OemPlatformEarlyPhasePei

Overview

OemPlatformEarlyPhasePei handles early Lenovo platform initialization during PEI, focusing on CMOS-based UART baud rate configuration. It reads the baud rate from CMOS, synchronizes it with Setup variables, and triggers a warm reset if a mismatch is detected. The module also provides low-level IDT/PEI services table pointer retrieval used by other early-phase routines.

Key Functions

• ReadIdtr -- Reads the IDT register for PEI services table pointer extraction
• GetPeiServicesTablePtr -- Retrieves the PEI Services Table via IDT
• ModuleEntryPoint -- Main entry: performs CMOS baud rate sync and reset logic
• BaudRateCheck -- Compares CMOS baud rate to Setup variable; triggers warm reset on mismatch

Dependencies

• CMOS RTC (ports 0x70/0x71)
• IDT/SIDT instruction
• PEI Services
• UART/I/O Library (IoLib)

Platform

• Architecture: IA32 (x86, PE32)
• Subsystem: EFI Boot Service Driver (0x000B)
• Machine: 0x014C (i386)
• Entry Point: 0x315