2 * sleep.c - ACPI sleep support.
4 * Copyright (c) 2005 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
5 * Copyright (c) 2004 David Shaohua Li <shaohua.li@intel.com>
6 * Copyright (c) 2000-2003 Patrick Mochel
7 * Copyright (c) 2003 Open Source Development Lab
9 * This file is released under the GPLv2.
13 #include <linux/delay.h>
14 #include <linux/irq.h>
15 #include <linux/dmi.h>
16 #include <linux/device.h>
17 #include <linux/suspend.h>
18 #include <linux/reboot.h>
22 #include <acpi/acpi_bus.h>
23 #include <acpi/acpi_drivers.h>
28 u8 sleep_states
[ACPI_S_STATE_COUNT
];
30 static void acpi_sleep_tts_switch(u32 acpi_state
)
32 union acpi_object in_arg
= { ACPI_TYPE_INTEGER
};
33 struct acpi_object_list arg_list
= { 1, &in_arg
};
34 acpi_status status
= AE_OK
;
36 in_arg
.integer
.value
= acpi_state
;
37 status
= acpi_evaluate_object(NULL
, "\\_TTS", &arg_list
, NULL
);
38 if (ACPI_FAILURE(status
) && status
!= AE_NOT_FOUND
) {
40 * OS can't evaluate the _TTS object correctly. Some warning
41 * message will be printed. But it won't break anything.
43 printk(KERN_NOTICE
"Failure in evaluating _TTS object\n");
47 static int tts_notify_reboot(struct notifier_block
*this,
48 unsigned long code
, void *x
)
50 acpi_sleep_tts_switch(ACPI_STATE_S5
);
54 static struct notifier_block tts_notifier
= {
55 .notifier_call
= tts_notify_reboot
,
60 static int acpi_sleep_prepare(u32 acpi_state
)
62 #ifdef CONFIG_ACPI_SLEEP
63 /* do we have a wakeup address for S2 and S3? */
64 if (acpi_state
== ACPI_STATE_S3
) {
65 if (!acpi_wakeup_address
) {
68 acpi_set_firmware_waking_vector(
69 (acpi_physical_address
)acpi_wakeup_address
);
72 ACPI_FLUSH_CPU_CACHE();
73 acpi_enable_wakeup_device_prep(acpi_state
);
75 printk(KERN_INFO PREFIX
"Preparing to enter system sleep state S%d\n",
77 acpi_enter_sleep_state_prep(acpi_state
);
81 #ifdef CONFIG_ACPI_SLEEP
82 static u32 acpi_target_sleep_state
= ACPI_STATE_S0
;
84 * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
85 * user to request that behavior by using the 'acpi_old_suspend_ordering'
86 * kernel command line option that causes the following variable to be set.
88 static bool old_suspend_ordering
;
90 void __init
acpi_old_suspend_ordering(void)
92 old_suspend_ordering
= true;
96 * acpi_pm_disable_gpes - Disable the GPEs.
98 static int acpi_pm_disable_gpes(void)
100 acpi_disable_all_gpes();
105 * __acpi_pm_prepare - Prepare the platform to enter the target state.
107 * If necessary, set the firmware waking vector and do arch-specific
108 * nastiness to get the wakeup code to the waking vector.
110 static int __acpi_pm_prepare(void)
112 int error
= acpi_sleep_prepare(acpi_target_sleep_state
);
115 acpi_target_sleep_state
= ACPI_STATE_S0
;
120 * acpi_pm_prepare - Prepare the platform to enter the target sleep
121 * state and disable the GPEs.
123 static int acpi_pm_prepare(void)
125 int error
= __acpi_pm_prepare();
128 acpi_disable_all_gpes();
133 * acpi_pm_finish - Instruct the platform to leave a sleep state.
135 * This is called after we wake back up (or if entering the sleep state
138 static void acpi_pm_finish(void)
140 u32 acpi_state
= acpi_target_sleep_state
;
142 if (acpi_state
== ACPI_STATE_S0
)
145 printk(KERN_INFO PREFIX
"Waking up from system sleep state S%d\n",
147 acpi_disable_wakeup_device(acpi_state
);
148 acpi_leave_sleep_state(acpi_state
);
150 /* reset firmware waking vector */
151 acpi_set_firmware_waking_vector((acpi_physical_address
) 0);
153 acpi_target_sleep_state
= ACPI_STATE_S0
;
157 * acpi_pm_end - Finish up suspend sequence.
