[POWERPC] Add new interrupt mapping core and change platforms to use it

This adds the new irq remapper core and removes the old one.  Because
there are some fundamental conflicts with the old code, like the value
of NO_IRQ which I'm now setting to 0 (as per discussions with Linus),
etc..., this commit also changes the relevant platform and driver code
over to use the new remapper (so as not to cause difficulties later
in bisecting).

This patch removes the old pre-parsing of the open firmware interrupt
tree along with all the bogus assumptions it made to try to renumber
interrupts according to the platform. This is all to be handled by the
new code now.

For the pSeries XICS interrupt controller, a single remapper host is
created for the whole machine regardless of how many interrupt
presentation and source controllers are found, and it's set to match
any device node that isn't a 8259.  That works fine on pSeries and
avoids having to deal with some of the complexities of split source
controllers vs. presentation controllers in the pSeries device trees.

The powerpc i8259 PIC driver now always requests the legacy interrupt
range. It also has the feature of being able to match any device node
(including NULL) if passed no device node as an input. That will help
porting over platforms with broken device-trees like Pegasos who don't
have a proper interrupt tree.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

2 files changed, 325 insertions, 149 deletions

diff --git a/arch/powerpc/sysdev/i8259.c b/arch/powerpc/sysdev/i8259.c
index c2e9465871aa..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;
@@ -62,11 +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;
+        if (lock)
+                spin_unlock(&i8259_lock);
+        return irq;
 }
 
 static void i8259_mask_and_ack_irq(unsigned int irq_nr)
@@ -74,7 +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 */
@@ -100,8 +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
@@ -114,8 +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
@@ -152,25 +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 */
@@ -184,24 +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) {
-                set_irq_chip_and_handler(offset + i, &i8259_pic,
-                                         handle_level_irq);
-                irq_desc[offset + i].status |= IRQ_LEVEL;
+        /* 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);
@@ -209,4 +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 9a95f16c19a5..7d31d7cc392d 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -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. */
@@ -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 */
@@ -414,7 +404,7 @@ 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);
 
@@ -435,7 +425,7 @@ 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);
 
@@ -472,7 +462,7 @@ static void mpic_end_irq(unsigned int irq)
 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);
 
         mpic_unmask_irq(irq);
 
@@ -483,7 +473,7 @@ static void mpic_unmask_ht_irq(unsigned int irq)
 static unsigned int mpic_startup_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);
 
         mpic_unmask_irq(irq);
         mpic_startup_ht_interrupt(mpic, src, irq_desc[irq].status);
@@ -494,7 +484,7 @@ static unsigned int mpic_startup_ht_irq(unsigned int irq)
 static void mpic_shutdown_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);
 
         mpic_shutdown_ht_interrupt(mpic, src, irq_desc[irq].status);
         mpic_mask_irq(irq);
@@ -503,7 +493,7 @@ static void mpic_shutdown_ht_irq(unsigned int irq)
 static void mpic_end_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);
 
 #ifdef DEBUG_IRQ
         DBG("%s: end_irq: %d\n", mpic->name, irq);
@@ -525,7 +515,7 @@ static void mpic_end_ht_irq(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);
@@ -555,15 +545,46 @@ 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,
@@ -589,19 +610,111 @@ static struct irq_chip mpic_irq_ht_chip = {
 #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;
@@ -613,10 +726,19 @@ 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;
         if (flags & MPIC_PRIMARY)
@@ -628,18 +750,14 @@ struct mpic * __init mpic_alloc(unsigned long phys_addr,
                 mpic->hc_ht_irq.set_affinity = mpic_set_affinity;
 #endif /* CONFIG_MPIC_BROKEN_U3 */
 #ifdef CONFIG_SMP
-        mpic->hc_ipi.typename = name;
         mpic->hc_ipi = mpic_ipi_chip;
+        mpic->hc_ipi.typename = name;
 #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);
@@ -707,8 +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;
 }
@@ -725,11 +845,22 @@ void __init mpic_assign_isu(struct mpic *mpic, unsigned int isu_num,
                 mpic->num_sources = isu_first + mpic->isu_size;
 }
 
+void __init mpic_set_default_senses(struct mpic *mpic, u8 *senses, int count)
+{
+        mpic->senses = senses;
+        mpic->senses_count = count;
+}
+
 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);
 
@@ -753,14 +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;
-                set_irq_chip_data(mpic->ipi_offset+i, mpic);
-                set_irq_chip_and_handler(mpic->ipi_offset+i,
-                                         &mpic->hc_ipi,
-                                         handle_percpu_irq);
-#endif /* CONFIG_SMP */
         }
 
         /* Initialize interrupt sources */
@@ -777,25 +900,15 @@ void __init mpic_init(struct mpic *mpic)
         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
@@ -816,21 +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) {
-                        struct irq_chip *chip = &mpic->hc_irq;
-
-                        irq_desc[mpic->irq_offset+i].status |=
-                                level ? IRQ_LEVEL : 0;
-#ifdef CONFIG_MPIC_BROKEN_U3
-                        if (mpic_is_ht_interrupt(mpic, i))
-                                chip = &mpic->hc_ht_irq;
-#endif /* CONFIG_MPIC_BROKEN_U3 */
-                        set_irq_chip_data(mpic->irq_offset+i, mpic);
-                        set_irq_chip_and_handler(mpic->irq_offset+i, chip,
-                                                 handle_fasteoi_irq);
-                }
         }
         
         /* Init spurrious vector */
@@ -871,19 +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);
@@ -893,14 +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;
 }
@@ -995,29 +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);
-#endif
-        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);
+        DBG("%s: get_one_irq(): %d\n", mpic->name, src);
 #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;
 
@@ -1031,25 +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)