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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-19 18:53:52 +08:00
linux-next/kernel/power
Rafael J. Wysocki a634cc1016 swsusp: introduce restore platform operations
At least on some machines it is necessary to prepare the ACPI firmware for the
restoration of the system memory state from the hibernation image if the
"platform" mode of hibernation has been used.  Namely, in that cases we need
to disable the GPEs before replacing the "boot" kernel with the "frozen"
kernel (cf.  http://bugzilla.kernel.org/show_bug.cgi?id=7887).  After the
restore they will be re-enabled by hibernation_ops->finish(), but if the
restore fails, they have to be re-enabled by the restore code explicitly.

For this purpose we can introduce two additional hibernation operations,
called pre_restore() and restore_cleanup() and call them from the restore code
path.  Still, they should be called if the "platform" mode of hibernation has
been used, so we need to pass the information about the hibernation mode from
the "frozen" kernel to the "boot" kernel in the image header.

Apparently, we can't drop the disabling of GPEs before the restore because of
Bug #7887 .   We also can't do it unconditionally, because the GPEs wouldn't
have been enabled after a successful restore if the suspend had been done in
the 'shutdown' or 'reboot' mode.

In principle we could (and probably should) unconditionally disable the GPEs
before each snapshot creation *and* before the restore, but then we'd have to
unconditionally enable them after the snapshot creation as well as after the
restore (or restore failure)   Still, for this purpose we'd need to modify
acpi_enter_sleep_state_prep() and acpi_leave_sleep_state() and we'd have to
introduce some mechanism synchronizing the disablind/enabling of the GPEs with
the device drivers' .suspend()/.resume() routines and with
disable_/enable_nonboot_cpus().   However, this would have affected the
suspend (ie.  s2ram) code as well as the hibernation, which I'd like to avoid
in this patch series.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:42 -07:00
..
console.c [PATCH] swsusp: fix suspend when console is in VT_AUTO+KD_GRAPHICS mode 2007-03-16 19:25:05 -07:00
disk.c swsusp: introduce restore platform operations 2007-07-19 10:04:42 -07:00
Kconfig PM: Do not require dev spew to get PM_DEBUG 2007-07-19 10:04:42 -07:00
main.c PM: introduce set_target method in pm_ops 2007-07-01 12:29:44 -07:00
Makefile [PATCH] Disable CPU hotplug during suspend 2006-09-26 08:48:59 -07:00
pm.c [PATCH] remove kernel/power/pm.c:pm_unregister_all() 2006-07-12 16:09:08 -07:00
power.h swsusp: introduce restore platform operations 2007-07-19 10:04:42 -07:00
poweroff.c WorkStruct: Pass the work_struct pointer instead of context data 2006-11-22 14:55:48 +00:00
process.c freezer: run show_state() when freezing times out 2007-07-19 10:04:42 -07:00
snapshot.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc 2007-05-09 12:56:01 -07:00
swap.c swsusp: introduce restore platform operations 2007-07-19 10:04:42 -07:00
swsusp.c swsusp: free more memory 2007-05-07 12:12:59 -07:00
user.c swsusp: introduce restore platform operations 2007-07-19 10:04:42 -07:00