159 static void acpi_pm_end(void)
162 * This is necessary in case acpi_pm_finish() is not called during a
163 * failing transition to a sleep state.
165 acpi_target_sleep_state
= ACPI_STATE_S0
;
166 acpi_sleep_tts_switch(acpi_target_sleep_state
);
168 #else /* !CONFIG_ACPI_SLEEP */
169 #define acpi_target_sleep_state ACPI_STATE_S0
170 #endif /* CONFIG_ACPI_SLEEP */
172 #ifdef CONFIG_SUSPEND
174 * According to the ACPI specification the BIOS should make sure that ACPI is
175 * enabled and SCI_EN bit is set on wake-up from S1 - S3 sleep states. Still,
176 * some BIOSes don't do that and therefore we use acpi_enable() to enable ACPI
177 * on such systems during resume. Unfortunately that doesn't help in
178 * particularly pathological cases in which SCI_EN has to be set directly on
179 * resume, although the specification states very clearly that this flag is
180 * owned by the hardware. The set_sci_en_on_resume variable will be set in such
183 static bool set_sci_en_on_resume
;
185 extern void do_suspend_lowlevel(void);
187 static u32 acpi_suspend_states
[] = {
188 [PM_SUSPEND_ON
] = ACPI_STATE_S0
,
189 [PM_SUSPEND_STANDBY
] = ACPI_STATE_S1
,
190 [PM_SUSPEND_MEM
] = ACPI_STATE_S3
,
191 [PM_SUSPEND_MAX
] = ACPI_STATE_S5
195 * acpi_suspend_begin - Set the target system sleep state to the state
196 * associated with given @pm_state, if supported.
198 static int acpi_suspend_begin(suspend_state_t pm_state
)
200 u32 acpi_state
= acpi_suspend_states
[pm_state
];
203 if (sleep_states
[acpi_state
]) {
204 acpi_target_sleep_state
= acpi_state
;
205 acpi_sleep_tts_switch(acpi_target_sleep_state
);
207 printk(KERN_ERR
"ACPI does not support this state: %d\n",
215 * acpi_suspend_enter - Actually enter a sleep state.
218 * Flush caches and go to sleep. For STR we have to call arch-specific
219 * assembly, which in turn call acpi_enter_sleep_state().
220 * It's unfortunate, but it works. Please fix if you're feeling frisky.
222 static int acpi_suspend_enter(suspend_state_t pm_state
)
224 acpi_status status
= AE_OK
;
225 unsigned long flags
= 0;
226 u32 acpi_state
= acpi_target_sleep_state
;
228 ACPI_FLUSH_CPU_CACHE();
230 /* Do arch specific saving of state. */
231 if (acpi_state
== ACPI_STATE_S3
) {
232 int error
= acpi_save_state_mem();
238 local_irq_save(flags
);
239 acpi_enable_wakeup_device(acpi_state
);
240 switch (acpi_state
) {
243 status
= acpi_enter_sleep_state(acpi_state
);
247 do_suspend_lowlevel();
251 /* If ACPI is not enabled by the BIOS, we need to enable it here. */
252 if (set_sci_en_on_resume
)
253 acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE
, 1);
257 /* Reprogram control registers and execute _BFS */
258 acpi_leave_sleep_state_prep(acpi_state
);
260 /* ACPI 3.0 specs (P62) says that it's the responsibility
261 * of the OSPM to clear the status bit [ implying that the
262 * POWER_BUTTON event should not reach userspace ]
264 if (ACPI_SUCCESS(status
) && (acpi_state
== ACPI_STATE_S3
))
265 acpi_clear_event(ACPI_EVENT_POWER_BUTTON
);
268 * Disable and clear GPE status before interrupt is enabled. Some GPEs
269 * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
270 * acpi_leave_sleep_state will reenable specific GPEs later
272 acpi_disable_all_gpes();
274 local_irq_restore(flags
);
275 printk(KERN_DEBUG
"Back to C!\n");
277 /* restore processor state */
278 if (acpi_state
== ACPI_STATE_S3
)
279 acpi_restore_state_mem();
281 return ACPI_SUCCESS(status
) ? 0 : -EFAULT
;
284 static int acpi_suspend_state_valid(suspend_state_t pm_state
)
290 case PM_SUSPEND_STANDBY
:
292 acpi_state
= acpi_suspend_states
[pm_state
];
294 return sleep_states
[acpi_state
];
300 static struct platform_suspend_ops acpi_suspend_ops
= {
301 .valid
= acpi_suspend_state_valid
,
302 .begin
= acpi_suspend_begin
,
303 .prepare_late
= acpi_pm_prepare
,
304 .enter
= acpi_suspend_enter
,
305 .wake
= acpi_pm_finish
,
310 * acpi_suspend_begin_old - Set the target system sleep state to the
311 * state associated with given @pm_state, if supported, and
312 * execute the _PTS control method. This function is used if the
313 * pre-ACPI 2.0 suspend ordering has been requested.
