Xilinx / Vitis_Libraries

Vitis Libraries
https://docs.xilinx.com/r/en-US/Vitis_Libraries
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Cosim of FFT results in very large latency #125

Open bigglasses93 opened 2 years ago

bigglasses93 commented 2 years ago

Hello, I am using Vitis 2021.1 to synthesize the L1 FFT examples in latest release (2021.2 Update 1). However, during the synthesis I saw many warnings about deprecated pragmas (HLS RESOURCE). And when I ran Cosim for 1DFFT (1Dfloat_impulse) and 2DFFT (2Dfloat_impulse), I got large cycles# for the interval in simulation report. For instance, with the example of 16x16 2DFFT, I got ~4000 cycles for latency and ~2000 cycles for interval, which is far different from the reported results at https://xilinx.github.io/Vitis_Libraries/dsp/2020.1/user_guide/L1_2dfft.html#d-floating-point-fp32-fft. Which Vivado version with which release of this library should I run to get the small cycles# as reported above?