Verification Central


Rapid Adoption of Synopsys VIP for ARM AMBA 5 CHI

There was a time when coherent multi-processor systems were a niche technology with complex proprietary architectures. With ever increasing demand for performance, coherent systems with multiple processors and coherent accelerators are now being adopted rapidly across applications and market segments ranging from infrastructure networking and servers to storage and automotive. ARM® AMBA® 5 CHI provides the much needed standard architecture for coherent designs.

SoC leaders have adopted Synopsys VIP for CHI and other AMBA protocols for successful verification closure and tape out of coherent subsystems and interconnects. As a result of the pro-active collaboration with ARM to develop and prove VIP for CHI we have seen a rapid adoption of the CHI VIP and TestSuite.

ARM recently announced CHI Issue B as a part of the ARM AMBA 5 family of protocols, enhancing the standard architecture for next-generation coherent designs.


ARM AMBA 5 CHI Issue B provides following new features:

  1. Atomic operations
  2. Cache stashing to improve data locality
  3. New de-allocating and cache maintenance transactions
  4. Data check and poisoning to identify data corruption
  5. Direct data transfer to reduce latency

As part of our decade-long mutual collaboration with ARM, Synopsys announced the availability of our Verification IP and source code Test Suite for ARM AMBA 5 CHI (Coherent Hub Interface) Issue B, which occurred concurrently with ARM’s announcement.


CHI Issue B VIP enables customers and partners to verify the latest coherent system designs with new enhancements for increased performance. Below is a summary of advanced verification features of VIP:

  1. Performance metrics for latency and throughput analysis
  2. Configurable interconnect model
  3. Standard UVM architecture providing AMBA System Env, CHI System Env, as well as standalone RN and SN UVM agents
  4. Comprehensive source code Test Suites
  5. Reference veri­fication platform
  6. A System Monitor for CHI and AMBA, which performs system-level checks for protocol, data integrity and cache coherency
  7. Native integration with Verdi® Protocol Analyzer and Performance Analyzer
  8. Built-in coverage and verification plans to speed up verification coverage closure


To learn more about Synopsys VIP and Test Suites for CHI Issue B and other AMBA protocols, please visit

Authored by Ankur Jain.