3 files changed, 414 insertions, 236 deletions

diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile
index 054bd8b41ef5..cebfae242602 100644
--- a/arch/powerpc/sysdev/Makefile
+++ b/arch/powerpc/sysdev/Makefile
@@ -4,7 +4,6 @@ endif
 
 obj-$(CONFIG_MPIC)		+= mpic.o
 obj-$(CONFIG_PPC_INDIRECT_PCI)	+= indirect_pci.o
-obj-$(CONFIG_PPC_I8259)		+= i8259.o
 obj-$(CONFIG_PPC_MPC106)	+= grackle.o
 obj-$(CONFIG_BOOKE)		+= dcr.o
 obj-$(CONFIG_40x)		+= dcr.o
@@ -14,3 +13,7 @@ obj-$(CONFIG_PPC_83xx)		+= ipic.o
 obj-$(CONFIG_FSL_SOC)		+= fsl_soc.o
 obj-$(CONFIG_PPC_TODC)		+= todc.o
 obj-$(CONFIG_TSI108_BRIDGE)	+= tsi108_pci.o tsi108_dev.o
+
+ifeq ($(CONFIG_PPC_MERGE),y)
+obj-$(CONFIG_PPC_I8259)		+= i8259.o
+ endif
diff --git a/arch/powerpc/sysdev/i8259.c b/arch/powerpc/sysdev/i8259.c
index 1a3ef1ab9d6e..72c73a6105cd 100644
--- a/arch/powerpc/sysdev/i8259.c
+++ b/arch/powerpc/sysdev/i8259.c
@@ -6,11 +6,16 @@
  * as published by the Free Software Foundation; either version
  * 2 of the License, or (at your option) any later version.
  */
+#undef DEBUG
+
 #include <linux/init.h>
 #include <linux/ioport.h>
 #include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
 #include <asm/io.h>
 #include <asm/i8259.h>
+#include <asm/prom.h>
 
 static volatile void __iomem *pci_intack; /* RO, gives us the irq vector */
 
@@ -20,7 +25,8 @@ static unsigned char cached_8259[2] = { 0xff, 0xff };
 
 static DEFINE_SPINLOCK(i8259_lock);
 
-static int i8259_pic_irq_offset;
+static struct device_node *i8259_node;
+static struct irq_host *i8259_host;
 
 /*
  * Acknowledge the IRQ using either the PCI host bridge's interrupt
@@ -28,16 +34,18 @@ static int i8259_pic_irq_offset;
  * which is called.  It should be noted that polling is broken on some
  * IBM and Motorola PReP boxes so we must use the int-ack feature on them.
  */
-int i8259_irq(struct pt_regs *regs)
+unsigned int i8259_irq(struct pt_regs *regs)
 {
 	int irq;
-
-	spin_lock(&i8259_lock);
+	int lock = 0;
 
 	/* Either int-ack or poll for the IRQ */
 	if (pci_intack)
 		irq = readb(pci_intack);
 	else {
+		spin_lock(&i8259_lock);
+		lock = 1;
+
 		/* Perform an interrupt acknowledge cycle on controller 1. */
 		outb(0x0C, 0x20);		/* prepare for poll */
 		irq = inb(0x20) & 7;
@@ -62,16 +70,13 @@ int i8259_irq(struct pt_regs *regs)
 		if (!pci_intack)
 			outb(0x0B, 0x20);	/* ISR register */
 		if(~inb(0x20) & 0x80)
-			irq = -1;
-	}
+			irq = NO_IRQ;
+	} else if (irq == 0xff)
+		irq = NO_IRQ;
 
-	spin_unlock(&i8259_lock);
-	return irq + i8259_pic_irq_offset;
-}
-
-int i8259_irq_cascade(struct pt_regs *regs, void *unused)
-{
-	return i8259_irq(regs);
+	if (lock)
+		spin_unlock(&i8259_lock);
+	return irq;
 }
 
 static void i8259_mask_and_ack_irq(unsigned int irq_nr)
@@ -79,7 +84,6 @@ static void i8259_mask_and_ack_irq(unsigned int irq_nr)
 	unsigned long flags;
 
 	spin_lock_irqsave(&i8259_lock, flags);
-	irq_nr -= i8259_pic_irq_offset;
 	if (irq_nr > 7) {
 		cached_A1 |= 1 << (irq_nr-8);
 		inb(0xA1); 	/* DUMMY */
@@ -105,8 +109,9 @@ static void i8259_mask_irq(unsigned int irq_nr)
 {
 	unsigned long flags;
 
+	pr_debug("i8259_mask_irq(%d)\n", irq_nr);
+
 	spin_lock_irqsave(&i8259_lock, flags);
-	irq_nr -= i8259_pic_irq_offset;
 	if (irq_nr < 8)
 		cached_21 |= 1 << irq_nr;
 	else
@@ -119,8 +124,9 @@ static void i8259_unmask_irq(unsigned int irq_nr)
 {
 	unsigned long flags;
 
+	pr_debug("i8259_unmask_irq(%d)\n", irq_nr);
+
 	spin_lock_irqsave(&i8259_lock, flags);
-	irq_nr -= i8259_pic_irq_offset;
 	if (irq_nr < 8)
 		cached_21 &= ~(1 << irq_nr);
 	else
@@ -129,19 +135,11 @@ static void i8259_unmask_irq(unsigned int irq_nr)
 	spin_unlock_irqrestore(&i8259_lock, flags);
 }
 
