EHCI_USBSTS
uint32 status = ReadOpReg(EHCI_USBSTS) & EHCI_USBSTS_INTMASK;
WriteOpReg(EHCI_USBSTS, status);
WriteOpReg(EHCI_USBSTS, status);
ReadOpReg(EHCI_USBCMD), ReadOpReg(EHCI_USBSTS));
uint32 status = ReadOpReg(EHCI_USBSTS);