vivado: permit resources without pins

This is required if the LOC is done by another, external constraints set,
as in the case of the Zynq Processing System Instance.

diff --git a/mibuild/xilinx/vivado.py b/mibuild/xilinx/vivado.py
index 49747179926623618ad279d72613cc1567897d24..418ec2b3504b8d61d912bd1683d7a9bcc9996e0d 100644 (file)
--- a/mibuild/xilinx/vivado.py
+++ b/mibuild/xilinx/vivado.py
@@ -19,9 +19,11 @@ def _format_constraint(c):
                return "set_property DRIVE " + str(c.strength)
        elif isinstance(c, Misc):
                return "set_property " + c.misc.replace("=", " ")
+       else:
+               raise ValueError("unknown constraint %s" % c)
 
-def _format_xdc(signame, pin, others, resname):
-       fmt_c = [_format_constraint(c) for c in ([Pins(pin)] + others)]
+def _format_xdc(signame, resname, *constraints):
+       fmt_c = [_format_constraint(c) for c in constraints]
        fmt_r = resname[0] + ":" + str(resname[1])
        if resname[2] is not None:
                fmt_r += "." + resname[2]
@@ -35,9 +37,11 @@ def _build_xdc(named_sc, named_pc):
        for sig, pins, others, resname in named_sc:
                if len(pins) > 1:
                        for i, p in enumerate(pins):
-                               r += _format_xdc(sig + "[" + str(i) + "]", p, others, resname)
+                               r += _format_xdc(sig + "[" + str(i) + "]", resname, Pins(p), *others)
+               elif pins:
+                       r += _format_xdc(sig, resname, Pins(pins[0]), *others)
                else:
-                       r += _format_xdc(sig, pins[0], others, resname)
+                       r += _format_xdc(sig, resname, *others)
        if named_pc:
                r += "\n" + "\n\n".join(named_pc)
        return r