-static void i8259_end_irq(unsigned int irq)
-{
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS))
-	    && irq_desc[irq].action)
-		i8259_unmask_irq(irq);
-}
-
-struct hw_interrupt_type i8259_pic = {
-	.typename = " i8259    ",
-	.enable = i8259_unmask_irq,
-	.disable = i8259_mask_irq,
-	.ack = i8259_mask_and_ack_irq,
-	.end = i8259_end_irq,
+static struct irq_chip i8259_pic = {
+	.typename	= " i8259    ",
+	.mask		= i8259_mask_irq,
+	.unmask		= i8259_unmask_irq,
+	.mask_ack	= i8259_mask_and_ack_irq,
 };
 
 static struct resource pic1_iores = {
@@ -165,25 +163,84 @@ static struct resource pic_edgectrl_iores = {
 	.flags = IORESOURCE_BUSY,
 };
 
-static struct irqaction i8259_irqaction = {
-	.handler = no_action,
-	.flags = IRQF_DISABLED,
-	.mask = CPU_MASK_NONE,
-	.name = "82c59 secondary cascade",
+static int i8259_host_match(struct irq_host *h, struct device_node *node)
+{
+	return i8259_node == NULL || i8259_node == node;
+}
+
+static int i8259_host_map(struct irq_host *h, unsigned int virq,
+			  irq_hw_number_t hw, unsigned int flags)
+{
+	pr_debug("i8259_host_map(%d, 0x%lx)\n", virq, hw);
+
+	/* We block the internal cascade */
+	if (hw == 2)
+		get_irq_desc(virq)->status |= IRQ_NOREQUEST;
+
+	/* We use the level stuff only for now, we might want to
+	 * be more cautious here but that works for now
+	 */
+	get_irq_desc(virq)->status |= IRQ_LEVEL;
+	set_irq_chip_and_handler(virq, &i8259_pic, handle_level_irq);
+	return 0;
+}
+
+static void i8259_host_unmap(struct irq_host *h, unsigned int virq)
+{
+	/* Make sure irq is masked in hardware */
+	i8259_mask_irq(virq);
+
+	/* remove chip and handler */
+	set_irq_chip_and_handler(virq, NULL, NULL);
+
+	/* Make sure it's completed */
+	synchronize_irq(virq);
+}
+
+static int i8259_host_xlate(struct irq_host *h, struct device_node *ct,
+			    u32 *intspec, unsigned int intsize,
+			    irq_hw_number_t *out_hwirq, unsigned int *out_flags)
+{
+	static unsigned char map_isa_senses[4] = {
+		IRQ_TYPE_LEVEL_LOW,
+		IRQ_TYPE_LEVEL_HIGH,
+		IRQ_TYPE_EDGE_FALLING,
+		IRQ_TYPE_EDGE_RISING,
+	};
+
+	*out_hwirq = intspec[0];
+	if (intsize > 1 && intspec[1] < 4)
+		*out_flags = map_isa_senses[intspec[1]];
+	else
+		*out_flags = IRQ_TYPE_NONE;
+
+	return 0;
+}
+
+static struct irq_host_ops i8259_host_ops = {
+	.match = i8259_host_match,
+	.map = i8259_host_map,
+	.unmap = i8259_host_unmap,
+	.xlate = i8259_host_xlate,
 };
 
-/*
- * i8259_init()
- * intack_addr - PCI interrupt acknowledge (real) address which will return
- *               the active irq from the 8259
+/****
+ * i8259_init - Initialize the legacy controller
+ * @node: device node of the legacy PIC (can be NULL, but then, it will match
+ *        all interrupts, so beware)
+ * @intack_addr: PCI interrupt acknowledge (real) address which will return
+ *             	 the active irq from the 8259
  */
-void __init i8259_init(unsigned long intack_addr, int offset)
+void i8259_init(struct device_node *node, unsigned long intack_addr)
 {
 	unsigned long flags;
-	int i;
 
+	/* initialize the controller */
 	spin_lock_irqsave(&i8259_lock, flags);
-	i8259_pic_irq_offset = offset;
+
+	/* Mask all first */
+	outb(0xff, 0xA1);
+	outb(0xff, 0x21);
 
 	/* init master interrupt controller */
 	outb(0x11, 0x20); /* Start init sequence */
@@ -197,21 +254,36 @@ void __init i8259_init(unsigned long intack_addr, int offset)
 	outb(0x02, 0xA1); /* edge triggered, Cascade (slave) on IRQ2 */
 	outb(0x01, 0xA1); /* Select 8086 mode */
 
+	/* That thing is slow */
+	udelay(100);
+
 	/* always read ISR */
 	outb(0x0B, 0x20);
 	outb(0x0B, 0xA0);
 
-	/* Mask all interrupts */
+	/* Unmask the internal cascade */
+	cached_21 &= ~(1 << 2);
+
+	/* Set interrupt masks */
 	outb(cached_A1, 0xA1);
 	outb(cached_21, 0x21);
 
 	spin_unlock_irqrestore(&i8259_lock, flags);
 
-	for (i = 0; i < NUM_ISA_INTERRUPTS; ++i)
-		irq_desc[offset + i].chip = &i8259_pic;
+	/* create a legacy host */
+	if (node)
+		i8259_node = of_node_get(node);
+	i8259_host = irq_alloc_host(IRQ_HOST_MAP_LEGACY, 0, &i8259_host_ops, 0);
+	if (i8259_host == NULL) {
+		printk(KERN_ERR "i8259: failed to allocate irq host !\n");
+		return;
+	}
 
