SiInitPreMem

Overview

SiInitPreMem is the PEI pre-memory silicon initialization module for the Intel Purley platform (Lewisburg PCH). It runs during the PEI pre-memory phase and configures critical PCH subsystems before system DRAM is available. At 121 KB, this is the largest module in the group, containing 134 decompiled functions covering PCH reset callbacks, early register programming, silicon policy initialization, and performance measurement logging.

Key Functions

• SiInitPrePolicy -- One-time PCH pre-memory policy initialization (guarded by flag at 0xFA044).
• PchResetInitCallback -- PCH reset initialization callback.
• PchResetCallback2 -- Secondary PCH reset handler.
• PeiPerfInit / PeiPerfLogEntry / PeiPerfLogEnd -- Performance measurement HOB logging.
• GetBootMode / GetPlatformType -- Platform boot mode and type detection.

Dependencies

• PEI Services (pre-memory phase)
• PCH Reset registers
• PCD Database
• Performance measurement (Perf) PPIs

Platform

• Architecture: IA32 (x86, PE32)
• Source: PurleySktPkg/SouthClusterLbg/SiInit/Pei/SiInitPreMem.c
• PCH Family: Lewisburg (LBG)
• Image base: 0xFFD7F40C
• Image size: 121 KB