Merge pull request #2938 from rslawson/add-nix-flake

Add Nix flake to ORFS.

Author: maliberty

flake.lock

@@ -0,0 +1,42 @@
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+    openroad = {
+      type = "git";
+      url = "https://github.com/The-OpenROAD-Project/OpenROAD";
+      submodules = true;
+      rev = "ec1bf1a13902813b722f8341c432cd09714d9e55";
+    };
+    yosys = {
+      type = "git";
+      url = "https://github.com/The-OpenROAD-Project/yosys";
+      submodules = true;
+      rev = "c4b5190229616f7ebf8197f43990b4429de3e420";
+    };
+  };
+  outputs = { self, nixpkgs, flake-utils, openroad, yosys }: flake-utils.lib.eachDefaultSystem (
+    system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+      in {
+      devShells.default = pkgs.mkShell {
+        buildInputs = [
+          openroad.packages.${system}.default
+          yosys.packages.${system}.default
+          pkgs.time
+          pkgs.klayout
+          pkgs.verilator
+          pkgs.perl
+          pkgs.python3
+          pkgs.python3Packages.pandas
+          pkgs.python3Packages.numpy
+          pkgs.python3Packages.firebase-admin
+          pkgs.python3Packages.click
+          pkgs.python3Packages.pyyaml
+          pkgs.python3Packages.yamlfix
+        ];
+      };
+    }
+  );
+}

flake.nix

@@ -227,15 +227,27 @@ endif
 # Priority is given to
 #       1 user explicit set with variable in Makefile or command line, for instance setting OPENROAD_EXE
 #       2 ORFS compiled tools: openroad, yosys
-export OPENROAD_EXE      ?= $(abspath $(FLOW_HOME)/../tools/install/OpenROAD/bin/openroad)
-export OPENSTA_EXE       ?= $(abspath $(FLOW_HOME)/../tools/install/OpenROAD/bin/sta)
+ifneq (${IN_NIX_SHELL},)
+  export OPENROAD_EXE := $(shell command -v openroad)
+else
+  export OPENROAD_EXE ?= $(abspath $(FLOW_HOME)/../tools/install/OpenROAD/bin/openroad)
+endif
+ifneq (${IN_NIX_SHELL},)
+  export OPENSTA_EXE := $(shell command -v sta)
+else
+  export OPENSTA_EXE ?= $(abspath $(FLOW_HOME)/../tools/install/OpenROAD/bin/sta)
+endif
 
 OPENROAD_ARGS            = -no_init -threads $(NUM_CORES) $(OR_ARGS)
 OPENROAD_CMD             = $(OPENROAD_EXE) -exit $(OPENROAD_ARGS)
 OPENROAD_NO_EXIT_CMD     = $(OPENROAD_EXE) $(OPENROAD_ARGS)
 OPENROAD_GUI_CMD         = $(OPENROAD_EXE) -gui $(OR_ARGS)
 
-YOSYS_EXE               ?= $(abspath $(FLOW_HOME)/../tools/install/yosys/bin/yosys)
+ifneq (${IN_NIX_SHELL},)
+  YOSYS_EXE := $(shell command -v yosys)
+else
+  YOSYS_EXE ?= $(abspath $(FLOW_HOME)/../tools/install/yosys/bin/yosys)
+endif
 
 # Use locally installed and built klayout if it exists, otherwise use klayout in path
 KLAYOUT_DIR = $(abspath $(FLOW_HOME)/../tools/install/klayout/)