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[/] [openrisc/] [trunk/] [orpsocv2/] [boards/] [xilinx/] [atlys/] [rtl/] - Rev 854

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854 Add OR1200_OR32_LWS define to board specific or1200_defines.v stekern 4177d 16h /openrisc/trunk/orpsocv2/boards/xilinx/atlys/rtl/
677 atlys: add 2-clock synchronizer chain for ddr2_calib_done

The signal ddr2_calib_done signal comes from the ddr2 clock domain,
while wb_req is treating it as if it came from wb_clk domain. As a
result the timing analysis tool assumed a worst case scenario of 5ns
between the two domains and the results were miserable.

While we can argue that this is a multi-cycle path, the fact is that
ddr2_calib_done feeds into multiple logic sinks and can potentially
cause meta-stability issue in the design. The solution is to add a
2-clock meta-stability filter to address both the timing problems and
the meta-stability concern.

Signed-off-by: Jason Zheng <jxzheng@gmail.com>
Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Acked-by: Olof Kindgren <olof.kindgren@orsoc.se>
stekern 4464d 05h /openrisc/trunk/orpsocv2/boards/xilinx/atlys/rtl/
627 orpsoc: add Digilent Atlys spartan6 board rtl

Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
stekern 4645d 17h /openrisc/trunk/orpsocv2/boards/xilinx/atlys/rtl/

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