tilelink2 Nodes: include some options to test for conformance

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

@@ -21,6 +21,9 @@ object TLImp extends NodeImp[TLClientPortParameters, TLManagerPortParameters, TL
   }
 
   var emitMonitors = true
+  var stressTestDecoupled = false
+  var combinationalCheck = false
+
   def colour = "#000000" // black
   def connect(bo: => TLBundle, bi: => TLBundle, ei: => TLEdgeIn)(implicit sourceInfo: SourceInfo): (Option[LazyModule], () => Unit) = {
     val monitor = if (emitMonitors) {
@@ -31,6 +34,40 @@ object TLImp extends NodeImp[TLClientPortParameters, TLManagerPortParameters, TL
     (monitor, () => {
       bi <> bo
       monitor.foreach { _.module.io.in := TLBundleSnoop(bo) }
+      if (combinationalCheck) {
+        // It is forbidden for valid to depend on ready in TL2
+        // If someone did that, then this will create a detectable combinational loop
+        bo.a.ready := bi.a.ready && bo.a.valid
+        bi.b.ready := bo.b.ready && bi.b.valid
+        bo.c.ready := bi.c.ready && bo.c.valid
+        bi.d.ready := bo.d.ready && bi.d.valid
+        bo.e.ready := bi.e.ready && bo.e.valid
+      }
+      if (stressTestDecoupled) {
+        // Randomly stall the transfers
+        val allow = LFSRNoiseMaker(5)
+        bi.a.valid := bo.a.valid && allow(0)
+        bo.a.ready := bi.a.ready && allow(0)
+        bo.b.valid := bi.b.valid && allow(1)
+        bi.b.ready := bo.b.ready && allow(1)
+        bi.c.valid := bo.c.valid && allow(2)
+        bo.c.ready := bi.c.ready && allow(2)
+        bo.d.valid := bi.d.valid && allow(3)
+        bi.d.ready := bo.d.ready && allow(3)
+        bi.e.valid := bo.e.valid && allow(4)
+        bo.e.ready := bi.e.ready && allow(4)
+        // Inject garbage whenever not valid
+        val bits_a = bo.a.bits.fromBits(LFSRNoiseMaker(bo.a.bits.asUInt.getWidth))
+        val bits_b = bi.b.bits.fromBits(LFSRNoiseMaker(bi.b.bits.asUInt.getWidth))
+        val bits_c = bo.c.bits.fromBits(LFSRNoiseMaker(bo.c.bits.asUInt.getWidth))
+        val bits_d = bi.d.bits.fromBits(LFSRNoiseMaker(bi.d.bits.asUInt.getWidth))
+        val bits_e = bo.e.bits.fromBits(LFSRNoiseMaker(bo.e.bits.asUInt.getWidth))
+        when (!bi.a.valid) { bi.a.bits := bits_a }
+        when (!bo.b.valid) { bo.b.bits := bits_b }
+        when (!bi.c.valid) { bi.c.bits := bits_c }
+        when (!bo.d.valid) { bo.d.bits := bits_d }
+        when (!bi.e.valid) { bi.e.bits := bits_e }
+      }
     })
   }