diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 8757f8d..80e3c17 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -1086,6 +1086,11 @@ static void free_iommu(struct intel_iommu *iommu)
 	iommu_device_destroy(iommu->iommu_dev);
 
 	if (iommu->irq) {
+		if (iommu->pr_irq) {
+			free_irq(iommu->pr_irq, iommu);
+			dmar_free_hwirq(iommu->pr_irq);
+			iommu->pr_irq = 0;
+		}
 		free_irq(iommu->irq, iommu);
 		dmar_free_hwirq(iommu->irq);
 		iommu->irq = 0;
@@ -1493,53 +1498,68 @@ static const char *dmar_get_fault_reason(u8 fault_reason, int *fault_type)
 	}
 }
 
+
+static inline int dmar_msi_reg(struct intel_iommu *iommu, int irq)
+{
+	if (iommu->irq == irq)
+		return DMAR_FECTL_REG;
+	else if (iommu->pr_irq == irq)
+		return DMAR_PECTL_REG;
+	else
+		BUG();
+}
+
 void dmar_msi_unmask(struct irq_data *data)
 {
 	struct intel_iommu *iommu = irq_data_get_irq_handler_data(data);
+	int reg = dmar_msi_reg(iommu, data->irq);
 	unsigned long flag;
 
 	/* unmask it */
 	raw_spin_lock_irqsave(&iommu->register_lock, flag);
-	writel(0, iommu->reg + DMAR_FECTL_REG);
+	writel(0, iommu->reg + reg);
 	/* Read a reg to force flush the post write */
-	readl(iommu->reg + DMAR_FECTL_REG);
+	readl(iommu->reg + reg);
 	raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
 }
 
 void dmar_msi_mask(struct irq_data *data)
 {
-	unsigned long flag;
 	struct intel_iommu *iommu = irq_data_get_irq_handler_data(data);
+	int reg = dmar_msi_reg(iommu, data->irq);
+	unsigned long flag;
 
 	/* mask it */
 	raw_spin_lock_irqsave(&iommu->register_lock, flag);
-	writel(DMA_FECTL_IM, iommu->reg + DMAR_FECTL_REG);
+	writel(DMA_FECTL_IM, iommu->reg + reg);
 	/* Read a reg to force flush the post write */
-	readl(iommu->reg + DMAR_FECTL_REG);
+	readl(iommu->reg + reg);
 	raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
 }
 
 void dmar_msi_write(int irq, struct msi_msg *msg)
 {
 	struct intel_iommu *iommu = irq_get_handler_data(irq);
+	int reg = dmar_msi_reg(iommu, irq);
 	unsigned long flag;
 
 	raw_spin_lock_irqsave(&iommu->register_lock, flag);
-	writel(msg->data, iommu->reg + DMAR_FEDATA_REG);
-	writel(msg->address_lo, iommu->reg + DMAR_FEADDR_REG);
-	writel(msg->address_hi, iommu->reg + DMAR_FEUADDR_REG);
+	writel(msg->data, iommu->reg + reg + 4);
+	writel(msg->address_lo, iommu->reg + reg + 8);
+	writel(msg->address_hi, iommu->reg + reg + 12);
 	raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
 }
 
 void dmar_msi_read(int irq, struct msi_msg *msg)
 {
 	struct intel_iommu *iommu = irq_get_handler_data(irq);
+	int reg = dmar_msi_reg(iommu, irq);
 	unsigned long flag;
 
 	raw_spin_lock_irqsave(&iommu->register_lock, flag);
-	msg->data = readl(iommu->reg + DMAR_FEDATA_REG);
-	msg->address_lo = readl(iommu->reg + DMAR_FEADDR_REG);
-	msg->address_hi = readl(iommu->reg + DMAR_FEUADDR_REG);
+	msg->data = readl(iommu->reg + reg + 4);
+	msg->address_lo = readl(iommu->reg + reg + 8);
+	msg->address_hi = readl(iommu->reg + reg + 12);
 	raw_spin_unlock_irqrestore(&iommu->register_lock, flag);
 }
 
diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index 46add60..f16a2b9 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -60,6 +60,14 @@
 #define DMAR_IQA_REG	0x90	/* Invalidation queue addr register */
 #define DMAR_ICS_REG	0x9c	/* Invalidation complete status register */
 #define DMAR_IRTA_REG	0xb8    /* Interrupt remapping table addr register */
+#define DMAR_PQH_REG	0xc0	/* Page request queue head register */
+#define DMAR_PQT_REG	0xc8	/* Page request queue tail register */
+#define DMAR_PQA_REG	0xd0	/* Page request queue address register */
+#define DMAR_PRS_REG	0xdc	/* Page request status register */
+#define DMAR_PECTL_REG	0xe0	/* Page request event control register */
+#define	DMAR_PEDATA_REG	0xe4	/* Page request event interrupt data register */
+#define	DMAR_PEADDR_REG	0xe8	/* Page request event interrupt addr register */
+#define	DMAR_PEUADDR_REG 0xec	/* Page request event Upper address register */
 
 #define OFFSET_STRIDE		(9)
 
@@ -373,7 +381,7 @@ struct intel_iommu {
 	int		seq_id;	/* sequence id of the iommu */
 	int		agaw; /* agaw of this iommu */
 	int		msagaw; /* max sagaw of this iommu */
-	unsigned int 	irq;
+	unsigned int 	irq, pr_irq;
 	u16		segment;     /* PCI segment# */
 	unsigned char 	name[13];    /* Device Name */
 
