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 <linux/cpu.h>
35 #include <acpi/processor.h>
38 * Include the apic definitions for x86 to have the APIC timer related defines
39 * available also for UP (on SMP it gets magically included via linux/smp.h).
40 * asm/acpi.h is not an option, as it would require more include magic. Also
41 * creating an empty asm-ia64/apic.h would just trade pest vs. cholera.
47 #define ACPI_PROCESSOR_CLASS "processor"
48 #define _COMPONENT ACPI_PROCESSOR_COMPONENT
49 ACPI_MODULE_NAME("processor_idle");
51 #define ACPI_IDLE_STATE_START (IS_ENABLED(CONFIG_ARCH_HAS_CPU_RELAX) ? 1 : 0)
53 static unsigned int max_cstate __read_mostly
= ACPI_PROCESSOR_MAX_POWER
;
54 module_param(max_cstate
, uint
, 0000);
55 static unsigned int nocst __read_mostly
;
56 module_param(nocst
, uint
, 0000);
57 static int bm_check_disable __read_mostly
;
58 module_param(bm_check_disable
, uint
, 0000);
60 static unsigned int latency_factor __read_mostly
= 2;
61 module_param(latency_factor
, uint
, 0644);
63 static DEFINE_PER_CPU(struct cpuidle_device
*, acpi_cpuidle_device
);
65 struct cpuidle_driver acpi_idle_driver
= {
70 #ifdef CONFIG_ACPI_PROCESSOR_CSTATE
72 DEFINE_PER_CPU(struct acpi_processor_cx
* [CPUIDLE_STATE_MAX
], acpi_cstate
);
74 static int disabled_by_idle_boot_param(void)
76 return boot_option_idle_override
== IDLE_POLL
||
77 boot_option_idle_override
== IDLE_HALT
;
81 * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3.
82 * For now disable this. Probably a bug somewhere else.
84 * To skip this limit, boot/load with a large max_cstate limit.
86 static int set_max_cstate(const struct dmi_system_id
*id
)
88 if (max_cstate
> ACPI_PROCESSOR_MAX_POWER
)
91 pr_notice("%s detected - limiting to C%ld max_cstate."
92 " Override with \"processor.max_cstate=%d\"\n", id
->ident
,
93 (long)id
->driver_data
, ACPI_PROCESSOR_MAX_POWER
+ 1);
95 max_cstate
= (long)id
->driver_data
;
100 static const struct dmi_system_id processor_power_dmi_table
[] = {
101 { set_max_cstate
, "Clevo 5600D", {
102 DMI_MATCH(DMI_BIOS_VENDOR
,"Phoenix Technologies LTD"),
103 DMI_MATCH(DMI_BIOS_VERSION
,"SHE845M0.86C.0013.D.0302131307")},
105 { set_max_cstate
, "Pavilion zv5000", {
106 DMI_MATCH(DMI_SYS_VENDOR
, "Hewlett-Packard"),
107 DMI_MATCH(DMI_PRODUCT_NAME
,"Pavilion zv5000 (DS502A#ABA)")},
109 { set_max_cstate
, "Asus L8400B", {
110 DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK Computer Inc."),
111 DMI_MATCH(DMI_PRODUCT_NAME
,"L8400B series Notebook PC")},
118 * Callers should disable interrupts before the call and enable
119 * interrupts after return.
121 static void __cpuidle
acpi_safe_halt(void)
123 if (!tif_need_resched()) {
129 #ifdef ARCH_APICTIMER_STOPS_ON_C3
132 * Some BIOS implementations switch to C3 in the published C2 state.
133 * This seems to be a common problem on AMD boxen, but other vendors
134 * are affected too. We pick the most conservative approach: we assume
135 * that the local APIC stops in both C2 and C3.
137 static void lapic_timer_check_state(int state
, struct acpi_processor
*pr
,
138 struct acpi_processor_cx
*cx
)
140 struct acpi_processor_power
*pwr
= &pr
->power
;
141 u8 type
= local_apic_timer_c2_ok
? ACPI_STATE_C3
: ACPI_STATE_C2
;
143 if (cpu_has(&cpu_data(pr
->id
), X86_FEATURE_ARAT
))
146 if (boot_cpu_has_bug(X86_BUG_AMD_APIC_C1E
))
147 type
= ACPI_STATE_C1
;
150 * Check, if one of the previous states already marked the lapic
153 if (pwr
->timer_broadcast_on_state
< state
)
156 if (cx
->type
>= type
)
157 pr
->power
.timer_broadcast_on_state
= state
;
160 static void __lapic_timer_propagate_broadcast(void *arg
)
162 struct acpi_processor
*pr
= (struct acpi_processor
*) arg
;
164 if (pr
->power
.timer_broadcast_on_state
< INT_MAX
)
165 tick_broadcast_enable();
167 tick_broadcast_disable();
170 static void lapic_timer_propagate_broadcast(struct acpi_processor
*pr
)
172 smp_call_function_single(pr
->id
, __lapic_timer_propagate_broadcast
,
176 /* Power(C) State timer broadcast control */
177 static void lapic_timer_state_broadcast(struct acpi_processor
*pr
,
178 struct acpi_processor_cx
*cx
,
181 int state
= cx
- pr
->power
.states
;
183 if (state
>= pr
->power
.timer_broadcast_on_state
) {
185 tick_broadcast_enter();
187 tick_broadcast_exit();
193 static void lapic_timer_check_state(int state
, struct acpi_processor
*pr
,
194 struct acpi_processor_cx
*cstate
) { }
195 static void lapic_timer_propagate_broadcast(struct acpi_processor
*pr
) { }
196 static void lapic_timer_state_broadcast(struct acpi_processor
*pr
,
197 struct acpi_processor_cx
*cx
,
204 #if defined(CONFIG_X86)
205 static void tsc_check_state(int state
)
207 switch (boot_cpu_data
.x86_vendor
) {
208 case X86_VENDOR_HYGON
:
210 case X86_VENDOR_INTEL
:
211 case X86_VENDOR_CENTAUR
:
213 * AMD Fam10h TSC will tick in all
214 * C/P/S0/S1 states when this bit is set.