315 static int acpi_suspend_begin_old(suspend_state_t pm_state
)
317 int error
= acpi_suspend_begin(pm_state
);
320 error
= __acpi_pm_prepare();
325 * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
328 static struct platform_suspend_ops acpi_suspend_ops_old
= {
329 .valid
= acpi_suspend_state_valid
,
330 .begin
= acpi_suspend_begin_old
,
331 .prepare_late
= acpi_pm_disable_gpes
,
332 .enter
= acpi_suspend_enter
,
333 .wake
= acpi_pm_finish
,
335 .recover
= acpi_pm_finish
,
338 static int __init
init_old_suspend_ordering(const struct dmi_system_id
*d
)
340 old_suspend_ordering
= true;
344 static int __init
init_set_sci_en_on_resume(const struct dmi_system_id
*d
)
346 set_sci_en_on_resume
= true;
350 static struct dmi_system_id __initdata acpisleep_dmi_table
[] = {
352 .callback
= init_old_suspend_ordering
,
353 .ident
= "Abit KN9 (nForce4 variant)",
355 DMI_MATCH(DMI_BOARD_VENDOR
, "http://www.abit.com.tw/"),
356 DMI_MATCH(DMI_BOARD_NAME
, "KN9 Series(NF-CK804)"),
360 .callback
= init_old_suspend_ordering
,
361 .ident
= "HP xw4600 Workstation",
363 DMI_MATCH(DMI_SYS_VENDOR
, "Hewlett-Packard"),
364 DMI_MATCH(DMI_PRODUCT_NAME
, "HP xw4600 Workstation"),
368 .callback
= init_set_sci_en_on_resume
,
369 .ident
= "Apple MacBook 1,1",
371 DMI_MATCH(DMI_SYS_VENDOR
, "Apple Computer, Inc."),
372 DMI_MATCH(DMI_PRODUCT_NAME
, "MacBook1,1"),
376 .callback
= init_set_sci_en_on_resume
,
377 .ident
= "Apple MacMini 1,1",
379 DMI_MATCH(DMI_SYS_VENDOR
, "Apple Computer, Inc."),
380 DMI_MATCH(DMI_PRODUCT_NAME
, "Macmini1,1"),
384 .callback
= init_old_suspend_ordering
,
385 .ident
= "Asus Pundit P1-AH2 (M2N8L motherboard)",
387 DMI_MATCH(DMI_BOARD_VENDOR
, "ASUSTek Computer INC."),
388 DMI_MATCH(DMI_BOARD_NAME
, "M2N8L"),
392 .callback
= init_set_sci_en_on_resume
,
393 .ident
= "Toshiba Satellite L300",
395 DMI_MATCH(DMI_SYS_VENDOR
, "TOSHIBA"),
396 DMI_MATCH(DMI_PRODUCT_NAME
, "Satellite L300"),
400 .callback
= init_old_suspend_ordering
,
401 .ident
= "Panasonic CF51-2L",
403 DMI_MATCH(DMI_BOARD_VENDOR
,
404 "Matsushita Electric Industrial Co.,Ltd."),
405 DMI_MATCH(DMI_BOARD_NAME
, "CF51-2L"),
410 #endif /* CONFIG_SUSPEND */
412 #ifdef CONFIG_HIBERNATION
414 * The ACPI specification wants us to save NVS memory regions during hibernation
415 * and to restore them during the subsequent resume. However, it is not certain
416 * if this mechanism is going to work on all machines, so we allow the user to
417 * disable this mechanism using the 'acpi_sleep=s4_nonvs' kernel command line
420 static bool s4_no_nvs
