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rocket-chip/src/main/scala/RocketChip.scala
Palmer Dabbelt 926efd0cab Allow the number of memory channels to be picked at runtime
We're building a chip with 8 memory channels.  Since this will require a
complicated test setup we want to also be able to bring up the chip with fewer
memory channels.  This commit adds a SCR that controls the number of active
memory channels on a chip.  Toggling this SCR will scramble memory and drop
Nasti messages, so it's only possible to change while the chip is booting.

By default this just adds a 1-bit SCR, which essentially no extra logic.

When multiple memory channel configurations are enabled at elaboration time, a
NastiMemoryInterconnect is generated for each channel configuration.  The
number of outstanding misses is increased to coorespond to the maximum number
of banks per memory channel (added as a parameter), which I believe is
necessary to avoid deadlock in the memory system.

A configuration is added that supports 8 memory channels but has only 1 enabled
by default.
2016-02-17 15:23:30 -08:00

339 lines
13 KiB
Scala

// See LICENSE for license details.
package rocketchip
import Chisel._
import cde.{Parameters, Field}
import junctions._
import uncore._
import rocket._
import rocket.Util._
/** Top-level parameters of RocketChip, values set in e.g. PublicConfigs.scala */
/** Number of tiles */
case object NTiles extends Field[Int]
/** Number of memory channels */
case object NMemoryChannels extends Field[Int]
/** Number of banks per memory channel */
case object NBanksPerMemoryChannel extends Field[Int]
/** Maximum number of banks per memory channel, when configurable */
case object MaxBanksPerMemoryChannel extends Field[Int]
/** Dynamic memory channel configurations */
case object MemoryChannelMuxConfigs extends Field[List[Int]]
/** Least significant bit of address used for bank partitioning */
case object BankIdLSB extends Field[Int]
/** Number of outstanding memory requests */
case object NOutstandingMemReqsPerChannel extends Field[Int]
/** Whether to use the slow backup memory port [VLSI] */
case object UseBackupMemoryPort extends Field[Boolean]
/** Function for building some kind of coherence manager agent */
case object BuildL2CoherenceManager extends Field[(Int, Parameters) => CoherenceAgent]
/** Function for building some kind of tile connected to a reset signal */
case object BuildTiles extends Field[Seq[(Bool, Parameters) => Tile]]
/** Enable DMA engine */
case object UseDma extends Field[Boolean]
case object UseStreamLoopback extends Field[Boolean]
case object StreamLoopbackSize extends Field[Int]
case object StreamLoopbackWidth extends Field[Int]
/** Utility trait for quick access to some relevant parameters */
trait HasTopLevelParameters {
implicit val p: Parameters
lazy val useDma = p(UseDma)
lazy val nTiles = p(NTiles)
lazy val nCachedTilePorts = p(TLKey("L1toL2")).nCachingClients
lazy val nUncachedTilePorts =
p(TLKey("L1toL2")).nCachelessClients - (if (useDma) 2 else 1)
lazy val htifW = p(HtifKey).width
lazy val csrAddrBits = 12
lazy val nMemChannels = p(NMemoryChannels)
lazy val nBanksPerMemChannel = p(NBanksPerMemoryChannel)
lazy val nBanks = nMemChannels*nBanksPerMemChannel
lazy val lsb = p(BankIdLSB)
lazy val nMemReqs = p(NOutstandingMemReqsPerChannel)
lazy val mifAddrBits = p(MIFAddrBits)
lazy val mifDataBeats = p(MIFDataBeats)
lazy val xLen = p(XLen)
lazy val nSCR = p(HtifKey).nSCR
lazy val scrAddrBits = log2Up(nSCR)
lazy val scrDataBits = 64
lazy val scrDataBytes = scrDataBits / 8
lazy val memoryChannelMuxConfigs = p(MemoryChannelMuxConfigs)
