1
0
rocket-chip/src/main/scala/util/Broadcaster.scala

49 lines
1.2 KiB
Scala
Raw Normal View History

// See LICENSE.SiFive for license details.
// See LICENSE.Berkeley for license details.
package freechips.rocketchip.util
import Chisel._
/** Takes in data on one decoupled interface and broadcasts it
* to N decoupled output interfaces.
*/
class Broadcaster[T <: Data](typ: T, n: Int) extends Module {
val io = new Bundle {
val in = Decoupled(typ).flip
val out = Vec(n, Decoupled(typ))
}
require (n > 0)
if (n == 1) {
io.out.head <> io.in
} else {
val idx = Reg(init = UInt(0, log2Up(n)))
val save = Reg(typ)
io.out.head.valid := idx === UInt(0) && io.in.valid
io.out.head.bits := io.in.bits
for (i <- 1 until n) {
io.out(i).valid := idx === UInt(i)
io.out(i).bits := save
}
io.in.ready := io.out.head.ready && idx === UInt(0)
when (io.in.fire()) { save := io.in.bits }
when (io.out(idx).fire()) {
when (idx === UInt(n - 1)) { idx := UInt(0) }
.otherwise { idx := idx + UInt(1) }
}
}
}
object Broadcaster {
def apply[T <: Data](in: DecoupledIO[T], n: Int): Vec[DecoupledIO[T]] = {
val split = Module(new Broadcaster(in.bits, n))
split.io.in <> in
split.io.out
}
}