diff --git a/arch/x86/pci/pci.h b/arch/x86/pci/pci.h
index c8b89a8..8ef86b5 100644
--- a/arch/x86/pci/pci.h
+++ b/arch/x86/pci/pci.h
@@ -26,6 +26,7 @@
 #define PCI_ASSIGN_ALL_BUSSES	0x4000
 #define PCI_CAN_SKIP_ISA_ALIGN	0x8000
 #define PCI_USE__CRS		0x10000
+#define PCI_CHECK_ENABLE_AMD_MMCONF	0x20000
 
 extern unsigned int pci_probe;
 extern unsigned long pirq_table_addr;