
->package
.elements
;
1006 if (obj
->type
== ACPI_TYPE_BUFFER
) {
1007 struct acpi_power_register
*reg
;
1009 reg
= (struct acpi_power_register
*)obj
->buffer
.pointer
;
1010 if (reg
->space_id
!= ACPI_ADR_SPACE_SYSTEM_IO
&&
1011 reg
->space_id
!= ACPI_ADR_SPACE_FIXED_HARDWARE
)
1014 lpi_state
->address
= reg
->address
;
1015 lpi_state
->entry_method
=
1016 reg
->space_id
== ACPI_ADR_SPACE_FIXED_HARDWARE
?
1017 ACPI_CSTATE_FFH
: ACPI_CSTATE_SYSTEMIO
;
1018 } else if (obj
->type
== ACPI_TYPE_INTEGER
) {
1019 lpi_state
->entry_method
= ACPI_CSTATE_INTEGER
;
1020 lpi_state
->address
= obj
->integer
.value
;
1025 /* elements[7,8] skipped for now i.e. Residency/Usage counter*/
1028 if (obj
->type
== ACPI_TYPE_STRING
)
1029 strlcpy(lpi_state
->desc
, obj
->string
.pointer
,
1032 lpi_state
->index
= state_idx
;
1033 if (obj_get_integer(pkg_elem
+ 0, &lpi_state
->min_residency
)) {
1034 pr_debug("No min. residency found, assuming 10 us\n");
1035 lpi_state
->min_residency
= 10;
1038 if (obj_get_integer(pkg_elem
+ 1, &lpi_state
->wake_latency
)) {
1039 pr_debug("No wakeup residency found, assuming 10 us\n");
1040 lpi_state
->wake_latency
= 10;
1043 if (obj_get_integer(pkg_elem
+ 2, &lpi_state
->flags
))
1044 lpi_state
->flags
= 0;
1046 if (obj_get_integer(pkg_elem
+ 3, &lpi_state
->arch_flags
))
1047 lpi_state
->arch_flags
= 0;
1049 if (obj_get_integer(pkg_elem
+ 4, &lpi_state
->res_cnt_freq
))
1050 lpi_state
->res_cnt_freq
= 1;
1052 if (obj_get_integer(pkg_elem
+ 5, &lpi_state
->enable_parent_state
))
1053 lpi_state
->enable_parent_state
= 0;
1056 acpi_handle_debug(handle
, "Found %d power states\n", state_idx
);
1058 kfree(buffer
.pointer
);
1063 * flat_state_cnt - the number of composite LPI states after the process of flattening
1065 static int flat_state_cnt
;
1068 * combine_lpi_states - combine local and parent LPI states to form a composite LPI state
1070 * @local: local LPI state
1071 * @parent: parent LPI state
1072 * @result: composite LPI state
1074 static bool combine_lpi_states(struct acpi_lpi_state
*local
,
1075 struct acpi_lpi_state
*parent
,
1076 struct acpi_lpi_state
*result
)
1078 if (parent
->entry_method
== ACPI_CSTATE_INTEGER
) {
1079 if (!parent
->address
) /* 0 means autopromotable */
1081 result
->address
= local
->address
+ parent
->address
;
1083 result
->address
= parent
->address
;
1086 result
->min_residency
= max(local
->min_residency
, parent
->min_residency
);
1087 result
->wake_latency
= local
->wake_latency
+ parent
->wake_latency
;
1088 result
->enable_parent_state
= parent
->enable_parent_state
;
1089 result
->entry_method
= local
->entry_method
;
1091 result
->flags
= parent
->flags
;
1092 result
->arch_flags
= parent
->arch_flags
;
1093 result
->index
= parent
->index
;
1095 strlcpy(result
->desc
, local
->desc
, ACPI_CX_DESC_LEN
);
1096 strlcat(result
->desc
, "+", ACPI_CX_DESC_LEN
);
1097 strlcat(result
->desc
, parent
->desc
, ACPI_CX_DESC_LEN
);
1101 #define ACPI_LPI_STATE_FLAGS_ENABLED BIT(0)
1103 static void stash_composite_state(struct acpi_lpi_states_array
*curr_level
,
1104 struct acpi_lpi_state
*t
)
1106 curr_level
->composite_states
