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diff --git a/arch/powerpc/platforms/52xx/mpc52xx_pic.c b/arch/powerpc/platforms/52xx/mpc52xx_pic.c
new file mode 100644
index 000000000..2944bc84b
--- /dev/null
+++ b/arch/powerpc/platforms/52xx/mpc52xx_pic.c
@@ -0,0 +1,518 @@
+/*
+ *
+ * Programmable Interrupt Controller functions for the Freescale MPC52xx.
+ *
+ * Copyright (C) 2008 Secret Lab Technologies Ltd.
+ * Copyright (C) 2006 bplan GmbH
+ * Copyright (C) 2004 Sylvain Munaut <tnt@246tNt.com>
+ * Copyright (C) 2003 Montavista Software, Inc
+ *
+ * Based on the code from the 2.4 kernel by
+ * Dale Farnsworth <dfarnsworth@mvista.com> and Kent Borg.
+ *
+ * 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.
+ *
+ */
+
+/*
+ * This is the device driver for the MPC5200 interrupt controller.
+ *
+ * hardware overview
+ * -----------------
+ * The MPC5200 interrupt controller groups the all interrupt sources into
+ * three groups called 'critical', 'main', and 'peripheral'.  The critical
+ * group has 3 irqs, External IRQ0, slice timer 0 irq, and wake from deep
+ * sleep.  Main group include the other 3 external IRQs, slice timer 1, RTC,
+ * gpios, and the general purpose timers.  Peripheral group contains the
+ * remaining irq sources from all of the on-chip peripherals (PSCs, Ethernet,
+ * USB, DMA, etc).
+ *
+ * virqs
+ * -----
+ * The Linux IRQ subsystem requires that each irq source be assigned a
+ * system wide unique IRQ number starting at 1 (0 means no irq).  Since
+ * systems can have multiple interrupt controllers, the virtual IRQ (virq)
+ * infrastructure lets each interrupt controller to define a local set
+ * of IRQ numbers and the virq infrastructure maps those numbers into
+ * a unique range of the global IRQ# space.
+ *
+ * To define a range of virq numbers for this controller, this driver first
+ * assigns a number to each of the irq groups (called the level 1 or L1
+ * value).  Within each group individual irq sources are also assigned a
+ * number, as defined by the MPC5200 user guide, and refers to it as the
+ * level 2 or L2 value.  The virq number is determined by shifting up the
+ * L1 value by MPC52xx_IRQ_L1_OFFSET and ORing it with the L2 value.
+ *
+ * For example, the TMR0 interrupt is irq 9 in the main group.  The
+ * virq for TMR0 is calculated by ((1 << MPC52xx_IRQ_L1_OFFSET) | 9).
+ *
+ * The observant reader will also notice that this driver defines a 4th
+ * interrupt group called 'bestcomm'.  The bestcomm group isn't physically
+ * part of the MPC5200 interrupt controller, but it is used here to assign
+ * a separate virq number for each bestcomm task (since any of the 16
+ * bestcomm tasks can cause the bestcomm interrupt to be raised).  When a
+ * bestcomm interrupt occurs (peripheral group, irq 0) this driver determines
+ * which task needs servicing and returns the irq number for that task.  This
+ * allows drivers which use bestcomm to define their own interrupt handlers.
+ *
+ * irq_chip structures
+ * -------------------
+ * For actually manipulating IRQs (masking, enabling, clearing, etc) this
+ * driver defines four separate 'irq_chip' structures, one for the main
+ * group, one for the peripherals group, one for the bestcomm group and one
+ * for external interrupts.  The irq_chip structures provide the hooks needed
+ * to manipulate each IRQ source, and since each group is has a separate set
+ * of registers for controlling the irq, it makes sense to divide up the
+ * hooks along those lines.
+ *
+ * You'll notice that there is not an irq_chip for the critical group and
+ * you'll also notice that there is an irq_chip defined for external
+ * interrupts even though there is no external interrupt group.  The reason
+ * for this is that the four external interrupts are all managed with the same
+ * register even though one of the external IRQs is in the critical group and
+ * the other three are in the main group.  For this reason it makes sense for
+ * the 4 external irqs to be managed using a separate set of hooks.  The
+ * reason there is no crit irq_chip is that of the 3 irqs in the critical
+ * group, only external interrupt is actually support at this time by this
+ * driver and since external interrupt is the only one used, it can just
+ * be directed to make use of the external irq irq_chip.
