diff --git a/hw/pci_host.h b/hw/pci_host.h
index 48862b5..92a35f9 100644
--- a/hw/pci_host.h
+++ b/hw/pci_host.h
@@ -25,97 +25,21 @@
 /* Worker routines for a PCI host controller that uses an {address,data}
    register pair to access PCI configuration space.  */
 
-/* debug PCI */
-//#define DEBUG_PCI
+#ifndef PCI_HOST_H
+#define PCI_HOST_H
 
 #include "sysbus.h"
 
-#ifdef DEBUG_PCI
-#define PCI_DPRINTF(fmt, ...) \
-do { printf("pci_host_data: " fmt , ## __VA_ARGS__); } while (0)
-#else
-#define PCI_DPRINTF(fmt, ...)
-#endif
-
 typedef struct {
     SysBusDevice busdev;
     uint32_t config_reg;
     PCIBus *bus;
 } PCIHostState;
 
-static void pci_host_data_writeb(void* opaque, pci_addr_t addr, uint32_t val)
-{
-    PCIHostState *s = opaque;
+/* for mmio */
+int pci_host_data_register_io_memory(PCIHostState *s);
 
-    PCI_DPRINTF("writeb addr " TARGET_FMT_plx " val %x\n",
-                (target_phys_addr_t)addr, val);
-    if (s->config_reg & (1u << 31))
-        pci_data_write(s->bus, s->config_reg | (addr & 3), val, 1);
-}
+/* for ioio */
+void pci_host_data_register_ioport(pio_addr_t ioport, PCIHostState *s);
 
-static void pci_host_data_writew(void* opaque, pci_addr_t addr, uint32_t val)
-{
-    PCIHostState *s = opaque;
-#ifdef TARGET_WORDS_BIGENDIAN
-    val = bswap16(val);
-#endif
-    PCI_DPRINTF("writew addr " TARGET_FMT_plx " val %x\n",
-                (target_phys_addr_t)addr, val);
-    if (s->config_reg & (1u << 31))
-        pci_data_write(s->bus, s->config_reg | (addr & 3), val, 2);
-}
-
-static void pci_host_data_writel(void* opaque, pci_addr_t addr, uint32_t val)
-{
-    PCIHostState *s = opaque;
-#ifdef TARGET_WORDS_BIGENDIAN
-    val = bswap32(val);
-#endif
-    PCI_DPRINTF("writel addr " TARGET_FMT_plx " val %x\n",
-                (target_phys_addr_t)addr, val);
-    if (s->config_reg & (1u << 31))
-        pci_data_write(s->bus, s->config_reg, val, 4);
-}
-
-static uint32_t pci_host_data_readb(void* opaque, pci_addr_t addr)
-{
-    PCIHostState *s = opaque;
-    uint32_t val;
-
-    if (!(s->config_reg & (1 << 31)))
-        return 0xff;
-    val = pci_data_read(s->bus, s->config_reg | (addr & 3), 1);
-    PCI_DPRINTF("readb addr " TARGET_FMT_plx " val %x\n",
-                (target_phys_addr_t)addr, val);
-    return val;
-}
-
-static uint32_t pci_host_data_readw(void* opaque, pci_addr_t addr)
-{
-    PCIHostState *s = opaque;
-    uint32_t val;
-    if (!(s->config_reg & (1 << 31)))
-        return 0xffff;
-    val = pci_data_read(s->bus, s->config_reg | (addr & 3), 2);
-    PCI_DPRINTF("readw addr " TARGET_FMT_plx " val %x\n",
-                (target_phys_addr_t)addr, val);
-#ifdef TARGET_WORDS_BIGENDIAN
-    val = bswap16(val);
-#endif
-    return val;
-}
-
-static uint32_t pci_host_data_readl(void* opaque, pci_addr_t addr)
-{
-    PCIHostState *s = opaque;
-    uint32_t val;
-    if (!(s->config_reg & (1 << 31)))
-        return 0xffffffff;
-    val = pci_data_read(s->bus, s->config_reg | (addr & 3), 4);
-    PCI_DPRINTF("readl addr " TARGET_FMT_plx " val %x\n",
-                (target_phys_addr_t)addr, val);
-#ifdef TARGET_WORDS_BIGENDIAN
-    val = bswap32(val);
-#endif
-    return val;
-}
+#endif /* PCI_HOST_H */