Add support for parameterized BlackBoxes

Also restrict black boxes to not allow hardware inside of them since it was
being silently dropped anyway.

Resolves #289

2 files changed, 21 insertions, 7 deletions

diff --git a/chiselFrontend/src/main/scala/chisel3/core/BlackBox.scala b/chiselFrontend/src/main/scala/chisel3/core/BlackBox.scala
index 7fe429fa..85a57111 100644
--- a/chiselFrontend/src/main/scala/chisel3/core/BlackBox.scala
+++ b/chiselFrontend/src/main/scala/chisel3/core/BlackBox.scala
@@ -3,11 +3,20 @@
 package chisel3.core
 
 import chisel3.internal.Builder.pushCommand
-import chisel3.internal.firrtl.{ModuleIO, DefInvalid}
+import chisel3.internal.firrtl._
+import chisel3.internal.throwException
 import chisel3.internal.sourceinfo.SourceInfo
 // TODO: remove this once we have CompileOptions threaded through the macro system.
 import chisel3.core.ExplicitCompileOptions.NotStrict
 
+/** Parameters for BlackBoxes */
+sealed abstract class Param
+case class IntParam(value: BigInt) extends Param
+case class DoubleParam(value: Double) extends Param
+case class StringParam(value: String) extends Param
+/** Unquoted String */
+case class RawParam(value: String) extends Param
+
 /** Defines a black box, which is a module that can be referenced from within
   * Chisel, but is not defined in the emitted Verilog. Useful for connecting
   * to RTL modules defined outside Chisel.
@@ -16,12 +25,9 @@ import chisel3.core.ExplicitCompileOptions.NotStrict
   * {{{
   * ... to be written once a spec is finalized ...
   * }}}
+  * @note The parameters API is experimental and may change
   */
-// REVIEW TODO: make Verilog parameters part of the constructor interface?
-abstract class BlackBox extends Module {
-  // Don't bother taking override_clock|reset, clock/reset locked out anyway
-  // TODO: actually implement this.
-  def setVerilogParameters(s: String): Unit = {}
+abstract class BlackBox(val params: Map[String, Param] = Map.empty[String, Param]) extends Module {
 
   // The body of a BlackBox is empty, the real logic happens in firrtl/Emitter.scala
   // Bypass standard clock, reset, io port declaration by flattening io
diff --git a/chiselFrontend/src/main/scala/chisel3/core/Module.scala b/chiselFrontend/src/main/scala/chisel3/core/Module.scala
index ca391091..62b6d5ce 100644
--- a/chiselFrontend/src/main/scala/chisel3/core/Module.scala
+++ b/chiselFrontend/src/main/scala/chisel3/core/Module.scala
@@ -41,8 +41,16 @@ object Module {
                      sourceInfo.makeMessage(" See " + _))
     }
     Builder.currentModule = parent // Back to parent!
+
     val ports = m.computePorts
-    val component = Component(m, m.name, ports, m._commands)
+    // Blackbox inherits from Module so we have to match on it first TODO fix
+    val component = m match {
+      case bb: BlackBox =>
+        DefBlackBox(bb, bb.name, ports, bb.params)
+      case mod: Module =>
+        mod._commands.prepend(DefInvalid(childSourceInfo, mod.io.ref)) // init module outputs
+        DefModule(mod, mod.name, ports, mod._commands)
+    }
     m._component = Some(component)
     Builder.components += component
     // Avoid referencing 'parent' in top module