;
422 void __init
acpi_s4_no_nvs(void)
427 static unsigned long s4_hardware_signature
;
428 static struct acpi_table_facs
*facs
;
429 static bool nosigcheck
;
431 void __init
acpi_no_s4_hw_signature(void)
436 static int acpi_hibernation_begin(void)
440 error
= s4_no_nvs
? 0 : hibernate_nvs_alloc();
442 acpi_target_sleep_state
= ACPI_STATE_S4
;
443 acpi_sleep_tts_switch(acpi_target_sleep_state
);
449 static int acpi_hibernation_pre_snapshot(void)
451 int error
= acpi_pm_prepare();
454 hibernate_nvs_save();
459 static int acpi_hibernation_enter(void)
461 acpi_status status
= AE_OK
;
462 unsigned long flags
= 0;
464 ACPI_FLUSH_CPU_CACHE();
466 local_irq_save(flags
);
467 acpi_enable_wakeup_device(ACPI_STATE_S4
);
468 /* This shouldn't return. If it returns, we have a problem */
469 status
= acpi_enter_sleep_state(ACPI_STATE_S4
);
470 /* Reprogram control registers and execute _BFS */
471 acpi_leave_sleep_state_prep(ACPI_STATE_S4
);
472 local_irq_restore(flags
);
474 return ACPI_SUCCESS(status
) ? 0 : -EFAULT
;
477 static void acpi_hibernation_finish(void)
479 hibernate_nvs_free();
483 static void acpi_hibernation_leave(void)
486 * If ACPI is not enabled by the BIOS and the boot kernel, we need to
490 /* Reprogram control registers and execute _BFS */
491 acpi_leave_sleep_state_prep(ACPI_STATE_S4
);
492 /* Check the hardware signature */
493 if (facs
&& s4_hardware_signature
!= facs
->hardware_signature
) {
494 printk(KERN_EMERG
"ACPI: Hardware changed while hibernated, "
496 panic("ACPI S4 hardware signature mismatch");
498 /* Restore the NVS memory area */
499 hibernate_nvs_restore();
502 static void acpi_pm_enable_gpes(void)
504 acpi_enable_all_runtime_gpes();
507 static struct platform_hibernation_ops acpi_hibernation_ops
= {
508 .begin
= acpi_hibernation_begin
,
510 .pre_snapshot
= acpi_hibernation_pre_snapshot
,
511 .finish
= acpi_hibernation_finish
,
512 .prepare
= acpi_pm_prepare
,
513 .enter
= acpi_hibernation_enter
,
514 .leave
= acpi_hibernation_leave
,
515 .pre_restore
= acpi_pm_disable_gpes
,
516 .restore_cleanup
= acpi_pm_enable_gpes
,
520 * acpi_hibernation_begin_old - Set the target system sleep state to
521 * ACPI_STATE_S4 and execute the _PTS control method. This
522 * function is used if the pre-ACPI 2.0 suspend ordering has been
525 static int acpi_hibernation_begin_old(void)
529 * The _TTS object should always be evaluated before the _PTS object.
530 * When the old_suspended_ordering is true, the _PTS object is
531 * evaluated in the acpi_sleep_prepare.