 	/* reserve our resources */
-	setup_irq(offset + 2, &i8259_irqaction);
+	/* XXX should we continue doing that ? it seems to cause problems
+	 * with further requesting of PCI IO resources for that range...
+	 * need to look into it.
+	 */
 	request_resource(&ioport_resource, &pic1_iores);
 	request_resource(&ioport_resource, &pic2_iores);
 	request_resource(&ioport_resource, &pic_edgectrl_iores);
@@ -219,4 +291,5 @@ void __init i8259_init(unsigned long intack_addr, int offset)
 	if (intack_addr != 0)
 		pci_intack = ioremap(intack_addr, 1);
 
+	printk(KERN_INFO "i8259 legacy interrupt controller initialized\n");
 }
diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index 7e469358895f..7d31d7cc392d 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -100,8 +100,8 @@ static inline u32 _mpic_cpu_read(struct mpic *mpic, unsigned int reg)
 
 	if (mpic->flags & MPIC_PRIMARY)
 		cpu = hard_smp_processor_id();
-
-	return _mpic_read(mpic->flags & MPIC_BIG_ENDIAN, mpic->cpuregs[cpu], reg);
+	return _mpic_read(mpic->flags & MPIC_BIG_ENDIAN,
+			  mpic->cpuregs[cpu], reg);
 }
 
 static inline void _mpic_cpu_write(struct mpic *mpic, unsigned int reg, u32 value)
@@ -340,27 +340,19 @@ static void __init mpic_scan_ht_pics(struct mpic *mpic)
 #endif /* CONFIG_MPIC_BROKEN_U3 */
 
 
+#define mpic_irq_to_hw(virq)	((unsigned int)irq_map[virq].hwirq)
+
 /* Find an mpic associated with a given linux interrupt */
 static struct mpic *mpic_find(unsigned int irq, unsigned int *is_ipi)
 {
-	struct mpic *mpic = mpics;
-
-	while(mpic) {
-		/* search IPIs first since they may override the main interrupts */
-		if (irq >= mpic->ipi_offset && irq < (mpic->ipi_offset + 4)) {
-			if (is_ipi)
-				*is_ipi = 1;
-			return mpic;
-		}
-		if (irq >= mpic->irq_offset &&
-		    irq < (mpic->irq_offset + mpic->irq_count)) {
-			if (is_ipi)
-				*is_ipi = 0;
-			return mpic;
-		}
-		mpic = mpic -> next;
-	}
-	return NULL;
+	unsigned int src = mpic_irq_to_hw(irq);
+
+	if (irq < NUM_ISA_INTERRUPTS)
+		return NULL;
+	if (is_ipi)
+		*is_ipi = (src >= MPIC_VEC_IPI_0 && src <= MPIC_VEC_IPI_3);
+
+	return irq_desc[irq].chip_data;
 }
 
 /* Convert a cpu mask from logical to physical cpu numbers. */
@@ -378,14 +370,14 @@ static inline u32 mpic_physmask(u32 cpumask)
 /* Get the mpic structure from the IPI number */
 static inline struct mpic * mpic_from_ipi(unsigned int ipi)
 {
-	return container_of(irq_desc[ipi].chip, struct mpic, hc_ipi);
+	return irq_desc[ipi].chip_data;
 }
 #endif
 
 /* Get the mpic structure from the irq number */
 static inline struct mpic * mpic_from_irq(unsigned int irq)
 {
-	return container_of(irq_desc[irq].chip, struct mpic, hc_irq);
+	return irq_desc[irq].chip_data;
 }
 
 /* Send an EOI */
@@ -398,9 +390,7 @@ static inline void mpic_eoi(struct mpic *mpic)
 #ifdef CONFIG_SMP
 static irqreturn_t mpic_ipi_action(int irq, void *dev_id, struct pt_regs *regs)
 {
-	struct mpic *mpic = dev_id;
-
-	smp_message_recv(irq - mpic->ipi_offset, regs);
+	smp_message_recv(mpic_irq_to_hw(irq) - MPIC_VEC_IPI_0, regs);
 	return IRQ_HANDLED;
 }
 #endif /* CONFIG_SMP */
@@ -410,11 +400,11 @@ static irqreturn_t mpic_ipi_action(int irq, void *dev_id, struct pt_regs *regs)
  */
 
 
-static void mpic_enable_irq(unsigned int irq)
+static void mpic_unmask_irq(unsigned int irq)
 {
 	unsigned int loops = 100000;
 	struct mpic *mpic = mpic_from_irq(irq);
-	unsigned int src = irq - mpic->irq_offset;
+	unsigned int src = mpic_irq_to_hw(irq);
 
 	DBG("%p: %s: enable_irq: %d (src %d)\n", mpic, mpic->name, irq, src);
 
@@ -429,39 +419,13 @@ static void mpic_enable_irq(unsigned int irq)
 			break;
 		}
 	} while(mpic_irq_read(src, MPIC_IRQ_VECTOR_PRI) & MPIC_VECPRI_MASK);	
-
-#ifdef CONFIG_MPIC_BROKEN_U3
-	if (mpic->flags & MPIC_BROKEN_U3) {
-		unsigned int src = irq - mpic->irq_offset;
-		if (mpic_is_ht_interrupt(mpic, src) &&
-		    (irq_desc[irq].status & IRQ_LEVEL))
-			mpic_ht_end_irq(mpic, src);
-	}
-#endif /* CONFIG_MPIC_BROKEN_U3 */
-}
-
-static unsigned int mpic_startup_irq(unsigned int irq)
-{
-#ifdef CONFIG_MPIC_BROKEN_U3
-	struct mpic *mpic = mpic_from_irq(irq);
-	unsigned int src = irq - mpic->irq_offset;
-#endif /* CONFIG_MPIC_BROKEN_U3 */
-
-	mpic_enable_irq(irq);
-
-#ifdef CONFIG_MPIC_BROKEN_U3
-	if (mpic_is_ht_interrupt(mpic, src))
-		mpic_startup_ht_interrupt(mpic, src, irq_desc[irq].status);
-#endif /* CONFIG_MPIC_BROKEN_U3 */
-
-	return 0;
 }
 
