Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | config PM |
| 2 | bool "Power Management support" |
Len Brown | eb7b6b3 | 2005-08-25 12:08:25 -0400 | [diff] [blame] | 3 | depends on !IA64_HP_SIM |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | ---help--- |
| 5 | "Power Management" means that parts of your computer are shut |
| 6 | off or put into a power conserving "sleep" mode if they are not |
| 7 | being used. There are two competing standards for doing this: APM |
| 8 | and ACPI. If you want to use either one, say Y here and then also |
| 9 | to the requisite support below. |
| 10 | |
| 11 | Power Management is most important for battery powered laptop |
| 12 | computers; if you have a laptop, check out the Linux Laptop home |
| 13 | page on the WWW at <http://www.linux-on-laptops.com/> or |
| 14 | Tuxmobil - Linux on Mobile Computers at <http://www.tuxmobil.org/> |
| 15 | and the Battery Powered Linux mini-HOWTO, available from |
| 16 | <http://www.tldp.org/docs.html#howto>. |
| 17 | |
| 18 | Note that, even if you say N here, Linux on the x86 architecture |
| 19 | will issue the hlt instruction if nothing is to be done, thereby |
| 20 | sending the processor to sleep and saving power. |
| 21 | |
| 22 | config PM_DEBUG |
| 23 | bool "Power Management Debug Support" |
| 24 | depends on PM |
| 25 | ---help--- |
Ben Collins | a034982 | 2007-07-19 01:47:27 -0700 | [diff] [blame] | 26 | This option enables various debugging support in the Power Management |
| 27 | code. This is helpful when debugging and reporting PM bugs, like |
| 28 | suspend support. |
| 29 | |
| 30 | config PM_VERBOSE |
| 31 | bool "Verbose Power Management debugging" |
| 32 | depends on PM_DEBUG |
| 33 | default n |
| 34 | ---help--- |
| 35 | This option enables verbose messages from the Power Management code. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | |
Johannes Berg | 90dda1c | 2007-11-19 23:46:16 +0100 | [diff] [blame] | 37 | config CAN_PM_TRACE |
| 38 | def_bool y |
| 39 | depends on PM_DEBUG && PM_SLEEP && EXPERIMENTAL |
| 40 | |
Linus Torvalds | eb71c87 | 2006-06-24 14:27:42 -0700 | [diff] [blame] | 41 | config PM_TRACE |
Johannes Berg | 90dda1c | 2007-11-19 23:46:16 +0100 | [diff] [blame] | 42 | bool |
| 43 | help |
| 44 | This enables code to save the last PM event point across |
| 45 | reboot. The architecture needs to support this, x86 for |
| 46 | example does by saving things in the RTC, see below. |
| 47 | |
| 48 | The architecture specific code must provide the extern |
| 49 | functions from <linux/resume-trace.h> as well as the |
| 50 | <asm/resume-trace.h> header with a TRACE_RESUME() macro. |
| 51 | |
| 52 | The way the information is presented is architecture- |
| 53 | dependent, x86 will print the information during a |
| 54 | late_initcall. |
| 55 | |
| 56 | config PM_TRACE_RTC |
Linus Torvalds | eb71c87 | 2006-06-24 14:27:42 -0700 | [diff] [blame] | 57 | bool "Suspend/resume event tracing" |
Johannes Berg | 90dda1c | 2007-11-19 23:46:16 +0100 | [diff] [blame] | 58 | depends on CAN_PM_TRACE |
| 59 | depends on X86 |
| 60 | select PM_TRACE |
Andrew Morton | 5c31f27 | 2006-06-27 02:53:26 -0700 | [diff] [blame] | 61 | default n |
Linus Torvalds | eb71c87 | 2006-06-24 14:27:42 -0700 | [diff] [blame] | 62 | ---help--- |
| 63 | This enables some cheesy code to save the last PM event point in the |
| 64 | RTC across reboots, so that you can debug a machine that just hangs |
| 65 | during suspend (or more commonly, during resume). |
| 66 | |
Pavel Machek | 23b168d | 2008-02-05 19:27:12 +0100 | [diff] [blame] | 67 | To use this debugging feature you should attempt to suspend the |
| 68 | machine, reboot it and then run |
Andrew Morton | 5c31f27 | 2006-06-27 02:53:26 -0700 | [diff] [blame] | 69 | |
| 70 | dmesg -s 1000000 | grep 'hash matches' |
| 71 | |
| 72 | CAUTION: this option will cause your machine's real-time clock to be |