216 if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC
))
221 /* TSC could halt in idle, so notify users */
222 if (state
> ACPI_STATE_C1
)
223 mark_tsc_unstable("TSC halts in idle");
227 static void tsc_check_state(int state
) { return; }
230 static int acpi_processor_get_power_info_fadt(struct acpi_processor
*pr
)
236 /* if info is obtained from pblk/fadt, type equals state */
237 pr
->power
.states
[ACPI_STATE_C2
].type
= ACPI_STATE_C2
;
238 pr
->power
.states
[ACPI_STATE_C3
].type
= ACPI_STATE_C3
;
240 #ifndef CONFIG_HOTPLUG_CPU
242 * Check for P_LVL2_UP flag before entering C2 and above on
245 if ((num_online_cpus() > 1) &&
246 !(acpi_gbl_FADT
.flags
& ACPI_FADT_C2_MP_SUPPORTED
))
250 /* determine C2 and C3 address from pblk */
251 pr
->power
.states
[ACPI_STATE_C2
].address
= pr
->pblk
+ 4;
252 pr
->power
.states
[ACPI_STATE_C3
].address
= pr
->pblk
+ 5;
254 /* determine latencies from FADT */
255 pr
->power
.states
[ACPI_STATE_C2
].latency
= acpi_gbl_FADT
.c2_latency
;
256 pr
->power
.states
[ACPI_STATE_C3
].latency
= acpi_gbl_FADT
.c3_latency
;
259 * FADT specified C2 latency must be less than or equal to
262 if (acpi_gbl_FADT
.c2_latency
> ACPI_PROCESSOR_MAX_C2_LATENCY
) {
263 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
264 "C2 latency too large [%d]\n", acpi_gbl_FADT
.c2_latency
));
266 pr
->power
.states
[ACPI_STATE_C2
].address
= 0;
270 * FADT supplied C3 latency must be less than or equal to
273 if (acpi_gbl_FADT
.c3_latency
> ACPI_PROCESSOR_MAX_C3_LATENCY
) {
274 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
275 "C3 latency too large [%d]\n", acpi_gbl_FADT
.c3_latency
));
277 pr
->power
.states
[ACPI_STATE_C3
].address
= 0;
280 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
281 "lvl2[0x%08x] lvl3[0x%08x]\n",
282 pr
->power
.states
[ACPI_STATE_C2
].address
,
283 pr
->power
.states
[ACPI_STATE_C3
].address
));
285 snprintf(pr
->power
.states
[ACPI_STATE_C2
].desc
,
286 ACPI_CX_DESC_LEN
, "ACPI P_LVL2 IOPORT 0x%x",
287 pr
->power
.states
[ACPI_STATE_C2
].address
);
288 snprintf(pr
->power
.states
[ACPI_STATE_C3
].desc
,
289 ACPI_CX_DESC_LEN
, "ACPI P_LVL3 IOPORT 0x%x",
290 pr
->power
.states
[ACPI_STATE_C3
].address
);
295 static int acpi_processor_get_power_info_default(struct acpi_processor
*pr
)
297 if (!pr
->power
.states
[ACPI_STATE_C1
].valid
) {
298 /* set the first C-State to C1 */
299 /* all processors need to support C1 */
300 pr
->power
.states
[ACPI_STATE_C1
].type
= ACPI_STATE_C1
;
301 pr
->power
.states
[ACPI_STATE_C1
].valid
= 1;
302 pr
->power
.states
[ACPI_STATE_C1
].entry_method
= ACPI_CSTATE_HALT
;
304 snprintf(pr
->power
.states
[ACPI_STATE_C1
].desc
,
305 ACPI_CX_DESC_LEN
, "ACPI HLT");
307 /* the C0 state only exists as a filler in our array */
308 pr
->power
.states
[ACPI_STATE_C0
].valid
= 1;
312 static int acpi_processor_get_power_info_cst(struct acpi_processor
*pr
)
318 struct acpi_buffer buffer
= { ACPI_ALLOCATE_BUFFER
, NULL
};
319 union acpi_object
*cst
;
326 status
= acpi_evaluate_object(pr
->handle
, "_CST", NULL
, &buffer
);
327 if (ACPI_FAILURE(status
)) {
328 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "No _CST, giving up\n"));
332 cst
= buffer
.pointer
;
334 /* There must be at least 2 elements */
335 if (!cst
|| (cst
->type
!= ACPI_TYPE_PACKAGE
) || cst
->package
.count
< 2) {
336 pr_err("not enough elements in _CST\n");
341 count
= cst
->package
.elements
[0].integer
.value
;
343 /* Validate number of power states. */
344 if (count
< 1 || count
!= cst
->package
.count
- 1) {
345 pr_err("count given by _CST is not valid\n");
350 /* Tell driver that at least _CST is supported. */
351 pr
->flags
.has_cst
= 1;
353 for (i
= 1; i
<= count
; i
++) {
354 union acpi_object
*element
;
355 union acpi_object
*obj
;
356 struct acpi_power_register
*reg
;
357 struct acpi_processor_cx cx
;
359 memset(&cx
, 0, sizeof(cx
));
361 element
= &(cst
->package
.elements
[i
]);
362 if (element
->type
!= ACPI_TYPE_PACKAGE
)
365 if (element
->package
.count
!= 4)
368 obj
= &(element
->package
.elements
[0]);
370 if (obj
->type
!= ACPI_TYPE_BUFFER
)
373 reg
= (struct acpi_power_register
*)obj
->buffer
.pointer
;
375 if (reg
->space_id
!= ACPI_ADR_SPACE_SYSTEM_IO
&&
376 (reg
->space_id
!= ACPI_ADR_SPACE_FIXED_HARDWARE
))
379 /* There should be an easy way to extract an integer... */
380 obj
= &(element
->package
.elements
[1]);
381 if (obj
->type
!= ACPI_TYPE_INTEGER
)
384 cx
.type
= obj
->integer
.value
;
386 * Some buggy BIOSes won't list C1 in _CST -
387 * Let acpi_processor_get_power_info_default() handle them later
389 if (i
== 1 && cx
.type
!= ACPI_STATE_C1
)
392 cx
.address
= reg
->address
;
393 cx
.index
= current_count
+ 1;
395 cx
.entry_method
= ACPI_CSTATE_SYSTEMIO
;
396 if (reg
->space_id
== ACPI_ADR_SPACE_FIXED_HARDWARE
) {
397 if (acpi_processor_ffh_cstate_probe
398 (pr
->id
, &cx
, reg
) == 0) {
399 cx
.entry_method
= ACPI_CSTATE_FFH
;
400 } else if (cx
.type
== ACPI_STATE_C1
) {
402 * C1 is a special case where FIXED_HARDWARE
403 * can be handled in non-MWAIT way as well.
