Files
chipyard/generators/firechip/src/main/scala/FireSimMulticlockPOC.scala
2020-06-18 17:25:31 -07:00

108 lines
4.0 KiB
Scala

//See LICENSE for license details.
package firesim.firesim
import chisel3._
import freechips.rocketchip.config.{Field, Config, Parameters}
import freechips.rocketchip.diplomacy.{LazyModule, LazyModuleImp, RationalCrossing}
import freechips.rocketchip.subsystem._
import freechips.rocketchip.util.{ResetCatchAndSync}
import midas.widgets.{Bridge, PeekPokeBridge, RationalClockBridge, RationalClock}
import firesim.configs._
import boom.common.{WithRationalBoomTiles}
import chipyard.{BuildSystem, DigitalTop, DigitalTopModule}
import chipyard.config.ConfigValName._
import chipyard.iobinders.{IOBinders}
// WIP! This file is a sketch of one means of defining a multiclock target-design
// that can be simulated in FireSim, pending a canonicalized form in Chipyard.
//
// Note, the main prerequisite for supporting an additional clock domain in a
// FireSim simulation is to supply an additional clock parameter
// (RationalClock) to the clock bridge (RationalClockBridge). The bridge
// produces a vector of clocks, based on the provided parameter list, which you
// may use freely without further modifications to your target design.
case class FireSimClockParameters(additionalClocks: Seq[RationalClock]) {
def numClocks(): Int = additionalClocks.size + 1
}
case object FireSimClockKey extends Field[FireSimClockParameters](FireSimClockParameters(Seq()))
trait HasAdditionalClocks extends LazyModuleImp {
val clocks = IO(Vec(p(FireSimClockKey).numClocks, Input(Clock())))
}
// Presupposes only 1 or 2 clocks.
trait HasFireSimClockingImp extends HasAdditionalClocks {
val outer: HasTiles
val (tileClock, tileReset) = p(FireSimClockKey).additionalClocks.headOption match {
case Some(RationalClock(_, numer, denom)) if numer != denom => (clocks(1), ResetCatchAndSync(clocks(1), reset.toBool))
case None => (clocks.head, reset)
}
outer.tiles.foreach({ case tile =>
tile.module.clock := tileClock
tile.module.reset := tileReset
})
}
// Config Fragment
class WithSingleRationalTileDomain(multiplier: Int, divisor: Int) extends Config(
new WithRationalRocketTiles ++
new WithRationalBoomTiles ++
new Config((site, here, up) => {
case FireSimClockKey => FireSimClockParameters(Seq(RationalClock("TileDomain", multiplier, divisor)))
})
)
class HalfRateUncore extends WithSingleRationalTileDomain(2,1)
class WithFiresimMulticlockTop extends Config((site, here, up) => {
case BuildSystem => (p: Parameters) => LazyModule(new FiresimMulticlockTop()(p)).suggestName("system")
})
// Complete Config
class FireSimQuadRocketMulticlockConfig extends Config(
new HalfRateUncore ++
new WithFiresimMulticlockTop ++
new FireSimQuadRocketConfig)
// Top Definition
class FiresimMulticlockTop(implicit p: Parameters) extends chipyard.DigitalTop
{
override lazy val module = new FiresimMulticlockTopModule(this)
}
class FiresimMulticlockTopModule[+L <: DigitalTop](l: L) extends chipyard.DigitalTopModule(l) with HasFireSimClockingImp
// Harness Definition
class FireSimMulticlockPOC(implicit val p: Parameters) extends RawModule {
freechips.rocketchip.util.property.cover.setPropLib(new midas.passes.FireSimPropertyLibrary())
val clockBridge = Module(new RationalClockBridge(p(FireSimClockKey).additionalClocks:_*))
val refClock = clockBridge.io.clocks.head
val reset = WireInit(false.B)
withClockAndReset(refClock, reset) {
// Instantiate multiple instances of the DUT to implement supernode
val targets = Seq.fill(p(NumNodes)) {
val lazyModule = p(BuildSystem)(p)
(lazyModule, Module(lazyModule.module))
}
val peekPokeBridge = PeekPokeBridge(refClock, reset)
// A Seq of partial functions that will instantiate the right bridge only
// if that Mixin trait is present in the target's class instance
//
// Apply each partial function to each DUT instance
for ((lazyModule, module) <- targets) {
p(IOBinders).values.foreach(f => f(lazyModule) ++ f(module))
}
targets.collect({ case (_, t: HasAdditionalClocks) => t.clocks := clockBridge.io.clocks })
}
}