533 acpi_sleep_tts_switch(ACPI_STATE_S4
);
535 error
= acpi_sleep_prepare(ACPI_STATE_S4
);
539 error
= hibernate_nvs_alloc();
541 acpi_target_sleep_state
= ACPI_STATE_S4
;
546 static int acpi_hibernation_pre_snapshot_old(void)
548 int error
= acpi_pm_disable_gpes();
551 hibernate_nvs_save();
557 * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
560 static struct platform_hibernation_ops acpi_hibernation_ops_old
= {
561 .begin
= acpi_hibernation_begin_old
,
563 .pre_snapshot
= acpi_hibernation_pre_snapshot_old
,
564 .finish
= acpi_hibernation_finish
,
565 .prepare
= acpi_pm_disable_gpes
,
566 .enter
= acpi_hibernation_enter
,
567 .leave
= acpi_hibernation_leave
,
568 .pre_restore
= acpi_pm_disable_gpes
,
569 .restore_cleanup
= acpi_pm_enable_gpes
,
570 .recover
= acpi_pm_finish
,
572 #endif /* CONFIG_HIBERNATION */
574 int acpi_suspend(u32 acpi_state
)
576 suspend_state_t states
[] = {
577 [1] = PM_SUSPEND_STANDBY
,
578 [3] = PM_SUSPEND_MEM
,
582 if (acpi_state
< 6 && states
[acpi_state
])
583 return pm_suspend(states
[acpi_state
]);
589 #ifdef CONFIG_PM_SLEEP
591 * acpi_pm_device_sleep_state - return preferred power state of ACPI device
592 * in the system sleep state given by %acpi_target_sleep_state
593 * @dev: device to examine; its driver model wakeup flags control
594 * whether it should be able to wake up the system
595 * @d_min_p: used to store the upper limit of allowed states range
596 * Return value: preferred power state of the device on success, -ENODEV on
597 * failure (ie. if there's no 'struct acpi_device' for @dev)
599 * Find the lowest power (highest number) ACPI device power state that
600 * device @dev can be in while the system is in the sleep state represented
601 * by %acpi_target_sleep_state. If @wake is nonzero, the device should be
602 * able to wake up the system from this sleep state. If @d_min_p is set,
603 * the highest power (lowest number) device power state of @dev allowed
604 * in this system sleep state is stored at the location pointed to by it.
606 * The caller must ensure that @dev is valid before using this function.
607 * The caller is also responsible for figuring out if the device is
608 * supposed to be able to wake up the system and passing this information
612 int acpi_pm_device_sleep_state(struct device
*dev
, int *d_min_p
)
614 acpi_handle handle
= DEVICE_ACPI_HANDLE(dev
);
615 struct acpi_device
*adev
;
616 char acpi_method
[] = "_SxD";
617 unsigned long long d_min
, d_max
;
619 if (!handle
|| ACPI_FAILURE(acpi_bus_get_device(handle
, &adev
))) {
620 printk(KERN_DEBUG
"ACPI handle has no context!\n");
624 acpi_method
[2] = '0' + acpi_target_sleep_state
;
626 * If the sleep state is S0, we will return D3, but if the device has
627 * _S0W, we will use the value from _S0W
629 d_min
= ACPI_STATE_D0
;
630 d_max
= ACPI_STATE_D3
;
633 * If present, _SxD methods return the minimum D-state (highest power
634 * state) we can use for the corresponding S-states. Otherwise, the
635 * minimum D-state is D0 (ACPI 3.x).
637 * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
638 * provided -- that's our fault recovery, we ignore retval.
640 if (acpi_target_sleep_state
> ACPI_STATE_S0
)
641 acpi_evaluate_integer(handle
, acpi_method
, NULL
, &d_min
);
644 * If _PRW says we can wake up the system from the target sleep state,
645 * the D-state returned by _SxD is sufficient for that (we assume a
646 * wakeup-aware driver if wake is set). Still, if _SxW exists
647 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
648 * can wake the system. _S0W may be valid, too.
