riscv/rocket-chip
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rocket scratchpad: support atomics

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This commit is contained in:
Wesley W. Terpstra 2016-10-28 12:13:01 -07:00
parent 0cc00e7616
commit 92ee498521
2 changed files with 32 additions and 18 deletions
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48
src/main/scala/rocket/dcache.scala
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@ -498,17 +498,18 @@ class DCache(implicit p: Parameters) extends L1HellaCacheModule()(p) {
}
class ScratchpadSlavePort(implicit val p: Parameters) extends LazyModule with HasCoreParameters {
val beatBytes = p(XLen)/8
val node = TLManagerNode(TLManagerPortParameters(
Seq(TLManagerParameters(
address = List(AddressSet(0x80000000L, BigInt(p(DataScratchpadSize)-1))),
regionType = RegionType.UNCACHED,
executable = true,
supportsPutPartial = TransferSizes(1, beatBytes),
supportsPutFull = TransferSizes(1, beatBytes),
supportsGet = TransferSizes(1, beatBytes),
supportsArithmetic = if (p(UseAtomics)) TransferSizes(1, coreDataBytes) else TransferSizes.none,
supportsLogical = if (p(UseAtomics)) TransferSizes(1, coreDataBytes) else TransferSizes.none,
supportsPutPartial = TransferSizes(1, coreDataBytes),
supportsPutFull = TransferSizes(1, coreDataBytes),
supportsGet = TransferSizes(1, coreDataBytes),
fifoId = Some(0))), // requests handled in FIFO order
beatBytes = beatBytes,
beatBytes = coreDataBytes,
minLatency = 1))
// Make sure this ends up with the same name as before
@ -522,9 +523,7 @@ class ScratchpadSlavePort(implicit val p: Parameters) extends LazyModule with Ha
val tl_in = io.tl_in(0)
val edge = node.edgesIn(0)
val beatBytes = edge.manager.beatBytes
require(coreDataBits == beatBytes*8)
require(usingDataScratchpad)
val s_ready :: s_wait :: s_replay :: s_grant :: Nil = Enum(UInt(), 4)
@ -538,15 +537,29 @@ class ScratchpadSlavePort(implicit val p: Parameters) extends LazyModule with Ha
when (io.dmem.resp.valid) { acq.data := io.dmem.resp.bits.data }
when (tl_in.a.fire()) { acq := tl_in.a.bits }
val isWrite = edge.hasData(acq)
val isRead = !isWrite
val isWrite = acq.opcode === TLMessages.PutFullData || acq.opcode === TLMessages.PutPartialData
val isRead = !edge.hasData(acq)
def formCacheReq(acq: TLBundleA) = {
val req = Wire(new HellaCacheReq)
req.cmd := MuxLookup(acq.opcode, Wire(M_XRD), Array(
TLMessages.PutFullData -> M_XWR,
TLMessages.PutPartialData -> M_XWR,
TLMessages.ArithmeticData -> MuxLookup(acq.param, Wire(M_XRD), Array(
TLAtomics.MIN -> M_XA_MIN,
TLAtomics.MAX -> M_XA_MAX,
TLAtomics.MINU -> M_XA_MINU,
TLAtomics.MAXU -> M_XA_MAXU,
TLAtomics.ADD -> M_XA_ADD)),
TLMessages.LogicalData -> MuxLookup(acq.param, Wire(M_XRD), Array(
TLAtomics.XOR -> M_XA_XOR,
TLAtomics.OR -> M_XA_OR,
TLAtomics.AND -> M_XA_AND,
TLAtomics.SWAP -> M_XA_SWAP)),
TLMessages.Get -> M_XRD))
// treat all loads as full words, so bytes appear in correct lane
req.typ := Mux(isRead, log2Ceil(beatBytes), acq.size)
req.cmd := Mux(isRead, M_XRD, M_XWR)
req.addr := Mux(isRead, ~(~acq.address | (beatBytes-1)), acq.address)
req.typ := Mux(isRead, log2Ceil(coreDataBytes), acq.size)
req.addr := Mux(isRead, ~(~acq.address | (coreDataBytes-1)), acq.address)
req.tag := UInt(0)
req
}
@ -555,9 +568,9 @@ class ScratchpadSlavePort(implicit val p: Parameters) extends LazyModule with Ha
io.dmem.req.valid := (tl_in.a.valid && ready) || state === s_replay
tl_in.a.ready := io.dmem.req.ready && ready
io.dmem.req.bits := formCacheReq(Mux(state === s_replay, acq, tl_in.a.bits))
// this blows. the TL data is already in the correct byte lane, but the D$
// the TL data is already in the correct byte lane, but the D$
// expects right-justified store data, so that it can steer the bytes.
io.dmem.s1_data := new LoadGen(acq.size, Bool(false), acq.address(log2Ceil(beatBytes)-1,0), acq.data, Bool(false), beatBytes).data
io.dmem.s1_data := new LoadGen(acq.size, Bool(false), acq.address(log2Ceil(coreDataBytes)-1,0), acq.data, Bool(false), coreDataBytes).data
io.dmem.s1_kill := false
io.dmem.invalidate_lr := false
@ -567,9 +580,10 @@ class ScratchpadSlavePort(implicit val p: Parameters) extends LazyModule with Ha
val alignedGrantData = Mux(acq.size <= log2Ceil(minAMOBytes), Fill(coreDataBytes/minAMOBytes, grantData(8*minAMOBytes-1, 0)), grantData)
tl_in.d.valid := io.dmem.resp.valid || state === s_grant
tl_in.d.bits := Mux(isRead,
edge.AccessAck(acq, UInt(0), alignedGrantData),
edge.AccessAck(acq, UInt(0)))
tl_in.d.bits := Mux(isWrite,
edge.AccessAck(acq, UInt(0)),
edge.AccessAck(acq, UInt(0), UInt(0)))
tl_in.d.bits.data := alignedGrantData
// Tie off unused channels
tl_in.b.valid := Bool(false)

2
src/main/scala/rocket/tile.scala
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@ -61,7 +61,7 @@ class RocketTile(implicit p: Parameters) extends LazyTile {
val slave = if (p(DataScratchpadSize) == 0) None else Some(TLInputNode())
val scratch = if (p(DataScratchpadSize) == 0) None else Some(LazyModule(new ScratchpadSlavePort()(dcacheParams)))
(slave zip scratch) foreach { case (node, lm) => lm.node := TLFragmenter(p(XLen)/8, 256)(node) }
(slave zip scratch) foreach { case (node, lm) => lm.node := TLFragmenter(p(XLen)/8, p(CacheBlockBytes))(node) }
lazy val module = new TileImp(this) {
val io = new TileIO(bc, slave)