-static void mpic_disable_irq(unsigned int irq)
+static void mpic_mask_irq(unsigned int irq)
 {
 	unsigned int loops = 100000;
 	struct mpic *mpic = mpic_from_irq(irq);
-	unsigned int src = irq - mpic->irq_offset;
+	unsigned int src = mpic_irq_to_hw(irq);
 
 	DBG("%s: disable_irq: %d (src %d)\n", mpic->name, irq, src);
 
@@ -478,23 +442,58 @@ static void mpic_disable_irq(unsigned int irq)
 	} while(!(mpic_irq_read(src, MPIC_IRQ_VECTOR_PRI) & MPIC_VECPRI_MASK));
 }
 
-static void mpic_shutdown_irq(unsigned int irq)
+static void mpic_end_irq(unsigned int irq)
 {
+	struct mpic *mpic = mpic_from_irq(irq);
+
+#ifdef DEBUG_IRQ
+	DBG("%s: end_irq: %d\n", mpic->name, irq);
+#endif
+	/* We always EOI on end_irq() even for edge interrupts since that
+	 * should only lower the priority, the MPIC should have properly
+	 * latched another edge interrupt coming in anyway
+	 */
+
+	mpic_eoi(mpic);
+}
+
 #ifdef CONFIG_MPIC_BROKEN_U3
+
+static void mpic_unmask_ht_irq(unsigned int irq)
+{
 	struct mpic *mpic = mpic_from_irq(irq);
-	unsigned int src = irq - mpic->irq_offset;
+	unsigned int src = mpic_irq_to_hw(irq);
 
-	if (mpic_is_ht_interrupt(mpic, src))
-		mpic_shutdown_ht_interrupt(mpic, src, irq_desc[irq].status);
+	mpic_unmask_irq(irq);
 
-#endif /* CONFIG_MPIC_BROKEN_U3 */
+	if (irq_desc[irq].status & IRQ_LEVEL)
+		mpic_ht_end_irq(mpic, src);
+}
+
+static unsigned int mpic_startup_ht_irq(unsigned int irq)
+{
+	struct mpic *mpic = mpic_from_irq(irq);
+	unsigned int src = mpic_irq_to_hw(irq);
+
+	mpic_unmask_irq(irq);
+	mpic_startup_ht_interrupt(mpic, src, irq_desc[irq].status);
 
-	mpic_disable_irq(irq);
+	return 0;
 }
 
-static void mpic_end_irq(unsigned int irq)
+static void mpic_shutdown_ht_irq(unsigned int irq)
 {
 	struct mpic *mpic = mpic_from_irq(irq);
+	unsigned int src = mpic_irq_to_hw(irq);
+
+	mpic_shutdown_ht_interrupt(mpic, src, irq_desc[irq].status);
+	mpic_mask_irq(irq);
+}
+
+static void mpic_end_ht_irq(unsigned int irq)
+{
+	struct mpic *mpic = mpic_from_irq(irq);
+	unsigned int src = mpic_irq_to_hw(irq);
 
 #ifdef DEBUG_IRQ
 	DBG("%s: end_irq: %d\n", mpic->name, irq);
@@ -504,30 +503,25 @@ static void mpic_end_irq(unsigned int irq)
 	 * latched another edge interrupt coming in anyway
 	 */
 
-#ifdef CONFIG_MPIC_BROKEN_U3
-	if (mpic->flags & MPIC_BROKEN_U3) {
-		unsigned int src = irq - mpic->irq_offset;
-		if (mpic_is_ht_interrupt(mpic, src) &&
-		    (irq_desc[irq].status & IRQ_LEVEL))
-			mpic_ht_end_irq(mpic, src);
-	}
-#endif /* CONFIG_MPIC_BROKEN_U3 */
-
+	if (irq_desc[irq].status & IRQ_LEVEL)
+		mpic_ht_end_irq(mpic, src);
 	mpic_eoi(mpic);
 }
 
+#endif /* CONFIG_MPIC_BROKEN_U3 */
+
 #ifdef CONFIG_SMP
 
-static void mpic_enable_ipi(unsigned int irq)
+static void mpic_unmask_ipi(unsigned int irq)
 {
 	struct mpic *mpic = mpic_from_ipi(irq);
-	unsigned int src = irq - mpic->ipi_offset;
+	unsigned int src = mpic_irq_to_hw(irq) - MPIC_VEC_IPI_0;
 
 	DBG("%s: enable_ipi: %d (ipi %d)\n", mpic->name, irq, src);
 	mpic_ipi_write(src, mpic_ipi_read(src) & ~MPIC_VECPRI_MASK);
 }
 