404 * In that case, save this _CST entry info.
405 * Otherwise, ignore this info and continue.
407 cx
.entry_method
= ACPI_CSTATE_HALT
;
408 snprintf(cx
.desc
, ACPI_CX_DESC_LEN
, "ACPI HLT");
412 if (cx
.type
== ACPI_STATE_C1
&&
413 (boot_option_idle_override
== IDLE_NOMWAIT
)) {
415 * In most cases the C1 space_id obtained from
416 * _CST object is FIXED_HARDWARE access mode.
417 * But when the option of idle=halt is added,
418 * the entry_method type should be changed from
419 * CSTATE_FFH to CSTATE_HALT.
420 * When the option of idle=nomwait is added,
421 * the C1 entry_method type should be
424 cx
.entry_method
= ACPI_CSTATE_HALT
;
425 snprintf(cx
.desc
, ACPI_CX_DESC_LEN
, "ACPI HLT");
428 snprintf(cx
.desc
, ACPI_CX_DESC_LEN
, "ACPI IOPORT 0x%x",
432 if (cx
.type
== ACPI_STATE_C1
) {
436 obj
= &(element
->package
.elements
[2]);
437 if (obj
->type
!= ACPI_TYPE_INTEGER
)
440 cx
.latency
= obj
->integer
.value
;
442 obj
= &(element
->package
.elements
[3]);
443 if (obj
->type
!= ACPI_TYPE_INTEGER
)
447 memcpy(&(pr
->power
.states
[current_count
]), &cx
, sizeof(cx
));
450 * We support total ACPI_PROCESSOR_MAX_POWER - 1
451 * (From 1 through ACPI_PROCESSOR_MAX_POWER - 1)
453 if (current_count
>= (ACPI_PROCESSOR_MAX_POWER
- 1)) {
454 pr_warn("Limiting number of power states to max (%d)\n",
455 ACPI_PROCESSOR_MAX_POWER
);
456 pr_warn("Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n");
461 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Found %d power states\n",
464 /* Validate number of power states discovered */
465 if (current_count
< 2)
469 kfree(buffer
.pointer
);
474 static void acpi_processor_power_verify_c3(struct acpi_processor
*pr
,
475 struct acpi_processor_cx
*cx
)
477 static int bm_check_flag
= -1;
478 static int bm_control_flag
= -1;
485 * PIIX4 Erratum #18: We don't support C3 when Type-F (fast)
486 * DMA transfers are used by any ISA device to avoid livelock.
487 * Note that we could disable Type-F DMA (as recommended by
488 * the erratum), but this is known to disrupt certain ISA
489 * devices thus we take the conservative approach.
491 else if (errata
.piix4
.fdma
) {
492 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
493 "C3 not supported on PIIX4 with Type-F DMA\n"));
497 /* All the logic here assumes flags.bm_check is same across all CPUs */
498 if (bm_check_flag
== -1) {
499 /* Determine whether bm_check is needed based on CPU */
500 acpi_processor_power_init_bm_check(&(pr
->flags
), pr
->id
);
501 bm_check_flag
= pr
->flags
.bm_check
;
502 bm_control_flag
= pr
->flags
.bm_control
;
504 pr
->flags
.bm_check
= bm_check_flag
;
505 pr
->flags
.bm_control
= bm_control_flag
;
508 if (pr
->flags
.bm_check
) {
509 if (!pr
->flags
.bm_control
) {
510 if (pr
->flags
.has_cst
!= 1) {
511 /* bus mastering control is necessary */
512 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
513 "C3 support requires BM control\n"));
516 /* Here we enter C3 without bus mastering */
517 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
518 "C3 support without BM control\n"));
523 * WBINVD should be set in fadt, for C3 state to be
524 * supported on when bm_check is not required.
526 if (!(acpi_gbl_FADT
.flags
& ACPI_FADT_WBINVD
)) {
527 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
528 "Cache invalidation should work properly"
529 " for C3 to be enabled on SMP systems\n"));
535 * Otherwise we've met all of our C3 requirements.
536 * Normalize the C3 latency to expidite policy. Enable
537 * checking of bus mastering status (bm_check) so we can
538 * use this in our C3 policy
543 * On older chipsets, BM_RLD needs to be set
544 * in order for Bus Master activity to wake the
545 * system from C3. Newer chipsets handle DMA
546 * during C3 automatically and BM_RLD is a NOP.
547 * In either case, the proper way to
548 * handle BM_RLD is to set it and leave it set.
