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, 95 insertions, 0 deletions

diff --git a/kernel/arch/mips/txx9/rbtx4939/irq.c b/kernel/arch/mips/txx9/rbtx4939/irq.c
new file mode 100644
index 000000000..69a80616f
--- /dev/null
+++ b/kernel/arch/mips/txx9/rbtx4939/irq.c
@@ -0,0 +1,95 @@
+/*
+ * Toshiba RBTX4939 interrupt routines
+ * Based on linux/arch/mips/txx9/rbtx4938/irq.c,
+ *	    and RBTX49xx patch from CELF patch archive.
+ *
+ * Copyright (C) 2000-2001,2005-2006 Toshiba Corporation
+ * 2003-2005 (c) MontaVista Software, Inc. This file is licensed under the
+ * terms of the GNU General Public License version 2. This program is
+ * licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+ */
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <asm/mipsregs.h>
+#include <asm/txx9/rbtx4939.h>
+
+/*
+ * RBTX4939 IOC controller definition
+ */
+
+static void rbtx4939_ioc_irq_unmask(struct irq_data *d)
+{
+	int ioc_nr = d->irq - RBTX4939_IRQ_IOC;
+
+	writeb(readb(rbtx4939_ien_addr) | (1 << ioc_nr), rbtx4939_ien_addr);
+}
+
+static void rbtx4939_ioc_irq_mask(struct irq_data *d)
+{
+	int ioc_nr = d->irq - RBTX4939_IRQ_IOC;
+
+	writeb(readb(rbtx4939_ien_addr) & ~(1 << ioc_nr), rbtx4939_ien_addr);
+	mmiowb();
+}
+
+static struct irq_chip rbtx4939_ioc_irq_chip = {
+	.name		= "IOC",
+	.irq_mask	= rbtx4939_ioc_irq_mask,
+	.irq_unmask	= rbtx4939_ioc_irq_unmask,
+};
+
+
+static inline int rbtx4939_ioc_irqroute(void)
+{
+	unsigned char istat = readb(rbtx4939_ifac2_addr);
+
+	if (unlikely(istat == 0))
+		return -1;
+	return RBTX4939_IRQ_IOC + __fls8(istat);
+}
+
+static int rbtx4939_irq_dispatch(int pending)
+{
+	int irq;
+
+	if (pending & CAUSEF_IP7)
+		return MIPS_CPU_IRQ_BASE + 7;
+	irq = tx4939_irq();
+	if (likely(irq >= 0)) {
+		/* redirect IOC interrupts */
+		switch (irq) {
+		case RBTX4939_IRQ_IOCINT:
+			irq = rbtx4939_ioc_irqroute();
+			break;
+		}
+	} else if (pending & CAUSEF_IP0)
+		irq = MIPS_CPU_IRQ_BASE + 0;
+	else if (pending & CAUSEF_IP1)
+		irq = MIPS_CPU_IRQ_BASE + 1;
+	else
+		irq = -1;
+	return irq;
+}
+
+void __init rbtx4939_irq_setup(void)
+{
+	int i;
+
+	/* mask all IOC interrupts */
+	writeb(0, rbtx4939_ien_addr);
+
+	/* clear SoftInt interrupts */
+	writeb(0, rbtx4939_softint_addr);
+
+	txx9_irq_dispatch = rbtx4939_irq_dispatch;
+
+	tx4939_irq_init();
+	for (i = RBTX4939_IRQ_IOC;
+	     i < RBTX4939_IRQ_IOC + RBTX4939_NR_IRQ_IOC; i++)
+		irq_set_chip_and_handler(i, &rbtx4939_ioc_irq_chip,
+					 handle_level_irq);
+
+	irq_set_chained_handler(RBTX4939_IRQ_IOCINT, handle_simple_irq);
+}