Make it easier to override the 'placeholder' Real-Time-Clock, to allow more real-world applications

src/main/scala/coreplex/Configs.scala

@@ -128,7 +128,6 @@ class BaseCoreplexConfig extends Config (
       case MtvecInit => BigInt(0x1010)
       case MtvecWritable => true
       //Uncore Paramters
-      case RTCPeriod => 100 // gives 10 MHz RTC assuming 1 GHz uncore clock
       case LNEndpoints => site(TLKey(site(TLId))).nManagers + site(TLKey(site(TLId))).nClients
       case LNHeaderBits => log2Ceil(site(TLKey(site(TLId))).nManagers) +
                              log2Up(site(TLKey(site(TLId))).nClients)

src/main/scala/coreplex/Coreplex.scala

@@ -30,8 +30,6 @@ case object ConfigString extends Field[Array[Byte]]
 case object NExtInterrupts extends Field[Int]
 /** Interrupt controller configuration */
 case object PLICKey extends Field[PLICConfig]
-/** Number of clock cycles per RTC tick */
-case object RTCPeriod extends Field[Int]
 /** The file to read the BootROM contents from */
 case object BootROMFile extends Field[String]
 /** Export an external MMIO slave port */
@@ -73,6 +71,7 @@ class Uncore(implicit val p: Parameters) extends Module
     val mmio = exportMMIO.option(new ClientUncachedTileLinkIO()(outermostMMIOParams))
     val interrupts = Vec(p(NExtInterrupts), Bool()).asInput
     val debug = new DebugBusIO()(p).flip
+    val rtcTick = Bool(INPUT)
   }
 
   val outmemsys = if (nCachedTilePorts + nUncachedTilePorts > 0)
@@ -124,7 +123,7 @@ class Uncore(implicit val p: Parameters) extends Module
     val prci = Module(new PRCI)
     prci.io.tl <> mmioNetwork.port("int:prci")
     io.prci := prci.io.tiles
-    prci.io.rtcTick := Counter(p(RTCPeriod)).inc() // placeholder for real RTC
+    prci.io.rtcTick := io.rtcTick
 
     for (i <- 0 until nTiles) {
       prci.io.interrupts(i).meip := plic.io.harts(plic.cfg.context(i, 'M'))
@@ -237,6 +236,7 @@ abstract class Coreplex(implicit val p: Parameters) extends Module
     val mmio = p(ExportMMIOPort).option(new ClientUncachedTileLinkIO()(outermostMMIOParams))
     val interrupts = Vec(p(NExtInterrupts), Bool()).asInput
     val debug = new DebugBusIO()(p).flip
+    val rtcTick = new Bool(INPUT)
     val extra = p(ExtraCoreplexPorts)(p)
     val success: Option[Bool] = hasSuccessFlag.option(Bool(OUTPUT))
   }
@@ -269,6 +269,8 @@ class DefaultCoreplex(topParams: Parameters) extends Coreplex()(topParams) {
       tile.io.prci <> prci
   }
 
+  uncore.io.rtcTick := io.rtcTick
+
   // Connect the uncore to the tile memory ports, HostIO and MemIO
   uncore.io.tiles_cached <> tileList.map(_.io.cached).flatten
   uncore.io.tiles_uncached <> tileList.map(_.io.uncached).flatten

src/main/scala/rocketchip/Configs.scala

@@ -153,6 +153,8 @@ class BasePlatformConfig extends Config (
       case ExtMemSize => Dump("MEM_SIZE", 0x10000000L)
       case ConfigString => makeConfigString()
       case GlobalAddrMap => globalAddrMap
+      case RTCPeriod => 100 // gives 10 MHz RTC assuming 1 GHz uncore clock
+      case RTC => (p: Parameters, t_io: Bundle, p_io:Bundle) => Counter(p(RTCPeriod)).inc() 
       case _ => throw new CDEMatchError
   }})
 

src/main/scala/rocketchip/RocketChip.scala

@@ -53,6 +53,10 @@ case object ExtMemSize extends Field[Long]
   **/
 case object NExtTopInterrupts extends Field[Int]
 case object NExtPeripheryInterrupts extends Field[Int]
+/** Source of  RTC. First bundle is TopIO.extra, Second bundle is periphery.io.extra  **/
+case object RTC extends Field[(Parameters, Bundle, Bundle) => Bool]
+case object RTCPeriod extends Field[Int]
+
 
 /** Utility trait for quick access to some relevant parameters */
 trait HasTopLevelParameters {
@@ -194,7 +198,11 @@ class Top(topParams: Parameters) extends Module with HasTopLevelParameters {
   coreplex.io.interrupts <> (periphery.io.interrupts ++ io.interrupts)
 
   io.extra <> periphery.io.extra
+
+  coreplex.io.rtcTick := p(RTC)(p, io.extra, periphery.io.extra)
+
   p(ConnectExtraPorts)(io.extra, coreplex.io.extra, p)
+
 }
 
 class Periphery(implicit val p: Parameters) extends Module