7.4 Required Functions

The following functions are required to exist and to execute in the given order. The component that provides the function is not specified because it is not required by the architecture.

* In the common EDK II open source code.

The required functions for Stage IV are presented organized by phase and subsystem (e.g. ACPI, SMM, etc). See Appendix: Full Functions Map for a complete ordering for all stages.

7.4.1 Required PEI functions

Name

Purpose

PeimEntryMA (*)

Entry point for the TPM2 PEIM

IntelVTdPmrInitialize (*)

Entry point for the VT-d PEIM

Table 59 Stage V PEI Functions

* In the common EDK II open source code.

7.4.2 Required DXE functions

Name

Purpose

DriverEntry (*)

Entry point for the TPM2 DXE module

IntelVTdInitialize(*)

Entry point for the VT-d DXE module

UserPhysicalPresent (*)

Indicates whether a physical user is present for UEFI secure boot

ProcessTcgPp

Process the TPM physical presence (PP) request

ProcessTcgMor

Process the TPM memory overwrite request (MOR)

Table 60 Stage V DXE Functions

* In the common EDK II open source code.

7.4.3 Required SMM functions

Name

Purpose

InitializeTcgSmm (*)

Entry point for the TPM2 SMM module

MemoryClearCallback (*)

Callback function for setting the MOR variable

Table 61 Stage V SMM Functions

* In the common EDK II open source code.