//require(lsb + log2Up(nBanks) < mifAddrBits)
}
class MemBackupCtrlIO extends Bundle {
val en = Bool(INPUT)
val in_valid = Bool(INPUT)
val out_ready = Bool(INPUT)
val out_valid = Bool(OUTPUT)
}
/** Top-level io for the chip */
class BasicTopIO(implicit val p: Parameters) extends ParameterizedBundle()(p)
with HasTopLevelParameters {
val host = new HostIO(htifW)
val mem_backup_ctrl = new MemBackupCtrlIO
}
class TopIO(implicit p: Parameters) extends BasicTopIO()(p) {
val mem = Vec(nMemChannels, new NastiIO)
}
object TopUtils {
// Connect two Nasti interfaces with queues in-between
def connectNasti(outer: NastiIO, inner: NastiIO)(implicit p: Parameters) {
val mifDataBeats = p(MIFDataBeats)
outer.ar <> Queue(inner.ar)
outer.aw <> Queue(inner.aw)
outer.w <> Queue(inner.w, mifDataBeats)
inner.r <> Queue(outer.r, mifDataBeats)
inner.b <> Queue(outer.b)
}
}
/** Top-level module for the chip */
//TODO: Remove this wrapper once multichannel DRAM controller is provided
class Top(topParams: Parameters) extends Module with HasTopLevelParameters {
implicit val p = topParams
val io = new TopIO
// Build an Uncore and a set of Tiles
val innerTLParams = p.alterPartial({case TLId => "L1toL2" })
val uncore = Module(new Uncore()(innerTLParams))
val tileList = uncore.io.htif zip p(BuildTiles) map { case(hl, bt) => bt(hl.reset, p) }
// Connect each tile to the HTIF
uncore.io.htif.zip(tileList).zipWithIndex.foreach {
case ((hl, tile), i) =>
tile.io.host.id := UInt(i)
tile.io.host.reset := Reg(next=Reg(next=hl.reset))
tile.io.host.csr.req <> Queue(hl.csr.req)
hl.csr.resp <> Queue(tile.io.host.csr.resp)
hl.debug_stats_csr := tile.io.host.debug_stats_csr
}
// 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
io.host <> uncore.io.host
if (p(UseBackupMemoryPort)) { io.mem_backup_ctrl <> uncore.io.mem_backup_ctrl }
io.mem.zip(uncore.io.mem).foreach { case (outer, inner) =>
TopUtils.connectNasti(outer, inner)
// Memory cache type should be normal non-cacheable bufferable
outer.ar.bits.cache := UInt("b0011")
outer.aw.bits.cache := UInt("b0011")
}
}
/** Wrapper around everything that isn't a Tile.
*
* Usually this is clocked and/or place-and-routed separately from the Tiles.
* Contains the Host-Target InterFace module (HTIF).
*/
class Uncore(implicit val p: Parameters) extends Module
with HasTopLevelParameters {
val io = new Bundle {
val host = new HostIO(htifW)
val mem = Vec(nMemChannels, new NastiIO)
val tiles_cached = Vec(nCachedTilePorts, new ClientTileLinkIO).flip
val tiles_uncached = Vec(nUncachedTilePorts, new ClientUncachedTileLinkIO).flip
val htif = Vec(nTiles, new HtifIO).flip
val mem_backup_ctrl = new MemBackupCtrlIO
val mmio = new NastiIO
}
val htif = Module(new Htif(CSRs.mreset)) // One HTIF module per chip
val outmemsys = Module(new OuterMemorySystem) // NoC, LLC and SerDes
outmemsys.io.incoherent := htif.io.cpu.map(_.reset)
outmemsys.io.htif_uncached <> htif.io.mem
outmemsys.io.tiles_uncached <> io.tiles_uncached
outmemsys.io.tiles_cached <> io.tiles_cached
for (i <- 0 until nTiles) {
io.htif(i).reset := htif.io.cpu(i).reset
io.htif(i).id := htif.io.cpu(i).id
htif.io.cpu(i).debug_stats_csr <> io.htif(i).debug_stats_csr
val csr_arb = Module(new SmiArbiter(2, xLen, csrAddrBits))
csr_arb.io.in(0) <> htif.io.cpu(i).csr
csr_arb.io.in(1) <> outmemsys.io.csr(i)
io.htif(i).csr <> csr_arb.io.out
}
// Arbitrate SCR access between MMIO and HTIF
val scrFile = Module(new SCRFile("UNCORE_SCR"))
val scrArb = Module(new SmiArbiter(2, scrDataBits, scrAddrBits))
scrArb.io.in(0) <> htif.io.scr
scrArb.io.in(1) <> outmemsys.io.scr
scrFile.io.smi <> scrArb.io.out
// scrFile.io.scr <> (... your SCR connections ...)