| 73 | set to an invalid time after a resume. |
| 74 | |
Rafael J. Wysocki | f3de4be | 2007-08-30 23:56:29 -0700 | [diff] [blame] | 75 | config PM_SLEEP_SMP |
Rafael J. Wysocki | 296699d | 2007-07-29 23:27:18 +0200 | [diff] [blame] | 76 | bool |
Johannes Berg | 801e406 | 2007-12-08 02:12:39 +0100 | [diff] [blame] | 77 | depends on SMP |
Johannes Berg | f4cb570 | 2007-12-08 02:14:00 +0100 | [diff] [blame] | 78 | depends on ARCH_SUSPEND_POSSIBLE || ARCH_HIBERNATION_POSSIBLE |
Rafael J. Wysocki | f3de4be | 2007-08-30 23:56:29 -0700 | [diff] [blame] | 79 | depends on PM_SLEEP |
Rafael J. Wysocki | 296699d | 2007-07-29 23:27:18 +0200 | [diff] [blame] | 80 | select HOTPLUG_CPU |
| 81 | default y |
| 82 | |
| 83 | config PM_SLEEP |
| 84 | bool |
| 85 | depends on SUSPEND || HIBERNATION |
| 86 | default y |
| 87 | |
| 88 | config SUSPEND |
| 89 | bool "Suspend to RAM and standby" |
Johannes Berg | f4cb570 | 2007-12-08 02:14:00 +0100 | [diff] [blame] | 90 | depends on PM && ARCH_SUSPEND_POSSIBLE |
Rafael J. Wysocki | 296699d | 2007-07-29 23:27:18 +0200 | [diff] [blame] | 91 | default y |
| 92 | ---help--- |
| 93 | Allow the system to enter sleep states in which main memory is |
| 94 | powered and thus its contents are preserved, such as the |
Johannes Berg | f4cb570 | 2007-12-08 02:14:00 +0100 | [diff] [blame] | 95 | suspend-to-RAM state (e.g. the ACPI S3 state). |
Rafael J. Wysocki | 296699d | 2007-07-29 23:27:18 +0200 | [diff] [blame] | 96 | |
Johannes Berg | b28f508 | 2008-01-15 23:17:00 -0500 | [diff] [blame] | 97 | config SUSPEND_FREEZER |
| 98 | bool "Enable freezer for suspend to RAM/standby" \ |
| 99 | if ARCH_WANTS_FREEZER_CONTROL || BROKEN |
| 100 | depends on SUSPEND |
| 101 | default y |
| 102 | help |
| 103 | This allows you to turn off the freezer for suspend. If this is |
| 104 | done, no tasks are frozen for suspend to RAM/standby. |
| 105 | |
| 106 | Turning OFF this setting is NOT recommended! If in doubt, say Y. |
| 107 | |
Rafael J. Wysocki | b0cb1a1 | 2007-07-29 23:24:36 +0200 | [diff] [blame] | 108 | config HIBERNATION |
Rafael J. Wysocki | 296699d | 2007-07-29 23:27:18 +0200 | [diff] [blame] | 109 | bool "Hibernation (aka 'suspend to disk')" |
Johannes Berg | 801e406 | 2007-12-08 02:12:39 +0100 | [diff] [blame] | 110 | depends on PM && SWAP && ARCH_HIBERNATION_POSSIBLE |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 111 | ---help--- |
David Brownell | a7ee2e5 | 2007-05-06 14:50:50 -0700 | [diff] [blame] | 112 | Enable the suspend to disk (STD) functionality, which is usually |
| 113 | called "hibernation" in user interfaces. STD checkpoints the |
| 114 | system and powers it off; and restores that checkpoint on reboot. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 115 | |
Pavel Machek | 23b168d | 2008-02-05 19:27:12 +0100 | [diff] [blame] | 116 | You can suspend your machine with 'echo disk > /sys/power/state' |
| 117 | after placing resume=/dev/swappartition on the kernel command line |
| 118 | in your bootloader's configuration file. |
| 119 | |
Rafael J. Wysocki | c7276fd | 2007-03-06 01:42:24 -0800 | [diff] [blame] | 120 | Alternatively, you can use the additional userland tools available |
| 121 | from <http://suspend.sf.net>. |
| 122 | |
| 123 | In principle it does not require ACPI or APM, although for example |
David Brownell | a7ee2e5 | 2007-05-06 14:50:50 -0700 | [diff] [blame] | 124 | ACPI will be used for the final steps when it is available. One |
| 125 | of the reasons to use software suspend is that the firmware hooks |
| 126 | for suspend states like suspend-to-RAM (STR) often don't work very |
| 127 | well with Linux. |
Rafael J. Wysocki | c7276fd | 2007-03-06 01:42:24 -0800 | [diff] [blame] | 128 | |
| 129 | It creates an image which is saved in your active swap. Upon the next |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | boot, pass the 'resume=/dev/swappartition' argument to the kernel to |