-static void mpic_disable_ipi(unsigned int irq)
+static void mpic_mask_ipi(unsigned int irq)
 {
 	/* NEVER disable an IPI... that's just plain wrong! */
 }
@@ -551,29 +545,176 @@ static void mpic_end_ipi(unsigned int irq)
 static void mpic_set_affinity(unsigned int irq, cpumask_t cpumask)
 {
 	struct mpic *mpic = mpic_from_irq(irq);
+	unsigned int src = mpic_irq_to_hw(irq);
 
 	cpumask_t tmp;
 
 	cpus_and(tmp, cpumask, cpu_online_map);
 
-	mpic_irq_write(irq - mpic->irq_offset, MPIC_IRQ_DESTINATION,
+	mpic_irq_write(src, MPIC_IRQ_DESTINATION,
 		       mpic_physmask(cpus_addr(tmp)[0]));	
 }
 
+static unsigned int mpic_flags_to_vecpri(unsigned int flags, int *level)
+{
+	unsigned int vecpri;
+
+	/* Now convert sense value */
+	switch(flags & IRQ_TYPE_SENSE_MASK) {
+	case IRQ_TYPE_EDGE_RISING:
+		vecpri = MPIC_VECPRI_SENSE_EDGE |
+			MPIC_VECPRI_POLARITY_POSITIVE;
+		*level = 0;
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		vecpri = MPIC_VECPRI_SENSE_EDGE |
+			MPIC_VECPRI_POLARITY_NEGATIVE;
+		*level = 0;
+		break;
+	case IRQ_TYPE_LEVEL_HIGH:
+		vecpri = MPIC_VECPRI_SENSE_LEVEL |
+			MPIC_VECPRI_POLARITY_POSITIVE;
+		*level = 1;
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+	default:
+		vecpri = MPIC_VECPRI_SENSE_LEVEL |
+			MPIC_VECPRI_POLARITY_NEGATIVE;
+		*level = 1;
+	}
+	return vecpri;
+}
+
+static struct irq_chip mpic_irq_chip = {
+	.mask	= mpic_mask_irq,
+	.unmask	= mpic_unmask_irq,
+	.eoi	= mpic_end_irq,
+};
+
+#ifdef CONFIG_SMP
+static struct irq_chip mpic_ipi_chip = {
+	.mask	= mpic_mask_ipi,
+	.unmask	= mpic_unmask_ipi,
+	.eoi	= mpic_end_ipi,
+};
+#endif /* CONFIG_SMP */
+
+#ifdef CONFIG_MPIC_BROKEN_U3
+static struct irq_chip mpic_irq_ht_chip = {
+	.startup	= mpic_startup_ht_irq,
+	.shutdown	= mpic_shutdown_ht_irq,
+	.mask		= mpic_mask_irq,
+	.unmask		= mpic_unmask_ht_irq,
+	.eoi		= mpic_end_ht_irq,
+};
+#endif /* CONFIG_MPIC_BROKEN_U3 */
+
+
+static int mpic_host_match(struct irq_host *h, struct device_node *node)
+{
+	struct mpic *mpic = h->host_data;
+
+	/* Exact match, unless mpic node is NULL */
+	return mpic->of_node == NULL || mpic->of_node == node;
+}
+
+static int mpic_host_map(struct irq_host *h, unsigned int virq,
+			 irq_hw_number_t hw, unsigned int flags)
+{
+	struct irq_desc *desc = get_irq_desc(virq);
+	struct irq_chip *chip;
+	struct mpic *mpic = h->host_data;
+	unsigned int vecpri = MPIC_VECPRI_SENSE_LEVEL |
+		MPIC_VECPRI_POLARITY_NEGATIVE;
+	int level;
+
+	pr_debug("mpic: map virq %d, hwirq 0x%lx, flags: 0x%x\n",
+		 virq, hw, flags);
+
+	if (hw == MPIC_VEC_SPURRIOUS)
+		return -EINVAL;
+#ifdef CONFIG_SMP
+	else if (hw >= MPIC_VEC_IPI_0) {
+		WARN_ON(!(mpic->flags & MPIC_PRIMARY));
+
+		pr_debug("mpic: mapping as IPI\n");
+		set_irq_chip_data(virq, mpic);
+		set_irq_chip_and_handler(virq, &mpic->hc_ipi,
+					 handle_percpu_irq);
+		return 0;
+	}
+#endif /* CONFIG_SMP */
+
+	if (hw >= mpic->irq_count)
+		return -EINVAL;
+
+	/* If no sense provided, check default sense array */
+	if (((flags & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_NONE) &&
+	    mpic->senses && hw < mpic->senses_count)
+		flags |= mpic->senses[hw];
+
+	vecpri = mpic_flags_to_vecpri(flags, &level);
+	if (level)
+		desc->status |= IRQ_LEVEL;
+	chip = &mpic->hc_irq;
+
+#ifdef CONFIG_MPIC_BROKEN_U3
+	/* Check for HT interrupts, override vecpri */
+	if (mpic_is_ht_interrupt(mpic, hw)) {
+		vecpri &= ~(MPIC_VECPRI_SENSE_MASK |
+			    MPIC_VECPRI_POLARITY_MASK);
+		vecpri |= MPIC_VECPRI_POLARITY_POSITIVE;
+		chip = &mpic->hc_ht_irq;
+	}
+#endif
+
+	/* Reconfigure irq */
+	vecpri |= MPIC_VECPRI_MASK | hw | (8 << MPIC_VECPRI_PRIORITY_SHIFT);
+	mpic_irq_write(hw, MPIC_IRQ_VECTOR_PRI, vecpri);
+
+	pr_debug("mpic: mapping as IRQ\n");
+
+	set_irq_chip_data(virq, mpic);
+	set_irq_chip_and_handler(virq, chip, handle_fasteoi_irq);
+	return 0;
+}
+
+static int mpic_host_xlate(struct irq_host *h, struct device_node *ct,
+			   u32 *intspec, unsigned int intsize,
+			   irq_hw_number_t *out_hwirq, unsigned int *out_flags)
+
+{
+	static unsigned char map_mpic_senses[4] = {
+		IRQ_TYPE_EDGE_RISING,
+		IRQ_TYPE_LEVEL_LOW,
+		IRQ_TYPE_LEVEL_HIGH,
+		IRQ_TYPE_EDGE_FALLING,
+	};
+
+	*out_hwirq = intspec[0];
+	if (intsize > 1 && intspec[1] < 4)
+		*out_flags = map_mpic_senses[intspec[1]];
+	else
+		*out_flags = IRQ_TYPE_NONE;
+
+	return 0;
+}
+
+static struct irq_host_ops mpic_host_ops = {
+	.match = mpic_host_match,
+	.map = mpic_host_map,
+	.xlate = mpic_host_xlate,
+};
 
