vendor.lattice_ecp5: fix sdc generation

Author: anuejn

nmigen/vendor/lattice_ecp5.py

@@ -237,11 +237,12 @@ class LatticeECP5Platform(TemplatedPlatform):
             {{get_override("add_preferences")|default("# (add_preferences placeholder)")}}
         """,
         "{{name}}.sdc": r"""
+            set_hierarchy_separator {/}
             {% for net_signal, port_signal, frequency in platform.iter_clock_constraints() -%}
                 {% if port_signal is not none -%}
-                    create_clock -name {{port_signal.name|tcl_escape}} -period {{1000000000/frequency}} [get_ports {{port_signal.name|tcl_escape}}]
+                    create_clock -name {{port_signal.name|tcl_quote}} -period {{1000000000/frequency}} [get_ports {{port_signal.name|tcl_quote}}]
                 {% else -%}
-                    create_clock -name {{net_signal.name|tcl_escape}} -period {{1000000000/frequency}} [get_nets {{net_signal|hierarchy("/")|tcl_escape}}]
+                    create_clock -name {{net_signal.name|tcl_quote}} -period {{1000000000/frequency}} [get_nets {{net_signal|hierarchy("/")|tcl_quote}}]
                 {% endif %}
             {% endfor %}
             {{get_override("add_constraints")|default("# (add_constraints placeholder)")}}