diff --git a/arch/powerpc/platforms/pasemi/setup.c b/arch/powerpc/platforms/pasemi/setup.c
index 6d7d068..b5dfd42 100644
--- a/arch/powerpc/platforms/pasemi/setup.c
+++ b/arch/powerpc/platforms/pasemi/setup.c
@@ -223,7 +223,7 @@
 
 	mpic = mpic_alloc(mpic_node, openpic_addr,
 			  MPIC_PRIMARY|MPIC_LARGE_VECTORS,
-			  0, 0, " PAS-OPIC  ");
+			  0, 0, "PASEMI-OPIC");
 	BUG_ON(!mpic);
 
 	mpic_assign_isu(mpic, 0, openpic_addr + 0x10000);
diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile
index 99a77d7..85cf8c6 100644
--- a/arch/powerpc/sysdev/Makefile
+++ b/arch/powerpc/sysdev/Makefile
@@ -2,7 +2,7 @@
 EXTRA_CFLAGS			+= -mno-minimal-toc
 endif
 
-mpic-msi-obj-$(CONFIG_PCI_MSI)	+= mpic_msi.o mpic_u3msi.o
+mpic-msi-obj-$(CONFIG_PCI_MSI)	+= mpic_msi.o mpic_u3msi.o mpic_pasemi_msi.o
 obj-$(CONFIG_MPIC)		+= mpic.o $(mpic-msi-obj-y)
 
 obj-$(CONFIG_PPC_MPC106)	+= grackle.o
diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index 116173a..f74fe26 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -841,6 +841,24 @@
 	return 0;
 }
 
+void mpic_set_vector(unsigned int virq, unsigned int vector)
+{
+	struct mpic *mpic = mpic_from_irq(virq);
+	unsigned int src = mpic_irq_to_hw(virq);
+	unsigned int vecpri;
+
+	DBG("mpic: set_vector(mpic:@%p,virq:%d,src:%d,vector:0x%x)\n",
+	    mpic, virq, src, vector);
+
+	if (src >= mpic->irq_count)
+		return;
+
+	vecpri = mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI));
+	vecpri = vecpri & ~MPIC_INFO(VECPRI_VECTOR_MASK);
+	vecpri |= vector;
+	mpic_irq_write(src, MPIC_INFO(IRQ_VECTOR_PRI), vecpri);
+}
+
 static struct irq_chip mpic_irq_chip = {
 	.mask		= mpic_mask_irq,
 	.unmask		= mpic_unmask_irq,
@@ -1229,6 +1247,8 @@
 		mpic_u3msi_init(mpic);
 	}
 
+	mpic_pasemi_msi_init(mpic);
+
 	for (i = 0; i < mpic->num_sources; i++) {
 		/* start with vector = source number, and masked */
 		u32 vecpri = MPIC_VECPRI_MASK | i |
diff --git a/arch/powerpc/sysdev/mpic.h b/arch/powerpc/sysdev/mpic.h
index 1cb6bd8..4783c6e 100644
--- a/arch/powerpc/sysdev/mpic.h
+++ b/arch/powerpc/sysdev/mpic.h
@@ -17,6 +17,7 @@
 extern irq_hw_number_t mpic_msi_alloc_hwirqs(struct mpic *mpic, int num);
 extern void mpic_msi_free_hwirqs(struct mpic *mpic, int offset, int num);
 extern int mpic_u3msi_init(struct mpic *mpic);
+extern int mpic_pasemi_msi_init(struct mpic *mpic);
 #else
 static inline void mpic_msi_reserve_hwirq(struct mpic *mpic,
 					  irq_hw_number_t hwirq)
@@ -28,9 +29,15 @@
 {
 	return -1;
 }
+
+static inline int mpic_pasemi_msi_init(struct mpic *mpic)
+{
+	return -1;
+}
 #endif
 