[curr_level
->composite_states_size
++] = t
;
1109 static int flatten_lpi_states(struct acpi_processor
*pr
,
1110 struct acpi_lpi_states_array
*curr_level
,
1111 struct acpi_lpi_states_array
*prev_level
)
1113 int i
, j
, state_count
= curr_level
->size
;
1114 struct acpi_lpi_state
*p
, *t
= curr_level
->entries
;
1116 curr_level
->composite_states_size
= 0;
1117 for (j
= 0; j
< state_count
; j
++, t
++) {
1118 struct acpi_lpi_state
*flpi
;
1120 if (!(t
->flags
& ACPI_LPI_STATE_FLAGS_ENABLED
))
1123 if (flat_state_cnt
>= ACPI_PROCESSOR_MAX_POWER
) {
1124 pr_warn("Limiting number of LPI states to max (%d)\n",
1125 ACPI_PROCESSOR_MAX_POWER
);
1126 pr_warn("Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n");
1130 flpi
= &pr
->power
.lpi_states
[flat_state_cnt
];
1132 if (!prev_level
) { /* leaf/processor node */
1133 memcpy(flpi
, t
, sizeof(*t
));
1134 stash_composite_state(curr_level
, flpi
);
1139 for (i
= 0; i
< prev_level
->composite_states_size
; i
++) {
1140 p
= prev_level
->composite_states
[i
];
1141 if (t
->index
<= p
->enable_parent_state
&&
1142 combine_lpi_states(p
, t
, flpi
)) {
1143 stash_composite_state(curr_level
, flpi
);
1150 kfree(curr_level
->entries
);
1154 static int acpi_processor_get_lpi_info(struct acpi_processor
*pr
)
1158 acpi_handle handle
= pr
->handle
, pr_ahandle
;
1159 struct acpi_device
*d
= NULL
;
1160 struct acpi_lpi_states_array info
[2], *tmp
, *prev
, *curr
;
1162 if (!osc_pc_lpi_support_confirmed
)
1165 if (!acpi_has_method(handle
, "_LPI"))
1171 handle
= pr
->handle
;
1172 ret
= acpi_processor_evaluate_lpi(handle
, prev
);
1175 flatten_lpi_states(pr
, prev
, NULL
);
1177 status
= acpi_get_parent(handle
, &pr_ahandle
);
1178 while (ACPI_SUCCESS(status
)) {
1179 acpi_bus_get_device(pr_ahandle
, &d
);
1180 handle
= pr_ahandle
;
1182 if (strcmp(acpi_device_hid(d
), ACPI_PROCESSOR_CONTAINER_HID
))
1185 /* can be optional ? */
1186 if (!acpi_has_method(handle
, "_LPI"))
1189 ret
= acpi_processor_evaluate_lpi(handle
, curr
);
1193 /* flatten all the LPI states in this level of hierarchy */
1194 flatten_lpi_states(pr
, curr
, prev
);
1196 tmp
= prev
, prev
= curr
, curr
= tmp
;
1198 status
= acpi_get_parent(handle
, &pr_ahandle
);
1201 pr
->power
.count
= flat_state_cnt
;
1202 /* reset the index after flattening */
1203 for (i
= 0; i
< pr
->power
.count
; i
++)
1204 pr
->power
.lpi_states
[i
].index
= i
;
1206 /* Tell driver that _LPI is supported. */
1207 pr
->flags
.has_lpi
= 1;
1208 pr
->flags
.power
= 1;
1213 int __weak
acpi_processor_ffh_lpi_probe(unsigned int cpu
)
1218 int __weak
acpi_processor_ffh_lpi_enter(struct acpi_lpi_state
*lpi
)
1224 * acpi_idle_lpi_enter - enters an ACPI any LPI state
1225 * @dev: the target CPU
1226 * @drv: cpuidle driver containing cpuidle state info
1227 * @index: index of target state
1229 * Return: 0 for success or negative value for error
1231 static int acpi_idle_lpi_enter(struct cpuidle_device
*dev
,
1232 struct cpuidle_driver
*drv
, int index
)
1234 struct acpi_processor
*pr
;
1235 struct acpi_lpi_state
*lpi
;
1237 pr
= __this_cpu_read(processors
);
1242 lpi
= &pr
->power
.lpi_states
[index
