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authorVenki Pallipadi2007-10-12 23:04:23 +0200
committerThomas Gleixner2007-10-12 23:04:23 +0200
commitd54bd57d6580250e6551261f3b15c45a9d90c77b (patch)
tree12cb06b4adb9494e67cefdc691643e333fef3b91 /include/asm-x86
parentx86: HPET restructure hpet code for hpet force enable (diff)
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x86: HPET force enable o ICH7 and later
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>
Diffstat (limited to 'include/asm-x86')
-rw-r--r--include/asm-x86/hpet.h1
1 files changed, 1 insertions, 0 deletions
diff --git a/include/asm-x86/hpet.h b/include/asm-x86/hpet.h
index 64446a9577dc..7c933242365f 100644
--- a/include/asm-x86/hpet.h
+++ b/include/asm-x86/hpet.h
@@ -66,6 +66,7 @@ extern unsigned long hpet_address;
extern int is_hpet_enabled(void);
extern int hpet_enable(void);
extern unsigned long hpet_readl(unsigned long a);
+extern void ich_force_hpet_resume(void);
#ifdef CONFIG_HPET_EMULATE_RTC