// Configures the enabled memory channels. This can't be changed while the
// chip is actively using memory, as it both drops Nasti messages and garbles
// all of memory.
val memory_channel_mux_select = scrFile.io.scr.attach(
Reg(UInt(width = log2Up(memoryChannelMuxConfigs.size))),
"MEMORY_CHANNEL_MUX_SELECT")
outmemsys.io.memory_channel_mux_select := memory_channel_mux_select
val deviceTree = Module(new NastiROM(p(DeviceTree).toSeq))
deviceTree.io <> outmemsys.io.deviceTree
// Wire the htif to the memory port(s) and host interface
io.host.debug_stats_csr := htif.io.host.debug_stats_csr
io.mem <> outmemsys.io.mem
if(p(UseBackupMemoryPort)) {
outmemsys.io.mem_backup_en := io.mem_backup_ctrl.en
VLSIUtils.padOutHTIFWithDividedClock(htif.io.host, scrFile.io.scr,
outmemsys.io.mem_backup, io.mem_backup_ctrl, io.host, htifW)
} else {
htif.io.host.out <> io.host.out
htif.io.host.in <> io.host.in
}
}
/** The whole outer memory hierarchy, including a NoC, some kind of coherence
* manager agent, and a converter from TileLink to MemIO.
*/
class OuterMemorySystem(implicit val p: Parameters) extends Module with HasTopLevelParameters {
val io = new Bundle {
val tiles_cached = Vec(nCachedTilePorts, new ClientTileLinkIO).flip
val tiles_uncached = Vec(nUncachedTilePorts, new ClientUncachedTileLinkIO).flip
val htif_uncached = (new ClientUncachedTileLinkIO).flip
val incoherent = Vec(nTiles, Bool()).asInput
val mem = Vec(nMemChannels, new NastiIO)
val mem_backup = new MemSerializedIO(htifW)
val mem_backup_en = Bool(INPUT)
val memory_channel_mux_select = UInt(INPUT, log2Up(memoryChannelMuxConfigs.size))
val csr = Vec(nTiles, new SmiIO(xLen, csrAddrBits))
val scr = new SmiIO(xLen, scrAddrBits)
val deviceTree = new NastiIO
}
val dmaOpt = if (p(UseDma))
Some(Module(new DmaEngine(
DmaCtrlRegNumbers.CSR_BASE + DmaCtrlRegNumbers.OUTSTANDING)))
else None
val mmioBase = p(MMIOBase)
// Create a simple L1toL2 NoC between the tiles+htif and the banks of outer memory
// Cached ports are first in client list, making sharerToClientId just an indentity function
// addrToBank is sed to hash physical addresses (of cache blocks) to banks (and thereby memory channels)
val ordered_clients = (io.tiles_cached ++
(io.tiles_uncached ++ dmaOpt.map(_.io.mem) :+ io.htif_uncached)
.map(TileLinkIOWrapper(_)))
def sharerToClientId(sharerId: UInt) = sharerId
def addrToBank(addr: Bits): UInt = {
Mux(addr.toUInt < UInt(mmioBase >> log2Up(p(CacheBlockBytes))),
if (nBanks > 1) addr(lsb + log2Up(nBanks) - 1, lsb) else UInt(0),
UInt(nBanks))
}
val preBuffering = TileLinkDepths(2,2,2,2,2)
val postBuffering = TileLinkDepths(0,0,1,0,0) //TODO: had EOS24 crit path on inner.release
val l1tol2net = Module(new RocketChipTileLinkCrossbar(addrToBank, sharerToClientId, preBuffering, postBuffering))
// Create point(s) of coherence serialization
val managerEndpoints = List.tabulate(nBanks){id => p(BuildL2CoherenceManager)(id, p)}
managerEndpoints.foreach { _.incoherent := io.incoherent }
val mmioManager = Module(new MMIOTileLinkManager()(p.alterPartial({
case TLId => "L1toL2"
case InnerTLId => "L1toL2"
case OuterTLId => "L2toMC"
})))
// Wire the tiles and htif to the TileLink client ports of the L1toL2 network,
// and coherence manager(s) to the other side
