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rocket-chip/uncore/src/main/scala/coherence.scala
2016-01-14 14:55:45 -08:00

690 lines
32 KiB
Scala

// See LICENSE for license details.
package uncore
import Chisel._
/** The entire CoherencePolicy API consists of the following three traits:
* HasCustomTileLinkMessageTypes, used to define custom messages
* HasClientSideCoherencePolicy, for client coherence agents
* HasManagerSideCoherencePolicy, for manager coherence agents
*/
abstract class CoherencePolicy(val dir: DirectoryRepresentation)
extends HasCustomTileLinkMessageTypes
with HasClientSideCoherencePolicy
with HasManagerSideCoherencePolicy
/** This API defines the custom, coherence-policy-defined message types,
* as opposed to the built-in ones found in tilelink.scala.
* Policies must enumerate the custom messages to be sent over each
* channel, as well as which of them have associated data.
*/
trait HasCustomTileLinkMessageTypes {
val nAcquireTypes: Int
def acquireTypeWidth = log2Up(nAcquireTypes)
val nProbeTypes: Int
def probeTypeWidth = log2Up(nProbeTypes)
val nReleaseTypes: Int
def releaseTypeWidth = log2Up(nReleaseTypes)
val nGrantTypes: Int
def grantTypeWidth = log2Up(nGrantTypes)
val acquireTypesWithData = Nil // Only built-in Acquire types have data for now
def releaseTypesWithData: Vec[UInt]
def grantTypesWithData: Vec[UInt]
}
/** This API contains all functions required for client coherence agents.
* Policies must enumerate the number of client states and define their
* permissions with respect to memory operations. Policies must fill in functions
* to control which messages are sent and how metadata is updated in response
* to coherence events. These funtions are generally called from within the
* ClientMetadata class in metadata.scala
*/
trait HasClientSideCoherencePolicy {
// Client coherence states and their permissions
val nClientStates: Int
def clientStateWidth = log2Ceil(nClientStates)
def clientStatesWithReadPermission: Vec[UInt]
def clientStatesWithWritePermission: Vec[UInt]
def clientStatesWithDirtyData: Vec[UInt]
// Transaction initiation logic
def isValid(meta: ClientMetadata): Bool
def isHit(cmd: UInt, meta: ClientMetadata): Bool = {
Mux(isWriteIntent(cmd),
clientStatesWithWritePermission.contains(meta.state),
clientStatesWithReadPermission.contains(meta.state))
}
//TODO: Assumes all states with write permissions also have read permissions
def requiresAcquireOnSecondaryMiss(
first_cmd: UInt,
second_cmd: UInt,
meta: ClientMetadata): Bool = {
isWriteIntent(second_cmd) && !isWriteIntent(first_cmd)
}
//TODO: Assumes all cache ctrl ops writeback dirty data, and
// doesn't issue transaction when e.g. downgrading Exclusive to Shared:
def requiresReleaseOnCacheControl(cmd: UInt, meta: ClientMetadata): Bool =
clientStatesWithDirtyData.contains(meta.state)
// Determine which custom message type to use
def getAcquireType(cmd: UInt, meta: ClientMetadata): UInt
def getReleaseType(cmd: UInt, meta: ClientMetadata): UInt
def getReleaseType(p: HasProbeType, meta: ClientMetadata): UInt
// Mutate ClientMetadata based on messages or cmds
def clientMetadataOnHit(cmd: UInt, meta: ClientMetadata): ClientMetadata
def clientMetadataOnCacheControl(cmd: UInt, meta: ClientMetadata): ClientMetadata
def clientMetadataOnGrant(incoming: HasGrantType, cmd: UInt, meta: ClientMetadata): ClientMetadata
def clientMetadataOnProbe(incoming: HasProbeType, meta: ClientMetadata): ClientMetadata
}
/** This API contains all functions required for manager coherence agents.
