implement mtimer apply

chipsalliance · May 18, 2023 · 8a5c491 · 8a5c491
1 parent 116d696
commit 8a5c491
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Showing 2 changed files with 39 additions and 40 deletions.
diff --git a/src/main/scala/devices/tilelink/MSWI.scala b/src/main/scala/devices/tilelink/MSWI.scala
@@ -87,25 +87,17 @@ class MSWI(mswiParams: MSWIParams, mtimerParams: MTIMERParams, isACLINT: Boolean
     val nTiles  = intnode.out.size
     val ipi     = Seq.fill(nTiles) { RegInit(0.U(1.W)) }
 
-    val io = IO(new Bundle {
-        val rtcTick = (!isACLINT).option(Input(Bool()))
-    })
-
-    val timecmp = (!isACLINT).option(Seq.fill(nTiles) { Reg(UInt(MTIMERConsts.mtimeWidth.W)) })
-    val time    = (!isACLINT).option(RegInit(0.U(MTIMERConsts.mtimeWidth.W)))
-
-    io.rtcTick.map { tick =>
-      when (tick) { time.get := time.get + 1.U }
-    }
-
     val (intnode_out, _) = intnode.out.unzip
     intnode_out.zipWithIndex.foreach { case (int, i) =>
       int(0) := ShiftRegister(ipi(i)(0), mswiParams.intStages)
-      if (!isACLINT) {
-        int(1) := ShiftRegister(time.get.asUInt >= (timecmp.get)(i).asUInt, mtimerParams.intStages)
-      }
     }
 
+    val io = IO(new Bundle {
+        val rtcTick = (!isACLINT).option(Input(Bool()))
+    })
+
+    val mtimerRegGroup: Option[(Seq[RegField], Seq[RegField])] = (!isACLINT).option(MTIMER(io.rtcTick.get, intnode, 1, mtimerParams.intStages))
+
     /* aclint:
      * 0 msip hart 0
      * 4 msip hart 1
@@ -120,19 +112,17 @@ class MSWI(mswiParams: MSWIParams, mtimerParams: MTIMERParams, isACLINT: Boolean
      * bff8 mtime lo
      * bffc mtime hi
      */
-    val mtimerRegGroup = if(!isACLINT) Seq(
-      0x4000 -> timecmp.get.zipWithIndex.flatMap{ case (t, i) => RegFieldGroup(s"mtimecmp_$i", Some(s"MTIMECMP for hart $i"),
-          RegField.bytes(t, Some(RegFieldDesc(s"mtimecmp_$i", "", reset=None))))},
-      0xbff8 -> RegFieldGroup("mtime", Some("Timer Register"),
-          RegField.bytes(time.get, Some(RegFieldDesc("mtime", "", reset=Some(0), volatile=true))))
+    val mtimerRegMapping = if(!isACLINT) Seq(
+      0x4000 -> mtimerRegGroup.get._1,
+      0xbff8 -> mtimerRegGroup.get._2
     ) else Nil
 
-    val mswiRegGroup = Seq(
+    val mswiRegMapping = Seq(
       0 -> RegFieldGroup ("msip", Some("MSIP Bits"), ipi.zipWithIndex.flatMap{ case (r, i) =>
           RegField(1, r, RegFieldDesc(s"msip_$i", s"MSIP bit for Hart $i", reset=Some(0))) :: RegField(MSWIConsts.ipiWidth - 1) :: Nil })
     )
 
-    val mapping = mswiRegGroup ++ mtimerRegGroup
+    val mapping = mswiRegMapping ++ mtimerRegMapping
     node.regmap(mapping:_*)    
   }
 }

diff --git a/src/main/scala/devices/tilelink/Mtimer.scala b/src/main/scala/devices/tilelink/Mtimer.scala
@@ -71,16 +71,7 @@ class MTIMER(params: MTIMERParams, beatBytes: Int)(implicit p: Parameters) exten
       val rtcTick = Input(Bool())
     })
 
-    val time = RegInit(0.U(mtimeWidth.W))
-    when (io.rtcTick) { time := time + 1.U }
-
-    val nTiles = intnode.out.size
-    val timecmp = Seq.fill(nTiles) { Reg(UInt(mtimeWidth.W)) }
-
-    val (intnode_out, _) = intnode.out.unzip
-    intnode_out.zipWithIndex.foreach { case (int, i) =>
-      int(0) := ShiftRegister(time.asUInt >= timecmp(i).asUInt, params.intStages)
-    }
+    val (timecmpRegGroup, timeRegGroup): (Seq[RegField], Seq[RegField]) = MTIMER(io.rtcTick, intnode, 0, params.intStages)
 
     /* 
      * Two base addresses:
@@ -92,14 +83,32 @@ class MTIMER(params: MTIMERParams, beatBytes: Int)(implicit p: Parameters) exten
      * 0 mtime lo
      * 4 mtime hi
      */
-    mtimecmpNode.regmap(
-      0 -> timecmp.zipWithIndex.flatMap{ case (t, i) => RegFieldGroup(s"mtimecmp_$i", Some(s"MTIMECMP for hart $i"),
-            RegField.bytes(t, Some(RegFieldDesc(s"mtimecmp_$i", "", reset=None))))}
-    )
-
-    mtimeNode.regmap(
-      0 -> RegFieldGroup("mtime", Some("Timer Register"),
-            RegField.bytes(time, Some(RegFieldDesc("mtime", "", reset=Some(0), volatile=true))))
-    )
+    mtimecmpNode.regmap(0 -> timecmpRegGroup)
+    mtimeNode.regmap(0 -> timeRegGroup)
+  }
+}
+
+object MTIMER {
+  def apply(rtcTick: Bool, intnode: IntNexusNode, intIndex: Int, intStages: Int) = {
+    import MTIMERConsts._ 
+
+    val time = RegInit(0.U(mtimeWidth.W))
+    when(rtcTick) { time := time + 1.U }
+
+    val nTiles = intnode.out.size
+    val timecmp = Seq.fill(nTiles) { Reg(UInt(mtimeWidth.W)) }
+
+    val (intnode_out, _) = intnode.out.unzip
+    intnode_out.zipWithIndex.foreach { case (int, i) =>
+      int(intIndex) := ShiftRegister(time.asUInt >= timecmp(i).asUInt, intStages)
+    }
+
+    val timecmpRegGroup = timecmp.zipWithIndex.flatMap{ case (t, i) => RegFieldGroup(s"mtimecmp_$i", Some(s"MTIMECMP for hart $i"),
+      RegField.bytes(t, Some(RegFieldDesc(s"mtimecmp_$i", "", reset=None))))}
+
+    val timeRegGroup = RegFieldGroup("mtime", Some("Timer Register"),
+      RegField.bytes(time, Some(RegFieldDesc("mtime", "", reset=Some(0), volatile=true))))
+
+    (timecmpRegGroup, timeRegGroup)
   }
 }