sayma_amc: add period constraint on self.crg.cd_sys.clk

sbourdeauducq · sbourdeauducq · commit c092887f6e01 · 2017-08-21T17:36:52.000-04:00
diff --git a/misoc/targets/sayma_amc.py b/misoc/targets/sayma_amc.py
@@ -78,6 +78,8 @@ def __init__(self, sdram="ddram_64", sdram_controller_type="minicon", **kwargs):
                           **kwargs)
 
         self.submodules.crg = _CRG(platform)
+        self.crg.cd_sys.clk.attr.add("keep")
+        platform.add_period_constraint(self.crg.cd_sys.clk, 8.0)
 
         self.submodules.ddrphy = kusddrphy.KUSDDRPHY(platform.request(sdram))
         self.config["KUSDDRPHY"] = None