+ *
+ * device tree bindings
+ * --------------------
+ * The device tree bindings for this controller reflect the two level
+ * organization of irqs in the device.  #interrupt-cells = <3> where the
+ * first cell is the group number [0..3], the second cell is the irq
+ * number in the group, and the third cell is the sense type (level/edge).
+ * For reference, the following is a list of the interrupt property values
+ * associated with external interrupt sources on the MPC5200 (just because
+ * it is non-obvious to determine what the interrupts property should be
+ * when reading the mpc5200 manual and it is a frequently asked question).
+ *
+ * External interrupts:
+ * <0 0 n>	external irq0, n is sense	(n=0: level high,
+ * <1 1 n>	external irq1, n is sense	 n=1: edge rising,
+ * <1 2 n>	external irq2, n is sense	 n=2: edge falling,
+ * <1 3 n>	external irq3, n is sense	 n=3: level low)
+ */
+#undef DEBUG
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <asm/io.h>
+#include <asm/prom.h>
+#include <asm/mpc52xx.h>
+
+/* HW IRQ mapping */
+#define MPC52xx_IRQ_L1_CRIT	(0)
+#define MPC52xx_IRQ_L1_MAIN	(1)
+#define MPC52xx_IRQ_L1_PERP	(2)
+#define MPC52xx_IRQ_L1_SDMA	(3)
+
+#define MPC52xx_IRQ_L1_OFFSET	(6)
+#define MPC52xx_IRQ_L1_MASK	(0x00c0)
+#define MPC52xx_IRQ_L2_MASK	(0x003f)
+
+#define MPC52xx_IRQ_HIGHTESTHWIRQ (0xd0)
+
+
+/* MPC5200 device tree match tables */
+static const struct of_device_id mpc52xx_pic_ids[] __initconst = {
+	{ .compatible = "fsl,mpc5200-pic", },
+	{ .compatible = "mpc5200-pic", },
+	{}
+};
+static const struct of_device_id mpc52xx_sdma_ids[] __initconst = {
+	{ .compatible = "fsl,mpc5200-bestcomm", },
+	{ .compatible = "mpc5200-bestcomm", },
+	{}
+};
+
+static struct mpc52xx_intr __iomem *intr;
+static struct mpc52xx_sdma __iomem *sdma;
+static struct irq_domain *mpc52xx_irqhost = NULL;
+
+static unsigned char mpc52xx_map_senses[4] = {
+	IRQ_TYPE_LEVEL_HIGH,
+	IRQ_TYPE_EDGE_RISING,
+	IRQ_TYPE_EDGE_FALLING,
+	IRQ_TYPE_LEVEL_LOW,
+};
+
+/* Utility functions */
+static inline void io_be_setbit(u32 __iomem *addr, int bitno)
+{
+	out_be32(addr, in_be32(addr) | (1 << bitno));
+}
+
+static inline void io_be_clrbit(u32 __iomem *addr, int bitno)
+{
+	out_be32(addr, in_be32(addr) & ~(1 << bitno));
+}
+
+/*
+ * IRQ[0-3] interrupt irq_chip
+ */
+static void mpc52xx_extirq_mask(struct irq_data *d)
+{
+	int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK;
+	io_be_clrbit(&intr->ctrl, 11 - l2irq);
+}
+
+static void mpc52xx_extirq_unmask(struct irq_data *d)
+{
+	int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK;
+	io_be_setbit(&intr->ctrl, 11 - l2irq);
+}
+
+static void mpc52xx_extirq_ack(struct irq_data *d)
+{
+	int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK;
+	io_be_setbit(&intr->ctrl, 27-l2irq);
+}
+
+static int mpc52xx_extirq_set_type(struct irq_data *d, unsigned int flow_type)
+{
+	u32 ctrl_reg, type;
+	int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK;
+	void *handler = handle_level_irq;
+
+	pr_debug("%s: irq=%x. l2=%d flow_type=%d\n", __func__,
+		(int) irqd_to_hwirq(d), l2irq, flow_type);
+
+	switch (flow_type) {
+	case IRQF_TRIGGER_HIGH: type = 0; break;
+	case IRQF_TRIGGER_RISING: type = 1; handler = handle_edge_irq; break;
+	case IRQF_TRIGGER_FALLING: type = 2; handler = handle_edge_irq; break;
+	case IRQF_TRIGGER_LOW: type = 3; break;
+	default:
+		type = 0;
+	}
+
+	ctrl_reg = in_be32(&intr->ctrl);
+	ctrl_reg &= ~(0x3 << (22 - (l2irq * 2)));
+	ctrl_reg |= (type << (22 - (l2irq * 2)));
+	out_be32(&intr->ctrl, ctrl_reg);
+
+	__irq_set_handler_locked(d->irq, handler);
+
+	return 0;
+}
+
+static struct irq_chip mpc52xx_extirq_irqchip = {
+	.name = "MPC52xx External",
+	.irq_mask = mpc52xx_extirq_mask,
+	.irq_unmask = mpc52xx_extirq_unmask,
+	.irq_ack = mpc52xx_extirq_ack,
+	.irq_set_type = mpc52xx_extirq_set_type,