];
1243 if (lpi
->entry_method
== ACPI_CSTATE_FFH
)
1244 return acpi_processor_ffh_lpi_enter(lpi
);
1249 static int acpi_processor_setup_lpi_states(struct acpi_processor
*pr
)
1252 struct acpi_lpi_state
*lpi
;
1253 struct cpuidle_state
*state
;
1254 struct cpuidle_driver
*drv
= &acpi_idle_driver
;
1256 if (!pr
->flags
.has_lpi
)
1259 for (i
= 0; i
< pr
->power
.count
&& i
< CPUIDLE_STATE_MAX
; i
++) {
1260 lpi
= &pr
->power
.lpi_states
[i
];
1262 state
= &drv
->states
[i
];
1263 snprintf(state
->name
, CPUIDLE_NAME_LEN
, "LPI-%d", i
);
1264 strlcpy(state
->desc
, lpi
->desc
, CPUIDLE_DESC_LEN
);
1265 state
->exit_latency
= lpi
->wake_latency
;
1266 state
->target_residency
= lpi
->min_residency
;
1267 if (lpi
->arch_flags
)
1268 state
->flags
|= CPUIDLE_FLAG_TIMER_STOP
;
1269 state
->enter
= acpi_idle_lpi_enter
;
1270 drv
->safe_state_index
= i
;
1273 drv
->state_count
= i
;
1279 * acpi_processor_setup_cpuidle_states- prepares and configures cpuidle
1280 * global state data i.e. idle routines
1282 * @pr: the ACPI processor
1284 static int acpi_processor_setup_cpuidle_states(struct acpi_processor
*pr
)
1287 struct cpuidle_driver
*drv
= &acpi_idle_driver
;
1289 if (!pr
->flags
.power_setup_done
|| !pr
->flags
.power
)
1292 drv
->safe_state_index
= -1;
1293 for (i
= CPUIDLE_DRIVER_STATE_START
; i
< CPUIDLE_STATE_MAX
; i
++) {
1294 drv
->states
[i
].name
[0] = '\0';
1295 drv
->states
[i
].desc
[0] = '\0';
1298 if (pr
->flags
.has_lpi
)
1299 return acpi_processor_setup_lpi_states(pr
);
1301 return acpi_processor_setup_cstates(pr
);
1305 * acpi_processor_setup_cpuidle_dev - prepares and configures CPUIDLE
1306 * device i.e. per-cpu data
1308 * @pr: the ACPI processor
1309 * @dev : the cpuidle device
1311 static int acpi_processor_setup_cpuidle_dev(struct acpi_processor
*pr
,
1312 struct cpuidle_device
*dev
)
1314 if (!pr
->flags
.power_setup_done
|| !pr
->flags
.power
|| !dev
)
1318 if (pr
->flags
.has_lpi
)
1319 return acpi_processor_ffh_lpi_probe(pr
->id
);
1321 return acpi_processor_setup_cpuidle_cx(pr
, dev
);
1324 static int acpi_processor_get_power_info(struct acpi_processor
*pr
)
1328 ret
= acpi_processor_get_lpi_info(pr
);
1330 ret
= acpi_processor_get_cstate_info(pr
);
1335 int acpi_processor_hotplug(struct acpi_processor
*pr
)
1338 struct cpuidle_device
*dev
;
1340 if (disabled_by_idle_boot_param())
1343 if (!pr
->flags
.power_setup_done
)
1346 dev
= per_cpu(acpi_cpuidle_device
, pr
->id
);
1347 cpuidle_pause_and_lock();
1348 cpuidle_disable_device(dev
);
1349 ret
= acpi_processor_get_power_info(pr
);
1350 if (!ret
&& pr
->flags
.power
) {
1351 acpi_processor_setup_cpuidle_dev(pr
, dev
);
1352 ret
= cpuidle_enable_device(dev
);
1354 cpuidle_resume_and_unlock();
1359 int acpi_processor_power_state_has_changed(struct acpi_processor
*pr
)
1362 struct acpi_processor
*_pr
;
1363 struct cpuidle_device
*dev
;
1365 if (disabled_by_idle_boot_param())
1368 if (!pr
->flags
.power_setup_done
)
1372 * FIXME: Design the ACPI notification to make it once per
1373 * system instead of once per-cpu. This condition is a hack
1374 * to make the code that updates C-States be called once.
