diplomacy: a type of connect that always disables monitors (#828)

src/main/scala/diplomacy/Nodes.scala

@@ -18,7 +18,8 @@ trait InwardNodeImp[DI, UI, EI, BI <: Data]
   def bundleI(ei: EI): BI
   def colour: String
   def reverse: Boolean = false
-  def connect(edges: () => Seq[EI], bundles: () => Seq[(BI, BI)])(implicit p: Parameters, sourceInfo: SourceInfo): (Option[MonitorBase], () => Unit) = {
+  def connect(edges: () => Seq[EI], bundles: () => Seq[(BI, BI)], enableMonitoring: Boolean)
+              (implicit p: Parameters, sourceInfo: SourceInfo): (Option[MonitorBase], () => Unit) = {
     (None, () => bundles().foreach { case (i, o) => i <> o })
   }
 
@@ -229,7 +230,8 @@ abstract class MixedNode[DI, UI, EI, BI <: Data, DO, UO, EO, BO <: Data](
   lazy val bundleIn  = wireI(flipI(HeterogeneousBag(edgesIn .map(inner.bundleI(_)))))
 
   // connects the outward part of a node with the inward part of this node
-  private def bind(h: OutwardNodeHandle[DI, UI, BI], binding: NodeBinding)(implicit p: Parameters, sourceInfo: SourceInfo): Option[MonitorBase] = {
+  private def bind(h: OutwardNodeHandle[DI, UI, BI], binding: NodeBinding, enableMonitoring: Boolean)
+                  (implicit p: Parameters, sourceInfo: SourceInfo): Option[MonitorBase] = {
     val x = this // x := y
     val y = h.outward
     val info = sourceLine(sourceInfo, " at ", "")
@@ -255,14 +257,16 @@ abstract class MixedNode[DI, UI, EI, BI <: Data, DO, UO, EO, BO <: Data](
         (x.bundleIn(iStart+j), y.bundleOut(oStart+j))
       }
     }
-    val (out, newbinding) = inner.connect(edges _, bundles _)
+    val (out, newbinding) = inner.connect(edges _, bundles _, enableMonitoring)
     LazyModule.stack.head.bindings = newbinding :: LazyModule.stack.head.bindings
     out
   }
 
-  override def :=  (h: OutwardNodeHandle[DI, UI, BI])(implicit p: Parameters, sourceInfo: SourceInfo): Option[MonitorBase] = bind(h, BIND_ONCE)
+  override def :=  (h: OutwardNodeHandle[DI, UI, BI])(implicit p: Parameters, sourceInfo: SourceInfo): Option[MonitorBase] = bind(h, BIND_ONCE, true)
-  override def :*= (h: OutwardNodeHandle[DI, UI, BI])(implicit p: Parameters, sourceInfo: SourceInfo): Option[MonitorBase] = bind(h, BIND_STAR)
+  override def :*= (h: OutwardNodeHandle[DI, UI, BI])(implicit p: Parameters, sourceInfo: SourceInfo): Option[MonitorBase] = bind(h, BIND_STAR, true)
-  override def :=* (h: OutwardNodeHandle[DI, UI, BI])(implicit p: Parameters, sourceInfo: SourceInfo): Option[MonitorBase] = bind(h, BIND_QUERY)
+  override def :=* (h: OutwardNodeHandle[DI, UI, BI])(implicit p: Parameters, sourceInfo: SourceInfo): Option[MonitorBase] = bind(h, BIND_QUERY, true)
+
+  def connectButDontMonitor(h: OutwardNodeHandle[DI, UI, BI])(implicit p: Parameters, sourceInfo: SourceInfo): Option[MonitorBase] = bind(h, BIND_ONCE, false)
 
   // meta-data for printing the node graph
   protected[diplomacy] def colour  = inner.colour

src/main/scala/rocket/Frontend.scala

@@ -59,8 +59,9 @@ class Frontend(val icacheParams: ICacheParams, hartid: Int, owner: => Option[Dev
   val masterNode = TLOutputNode()
   val slaveNode = TLInputNode()
 
-  icache.slaveNode.map { _ := slaveNode }
   masterNode := icache.masterNode
+  // Avoid breaking tile dedup due to address constants in the monitor
+  icache.slaveNode.map { _ connectButDontMonitor slaveNode }
 }
 
 class FrontendBundle(outer: Frontend) extends CoreBundle()(outer.p) {

src/main/scala/rocketchip/Periphery.scala

@@ -347,10 +347,9 @@ trait HasPeripheryErrorSlave extends HasSystemNetworks {
   private val maxXfer = min(config.address.map(_.alignment).max.toInt, 4096)
   val error = LazyModule(new TLError(config.address, peripheryBusConfig.beatBytes))
 
-  // Override the default Parameters to exclude the TLMonitor between the Fragmenter and error slave.
+  // Most slaves do not support a 4kB burst so this slave ends up with many more source bits than others;
-  // Most slaves do not support a 4kB burst so this slave ends up with many more source bits than others.
+  // we exclude the onerously large TLMonitor that results.
-  private def sourceInfo(implicit x: chisel3.internal.sourceinfo.SourceInfo) = x
+  error.node connectButDontMonitor TLFragmenter(peripheryBusConfig.beatBytes, maxXfer)(peripheryBus.node)
-  error.node.:=(TLFragmenter(peripheryBusConfig.beatBytes, maxXfer)(peripheryBus.node))(new WithoutTLMonitors ++ p, sourceInfo)
 }
 
 

src/main/scala/uncore/tilelink2/Nodes.scala

@@ -24,8 +24,9 @@ object TLImp extends NodeImp[TLClientPortParameters, TLManagerPortParameters, TL
   override def labelI(ei: TLEdgeIn)  = (ei.manager.beatBytes * 8).toString
   override def labelO(eo: TLEdgeOut) = (eo.manager.beatBytes * 8).toString
 
-  override def connect(edges: () => Seq[TLEdgeIn], bundles: () => Seq[(TLBundle, TLBundle)])(implicit p: Parameters, sourceInfo: SourceInfo): (Option[TLMonitorBase], () => Unit) = {
+  override def connect(edges: () => Seq[TLEdgeIn], bundles: () => Seq[(TLBundle, TLBundle)], enableMonitoring: Boolean)
-    val monitor = p(TLMonitorBuilder)(TLMonitorArgs(edges, sourceInfo, p))
+                      (implicit p: Parameters, sourceInfo: SourceInfo): (Option[TLMonitorBase], () => Unit) = {
+    val monitor = if (enableMonitoring) p(TLMonitorBuilder)(TLMonitorArgs(edges, sourceInfo, p)) else None
     (monitor, () => {
       val eval = bundles ()
       monitor.foreach { m => (eval zip m.module.io.in) foreach { case ((i,o), m) => m := TLBundleSnoop(o,i) } }