4 files changed, 34 insertions, 0 deletions

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 7c93c7eb0e5..d66a47fde80 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -87,6 +87,10 @@ config ARCH_HAS_ILOG2_U64
         bool
         default y if 64BIT
 
+config ARCH_HAS_CPU_IDLE_WAIT
+        bool
+        default y
+
 config GENERIC_HWEIGHT
         bool
         default y
diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index eb11a446720..811b7e74437 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -382,6 +382,8 @@ static inline unsigned long get_clean_sp(struct pt_regs *regs, int is_32)
 }
 #endif
 
+enum idle_boot_override {IDLE_NO_OVERRIDE = 0, IDLE_POWERSAVE_OFF};
+
 #endif /* __KERNEL__ */
 #endif /* __ASSEMBLY__ */
 #endif /* _ASM_POWERPC_PROCESSOR_H */
diff --git a/arch/powerpc/include/asm/system.h b/arch/powerpc/include/asm/system.h
index e30a13d1ee7..ff666803879 100644
--- a/arch/powerpc/include/asm/system.h
+++ b/arch/powerpc/include/asm/system.h
@@ -221,6 +221,7 @@ extern unsigned long klimit;
 extern void *zalloc_maybe_bootmem(size_t size, gfp_t mask);
 
 extern int powersave_nap;       /* set if nap mode can be used in idle loop */
+void cpu_idle_wait(void);
 
 /*
  * Atomic exchange
diff --git a/arch/powerpc/kernel/idle.c b/arch/powerpc/kernel/idle.c
index 39a2baa6ad5..8574b0e81ff 100644
--- a/arch/powerpc/kernel/idle.c
+++ b/arch/powerpc/kernel/idle.c
@@ -39,9 +39,13 @@
 #define cpu_should_die()        0
 #endif
 
+unsigned long cpuidle_disable = IDLE_NO_OVERRIDE;
+EXPORT_SYMBOL(cpuidle_disable);
+
 static int __init powersave_off(char *arg)
 {
         ppc_md.power_save = NULL;
+        cpuidle_disable = IDLE_POWERSAVE_OFF;
         return 0;
 }
 __setup("powersave=off", powersave_off);
@@ -102,6 +106,29 @@ void cpu_idle(void)
         }
 }
 
+
+/*
+ * cpu_idle_wait - Used to ensure that all the CPUs come out of the old
+ * idle loop and start using the new idle loop.
+ * Required while changing idle handler on SMP systems.
+ * Caller must have changed idle handler to the new value before the call.
+ * This window may be larger on shared systems.
+ */
+void cpu_idle_wait(void)
+{
+        int cpu;
+        smp_mb();
+
+        /* kick all the CPUs so that they exit out of old idle routine */
+        get_online_cpus();
+        for_each_online_cpu(cpu) {
+                if (cpu != smp_processor_id())
+                        smp_send_reschedule(cpu);
+        }
+        put_online_cpus();
+}
+EXPORT_SYMBOL_GPL(cpu_idle_wait);
+
 int powersave_nap;
 
 #ifdef CONFIG_SYSCTL