+};
+
+/*
+ * Main interrupt irq_chip
+ */
+static int mpc52xx_null_set_type(struct irq_data *d, unsigned int flow_type)
+{
+	return 0; /* Do nothing so that the sense mask will get updated */
+}
+
+static void mpc52xx_main_mask(struct irq_data *d)
+{
+	int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK;
+	io_be_setbit(&intr->main_mask, 16 - l2irq);
+}
+
+static void mpc52xx_main_unmask(struct irq_data *d)
+{
+	int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK;
+	io_be_clrbit(&intr->main_mask, 16 - l2irq);
+}
+
+static struct irq_chip mpc52xx_main_irqchip = {
+	.name = "MPC52xx Main",
+	.irq_mask = mpc52xx_main_mask,
+	.irq_mask_ack = mpc52xx_main_mask,
+	.irq_unmask = mpc52xx_main_unmask,
+	.irq_set_type = mpc52xx_null_set_type,
+};
+
+/*
+ * Peripherals interrupt irq_chip
+ */
+static void mpc52xx_periph_mask(struct irq_data *d)
+{
+	int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK;
+	io_be_setbit(&intr->per_mask, 31 - l2irq);
+}
+
+static void mpc52xx_periph_unmask(struct irq_data *d)
+{
+	int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK;
+	io_be_clrbit(&intr->per_mask, 31 - l2irq);
+}
+
+static struct irq_chip mpc52xx_periph_irqchip = {
+	.name = "MPC52xx Peripherals",
+	.irq_mask = mpc52xx_periph_mask,
+	.irq_mask_ack = mpc52xx_periph_mask,
+	.irq_unmask = mpc52xx_periph_unmask,
+	.irq_set_type = mpc52xx_null_set_type,
+};
+
+/*
+ * SDMA interrupt irq_chip
+ */
+static void mpc52xx_sdma_mask(struct irq_data *d)
+{
+	int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK;
+	io_be_setbit(&sdma->IntMask, l2irq);
+}
+
+static void mpc52xx_sdma_unmask(struct irq_data *d)
+{
+	int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK;
+	io_be_clrbit(&sdma->IntMask, l2irq);
+}
+
+static void mpc52xx_sdma_ack(struct irq_data *d)
+{
+	int l2irq = irqd_to_hwirq(d) & MPC52xx_IRQ_L2_MASK;
+	out_be32(&sdma->IntPend, 1 << l2irq);
+}
+
+static struct irq_chip mpc52xx_sdma_irqchip = {
+	.name = "MPC52xx SDMA",
+	.irq_mask = mpc52xx_sdma_mask,
+	.irq_unmask = mpc52xx_sdma_unmask,
+	.irq_ack = mpc52xx_sdma_ack,
+	.irq_set_type = mpc52xx_null_set_type,
+};
+
+/**
+ * mpc52xx_is_extirq - Returns true if hwirq number is for an external IRQ
+ */
+static int mpc52xx_is_extirq(int l1, int l2)
+{
+	return ((l1 == 0) && (l2 == 0)) ||
+	       ((l1 == 1) && (l2 >= 1) && (l2 <= 3));
+}
+
+/**
+ * mpc52xx_irqhost_xlate - translate virq# from device tree interrupts property
+ */
+static int mpc52xx_irqhost_xlate(struct irq_domain *h, struct device_node *ct,
+				 const u32 *intspec, unsigned int intsize,
+				 irq_hw_number_t *out_hwirq,
+				 unsigned int *out_flags)
+{
+	int intrvect_l1;
+	int intrvect_l2;
+	int intrvect_type;
+	int intrvect_linux;
+
+	if (intsize != 3)
+		return -1;
+
+	intrvect_l1 = (int)intspec[0];
+	intrvect_l2 = (int)intspec[1];
+	intrvect_type = (int)intspec[2] & 0x3;
+
+	intrvect_linux = (intrvect_l1 << MPC52xx_IRQ_L1_OFFSET) &
+			 MPC52xx_IRQ_L1_MASK;
+	intrvect_linux |= intrvect_l2 & MPC52xx_IRQ_L2_MASK;
+
+	*out_hwirq = intrvect_linux;
+	*out_flags = IRQ_TYPE_LEVEL_LOW;
+	if (mpc52xx_is_extirq(intrvect_l1, intrvect_l2))
+		*out_flags = mpc52xx_map_senses[intrvect_type];
+
+	pr_debug("return %x, l1=%d, l2=%d\n", intrvect_linux, intrvect_l1,
+		 intrvect_l2);
+	return 0;
+}
+
+/**
+ * mpc52xx_irqhost_map - Hook to map from virq to an irq_chip structure
+ */
+static int mpc52xx_irqhost_map(struct irq_domain *h, unsigned int virq,
+			       irq_hw_number_t irq)
+{
+	int l1irq;
+	int l2irq;
+	struct irq_chip *uninitialized_var(irqchip);
+	void *hndlr;
+	int type;
+	u32 reg;
+
+	l1irq = (irq & MPC52xx_IRQ_L1_MASK) >> MPC52xx_IRQ_L1_OFFSET;
+	l2irq = irq & MPC52xx_IRQ_L2_MASK;
+
+	/*
+	 * External IRQs are handled differently by the hardware so they are
+	 * handled by a dedicated irq_chip structure.
