Variable Precision DSP Blocks User Guide: Agilex™ 5 FPGAs and SoCs

ID 813968
Date 4/01/2024
Public
Document Table of Contents

3.3.3. Tensor Accumulation Mode

In Tensor accumulation mode, two columns of 64-bit input data are fed through port fp32_a{1..2} to perform addition or subtraction with the 32-bit floating-point values from the previous DSP block through cascade_data_in[63:0] by accumulator (FP32 ALU).

To perform addition or subtraction on accumulator, set the parameter dsp_fp32_sub_encorrespondingly based on the parameter table. To enable cascading connection from previous DSP block, enable the parameter dsp_chain_tensor in the settings.

The two 32-bit floating-point results are sent out through fp32_a{1..2} on first and second column or it can be cascaded to the next DSP block through cascade_data_out[63:0].

Table 29.  Tensor Accumulation Mode Equations
Accumulator Operation Cascade Input Data Enabled
Addition

Column One = fp32_a1[31:0] + cascade_data_in_col_1[31:0]

Column Two = fp32_a2[31:0] + cascade_data_in_col_2[31:0]

Subtraction

Column One = fp32_a1[31:0] - cascade_data_in_col_1[31:0]

Column Two = fp32_a2[31:0] - cascade_data_in_col_2[31:0]

Figure 56. Tensor Accumulation Mode One Column Datapath