What is the OpenSPARC Project?

OpenSPARC project is making the hardware source code of the UltraSPARC T1 processor available under an Open Source license.

This technology offers a wide range of innovative opportunities not yet explored. By lowering the costs of entry to leverage a current hardware design, more developers can engage in the process, and more specialized implementations can be pursued.

What is "Open Source" Hardware?

The term "Open Source" today most often refers to "Free/Libre or Open Source Software, (FL/OSS)." While it is not a perfect term in the hardware space, we consider "Open Source" as a reference to the development process, where we are providing free and open tools that are essential components to developing a new chip.

Our goal to encourage an open, collaborative process around developing new chips. Until now, chip design and development has almost exclusively been a closely guarded, proprietary event.

Is there any cost to using the code?

No. There are no fees associated with downloading the code from this site.

What open source licensing model are you using the code?

We have selected GPL v2. See Licensing FAQs for more details.

What role does SPARC International play in this?

SPARC International was created in 1989 as an independent, non-profit organization. The Corporation's purpose is to promote the design, development, and application of SPARC (Scalable Processor ARChitecture) to computer and related products, and to control, maintain, and enforce SPARC trademarks. Sun has open-sourced an implementation of the SPARC architecture; the open-source implementation is independent of the oversight provided by SPARC International. SPARC International continues to provide SPARC compliance test suites to developers who wish to certify and brand their own implementation based on SPARC architectures. To become a SPARC International member, obtain information for compliance test suites, or to get answers to trademark questions contact: This e-mail address is being protected from spam bots, you need JavaScript enabled to view it .

Who do you expect to be key contributors to this project?

We have received a tremendous amount of interest from universities, small design companies, embedded device manufacturers, and network specialists in understanding the 64-bit processor environment and multithreading capabilities. We expect now that the RTL is available, the interest level among these groups and others will grow significantly.

How does this introduction help solve some of the deterrents to designing a "System on a Chip (SOC)?

The SOC design movement involves integrating functional units onto a single chip that, even just a few years ago, would have been spread across several chips or even a whole system. SOC designs are increasingly important because they can lower product costs while improving both performance and reliability. They also can speed up product design cycles.

The SOC design movement currently faces two intractable problems. First, it's very difficult to get access to the wide range of IP potentially of interest in the various different single chip designs now feasible. Secondly, it's very hard to acquire the separate pieces selected for integration on a given chip in a compatible form that lets them all interconnect and interoperate as required. If similar license models were adopted widely across the semiconductor industry, it would solve both these problems. Designers not only would have free and immediate access to all the IP of possible interest to them, but all IP would be available in a "soft" format that facilities both easy customization and ready integration.

What are the benefits to the user?

We realize from existing projects using the Open Source development model that while we can make some predictions, the most exciting results occur unexpectedly. The creation of a vibrant community built around a 64-bit, thread-rich implementation will bring more choices and applications to the market faster.

What are the benefits to developers?

Opening the UltraSPARC T1 source code lets developers create innovative software applications faster, and with a higher degree of hardware integration than ever before. Software developers will now be able to create highly optimized applications that are tightly integrated with the hardware, creating unique, high-value solutions for specific markets.

What are the benefits to Sun?

We expect this open source strategy will help create new markets for the 64-bit, multithreading features offered by UltraSPARC T1 and its derivatives. As in software, innovation happens everywhere, and the hardware community can make huge strides with current, accessible, low-cost technology at their fingertips.

With added "eyes" addressing the challenges and opportunities around multithreading and 64-bit processes, Sun's products - along with new products by other companies - can evolve more quickly and attract more customers.

How does the OpenSPARC project model differ from other models for processor cores?

We are not aware of any other major company that posts 64-bit, multi-threaded processor core IP on a Web site where anyone can download it under an OSI-Approved open source license.

Why would Sun "open" its current hardware chip design?

We also believe the open source model can help solve some serious issues created by more traditional licensing terms in a rapidly-changing semiconductor industry. In particular, we think it can be a key enabler for the increasingly important "System On a Chip" (SOC) design business.

Why are you opening the source code for the UltraSPARC T1?

Sun's 64-bit UltraSPARC processors have been an industry standard for more than a decade. Our goal is to expand the SPARC community and lay the groundwork for a new generation of 64-bit hardware and multi-threaded software products. Sun has a long history of being associated with open standards and specifications and opening up the UltraSPARC-T1 design point is part of our overall open source strategy.

What parts to the chip design are you "Open Sourcing?"

The source of the design in Verilog, a verification suite and simulation models, ISA specification (UltraSPARC Architecture 2005), and a software simulation model for Solaris that gives developers a rapid means of developing and testing software functionality in the absense of actual hardware. See Question 31 for more details.

Who do I contact at Sun if I have additional questions?

If you have a general question whose answer would benefit the community, post it to the forums. If your question is more specific to your own development needs, send an email to This e-mail address is being protected from spam bots, you need JavaScript enabled to view it .