550 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD
, 1);
555 static int acpi_processor_power_verify(struct acpi_processor
*pr
)
558 unsigned int working
= 0;
560 pr
->power
.timer_broadcast_on_state
= INT_MAX
;
562 for (i
= 1; i
< ACPI_PROCESSOR_MAX_POWER
&& i
<= max_cstate
; i
++) {
563 struct acpi_processor_cx
*cx
= &pr
->power
.states
[i
];
577 acpi_processor_power_verify_c3(pr
, cx
);
583 lapic_timer_check_state(i
, pr
, cx
);
584 tsc_check_state(cx
->type
);
588 lapic_timer_propagate_broadcast(pr
);
593 static int acpi_processor_get_cstate_info(struct acpi_processor
*pr
)
599 /* NOTE: the idle thread may not be running while calling
602 /* Zero initialize all the C-states info. */
603 memset(pr
->power
.states
, 0, sizeof(pr
->power
.states
));
605 result
= acpi_processor_get_power_info_cst(pr
);
606 if (result
== -ENODEV
)
607 result
= acpi_processor_get_power_info_fadt(pr
);
612 acpi_processor_get_power_info_default(pr
);
614 pr
->power
.count
= acpi_processor_power_verify(pr
);
617 * if one state of type C2 or C3 is available, mark this
618 * CPU as being "idle manageable"
620 for (i
= 1; i
< ACPI_PROCESSOR_MAX_POWER
; i
++) {
621 if (pr
->power
.states
[i
].valid
) {
623 if (pr
->power
.states
[i
].type
>= ACPI_STATE_C2
)
632 * acpi_idle_bm_check - checks if bus master activity was detected
634 static int acpi_idle_bm_check(void)
638 if (bm_check_disable
)
641 acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_STATUS
, &bm_status
);
643 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_STATUS
, 1);
645 * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect
646 * the true state of bus mastering activity; forcing us to
647 * manually check the BMIDEA bit of each IDE channel.
649 else if (errata
.piix4
.bmisx
) {
650 if ((inb_p(errata
.piix4
.bmisx
+ 0x02) & 0x01)
651 || (inb_p(errata
.piix4
.bmisx
+ 0x0A) & 0x01))
658 * acpi_idle_do_entry - enter idle state using the appropriate method
661 * Caller disables interrupt before call and enables interrupt after return.
663 static void __cpuidle
acpi_idle_do_entry(struct acpi_processor_cx
*cx
)
665 if (cx
->entry_method
== ACPI_CSTATE_FFH
) {
666 /* Call into architectural FFH based C-state */
667 acpi_processor_ffh_cstate_enter(cx
);
668 } else if (cx
->entry_method
== ACPI_CSTATE_HALT
) {
671 /* IO port based C-state */
673 /* Dummy wait op - must do something useless after P_LVL2 read
674 because chipsets cannot guarantee that STPCLK# signal
675 gets asserted in time to freeze execution properly. */
676 inl(acpi_gbl_FADT
.xpm_timer_block
.address
);
681 * acpi_idle_play_dead - enters an ACPI state for long-term idle (i.e. off-lining)
682 * @dev: the target CPU
683 * @index: the index of suggested state
685 static int acpi_idle_play_dead(struct cpuidle_device
*dev
, int index
)
687 struct acpi_processor_cx
*cx
= per_cpu(acpi_cstate
[index
], dev
->cpu
);
689 ACPI_FLUSH_CPU_CACHE();
693 if (cx
->entry_method
== ACPI_CSTATE_HALT
)
695 else if (cx
->entry_method
== ACPI_CSTATE_SYSTEMIO
) {
697 /* See comment in acpi_idle_do_entry() */
698 inl(acpi_gbl_FADT
.xpm_timer_block
.address
);
707 static bool acpi_idle_fallback_to_c1(struct acpi_processor
*pr
)
709 return IS_ENABLED(CONFIG_HOTPLUG_CPU
) && !pr
->flags
.has_cst
&&
710 !(acpi_gbl_FADT
.flags
& ACPI_FADT_C2_MP_SUPPORTED
);
713 static int c3_cpu_count
;
714 static DEFINE_RAW_SPINLOCK(c3_lock
);
717 * acpi_idle_enter_bm - enters C3 with proper BM handling
718 * @pr: Target processor
719 * @cx: Target state context
720 * @timer_bc: Whether or not to change timer mode to broadcast
722 static void acpi_idle_enter_bm(struct acpi_processor
*pr
,
723 struct acpi_processor_cx
*cx
, bool timer_bc
)
725 acpi_unlazy_tlb(smp_processor_id());
728 * Must be done before busmaster disable as we might need to
732 lapic_timer_state_broadcast(pr
, cx
, 1);
736 * bm_check implies we need ARB_DIS
737 * bm_control implies whether we can do ARB_DIS
739 * That leaves a case where bm_check is set and bm_control is
740 * not set. In that case we cannot do much, we enter C3
741 * without doing anything.