 /*
  * Exported functions
  */
 
-
-struct mpic * __init mpic_alloc(unsigned long phys_addr,
+struct mpic * __init mpic_alloc(struct device_node *node,
+				unsigned long phys_addr,
 				unsigned int flags,
 				unsigned int isu_size,
-				unsigned int irq_offset,
 				unsigned int irq_count,
-				unsigned int ipi_offset,
-				unsigned char *senses,
-				unsigned int senses_count,
 				const char *name)
 {
 	struct mpic	*mpic;
@@ -585,33 +726,38 @@ struct mpic * __init mpic_alloc(unsigned long phys_addr,
 	if (mpic == NULL)
 		return NULL;
 	
-
 	memset(mpic, 0, sizeof(struct mpic));
 	mpic->name = name;
+	mpic->of_node = node ? of_node_get(node) : NULL;
 
+	mpic->irqhost = irq_alloc_host(IRQ_HOST_MAP_LINEAR, 256,
+				       &mpic_host_ops,
+				       MPIC_VEC_SPURRIOUS);
+	if (mpic->irqhost == NULL) {
+		of_node_put(node);
+		return NULL;
+	}
+
+	mpic->irqhost->host_data = mpic;
+	mpic->hc_irq = mpic_irq_chip;
 	mpic->hc_irq.typename = name;
-	mpic->hc_irq.startup = mpic_startup_irq;
-	mpic->hc_irq.shutdown = mpic_shutdown_irq;
-	mpic->hc_irq.enable = mpic_enable_irq;
-	mpic->hc_irq.disable = mpic_disable_irq;
-	mpic->hc_irq.end = mpic_end_irq;
 	if (flags & MPIC_PRIMARY)
 		mpic->hc_irq.set_affinity = mpic_set_affinity;
+#ifdef CONFIG_MPIC_BROKEN_U3
+	mpic->hc_ht_irq = mpic_irq_ht_chip;
+	mpic->hc_ht_irq.typename = name;
+	if (flags & MPIC_PRIMARY)
+		mpic->hc_ht_irq.set_affinity = mpic_set_affinity;
+#endif /* CONFIG_MPIC_BROKEN_U3 */
 #ifdef CONFIG_SMP
+	mpic->hc_ipi = mpic_ipi_chip;
 	mpic->hc_ipi.typename = name;
-	mpic->hc_ipi.enable = mpic_enable_ipi;
-	mpic->hc_ipi.disable = mpic_disable_ipi;
-	mpic->hc_ipi.end = mpic_end_ipi;
 #endif /* CONFIG_SMP */
 
 	mpic->flags = flags;
 	mpic->isu_size = isu_size;
-	mpic->irq_offset = irq_offset;
 	mpic->irq_count = irq_count;
-	mpic->ipi_offset = ipi_offset;
 	mpic->num_sources = 0; /* so far */
-	mpic->senses = senses;
-	mpic->senses_count = senses_count;
 
 	/* Map the global registers */
 	mpic->gregs = ioremap(phys_addr + MPIC_GREG_BASE, 0x1000);
@@ -679,8 +825,10 @@ struct mpic * __init mpic_alloc(unsigned long phys_addr,
 	mpic->next = mpics;
 	mpics = mpic;
 
-	if (flags & MPIC_PRIMARY)
+	if (flags & MPIC_PRIMARY) {
 		mpic_primary = mpic;
+		irq_set_default_host(mpic->irqhost);
+	}
 
 	return mpic;
 }
@@ -697,26 +845,10 @@ void __init mpic_assign_isu(struct mpic *mpic, unsigned int isu_num,
 		mpic->num_sources = isu_first + mpic->isu_size;
 }
 
-void __init mpic_setup_cascade(unsigned int irq, mpic_cascade_t handler,
-			       void *data)
+void __init mpic_set_default_senses(struct mpic *mpic, u8 *senses, int count)
 {
-	struct mpic *mpic = mpic_find(irq, NULL);
-	unsigned long flags;
-
-	/* Synchronization here is a bit dodgy, so don't try to replace cascade
-	 * interrupts on the fly too often ... but normally it's set up at boot.
-	 */
-	spin_lock_irqsave(&mpic_lock, flags);
-	if (mpic->cascade)	       
-		mpic_disable_irq(mpic->cascade_vec + mpic->irq_offset);
-	mpic->cascade = NULL;
-	wmb();
-	mpic->cascade_vec = irq - mpic->irq_offset;
-	mpic->cascade_data = data;
-	wmb();
-	mpic->cascade = handler;
-	mpic_enable_irq(irq);
-	spin_unlock_irqrestore(&mpic_lock, flags);
+	mpic->senses = senses;
+	mpic->senses_count = count;
 }
 
 void __init mpic_init(struct mpic *mpic)
@@ -724,6 +856,11 @@ void __init mpic_init(struct mpic *mpic)
 	int i;
 
