diff --git a/hw/pci.h b/hw/pci.h
index 738506c..4015d45 100644
--- a/hw/pci.h
+++ b/hw/pci.h
@@ -166,6 +166,7 @@ typedef struct PCIIORegion {
 #define PCI_STATUS_RESERVED2	0x040
 #define PCI_STATUS_FAST_BACK	0x080
 #define PCI_STATUS_DEVSEL_MEDIUM 0x200
+#define PCI_STATUS_DEVSEL_SLOW	0x400
 #define PCI_STATUS_DEVSEL	0x600
 #define  PCI_STATUS_SIG_TARGET_ABORT	0x800 /* Set on target abort */
 #define  PCI_STATUS_REC_MASTER_ABORT	0x2000 /* Set on master abort */