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Ixiasoft
Visible to Intel only — GUID: nik1410564990470
Ixiasoft
10.4. SDC Timing Constraints
Ignored filter at altpcied_sv.sdc(25): *reconfig_xcvr_clk* could not be matched with a port or pin or register or keeper or net
SDC Timing Constraints Required for the Stratix V Hard IP for PCIe and Design Example
# Constraints required for the Hard IP for PCI Express
# derive_pll_clock is used to calculate all clock derived from
# PCIe refclk. It must be applied once across all of the SDC
# files used in a project
create_clock -period "100 MHz" -name {refclk_clk} {*refclk_clk*}
derive_pll_clocks -create_base_clocks
derive_clock_uncertainty
#########################################################################
# Reconfig Controller IP core constraints
# Set reconfig_xcvr clock:
# this line will likely need to be modified to match the actual
# clock pin name used for this clock, and also changed to have
# the correct period set for the clock actually used
create_clock -period "125 MHz" -name {reconfig_xcvr_clk}
{*reconfig_xcvr_clk*}
######################################################################
# Hard IP testin pins SDC constraints
set_false_path -from [get_pins -compatibility_mode *hip_ctrl*]
######################################################################
# These additional constraints are for Gen3 only
set_false_path -from [get_clocks {reconfig_xcvr_clk}] -to [get_clocks
{*|altpcie_hip_256_pipen1b|stratixv_hssi_gen3_pcie_hip|coreclkout}]
set_false_path -from [get_clocks {*|altpcie_hip_256_pipen1b|
stratixv_hssi_gen3_pcie_hip|coreclkout}] -to
[get_clocks {reconfig_xcvr_clk}]
Additional .sdc timing are in the /<project_dir>/synthesis/submodules directory.
SDC Constraints for the Hard IP for PCIe
In the example above, you should only apply the first three constraints, in one location across all of the SDC files in your project. Differences between Fitter timing analysis and TimeQuest timing analysis arise if these constraints are applied multiple times.
SDC Constraints for the Qsys Example Design
The .sdc file includes constraints for the Transceiver Reconfiguration Controller IP Core which is included in the Qsys example designs. You may need to change the frequency and actual clock pin name to match your design. The .sdc file also specifies some false timing paths for Transceiver Reconfiguration Controller and Transceiver PHY Reset Controller IP Cores. Be sure to include these constraints in your .sdc file.