zslwyuan / stencil_hls

Implementation of time and space-tiled stencil in Vivado HLS.

Building the project

This project is configured using CMake, which will generate all the build targets necessary to both simulate and run in hardware. The code depends on hlslib, which must be cloned as a submodule with git submodule update --init. The project should be configured and built out of directory, e.g.:

mkdir build 
cd build 
cmake ../ -DSTENCIL_DSA_STRING=xilinx_vcu1525_dynamic_5_1 -DSTENCIL_DIMMS=2

Apart from the target DSA (platform), and number of DIMMs shown above, important configuration variables that affect the final circuit are:

• STENCIL_DATA_TYPE
• STENCIL_TIME
• STENCIL_MEMORY_WIDTH
• STENCIL_KERNEL_WIDTH
• STENCIL_DEPTH
• STENCIL_BLOCKS
• STENCIL_ROWS
• STENCIL_COLS
• STENCIL_TARGET_CLOCK
• STENCIL_TARGET_TIMING

To build the host-side code, run make all (or just make). To build the hardware kernel, use make compile_kernel and make link_kernel. To see the expected performance numbers for the current configuration, run the executable Stats, which is also built my make all.

Running the kernel

Once the kernel has been built, it is run in hardware by executing ExecuteKernel.exe, which is built by make all. This requires an appropriate SDAccel environment to be set up, which can be done with the following shell commands:

export XILINX_OPENCL=<DSA folder>/xbinst
export PATH=$XILINX_OPENCL/runtime/bin:$PATH
unset XILINX_SDX
unset XILINX_SDACCEL
unset XCL_EMULATION_MODE

Running the kernel will print the resulting compute and memory performance.

Source code

The main kernel is located in src/Stencil.cpp, with the majority of the functionality contained in include/Compute.h and src/Memory.cpp.