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rocket-chip/src/main/scala/coreplex/PeripheryBus.scala
2017-10-26 13:04:32 -07:00

65 lines
1.9 KiB
Scala

// See LICENSE.SiFive for license details.
package freechips.rocketchip.coreplex
import Chisel._
import freechips.rocketchip.config.{Field, Parameters}
import freechips.rocketchip.diplomacy._
import freechips.rocketchip.tilelink._
import freechips.rocketchip.config.Field
case class PeripheryBusParams(
beatBytes: Int,
blockBytes: Int,
masterBuffering: BufferParams = BufferParams.default,
slaveBuffering: BufferParams = BufferParams.none,
arithmetic: Boolean = true,
frequency: BigInt = BigInt(100000000) // 100 MHz as default bus frequency
) extends TLBusParams {
}
case object PeripheryBusKey extends Field[PeripheryBusParams]
class PeripheryBus(params: PeripheryBusParams)(implicit p: Parameters) extends TLBusWrapper(params, "PeripheryBus") {
def toFixedWidthSingleBeatSlave(widthBytes: Int) = {
TLFragmenter(widthBytes, params.blockBytes)(outwardWWNode)
}
def toLargeBurstSlave(maxXferBytes: Int) = {
TLFragmenter(params.beatBytes, maxXferBytes)(outwardBufNode)
}
val fromSystemBus: TLInwardNode = {
val atomics = LazyModule(new TLAtomicAutomata(arithmetic = params.arithmetic))
inwardBufNode := atomics.node
atomics.node
}
def toTile(name: Option[String] = None)(gen: Parameters => TLInwardNode) {
this {
LazyScope(s"${busName}ToTile${name.getOrElse("")}") {
SinkCardinality { implicit p =>
FlipRendering { implicit p =>
gen(p) :*= outwardNode
}
}
}
}
}
}
/** Provides buses that serve as attachment points,
* for use in traits that connect individual devices or external ports.
*/
trait HasPeripheryBus extends HasSystemBus {
private val pbusParams = p(PeripheryBusKey)
val pbusBeatBytes = pbusParams.beatBytes
val pbus = LazyModule(new PeripheryBus(pbusParams))
// The peripheryBus hangs off of systemBus; here we convert TL-UH -> TL-UL
pbus.fromSystemBus := sbus.toPeripheryBus()
}