The PHY supports DRAM additive latency. The only effect on the PHY interface due
to enabling Additive Latency (AL) in the MRS parameters is in the timing of the
wrDataEn signal after mcWrCAS assertion. The PHY
takes the AL setting into account when scheduling wrDataEn. You can
also find the rdDataEn asserts much later after
mcRdCAS because the DRAM returns data much later. The AL setting
also has an impact on whether or not the EXTRA_CMD_DELAY parameter needs to be set to a
non-zero value.