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Diffstat (limited to 'kernel/power/Kconfig')
| -rw-r--r-- | kernel/power/Kconfig | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig new file mode 100644 index 0000000..23bd4da --- /dev/null +++ b/kernel/power/Kconfig @@ -0,0 +1,206 @@ +config PM + bool "Power Management support" + depends on !IA64_HP_SIM + ---help--- + "Power Management" means that parts of your computer are shut + off or put into a power conserving "sleep" mode if they are not + being used. There are two competing standards for doing this: APM + and ACPI. If you want to use either one, say Y here and then also + to the requisite support below. + + Power Management is most important for battery powered laptop + computers; if you have a laptop, check out the Linux Laptop home + page on the WWW at <http://www.linux-on-laptops.com/> or + Tuxmobil - Linux on Mobile Computers at <http://www.tuxmobil.org/> + and the Battery Powered Linux mini-HOWTO, available from + <http://www.tldp.org/docs.html#howto>. + + Note that, even if you say N here, Linux on the x86 architecture + will issue the hlt instruction if nothing is to be done, thereby + sending the processor to sleep and saving power. + +config PM_DEBUG + bool "Power Management Debug Support" + depends on PM + ---help--- + This option enables various debugging support in the Power Management + code. This is helpful when debugging and reporting PM bugs, like + suspend support. + +config PM_VERBOSE + bool "Verbose Power Management debugging" + depends on PM_DEBUG + default n + ---help--- + This option enables verbose messages from the Power Management code. + +config CAN_PM_TRACE + def_bool y + depends on PM_DEBUG && PM_SLEEP && EXPERIMENTAL + +config PM_TRACE + bool + help + This enables code to save the last PM event point across + reboot. The architecture needs to support this, x86 for + example does by saving things in the RTC, see below. + + The architecture specific code must provide the extern + functions from <linux/resume-trace.h> as well as the + <asm/resume-trace.h> header with a TRACE_RESUME() macro. + + The way the information is presented is architecture- + dependent, x86 will print the information during a + late_initcall. + +config PM_TRACE_RTC + bool "Suspend/resume event tracing" + depends on CAN_PM_TRACE + depends on X86 + select PM_TRACE + default n + ---help--- + This enables some cheesy code to save the last PM event point in the + RTC across reboots, so that you can debug a machine that just hangs + during suspend (or more commonly, during resume). + + To use this debugging feature you should attempt to suspend the + machine, reboot it and then run + + dmesg -s 1000000 | grep 'hash matches' + + CAUTION: this option will cause your machine's real-time clock to be + set to an invalid time after a resume. + +config PM_SLEEP_SMP + bool + depends on SMP + depends on ARCH_SUSPEND_POSSIBLE || ARCH_HIBERNATION_POSSIBLE + depends on PM_SLEEP + select HOTPLUG_CPU + default y + +config PM_SLEEP + bool + depends on SUSPEND || HIBERNATION || XEN_SAVE_RESTORE + default y + +config SUSPEND + bool "Suspend to RAM and standby" + depends on PM && ARCH_SUSPEND_POSSIBLE + default y + ---help--- + Allow the system to enter sleep states in which main memory is + powered and thus its contents are preserved, such as the + suspend-to-RAM state (e.g. the ACPI S3 state). + +config PM_TEST_SUSPEND + bool "Test suspend/resume and wakealarm during bootup" + depends on SUSPEND && PM_DEBUG && RTC_CLASS=y + ---help--- + This option will let you suspend your machine during bootup, and + make it wake up a few seconds later using an RTC wakeup alarm. + Enable this with a kernel parameter like "test_suspend=mem". + + You probably want to have your system's RTC driver statically + linked, ensuring that it's available when this test runs. + +config SUSPEND_FREEZER + bool "Enable freezer for suspend to RAM/standby" \ + if ARCH_WANTS_FREEZER_CONTROL || BROKEN + depends on SUSPEND + default y + help + This allows you to turn off the freezer for suspend. If this is + done, no tasks are frozen for suspend to RAM/standby. + + Turning OFF this setting is NOT recommended! If in doubt, say Y. + +config HIBERNATION + bool "Hibernation (aka 'suspend to disk')" + depends on PM && SWAP && ARCH_HIBERNATION_POSSIBLE + ---help--- + Enable the suspend to disk (STD) functionality, which is usually + called "hibernation" in user interfaces. STD checkpoints the + system and powers it off; and restores that checkpoint on reboot. + + You can suspend your machine with 'echo disk > /sys/power/state' + after placing resume=/dev/swappartition on the kernel command line + in your bootloader's configuration file. + + Alternatively, you can use the additional userland tools available + from <http://suspend.sf.net>. + + In principle it does not require ACPI or APM, although for example + ACPI will be used for the final steps when it is available. One + of the reasons to use software suspend is that the firmware hooks + for suspend states like suspend-to-RAM (STR) often don't work very + well with Linux. + + It creates an image which is saved in your active swap. Upon the next + boot, pass the 'resume=/dev/swappartition' argument to the kernel to + have it detect the saved image, restore memory state from it, and + continue to run as before. If you do not want the previous state to + be reloaded, then use the 'noresume' kernel command line argument. + Note, however, that fsck will be run on your filesystems and you will + need to run mkswap against the swap partition used for the suspend. + + It also works with swap files to a limited extent (for details see + <file:Documentation/power/swsusp-and-swap-files.txt>). + + Right now you may boot without resuming and resume later but in the + meantime you cannot use the swap partition(s)/file(s) involved in + suspending. Also in this case you must not use the filesystems + that were mounted before the suspend. In particular, you MUST NOT + MOUNT any journaled filesystems mounted before the suspend or they + will get corrupted in a nasty way. + + For more information take a look at <file:Documentation/power/swsusp.txt>. + +config PM_STD_PARTITION + string "Default resume partition" + depends on HIBERNATION + default "" + ---help--- + The default resume partition is the partition that the suspend- + to-disk implementation will look for a suspended disk image. + + The partition specified here will be different for almost every user. + It should be a valid swap partition (at least for now) that is turned + on before suspending. + + The partition specified can be overridden by specifying: + + resume=/dev/<other device> + + which will set the resume partition to the device specified. + + Note there is currently not a way to specify which device to save the + suspended image to. It will simply pick the first available swap + device. + +config APM_EMULATION + tristate "Advanced Power Management Emulation" + depends on PM && SYS_SUPPORTS_APM_EMULATION + help + APM is a BIOS specification for saving power using several different + techniques. This is mostly useful for battery powered laptops with + APM compliant BIOSes. If you say Y here, the system time will be + reset after a RESUME operation, the /proc/apm device will provide + battery status information, and user-space programs will receive + notification of APM "events" (e.g. battery status change). + + In order to use APM, you will need supporting software. For location + and more information, read <file:Documentation/power/pm.txt> and the + Battery Powered Linux mini-HOWTO, available from + <http://www.tldp.org/docs.html#howto>. + + This driver does not spin down disk drives (see the hdparm(8) + manpage ("man 8 hdparm") for that), and it doesn't turn off + VESA-compliant "green" monitors. + + Generally, if you don't have a battery in your machine, there isn't + much point in using this driver and you should say N. If you get + random kernel OOPSes or reboots that don't seem to be related to + anything, try disabling/enabling this option (or disabling/enabling + APM in your BIOS). |
