A METHOD TO USE GLOBAL VARIABLES FOR PRE-EFI INITIALIZATION MODULES IN EFI-BASED FIRMWARE

摘要

A method for enabling global variable read/write operations in a pre-EFI Initialization (PEI). The method includes the generation of a driver image. The driver image includes at least a code (i.e., text) section, a data section, and a relocation section. A first round fixing on the driver image is performed to fix all address data items with absolute non-volatile memory addresses. A second round fixing on the driver image is performed to fix all address data items fixed in the first round fixing that point to the data section with absolute Cache-As-RAM (Cache-As-Random Access Memory) addresses. The fixed driver image is burned into a non-volatile memory device. Upon booting the non-volatile memory device, the data section of the burned driver image is copied to a Cache-As-RAM (CAR), wherein execution of executable code in the text section enables static and global variables to have read/write access from the CAR.