 	BUG_ON(mpic->num_sources == 0);
+	WARN_ON(mpic->num_sources > MPIC_VEC_IPI_0);
+
+	/* Sanitize source count */
+	if (mpic->num_sources > MPIC_VEC_IPI_0)
+		mpic->num_sources = MPIC_VEC_IPI_0;
 
 	printk(KERN_INFO "mpic: Initializing for %d sources\n", mpic->num_sources);
 
@@ -747,12 +884,6 @@ void __init mpic_init(struct mpic *mpic)
 			       MPIC_VECPRI_MASK |
 			       (10 << MPIC_VECPRI_PRIORITY_SHIFT) |
 			       (MPIC_VEC_IPI_0 + i));
-#ifdef CONFIG_SMP
-		if (!(mpic->flags & MPIC_PRIMARY))
-			continue;
-		irq_desc[mpic->ipi_offset+i].status |= IRQ_PER_CPU;
-		irq_desc[mpic->ipi_offset+i].chip = &mpic->hc_ipi;
-#endif /* CONFIG_SMP */
 	}
 
 	/* Initialize interrupt sources */
@@ -763,31 +894,21 @@ void __init mpic_init(struct mpic *mpic)
 	/* Do the HT PIC fixups on U3 broken mpic */
 	DBG("MPIC flags: %x\n", mpic->flags);
 	if ((mpic->flags & MPIC_BROKEN_U3) && (mpic->flags & MPIC_PRIMARY))
-		mpic_scan_ht_pics(mpic);
+ 		mpic_scan_ht_pics(mpic);
 #endif /* CONFIG_MPIC_BROKEN_U3 */
 
 	for (i = 0; i < mpic->num_sources; i++) {
 		/* start with vector = source number, and masked */
 		u32 vecpri = MPIC_VECPRI_MASK | i | (8 << MPIC_VECPRI_PRIORITY_SHIFT);
-		int level = 0;
+		int level = 1;
 		
-		/* if it's an IPI, we skip it */
-		if ((mpic->irq_offset + i) >= (mpic->ipi_offset + i) &&
-		    (mpic->irq_offset + i) <  (mpic->ipi_offset + i + 4))
-			continue;
-
 		/* do senses munging */
-		if (mpic->senses && i < mpic->senses_count) {
-			if (mpic->senses[i] & IRQ_SENSE_LEVEL)
-				vecpri |= MPIC_VECPRI_SENSE_LEVEL;
-			if (mpic->senses[i] & IRQ_POLARITY_POSITIVE)
-				vecpri |= MPIC_VECPRI_POLARITY_POSITIVE;
-		} else
+		if (mpic->senses && i < mpic->senses_count)
+			vecpri = mpic_flags_to_vecpri(mpic->senses[i],
+						      &level);
+		else
 			vecpri |= MPIC_VECPRI_SENSE_LEVEL;
 
-		/* remember if it was a level interrupts */
-		level = (vecpri & MPIC_VECPRI_SENSE_LEVEL);
-
 		/* deal with broken U3 */
 		if (mpic->flags & MPIC_BROKEN_U3) {
 #ifdef CONFIG_MPIC_BROKEN_U3
@@ -808,12 +929,6 @@ void __init mpic_init(struct mpic *mpic)
 		mpic_irq_write(i, MPIC_IRQ_VECTOR_PRI, vecpri);
 		mpic_irq_write(i, MPIC_IRQ_DESTINATION,
 			       1 << hard_smp_processor_id());
-
-		/* init linux descriptors */
-		if (i < mpic->irq_count) {
-			irq_desc[mpic->irq_offset+i].status = level ? IRQ_LEVEL : 0;
-			irq_desc[mpic->irq_offset+i].chip = &mpic->hc_irq;
-		}
 	}
 	
 	/* Init spurrious vector */
@@ -854,19 +969,20 @@ void mpic_irq_set_priority(unsigned int irq, unsigned int pri)
 {
 	int is_ipi;
 	struct mpic *mpic = mpic_find(irq, &is_ipi);
+	unsigned int src = mpic_irq_to_hw(irq);
 	unsigned long flags;
 	u32 reg;
 
 	spin_lock_irqsave(&mpic_lock, flags);
 	if (is_ipi) {
-		reg = mpic_ipi_read(irq - mpic->ipi_offset) &
+		reg = mpic_ipi_read(src - MPIC_VEC_IPI_0) &
 			~MPIC_VECPRI_PRIORITY_MASK;
-		mpic_ipi_write(irq - mpic->ipi_offset,
+		mpic_ipi_write(src - MPIC_VEC_IPI_0,
 			       reg | (pri << MPIC_VECPRI_PRIORITY_SHIFT));
 	} else {
-		reg = mpic_irq_read(irq - mpic->irq_offset,MPIC_IRQ_VECTOR_PRI)
+		reg = mpic_irq_read(src, MPIC_IRQ_VECTOR_PRI)
 			& ~MPIC_VECPRI_PRIORITY_MASK;
-		mpic_irq_write(irq - mpic->irq_offset, MPIC_IRQ_VECTOR_PRI,
+		mpic_irq_write(src, MPIC_IRQ_VECTOR_PRI,
 			       reg | (pri << MPIC_VECPRI_PRIORITY_SHIFT));
 	}
 	spin_unlock_irqrestore(&mpic_lock, flags);
@@ -876,14 +992,15 @@ unsigned int mpic_irq_get_priority(unsigned int irq)
 {
 	int is_ipi;
 	struct mpic *mpic = mpic_find(irq, &is_ipi);
+	unsigned int src = mpic_irq_to_hw(irq);
 	unsigned long flags;
 	u32 reg;
 
