Fix issues with request merging in L2 cache and add regression tests

In addition to the fix, there are several additions to the
RegressionTest module. The set of regressions is now parameterized and
split into ones for the cache and ones for the broadcast hub.

groundtest

@@ -1 +1 @@
-Subproject commit 1069aa03c6fcf6234d44599ffca7680c5fcb56af
+Subproject commit f398b3213e3e9411f9014b418a8e7cfa669c5f8b

src/main/scala/TestConfigs.scala

@@ -51,10 +51,20 @@ class WithCacheFillTest extends Config(
     case "L2_CAPACITY_IN_KB" => 4
   })
 
-class WithRegressionTest extends Config(
+class WithBroadcastRegressionTest extends Config(
   (pname, site, here) => pname match {
     case BuildGroundTest =>
       (id: Int, p: Parameters) => Module(new RegressionTest()(p))
+    case GroundTestRegressions =>
+      (p: Parameters) => RegressionTests.broadcastRegressions(p)
+  })
+
+class WithCacheRegressionTest extends Config(
+  (pname, site, here) => pname match {
+    case BuildGroundTest =>
+      (id: Int, p: Parameters) => Module(new RegressionTest()(p))
+    case GroundTestRegressions =>
+      (p: Parameters) => RegressionTests.cacheRegressions(p)
   })
 
 class GroundTestConfig extends Config(new WithGroundTest ++ new DefaultConfig)
@@ -63,8 +73,10 @@ class MemtestL2Config extends Config(
   new WithMemtest ++ new WithL2Cache ++ new GroundTestConfig)
 class CacheFillTestConfig extends Config(
   new WithCacheFillTest ++ new WithL2Cache ++ new GroundTestConfig)
-class RegressionTestConfig extends Config(
-  new WithRegressionTest ++ new GroundTestConfig)
+class BroadcastRegressionTestConfig extends Config(
+  new WithBroadcastRegressionTest ++ new GroundTestConfig)
+class CacheRegressionTestConfig extends Config(
+  new WithCacheRegressionTest ++ new WithL2Cache ++ new GroundTestConfig)
 
 class FancyMemtestConfig extends Config(
   new With2Cores ++ new With2MemoryChannels ++ new With2BanksPerMemChannel ++

uncore

@@ -1 +1 @@
-Subproject commit 9c11a10b2e3b89ca9a14f06a6930eb454bc7f4ec
+Subproject commit ab8a6614f5495ee97c5b8bb82047ebb24cb20d7c