* Policies must enumerate the number of manager states. Policies must fill
* in functions to control which Probe and Grant messages are sent and how
* metadata should be updated in response to coherence events. These funtions
* are generally called from within the ManagerMetadata class in metadata.scala
*/
trait HasManagerSideCoherencePolicy extends HasDirectoryRepresentation {
val nManagerStates: Int
def masterStateWidth = log2Ceil(nManagerStates)
// Transaction probing logic
def requiresProbes(acq: HasAcquireType, meta: ManagerMetadata): Bool
def requiresProbes(cmd: UInt, meta: ManagerMetadata): Bool
// Determine which custom message type to use in response
def getProbeType(cmd: UInt, meta: ManagerMetadata): UInt
def getProbeType(acq: HasAcquireType, meta: ManagerMetadata): UInt
def getGrantType(acq: HasAcquireType, meta: ManagerMetadata): UInt
def getExclusiveGrantType(): UInt
// Mutate ManagerMetadata based on messages or cmds
def managerMetadataOnRelease(incoming: HasReleaseType, src: UInt, meta: ManagerMetadata): ManagerMetadata
def managerMetadataOnGrant(outgoing: HasGrantType, dst: UInt, meta: ManagerMetadata) =
ManagerMetadata(sharers=Mux(outgoing.isBuiltInType(), // Assumes all built-ins are uncached
meta.sharers,
dir.push(meta.sharers, dst)))(meta.p)
//state = meta.state) TODO: Fix 0-width wires in Chisel
}
/** The following concrete implementations of CoherencePolicy each provide the
* functionality of one particular protocol.
*/
/** A simple protocol with only two Client states.
* Data is always assumed to be dirty.
* Only a single client may ever have a copy of a block at a time.
*/
class MICoherence(dir: DirectoryRepresentation) extends CoherencePolicy(dir) {
// Message types
val nAcquireTypes = 1
val nProbeTypes = 2
val nReleaseTypes = 4
val nGrantTypes = 1
val acquireExclusive :: Nil = Enum(UInt(), nAcquireTypes)
val probeInvalidate :: probeCopy :: Nil = Enum(UInt(), nProbeTypes)
val releaseInvalidateData :: releaseCopyData :: releaseInvalidateAck :: releaseCopyAck :: Nil = Enum(UInt(), nReleaseTypes)
val grantExclusive :: Nil = Enum(UInt(), nGrantTypes)
def releaseTypesWithData = Vec(releaseInvalidateData, releaseCopyData)
def grantTypesWithData = Vec(grantExclusive)
// Client states and functions
val nClientStates = 2
val clientInvalid :: clientValid :: Nil = Enum(UInt(), nClientStates)
def clientStatesWithReadPermission = Vec(clientValid)
def clientStatesWithWritePermission = Vec(clientValid)
def clientStatesWithDirtyData = Vec(clientValid)
def isValid (meta: ClientMetadata): Bool = meta.state =/= clientInvalid
def getAcquireType(cmd: UInt, meta: ClientMetadata): UInt = acquireExclusive
def getReleaseType(cmd: UInt, meta: ClientMetadata): UInt = {
val dirty = clientStatesWithDirtyData.contains(meta.state)
MuxLookup(cmd, releaseCopyAck, Array(
M_FLUSH -> Mux(dirty, releaseInvalidateData, releaseInvalidateAck),
M_PRODUCE -> Mux(dirty, releaseCopyData, releaseCopyAck),
M_CLEAN -> Mux(dirty, releaseCopyData, releaseCopyAck)))
}
def getReleaseType(incoming: HasProbeType, meta: ClientMetadata): UInt =
MuxLookup(incoming.p_type, releaseInvalidateAck, Array(
probeInvalidate -> getReleaseType(M_FLUSH, meta),
