This protocol defines the generic memory test interfaces in Dxe phase.
Include/Protocol/GenericMemoryTest.h

PROTOCOL Information

PROTOCOL's Guid Name	PROTOCOL's Guid
gEfiGenericMemTestProtocolGuid	{ 0x309DE7F1, 0x7F5E, 0x4ACE, { 0xB4, 0x9C, 0x53, 0x1B, 0xE5, 0xAA, 0x95, 0xEF }}

Refer to Header File