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rocket-chip/src/main/scala/rocket/tile.scala
Andrew Waterman 63679bb019 Add support for L1 data scratchpads instead of caches
They fit in the same part of the address space as DRAM would be, and
are coherent (because they are not cacheable).

They are currently limited to single cores without DRAM.  We intend
to lift both restrictions, probably when we add support for
heterogeneous tiles.
2016-09-02 16:22:07 -07:00

144 lines
4.9 KiB
Scala

// See LICENSE for license details.
package rocket
import Chisel._
import uncore.tilelink._
import uncore.agents._
import uncore.converters._
import uncore.devices._
import Util._
import cde.{Parameters, Field}
case object BuildRoCC extends Field[Seq[RoccParameters]]
case object NCachedTileLinkPorts extends Field[Int]
case object NUncachedTileLinkPorts extends Field[Int]
case object TileId extends Field[Int]
case class RoccParameters(
opcodes: OpcodeSet,
generator: Parameters => RoCC,
nMemChannels: Int = 0,
nPTWPorts : Int = 0,
useFPU: Boolean = false)
abstract class Tile(clockSignal: Clock = null, resetSignal: Bool = null)
(implicit p: Parameters) extends Module(Option(clockSignal), Option(resetSignal)) {
val nCachedTileLinkPorts = p(NCachedTileLinkPorts)
val nUncachedTileLinkPorts = p(NUncachedTileLinkPorts)
val dcacheParams = p.alterPartial({ case CacheName => "L1D" })
class TileIO extends Bundle {
val cached = Vec(nCachedTileLinkPorts, new ClientTileLinkIO)
val uncached = Vec(nUncachedTileLinkPorts, new ClientUncachedTileLinkIO)
val prci = new PRCITileIO().flip
val slave = (p(DataScratchpadSize) > 0).option(new ClientUncachedTileLinkIO().flip)
}
val io = new TileIO
}
class RocketTile(clockSignal: Clock = null, resetSignal: Bool = null)
(implicit p: Parameters) extends Tile(clockSignal, resetSignal)(p) {
val buildRocc = p(BuildRoCC)
val usingRocc = !buildRocc.isEmpty
val nRocc = buildRocc.size
val nFPUPorts = buildRocc.filter(_.useFPU).size
val core = Module(new Rocket)
val icache = Module(new Frontend()(p.alterPartial({ case CacheName => "L1I" })))
val dcache = HellaCache(p(DCacheKey))(dcacheParams)
val ptwPorts = collection.mutable.ArrayBuffer(icache.io.ptw, dcache.ptw)
val dcPorts = collection.mutable.ArrayBuffer(core.io.dmem)
val uncachedArbPorts = collection.mutable.ArrayBuffer(icache.io.mem)
val uncachedPorts = collection.mutable.ArrayBuffer[ClientUncachedTileLinkIO]()
val cachedPorts = collection.mutable.ArrayBuffer(dcache.mem)
core.io.prci <> io.prci
icache.io.cpu <> core.io.imem
val fpuOpt = p(FPUKey).map(cfg => Module(new FPU(cfg)))
fpuOpt.foreach(fpu => core.io.fpu <> fpu.io)
if (usingRocc) {
val respArb = Module(new RRArbiter(new RoCCResponse, nRocc))
core.io.rocc.resp <> respArb.io.out
val roccOpcodes = buildRocc.map(_.opcodes)
val cmdRouter = Module(new RoccCommandRouter(roccOpcodes))
cmdRouter.io.in <> core.io.rocc.cmd
val roccs = buildRocc.zipWithIndex.map { case (accelParams, i) =>
val rocc = accelParams.generator(p.alterPartial({
case RoccNMemChannels => accelParams.nMemChannels
case RoccNPTWPorts => accelParams.nPTWPorts
}))
val dcIF = Module(new SimpleHellaCacheIF()(dcacheParams))
rocc.io.cmd <> cmdRouter.io.out(i)
rocc.io.exception := core.io.rocc.exception
dcIF.io.requestor <> rocc.io.mem
dcPorts += dcIF.io.cache
uncachedArbPorts += rocc.io.autl
rocc
}
if (nFPUPorts > 0) {
fpuOpt.foreach { fpu =>
val fpArb = Module(new InOrderArbiter(new FPInput, new FPResult, nFPUPorts))
val fp_roccs = roccs.zip(buildRocc)
.filter { case (_, params) => params.useFPU }
.map { case (rocc, _) => rocc.io }
fpArb.io.in_req <> fp_roccs.map(_.fpu_req)
fp_roccs.zip(fpArb.io.in_resp).foreach {
case (rocc, fpu_resp) => rocc.fpu_resp <> fpu_resp
}
fpu.io.cp_req <> fpArb.io.out_req
fpArb.io.out_resp <> fpu.io.cp_resp
}
}
core.io.rocc.busy := cmdRouter.io.busy || roccs.map(_.io.busy).reduce(_ || _)
core.io.rocc.interrupt := roccs.map(_.io.interrupt).reduce(_ || _)
respArb.io.in <> roccs.map(rocc => Queue(rocc.io.resp))
ptwPorts ++= roccs.flatMap(_.io.ptw)
uncachedPorts ++= roccs.flatMap(_.io.utl)
}
val uncachedArb = Module(new ClientUncachedTileLinkIOArbiter(uncachedArbPorts.size))
uncachedArb.io.in <> uncachedArbPorts
uncachedArb.io.out +=: uncachedPorts
// Connect the caches and RoCC to the outer memory system
io.uncached <> uncachedPorts
io.cached <> cachedPorts
// TODO remove nCached/nUncachedTileLinkPorts parameters and these assertions
require(uncachedPorts.size == nUncachedTileLinkPorts)
require(cachedPorts.size == nCachedTileLinkPorts)
if (p(UseVM)) {
val ptw = Module(new PTW(ptwPorts.size)(dcacheParams))
ptw.io.requestor <> ptwPorts
ptw.io.mem +=: dcPorts
core.io.ptw <> ptw.io.dpath
}
io.slave foreach { case slavePort =>
val adapter = Module(new ScratchpadSlavePort()(dcacheParams))
adapter.io.tl <> TileLinkFragmenter(slavePort)
adapter.io.dmem +=: dcPorts
}
require(dcPorts.size == core.dcacheArbPorts)
val dcArb = Module(new HellaCacheArbiter(dcPorts.size)(dcacheParams))
dcArb.io.requestor <> dcPorts
dcache.cpu <> dcArb.io.mem
if (nFPUPorts == 0) {
fpuOpt.foreach { fpu =>
fpu.io.cp_req.valid := Bool(false)
fpu.io.cp_resp.ready := Bool(false)
}
}
}