From c8e6d478840909915ac69aa38820b132d9dd50c7 Mon Sep 17 00:00:00 2001
From: "Wesley W. Terpstra" <wesley@sifive.com>
Date: Tue, 13 Sep 2016 16:04:46 -0700
Subject: [PATCH] tilelink2: add a clock crossing adapter

---
 src/main/scala/uncore/tilelink2/Buffer.scala  |  2 +-
 .../scala/uncore/tilelink2/Crossing.scala     | 42 +++++++++++++++++++
 2 files changed, 43 insertions(+), 1 deletion(-)
 create mode 100644 src/main/scala/uncore/tilelink2/Crossing.scala

diff --git a/src/main/scala/uncore/tilelink2/Buffer.scala b/src/main/scala/uncore/tilelink2/Buffer.scala
index adfe4c4b..558a524a 100644
--- a/src/main/scala/uncore/tilelink2/Buffer.scala
+++ b/src/main/scala/uncore/tilelink2/Buffer.scala
@@ -22,7 +22,7 @@ class TLBuffer(entries: Int = 2, pipe: Boolean = false) extends LazyModule
       if (edgeOut.manager.anySupportAcquire && edgeOut.client.anySupportProbe) {
         in .b <> Queue(out.b, entries, pipe)
         out.c <> Queue(in .c, entries, pipe)
-        out.e <> Queue(out.e, entries, pipe)
+        out.e <> Queue(in .e, entries, pipe)
       } else {
         in.b.valid := Bool(false)
         in.c.ready := Bool(true)
diff --git a/src/main/scala/uncore/tilelink2/Crossing.scala b/src/main/scala/uncore/tilelink2/Crossing.scala
new file mode 100644
index 00000000..1f903c9a
--- /dev/null
+++ b/src/main/scala/uncore/tilelink2/Crossing.scala
@@ -0,0 +1,42 @@
+// See LICENSE for license details.
+
+package uncore.tilelink2
+
+import Chisel._
+import chisel3.internal.sourceinfo.SourceInfo
+import junctions._
+
+class TLAsyncCrossing(depth: Int = 8, sync: Int = 3) extends LazyModule
+{
+  val node = TLIdentityNode()
+
+  lazy val module = new LazyModuleImp(this) {
+    val io = new Bundle {
+      val in        = node.bundleIn
+      val in_clock  = Clock(INPUT)
+      val in_reset  = Bool(INPUT)
+      val out       = node.bundleOut
+      val out_clock = Clock(INPUT)
+      val out_reset = Bool(INPUT)
+    }
+
+    // Transfer all TL2 bundles from/to the same domains
+    ((io.in zip io.out) zip (node.edgesIn zip node.edgesOut)) foreach { case ((in, out), (edgeIn, edgeOut)) =>
+      out.a <> AsyncDecoupledCrossing(io.in_clock, io.in_reset, in.a, io.out_clock, io.out_reset, depth, sync)
+      in.d <> AsyncDecoupledCrossing(io.out_clock, io.out_reset, out.d, io.in_clock, io.in_reset, depth, sync)
+
+      if (edgeOut.manager.anySupportAcquire && edgeOut.client.anySupportProbe) {
+        in.b <> AsyncDecoupledCrossing(io.out_clock, io.out_reset, out.b, io.in_clock, io.in_reset, depth, sync)
+        out.c <> AsyncDecoupledCrossing(io.in_clock, io.in_reset, in.c, io.out_clock, io.out_reset, depth, sync)
+        out.e <> AsyncDecoupledCrossing(io.in_clock, io.in_reset, in.e, io.out_clock, io.out_reset, depth, sync)
+      } else {
+        in.b.valid := Bool(false)
+        in.c.ready := Bool(true)
+        in.e.ready := Bool(true)
+        out.b.ready := Bool(true)
+        out.c.valid := Bool(false)
+        out.e.valid := Bool(false)
+      }
+    }
+  }
+}