ACPI: Create "idle=halt" bootparam
"idle=halt" limits the idle loop to using
the halt instruction. No MWAIT, no IO accesses,
no C-states deeper than C1.
If something is broken in the idle code,
"idle=halt" is a less severe workaround
than "idle=poll" which disables all power savings.
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
diff --git a/include/asm-x86/processor.h b/include/asm-x86/processor.h
index 7f73827..bc22162 100644
--- a/include/asm-x86/processor.h
+++ b/include/asm-x86/processor.h
@@ -727,6 +727,7 @@
extern void select_idle_routine(const struct cpuinfo_x86 *c);
extern unsigned long boot_option_idle_override;
+extern unsigned long idle_halt;
extern void enable_sep_cpu(void);
extern int sysenter_setup(void);