From ba3c83287f9e6e6c4270df892287896ab20276e9 Mon Sep 17 00:00:00 2001
From: "Wesley W. Terpstra" <wesley@sifive.com>
Date: Thu, 3 Nov 2016 19:05:53 -0700
Subject: [PATCH] tilelink2 Xbar: merge the AddressSets of fractured managers

---
 src/main/scala/diplomacy/Parameters.scala     | 21 +++++++++-
 .../scala/uncore/tilelink2/Parameters.scala   | 42 +++++++++++++++++++
 src/main/scala/uncore/tilelink2/Xbar.scala    |  4 +-
 3 files changed, 64 insertions(+), 3 deletions(-)

diff --git a/src/main/scala/diplomacy/Parameters.scala b/src/main/scala/diplomacy/Parameters.scala
index e494f6e7..a262966a 100644
--- a/src/main/scala/diplomacy/Parameters.scala
+++ b/src/main/scala/diplomacy/Parameters.scala
@@ -144,5 +144,24 @@ object AddressSet
       misaligned(base+step, size-step, AddressSet(base, step-1) +: tail)
     }
   }
-}
 
+  def unify(seq: Seq[AddressSet]): Seq[AddressSet] = {
+    val n = seq.size
+    val array = Array(seq:_*)
+    var filter = Array.fill(n) { false }
+    for (i <- 0 until n-1) { if (!filter(i)) {
+      for (j <- i+1 until n) { if (!filter(j)) {
+        val a = array(i)
+        val b = array(j)
+        if (a.mask == b.mask && isPow2(a.base ^ b.base)) {
+          val c_base = a.base & ~(a.base ^ b.base)
+          val c_mask = a.mask | (a.base ^ b.base)
+          filter.update(j, true)
+          array.update(i, AddressSet(c_base, c_mask))
+        }
+      }}
+    }}
+    val out = (array zip filter) flatMap { case (a, f) => if (f) None else Some(a) }
+    if (out.size != n) unify(out) else out.toList
+  }
+}
diff --git a/src/main/scala/uncore/tilelink2/Parameters.scala b/src/main/scala/uncore/tilelink2/Parameters.scala
index 0a0da860..f732efd9 100644
--- a/src/main/scala/uncore/tilelink2/Parameters.scala
+++ b/src/main/scala/uncore/tilelink2/Parameters.scala
@@ -287,3 +287,45 @@ case class TLAsyncEdgeParameters(client: TLAsyncClientPortParameters, manager: T
 {
   val bundle = TLAsyncBundleParameters(manager.depth, TLBundleParameters(client.base, manager.base))
 }
+
+object ManagerUnification
+{
+  def apply(managers: Seq[TLManagerParameters]) = {
+    // To be unified, devices must agree on all of these terms
+    case class TLManagerKey(
+      regionType:         RegionType.T,
+      executable:         Boolean,
+      lastNode:           BaseNode,
+      supportsAcquire:    TransferSizes,
+      supportsArithmetic: TransferSizes,
+      supportsLogical:    TransferSizes,
+      supportsGet:        TransferSizes,
+      supportsPutFull:    TransferSizes,
+      supportsPutPartial: TransferSizes,
+      supportsHint:       TransferSizes)
+    def key(x: TLManagerParameters) = TLManagerKey(
+      regionType         = x.regionType,
+      executable         = x.executable,
+      lastNode           = x.nodePath.last,
+      supportsAcquire    = x.supportsAcquire,
+      supportsArithmetic = x.supportsArithmetic,
+      supportsLogical    = x.supportsLogical,
+      supportsGet        = x.supportsGet,
+      supportsPutFull    = x.supportsPutFull,
+      supportsPutPartial = x.supportsPutPartial,
+      supportsHint       = x.supportsHint)
+    val map = scala.collection.mutable.HashMap[TLManagerKey, TLManagerParameters]()
+    managers.foreach { m =>
+      val k = key(m)
+      map.get(k) match {
+        case None => map.update(k, m)
+        case Some(n) => {
+          map.update(k, m.copy(
+            address = m.address ++ n.address,
+            fifoId  = None)) // Merging means it's not FIFO anymore!
+        }
+      }
+    }
+    map.values.map(m => m.copy(address = AddressSet.unify(m.address))).toList
+  }
+}
diff --git a/src/main/scala/uncore/tilelink2/Xbar.scala b/src/main/scala/uncore/tilelink2/Xbar.scala
index f4c6a82b..6e2b64a0 100644
--- a/src/main/scala/uncore/tilelink2/Xbar.scala
+++ b/src/main/scala/uncore/tilelink2/Xbar.scala
@@ -54,13 +54,13 @@ class TLXbar(policy: TLArbiter.Policy = TLArbiter.lowestIndexFirst) extends Lazy
       seq(0).copy(
         minLatency = seq.map(_.minLatency).min,
         endSinkId = outputIdRanges.map(_.end).max,
-        managers = (outputIdRanges zip seq) flatMap { case (range, port) =>
+        managers = ManagerUnification(seq.flatMap { port =>
           require (port.beatBytes == seq(0).beatBytes)
           val fifoIdMapper = fifoIdFactory()
           port.managers map { manager => manager.copy(
             fifoId = manager.fifoId.map(fifoIdMapper(_))
           )}
-        }
+        })
       )
     })