+	 */
+	if (mpc52xx_is_extirq(l1irq, l2irq)) {
+		reg = in_be32(&intr->ctrl);
+		type = mpc52xx_map_senses[(reg >> (22 - l2irq * 2)) & 0x3];
+		if ((type == IRQ_TYPE_EDGE_FALLING) ||
+		    (type == IRQ_TYPE_EDGE_RISING))
+			hndlr = handle_edge_irq;
+		else
+			hndlr = handle_level_irq;
+
+		irq_set_chip_and_handler(virq, &mpc52xx_extirq_irqchip, hndlr);
+		pr_debug("%s: External IRQ%i virq=%x, hw=%x. type=%x\n",
+			 __func__, l2irq, virq, (int)irq, type);
+		return 0;
+	}
+
+	/* It is an internal SOC irq.  Choose the correct irq_chip */
+	switch (l1irq) {
+	case MPC52xx_IRQ_L1_MAIN: irqchip = &mpc52xx_main_irqchip; break;
+	case MPC52xx_IRQ_L1_PERP: irqchip = &mpc52xx_periph_irqchip; break;
+	case MPC52xx_IRQ_L1_SDMA: irqchip = &mpc52xx_sdma_irqchip; break;
+	case MPC52xx_IRQ_L1_CRIT:
+		pr_warn("%s: Critical IRQ #%d is unsupported! Nopping it.\n",
+			__func__, l2irq);
+		irq_set_chip(virq, &no_irq_chip);
+		return 0;
+	}
+
+	irq_set_chip_and_handler(virq, irqchip, handle_level_irq);
+	pr_debug("%s: virq=%x, l1=%i, l2=%i\n", __func__, virq, l1irq, l2irq);
+
+	return 0;
+}
+
+static const struct irq_domain_ops mpc52xx_irqhost_ops = {
+	.xlate = mpc52xx_irqhost_xlate,
+	.map = mpc52xx_irqhost_map,
+};
+
+/**
+ * mpc52xx_init_irq - Initialize and register with the virq subsystem
+ *
+ * Hook for setting up IRQs on an mpc5200 system.  A pointer to this function
+ * is to be put into the machine definition structure.
+ *
+ * This function searches the device tree for an MPC5200 interrupt controller,
+ * initializes it, and registers it with the virq subsystem.
