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Zynq-7000 AP SoC Technical Reference Manual www.xilinx.com 869
UG585 (v1.11) September 27, 2016
Appendix B: Register Details
Register (ddrc) ctrl_reg3
Register ctrl_reg3 Details
reg_ddrc_go2critical_h
ysteresis
12:5 rw 0x0 Describes the number of cycles that
co_gs_go2critical_rd or co_gs_go2critical_wr
must be asserted before the corresponding queue
moves to the 'critical' state in the DDRC. The
arbiter controls the co_gs_go2critical_* signals; it
is designed for use with this hysteresis field set to
0.
reserved 4:0 ro 0x0 Reserved
Name ctrl_reg3
Relative Address 0x00000068
Absolute Address 0xF8006068
Width 26 bits
Access Type rw
Reset Value 0x00284027
Description Controller 3
Field Name Bits Type Reset Value Description
Field Name Bits Type Reset Value Description
reg_ddrc_dfi_t_wlmrd 25:16 rw 0x28 DDR2 and LPDDR2: not applicable.
DDR3: First DQS/DQS# rising edge after write
leveling mode is programmed. This is same as the
tMLRD value from the DRAM spec.
reg_ddrc_rdlvl_rr 15:8 rw 0x40 DDR2 and LPDDR2: not applicable.
DDR3: Read leveling read-to-read delay. Specifies
the minimum number of clock cycles from the
assertion of a read command to the next read
command.
Only applicable when connecting to PHYs
operating in PHY RdLvl Evaluation mode.
reg_ddrc_wrlvl_ww 7:0 rw 0x27 DDR2: not applicable.
LPDDR2 and DDR3: Write leveling write-to-write
delay. Specifies the minimum number of clock
cycles from the assertion of a
ddrc_dfi_wrlvl_strobe signal to the next
ddrc_dfi_wrlvl_strobe signal. Only applicable
when connecting to PHYs operating in PHY
RdLvl Evaluation mode.
Recommended value is: (RL +
reg_phy_rdc_we_to_re_delay + 50)