diff --git a/hw/net/cadence_gem.c b/hw/net/cadence_gem.c
index 5994306..dafe914 100644
--- a/hw/net/cadence_gem.c
+++ b/hw/net/cadence_gem.c
@@ -24,8 +24,7 @@
 
 #include <zlib.h> /* For crc32 */
 
-#include "hw/sysbus.h"
-#include "net/net.h"
+#include "hw/net/cadence_gem.h"
 #include "net/checksum.h"
 
 #ifdef CADENCE_GEM_ERR_DEBUG
@@ -141,8 +140,6 @@
 #define GEM_DESCONF6      (0x00000294/4)
 #define GEM_DESCONF7      (0x00000298/4)
 
-#define CADENCE_GEM_MAXREG        (0x00000640/4) /* Last valid GEM address */
-
 /*****************************************/
 #define GEM_NWCTRL_TXSTART     0x00000200 /* Transmit Enable */
 #define GEM_NWCTRL_TXENA       0x00000008 /* Transmit Enable */
@@ -349,44 +346,6 @@ static inline void rx_desc_set_sar(unsigned *desc, int sar_idx)
     desc[1] |= R_DESC_1_RX_SAR_MATCH;
 }
 
-#define TYPE_CADENCE_GEM "cadence_gem"
-#define CADENCE_GEM(obj) OBJECT_CHECK(CadenceGEMState, (obj), TYPE_CADENCE_GEM)
-
-typedef struct CadenceGEMState {
-    SysBusDevice parent_obj;
-
-    MemoryRegion iomem;
-    NICState *nic;
-    NICConf conf;
-    qemu_irq irq;
-
-    /* GEM registers backing store */
-    uint32_t regs[CADENCE_GEM_MAXREG];
-    /* Mask of register bits which are write only */
-    uint32_t regs_wo[CADENCE_GEM_MAXREG];
-    /* Mask of register bits which are read only */
-    uint32_t regs_ro[CADENCE_GEM_MAXREG];
-    /* Mask of register bits which are clear on read */
-    uint32_t regs_rtc[CADENCE_GEM_MAXREG];
-    /* Mask of register bits which are write 1 to clear */
-    uint32_t regs_w1c[CADENCE_GEM_MAXREG];
-
-    /* PHY registers backing store */
-    uint16_t phy_regs[32];
-
-    uint8_t phy_loop; /* Are we in phy loopback? */
-
-    /* The current DMA descriptor pointers */
-    uint32_t rx_desc_addr;
-    uint32_t tx_desc_addr;
-
-    uint8_t can_rx_state; /* Debug only */
-
-    unsigned rx_desc[2];
-
-    bool sar_active[4];
-} CadenceGEMState;
-
 /* The broadcast MAC address: 0xFFFFFFFFFFFF */
 static const uint8_t broadcast_addr[] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
 
diff --git a/include/hw/net/cadence_gem.h b/include/hw/net/cadence_gem.h
new file mode 100644
index 0000000..f2e08e3
--- /dev/null
+++ b/include/hw/net/cadence_gem.h
@@ -0,0 +1,73 @@
+/*
+ * QEMU Cadence GEM emulation
+ *
+ * Copyright (c) 2011 Xilinx, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef CADENCE_GEM_H
+
+#define TYPE_CADENCE_GEM "cadence_gem"
+#define CADENCE_GEM(obj) OBJECT_CHECK(CadenceGEMState, (obj), TYPE_CADENCE_GEM)
+
+#include "net/net.h"
+#include "hw/sysbus.h"
+
+#define CADENCE_GEM_MAXREG        (0x00000640/4) /* Last valid GEM address */
+
+typedef struct CadenceGEMState {
+    /*< private >*/
+    SysBusDevice parent_obj;
+
+    /*< public >*/
+    MemoryRegion iomem;
+    NICState *nic;
+    NICConf conf;
+    qemu_irq irq;
+
+    /* GEM registers backing store */
+    uint32_t regs[CADENCE_GEM_MAXREG];
+    /* Mask of register bits which are write only */
+    uint32_t regs_wo[CADENCE_GEM_MAXREG];
+    /* Mask of register bits which are read only */
+    uint32_t regs_ro[CADENCE_GEM_MAXREG];
+    /* Mask of register bits which are clear on read */
+    uint32_t regs_rtc[CADENCE_GEM_MAXREG];
+    /* Mask of register bits which are write 1 to clear */
+    uint32_t regs_w1c[CADENCE_GEM_MAXREG];
+
+    /* PHY registers backing store */
+    uint16_t phy_regs[32];
+
+    uint8_t phy_loop; /* Are we in phy loopback? */
+
+    /* The current DMA descriptor pointers */
+    uint32_t rx_desc_addr;
+    uint32_t tx_desc_addr;
+
+    uint8_t can_rx_state; /* Debug only */
+
+    unsigned rx_desc[2];
+
+    bool sar_active[4];
+} CadenceGEMState;
+
+#define CADENCE_GEM_H
+#endif
