The Open Core Protocol's unique flexibility, configurability and scalability characteristics enable integrators to build complex systems for high-performance domains A complete standardization process describing how OCP cores and systems can be captured in IP-XACT is the end goal.
The IP-XACT specifications, delivered by The Spirit Consortium is enabling and standardizing
effective IP reuse. Members of the consortium are EDA providers (Mentor Graphics, Synopsys,
Cadence), IP providers (ARM) and system integrators (TI, NXP, ST).
The IP-XACT specs are defining human-readable documentation for language-independent, interoperable IP module descriptions and tool interfaces using an XML databook format.
The IP-XACT description can document, for example, an IP interface, its registers and bit fields, pointers to the
VHDL or SystemC files which define its RTL or TLM implementation, or its software views.
As an example, a third-party UART IP, packaged in an IP-XACT XML format, may be associated with an IP-XACT compliant configuration script by its provider.
The system integrator who receives this UART can automatically import it into his IP-XACT compliant platform assembly tool and integrate it into his existing sub-system (which is also being captured in IP-XACT).
The IP-XACT compliant configuration script may be directly launched into the same tool, and additional connections/parameterization performed. When
completed, this sub-system IP-XACT description may be shipped to another team or company for integration into the full system in the same way (possibly using a different IP-XACT compliant assembly tool since they will still remain interoperable).
In addition, specific executables (called "generators" using IP-XACT terminology) may process
the IP-XACT descriptions and perform various automated tasks, such as launching checks,
creating connections automatically, generating a VHDL platform netlist or dumping register lowlevel
API C header files.
Practical benefits of this OCP and IP-XACT based methodology have been recently demonstrated by a customer of Magillem Design Services, an American semiconductor company.
Magillem Design Services, as a member of both OCP-IP organization and The Spirit Consortium, has brought its expertise to help this client move to this methodology for its next generation of wireless chips.
Using Magillem, our IP-XACT flagship Design Environment, different engineering teams have
been able to exchange, integrate and build complex platforms and generate the corresponding
VHDL netlist from the IP-XACT descriptions.
Other examples of the types of automated tasks natively performed by Magillem or through
specific IP-XACT generators are:
insertion of isolation cells at multiple levels of hierarchy
connectivity checking (for example to verify that no port was left dangling beforeshipping this system to the verification team)
automatic connection of OCP interfaces
connection of ports between different levels of hierarchy, based on naming conventions, for example.
As a direct result of this approach, more than 70 percent of all connections in one particular system
have been automated (instead of 35 percent with the previous methodology); which directly translates
to significant gains due to the reduction of time during the assembly process.
OCP extensions for IP-XACT 1.4
Although IP-XACT 1.4, the latest version of the IP-XACT specifications, enables users to capture OCP core descriptions (such as OCP interfaces at RTL or TLM levels, ports and parameters) and OCP connections between core interfaces (including connections for OCP
dataflow and sideband signals), it does not support natively the full configurability features of an OCP interface, where a change of an OCP parameter value enables the addition of a new signal
on this interface.
Nevertheless, this limitation has been overcome by leveraging the extension mechanism, included natively in IP-XACT. This extension feature allows users to add specific elements to the IP-XACT descriptions (into the dedicated "vendor extensions" part) providing missing or customer-specific information, while leaving these descriptions still fully IP-XACT compliant.
In collaboration with Sonics Inc. , Magillem Design Services has defined extensions to IP-XACT
1.4, which enable full configurability of OCP interfaces and automated checking of their configuration.
Magillem Design Environment now supports these extensions on top of IP-XACT 1.4 descriptions, enabling users to easily capture the particular configuration of an OCP interface, check a particular OCP parameterization, and easily make connections between OCP master and
The immediate benefits of using these extensions have been, for example, early detection of OCP configuration mismatch and easier parameterization of OCP interfaces. As a result, this leads to better customer confidence in design correctness, and increased automation during OCP interface parameterization.
Donation to OCP-IP consortium
As a next step, these extensions have been donated to the OCP-IP organization through its Meta Data Working Group, where they have been refined and standardized in collaboration with STMicroelectronics.
The Meta Data Working Group now plans to share these extensions and validate them on other
real-life use cases.
The final goal is complete standardization describing how OCP cores and systems can be captured in IP-XACT; enabling efficient and increased IP reuse across the full OCP ecosystem.
Stéphane Guntz is Project Manager for Magillem tool at Magillem Design Services. In addition, he is also a member of the Spirit consortium Electronic System-Level Working Group and OCP-IP Metadata Working Group. Guntz graduated with a Masters degree from the Grenoble Polytechnic National Institute (France).