A new configuration file and core v target is added to start working on a 64 bit CVA6 core.
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Co-authored-by: JeanRochCoulon <jean-roch.coulon@thalesgroup.com>
Introduction
This PR adds support for Zbkb extension in the CVA6 core. It also adds the documentation for this extension. These changes have been tested with self-written single instruction tests and with the riscv-arch-tests. This PR will be followed by other PRs that will add complete support for the Zkn - NIST Algorithm Suite extension.
Implementation
Zbkb Extension:
Added support for the Zbkb instruction set. It essentially expands the Zbb extension with additional instructions useful in cryptography. These instructions are pack, packh, packw, brev8, unzip and zip.
Modifications
1. A new bit ZKN was added. The complete Zkn extension will be added under this bit for ease of use. This configuration will also require the RVB (bitmanip) bit to be set.
2. Updated the ALU and decoder to recognize and handle Zbkb instructions.
Documentation and Reference
The official RISC-V Cryptography Extensions Volume I was followed to ensure alignment with ratification. The relevant documentation for the Zbkb instruction was also added.
Verification
Assembly Tests:
The instructions were tested and verified with the K module of both 32 bit and 64 bit versions of the riscv-arch-tests to ensure proper functionality. These tests check for ISA compliance, edge cases and use assertions to ensure expected behavior. The tests include:
pack-01.S
packh-01.S
packw-01.S
brev8-01.S
unzip-01.S
zip-01.S
Update CV32A65X-annotated privileged ISA specification to reflect the fact that with PMP granularity 8 and only supported PMP address matching modes being OFF and TOR, bit 0 of the pmpaddr0..pmpaddr7 registers can be safely made read-only zero. Update riscv-config specifications and its generated files accordingly.
Update riscv-config spec files and Spike Yaml file for CV32A65X.
Bump CVV to change Spike default PMP granularity to 8 and to include corresponding Spike Yaml parameter.
Both the ISA and design documentations use some parameters generated from the RTL (ports, parameters).
As of now, they are committed to the repository and can be out of sync with the code.
This PR removes them from the repository and freshly generates them from the code when building HTML files.
This PR also removes prebuilt HTML files (design & ISA docs) and generates them when building the top-level Read the Docs documentation (make -C docs).
- FIX: Replace riscv_pkg:VLEN by CVA6Cfg.VLEN
- Declare VLEN as new CVA6 parameter
- smoke-hwconfig: run with vcs-uvm and use return0 tests to speed-up CI light stage timing execution
- Use dedicated linker scripts for 65x configuration.
- Use dedicated spike.yaml for 65x configuration.
- Set BHTEntries=128, cache=WT, scoreboard entries=8 to improve Coremark and Dhrystone results
- Run 4 iterations of coremark to improve results
