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-rw-r--r--arch/sh/kernel/idle.c81
1 files changed, 81 insertions, 0 deletions
diff --git a/arch/sh/kernel/idle.c b/arch/sh/kernel/idle.c
new file mode 100644
index 000000000000..fe59ccfc1152
--- /dev/null
+++ b/arch/sh/kernel/idle.c
@@ -0,0 +1,81 @@
+/*
+ * The idle loop for all SuperH platforms.
+ *
+ * Copyright (C) 2002 - 2008 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 <asm/pgalloc.h>
+#include <asm/system.h>
+#include <asm/atomic.h>
+
+static int hlt_counter;
+void (*pm_idle)(void);
+void (*pm_power_off)(void);
+EXPORT_SYMBOL(pm_power_off);
+
+static int __init nohlt_setup(char *__unused)
+{
+ hlt_counter = 1;
+ return 1;
+}
+__setup("nohlt", nohlt_setup);
+
+static int __init hlt_setup(char *__unused)
+{
+ hlt_counter = 0;
+ return 1;
+}
+__setup("hlt", hlt_setup);
+
+static void default_idle(void)
+{
+ if (!hlt_counter) {
+ clear_thread_flag(TIF_POLLING_NRFLAG);
+ smp_mb__after_clear_bit();
+ set_bl_bit();
+ stop_critical_timings();
+
+ while (!need_resched())
+ cpu_sleep();
+
+ start_critical_timings();
+ clear_bl_bit();
+ set_thread_flag(TIF_POLLING_NRFLAG);
+ } else
+ while (!need_resched())
+ cpu_relax();
+}
+
+void cpu_idle(void)
+{
+ set_thread_flag(TIF_POLLING_NRFLAG);
+
+ /* endless idle loop with no priority at all */
+ while (1) {
+ void (*idle)(void) = pm_idle;
+
+ if (!idle)
+ idle = default_idle;
+
+ tick_nohz_stop_sched_tick(1);
+ while (!need_resched())
+ idle();
+ tick_nohz_restart_sched_tick();
+
+ preempt_enable_no_resched();
+ schedule();
+ preempt_disable();
+ check_pgt_cache();
+ }
+}