Starting from Quartus® II software version 12.0, when you generate a Common Public Radio Interface(CPRI) IP in your design, an “altera_cpri.sdc” file is generated automatically.
It contains the set_false_path constraints as below:
set_false_path -from * -to *sync
set_false_path -from * -to *sync[*]
set_false_path -from * -to *sync1
set_false_path -from * -to *sync1[*]
set_false_path -from * -to *s0
set_false_path -from * -to *s0[*]
As is without modification, all equivalent destination names in your project will be specified with set_false_path incorrectly.
To ensure the SDC constraints are only applied on the CPRI related instances, you must modify the Synopsys Design Constraint (.sdc) file manually by inserting the CPRI instance name used in your project. For example:
set_false_path -from * -to *<your instance name>*sync
set_false_path -from * -to *<your instance name>*sync[*]
set_false_path -from * -to *<your instance name>*sync1
For further details regarding this issue, please refer to "Appendex F.Integrating the CPRI IP Core Timing Constraints in the Full Design" in CPRI MegaCore Function User Guide