uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

pkgs/development/embedded/fpga/icestorm/default.nix

@@ -0,0 +1,70 @@
+{ lib, stdenv, fetchFromGitHub
+, pkg-config, libftdi1
+, python3, pypy3
+
+# PyPy yields large improvements in build time and runtime performance, and
+# IceStorm isn't intended to be used as a library other than by the nextpnr
+# build process (which is also sped up by using PyPy), so we use it by default.
+# See 18839e1 for more details.
+#
+# FIXME(aseipp, 3/1/2021): pypy seems a bit busted since stdenv upgrade to gcc
+# 10/binutils 2.34, so short-circuit this for now in passthru below (done so
+# that downstream overrides can't re-enable pypy and break their build somehow)
+, usePyPy ? stdenv.hostPlatform.system == "x86_64-linux"
+}:
+
+stdenv.mkDerivation rec {
+  pname = "icestorm";
+  version = "2020.12.04";
+
+  passthru = rec {
+    pythonPkg = if (false && usePyPy) then pypy3 else python3;
+    pythonInterp = pythonPkg.interpreter;
+  };
+
+  src = fetchFromGitHub {
+    owner  = "YosysHQ";
+    repo   = "icestorm";
+    rev    = "7afc64b480212c9ac2ce7cb1622731a69a7d212c";
+    sha256 = "0vxhqs2fampglg3xlfwb35229iv96kvlwp1gyxrdrmlpznhkqdrk";
+  };
+
+  nativeBuildInputs = [ pkg-config ];
+  buildInputs = [ passthru.pythonPkg libftdi1 ];
+  makeFlags = [ "PREFIX=$(out)" ];
+
+  enableParallelBuilding = true;
+
+  # fix icebox_vlog chipdb path. icestorm issue:
+  #   https://github.com/cliffordwolf/icestorm/issues/125
+  #
+  # also, fix up the path to the chosen Python interpreter. for pypy-compatible
+  # platforms, it offers significant performance improvements.
+  patchPhase = ''
+    substituteInPlace ./icebox/icebox_vlog.py \
+      --replace /usr/local/share "$out/share"
+
+    for x in icefuzz/Makefile icebox/Makefile icetime/Makefile; do
+      substituteInPlace "$x" --replace python3 "${passthru.pythonInterp}"
+    done
+
+    for x in $(find . -type f -iname '*.py'); do
+      substituteInPlace "$x" \
+        --replace '/usr/bin/env python3' '${passthru.pythonInterp}'
+    done
+  '';
+
+  meta = {
+    description = "Documentation and tools for Lattice iCE40 FPGAs";
+    longDescription = ''
+      Project IceStorm aims at reverse engineering and
+      documenting the bitstream format of Lattice iCE40
+      FPGAs and providing simple tools for analyzing and
+      creating bitstream files.
+    '';
+    homepage    = "https://github.com/YosysHQ/icestorm/";
+    license     = lib.licenses.isc;
+    maintainers = with lib.maintainers; [ shell thoughtpolice emily ];
+    platforms   = lib.platforms.all;
+  };
+}