probeCopy -> getReleaseType(M_CLEAN, meta)))
def clientMetadataOnHit(cmd: UInt, meta: ClientMetadata) = meta
def clientMetadataOnCacheControl(cmd: UInt, meta: ClientMetadata) =
ClientMetadata(Mux(cmd === M_FLUSH, clientInvalid, meta.state))(meta.p)
def clientMetadataOnGrant(incoming: HasGrantType, cmd: UInt, meta: ClientMetadata) =
ClientMetadata(Mux(incoming.isBuiltInType(), clientInvalid, clientValid))(meta.p)
def clientMetadataOnProbe(incoming: HasProbeType, meta: ClientMetadata) =
ClientMetadata(Mux(incoming.p_type === probeInvalidate,
clientInvalid, meta.state))(meta.p)
// Manager states and functions:
val nManagerStates = 0 // We don't actually need any states for this protocol
def requiresProbes(a: HasAcquireType, meta: ManagerMetadata) = !dir.none(meta.sharers)
def requiresProbes(cmd: UInt, meta: ManagerMetadata) = !dir.none(meta.sharers)
def getProbeType(cmd: UInt, meta: ManagerMetadata): UInt =
MuxLookup(cmd, probeCopy, Array(
M_FLUSH -> probeInvalidate))
def getProbeType(a: HasAcquireType, meta: ManagerMetadata): UInt =
Mux(a.isBuiltInType(),
MuxLookup(a.a_type, probeCopy, Array(
Acquire.getBlockType -> probeCopy,
Acquire.putBlockType -> probeInvalidate,
Acquire.getType -> probeCopy,
Acquire.putType -> probeInvalidate,
Acquire.getPrefetchType -> probeCopy,
Acquire.putPrefetchType -> probeInvalidate,
Acquire.putAtomicType -> probeInvalidate)),
probeInvalidate)
def getGrantType(a: HasAcquireType, meta: ManagerMetadata): UInt =
Mux(a.isBuiltInType(), Acquire.getBuiltInGrantType(a.a_type), grantExclusive)
def getExclusiveGrantType(): UInt = grantExclusive
def managerMetadataOnRelease(incoming: HasReleaseType, src: UInt, meta: ManagerMetadata) = {
val popped = ManagerMetadata(sharers=dir.pop(meta.sharers, src))(meta.p)
MuxBundle(meta, Array(
incoming.is(releaseInvalidateData) -> popped,
incoming.is(releaseInvalidateAck) -> popped))
}
}
/** A simple protocol with only three Client states.
* Data is marked as dirty when written.
* Only a single client may ever have a copy of a block at a time.
*/
class MEICoherence(dir: DirectoryRepresentation) extends CoherencePolicy(dir) {
// Message types
val nAcquireTypes = 2
val nProbeTypes = 3
val nReleaseTypes = 6
val nGrantTypes = 1
val acquireExclusiveClean :: acquireExclusiveDirty :: Nil = Enum(UInt(), nAcquireTypes)
val probeInvalidate :: probeDowngrade :: probeCopy :: Nil = Enum(UInt(), nProbeTypes)
val releaseInvalidateData :: releaseDowngradeData :: releaseCopyData :: releaseInvalidateAck :: releaseDowngradeAck :: releaseCopyAck :: Nil = Enum(UInt(), nReleaseTypes)
val grantExclusive :: Nil = Enum(UInt(), nGrantTypes)
def releaseTypesWithData = Vec(releaseInvalidateData, releaseDowngradeData, releaseCopyData)
def grantTypesWithData = Vec(grantExclusive)
// Client states and functions
val nClientStates = 3
val clientInvalid :: clientExclusiveClean :: clientExclusiveDirty :: Nil = Enum(UInt(), nClientStates)
def clientStatesWithReadPermission = Vec(clientExclusiveClean, clientExclusiveDirty)
def clientStatesWithWritePermission = Vec(clientExclusiveClean, clientExclusiveDirty)
def clientStatesWithDirtyData = Vec(clientExclusiveDirty)