 	spin_lock_irqsave(&mpic_lock, flags);
 	if (is_ipi)
-		reg = mpic_ipi_read(irq - mpic->ipi_offset);
+		reg = mpic_ipi_read(src = MPIC_VEC_IPI_0);
 	else
-		reg = mpic_irq_read(irq - mpic->irq_offset, MPIC_IRQ_VECTOR_PRI);
+		reg = mpic_irq_read(src, MPIC_IRQ_VECTOR_PRI);
 	spin_unlock_irqrestore(&mpic_lock, flags);
 	return (reg & MPIC_VECPRI_PRIORITY_MASK) >> MPIC_VECPRI_PRIORITY_SHIFT;
 }
@@ -978,37 +1095,20 @@ void mpic_send_ipi(unsigned int ipi_no, unsigned int cpu_mask)
 		       mpic_physmask(cpu_mask & cpus_addr(cpu_online_map)[0]));
 }
 
-int mpic_get_one_irq(struct mpic *mpic, struct pt_regs *regs)
+unsigned int mpic_get_one_irq(struct mpic *mpic, struct pt_regs *regs)
 {
-	u32 irq;
+	u32 src;
 
-	irq = mpic_cpu_read(MPIC_CPU_INTACK) & MPIC_VECPRI_VECTOR_MASK;
+	src = mpic_cpu_read(MPIC_CPU_INTACK) & MPIC_VECPRI_VECTOR_MASK;
 #ifdef DEBUG_LOW
-	DBG("%s: get_one_irq(): %d\n", mpic->name, irq);
+	DBG("%s: get_one_irq(): %d\n", mpic->name, src);
 #endif
-	if (mpic->cascade && irq == mpic->cascade_vec) {
-#ifdef DEBUG_LOW
-		DBG("%s: cascading ...\n", mpic->name);
-#endif
-		irq = mpic->cascade(regs, mpic->cascade_data);
-		mpic_eoi(mpic);
-		return irq;
-	}
-	if (unlikely(irq == MPIC_VEC_SPURRIOUS))
-		return -1;
-	if (irq < MPIC_VEC_IPI_0) {
-#ifdef DEBUG_IRQ
-		DBG("%s: irq %d\n", mpic->name, irq + mpic->irq_offset);
-#endif
-		return irq + mpic->irq_offset;
-	}
-#ifdef DEBUG_IPI
-       	DBG("%s: ipi %d !\n", mpic->name, irq - MPIC_VEC_IPI_0);
-#endif
-	return irq - MPIC_VEC_IPI_0 + mpic->ipi_offset;
+	if (unlikely(src == MPIC_VEC_SPURRIOUS))
+		return NO_IRQ;
+	return irq_linear_revmap(mpic->irqhost, src);
 }
 
-int mpic_get_irq(struct pt_regs *regs)
+unsigned int mpic_get_irq(struct pt_regs *regs)
 {
 	struct mpic *mpic = mpic_primary;
 
@@ -1022,25 +1122,27 @@ int mpic_get_irq(struct pt_regs *regs)
 void mpic_request_ipis(void)
 {
 	struct mpic *mpic = mpic_primary;
-
+	int i;
+	static char *ipi_names[] = {
+		"IPI0 (call function)",
+		"IPI1 (reschedule)",
+		"IPI2 (unused)",
+		"IPI3 (debugger break)",
+	};
 	BUG_ON(mpic == NULL);
-	
-	printk("requesting IPIs ... \n");
 
-	/*
-	 * IPIs are marked IRQF_DISABLED as they must run with irqs
-	 * disabled
-	 */
-	request_irq(mpic->ipi_offset+0, mpic_ipi_action, IRQF_DISABLED,
-		    "IPI0 (call function)", mpic);
-	request_irq(mpic->ipi_offset+1, mpic_ipi_action, IRQF_DISABLED,
-		   "IPI1 (reschedule)", mpic);
-	request_irq(mpic->ipi_offset+2, mpic_ipi_action, IRQF_DISABLED,
-		   "IPI2 (unused)", mpic);
-	request_irq(mpic->ipi_offset+3, mpic_ipi_action, IRQF_DISABLED,
-		   "IPI3 (debugger break)", mpic);
-
-	printk("IPIs requested... \n");
+	printk(KERN_INFO "mpic: requesting IPIs ... \n");
+
+	for (i = 0; i < 4; i++) {
+		unsigned int vipi = irq_create_mapping(mpic->irqhost,
+						       MPIC_VEC_IPI_0 + i, 0);
+		if (vipi == NO_IRQ) {
+			printk(KERN_ERR "Failed to map IPI %d\n", i);
+			break;
+		}
+		request_irq(vipi, mpic_ipi_action, IRQF_DISABLED,
+			    ipi_names[i], mpic);
+	}
 }
 
 void smp_mpic_message_pass(int target, int msg)