650 if (acpi_target_sleep_state
== ACPI_STATE_S0
||
651 (device_may_wakeup(dev
) && adev
->wakeup
.state
.enabled
&&
652 adev
->wakeup
.sleep_state
<= acpi_target_sleep_state
)) {
655 acpi_method
[3] = 'W';
656 status
= acpi_evaluate_integer(handle
, acpi_method
, NULL
,
658 if (ACPI_FAILURE(status
)) {
660 } else if (d_max
< d_min
) {
661 /* Warn the user of the broken DSDT */
662 printk(KERN_WARNING
"ACPI: Wrong value from %s\n",
675 * acpi_pm_device_sleep_wake - enable or disable the system wake-up
676 * capability of given device
677 * @dev: device to handle
678 * @enable: 'true' - enable, 'false' - disable the wake-up capability
680 int acpi_pm_device_sleep_wake(struct device
*dev
, bool enable
)
683 struct acpi_device
*adev
;
685 if (!device_may_wakeup(dev
))
688 handle
= DEVICE_ACPI_HANDLE(dev
);
689 if (!handle
|| ACPI_FAILURE(acpi_bus_get_device(handle
, &adev
))) {
690 printk(KERN_DEBUG
"ACPI handle has no context!\n");
695 acpi_enable_wakeup_device_power(adev
, acpi_target_sleep_state
) :
696 acpi_disable_wakeup_device_power(adev
);
700 static void acpi_power_off_prepare(void)
702 /* Prepare to power off the system */
703 acpi_sleep_prepare(ACPI_STATE_S5
);
704 acpi_disable_all_gpes();
707 static void acpi_power_off(void)
709 /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
710 printk(KERN_DEBUG
"%s called\n", __func__
);
712 acpi_enable_wakeup_device(ACPI_STATE_S5
);
713 acpi_enter_sleep_state(ACPI_STATE_S5
);
717 * ACPI 2.0 created the optional _GTS and _BFS,
718 * but industry adoption has been neither rapid nor broad.
720 * Linux gets into trouble when it executes poorly validated
721 * paths through the BIOS, so disable _GTS and _BFS by default,
722 * but do speak up and offer the option to enable them.
724 void __init
acpi_gts_bfs_check(void)
728 if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT
, METHOD_NAME__GTS
, &dummy
)))
730 printk(KERN_NOTICE PREFIX
"BIOS offers _GTS\n");
731 printk(KERN_NOTICE PREFIX
"If \"acpi.gts=1\" improves suspend, "
732 "please notify linux-acpi@vger.kernel.org\n");
734 if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT
, METHOD_NAME__BFS
, &dummy
)))
736 printk(KERN_NOTICE PREFIX
"BIOS offers _BFS\n");
737 printk(KERN_NOTICE PREFIX
"If \"acpi.bfs=1\" improves resume, "
738 "please notify linux-acpi@vger.kernel.org\n");
742 int __init
acpi_sleep_init(void)
746 #ifdef CONFIG_SUSPEND
749 dmi_check_system(acpisleep_dmi_table
);
755 sleep_states
[ACPI_STATE_S0
] = 1;
756 printk(KERN_INFO PREFIX
"(supports S0");
758 #ifdef CONFIG_SUSPEND
759 for (i
= ACPI_STATE_S1
; i
< ACPI_STATE_S4
; i
++) {
760 status
= acpi_get_sleep_type_data(i
, &type_a
, &type_b
);
761 if (ACPI_SUCCESS(status
)) {
767 suspend_set_ops(old_suspend_ordering
?
768 &acpi_suspend_ops_old
: &acpi_suspend_ops
);
771 #ifdef CONFIG_HIBERNATION
772 status
= acpi_get_sleep_type_data(ACPI_STATE_S4
, &type_a
, &type_b
);
773 if (ACPI_SUCCESS(status
)) {
774 hibernation_set_ops(old_suspend_ordering
?
775 &acpi_hibernation_ops_old
: &acpi_hibernation_ops
);
776 sleep_states
[ACPI_STATE_S4
] = 1;
779 acpi_get_table(ACPI_SIG_FACS
, 1,
780 (struct acpi_table_header
**)&facs
);
782 s4_hardware_signature
=
783 facs
->hardware_signature
;
787 status
= acpi_get_sleep_type_data(ACPI_STATE_S5
, &type_a
, &type_b
);
788 if (ACPI_SUCCESS(status
)) {
789 sleep_states
[ACPI_STATE_S5
] = 1;
791 pm_power_off_prepare
= acpi_power_off_prepare
;
792 pm_power_off
= acpi_power_off
;
796 * Register the tts_notifier to reboot notifier list so that the _TTS
797 * object can also be evaluated when the system enters S5.
799 register_reboot_notifier(&tts_notifier
);
800 acpi_gts_bfs_check();