diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c
index a3ae9f2..a00a93c 100644
--- a/hw/usb/hcd-ehci.c
+++ b/hw/usb/hcd-ehci.c
@@ -27,87 +27,10 @@
  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
+#include "hw/usb/ehci-regs.h"
 #include "hw/usb/hcd-ehci.h"
 #include "trace.h"
 
-/* Capability Registers Base Address - section 2.2 */
-#define CAPLENGTH        0x0000  /* 1-byte, 0x0001 reserved */
-#define HCIVERSION       0x0002  /* 2-bytes, i/f version # */
-#define HCSPARAMS        0x0004  /* 4-bytes, structural params */
-#define HCCPARAMS        0x0008  /* 4-bytes, capability params */
-#define EECP             HCCPARAMS + 1
-#define HCSPPORTROUTE1   0x000c
-#define HCSPPORTROUTE2   0x0010
-
-#define USBCMD           0x0000
-#define USBCMD_RUNSTOP   (1 << 0)      // run / Stop
-#define USBCMD_HCRESET   (1 << 1)      // HC Reset
-#define USBCMD_FLS       (3 << 2)      // Frame List Size
-#define USBCMD_FLS_SH    2             // Frame List Size Shift
-#define USBCMD_PSE       (1 << 4)      // Periodic Schedule Enable
-#define USBCMD_ASE       (1 << 5)      // Asynch Schedule Enable
-#define USBCMD_IAAD      (1 << 6)      // Int Asynch Advance Doorbell
-#define USBCMD_LHCR      (1 << 7)      // Light Host Controller Reset
-#define USBCMD_ASPMC     (3 << 8)      // Async Sched Park Mode Count
-#define USBCMD_ASPME     (1 << 11)     // Async Sched Park Mode Enable
-#define USBCMD_ITC       (0x7f << 16)  // Int Threshold Control
-#define USBCMD_ITC_SH    16            // Int Threshold Control Shift
-
-#define USBSTS           0x0004
-#define USBSTS_RO_MASK   0x0000003f
-#define USBSTS_INT       (1 << 0)      // USB Interrupt
-#define USBSTS_ERRINT    (1 << 1)      // Error Interrupt
-#define USBSTS_PCD       (1 << 2)      // Port Change Detect
-#define USBSTS_FLR       (1 << 3)      // Frame List Rollover
-#define USBSTS_HSE       (1 << 4)      // Host System Error
-#define USBSTS_IAA       (1 << 5)      // Interrupt on Async Advance
-#define USBSTS_HALT      (1 << 12)     // HC Halted
-#define USBSTS_REC       (1 << 13)     // Reclamation
-#define USBSTS_PSS       (1 << 14)     // Periodic Schedule Status
-#define USBSTS_ASS       (1 << 15)     // Asynchronous Schedule Status
-
-/*
- *  Interrupt enable bits correspond to the interrupt active bits in USBSTS
- *  so no need to redefine here.
- */
-#define USBINTR              0x0008
-#define USBINTR_MASK         0x0000003f
-
-#define FRINDEX              0x000c
-#define CTRLDSSEGMENT        0x0010
-#define PERIODICLISTBASE     0x0014
-#define ASYNCLISTADDR        0x0018
-#define ASYNCLISTADDR_MASK   0xffffffe0
-
-#define CONFIGFLAG           0x0040
-
-/*
- * Bits that are reserved or are read-only are masked out of values
- * written to us by software
- */
-#define PORTSC_RO_MASK       0x007001c0
-#define PORTSC_RWC_MASK      0x0000002a
-#define PORTSC_WKOC_E        (1 << 22)    // Wake on Over Current Enable
-#define PORTSC_WKDS_E        (1 << 21)    // Wake on Disconnect Enable
-#define PORTSC_WKCN_E        (1 << 20)    // Wake on Connect Enable
-#define PORTSC_PTC           (15 << 16)   // Port Test Control
-#define PORTSC_PTC_SH        16           // Port Test Control shift
-#define PORTSC_PIC           (3 << 14)    // Port Indicator Control
-#define PORTSC_PIC_SH        14           // Port Indicator Control Shift
-#define PORTSC_POWNER        (1 << 13)    // Port Owner
-#define PORTSC_PPOWER        (1 << 12)    // Port Power
-#define PORTSC_LINESTAT      (3 << 10)    // Port Line Status
-#define PORTSC_LINESTAT_SH   10           // Port Line Status Shift
-#define PORTSC_PRESET        (1 << 8)     // Port Reset
-#define PORTSC_SUSPEND       (1 << 7)     // Port Suspend
-#define PORTSC_FPRES         (1 << 6)     // Force Port Resume
-#define PORTSC_OCC           (1 << 5)     // Over Current Change
-#define PORTSC_OCA           (1 << 4)     // Over Current Active
-#define PORTSC_PEDC          (1 << 3)     // Port Enable/Disable Change
-#define PORTSC_PED           (1 << 2)     // Port Enable/Disable
-#define PORTSC_CSC           (1 << 1)     // Connect Status Change
-#define PORTSC_CONNECT       (1 << 0)     // Current Connect Status
-
 #define FRAME_TIMER_FREQ 1000
