ICH3 and ICH4 have undocumented HPET capabilities. This patch enables
HPET for platforms based around these ICHs.
Tested on various ICH3 and ICH4 platforms.
Because HPET is not officially documented for ICH3/4 and may not have
been validated by chipset folks, we're on thin ice here. I'd recommend
testing this patch in -hrt or -mm for a while and wait for
success/failure reports before feeding it upstream.
tglx: depends on the force_hpet command line option !
Signed-off-by: Udo A. Steinberg <us15@os.inf.tu-dresden.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds quirks to force enable HPET on Via VT8235 and
VT8237 chipsets. The datasheet for 8237 documents HPET
functionality (although wrongly) whereas HPET is undocumented
for 8235.
Tested on A7V880 (8237) and K7VT4A+ (8235) boards.
tglx: depends on the force_hept commandline option
Signed-off-by: Udo A. Steinberg <us15@os.inf.tu-dresden.de>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Add another PCI ID for ICH7 force hpet.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
A bugfix in ich5 hpet force detect which caused resumes to fail. Thanks to
Udo A Steinberg for reporting the problem.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
force_enable hpet for ICH5.
[ Build fixes from Andrew Morton ]
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Force detect and/or enable HPET on ICH chipsets. This patch just handles the
detection part and following patches use this information. Adds a function to
repeat the force enabling during resume time.
Using HPET this way, instead of PIT increases the time CPUs can reside in
C-state when system is totally idle. On my test system with Core 2 Duo,
average C-state residency goes up from ~20mS to ~80mS.
[ Build fixed from Andrew Morton ]
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
