The input clock frequency of the axi_clkgen was changed from 200 MHz to
100 Mhz. Update the divider settings accordingly to keep the standard
default output frequency of 148.5 MHz.
The incorrect divider settings did not affect operation of the design since
software reprograms them at startup anyway, but changing them avoids the
following warning:
[DRC 23-20] Rule violation (AVAL-46) v7v8_mmcm_fvco_rule1 - The current computed target frequency, FVCO, is out of range for cell i_system_wrapper/system_i/axi_hdmi_clkgen/inst/i_mmcm_drp/i_mmcm. The computed FVCO is 445.455 MHz. The valid FVCO range for speed grade -1 is 600MHz to 1200MHz. The cell attribute values used to compute FVCO are CLKFBOUT_MULT_F = 49.000, CLKIN1_PERIOD = 10.00000, and DIVCLK_DIVIDE = 11 (FVCO = 1000 * CLKFBOUT_MULT_F/(CLKIN1_PERIOD * DIVCLK_DIVIDE)).
This violation may be corrected by:
1. The timer uses timing constraints for clock period or clock frequency that affect CLKIN1 to set cell attribute CLKIN1_PERIOD, over-riding any previous value. This may already be in place and, if so this violation will be resolved once Timing is run. Otherwise, consider modifying timing constraints to adjust the CLKIN1_PERIOD and bring FVCO into the allowed range.
2. In the absence of timing constraints that affect CLKIN1, consider modifying the cell CLKIN1_PERIOD to bring FVCO into the allowed range.
3. If CLKIN1_PERIOD is satisfactory, modify the CLKFBOUT_MULT_F or DIVCLK_DIVIDE cell attributes to bring FVCO into the allowed range.
4. The MMCM configuration may be dynamically modified by use of DRP which is recognized by an ACTIVE signal on DCLK pin.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
For the M2K standalone version we run the interface clock at a lower rate
to reduce the power consumption. While this is not necessary on the ZED
board we also run the interface at a lower rate for consistency.
Currently the video DMA on the ZED board uses the interface clock for the
data path as well. This is now too slow to support 1080p@60Hz so move it
over to a faster clock.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Lars-Peter Clausen
Adrian Costina