 #define FRAME_TIMER_NS   (1000000000 / FRAME_TIMER_FREQ)
 #define UFRAME_TIMER_NS  (FRAME_TIMER_NS / 8)
diff --git a/include/hw/usb/ehci-regs.h b/include/hw/usb/ehci-regs.h
new file mode 100644
index 0000000..616f1b8
--- /dev/null
+++ b/include/hw/usb/ehci-regs.h
@@ -0,0 +1,82 @@
+#ifndef HW_USB_EHCI_REGS_H
+#define HW_USB_EHCI_REGS_H 1
+
+/* Capability Registers Base Address - section 2.2 */
+#define CAPLENGTH        0x0000  /* 1-byte, 0x0001 reserved */
+#define HCIVERSION       0x0002  /* 2-bytes, i/f version # */
+#define HCSPARAMS        0x0004  /* 4-bytes, structural params */
+#define HCCPARAMS        0x0008  /* 4-bytes, capability params */
+#define EECP             HCCPARAMS + 1
+#define HCSPPORTROUTE1   0x000c
+#define HCSPPORTROUTE2   0x0010
+
+#define USBCMD           0x0000
+#define USBCMD_RUNSTOP   (1 << 0)      // run / Stop
+#define USBCMD_HCRESET   (1 << 1)      // HC Reset
+#define USBCMD_FLS       (3 << 2)      // Frame List Size
+#define USBCMD_FLS_SH    2             // Frame List Size Shift
+#define USBCMD_PSE       (1 << 4)      // Periodic Schedule Enable
+#define USBCMD_ASE       (1 << 5)      // Asynch Schedule Enable
+#define USBCMD_IAAD      (1 << 6)      // Int Asynch Advance Doorbell
+#define USBCMD_LHCR      (1 << 7)      // Light Host Controller Reset
+#define USBCMD_ASPMC     (3 << 8)      // Async Sched Park Mode Count
+#define USBCMD_ASPME     (1 << 11)     // Async Sched Park Mode Enable
+#define USBCMD_ITC       (0x7f << 16)  // Int Threshold Control
+#define USBCMD_ITC_SH    16            // Int Threshold Control Shift
+
+#define USBSTS           0x0004
+#define USBSTS_RO_MASK   0x0000003f
+#define USBSTS_INT       (1 << 0)      // USB Interrupt
+#define USBSTS_ERRINT    (1 << 1)      // Error Interrupt
+#define USBSTS_PCD       (1 << 2)      // Port Change Detect
+#define USBSTS_FLR       (1 << 3)      // Frame List Rollover
+#define USBSTS_HSE       (1 << 4)      // Host System Error
+#define USBSTS_IAA       (1 << 5)      // Interrupt on Async Advance
+#define USBSTS_HALT      (1 << 12)     // HC Halted
+#define USBSTS_REC       (1 << 13)     // Reclamation
+#define USBSTS_PSS       (1 << 14)     // Periodic Schedule Status
+#define USBSTS_ASS       (1 << 15)     // Asynchronous Schedule Status
+
+/*
+ *  Interrupt enable bits correspond to the interrupt active bits in USBSTS
+ *  so no need to redefine here.
+ */
+#define USBINTR              0x0008
+#define USBINTR_MASK         0x0000003f
+
+#define FRINDEX              0x000c
+#define CTRLDSSEGMENT        0x0010
+#define PERIODICLISTBASE     0x0014
+#define ASYNCLISTADDR        0x0018
+#define ASYNCLISTADDR_MASK   0xffffffe0
+
+#define CONFIGFLAG           0x0040
+
+/*
+ * Bits that are reserved or are read-only are masked out of values
+ * written to us by software
+ */
+#define PORTSC_RO_MASK       0x007001c0
+#define PORTSC_RWC_MASK      0x0000002a
+#define PORTSC_WKOC_E        (1 << 22)    // Wake on Over Current Enable
+#define PORTSC_WKDS_E        (1 << 21)    // Wake on Disconnect Enable
+#define PORTSC_WKCN_E        (1 << 20)    // Wake on Connect Enable
+#define PORTSC_PTC           (15 << 16)   // Port Test Control
+#define PORTSC_PTC_SH        16           // Port Test Control shift
+#define PORTSC_PIC           (3 << 14)    // Port Indicator Control
+#define PORTSC_PIC_SH        14           // Port Indicator Control Shift
+#define PORTSC_POWNER        (1 << 13)    // Port Owner
+#define PORTSC_PPOWER        (1 << 12)    // Port Power
+#define PORTSC_LINESTAT      (3 << 10)    // Port Line Status
+#define PORTSC_LINESTAT_SH   10           // Port Line Status Shift
+#define PORTSC_PRESET        (1 << 8)     // Port Reset
+#define PORTSC_SUSPEND       (1 << 7)     // Port Suspend
+#define PORTSC_FPRES         (1 << 6)     // Force Port Resume
+#define PORTSC_OCC           (1 << 5)     // Over Current Change
+#define PORTSC_OCA           (1 << 4)     // Over Current Active
+#define PORTSC_PEDC          (1 << 3)     // Port Enable/Disable Change
+#define PORTSC_PED           (1 << 2)     // Port Enable/Disable
+#define PORTSC_CSC           (1 << 1)     // Connect Status Change
+#define PORTSC_CONNECT       (1 << 0)     // Current Connect Status
+
+#endif /* HW_USB_EHCI_REGS_H */