A heterogeneous processor architecture and a method of booting a heterogeneous processor is described. A processor according to one embodiment comprises: a set of large physical processor cores; a set of small physical processor cores having relatively lower performance processing capabilities and relatively lower power usage relative to the large physical processor cores; and a package unit, to enable a bootstrap processor. The bootstrap processor initializes the homogeneous physical processor cores, while the heterogeneous processor presents the appearance of a homogeneous processor to a system firmware interface.