From adaec18bec11af88570a18de37467747361bb20c Mon Sep 17 00:00:00 2001
From: Howard Mao <zhehao.mao@gmail.com>
Date: Thu, 14 Jan 2016 22:01:42 -0800
Subject: [PATCH] add TL manager for MMIO requests

---
 uncore/src/main/scala/converters.scala | 68 ++++++++++++++++++++++++++
 uncore/src/main/scala/uncore.scala     |  1 +
 2 files changed, 69 insertions(+)

diff --git a/uncore/src/main/scala/converters.scala b/uncore/src/main/scala/converters.scala
index 22e9532a..509aa2b4 100644
--- a/uncore/src/main/scala/converters.scala
+++ b/uncore/src/main/scala/converters.scala
@@ -729,3 +729,71 @@ class TileLinkIONarrower(innerTLId: String, outerTLId: String)
     }
   } else { io.out <> io.in }
 }
+
+class MMIOTileLinkManagerData(implicit p: Parameters)
+    extends TLBundle()(p)
+    with HasClientId
+    with HasClientTransactionId
+
+class MMIOTileLinkManager(implicit p: Parameters)
+    extends CoherenceAgentModule()(p) {
+  val io = new ManagerTLIO
+
+  // MMIO requests should never need probe or release
+  io.inner.probe.valid := Bool(false)
+  io.inner.release.ready := Bool(false)
+
+  val multibeat_fire = io.outer.acquire.fire() && io.oacq().hasMultibeatData()
+  val multibeat_start = multibeat_fire && io.oacq().addr_beat === UInt(0)
+  val multibeat_end = multibeat_fire && io.oacq().addr_beat === UInt(outerDataBeats - 1)
+
+  // Acquire and Grant are basically passthru,
+  // except client_id and client_xact_id need to be converted.
+  // Associate the inner client_id and client_xact_id
+  // with the outer client_xact_id.
+  val xact_pending = Reg(init = UInt(0, maxManagerXacts))
+  val xact_id_sel = PriorityEncoder(~xact_pending)
+  val xact_id_reg = RegEnable(xact_id_sel, multibeat_start)
+  val xact_multibeat = Reg(init = Bool(false))
+  val outer_xact_id = Mux(xact_multibeat, xact_id_reg, xact_id_sel)
+  val xact_free = !xact_pending.andR
+  val xact_buffer = Reg(Vec(maxManagerXacts, new MMIOTileLinkManagerData))
+
+  io.inner.acquire.ready := io.outer.acquire.ready && xact_free
+  io.outer.acquire.valid := io.inner.acquire.valid && xact_free
+  io.outer.acquire.bits  := io.inner.acquire.bits
+  io.outer.acquire.bits.client_xact_id := outer_xact_id
+
+  def isLastBeat[T <: TileLinkChannel with HasTileLinkBeatId](in: T): Bool =
+    !in.hasMultibeatData() || in.addr_beat === UInt(outerDataBeats - 1)
+
+  def addPendingBitOnAcq[T <: AcquireMetadata](in: DecoupledIO[T]): UInt =
+    Mux(in.fire() && isLastBeat(in.bits), UIntToOH(in.bits.client_xact_id), UInt(0))
+
+  def clearPendingBitOnGnt[T <: GrantMetadata](in: DecoupledIO[T]): UInt =
+    ~Mux(in.fire() && isLastBeat(in.bits) && !in.bits.requiresAck(),
+      UIntToOH(in.bits.manager_xact_id), UInt(0))
+
+  def clearPendingBitOnFin(in: DecoupledIO[Finish]): UInt =
+    ~Mux(in.fire(), UIntToOH(in.bits.manager_xact_id), UInt(0))
+
+  xact_pending := (xact_pending | addPendingBitOnAcq(io.outer.acquire)) &
+                                  clearPendingBitOnFin(io.inner.finish) &
+                                  clearPendingBitOnGnt(io.inner.grant)
+
+  when (io.outer.acquire.fire() && isLastBeat(io.outer.acquire.bits)) {
+    xact_buffer(outer_xact_id) := io.iacq()
+  }
+
+  when (multibeat_start) { xact_multibeat := Bool(true) }
+  when (multibeat_end)   { xact_multibeat := Bool(false) }
+
+  val gnt_xact = xact_buffer(io.ognt().client_xact_id)
+  io.outer.grant.ready := io.inner.grant.ready
+  io.inner.grant.valid := io.outer.grant.valid
+  io.inner.grant.bits  := io.outer.grant.bits
+  io.inner.grant.bits.client_id := gnt_xact.client_id
+  io.inner.grant.bits.client_xact_id := gnt_xact.client_xact_id
+  io.inner.grant.bits.manager_xact_id := io.ognt().client_xact_id
+  io.inner.finish.ready := xact_pending(io.inner.finish.bits.manager_xact_id)
+}
diff --git a/uncore/src/main/scala/uncore.scala b/uncore/src/main/scala/uncore.scala
index 3d38f6b2..34405aae 100644
--- a/uncore/src/main/scala/uncore.scala
+++ b/uncore/src/main/scala/uncore.scala
@@ -32,6 +32,7 @@ trait HasCoherenceAgentParameters {
   val innerWriteMaskBits = innerTLParams.writeMaskBits
   val innerBeatAddrBits = log2Up(innerDataBeats)
   val innerByteAddrBits = log2Up(innerDataBits/8)
+  val maxManagerXacts = innerTLParams.maxManagerXacts
   require(outerDataBeats == innerDataBeats) //TODO: fix all xact_data Vecs to remove this requirement
 }