Mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ https://git.shady.money/linux/atom?h=v2.6.35 2010-07-25T03:26:22Z 2010-07-25T03:26:22Z Len Brown len.brown@intel.com 2010-07-25T03:26:22Z urn:sha1:0e1cf38889110a7188999388614aef17a84d9d25 2010-07-25T03:26:09Z Rafael J. Wysocki rjw@sisk.pl 2010-07-23T20:59:09Z urn:sha1:72ad5d77fb981963edae15eee8196c80238f5ed0 Commit 2a6b69765ad794389f2fc3e14a0afa1a995221c2 (ACPI: Store NVS state even when entering suspend to RAM) caused the ACPI suspend code save the NVS area during suspend and restore it during resume unconditionally, although it is known that some systems need to use acpi_sleep=s4_nonvs for hibernation to work. To allow the affected systems to avoid saving and restoring the NVS area during suspend to RAM and resume, introduce kernel command line option acpi_sleep=nonvs and make acpi_sleep=s4_nonvs work as its alias temporarily (add acpi_sleep=s4_nonvs to the feature removal file). Addresses https://bugzilla.kernel.org/show_bug.cgi?id=16396 . Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reported-and-tested-by: tomas m <tmezzadra@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com> 2010-07-22T22:19:12Z Len Brown len.brown@intel.com 2010-07-22T22:19:12Z urn:sha1:bbac30edb39a80426e4a3420a5ec635eb4466f63 2010-07-22T22:18:28Z Len Brown len.brown@intel.com 2010-07-22T22:18:28Z urn:sha1:4a973f2495fba8775d1c408b3ee7f2c19b19f13f 2010-07-22T22:18:18Z Len Brown len.brown@intel.com 2010-07-22T22:18:18Z urn:sha1:be48b11573952b467676b24de87d637e33339e7d 2010-07-22T22:18:05Z Len Brown len.brown@intel.com 2010-07-22T22:18:05Z urn:sha1:27568d8e5f7a038795dff997a906f775084f927a 2010-07-22T22:17:39Z Len Brown len.brown@intel.com 2010-07-22T22:17:39Z urn:sha1:855977ef6d07e8d1d50994ab7310e40d18a64e16 2010-07-22T21:23:10Z Len Brown len.brown@intel.com 2010-07-22T21:23:10Z urn:sha1:d3e7e99f2faf9f44ec0a3379f735b41c9173dfa1 processor.bm_check_disable=1" prevents Linux from checking BM_STS before entering C3-type cpu power states. This may be useful for a system running acpi_idle where the BIOS exports FADT C-states, _CST IO C-states, or _CST FFH C-states with the BM_STS bit set; while configuring the chipset to set BM_STS more frequently than perhaps is optimal. Note that such systems may have been developed using a tickful OS that would quickly clear BM_STS, rather than a tickless OS that may go for some time between checking and clearing BM_STS. Note also that an alternative for newer systems is to use the intel_idle driver, which always ignores BM_STS, relying Linux device drivers to register constraints explicitly via PM_QOS. https://bugzilla.kernel.org/show_bug.cgi?id=15886 Signed-off-by: Len Brown <len.brown@intel.com> 2010-07-22T20:54:27Z Len Brown len.brown@intel.com 2010-07-22T20:54:27Z urn:sha1:718be4aaf3613cf7c2d097f925abc3d3553c0605 It turns out that there is a bit in the _CST for Intel FFH C3 that tells the OS if we should be checking BM_STS or not. Linux has been unconditionally checking BM_STS. If the chip-set is configured to enable BM_STS, it can retard or completely prevent entry into deep C-states -- as illustrated by turbostat: http://userweb.kernel.org/~lenb/acpi/utils/pmtools/turbostat/ ref: Intel Processor Vendor-Specific ACPI Interface Specification table 4 "_CST FFH GAS Field Encoding" Bit 1: Set to 1 if OSPM should use Bus Master avoidance for this C-state https://bugzilla.kernel.org/show_bug.cgi?id=15886 Signed-off-by: Len Brown <len.brown@intel.com> 2010-07-21T15:30:09Z KOSAKI Motohiro kosaki.motohiro@jp.fujitsu.com 2010-07-20T22:18:35Z urn:sha1:6c9c0fd062a6540dbee233151679b5f03ce433d9 CONFIG_ACPI_PROCFS=n: drivers/acpi/processor_idle.c:83: warning: 'us_to_pm_timer_ticks' defined but not used. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>