Cache Coherent Verification - New Features in AMBA CHI May. 31, 2021 Coherent Hub Interface, popularly known as CHI, is an Interface specification that is part of 5th generation of AMBA® protocols (AMBA® 5) from Arm, released in 2013. AMBA® 5 CHI defines the interfaces for connection of fully coherent processors and dynamic memory controllers, to high performance non-blocking interconnects. AMBA®CHI-E built on top of existing AMBA® CHI-D (Issue D) specification (refer to our blog on AMBA®CHI-D), introduces the support for– a set of new transactions, exclusive access features, transaction optimizations, series of performance throughput improvement features and key Arm architecture features. Some of the new features include: