rocket: only cache when AcquireT is possible

chipsalliance · Oct 11, 2017 · 1867a5b · 1867a5b
1 parent 3740670
commit 1867a5b
Show file tree

Hide file tree

Showing 4 changed files with 7 additions and 8 deletions.
diff --git a/src/main/scala/rocket/DCache.scala b/src/main/scala/rocket/DCache.scala
@@ -381,7 +381,7 @@ class DCacheModule(outer: DCache) extends HellaCacheModule(outer) {
   val access_address = s2_req.addr
   val a_size = mtSize(s2_req.typ)
   val a_data = Fill(beatWords, pstore1_data)
-  val acquire = if (edge.manager.anySupportAcquireB) {
+  val acquire = if (edge.manager.anySupportAcquireT) {
     edge.AcquireBlock(UInt(0), acquire_address, lgCacheBlockBytes, s2_grow_param)._2 // Cacheability checked by tlb
   } else {
     Wire(new TLBundleA(edge.bundle))
@@ -583,7 +583,7 @@ class DCacheModule(outer: DCache) extends HellaCacheModule(outer) {
     when (releaseDone) { release_state := s_probe_write_meta }
   }
   when (release_state.isOneOf(s_voluntary_writeback, s_voluntary_write_meta)) {
-    if (edge.manager.anySupportAcquireB)
+    if (edge.manager.anySupportAcquireT)
       tl_out_c.bits := edge.Release(fromSource = 0.U,
                                     toAddress = 0.U,
                                     lgSize = lgCacheBlockBytes,
@@ -696,7 +696,7 @@ class DCacheModule(outer: DCache) extends HellaCacheModule(outer) {
   metaArb.io.in(5).bits.way_en := ~UInt(0, nWays)
   metaArb.io.in(5).bits.data := metaArb.io.in(4).bits.data
   // Only flush D$ on FENCE.I if some cached executable regions are untracked.
-  if (!edge.manager.managers.forall(m => !m.supportsAcquireB || !m.executable || m.regionType >= RegionType.TRACKED)) {
+  if (!edge.manager.managers.forall(m => !m.supportsAcquireT || !m.executable || m.regionType >= RegionType.TRACKED)) {
     when (tl_out_a.fire() && !s2_uncached) { flushed := false }
     when (flushing) {
       s1_victim_way := flushCounter >> log2Up(nSets)

diff --git a/src/main/scala/rocket/TLB.scala b/src/main/scala/rocket/TLB.scala
@@ -112,7 +112,7 @@ class TLB(instruction: Boolean, lgMaxSize: Int, nEntries: Int)(implicit edge: TL
   val legal_address = edge.manager.findSafe(mpu_physaddr).reduce(_||_)
   def fastCheck(member: TLManagerParameters => Boolean) =
     legal_address && edge.manager.fastProperty(mpu_physaddr, member, (b:Boolean) => Bool(b))
-  val cacheable = fastCheck(_.supportsAcquireB) && (instruction || !usingDataScratchpad)
+  val cacheable = fastCheck(_.supportsAcquireT) && (instruction || !usingDataScratchpad)
   val homogeneous = TLBPageLookup(edge.manager.managers, xLen, p(CacheBlockBytes), BigInt(1) << pgIdxBits)(mpu_physaddr).homogeneous
   val prot_r = fastCheck(_.supportsGet) && pmp.io.r
   val prot_w = fastCheck(_.supportsPutFull) && pmp.io.w

diff --git a/src/main/scala/rocket/TLBPermissions.scala b/src/main/scala/rocket/TLBPermissions.scala
@@ -46,7 +46,6 @@ object TLBPageLookup
       require (!m.supportsAcquireT   || m.supportsAcquireT  .contains(xferSizes), s"MemoryMap region ${m.name} only supports ${m.supportsAcquireT} AcquireT, but must support ${xferSizes}")
       require (!m.supportsLogical    || m.supportsLogical   .contains(amoSizes),  s"MemoryMap region ${m.name} only supports ${m.supportsLogical} Logical, but must support ${amoSizes}")
       require (!m.supportsArithmetic || m.supportsArithmetic.contains(amoSizes),  s"MemoryMap region ${m.name} only supports ${m.supportsArithmetic} Arithmetic, but must support ${amoSizes}")
-      require (m.supportsAcquireT || !m.supportsAcquireB, s"MemoryMap region ${m.name} supports AcquireB (cached read) but not AcquireT (cached write)... and rocket assumes this")
 
       (m.address, TLBFixedPermissions(
         e = Seq(RegionType.PUT_EFFECTS, RegionType.GET_EFFECTS) contains m.regionType,

diff --git a/src/main/scala/tilelink/CacheCork.scala b/src/main/scala/tilelink/CacheCork.scala
@@ -19,9 +19,9 @@ class TLCacheCork(unsafe: Boolean = false)(implicit p: Parameters) extends LazyM
     managerFn = { case mp =>
       mp.copy(
         endSinkId = 1,
-        managers = mp.managers.map { m => m.copy( // Rocket requires m.supportsAcquireT || !m.supportsAcquireB, so, don't cache ROMs
-          supportsAcquireB = if (m.regionType == RegionType.UNCACHED && m.supportsPutFull) m.supportsGet     else m.supportsAcquireB,
-          supportsAcquireT = if (m.regionType == RegionType.UNCACHED)                      m.supportsPutFull else m.supportsAcquireT)})})
+        managers = mp.managers.map { m => m.copy(
+          supportsAcquireB = if (m.regionType == RegionType.UNCACHED) m.supportsGet     else m.supportsAcquireB,
+          supportsAcquireT = if (m.regionType == RegionType.UNCACHED) m.supportsPutFull else m.supportsAcquireT)})})
 
   lazy val module = new LazyModuleImp(this) {
     (node.in zip node.out) foreach { case ((in, edgeIn), (out, edgeOut)) =>