+ */
+void __init mpc52xx_init_irq(void)
+{
+	u32 intr_ctrl;
+	struct device_node *picnode;
+	struct device_node *np;
+
+	/* Remap the necessary zones */
+	picnode = of_find_matching_node(NULL, mpc52xx_pic_ids);
+	intr = of_iomap(picnode, 0);
+	if (!intr)
+		panic(__FILE__	": find_and_map failed on 'mpc5200-pic'. "
+				"Check node !");
+
+	np = of_find_matching_node(NULL, mpc52xx_sdma_ids);
+	sdma = of_iomap(np, 0);
+	of_node_put(np);
+	if (!sdma)
+		panic(__FILE__	": find_and_map failed on 'mpc5200-bestcomm'. "
+				"Check node !");
+
+	pr_debug("MPC5200 IRQ controller mapped to 0x%p\n", intr);
+
+	/* Disable all interrupt sources. */
+	out_be32(&sdma->IntPend, 0xffffffff);	/* 1 means clear pending */
+	out_be32(&sdma->IntMask, 0xffffffff);	/* 1 means disabled */
+	out_be32(&intr->per_mask, 0x7ffffc00);	/* 1 means disabled */
+	out_be32(&intr->main_mask, 0x00010fff);	/* 1 means disabled */
+	intr_ctrl = in_be32(&intr->ctrl);
+	intr_ctrl &= 0x00ff0000;	/* Keeps IRQ[0-3] config */
+	intr_ctrl |=	0x0f000000 |	/* clear IRQ 0-3 */
+			0x00001000 |	/* MEE master external enable */
+			0x00000000 |	/* 0 means disable IRQ 0-3 */
+			0x00000001;	/* CEb route critical normally */
+	out_be32(&intr->ctrl, intr_ctrl);
+
+	/* Zero a bunch of the priority settings. */
+	out_be32(&intr->per_pri1, 0);
+	out_be32(&intr->per_pri2, 0);
+	out_be32(&intr->per_pri3, 0);
+	out_be32(&intr->main_pri1, 0);
+	out_be32(&intr->main_pri2, 0);
+
+	/*
+	 * As last step, add an irq host to translate the real
+	 * hw irq information provided by the ofw to linux virq
+	 */
+	mpc52xx_irqhost = irq_domain_add_linear(picnode,
+	                                 MPC52xx_IRQ_HIGHTESTHWIRQ,
+	                                 &mpc52xx_irqhost_ops, NULL);
+
+	if (!mpc52xx_irqhost)
+		panic(__FILE__ ": Cannot allocate the IRQ host\n");
+
+	irq_set_default_host(mpc52xx_irqhost);
+
+	pr_info("MPC52xx PIC is up and running!\n");
+}
+
+/**
+ * mpc52xx_get_irq - Get pending interrupt number hook function
+ *
+ * Called by the interrupt handler to determine what IRQ handler needs to be
+ * executed.
+ *
+ * Status of pending interrupts is determined by reading the encoded status
+ * register.  The encoded status register has three fields; one for each of the
+ * types of interrupts defined by the controller - 'critical', 'main' and
+ * 'peripheral'.  This function reads the status register and returns the IRQ
+ * number associated with the highest priority pending interrupt.  'Critical'
+ * interrupts have the highest priority, followed by 'main' interrupts, and
+ * then 'peripheral'.
+ *
+ * The mpc5200 interrupt controller can be configured to boost the priority
+ * of individual 'peripheral' interrupts.  If this is the case then a special
+ * value will appear in either the crit or main fields indicating a high
+ * or medium priority peripheral irq has occurred.
+ *
+ * This function checks each of the 3 irq request fields and returns the
+ * first pending interrupt that it finds.
+ *
+ * This function also identifies a 4th type of interrupt; 'bestcomm'.  Each
+ * bestcomm DMA task can raise the bestcomm peripheral interrupt.  When this
+ * occurs at task-specific IRQ# is decoded so that each task can have its
+ * own IRQ handler.
+ */
+unsigned int mpc52xx_get_irq(void)
+{
+	u32 status;
+	int irq;
+
+	status = in_be32(&intr->enc_status);
+	if (status & 0x00000400) {	/* critical */
+		irq = (status >> 8) & 0x3;
+		if (irq == 2)	/* high priority peripheral */
+			goto peripheral;
+		irq |= (MPC52xx_IRQ_L1_CRIT << MPC52xx_IRQ_L1_OFFSET);
+	} else if (status & 0x00200000) {	/* main */
+		irq = (status >> 16) & 0x1f;
+		if (irq == 4)	/* low priority peripheral */
+			goto peripheral;
+		irq |= (MPC52xx_IRQ_L1_MAIN << MPC52xx_IRQ_L1_OFFSET);
+	} else if (status & 0x20000000) {	/* peripheral */
+	      peripheral:
+		irq = (status >> 24) & 0x1f;
+		if (irq == 0) {	/* bestcomm */
+			status = in_be32(&sdma->IntPend);
+			irq = ffs(status) - 1;
+			irq |= (MPC52xx_IRQ_L1_SDMA << MPC52xx_IRQ_L1_OFFSET);
+		} else {
+			irq |= (MPC52xx_IRQ_L1_PERP << MPC52xx_IRQ_L1_OFFSET);
+		}
+	} else {
+		return NO_IRQ;
+	}
+
+	return irq_linear_revmap(mpc52xx_irqhost, irq);
+}