l1tol2net.io.clients <> ordered_clients
l1tol2net.io.managers <> managerEndpoints.map(_.innerTL) :+ mmioManager.io.inner
// Create a converter between TileLinkIO and MemIO for each channel
val outerTLParams = p.alterPartial({ case TLId => "L2toMC" })
val outermostTLParams = p.alterPartial({case TLId => "Outermost"})
val backendBuffering = TileLinkDepths(0,0,0,0,0)
val addrMap = p(GlobalAddrMap)
val addrHashMap = new AddrHashMap(addrMap, mmioBase)
val nMasters = (if (dmaOpt.isEmpty) 2 else 3)
val nSlaves = addrHashMap.nEntries
println("Generated Address Map")
for ((name, base, size, _) <- addrHashMap.sortedEntries) {
println(f"\t$name%s $base%x - ${base + size - 1}%x")
}
val mmio_ic = Module(new NastiRecursiveInterconnect(nMasters, nSlaves, addrMap, mmioBase))
val channelConfigs = p(MemoryChannelMuxConfigs)
Predef.assert(channelConfigs.sortWith(_ > _)(0) == nMemChannels,
"More memory channels elaborated than can be enabled")
val mem_ic =
if (channelConfigs.size == 1) {
val ic = Module(new NastiMemoryInterconnect(nBanksPerMemChannel, nMemChannels))
ic
} else {
val nBanks = nBanksPerMemChannel * nMemChannels
val ic = Module(new NastiMemorySelector(nBanks, nMemChannels, channelConfigs))
ic.io.select := io.memory_channel_mux_select
ic
}
for ((bank, i) <- managerEndpoints.zipWithIndex) {
val unwrap = Module(new ClientTileLinkIOUnwrapper()(outerTLParams))
val narrow = Module(new TileLinkIONarrower("L2toMC", "Outermost"))
val conv = Module(new NastiIOTileLinkIOConverter()(outermostTLParams))
unwrap.io.in <> ClientTileLinkEnqueuer(bank.outerTL, backendBuffering)(outerTLParams)
narrow.io.in <> unwrap.io.out
conv.io.tl <> narrow.io.out
TopUtils.connectNasti(mem_ic.io.masters(i), conv.io.nasti)
}
val mmio_narrow = Module(new TileLinkIONarrower("L2toMC", "Outermost"))
val mmio_conv = Module(new NastiIOTileLinkIOConverter()(outermostTLParams))
mmio_narrow.io.in <> mmioManager.io.outer
mmio_conv.io.tl <> mmio_narrow.io.out
TopUtils.connectNasti(mmio_ic.io.masters(0), mmio_conv.io.nasti)
val rtc = Module(new RTC(CSRs.mtime))
mmio_ic.io.masters(1) <> rtc.io
dmaOpt.foreach { dma =>
mmio_ic.io.masters(2) <> dma.io.mmio
dma.io.ctrl <> mmio_ic.io.slaves(addrHashMap("devices:dma").port)
}
for (i <- 0 until nTiles) {
val csrName = s"conf:csr$i"
val csrPort = addrHashMap(csrName).port
val conv = Module(new SmiIONastiIOConverter(xLen, csrAddrBits))
conv.io.nasti <> mmio_ic.io.slaves(csrPort)
io.csr(i) <> conv.io.smi
}
val scr_conv = Module(new SmiIONastiIOConverter(scrDataBits, scrAddrBits))
scr_conv.io.nasti <> mmio_ic.io.slaves(addrHashMap("conf:scr").port)
io.scr <> scr_conv.io.smi
if (p(UseStreamLoopback)) {
val lo_width = p(StreamLoopbackWidth)
val lo_size = p(StreamLoopbackSize)
val lo_conv = Module(new NastiIOStreamIOConverter(lo_width))
lo_conv.io.nasti <> mmio_ic.io.slaves(addrHashMap("devices:loopback").port)
lo_conv.io.stream.in <> Queue(lo_conv.io.stream.out, lo_size)
}
io.deviceTree <> mmio_ic.io.slaves(addrHashMap("conf:devicetree").port)
val mem_channels = mem_ic.io.slaves
// Create a SerDes for backup memory port
if(p(UseBackupMemoryPort)) {
VLSIUtils.doOuterMemorySystemSerdes(
mem_channels, io.mem, io.mem_backup, io.mem_backup_en,
nMemChannels, htifW, p(CacheBlockOffsetBits))
} else { io.mem <> mem_channels }
}