Rewrite ConvPerChannelD1OD24_5x5

This new approach utilizes the aconv instruction to perform full matmul.
Creative data shuffling methods allow the implementation to achieve
significantly better useful MAC throughput.

Activation min/max is assumed to be int8 limits to eliminate the clamping
instructions in the postprocessing

ambient_face_2.8.0_504x378_grayscale_per_axis_simulator_iss is used in
The following items are measured on the simulator:
- Mismatch_count is 0.
- #0 CONV_2D takes 1.52M ticks (down from 4.02M, 2.64x speedup).
- Total cycles is now 52.9M (down from 57.9M, -8.6%).

The implementation currently contains lots of repeated and near-repeated
sections. They can be folded together in the future to improve

The following improvement items may be doable:
- Further tweak data shuffling sections to take less time
- Rearrange instructions on bottlenecks

Change-Id: Ibfcea94988b9ece4ea98a61c139ce44e967b4fd8
2 files changed
tree: 04fc28e34b12f679cd8c2c3c15a3f8955d2c0abe
  1. benchmarks/
  2. build_tools/
  3. crt/
  4. docs/
  5. examples/
  6. host_tools/
  7. platforms/
  8. tests/
  9. tflm/
  10. third_party/
  11. toolchains/
  12. .bazelrc
  13. .bazelversion
  14. .gitignore
  17. PREUPLOAD.cfg

Kelvin SW Repository

This project contains the BSP to build the SW artifact that can run on the Kelvin core, and integrated as part of the Shodan repository.

The project supports two build systems -- Bazel and CMake -- for OSS integration reasons. Bazel is used by TFLM flow, while CMake is the build system for IREE.


If you get this project from Project Shodan manifest, you are all set. If not, you need to have following projects as well to build the project successfully.

  • Kelvin crosscompile toolchain: Under <dir>/cache/toolchain_kelvin

This project needs to be at <dir>/sw/kelvin.

Code structure

  • build_tools: Build tool/rules for both Bazel and CMake
  • crt: Kelvin BSP
  • examples: Source code to build Kelvin SW artifacts.
  • host_tools: host tool to generate the intrinsic header and toolchain op files
  • platforms: Crosscompile platform setup for Bazel.
  • tests: Tests to exercise features of the Kelvin core.
  • tflm: Support code and optimized routines for TFLM.
  • third_party: Third party repositories for Bazel.
  • toolchains: Crosscomple toolchain setup for Bazel.

Build the project


The project uses Bazel 5.1.1, to align with OpenTitan build system requirements.

bazel build //...

To run the unit tests (with the kelvin_sim ISS) Make sure the Environment variable $ROOTDIR is set to the root directory of the local repo (or run source build/

bazel test //...


TODO: Add CMake flow

Run the executable

The binaries can be simulated with the kelvin simulator, located at <dir>/sim/kelvin.

sim_kelvin <elf location>

Load the generated .bin binaries to the FPGA emulator/Renode simulator.