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Zynq-7000 AP SoC Technical Reference Manual www.xilinx.com 870
UG585 (v1.11) September 27, 2016
Appendix B: Register Details
Register (ddrc) ctrl_reg4
Register ctrl_reg4 Details
Register (ddrc) ctrl_reg5
Name ctrl_reg4
Relative Address 0x0000006C
Absolute Address 0xF800606C
Width 16 bits
Access Type rw
Reset Value 0x00001610
Description Controller 4
Field Name Bits Type Reset Value Description
dfi_t_ctrlupd_interval_
max_x1024
15:8 rw 0x16 This is the maximum amount of time between
Controller initiated DFI update requests. This
timer resets with each update request; when the
timer expires, traffic is blocked for a few cycles.
PHY can use this idle time to recalibrate the delay
lines to the DLLs. The DLL calibration is also used
to reset PHY FIFO pointers in case of data capture
errors. Updates are required to maintain
calibration over PVT, but frequent updates may
impact performance. Units: 1024 clocks
dfi_t_ctrlupd_interval_
min_x1024
7:0 rw 0x10 This is the minimum amount of time between
Controller initiated DFI update requests (which
will be executed whenever the controller is idle).
Set this number higher to reduce the frequency of
update requests, which can have a small impact
on the latency of the first read request when the
controller is idle. Units: 1024 clocks
Name ctrl_reg5
Relative Address 0x00000078
Absolute Address 0xF8006078
Width 32 bits
Access Type mixed
Reset Value 0x00455111
Description Controller register 5