Heci3Smm

Index

0187

Size

3964h (14,692 bytes)

Phase

DXE SMM (System Management Mode driver)

Source Package

PurleySktPkg/Me/Heci/SmmHeci3 (MeHeci3Smm)

Overview

Heci3Smm is an SMM driver that manages the third HECI (Host Embedded Controller Interface) controller channel within System Management Mode. On the Purley platform, there are multiple HECI controllers (HECI1, HECI2, HECI3), each serving different communication channels between the host and the Intel Management Engine (ME). This driver specifically handles HECI3, which is used for isolated management traffic with stricter security requirements.

Key Functions

• ModuleEntryPoint (0x4B4): Entry point; initializes HECI3 interface for SMM-mode operation.
• sub_560: HECI3 hardware initialization; configures registers and verifies HECI3 device presence.
• sub_950: Core HECI3 message transfer; handles secure communication with ME over the HECI3 channel.
• sub_18B0 (5 callees): HECI3 protocol message processing and dispatch.
• sub_FE0 (10 callees): Deeper HECI message handling; implements retry and timeout logic for ME communication.
• sub_1F68: Error handling for HECI3 communication failures.

Strings

• "!EFI_ERROR (((RETURN_STATUS)(0x8000000000000000ULL | (2))))" (specific error code checks)
• "!EFI_ERROR (((RETURN_STATUS)(0x8000000000000000ULL | (7))))"
• Build path: PurleySktPkg\Me\Heci\SmmHeci3\MeHeci3Core.c
• AutoGen.c debug assertions (lines 463, 478)

Libraries Referenced

• HeciCoreLib (PurleySktPkg)
• SmmMmPciBaseLib (CpRcPkg)
• SmmMemoryAllocationLib
• DxePcdLib

Platform

Intel Purley (HR650X server platform)