sh: CPU hotplug support.

This adds preliminary support for CPU hotplug for SH SMP systems.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/kernel/idle.c

@@ -19,6 +19,7 @@
 #include <asm/pgalloc.h>
 #include <asm/system.h>
 #include <asm/atomic.h>
+#include <asm/smp.h>
 
 void (*pm_idle)(void) = NULL;
 
@@ -89,10 +90,13 @@ void cpu_idle(void)
 	while (1) {
 		tick_nohz_stop_sched_tick(1);
 
-		while (!need_resched() && cpu_online(cpu)) {
+		while (!need_resched()) {
 			check_pgt_cache();
 			rmb();
 
+			if (cpu_is_offline(cpu))
+				play_dead();
+
 			local_irq_disable();
 			/* Don't trace irqs off for idle */
 			stop_critical_timings();