def isValid (meta: ClientMetadata) = meta.state =/= clientInvalid
def getAcquireType(cmd: UInt, meta: ClientMetadata): UInt =
Mux(isWriteIntent(cmd), acquireExclusiveDirty, acquireExclusiveClean)
def getReleaseType(cmd: UInt, meta: ClientMetadata): UInt = {
val dirty = clientStatesWithDirtyData.contains(meta.state)
MuxLookup(cmd, releaseCopyAck, Array(
M_FLUSH -> Mux(dirty, releaseInvalidateData, releaseInvalidateAck),
M_PRODUCE -> Mux(dirty, releaseDowngradeData, releaseDowngradeAck),
M_CLEAN -> Mux(dirty, releaseCopyData, releaseCopyAck)))
}
def getReleaseType(incoming: HasProbeType, meta: ClientMetadata): UInt =
MuxLookup(incoming.p_type, releaseInvalidateAck, Array(
probeInvalidate -> getReleaseType(M_FLUSH, meta),
probeDowngrade -> getReleaseType(M_PRODUCE, meta),
probeCopy -> getReleaseType(M_CLEAN, meta)))
def clientMetadataOnHit(cmd: UInt, meta: ClientMetadata) =
ClientMetadata(Mux(isWrite(cmd), clientExclusiveDirty, meta.state))(meta.p)
def clientMetadataOnCacheControl(cmd: UInt, meta: ClientMetadata) =
ClientMetadata(
MuxLookup(cmd, meta.state, Array(
M_FLUSH -> clientInvalid,
M_CLEAN -> Mux(meta.state === clientExclusiveDirty, clientExclusiveClean, meta.state))))(meta.p)
def clientMetadataOnGrant(incoming: HasGrantType, cmd: UInt, meta: ClientMetadata) =
ClientMetadata(
Mux(incoming.isBuiltInType(), clientInvalid,
Mux(isWrite(cmd), clientExclusiveDirty, clientExclusiveClean)))(meta.p)
def clientMetadataOnProbe(incoming: HasProbeType, meta: ClientMetadata) =
ClientMetadata(
MuxLookup(incoming.p_type, meta.state, Array(
probeInvalidate -> clientInvalid,
probeDowngrade -> clientExclusiveClean,
probeCopy -> meta.state)))(meta.p)
// Manager states and functions:
val nManagerStates = 0 // We don't actually need any states for this protocol
def requiresProbes(a: HasAcquireType, meta: ManagerMetadata) = !dir.none(meta.sharers)
def requiresProbes(cmd: UInt, meta: ManagerMetadata) = !dir.none(meta.sharers)
def getProbeType(cmd: UInt, meta: ManagerMetadata): UInt =
MuxLookup(cmd, probeCopy, Array(
M_FLUSH -> probeInvalidate,
M_PRODUCE -> probeDowngrade))
def getProbeType(a: HasAcquireType, meta: ManagerMetadata): UInt =
Mux(a.isBuiltInType(),
MuxLookup(a.a_type, probeCopy, Array(
Acquire.getBlockType -> probeCopy,
Acquire.putBlockType -> probeInvalidate,
Acquire.getType -> probeCopy,
Acquire.putType -> probeInvalidate,
Acquire.getPrefetchType -> probeCopy,
Acquire.putPrefetchType -> probeInvalidate,
Acquire.putAtomicType -> probeInvalidate)),
probeInvalidate)
def getGrantType(a: HasAcquireType, meta: ManagerMetadata): UInt =
Mux(a.isBuiltInType(), Acquire.getBuiltInGrantType(a.a_type), grantExclusive)
def getExclusiveGrantType(): UInt = grantExclusive
def managerMetadataOnRelease(incoming: HasReleaseType, src: UInt, meta: ManagerMetadata) = {
val popped = ManagerMetadata(sharers=dir.pop(meta.sharers, src))(meta.p)
MuxBundle(meta, Array(
incoming.is(releaseInvalidateData) -> popped,
incoming.is(releaseInvalidateAck) -> popped))
}
}
/** A protocol with only three Client states.
* Data is always assumed to be dirty.
* Multiple clients may share read permissions on a block at the same time.
