build/lattice/radiant: allow use of Windows-side (.exe) radiant toolchain under WSL2

litex/build/lattice/radiant.py

@@ -209,6 +209,10 @@ class LatticeRadiantToolchain(GenericToolchain):
         if self._synth_mode == "yosys":
             script_contents += self._yosys.get_yosys_call(target="script") + "\n"
 
+        # Radiant installed on Windows, executed from WSL2
+        if "microsoft-standard" in uname().release and which("pnmainc.exe") is not None:
+            tool = "pnmainc.exe"
+
         script_contents += "{tool} {tcl_script}{fail_stmt}\n".format(
             tool = tool,
             tcl_script = self._build_name + ".tcl",
@@ -232,6 +236,10 @@ class LatticeRadiantToolchain(GenericToolchain):
             shell = ["bash"]
             tool  = "radiantc"
 
+        # Radiant installed on Windows, executed from WSL2
+        if "microsoft-standard" in uname().release and which("pnmainc.exe") is not None:
+            tool = "pnmainc.exe"
+
         if which(tool) is None:
             msg = "Unable to find Radiant toolchain, please:\n"
             msg += "- Add Radiant toolchain to your $PATH."