743 if (pr
->flags
.bm_control
) {
744 raw_spin_lock(&c3_lock
);
746 /* Disable bus master arbitration when all CPUs are in C3 */
747 if (c3_cpu_count
== num_online_cpus())
748 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE
, 1);
749 raw_spin_unlock(&c3_lock
);
752 acpi_idle_do_entry(cx
);
754 /* Re-enable bus master arbitration */
755 if (pr
->flags
.bm_control
) {
756 raw_spin_lock(&c3_lock
);
757 acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE
, 0);
759 raw_spin_unlock(&c3_lock
);
763 lapic_timer_state_broadcast(pr
, cx
, 0);
766 static int acpi_idle_enter(struct cpuidle_device
*dev
,
767 struct cpuidle_driver
*drv
, int index
)
769 struct acpi_processor_cx
*cx
= per_cpu(acpi_cstate
[index
], dev
->cpu
);
770 struct acpi_processor
*pr
;
772 pr
= __this_cpu_read(processors
);
776 if (cx
->type
!= ACPI_STATE_C1
) {
777 if (acpi_idle_fallback_to_c1(pr
) && num_online_cpus() > 1) {
778 index
= ACPI_IDLE_STATE_START
;
779 cx
= per_cpu(acpi_cstate
[index
], dev
->cpu
);
780 } else if (cx
->type
== ACPI_STATE_C3
&& pr
->flags
.bm_check
) {
781 if (cx
->bm_sts_skip
|| !acpi_idle_bm_check()) {
782 acpi_idle_enter_bm(pr
, cx
, true);
784 } else if (drv
->safe_state_index
>= 0) {
785 index
= drv
->safe_state_index
;
786 cx
= per_cpu(acpi_cstate
[index
], dev
->cpu
);
794 lapic_timer_state_broadcast(pr
, cx
, 1);
796 if (cx
->type
== ACPI_STATE_C3
)
797 ACPI_FLUSH_CPU_CACHE();
799 acpi_idle_do_entry(cx
);
801 lapic_timer_state_broadcast(pr
, cx
, 0);
806 static void acpi_idle_enter_s2idle(struct cpuidle_device
*dev
,
807 struct cpuidle_driver
*drv
, int index
)
809 struct acpi_processor_cx
*cx
= per_cpu(acpi_cstate
[index
], dev
->cpu
);
811 if (cx
->type
== ACPI_STATE_C3
) {
812 struct acpi_processor
*pr
= __this_cpu_read(processors
);
817 if (pr
->flags
.bm_check
) {
818 acpi_idle_enter_bm(pr
, cx
, false);
821 ACPI_FLUSH_CPU_CACHE();
824 acpi_idle_do_entry(cx
);
827 static int acpi_processor_setup_cpuidle_cx(struct acpi_processor
*pr
,
828 struct cpuidle_device
*dev
)
830 int i
, count
= ACPI_IDLE_STATE_START
;
831 struct acpi_processor_cx
*cx
;
836 for (i
= 1; i
< ACPI_PROCESSOR_MAX_POWER
&& i
<= max_cstate
; i
++) {
837 cx
= &pr
->power
.states
[i
];
842 per_cpu(acpi_cstate
[count
], dev
->cpu
) = cx
;
845 if (count
== CPUIDLE_STATE_MAX
)
855 static int acpi_processor_setup_cstates(struct acpi_processor
*pr
)
858 struct acpi_processor_cx
*cx
;
859 struct cpuidle_state
*state
;
860 struct cpuidle_driver
*drv
= &acpi_idle_driver
;
865 if (IS_ENABLED(CONFIG_ARCH_HAS_CPU_RELAX
)) {
866 cpuidle_poll_state_init(drv
);
872 for (i
= 1; i
< ACPI_PROCESSOR_MAX_POWER
&& i
<= max_cstate
; i
++) {
873 cx
= &pr
->power
.states
[i
];
878 state
= &drv
->states
[count
];
879 snprintf(state
->name
, CPUIDLE_NAME_LEN
, "C%d", i
);
880 strlcpy(state
->desc
, cx
->desc
, CPUIDLE_DESC_LEN
);
881 state
->exit_latency
= cx
->latency
;
882 state
->target_residency
= cx
->latency
* latency_factor
;
883 state
->enter
= acpi_idle_enter
;
886 if (cx
->type
== ACPI_STATE_C1
|| cx
->type
== ACPI_STATE_C2
) {
887 state
->enter_dead
= acpi_idle_play_dead
;
888 drv
->safe_state_index
= count
;
891 * Halt-induced C1 is not good for ->enter_s2idle, because it
892 * re-enables interrupts on exit. Moreover, C1 is generally not
893 * particularly interesting from the suspend-to-idle angle, so
894 * avoid C1 and the situations in which we may need to fall back
897 if (cx
->type
!= ACPI_STATE_C1
&& !acpi_idle_fallback_to_c1(pr
))
898 state
->enter_s2idle
= acpi_idle_enter_s2idle
;
901 if (count
== CPUIDLE_STATE_MAX
)
905 drv
->state_count
= count
;
913 static inline void acpi_processor_cstate_first_run_checks(void)
916 static int first_run
;
920 dmi_check_system(processor_power_dmi_table
);
921 max_cstate
= acpi_processor_cstate_check(max_cstate
);
922 if (max_cstate
< ACPI_C_STATES_MAX
)
923 pr_notice("ACPI: processor limited to max C-state %d\n",
927 if (acpi_gbl_FADT
.cst_control
&& !nocst
) {
928 status
= acpi_os_write_port(acpi_gbl_FADT
.smi_command
,
929 acpi_gbl_FADT
.cst_control
, 8);
930 if (ACPI_FAILURE(status
))
931 ACPI_EXCEPTION((AE_INFO
, status
,
932 "Notifying BIOS of _CST ability failed"));
937 static inline int disabled_by_idle_boot_param(void) { return 0; }
938 static inline void acpi_processor_cstate_first_run_checks(void) { }
939 static int acpi_processor_get_cstate_info(struct acpi_processor
*pr
)
944 static int acpi_processor_setup_cpuidle_cx(struct acpi_processor
*pr
,
945 struct cpuidle_device
*dev
)
950 static int acpi_processor_setup_cstates(struct acpi_processor
*pr
)
955 #endif /* CONFIG_ACPI_PROCESSOR_CSTATE */
