xref: /linux/kernel/time/Kconfig (revision f37130533f68711fd6bae2c79950b8e72002bad6)
1#
2# Timer subsystem related configuration options
3#
4
5# Options selectable by arch Kconfig
6
7# Watchdog function for clocksources to detect instabilities
8config CLOCKSOURCE_WATCHDOG
9	bool
10
11# Architecture has extra clocksource data
12config ARCH_CLOCKSOURCE_DATA
13	bool
14
15# Platforms has a persistent clock
16config ALWAYS_USE_PERSISTENT_CLOCK
17	bool
18	default n
19
20# Timekeeping vsyscall support
21config GENERIC_TIME_VSYSCALL
22	bool
23
24# Timekeeping vsyscall support
25config GENERIC_TIME_VSYSCALL_OLD
26	bool
27
28# ktime_t scalar 64bit nsec representation
29config KTIME_SCALAR
30	bool
31
32# Old style timekeeping
33config ARCH_USES_GETTIMEOFFSET
34	bool
35
36# The generic clock events infrastructure
37config GENERIC_CLOCKEVENTS
38	bool
39
40# Migration helper. Builds, but does not invoke
41config GENERIC_CLOCKEVENTS_BUILD
42	bool
43	default y
44	depends on GENERIC_CLOCKEVENTS
45
46# Architecture can handle broadcast in a driver-agnostic way
47config ARCH_HAS_TICK_BROADCAST
48	bool
49
50# Clockevents broadcasting infrastructure
51config GENERIC_CLOCKEVENTS_BROADCAST
52	bool
53	depends on GENERIC_CLOCKEVENTS
54
55# Automatically adjust the min. reprogramming time for
56# clock event device
57config GENERIC_CLOCKEVENTS_MIN_ADJUST
58	bool
59
60# Generic update of CMOS clock
61config GENERIC_CMOS_UPDATE
62	bool
63
64if GENERIC_CLOCKEVENTS
65menu "Timers subsystem"
66
67# Core internal switch. Selected by NO_HZ / HIGH_RES_TIMERS. This is
68# only related to the tick functionality. Oneshot clockevent devices
69# are supported independ of this.
70config TICK_ONESHOT
71	bool
72
73config NO_HZ
74	bool "Tickless System (Dynamic Ticks)"
75	depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS
76	select TICK_ONESHOT
77	help
78	  This option enables a tickless system: timer interrupts will
79	  only trigger on an as-needed basis both when the system is
80	  busy and when the system is idle.
81
82config HIGH_RES_TIMERS
83	bool "High Resolution Timer Support"
84	depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS
85	select TICK_ONESHOT
86	help
87	  This option enables high resolution timer support. If your
88	  hardware is not capable then this option only increases
89	  the size of the kernel image.
90
91endmenu
92endif
93