Fix mill source layout and bump Chisel

.scalafmt.conf

@@ -1,28 +1,20 @@
-version = 2.6.4
+version = "3.7.15"
+runner.dialect = scala213
 
 maxColumn = 120
-align = most
-continuationIndent.defnSite = 2
+align.preset = most
+indent.defnSite = 2
 assumeStandardLibraryStripMargin = true
-docstrings = ScalaDoc
+docstrings.style = SpaceAsterisk
 lineEndings = preserve
 includeCurlyBraceInSelectChains = false
-danglingParentheses = true
+danglingParentheses.preset = true
 
-align.tokens.add = [
-  {
-    code = ":"
-  },
-  {
-    code = ":="
-  },
-  {
-    code = "="
-  }
-
-]
+align.tokens."+" = [{
+code = ":"
+}]
 
-newlines.alwaysBeforeCurlyBraceLambdaParams = false
+newlines.beforeCurlyLambdaParams = "never"
 newlines.alwaysBeforeMultilineDef = false
 newlines.implicitParamListModifierForce = [before]
 

build.sc

@@ -8,39 +8,32 @@ import mill.scalalib._
 // support BSP
 import mill.bsp._
 
-object playground extends SbtModule with ScalafmtModule { m =>
-  val useChisel3 = false
-  override def millSourcePath = os.pwd / "src"
-  override def scalaVersion = if (useChisel3) "2.13.10" else "2.13.14"
+object playground extends ScalaModule with ScalafmtModule { m =>
+  override def scalaVersion = "2.13.15"
+
   override def scalacOptions = Seq(
     "-language:reflectiveCalls",
     "-deprecation",
     "-feature",
     "-Xcheckinit"
   )
-  override def sources = T.sources {
-    super.sources() ++ Seq(PathRef(millSourcePath / "main"))
-  }
-  override def ivyDeps = Agg(
-    if (useChisel3) ivy"edu.berkeley.cs::chisel3:3.6.0" else
-    ivy"org.chipsalliance::chisel:6.4.0"
-  )
-  override def scalacPluginIvyDeps = Agg(
-    if (useChisel3) ivy"edu.berkeley.cs:::chisel3-plugin:3.6.0" else
-    ivy"org.chipsalliance:::chisel-plugin:6.4.0"
-  )
-  object test extends SbtModuleTests with TestModule.ScalaTest with ScalafmtModule {
-    override def sources = T.sources {
-      super.sources() ++ Seq(PathRef(this.millSourcePath / "test"))
-    }
-    override def ivyDeps = super.ivyDeps() ++ Agg(
-      if (useChisel3) ivy"edu.berkeley.cs::chiseltest:0.6.0" else
+
+  override def ivyDeps             = Agg(ivy"org.chipsalliance::chisel:6.6.0")
+  override def scalacPluginIvyDeps = Agg(ivy"org.chipsalliance:::chisel-plugin:6.6.0")
+
+  object test extends ScalaTests with TestModule.ScalaTest with ScalafmtModule {
+    override def ivyDeps = m.ivyDeps() ++ Agg(
+      ivy"org.scalatest::scalatest::3.2.19",
+      // for formal flow in future
       ivy"edu.berkeley.cs::chiseltest:6.0.0"
     )
   }
-  def repositoriesTask = T.task { Seq(
-    coursier.MavenRepository("https://repo.scala-sbt.org/scalasbt/maven-releases"),
-    coursier.MavenRepository("https://oss.sonatype.org/content/repositories/releases"),
-    coursier.MavenRepository("https://oss.sonatype.org/content/repositories/snapshots"),
-  ) ++ super.repositoriesTask() }
+
+  def repositoriesTask = T.task {
+    Seq(
+      coursier.MavenRepository("https://repo.scala-sbt.org/scalasbt/maven-releases"),
+      coursier.MavenRepository("https://oss.sonatype.org/content/repositories/releases"),
+      coursier.MavenRepository("https://oss.sonatype.org/content/repositories/snapshots")
+    ) ++ super.repositoriesTask()
+  }
 }

src/main/DecoupledGCD.scala → playground/src/DecoupledGCD.scala

@@ -14,12 +14,9 @@ class GcdOutputBundle(val w: Int) extends Bundle {
   val gcd    = UInt(w.W)
 }
 
-/**
-  * Compute Gcd using subtraction method.
-  * Subtracts the smaller from the larger until register y is zero.
-  * value input register x is then the Gcd.
-  * Unless first input is zero then the Gcd is y.
-  * Can handle stalls on the producer or consumer side
+/** Compute Gcd using subtraction method. Subtracts the smaller from the larger until register y is zero. value input
+  * register x is then the Gcd. Unless first input is zero then the Gcd is y. Can handle stalls on the producer or
+  * consumer side
   */
 class DecoupledGcd(width: Int) extends Module {
   val input  = IO(Flipped(Decoupled(new GcdInputBundle(width))))

playground/src/Elaborate.scala

@@ -0,0 +1,12 @@
+object Elaborate extends App {
+  val firtoolOptions = Array(
+    "--lowering-options=" + List(
+      // make yosys happy
+      // see https://github.com/llvm/circt/blob/main/docs/VerilogGeneration.md
+      "disallowLocalVariables",
+      "disallowPackedArrays",
+      "locationInfoStyle=wrapInAtSquareBracket"
+    ).reduce(_ + "," + _)
+  )
+  circt.stage.ChiselStage.emitSystemVerilogFile(new gcd.GCD(), args, firtoolOptions)
+}

src/main/GCD.scala → playground/src/GCD.scala

@@ -2,10 +2,8 @@ package gcd
 
 import chisel3._
 
-/**
-  * Compute GCD using subtraction method.
-  * Subtracts the smaller from the larger until register y is zero.
-  * value in register x is then the GCD
+/** Compute GCD using subtraction method. Subtracts the smaller from the larger until register y is zero. value in
+  * register x is then the GCD
   */
 class GCD extends Module {
   val io = IO(new Bundle {

src/test/GCDSpec.scala → playground/test/src/GCDSpec.scala

@@ -8,9 +8,7 @@ import chisel3.simulator.EphemeralSimulator._
 import org.scalatest.freespec.AnyFreeSpec
 import org.scalatest.matchers.must.Matchers
 
-/**
-  * This is a trivial example of how to run this Specification
-  * From within sbt use:
+/** This is a trivial example of how to run this Specification From within sbt use:
   * {{{
   * testOnly gcd.GCDSpec
   * }}}
@@ -26,9 +24,12 @@ import org.scalatest.matchers.must.Matchers
 class GCDSpec extends AnyFreeSpec with Matchers {
   "Gcd should calculate proper greatest common denominator" in {
     simulate(new DecoupledGcd(16)) { dut =>
-      val testValues = for { x <- 0 to 10; y <- 0 to 10} yield (x, y)
-      val inputSeq = testValues.map { case (x, y) => (new GcdInputBundle(16)).Lit(_.value1 -> x.U, _.value2 -> y.U) }
-      val resultSeq = testValues.map { case (x, y) =>
+      val testValues = for {
+        x <- 0 to 10
+        y <- 0 to 10
+      } yield (x, y)
+      val inputSeq   = testValues.map { case (x, y) => (new GcdInputBundle(16)).Lit(_.value1 -> x.U, _.value2 -> y.U) }
+      val resultSeq  = testValues.map { case (x, y) =>
         (new GcdOutputBundle(16)).Lit(_.value1 -> x.U, _.value2 -> y.U, _.gcd -> BigInt(x).gcd(BigInt(y)).U)
       }