semiwiki.com, Sept. 02, 2024 –
The Universal Chiplet Interconnect Express™ (UCIe™) 1.0 specification was announced in early 2022 and a UCIe 1.1 update was released on August 8, 2023. This open standard facilitates the heterogeneous integration of die-to-die link interconnects within the same package. This is a fancy way of saying the standard opens the door to true multi-die design, sourced from an open ecosystem that can be trusted and validated. This standard is very important to the future of semiconductor system design. It's also quite complex and presents many technical hurdles to practical usage by many. Intel and Cadence recently published a white paper that details how the two companies are working together to get to the promised land of a chiplet ecosystem. If multi-die design is in your future, you will want to get your own copy. A link is coming, but let's first examine some history and innovation as Intel and Cadence collaborate to advance the all-important UCIe standard.
Some History
It turns out Cadence and Intel have a history of collaborating to bring emerging standards into the mainstream. In 2021, the companies collaborated on simulation interoperability between an Intel host and Cadence IP for the Compute Express Link™ (CXL™) 2.0 specification. Like UCIe, this work aimed to have a substantial impact on chip and system design.
The specification, along with the latest PCI Express® (PCIe®) 5.0 specification provided a path to high-bandwidth, cache-coherent, low-latency transport for many high-bandwidth applications such as artificial intelligence, machine learning, and hyperscale applications, with specific use cases in newer memory architectures such as disaggregated and persistent memories.
The ecosystem to support this standard was rapidly evolving. Design IP, verification IP, protocol analyzers, and test equipment were all advancing simultaneously. This situation could lead to design issues not being discovered until prototype chips became available for interoperability testing. Finding the problem this late in the process would delay product introduction for sure.
So, Intel and Cadence collaborated on interoperability testing through co-simulation as the first proof point to successfully run complex cache coherent flows. This "shift-left" approach demonstrated the ability to confidently build host and device IP, while also providing essential feedback to the CXL standards body.