diff --git a/src/arch/x86/include/arch/pci_io_cfg.h b/src/arch/x86/include/arch/pci_io_cfg.h
index 45c757c95b..288bbc2eff 100644
--- a/src/arch/x86/include/arch/pci_io_cfg.h
+++ b/src/arch/x86/include/arch/pci_io_cfg.h
@@ -7,8 +7,10 @@
 #include <arch/io.h>
 #include <device/pci_type.h>
 
-#define PCI_IO_CONFIG_INDEX	0xcf8
-#define PCI_IO_CONFIG_DATA	0xcfc
+#define PCI_IO_CONFIG_INDEX		0xcf8
+#define PCI_IO_CONFIG_DATA		0xcfc
+#define PCI_IO_CONFIG_PORT_COUNT	8
+#define PCI_IO_CONFIG_LAST_PORT		(PCI_IO_CONFIG_INDEX + PCI_IO_CONFIG_PORT_COUNT - 1)
 
 static __always_inline
 uint32_t pci_io_encode_addr(pci_devfn_t dev, uint16_t reg)