| 131 | have it detect the saved image, restore memory state from it, and |
| 132 | continue to run as before. If you do not want the previous state to |
Rafael J. Wysocki | c7276fd | 2007-03-06 01:42:24 -0800 | [diff] [blame] | 133 | be reloaded, then use the 'noresume' kernel command line argument. |
| 134 | Note, however, that fsck will be run on your filesystems and you will |
| 135 | need to run mkswap against the swap partition used for the suspend. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | |
Rafael J. Wysocki | c7276fd | 2007-03-06 01:42:24 -0800 | [diff] [blame] | 137 | It also works with swap files to a limited extent (for details see |
| 138 | <file:Documentation/power/swsusp-and-swap-files.txt>). |
| 139 | |
| 140 | Right now you may boot without resuming and resume later but in the |
| 141 | meantime you cannot use the swap partition(s)/file(s) involved in |
| 142 | suspending. Also in this case you must not use the filesystems |
| 143 | that were mounted before the suspend. In particular, you MUST NOT |
| 144 | MOUNT any journaled filesystems mounted before the suspend or they |
| 145 | will get corrupted in a nasty way. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 146 | |
| 147 | For more information take a look at <file:Documentation/power/swsusp.txt>. |
| 148 | |
| 149 | config PM_STD_PARTITION |
| 150 | string "Default resume partition" |
Rafael J. Wysocki | b0cb1a1 | 2007-07-29 23:24:36 +0200 | [diff] [blame] | 151 | depends on HIBERNATION |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | default "" |
| 153 | ---help--- |
| 154 | The default resume partition is the partition that the suspend- |
| 155 | to-disk implementation will look for a suspended disk image. |
| 156 | |
| 157 | The partition specified here will be different for almost every user. |
| 158 | It should be a valid swap partition (at least for now) that is turned |
| 159 | on before suspending. |
| 160 | |
| 161 | The partition specified can be overridden by specifying: |
| 162 | |
| 163 | resume=/dev/<other device> |
| 164 | |
| 165 | which will set the resume partition to the device specified. |
| 166 | |
| 167 | Note there is currently not a way to specify which device to save the |
| 168 | suspended image to. It will simply pick the first available swap |
| 169 | device. |
| 170 | |
Ralf Baechle | 7726942 | 2007-02-09 17:08:57 +0000 | [diff] [blame] | 171 | config APM_EMULATION |
| 172 | tristate "Advanced Power Management Emulation" |
| 173 | depends on PM && SYS_SUPPORTS_APM_EMULATION |
| 174 | help |
| 175 | APM is a BIOS specification for saving power using several different |
| 176 | techniques. This is mostly useful for battery powered laptops with |
| 177 | APM compliant BIOSes. If you say Y here, the system time will be |
| 178 | reset after a RESUME operation, the /proc/apm device will provide |
| 179 | battery status information, and user-space programs will receive |
| 180 | notification of APM "events" (e.g. battery status change). |
| 181 | |
| 182 | In order to use APM, you will need supporting software. For location |
Randy Dunlap | 5347112 | 2008-03-12 18:10:51 -0400 | [diff] [blame] | 183 | and more information, read <file:Documentation/power/pm.txt> and the |
Ralf Baechle | 7726942 | 2007-02-09 17:08:57 +0000 | [diff] [blame] | 184 | Battery Powered Linux mini-HOWTO, available from |
| 185 | <http://www.tldp.org/docs.html#howto>. |
| 186 | |
| 187 | This driver does not spin down disk drives (see the hdparm(8) |
| 188 | manpage ("man 8 hdparm") for that), and it doesn't turn off |
| 189 | VESA-compliant "green" monitors. |
| 190 | |
| 191 | Generally, if you don't have a battery in your machine, there isn't |
| 192 | much point in using this driver and you should say N. If you get |
| 193 | random kernel OOPSes or reboots that don't seem to be related to |
| 194 | anything, try disabling/enabling this option (or disabling/enabling |
| 195 | APM in your BIOS). |