v4.19.13 snapshot.
diff --git a/arch/sh/kernel/idle.c b/arch/sh/kernel/idle.c
new file mode 100644
index 0000000..be616ee
--- /dev/null
+++ b/arch/sh/kernel/idle.c
@@ -0,0 +1,61 @@
+/*
+ * The idle loop for all SuperH platforms.
+ *
+ * Copyright (C) 2002 - 2009 Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/pm.h>
+#include <linux/tick.h>
+#include <linux/preempt.h>
+#include <linux/thread_info.h>
+#include <linux/irqflags.h>
+#include <linux/smp.h>
+#include <linux/atomic.h>
+#include <asm/pgalloc.h>
+#include <asm/smp.h>
+#include <asm/bl_bit.h>
+
+static void (*sh_idle)(void);
+
+void default_idle(void)
+{
+ set_bl_bit();
+ local_irq_enable();
+ /* Isn't this racy ? */
+ cpu_sleep();
+ clear_bl_bit();
+}
+
+void arch_cpu_idle_dead(void)
+{
+ play_dead();
+}
+
+void arch_cpu_idle(void)
+{
+ sh_idle();
+}
+
+void __init select_idle_routine(void)
+{
+ /*
+ * If a platform has set its own idle routine, leave it alone.
+ */
+ if (!sh_idle)
+ sh_idle = default_idle;
+}
+
+void stop_this_cpu(void *unused)
+{
+ local_irq_disable();
+ set_cpu_online(smp_processor_id(), false);
+
+ for (;;)
+ cpu_sleep();
+}