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, 178 insertions, 0 deletions

diff --git a/kernel/arch/arm/mach-dove/irq.c b/kernel/arch/arm/mach-dove/irq.c
new file mode 100644
index 000000000..4a5a7aedc
--- /dev/null
+++ b/kernel/arch/arm/mach-dove/irq.c
@@ -0,0 +1,178 @@
+/*
+ * arch/arm/mach-dove/irq.c
+ *
+ * Dove IRQ handling.
+ *
+ * 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/kernel.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/gpio.h>
+#include <linux/io.h>
+#include <asm/mach/arch.h>
+#include <plat/irq.h>
+#include <asm/mach/irq.h>
+#include <mach/pm.h>
+#include <mach/bridge-regs.h>
+#include <plat/orion-gpio.h>
+#include "common.h"
+
+static void pmu_irq_mask(struct irq_data *d)
+{
+	int pin = irq_to_pmu(d->irq);
+	u32 u;
+
+	u = readl(PMU_INTERRUPT_MASK);
+	u &= ~(1 << (pin & 31));
+	writel(u, PMU_INTERRUPT_MASK);
+}
+
+static void pmu_irq_unmask(struct irq_data *d)
+{
+	int pin = irq_to_pmu(d->irq);
+	u32 u;
+
+	u = readl(PMU_INTERRUPT_MASK);
+	u |= 1 << (pin & 31);
+	writel(u, PMU_INTERRUPT_MASK);
+}
+
+static void pmu_irq_ack(struct irq_data *d)
+{
+	int pin = irq_to_pmu(d->irq);
+	u32 u;
+
+	/*
+	 * The PMU mask register is not RW0C: it is RW.  This means that
+	 * the bits take whatever value is written to them; if you write
+	 * a '1', you will set the interrupt.
+	 *
+	 * Unfortunately this means there is NO race free way to clear
+	 * these interrupts.
+	 *
+	 * So, let's structure the code so that the window is as small as
+	 * possible.
+	 */
+	u = ~(1 << (pin & 31));
+	u &= readl_relaxed(PMU_INTERRUPT_CAUSE);
+	writel_relaxed(u, PMU_INTERRUPT_CAUSE);
+}
+
+static struct irq_chip pmu_irq_chip = {
+	.name		= "pmu_irq",
+	.irq_mask	= pmu_irq_mask,
+	.irq_unmask	= pmu_irq_unmask,
+	.irq_ack	= pmu_irq_ack,
+};
+
+static void pmu_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+	unsigned long cause = readl(PMU_INTERRUPT_CAUSE);
+
+	cause &= readl(PMU_INTERRUPT_MASK);
+	if (cause == 0) {
+		do_bad_IRQ(irq, desc);
+		return;
+	}
+
+	for (irq = 0; irq < NR_PMU_IRQS; irq++) {
+		if (!(cause & (1 << irq)))
+			continue;
+		irq = pmu_to_irq(irq);
+		generic_handle_irq(irq);
+	}
+}
+
+static int __initdata gpio0_irqs[4] = {
+	IRQ_DOVE_GPIO_0_7,
+	IRQ_DOVE_GPIO_8_15,
+	IRQ_DOVE_GPIO_16_23,
+	IRQ_DOVE_GPIO_24_31,
+};
+
+static int __initdata gpio1_irqs[4] = {
+	IRQ_DOVE_HIGH_GPIO,
+	0,
+	0,
+	0,
+};
+
+static int __initdata gpio2_irqs[4] = {
+	0,
+	0,
+	0,
+	0,
+};
+
+#ifdef CONFIG_MULTI_IRQ_HANDLER
+/*
+ * Compiling with both non-DT and DT support enabled, will
+ * break asm irq handler used by non-DT boards. Therefore,
+ * we provide a C-style irq handler even for non-DT boards,
+ * if MULTI_IRQ_HANDLER is set.
+ */
+
+static void __iomem *dove_irq_base = IRQ_VIRT_BASE;
+
+static asmlinkage void
+__exception_irq_entry dove_legacy_handle_irq(struct pt_regs *regs)
+{
+	u32 stat;
+
+	stat = readl_relaxed(dove_irq_base + IRQ_CAUSE_LOW_OFF);
+	stat &= readl_relaxed(dove_irq_base + IRQ_MASK_LOW_OFF);
+	if (stat) {
+		unsigned int hwirq = __fls(stat);
+		handle_IRQ(hwirq, regs);
+		return;
+	}
+	stat = readl_relaxed(dove_irq_base + IRQ_CAUSE_HIGH_OFF);
+	stat &= readl_relaxed(dove_irq_base + IRQ_MASK_HIGH_OFF);
+	if (stat) {
+		unsigned int hwirq = 32 + __fls(stat);
+		handle_IRQ(hwirq, regs);
+		return;
+	}
+}
+#endif
+
+void __init dove_init_irq(void)
+{
+	int i;
+
+	orion_irq_init(0, IRQ_VIRT_BASE + IRQ_MASK_LOW_OFF);
+	orion_irq_init(32, IRQ_VIRT_BASE + IRQ_MASK_HIGH_OFF);
+
+#ifdef CONFIG_MULTI_IRQ_HANDLER
+	set_handle_irq(dove_legacy_handle_irq);
+#endif
+
+	/*
+	 * Initialize gpiolib for GPIOs 0-71.
+	 */
+	orion_gpio_init(NULL, 0, 32, DOVE_GPIO_LO_VIRT_BASE, 0,
+			IRQ_DOVE_GPIO_START, gpio0_irqs);
+
+	orion_gpio_init(NULL, 32, 32, DOVE_GPIO_HI_VIRT_BASE, 0,
+			IRQ_DOVE_GPIO_START + 32, gpio1_irqs);
+
+	orion_gpio_init(NULL, 64, 8, DOVE_GPIO2_VIRT_BASE, 0,
+			IRQ_DOVE_GPIO_START + 64, gpio2_irqs);
+
+	/*
+	 * Mask and clear PMU interrupts
+	 */
+	writel(0, PMU_INTERRUPT_MASK);
+	writel(0, PMU_INTERRUPT_CAUSE);
+
+	for (i = IRQ_DOVE_PMU_START; i < NR_IRQS; i++) {
+		irq_set_chip_and_handler(i, &pmu_irq_chip, handle_level_irq);
+		irq_set_status_flags(i, IRQ_LEVEL);
+		set_irq_flags(i, IRQF_VALID);
+	}
+	irq_set_chained_handler(IRQ_DOVE_PMU, pmu_irq_handler);
+}