PiSmmCommunicationPei

Overview

PiSmmCommunicationPei is a PEI module from UefiCpuPkg that establishes communication between the PEI phase and SMM (System Management Mode) foundation. It installs a SMM communication protocol that allows PEIMs to transfer data to SMM drivers during S3 resume. On S3 boot path (BOOT_ON_S3_RESUME), it initializes the communication buffer, sets up the SMM configuration table pointer, and installs a PPI for SMM communication.

Key Functions

• ModuleEntryPoint_0 -- Main entry; verifies S3 resume boot mode (BOOT_ON_S3_RESUME), initializes communication context
• sub_FFE32A96 -- Initializes SMM communication context; reads SMM S3 Resume State HOB, resolves Smst address
• sub_FFE329BA -- Searches SMM configuration tables for PiSmmCommunicationSmm matching GUID
• sub_FFE32B5C -- Communicates with SMM core; writes buffer pointer to SMM-shared memory, triggers SMI
• sub_FFE32ED1 / sub_FFE32E8C -- GUID HOB traversal and matching
• sub_FFE32F04 / sub_FFE32F54 -- HOB allocation for communication structures

Dependencies

• UefiCpuPkg/PiSmmCommunication
• PEI Services (for PPI installation and notification)
• HOB services (for SMM S3 Resume State and configuration table HOBs)
• IDT-based PEI Services Table Pointer Library
• SMM communication PPI (gEfiPeiSmmCommunicationPpiGuid)

Platform

• Architecture: IA-32 (x86)
• Subsystem: EFI_BOOT_SERVICE_DRIVER (0x0B)
• Source: UefiCpuPkg/PiSmmCommunication/PiSmmCommunicationPei.c
• Linker: MSVS 2015