diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 3627732..7ffac27 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -381,7 +381,7 @@
 	entry->msi_attrib.default_irq = dev->irq;	/* Save IOAPIC IRQ */
 	entry->msi_attrib.pos = pos;
 
-	entry->mask_pos = msi_mask_bits_reg(pos, entry->msi_attrib.is_64);
+	entry->mask_pos = msi_mask_reg(pos, entry->msi_attrib.is_64);
 	/* All MSIs are unmasked by default, Mask them all */
 	if (entry->msi_attrib.maskbit)
 		pci_read_config_dword(dev, entry->mask_pos, &entry->masked);
diff --git a/drivers/pci/msi.h b/drivers/pci/msi.h
index 4fed592..a066284 100644
--- a/drivers/pci/msi.h
+++ b/drivers/pci/msi.h
@@ -16,9 +16,9 @@
 #define msi_lower_address_reg(base)	(base + PCI_MSI_ADDRESS_LO)
 #define msi_upper_address_reg(base)	(base + PCI_MSI_ADDRESS_HI)
 #define msi_data_reg(base, is64bit)	\
-	( (is64bit == 1) ? base+PCI_MSI_DATA_64 : base+PCI_MSI_DATA_32 )
-#define msi_mask_bits_reg(base, is64bit) \
-	( (is64bit == 1) ? base+PCI_MSI_MASK_BIT : base+PCI_MSI_MASK_BIT-4)
+	(base + ((is64bit == 1) ? PCI_MSI_DATA_64 : PCI_MSI_DATA_32))
+#define msi_mask_reg(base, is64bit)	\
+	(base + ((is64bit == 1) ? PCI_MSI_MASK_64 : PCI_MSI_MASK_32))
 #define is_64bit_address(control)	(!!(control & PCI_MSI_FLAGS_64BIT))
 #define is_mask_bit_support(control)	(!!(control & PCI_MSI_FLAGS_MASKBIT))