Method and apparatus for initializing a computer system that includes disabling the masking of a maskable address line

This invention relates to the field of computer systems. In particular, this invention is drawn to methods and apparatus for initializing a computer system having maskable address lines. A method of securing a boot process for a computer system enables a processor to boot from a location identified by a boot vector. The method includes the step of disabling masking of a maskable address line in response to a processor initialization event. In one embodiment, an apparatus includes a processor coupled to a memory by at least one maskable address line wherein the memory is storing a first initialization instruction. The apparatus includes a mask control wherein the mask control disables masking of the maskable address line before the processor attempts to access the first initialization instruction in response to an initialization event. In one embodiment a processor chipset gates a first address mask control with an inhibit bit to generate a second address mask control. The second address mask control is independent of the first address mask control when the inhibit bit is set to a first value. The processor chipset sets the inhibit bit to the first value in response to a processor initialization event. In various embodiments the initialization event include at least one of an application of power to the processor, a processor RESET, or a processor INIT.