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rocket-chip/uncore/coherence.scala
2012-04-09 23:29:31 -07:00

241 lines
9.2 KiB
Scala

package rocket
import Chisel._
import Constants._
class TransactionInit extends Bundle {
val x_type = Bits(width = X_INIT_TYPE_BITS)
val tile_xact_id = Bits(width = TILE_XACT_ID_BITS)
val address = UFix(width = PADDR_BITS - OFFSET_BITS)
}
class TransactionInitData extends MemData
class TransactionAbort extends Bundle {
val tile_xact_id = Bits(width = TILE_XACT_ID_BITS)
}
class ProbeRequest extends Bundle {
val p_type = Bits(width = P_REQ_TYPE_BITS)
val global_xact_id = Bits(width = GLOBAL_XACT_ID_BITS)
val address = Bits(width = PADDR_BITS - OFFSET_BITS)
}
class ProbeReply extends Bundle {
val p_type = Bits(width = P_REP_TYPE_BITS)
val global_xact_id = Bits(width = GLOBAL_XACT_ID_BITS)
}
class ProbeReplyData extends MemData
class TransactionReply extends MemData {
val x_type = Bits(width = X_REP_TYPE_BITS)
val tile_xact_id = Bits(width = TILE_XACT_ID_BITS)
val global_xact_id = Bits(width = GLOBAL_XACT_ID_BITS)
val require_ack = Bool()
}
class TransactionFinish extends Bundle {
val global_xact_id = Bits(width = GLOBAL_XACT_ID_BITS)
}
object cpuCmdToRW {
def apply(cmd: Bits): (Bool, Bool) = {
val store = (cmd === M_XWR)
val load = (cmd === M_XRD)
val amo = cmd(3).toBool
val read = load || amo || (cmd === M_PFR) || (cmd === M_PFW)
val write = store || amo
(read, write)
}
}
trait CoherencePolicy { }
trait ThreeStateIncoherence extends CoherencePolicy {
val tileInvalid :: tileClean :: tileDirty :: Nil = Enum(3){ UFix() }
val xactInitReadShared = UFix(0, 2)
val xactInitReadExclusive = UFix(1, 2)
val xactInitWriteUncached = UFix(3, 2)
val xactReplyReadShared = UFix(0, X_REP_TYPE_BITS)
val xactReplyReadExclusive = UFix(1, X_REP_TYPE_BITS)
val xactReplyWriteUncached = UFix(3, X_REP_TYPE_BITS)
val probeRepInvalidateAck = UFix(3, P_REP_TYPE_BITS)
def isHit ( cmd: Bits, state: UFix): Bool = {
val (read, write) = cpuCmdToRW(cmd)
( state === tileClean || state === tileDirty)
}
def isValid (state: UFix): Bool = {
state != tileInvalid
}
def needsWriteback (state: UFix): Bool = {
state === tileDirty
}
def newStateOnWriteback() = tileInvalid
def newStateOnCacheControl(cmd: Bits) = tileInvalid
def newState(cmd: Bits, state: UFix): UFix = {
val (read, write) = cpuCmdToRW(cmd)
Mux(write, tileDirty, Mux(read, Mux(state === tileDirty, tileDirty, tileClean), state))
}
def newStateOnHit(cmd: Bits, state: UFix): UFix = newState(cmd, state)
def getTransactionInitTypeOnPrimaryMiss(cmd: Bits, state: UFix): UFix = {
val (read, write) = cpuCmdToRW(cmd)
Mux(write || cmd === M_PFW, xactInitReadExclusive, xactInitReadShared)
}
def getTransactionInitTypeOnSecondaryMiss(cmd: Bits, state: UFix, outstanding: TransactionInit): UFix = {
val (read, write) = cpuCmdToRW(cmd)
Mux(write, xactInitReadExclusive, outstanding.x_type)
}
def needsTransactionOnSecondaryMiss(cmd: Bits, outstanding: TransactionInit): Bool = Bool(false)
def newStateOnTransactionReply(incoming: TransactionReply, outstanding: TransactionInit): UFix = {
Mux(outstanding.x_type === xactInitReadExclusive, tileDirty, tileClean)
}
def newStateOnProbeRequest(incoming: ProbeRequest, state: UFix): Bits = state
def newProbeReply (incoming: ProbeRequest, has_data: Bool): ProbeReply = {
val reply = Wire() { new ProbeReply() }
reply.p_type := probeRepInvalidateAck
reply.global_xact_id := UFix(0)
reply
}
def probeReplyHasData (reply: ProbeReply): Bool = Bool(false)
def transactionInitHasData (init: TransactionInit): Bool = (init.x_type === xactInitWriteUncached)
}
trait FourStateCoherence extends CoherencePolicy {
val tileInvalid :: tileShared :: tileExclusiveClean :: tileExclusiveDirty :: Nil = Enum(4){ UFix() }
val globalInvalid :: globalShared :: globalExclusiveClean :: Nil = Enum(3){ UFix() }
val xactInitReadShared :: xactInitReadExclusive :: xactInitReadUncached :: xactInitWriteUncached :: Nil = Enum(4){ UFix() }
val xactReplyReadShared :: xactReplyReadExclusive :: xactReplyReadUncached :: xactReplyWriteUncached :: xactReplyReadExclusiveAck :: Nil = Enum(5){ UFix() }
val probeReqInvalidate :: probeReqDowngrade :: probeReqCopy :: Nil = Enum(3){ UFix() }
val probeRepInvalidateData :: probeRepDowngradeData :: probeRepCopyData :: probeRepInvalidateAck :: probeRepDowngradeAck :: probeRepCopyAck :: Nil = Enum(6){ UFix() }
def isHit (cmd: Bits, state: UFix): Bool = {
val (read, write) = cpuCmdToRW(cmd)