957 struct acpi_lpi_states_array
{
959 unsigned int composite_states_size
;
960 struct acpi_lpi_state
*entries
;
961 struct acpi_lpi_state
*composite_states
[ACPI_PROCESSOR_MAX_POWER
];
964 static int obj_get_integer(union acpi_object
*obj
, u32
*value
)
966 if (obj
->type
!= ACPI_TYPE_INTEGER
)
969 *value
= obj
->integer
.value
;
973 static int acpi_processor_evaluate_lpi(acpi_handle handle
,
974 struct acpi_lpi_states_array
*info
)
978 int pkg_count
, state_idx
= 1, loop
;
979 struct acpi_buffer buffer
= { ACPI_ALLOCATE_BUFFER
, NULL
};
980 union acpi_object
*lpi_data
;
981 struct acpi_lpi_state
*lpi_state
;
983 status
= acpi_evaluate_object(handle
, "_LPI", NULL
, &buffer
);
984 if (ACPI_FAILURE(status
)) {
985 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "No _LPI, giving up\n"));
989 lpi_data
= buffer
.pointer
;
991 /* There must be at least 4 elements = 3 elements + 1 package */
992 if (!lpi_data
|| lpi_data
->type
!= ACPI_TYPE_PACKAGE
||
993 lpi_data
->package
.count
< 4) {
994 pr_debug("not enough elements in _LPI\n");
999 pkg_count
= lpi_data
->package
.elements
[2].integer
.value
;
1001 /* Validate number of power states. */
1002 if (pkg_count
< 1 || pkg_count
!= lpi_data
->package
.count
- 3) {
1003 pr_debug("count given by _LPI is not valid\n");
1008 lpi_state
= kcalloc(pkg_count
, sizeof(*lpi_state
), GFP_KERNEL
);
1014 info
->size
= pkg_count
;
1015 info
->entries
= lpi_state
;
1017 /* LPI States start at index 3 */
1018 for (loop
= 3; state_idx
<= pkg_count
; loop
++, state_idx
++, lpi_state
++) {
1019 union acpi_object
*element
, *pkg_elem
, *obj
;
1021 element
= &lpi_data
->package
.elements
[loop
];
1022 if (element
->type
!= ACPI_TYPE_PACKAGE
|| element
->package
.count
< 7)
1025 pkg_elem
= element
->package
.elements
;
1028 if (obj
->type
== ACPI_TYPE_BUFFER
) {
1029 struct acpi_power_register
*reg
;
1031 reg
= (struct acpi_power_register
*)obj
->buffer
.pointer
;
1032 if (reg
->space_id
!= ACPI_ADR_SPACE_SYSTEM_IO
&&
1033 reg
->space_id
!= ACPI_ADR_SPACE_FIXED_HARDWARE
)
1036 lpi_state
->address
= reg
->address
;
1037 lpi_state
->entry_method
=
1038 reg
->space_id
== ACPI_ADR_SPACE_FIXED_HARDWARE
?
1039 ACPI_CSTATE_FFH
: ACPI_CSTATE_SYSTEMIO
;
1040 } else if (obj
->type
== ACPI_TYPE_INTEGER
) {
1041 lpi_state
->entry_method
= ACPI_CSTATE_INTEGER
;
1042 lpi_state
->address
= obj
->integer
.value
;
1047 /* elements[7,8] skipped for now i.e. Residency/Usage counter*/
1050 if (obj
->type
== ACPI_TYPE_STRING
)
1051 strlcpy(lpi_state
->desc
, obj
->string
.pointer
,
1054 lpi_state
->index
= state_idx
;
1055 if (obj_get_integer(pkg_elem
+ 0, &lpi_state
->min_residency
)) {
1056 pr_debug("No min. residency found, assuming 10 us\n");
1057 lpi_state
->min_residency
= 10;
1060 if (obj_get_integer(pkg_elem
+ 1, &lpi_state
->wake_latency
)) {
1061 pr_debug("No wakeup residency found, assuming 10 us\n");
1062 lpi_state
->wake_latency
= 10;
1065 if (obj_get_integer(pkg_elem
+ 2, &lpi_state
->flags
))
1066 lpi_state
->flags
= 0;
1068 if (obj_get_integer(pkg_elem
+ 3, &lpi_state
->arch_flags
))
1069 lpi_state
->arch_flags
= 0;
1071 if (obj_get_integer(pkg_elem
+ 4, &lpi_state
->res_cnt_freq
))
1072 lpi_state
->res_cnt_freq
= 1;
1074 if (obj_get_integer(pkg_elem
+ 5, &lpi_state
->enable_parent_state
))
1075 lpi_state
->enable_parent_state
= 0;
1078 acpi_handle_debug(handle
, "Found %d power states\n", state_idx
);
1080 kfree(buffer
.pointer
);
1085 * flat_state_cnt - the number of composite LPI states after the process of flattening
1087 static int flat_state_cnt
;
1090 * combine_lpi_states - combine local and parent LPI states to form a composite LPI state
1092 * @local: local LPI state
1093 * @parent: parent LPI state
1094 * @result: composite LPI state
1096 static bool combine_lpi_states(struct acpi_lpi_state
*local
,
1097 struct acpi_lpi_state
*parent
,
1098 struct acpi_lpi_state
*result
)
1100 if (parent
->entry_method
== ACPI_CSTATE_INTEGER
) {
1101 if (!parent
->address
) /* 0 means autopromotable */
1103 result
->address
= local
->address
+ parent
->address
;
1105 result
->address
= parent
->address
;
1108 result
->min_residency
= max(local
->min_residency
, parent
->min_residency
);
1109 result
->wake_latency
= local
->wake_latency
+ parent
->wake_latency
;
1110 result
->enable_parent_state
= parent
->enable_parent_state
;
1111 result
->entry_method
= local
->entry_method
;
1113 result
->flags
= parent
->flags
;
1114 result
->arch_flags
= parent
->arch_flags
;
1115 result
->index
= parent
->index
;
1117 strlcpy(result
->desc
, local
->desc
, ACPI_CX_DESC_LEN
);
