ddrdqclk
Contains settings that control clock ddr_dq_clk generated from the C2 output of the SDRAM PLL.
Fields are only reset by a cold reset.
Module Instance | Base Address | Register Address |
---|---|---|
clkmgr | 0xFFD04000 | 0xFFD040D0 |
Offset: 0xD0
Access: RW
Important: To prevent indeterminate
system behavior, reserved areas of memory must not be accessed by software or
hardware. Any area of the memory map that is not explicitly defined as a register
space or accessible memory is considered reserved.
Bit Fields | |||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 |
Reserved |
phase RW 0x0 |
||||||||||||||
15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
phase RW 0x0 |
cnt RW 0x1 |
ddrdqclk Fields
Bit | Name | Description | Access | Reset |
---|---|---|---|---|
20:9 | phase | Increment the phase of the VCO output by the value in this field multiplied by 45 degrees. The accumulated phase shift is the total shifted amount since the last assertion of the 'SDRAM All Output Divider Reset' bit in the SDRAM vco control register. In order to guarantee the phase shift to a known value, 'SDRAM clocks output phase align' bit should be asserted before programming this field. This field is only writeable by SW when it is zero. HW updates this field in real time as the phase adjustment is being made. SW may poll this field waiting for zero indicating the phase adjustment has completed by HW. |
RW | 0x0 |
8:0 | cnt | Divides the VCO frequency by the value+1 in this field. |
RW | 0x1 |