Clocking - 1.1 English

DPUCVDX8G for Versal ACAPs Product Guide (PG389)
Document ID
PG389
Release Date
2022-01-20
Version
1.1 English

There are three clock domains in the DPUCVDX8G IP:

  • s_axi_aclk for register configuration.
  • m_axi_aclk for general logic control in the DPUCVDX8G PL component.
  • s00_aie_aclk for the AI Engine component.

The two input clocks on the PL component can each be configured at different frequencies independently. Generally, the s_axi_aclk is set at a lower frequency to obtain a better timing closure. Therefore, the corresponding reset for the two input clocks must be configured correctly.

The s00_aie_aclk is the output clock of the AI Engine module. This clock is output to the NoC for data transmission between the AI Engine and the NoC. The frequency of s00_aie_aclk can be set in the Vitis flow.

Clock Domains

The following figure shows the three clock domains.

Figure 1. Clock Domains in the DPUCVDX8G
s_axi_aclk
The s_axi_aclk is used for the register configuration module. This module receives the DPUCVDX8G configuration though the S_AXI_CONTROL interface. The DPU configuration registers are updated at a very low frequency and most of those registers are set at the start of a task. It is recommended to use a frequency of 100 MHz for the S-AXI clock.
m_axi_aclk
The m_axi_aclk is used for most of the logic in the PL component except for the register configuration module. The m_axi_aclk is also used for the data transmission between the DPUCVDX8G PL and the NoC. The m_axi_aclk is the associated clock for all the AXI4 master interface and AXI4-Stream interface from the PL component. The recommended frequency for this clock is 333 MHz.
s00_aie_aclk
The s00_aie_aclk (connected with the pin s00_axi_aclk of AIE IP) is the working clock for the AI Engine array, and interface between NOC. Its frequency is set by AIE_CORE_REF_CTRL_FREQMHZ in the AIE IP, and should set as four times of the frequency of m_axi_aclk (connected with the pin aclk0 of AIE IP), or the maximum AIE frequency (for example, 1.25GHz for XCV1902-2MP part on the VCK190 board). The frequency of AIE_CORE_REF_CTRL_FREQMHZ can be set in the postlink.tcl file in the Vitis flow.