rocket-chip/project/build.scala

import sbt._
import Keys._
//val extracted: Extracted = Project.extract(state)
//import extracted._

object BuildSettings extends Build {
  val buildOrganization = "berkeley"
  val buildVersion = "1.1"
  val buildScalaVersion = "2.9.2"

  val chiselDebug = SettingKey[Boolean]("chisel-debug", "generated backend sources with debug signals")
  val chiselArgsDebug = SettingKey[Seq[String]]("chisel-args-debug", "additional chisel args for debug backend signals")
  val chiselArgsC = SettingKey[Seq[String]]("chisel-args-c", "default chisel args for c backend")
  val chiselArgsVlsi = SettingKey[Seq[String]]("chisel-args-vlsi", "default chisel args for vlsi backend")
  val chiselArgsFpga = SettingKey[Seq[String]]("chisel-args-fpga", "default chisel args for fpga backend")

  val buildSettings = Defaults.defaultSettings ++ Seq (
    //unmanagedBase <<= baseDirectory { base => base / ".." / custom_lib" },
    organization := buildOrganization,
    version      := buildVersion,
    scalaVersion := buildScalaVersion,
    chiselDebug     := false,
    chiselArgsDebug := Seq("--debug","--vcd"),
    chiselArgsC     := "--targetDir ../emulator/generated-src --backend c".split(" "),
    chiselArgsFpga  := "--targetDir ../fpga/generated-src --backend fpga".split(" "),
    chiselArgsVlsi  := "--targetDir ../vlsi/generated-src --backend v".split(" ")
  )

  lazy val chisel = Project("chisel", file("chisel"), settings = buildSettings)
  lazy val hardfloat = Project("hardfloat", file("hardfloat"), settings = buildSettings) dependsOn(chisel)
  lazy val hwacha = Project("hwacha", file("hwacha"), settings = buildSettings) dependsOn(hardfloat,chisel)
  lazy val uncore = Project("uncore", file("uncore"), settings = buildSettings) dependsOn(chisel)
  lazy val rocket = Project("rocket", file("rocket"), settings = buildSettings) dependsOn(uncore,hwacha,hardfloat,chisel)
  lazy val referencechip = Project("referencechip", file("referencechip"), settings = buildSettings ++ chipSettings) dependsOn(chisel,rocket)

  val elaborateTask = InputKey[Unit]("elaborate", "convert chisel components into backend source code")
  val makeTask = InputKey[Unit]("make", "trigger backend-specific makefile command")

  val chipSettings = Seq(
    elaborateTask <<= inputTask { (argTask: TaskKey[Seq[String]]) =>
      (argTask, fullClasspath in Runtime, thisProject, chiselDebug, chiselArgsDebug) map {
        (args: Seq[String], cp: Classpath, pr: ResolvedProject, debug: Boolean, debugArgs: Seq[String]) => { 
          val numArgs = 1
          require(args.length >= numArgs, "syntax: elaborate <component> [chisel args]")
          val projectName = pr.id
          val packageName = projectName //TODO: valid convention?
          val componentName = args(0)
          val optionalArgs = if(debug) debugArgs else Nil
          val classLoader = new java.net.URLClassLoader(cp.map(_.data.toURL).toArray, cp.getClass.getClassLoader)
          val chiselMainClass = classLoader.loadClass("Chisel.chiselMain$")
          val chiselMainObject = chiselMainClass.getDeclaredFields.head.get(null)
          val chiselMain = chiselMainClass.getMethod("run", classOf[Array[String]], classOf[Function0[_]])
          val chiselArgs = args.drop(numArgs) ++ optionalArgs
          val component = classLoader.loadClass(packageName+"."+componentName)
          val generator = () => component.newInstance()
          chiselMain.invoke(chiselMainObject, Array(chiselArgs.toArray, generator):_*)
        }
      }
    },
    makeTask <<= inputTask { (argTask: TaskKey[Seq[String]]) =>
      (argTask) map {
        (args: Seq[String]) => { 
          require(args.length >= 2, "syntax: <dir> <target>")
          val makeDir = args(0)
          val target = args(1)
          val jobs = java.lang.Runtime.getRuntime.availableProcessors
          val make = "make -C" + makeDir + " -j" + jobs + " " + target
          make!
        }
      }
    }
  )
  
}