7.2. The RISC-V ISA Simulator (Spike)¶
Spike is the golden reference functional RISC-V ISA C++ sofware simulator. It provides full system emulation or proxied emulation with HTIF/FESVR. It serves as a starting point for running software on a RISC-V target. Here is a highlight of some of Spikes main features:
- Multiple ISAs: RV32IMAFDQCV extensions
- Multiple memory models: Weak Memory Ordering (WMO) and Total Store Ordering (TSO)
- Privileged Spec: Machine, Supervisor, User modes (v1.11)
- Debug Spec
- Single-step debugging with support for viewing memory/register contents
- Multiple CPU support
- JTAG support
- Highly extensible (add and test new instructions)
In most cases, software development for a Chipyard target will begin with functional simulation using Spike (usually with the addition of custom Spike models for custom accelerator functions), and only later move on to full cycle-accurate simulation using software RTL simulators or FireSim.
Spike comes pre-packaged in the RISC-V toolchain and is available on the path as
More information can be found in the Spike repository.