1118 strlcat(result
->desc
, "+", ACPI_CX_DESC_LEN
);
1119 strlcat(result
->desc
, parent
->desc
, ACPI_CX_DESC_LEN
);
1123 #define ACPI_LPI_STATE_FLAGS_ENABLED BIT(0)
1125 static void stash_composite_state(struct acpi_lpi_states_array
*curr_level
,
1126 struct acpi_lpi_state
*t
)
1128 curr_level
->composite_states
[curr_level
->composite_states_size
++] = t
;
1131 static int flatten_lpi_states(struct acpi_processor
*pr
,
1132 struct acpi_lpi_states_array
*curr_level
,
1133 struct acpi_lpi_states_array
*prev_level
)
1135 int i
, j
, state_count
= curr_level
->size
;
1136 struct acpi_lpi_state
*p
, *t
= curr_level
->entries
;
1138 curr_level
->composite_states_size
= 0;
1139 for (j
= 0; j
< state_count
; j
++, t
++) {
1140 struct acpi_lpi_state
*flpi
;
1142 if (!(t
->flags
& ACPI_LPI_STATE_FLAGS_ENABLED
))
1145 if (flat_state_cnt
>= ACPI_PROCESSOR_MAX_POWER
) {
1146 pr_warn("Limiting number of LPI states to max (%d)\n",
1147 ACPI_PROCESSOR_MAX_POWER
);
1148 pr_warn("Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n");
1152 flpi
= &pr
->power
.lpi_states
[flat_state_cnt
];
1154 if (!prev_level
) { /* leaf/processor node */
1155 memcpy(flpi
, t
, sizeof(*t
));
1156 stash_composite_state(curr_level
, flpi
);
1161 for (i
= 0; i
< prev_level
->composite_states_size
; i
++) {
1162 p
= prev_level
->composite_states
[i
];
1163 if (t
->index
<= p
->enable_parent_state
&&
1164 combine_lpi_states(p
, t
, flpi
)) {
1165 stash_composite_state(curr_level
, flpi
);
1172 kfree(curr_level
->entries
);
1176 static int acpi_processor_get_lpi_info(struct acpi_processor
*pr
)
1180 acpi_handle handle
= pr
->handle
, pr_ahandle
;
1181 struct acpi_device
*d
= NULL
;
1182 struct acpi_lpi_states_array info
[2], *tmp
, *prev
, *curr
;
1184 if (!osc_pc_lpi_support_confirmed
)
1187 if (!acpi_has_method(handle
, "_LPI"))
1193 handle
= pr
->handle
;
1194 ret
= acpi_processor_evaluate_lpi(handle
, prev
);
1197 flatten_lpi_states(pr
, prev
, NULL
);
1199 status
= acpi_get_parent(handle
, &pr_ahandle
);
1200 while (ACPI_SUCCESS(status
)) {
1201 acpi_bus_get_device(pr_ahandle
, &d
);
1202 handle
= pr_ahandle
;
1204 if (strcmp(acpi_device_hid(d
), ACPI_PROCESSOR_CONTAINER_HID
))
1207 /* can be optional ? */
1208 if (!acpi_has_method(handle
, "_LPI"))
1211 ret
= acpi_processor_evaluate_lpi(handle
, curr
);
1215 /* flatten all the LPI states in this level of hierarchy */
1216 flatten_lpi_states(pr
, curr
, prev
);
1218 tmp
= prev
, prev
= curr
, curr
= tmp
;
1220 status
= acpi_get_parent(handle
, &pr_ahandle
);
1223 pr
->power
.count
= flat_state_cnt
;
1224 /* reset the index after flattening */
1225 for (i
= 0; i
< pr
->power
.count
; i
++)
1226 pr
->power
.lpi_states
[i
].index
= i
;
1228 /* Tell driver that _LPI is supported. */
1229 pr
->flags
.has_lpi
= 1;
1230 pr
->flags
.power
= 1;
1235 int __weak
acpi_processor_ffh_lpi_probe(unsigned int cpu
)
1240 int __weak
acpi_processor_ffh_lpi_enter(struct acpi_lpi_state
*lpi
)
1246 * acpi_idle_lpi_enter - enters an ACPI any LPI state
1247 * @dev: the target CPU
1248 * @drv: cpuidle driver containing cpuidle state info
1249 * @index: index of target state
1251 * Return: 0 for success or negative value for error
1253 static int acpi_idle_lpi_enter(struct cpuidle_device
*dev
,
1254 struct cpuidle_driver
*drv
, int index
)
1256 struct acpi_processor
*pr
;
1257 struct acpi_lpi_state
*lpi
;
1259 pr
= __this_cpu_read(processors
);
1264 lpi
= &pr
->power
.lpi_states
[index
];
1265 if (lpi
->entry_method
== ACPI_CSTATE_FFH
)
1266 return acpi_processor_ffh_lpi_enter(lpi
);
1271 static int acpi_processor_setup_lpi_states(struct acpi_processor
*pr
)
1274 struct acpi_lpi_state
*lpi
;
1275 struct cpuidle_state
*state
;
1276 struct cpuidle_driver
*drv
= &acpi_idle_driver
;
1278 if (!pr
->flags
.has_lpi
)
1281 for (i
= 0; i
< pr
->power
.count
&& i
< CPUIDLE_STATE_MAX
; i
++) {
1282 lpi
= &pr
->power
.lpi_states
[i
];
1284 state
= &drv
->states
[i
];
1285 snprintf(state
->name
, CPUIDLE_NAME_LEN
, "LPI-%d", i
);
1286 strlcpy(state
->desc
, lpi
->desc
, CPUIDLE_DESC_LEN
);
1287 state
->exit_latency
= lpi
->wake_latency
;
1288 state
->target_residency
= lpi
->min_residency
;
1289 if (lpi
->arch_flags
)
1290 state
->flags
|= CPUIDLE_FLAG_TIMER_STOP
;
1291 state
->enter
= acpi_idle_lpi_enter
;
1292 drv
->safe_state_index
= i
;
1295 drv
->state_count
= i
;
1301 * acpi_processor_setup_cpuidle_states- prepares and configures cpuidle
1302 * global state data i.e. idle routines
1304 * @pr: the ACPI processor
1306 static int acpi_processor_setup_cpuidle_states(struct acpi_processor
*pr
)
1309 struct cpuidle_driver
