TraceDoctor

src/main/scala/rocket/CSR.scala

@@ -205,6 +205,11 @@ class PerfCounterIO(implicit p: Parameters) extends CoreBundle
   val inc = UInt(INPUT, log2Ceil(1+retireWidth))
 }
 
+class TraceDoctor(val traceWidth: Int) extends Bundle {
+  val valid = Bool()
+  val bits = Vec(traceWidth, Bool())
+}
+
 class TracedInstruction(implicit p: Parameters) extends CoreBundle {
   val valid = Bool()
   val iaddr = UInt(width = coreMaxAddrBits)

src/main/scala/rocket/RocketCore.scala

@@ -49,7 +49,8 @@ case class RocketCoreParams(
   mvendorid: Int = 0, // 0 means non-commercial implementation
   mimpid: Int = 0x20181004, // release date in BCD
   mulDiv: Option[MulDivParams] = Some(MulDivParams()),
-  fpu: Option[FPUParams] = Some(FPUParams())
+  fpu: Option[FPUParams] = Some(FPUParams()),
+  setTraceDoctorWidth: Int = 0
 ) extends CoreParams {
   val lgPauseCycles = 5
   val haveFSDirty = false
@@ -62,6 +63,8 @@ case class RocketCoreParams(
   val lrscCycles: Int = 80 // worst case is 14 mispredicted branches + slop
   override def minFLen: Int = fpu.map(_.minFLen).getOrElse(32)
   override def customCSRs(implicit p: Parameters) = new RocketCustomCSRs
+
+  override def traceDoctorWidth: Int = setTraceDoctorWidth
 }
 
 trait HasRocketCoreParameters extends HasCoreParameters {
@@ -949,6 +952,24 @@ class Rocket(tile: RocketTile)(implicit p: Parameters) extends CoreModule()(p)
   coreMonitorBundle.excpt := csr.io.trace(0).exception
   coreMonitorBundle.priv_mode := csr.io.trace(0).priv
 
+  if (io.traceDoctor.traceWidth >= (64 + 64 + (retireWidth * 64))) {
+    val traceValids = for (i <- 0 until retireWidth) yield {
+      csr.io.trace(i).valid
+    }
+    val traceTimestamp = csr.io.time
+    val traceAddresses = for (i <- 0 until retireWidth) yield {
+      csr.io.trace(0).iaddr(vaddrBitsExtended-1, 0).sextTo(xLen)
+    }
+    val coreStalled = csr.io.csr_stall
+
+    io.traceDoctor.valid := traceValids.reduce(_||_) && !coreStalled
+    io.traceDoctor.bits := Cat(Seq(
+      traceTimestamp(63, 0).pad(64),
+      traceValids.reverse.asUInt()(retireWidth - 1, 0).pad(64),
+      traceAddresses.map(a => a(63, 0).pad(64)).reverse.asUInt()
+    ).reverse).pad(io.traceDoctor.traceWidth).asBools
+  }
+
   if (enableCommitLog) {
     val t = csr.io.trace(0)
     val rd = wb_waddr

src/main/scala/tile/BaseTile.scala

@@ -92,7 +92,7 @@ trait HasNonDiplomaticTileParameters {
   def masterPortBeatBytes = p(SystemBusKey).beatBytes
 
   // TODO make HellaCacheIO diplomatic and remove this brittle collection of hacks
-  //                  Core   PTW                DTIM                    coprocessors           
+  //                  Core   PTW                DTIM                    coprocessors
   def dcacheArbPorts = 1 + usingVM.toInt + usingDataScratchpad.toInt + p(BuildRoCC).size + tileParams.core.useVector.toInt
 
   // TODO merge with isaString in CSR.scala
@@ -265,6 +265,10 @@ abstract class BaseTile private (val crossing: ClockCrossingType, q: Parameters)
   //       assuming the core itself is diplomatic.
   //       Then these nodes should just become IdentityNodes of their respective type
 
+  val traceDoctorSourceNode = BundleBridgeSource(() => new TraceDoctor(tileParams.core.traceDoctorWidth))
+  private val traceDoctorNexus = BundleBroadcast[TraceDoctor]() // backwards compatiblity; not blocked during stretched reset
+  val traceDoctorNode: BundleBridgeOutwardNode[TraceDoctor] = traceDoctorNexus := traceDoctorSourceNode
+
   protected def traceRetireWidth = tileParams.core.retireWidth
   /** Node for the core to drive legacy "raw" instruction trace. */
   val traceSourceNode = BundleBridgeSource(() => Vec(traceRetireWidth, new TracedInstruction()))

src/main/scala/tile/Core.scala

@@ -50,6 +50,9 @@ trait CoreParams {
   val nPTECacheEntries: Int
   val mtvecInit: Option[BigInt]
   val mtvecWritable: Boolean
+
+  def traceDoctorWidth: Int = 0
+
   def customCSRs(implicit p: Parameters): CustomCSRs = new CustomCSRs
 
   def hasSupervisorMode: Boolean = useSupervisor || useVM
@@ -149,6 +152,7 @@ trait HasCoreIO extends HasTileParameters {
     val fpu = new FPUCoreIO().flip
     val rocc = new RoCCCoreIO().flip
     val trace = Vec(coreParams.retireWidth, new TracedInstruction).asOutput
+    val traceDoctor = new TraceDoctor(coreParams.traceDoctorWidth).asOutput
     val bpwatch = Vec(coreParams.nBreakpoints, new BPWatch(coreParams.retireWidth)).asOutput
     val cease = Bool().asOutput
     val wfi = Bool().asOutput

src/main/scala/tile/RocketTile.scala

@@ -151,6 +151,8 @@ class RocketTileModuleImp(outer: RocketTile) extends BaseTileModuleImp(outer)
 
   // Pass through various external constants and reports that were bundle-bridged into the tile
   outer.traceSourceNode.bundle <> core.io.trace
+  outer.traceDoctorSourceNode.bundle <> core.io.traceDoctor
+
   core.io.traceStall := outer.traceAuxSinkNode.bundle.stall
   outer.bpwatchSourceNode.bundle <> core.io.bpwatch
   core.io.hartid := outer.hartIdSinkNode.bundle