diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 0aeefd2c0d..56ec6cd6c6 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -78,7 +78,6 @@
 #define DPRINTF(fmt, ...)
 #endif
 
-#define BIOS_CFG_IOPORT 0x510
 #define FW_CFG_ACPI_TABLES (FW_CFG_ARCH_LOCAL + 0)
 #define FW_CFG_SMBIOS_ENTRIES (FW_CFG_ARCH_LOCAL + 1)
 #define FW_CFG_IRQ0_OVERRIDE (FW_CFG_ARCH_LOCAL + 2)
@@ -756,7 +755,7 @@ static FWCfgState *bochs_bios_init(AddressSpace *as)
     int i, j;
     unsigned int apic_id_limit = pc_apic_id_limit(max_cpus);
 
-    fw_cfg = fw_cfg_init_io_dma(BIOS_CFG_IOPORT, BIOS_CFG_IOPORT + 4, as);
+    fw_cfg = fw_cfg_init_io_dma(FW_CFG_IO_BASE, FW_CFG_IO_BASE + 4, as);
 
     /* FW_CFG_MAX_CPUS is a bit confusing/problematic on x86:
      *
@@ -1258,7 +1257,7 @@ void xen_load_linux(PCMachineState *pcms)
 
     assert(MACHINE(pcms)->kernel_filename != NULL);
 
-    fw_cfg = fw_cfg_init_io(BIOS_CFG_IOPORT);
+    fw_cfg = fw_cfg_init_io(FW_CFG_IO_BASE);
     rom_set_fw(fw_cfg);
 
     load_linux(pcms, fw_cfg);
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 8b3546ed5c..79ffe5b3ee 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -266,6 +266,8 @@ void ioapic_init_gsi(GSIState *gsi_state, const char *parent_name);
 
 ISADevice *pc_find_fdc0(void);
 
+#define FW_CFG_IO_BASE     0x510
+
 /* acpi_piix.c */
 
 I2CBus *piix4_pm_init(PCIBus *bus, int devfn, uint32_t smb_io_base,