AI Engine Simulation Based Power Estimation - 2021.2 English

Xilinx Power Estimator User Guide for Versal ACAP (UG1275)

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2021.2 English
You can use the simulation flow to get more accurate power analysis of the AI Engine. You can run the AI Engine simulator after the AI Engine compiler flow. Perform the following steps for simulation based power estimation of the AI Engine:
  1. Generate a vcd file while running AI Engine simulator.
  2. Use the vcdanalyze tool to create more accurate .xpe file using the following command:
    vcdanalyze --vcd <vcdfile> --xpe
    1. <vcdfile> is the generated .vcd file from the AI Engine simulator. The above command generates a new .xpe file in aiesim_xpe folder.
  3. Import the newly generated .xpe file to XPE tool for more accurate AI Engine power estimation.
    1. This .xpe file has more accurate vector load and memory R/W rate.

You need to consider the following before performing simulation based power estimation of the AI Engine:

  • Presently only vector instructions such as VMAC and VMUL are supported in this flow. Therefore, simulation flow should only be used if your design has vector instructions. If the AI Engine has scalar instructions (not the expected use of AI Engines), it is recommended to go with the compiler import flow.
  • While using the vcdanalyze utility on a vcd file, navigate to the location of the .vcd file as the work directory is also required to generate .xpe output.
  • To create a .xpe file in a specific directory, use the following command:
    vcdanalyze --vcd <vcdfile> --xpe --xpe-dir <dir_name>
    where <dir_name> is the directory name where generated .xpe file is expected.

For more information on how to generate the .vcd file and vcdanalyze tool, see Versal ACAP AI Engine Programming Environment User Guide (UG1076).