Mux(write, (state === tileExclusiveClean || state === tileExclusiveDirty),
(state === tileShared || state === tileExclusiveClean || state === tileExclusiveDirty))
}
def isValid (state: UFix): Bool = {
state != tileInvalid
}
def needsTransactionOnSecondaryMiss(cmd: Bits, outstanding: TransactionInit): Bool = {
val (read, write) = cpuCmdToRW(cmd)
(read && (outstanding.x_type === xactInitReadUncached || outstanding.x_type === xactInitWriteUncached)) ||
(write && (outstanding.x_type != xactInitReadExclusive))
}
def needsTransactionOnCacheControl(cmd: Bits, state: UFix): Bool = {
MuxLookup(cmd, (state === tileExclusiveDirty), Array(
M_INV -> (state === tileExclusiveDirty),
M_CLN -> (state === tileExclusiveDirty)
))
}
def needsWriteback (state: UFix): Bool = {
needsTransactionOnCacheControl(M_INV, state)
}
def newStateOnHit(cmd: Bits, state: UFix): UFix = {
val (read, write) = cpuCmdToRW(cmd)
Mux(write, tileExclusiveDirty, state)
}
def newStateOnCacheControl(cmd: Bits) = {
MuxLookup(cmd, tileInvalid, Array(
M_INV -> tileInvalid,
M_CLN -> tileExclusiveClean
))
}
def newStateOnWriteback() = newStateOnCacheControl(M_INV)
def newStateOnFlush() = newStateOnCacheControl(M_INV)
def newStateOnTransactionReply(incoming: TransactionReply, outstanding: TransactionInit): UFix = {
MuxLookup(incoming.x_type, tileInvalid, Array(
xactReplyReadShared -> tileShared,
xactReplyReadExclusive -> Mux(outstanding.x_type === xactInitReadExclusive, tileExclusiveDirty, tileExclusiveClean),
xactReplyReadExclusiveAck -> tileExclusiveDirty,
xactReplyReadUncached -> tileInvalid,
xactReplyWriteUncached -> tileInvalid
))
}
def newStateOnProbeRequest(incoming: ProbeRequest, state: UFix): Bits = {
MuxLookup(incoming.p_type, state, Array(
probeReqInvalidate -> tileInvalid,
probeReqDowngrade -> tileShared,
probeReqCopy -> state
))
}
def getTransactionInitTypeOnPrimaryMiss(cmd: Bits, state: UFix): UFix = {
val (read, write) = cpuCmdToRW(cmd)
Mux(write || cmd === M_PFW, xactInitReadExclusive, xactInitReadShared)
}
def getTransactionInitTypeOnSecondaryMiss(cmd: Bits, state: UFix, outstanding: TransactionInit): UFix = {
val (read, write) = cpuCmdToRW(cmd)
Mux(write, xactInitReadExclusive, outstanding.x_type)
}
def getTransactionInitTypeOnCacheControl(cmd: Bits): Bits = xactInitWriteUncached
def getTransactionInitTypeOnWriteback(): Bits = getTransactionInitTypeOnCacheControl(M_INV)
def newProbeReply (incoming: ProbeRequest, state: UFix): ProbeReply = {
val reply = Wire() { new ProbeReply() }
val with_data = MuxLookup(incoming.p_type, probeRepInvalidateData, Array(
probeReqInvalidate -> probeRepInvalidateData,
probeReqDowngrade -> probeRepDowngradeData,
probeReqCopy -> probeRepCopyData
))
val without_data = MuxLookup(incoming.p_type, probeRepInvalidateAck, Array(
probeReqInvalidate -> probeRepInvalidateAck,
probeReqDowngrade -> probeRepDowngradeAck,
probeReqCopy -> probeRepCopyAck
))
reply.p_type := Mux(needsWriteback(state), with_data, without_data)
reply.global_xact_id := incoming.global_xact_id
reply
}
def hasData (reply: ProbeReply): Bool = {
(reply.p_type === probeRepInvalidateData ||
reply.p_type === probeRepDowngradeData ||
reply.p_type === probeRepCopyData)
}
def hasData (init: TransactionInit): Bool = {
(init.x_type === xactInitWriteUncached)
}
def hasData (reply: TransactionReply): Bool = {
(reply.x_type != xactReplyWriteUncached && reply.x_type != xactReplyReadExclusiveAck)
}
def isCoherenceConflict(addr1: Bits, addr2: Bits): Bool = (addr1 === addr2)
def getTransactionReplyType(x_type: UFix, count: UFix): Bits = {
MuxLookup(x_type, xactReplyReadUncached, Array(
xactInitReadShared -> Mux(count > UFix(0), xactReplyReadShared, xactReplyReadExclusive),
xactInitReadExclusive -> xactReplyReadExclusive,
xactInitReadUncached -> xactReplyReadUncached,
xactInitWriteUncached -> xactReplyWriteUncached
))
}
def getProbeRequestType(x_type: UFix, global_state: UFix): UFix = {
MuxLookup(x_type, probeReqCopy, Array(
xactInitReadShared -> probeReqDowngrade,
xactInitReadExclusive -> probeReqInvalidate,
xactInitReadUncached -> probeReqCopy,
xactInitWriteUncached -> probeReqInvalidate
))
}
def needsMemRead(x_type: UFix, global_state: UFix): Bool = {
(x_type != xactInitWriteUncached)
}
def needsMemWrite(x_type: UFix, global_state: UFix): Bool = {
(x_type === xactInitWriteUncached)
}
def needsAckReply(x_type: UFix, global_state: UFix): Bool = {
(x_type === xactInitWriteUncached)
}
}