AI Engine Development

See Vitis™ Development Environment on xilinx.com
See Vitis-AI™ Development Environment on xilinx.com

# Window Based AI Engine Kernels with Mixed Data Types This example is similar to the previous [Window Based AI Engine Kernels](./window_based_aie_kernel.md) example, except that one AI Engine kernel has floating point interfaces and one AI Engine kernel has `cint16` interfaces. It will focus on the difference with the previous example. One difference is that because the input and output data are in integer format for the AI Engine simulator, it has to convert data between `float`/`cint16` and integer data types. See [Prepare Data for AI Engnie Simulator](#Prepare-Data-for-AI-Engnie-Simulator). Another difference is that the PS code has to take care of the input and output data types. See [PS Application and HW Emulation Flows](#PS-Application-and-HW-Emulation-Flows). The following topics are already covered in [Window Based AI Engine Kernels](./window_based_aie_kernel.md). * [Construct Graph with Packet Switching Capability](./window_based_aie_kernel.md/#Construct-Graph-with-Packet-Switching-Capability) * [Packet Format](./window_based_aie_kernel.md/#Packet-Format) * [Example PL Kernels for Packet Switching](./window_based_aie_kernel.md/#Example-PL-Kernels-for-Packet-Switching) * [Example PS code for Packet Switching](./window_based_aie_kernel.md/#Example-PS-code-for-Packet-Switching) ### Prepare Data for AI Engnie Simulator Change the working directory to `window_aie_mix_int32_float_cint16`. The graph code for this example is the same as the [Window Based AI Engine Kernels](./window_based_aie_kernel.md) example. The AI Engine kernel `core[2]` (`aie/aie_core3.cpp`) has floating point interfaces, and the AI Engine kernel `core[3]` (`aie/aie_core4.cpp`) has `cint16` interfaces. When preparing the data for the AI Engnine simulator, all values should be in 32-bit integer format. The conversion is similar to the `reinterpret_cast` operation in C++. It is done manually in any language. For example, when you want to feed float data `1.0f`, `2.0f`,..., into the AI Engine kernel, the integer format can be generated in C as shown in the following code. //input data for float for(int i=0;i<16;i++){ float tmp=i; printf("%d\n",*(int*)&tmp); } Then the data in the input file (`data/input.txt`) for float, `1.0f`,`2.0f`,...,`16.0f`, should be as follows. 0 1065353216 1073741824 1077936128 1082130432 1084227584 1086324736 1088421888 1090519040 1091567616 1092616192 1093664768 1094713344 1095761920 1096810496 1097859072 Similarly, type `cint16` should be converted to integer type. For example, for `cint16` data, {0,0},{4,4},{8,8},..., the integer format can be generated in C as shown in the following code. //input data for cint16 for(int i=0;i<16;i++){ int tmp=i*4; tmp=tmp<<16; tmp+=i*4; printf("%d\n",tmp); } Then the data in the input file (`data/input.txt`) for `cint16` data, {0,0},{4,4},{8,8},...,{60,60}, should be as follows. 0 262148 524296 786444 1048592 1310740 1572888 1835036 2097184 2359332 2621480 2883628 3145776 3407924 3670072 3932220 Take a look at the input file `data/input.txt` to see how input data is organized. Run the following make command to run the AI Engine compiler and simulator. make aiesim The output data is in `aiesimulator_output/data/output.txt`. Similarly, the output data can be converted from integer to `float` or `cint16` to be human-readable. ### PS Application and HW Emulation Flows The difference in the PS application from [Window Based AI Engine Kernels](./window_based_aie_kernel.md) is that the input buffers and output buffers for different data types should be modified accordingly. Take a look at the code in `sw/host.cpp`. Note how `float` and complex type (for `cint16`) is used in the code. // output memory xrtBufferHandle out_bo3 = xrtBOAlloc(dhdl, mem_size, 0, /*BANK=*/0); xrtBufferHandle out_bo4 = xrtBOAlloc(dhdl, mem_size, 0, /*BANK=*/0); float *host_out3 = (float*)xrtBOMap(out_bo3); std::complex *host_out4 = (std::complex*)xrtBOMap(out_bo4); // input memory xrtBufferHandle in_bo3 = xrtBOAlloc(dhdl, mem_size, 0, /*BANK=*/0); xrtBufferHandle in_bo4 = xrtBOAlloc(dhdl, mem_size, 0, /*BANK=*/0); float *host_in3 = (float*)xrtBOMap(in_bo3); std::complex *host_in4 = (std::complex*)xrtBOMap(in_bo4); Correspondingly, the pre-processing and post-processing of this data has been changed. Run HW emulation with the following make command (it builds the HW system and host application). make run_hw_emu Hint: If the keyboard is accidentally hit and stops the system booting automatically, type boot at the **Versal>** prompt to resume the system booting. After Linux has booted, run the following commands at the Linux prompt (this is only for HW cosim). mount /dev/mmcblk0p1 /mnt cd /mnt export XILINX_XRT=/usr export XCL_EMULATION_MODE=hw_emu ./host.exe a.xclbin To exit QEMU press Ctrl+A, x To run in hardware, first build the system and application using the following make command. make package TARGET=hw After Linux has booted, run the following commands at the Linux prompt. export XILINX_XRT=/usr cd /mnt/sd-mmcblk0p1 ./host.exe a.xclbin The host code is self-checking. It will check the correctness of output data. If the output data is correct, after the run has completed, it will print: TEST PASSED ### Conclusion In this step, you learned about the following concepts. * Preparing `float` and `cint16` data types for the AI Engine simulator. * PS application for different data types. Next, review [Packet Stream Based AI Engine Kernels](./pktstream_based_aie_kernel.md). Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.