*drv
= &acpi_idle_driver
;
1311 if (!pr
->flags
.power_setup_done
|| !pr
->flags
.power
)
1314 drv
->safe_state_index
= -1;
1315 for (i
= ACPI_IDLE_STATE_START
; i
< CPUIDLE_STATE_MAX
; i
++) {
1316 drv
->states
[i
].name
[0] = '\0';
1317 drv
->states
[i
].desc
[0] = '\0';
1320 if (pr
->flags
.has_lpi
)
1321 return acpi_processor_setup_lpi_states(pr
);
1323 return acpi_processor_setup_cstates(pr
);
1327 * acpi_processor_setup_cpuidle_dev - prepares and configures CPUIDLE
1328 * device i.e. per-cpu data
1330 * @pr: the ACPI processor
1331 * @dev : the cpuidle device
1333 static int acpi_processor_setup_cpuidle_dev(struct acpi_processor
*pr
,
1334 struct cpuidle_device
*dev
)
1336 if (!pr
->flags
.power_setup_done
|| !pr
->flags
.power
|| !dev
)
1340 if (pr
->flags
.has_lpi
)
1341 return acpi_processor_ffh_lpi_probe(pr
->id
);
1343 return acpi_processor_setup_cpuidle_cx(pr
, dev
);
1346 static int acpi_processor_get_power_info(struct acpi_processor
*pr
)
1350 ret
= acpi_processor_get_lpi_info(pr
);
1352 ret
= acpi_processor_get_cstate_info(pr
);
1357 int acpi_processor_hotplug(struct acpi_processor
*pr
)
1360 struct cpuidle_device
*dev
;
1362 if (disabled_by_idle_boot_param())
1365 if (!pr
->flags
.power_setup_done
)
1368 dev
= per_cpu(acpi_cpuidle_device
, pr
->id
);
1369 cpuidle_pause_and_lock();
1370 cpuidle_disable_device(dev
);
1371 ret
= acpi_processor_get_power_info(pr
);
1372 if (!ret
&& pr
->flags
.power
) {
1373 acpi_processor_setup_cpuidle_dev(pr
, dev
);
1374 ret
= cpuidle_enable_device(dev
);
1376 cpuidle_resume_and_unlock();
1381 int acpi_processor_power_state_has_changed(struct acpi_processor
*pr
)
1384 struct acpi_processor
*_pr
;
1385 struct cpuidle_device
*dev
;
1387 if (disabled_by_idle_boot_param())
1390 if (!pr
->flags
.power_setup_done
)
1394 * FIXME: Design the ACPI notification to make it once per
1395 * system instead of once per-cpu. This condition is a hack
1396 * to make the code that updates C-States be called once.
1399 if (pr
->id
== 0 && cpuidle_get_driver() == &acpi_idle_driver
) {
1401 /* Protect against cpu-hotplug */
1403 cpuidle_pause_and_lock();
1405 /* Disable all cpuidle devices */
1406 for_each_online_cpu(cpu
) {
1407 _pr
= per_cpu(processors
, cpu
);
1408 if (!_pr
|| !_pr
->flags
.power_setup_done
)
1410 dev
= per_cpu(acpi_cpuidle_device
, cpu
);
1411 cpuidle_disable_device(dev
);
1414 /* Populate Updated C-state information */
1415 acpi_processor_get_power_info(pr
);
1416 acpi_processor_setup_cpuidle_states(pr
);
1418 /* Enable all cpuidle devices */
1419 for_each_online_cpu(cpu
) {
1420 _pr
= per_cpu(processors
, cpu
);
1421 if (!_pr
|| !_pr
->flags
.power_setup_done
)
1423 acpi_processor_get_power_info(_pr
);
1424 if (_pr
->flags
.power
) {
1425 dev
= per_cpu(acpi_cpuidle_device
, cpu
);
1426 acpi_processor_setup_cpuidle_dev(_pr
, dev
);
1427 cpuidle_enable_device(dev
);
1430 cpuidle_resume_and_unlock();
1437 static int acpi_processor_registered
;
1439 int acpi_processor_power_init(struct acpi_processor
*pr
)
1442 struct cpuidle_device
*dev
;
1444 if (disabled_by_idle_boot_param())
1447 acpi_processor_cstate_first_run_checks();
1449 if (!acpi_processor_get_power_info(pr
))
1450 pr
->flags
.power_setup_done
= 1;
1453 * Install the idle handler if processor power management is supported.
1454 * Note that we use previously set idle handler will be used on
1455 * platforms that only support C1.
1457 if (pr
->flags
.power
) {
1458 /* Register acpi_idle_driver if not already registered */
1459 if (!acpi_processor_registered
) {
1460 acpi_processor_setup_cpuidle_states(pr
);
1461 retval
= cpuidle_register_driver(&acpi_idle_driver
);
1464 pr_debug("%s registered with cpuidle\n",
1465 acpi_idle_driver
.name
);
1468 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
1471 per_cpu(acpi_cpuidle_device
, pr
->id
) = dev
;
1473 acpi_processor_setup_cpuidle_dev(pr
, dev
);
1475 /* Register per-cpu cpuidle_device. Cpuidle driver
1476 * must already be registered before registering device
1478 retval
= cpuidle_register_device(dev
);
1480 if (acpi_processor_registered
== 0)
1481 cpuidle_unregister_driver(&acpi_idle_driver
);
1484 acpi_processor_registered
++;
1489 int acpi_processor_power_exit(struct acpi_processor
*pr
)
1491 struct cpuidle_device
*dev
= per_cpu(acpi_cpuidle_device
, pr
->id
);
1493 if (disabled_by_idle_boot_param())
1496 if (pr
->flags
.power
) {
1497 cpuidle_unregister_device(dev
);
1498 acpi_processor_registered
--;
1499 if (acpi_processor_registered
== 0)
1500 cpuidle_unregister_driver(&acpi_idle_driver
);
1503 pr
->flags
.power_setup_done
= 0;