Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 104 insertions, 0 deletions

diff --git a/kernel/arch/arm/mach-imx/cpuidle-imx6sx.c b/kernel/arch/arm/mach-imx/cpuidle-imx6sx.c
new file mode 100644
index 000000000..2c9f1a8bf
--- /dev/null
+++ b/kernel/arch/arm/mach-imx/cpuidle-imx6sx.c
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2014 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/cpuidle.h>
+#include <linux/cpu_pm.h>
+#include <linux/module.h>
+#include <asm/cpuidle.h>
+#include <asm/suspend.h>
+
+#include "common.h"
+#include "cpuidle.h"
+
+static int imx6sx_idle_finish(unsigned long val)
+{
+	cpu_do_idle();
+
+	return 0;
+}
+
+static int imx6sx_enter_wait(struct cpuidle_device *dev,
+			    struct cpuidle_driver *drv, int index)
+{
+	imx6q_set_lpm(WAIT_UNCLOCKED);
+
+	switch (index) {
+	case 1:
+		cpu_do_idle();
+		break;
+	case 2:
+		imx6_enable_rbc(true);
+		imx_gpc_set_arm_power_in_lpm(true);
+		imx_set_cpu_jump(0, v7_cpu_resume);
+		/* Need to notify there is a cpu pm operation. */
+		cpu_pm_enter();
+		cpu_cluster_pm_enter();
+
+		cpu_suspend(0, imx6sx_idle_finish);
+
+		cpu_cluster_pm_exit();
+		cpu_pm_exit();
+		imx_gpc_set_arm_power_in_lpm(false);
+		imx6_enable_rbc(false);
+		break;
+	default:
+		break;
+	}
+
+	imx6q_set_lpm(WAIT_CLOCKED);
+
+	return index;
+}
+
+static struct cpuidle_driver imx6sx_cpuidle_driver = {
+	.name = "imx6sx_cpuidle",
+	.owner = THIS_MODULE,
+	.states = {
+		/* WFI */
+		ARM_CPUIDLE_WFI_STATE,
+		/* WAIT */
+		{
+			.exit_latency = 50,
+			.target_residency = 75,
+			.flags = CPUIDLE_FLAG_TIMER_STOP,
+			.enter = imx6sx_enter_wait,
+			.name = "WAIT",
+			.desc = "Clock off",
+		},
+		/* WAIT + ARM power off  */
+		{
+			/*
+			 * ARM gating 31us * 5 + RBC clear 65us
+			 * and some margin for SW execution, here set it
+			 * to 300us.
+			 */
+			.exit_latency = 300,
+			.target_residency = 500,
+			.enter = imx6sx_enter_wait,
+			.name = "LOW-POWER-IDLE",
+			.desc = "ARM power off",
+		},
+	},
+	.state_count = 3,
+	.safe_state_index = 0,
+};
+
+int __init imx6sx_cpuidle_init(void)
+{
+	imx6_enable_rbc(false);
+	/*
+	 * set ARM power up/down timing to the fastest,
+	 * sw2iso and sw can be set to one 32K cycle = 31us
+	 * except for power up sw2iso which need to be
+	 * larger than LDO ramp up time.
+	 */
+	imx_gpc_set_arm_power_up_timing(2, 1);
+	imx_gpc_set_arm_power_down_timing(1, 1);
+
+	return cpuidle_register(&imx6sx_cpuidle_driver, NULL);
+}