The MultiProcessor Specification, hereafter known as the "MP specification," defines an
enhancement to the standard to which PC manufacturers design DOS-compatible systems.
MP-capable operating systems will be able to run without special customization on multiprocessor
systems that comply with this specification. End users who purchase a compliant multiprocessor
system will be able to run their choice of operating systems.
The MP specification covers PC/AT-compatible MP platform designs based on Intel processor
architectures and Advanced Programmable Interrupt Controller (APIC) architectures. The term
"PC/AT-compatible" here refers to the software-visible components of the PC/AT, not to hardware
features, such as the bus implementation, that are not visible to software. An implementation of
this specification may incorporate one or more industry standard buses, such as ISA, EISA, MCA,
PCI, or other OEM-specific buses.
The intent of this specification is to establish an MP Platform interface standard that extends the
performance of the existing PC/AT platform beyond the traditional single processor limit, while
maintaining 100% PC/AT binary compatibility.
The ultimate goal is to enable scalable, high-end workstations and enterprise server systems that
provide computer users with superior price/performance and have the ability to execute all existing
AT binaries, as well as MP-ready software packages on shrink-wrapped MP operating systems.
Figure 1-1 shows that at the heart of the specification are the data structures that define the
configuration of the MP system. The BIOS constructs the MP configuration data structures,
presenting the hardware in a known format to the standard device drivers or to the hardware
abstraction layer of the operating system. The specification details default hardware
configurations, and, for added flexibility, outlines extensions to the standard BIOS.
Figure 1-1. Conceptual Overview