Open Core Protocol
The Open Core Protocol is a protocol for on-chip subsystem communications.
It is an openly licensed, core-centric protocol and defines a bus-independent, configurable interface. OCP International Partnership produces OCP specifications. OCP data transfer models range from simple request-grant handshaking through pipelined request-response to complex out-of-order operations.
Legacy IP cores can be adapted to OCP, while new implementations may take advantage of advanced features: designers select only those features and signals encompassing a core's specific data, control and test configuration.
The Open Core Protocol is one of several FPGA processor interconnects used to connect soft FPGA peripherals to FPGA CPUs—both soft microprocessor and hard-macro processor.
Other such interconnects include
Advanced eXtensible Interface,
Avalon,
and the Wishbone bus.
FPGA vendor Altera joined the Open Core Protocol International Partnership in 2010.
Advantages
- Eliminates the ongoing task of interface protocol definition, verification, documentation and support
- Readily adapts to support new core capabilities
- Test bench portability simplifies verification
- Limits test suite modifications for core enhancements
- Interfaces to any bus structure or on-chip network
- Delivers industry-standard flexibility and reuse
- Point-to-point protocol can directly interface two cores
Disadvantages
- Neither Altera nor Xilinx, the two largest FPGA vendors, supports this protocol.