 extern int mpic_set_irq_type(unsigned int virq, unsigned int flow_type);
+extern void mpic_set_vector(unsigned int virq, unsigned int vector);
 extern void mpic_end_irq(unsigned int irq);
 extern void mpic_mask_irq(unsigned int irq);
 extern void mpic_unmask_irq(unsigned int irq);
diff --git a/arch/powerpc/sysdev/mpic_pasemi_msi.c b/arch/powerpc/sysdev/mpic_pasemi_msi.c
new file mode 100644
index 0000000..d6bfda3
--- /dev/null
+++ b/arch/powerpc/sysdev/mpic_pasemi_msi.c
@@ -0,0 +1,172 @@
+/*
+ * Copyright 2007, Olof Johansson, PA Semi
+ *
+ * Based on arch/powerpc/sysdev/mpic_u3msi.c:
+ *
+ * Copyright 2006, Segher Boessenkool, IBM Corporation.
+ * Copyright 2006-2007, Michael Ellerman, IBM Corporation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2 of the
+ * License.
+ *
+ */
+
+#undef DEBUG
+
+#include <linux/irq.h>
+#include <linux/bootmem.h>
+#include <linux/msi.h>
+#include <asm/mpic.h>
+#include <asm/prom.h>
+#include <asm/hw_irq.h>
+#include <asm/ppc-pci.h>
+
+#include "mpic.h"
+
+/* Allocate 16 interrupts per device, to give an alignment of 16,
+ * since that's the size of the grouping w.r.t. affinity. If someone
+ * needs more than 32 MSI's down the road we'll have to rethink this,
+ * but it should be OK for now.
+ */
+#define ALLOC_CHUNK 16
+
+#define PASEMI_MSI_ADDR 0xfc080000
+
+/* A bit ugly, can we get this from the pci_dev somehow? */
+static struct mpic *msi_mpic;
+
+
+static void mpic_pasemi_msi_mask_irq(unsigned int irq)
+{
+	pr_debug("mpic_pasemi_msi_mask_irq %d\n", irq);
+	mask_msi_irq(irq);
+	mpic_mask_irq(irq);
+}
+
+static void mpic_pasemi_msi_unmask_irq(unsigned int irq)
+{
+	pr_debug("mpic_pasemi_msi_unmask_irq %d\n", irq);
+	mpic_unmask_irq(irq);
+	unmask_msi_irq(irq);
+}
+
+static struct irq_chip mpic_pasemi_msi_chip = {
+	.shutdown	= mpic_pasemi_msi_mask_irq,
+	.mask		= mpic_pasemi_msi_mask_irq,
+	.unmask		= mpic_pasemi_msi_unmask_irq,
+	.eoi		= mpic_end_irq,
+	.set_type	= mpic_set_irq_type,
+	.set_affinity	= mpic_set_affinity,
+	.typename	= "PASEMI-MSI ",
+};
+
+static int pasemi_msi_check_device(struct pci_dev *pdev, int nvec, int type)
+{
+	if (type == PCI_CAP_ID_MSIX)
+		pr_debug("pasemi_msi: MSI-X untested, trying anyway\n");
+
+	return 0;
+}
+
+static void pasemi_msi_teardown_msi_irqs(struct pci_dev *pdev)
+{
+	struct msi_desc *entry;
+
+	pr_debug("pasemi_msi_teardown_msi_irqs, pdev %p\n", pdev);
+
+	list_for_each_entry(entry, &pdev->msi_list, list) {
+		if (entry->irq == NO_IRQ)
+			continue;
+
+		set_irq_msi(entry->irq, NULL);
+		mpic_msi_free_hwirqs(msi_mpic, virq_to_hw(entry->irq),
+				     ALLOC_CHUNK);
+		irq_dispose_mapping(entry->irq);
+	}
+
+	return;
+}
+
+static int pasemi_msi_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
+{
+	irq_hw_number_t hwirq;
+	unsigned int virq;
+	struct msi_desc *entry;
+	struct msi_msg msg;
+	u64 addr;
+
+	pr_debug("pasemi_msi_setup_msi_irqs, pdev %p nvec %d type %d\n",
+		 pdev, nvec, type);
+
+	msg.address_hi = 0;
+	msg.address_lo = PASEMI_MSI_ADDR;
+
+	list_for_each_entry(entry, &pdev->msi_list, list) {
+		/* Allocate 16 interrupts for now, since that's the grouping for
+		 * affinity. This can be changed later if it turns out 32 is too
+		 * few MSIs for someone, but restrictions will apply to how the
+		 * sources can be changed independently.
+		 */
+		hwirq = mpic_msi_alloc_hwirqs(msi_mpic, ALLOC_CHUNK);
+		if (hwirq < 0) {
+			pr_debug("pasemi_msi: failed allocating hwirq\n");
+			return hwirq;
+		}
+
+		virq = irq_create_mapping(msi_mpic->irqhost, hwirq);
+		if (virq == NO_IRQ) {
+			pr_debug("pasemi_msi: failed mapping hwirq 0x%lx\n", hwirq);
+			mpic_msi_free_hwirqs(msi_mpic, hwirq, ALLOC_CHUNK);
+			return -ENOSPC;
+		}
+
+		/* Vector on MSI is really an offset, the hardware adds
+		 * it to the value written at the magic address. So set
+		 * it to 0 to remain sane.
+		 */
+		mpic_set_vector(virq, 0);
+
+		set_irq_msi(virq, entry);
+		set_irq_chip(virq, &mpic_pasemi_msi_chip);
+		set_irq_type(virq, IRQ_TYPE_EDGE_RISING);
+
+		pr_debug("pasemi_msi: allocated virq 0x%x (hw 0x%lx) addr 0x%lx\n",
+			  virq, hwirq, addr);
+
+		/* Likewise, the device writes [0...511] into the target
+		 * register to generate MSI [512...1023]
+		 */
+		msg.data = hwirq-0x200;
+		write_msi_msg(virq, &msg);
+	}
+
+	return 0;
+}
+
+int mpic_pasemi_msi_init(struct mpic *mpic)
+{
+	int rc;
+
+	if (!mpic->irqhost->of_node ||
+	    !of_device_is_compatible(mpic->irqhost->of_node,
+				     "pasemi,pwrficient-openpic"))
+		return -ENODEV;
+
+	rc = mpic_msi_init_allocator(mpic);
+	if (rc) {
+		pr_debug("pasemi_msi: Error allocating bitmap!\n");
+		return rc;
+	}
+
+	pr_debug("pasemi_msi: Registering PA Semi MPIC MSI callbacks\n");
+
+	msi_mpic = mpic;
+	WARN_ON(ppc_md.setup_msi_irqs);
+	ppc_md.setup_msi_irqs = pasemi_msi_setup_msi_irqs;
+	ppc_md.teardown_msi_irqs = pasemi_msi_teardown_msi_irqs;
+	ppc_md.msi_check_device = pasemi_msi_check_device;
+
+	return 0;
+}