Uhcd

USB Host Controller Driver (xHCI) for the Lenovo HR650X platform. This AMI-proprietary driver manages xHCI controllers including driver entry and UHCD protocol installation, xHCI controller enumeration and initialization, USB device tree management (add/remove/update), control/bulk/interrupt/isochronous transfer scheduling, root hub emulation with port status and feature control, timer-based polling for interrupt transfers, and memory pool management for runtime USB data structures. The driver defines a large global context structure (~30KB) allocated from runtime memory and a private vtable for internal helper dispatch.

Key Functions

• ModuleEntryPoint -- Driver entry; allocates gUsbData context and installs UHCD protocol
• LocateAndInitXhciController -- Enumerates and initializes xHCI host controllers
• XhciCapabilityProbe -- Probes xHCI capability registers for version and structural parameters
• UsbRtAllocPages -- Runtime memory pool allocation for USB data structures
• UsbDeviceTreeAdd/Remove/Update -- USB device tree management
• UsbTransferSchedule -- Schedules control/bulk/interrupt/isochronous transfers on xHCI

Dependencies

• UefiBootServicesTableLib, UefiRuntimeServicesTableLib
• DebugLib, BaseLib, TimerLib
• CPU IO2 Protocol, UHCD Protocol (AMI proprietary)

Platform

x86-64 PE32+ (UEFI DXE driver), Lenovo HR650X (Purley/Intel grantley-EP), AMI ModulePkg (Usb module)