diff --git a/generators/firechip/src/main/scala/TargetConfigs.scala b/generators/firechip/src/main/scala/TargetConfigs.scala
index 0d8f38dd..ffcb6811 100644
--- a/generators/firechip/src/main/scala/TargetConfigs.scala
+++ b/generators/firechip/src/main/scala/TargetConfigs.scala
@@ -22,6 +22,7 @@ import icenet._
 import firesim.bridges._
 import firesim.util.{WithNumNodes, FireSimClockKey, FireSimClockParameters}
 import firesim.configs._
+import midas.widgets.RationalClock
 
 class WithBootROM extends Config((site, here, up) => {
   case BootROMParams => {
@@ -348,7 +349,7 @@ class FireSimTraceGenL2Config extends Config(
 
 
 class WithRationalTiles(multiplier: Int, divisor: Int) extends Config((site, here, up) => {
-  case FireSimClockKey => FireSimClockParameters(Seq(multiplier -> divisor))
+  case FireSimClockKey => FireSimClockParameters(Seq(RationalClock("TileDomain", multiplier, divisor)))
   case RocketCrossingKey => up(RocketCrossingKey, site) map { r =>
     r.copy(crossingType = RationalCrossing())
   }
diff --git a/generators/firechip/src/main/scala/TargetMixins.scala b/generators/firechip/src/main/scala/TargetMixins.scala
index 55761233..653a450f 100644
--- a/generators/firechip/src/main/scala/TargetMixins.scala
+++ b/generators/firechip/src/main/scala/TargetMixins.scala
@@ -16,6 +16,7 @@ import firesim.bridges.{TracerVBridge}
 import firesim.util.{HasAdditionalClocks, FireSimClockKey}
 
 import midas.targetutils.MemModelAnnotation
+import midas.widgets.RationalClock
 
 import boom.common.BoomTile
 
@@ -80,7 +81,7 @@ trait CanHaveMultiCycleRegfileImp {
 trait HasFireSimClockingImp extends HasAdditionalClocks {
   val outer: HasTiles
   val (tileClock, tileReset) = p(FireSimClockKey).additionalClocks.headOption match {
-    case Some((numer, denom)) if numer != denom => (clocks(1), ResetCatchAndSync(clocks(1), reset.toBool))
+    case Some(RationalClock(_, numer, denom)) if numer != denom => (clocks(1), ResetCatchAndSync(clocks(1), reset.toBool))
     case None => (clocks(0), reset)
   }
 
diff --git a/tools/firrtl b/tools/firrtl
index f738fbe8..7eb1c7c0 160000
--- a/tools/firrtl
+++ b/tools/firrtl
@@ -1 +1 @@
-Subproject commit f738fbe8667ed6b76ec00a15960b9c3a42b8654a
+Subproject commit 7eb1c7c074713335f252bc8e7b48b9f3e057056c