As seen in Figure 6 of DS322, Qdpo_clk drives DPRa Reg out, as well as DPO. Qdpo_clk is only implemented when output registers are enabled. If this option is deselected, qdpo_clk is not implemented and DPRa Reg is driven by CLK
DPRa Reg should be clocked by QDPO_CLK when Dual Port Address input registers are used. Currently, DPRa Reg is clocked by CLK unless Output Registers are used. CR# 440076 has been filed on this issue to have DPRa Reg clocked by QDPO_CLK regardless of whether output registers are implemented.