RapidIO: The Next Generation Communication Fabric For Embedded Application

2.1. PHILOSOPHY

The architecture of RapidIO was driven by certain principal objectives. These objectives were related to a set of requirements unique to high-performance embedded systems. These embedded systems are the unseen technology supporting the telephone and data networks that most of us use on a daily basis. The principal objectives were:

• Focus on applications that connect devices that are within the box or chassis: this includes connectivity between devices on a printed circuit board, mezzanine board connections and backplane connections of subsystems.

• Limit the impact on software: many applications are built on a huge legacy of memory-mapped device I/O. In such applications the interconnect must not be visible to software. Abstracted interfaces such as InfiniBand require a large software re-engineering effort.

• Confine protocol overhead: because system performance is highly dependent on latency and bandwidth, it is important that the protocol impose no more overhead than is absolutely necessary.

• Partition the specifications: this limits design complexity while increasing reuse opportunities. It also enables the deployment of future enhancements without impacting the entire ecosystem.

• Manage errors in hardware: in meeting the high standards of availability it is important that the interconnect be able to detect and recover from errors. The interconnect should have the capability of detecting any errors that may occur. Further, the interconnect must utilize hardware mechanisms ...