1377 if (pr
->id
== 0 && cpuidle_get_driver() == &acpi_idle_driver
) {
1379 /* Protect against cpu-hotplug */
1381 cpuidle_pause_and_lock();
1383 /* Disable all cpuidle devices */
1384 for_each_online_cpu(cpu
) {
1385 _pr
= per_cpu(processors
, cpu
);
1386 if (!_pr
|| !_pr
->flags
.power_setup_done
)
1388 dev
= per_cpu(acpi_cpuidle_device
, cpu
);
1389 cpuidle_disable_device(dev
);
1392 /* Populate Updated C-state information */
1393 acpi_processor_get_power_info(pr
);
1394 acpi_processor_setup_cpuidle_states(pr
);
1396 /* Enable all cpuidle devices */
1397 for_each_online_cpu(cpu
) {
1398 _pr
= per_cpu(processors
, cpu
);
1399 if (!_pr
|| !_pr
->flags
.power_setup_done
)
1401 acpi_processor_get_power_info(_pr
);
1402 if (_pr
->flags
.power
) {
1403 dev
= per_cpu(acpi_cpuidle_device
, cpu
);
1404 acpi_processor_setup_cpuidle_dev(_pr
, dev
);
1405 cpuidle_enable_device(dev
);
1408 cpuidle_resume_and_unlock();
1415 static int acpi_processor_registered
;
1417 int acpi_processor_power_init(struct acpi_processor
*pr
)
1420 struct cpuidle_device
*dev
;
1422 if (disabled_by_idle_boot_param())
1425 acpi_processor_cstate_first_run_checks();
1427 if (!acpi_processor_get_power_info(pr
))
1428 pr
->flags
.power_setup_done
= 1;
1431 * Install the idle handler if processor power management is supported.
1432 * Note that we use previously set idle handler will be used on
1433 * platforms that only support C1.
1435 if (pr
->flags
.power
) {
1436 /* Register acpi_idle_driver if not already registered */
1437 if (!acpi_processor_registered
) {
1438 acpi_processor_setup_cpuidle_states(pr
);
1439 retval
= cpuidle_register_driver(&acpi_idle_driver
);
1442 pr_debug("%s registered with cpuidle\n",
1443 acpi_idle_driver
.name
);
1446 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
1449 per_cpu(acpi_cpuidle_device
, pr
->id
) = dev
;
1451 acpi_processor_setup_cpuidle_dev(pr
, dev
);
1453 /* Register per-cpu cpuidle_device. Cpuidle driver
1454 * must already be registered before registering device
1456 retval
= cpuidle_register_device(dev
);
1458 if (acpi_processor_registered
== 0)
1459 cpuidle_unregister_driver(&acpi_idle_driver
);
1462 acpi_processor_registered
++;
1467 int acpi_processor_power_exit(struct acpi_processor
*pr
)
1469 struct cpuidle_device
*dev
= per_cpu(acpi_cpuidle_device
, pr
->id
);
1471 if (disabled_by_idle_boot_param())
1474 if (pr
->flags
.power
) {
1475 cpuidle_unregister_device(dev
);
1476 acpi_processor_registered
--;
1477 if (acpi_processor_registered
== 0)
1478 cpuidle_unregister_driver(&acpi_idle_driver
);
1481 pr
->flags
.power_setup_done
= 0;