*/
class MSICoherence(dir: DirectoryRepresentation) extends CoherencePolicy(dir) {
// Message types
val nAcquireTypes = 2
val nProbeTypes = 3
val nReleaseTypes = 6
val nGrantTypes = 3
val acquireShared :: acquireExclusive :: Nil = Enum(UInt(), nAcquireTypes)
val probeInvalidate :: probeDowngrade :: probeCopy :: Nil = Enum(UInt(), nProbeTypes)
val releaseInvalidateData :: releaseDowngradeData :: releaseCopyData :: releaseInvalidateAck :: releaseDowngradeAck :: releaseCopyAck :: Nil = Enum(UInt(), nReleaseTypes)
val grantShared :: grantExclusive :: grantExclusiveAck :: Nil = Enum(UInt(), nGrantTypes)
def releaseTypesWithData = Vec(releaseInvalidateData, releaseDowngradeData, releaseCopyData)
def grantTypesWithData = Vec(grantShared, grantExclusive)
// Client states and functions
val nClientStates = 3
val clientInvalid :: clientShared :: clientExclusiveDirty :: Nil = Enum(UInt(), nClientStates)
def clientStatesWithReadPermission = Vec(clientShared, clientExclusiveDirty)
def clientStatesWithWritePermission = Vec(clientExclusiveDirty)
def clientStatesWithDirtyData = Vec(clientExclusiveDirty)
def isValid(meta: ClientMetadata): Bool = meta.state =/= clientInvalid
def getAcquireType(cmd: UInt, meta: ClientMetadata): UInt =
Mux(isWriteIntent(cmd), acquireExclusive, acquireShared)
def getReleaseType(cmd: UInt, meta: ClientMetadata): UInt = {
val dirty = clientStatesWithDirtyData.contains(meta.state)
MuxLookup(cmd, releaseCopyAck, Array(
M_FLUSH -> Mux(dirty, releaseInvalidateData, releaseInvalidateAck),
M_PRODUCE -> Mux(dirty, releaseDowngradeData, releaseDowngradeAck),
M_CLEAN -> Mux(dirty, releaseCopyData, releaseCopyAck)))
}
def getReleaseType(incoming: HasProbeType, meta: ClientMetadata): UInt =
MuxLookup(incoming.p_type, releaseInvalidateAck, Array(
probeInvalidate -> getReleaseType(M_FLUSH, meta),
probeDowngrade -> getReleaseType(M_PRODUCE, meta),
probeCopy -> getReleaseType(M_CLEAN, meta)))
def clientMetadataOnHit(cmd: UInt, meta: ClientMetadata) =
ClientMetadata(Mux(isWrite(cmd), clientExclusiveDirty, meta.state))(meta.p)
def clientMetadataOnCacheControl(cmd: UInt, meta: ClientMetadata) =
ClientMetadata(
MuxLookup(cmd, meta.state, Array(
M_FLUSH -> clientInvalid,
M_PRODUCE -> Mux(clientStatesWithWritePermission.contains(meta.state),
clientShared, meta.state))))(meta.p)
def clientMetadataOnGrant(incoming: HasGrantType, cmd: UInt, meta: ClientMetadata) =
ClientMetadata(
Mux(incoming.isBuiltInType(), clientInvalid,
MuxLookup(incoming.g_type, clientInvalid, Array(
grantShared -> clientShared,
grantExclusive -> clientExclusiveDirty,
grantExclusiveAck -> clientExclusiveDirty))))(meta.p)
def clientMetadataOnProbe(incoming: HasProbeType, meta: ClientMetadata) =
ClientMetadata(
MuxLookup(incoming.p_type, meta.state, Array(
probeInvalidate -> clientInvalid,
probeDowngrade -> clientShared,
probeCopy -> meta.state)))(meta.p)
// Manager states and functions:
val nManagerStates = 0 // TODO: We could add a Shared state to avoid probing
// only a single sharer (also would need
// notification msg to track clean drops)
// Also could avoid probes on outer WBs.
def requiresProbes(a: HasAcquireType, meta: ManagerMetadata) =
Mux(dir.none(meta.sharers), Bool(false),
Mux(dir.one(meta.sharers), Bool(true), //TODO: for now we assume it's Exclusive
Mux(a.isBuiltInType(), a.hasData(), a.a_type =/= acquireShared)))
def requiresProbes(cmd: UInt, meta: ManagerMetadata) = !dir.none(meta.sharers)
def getProbeType(cmd: UInt, meta: ManagerMetadata): UInt =
MuxLookup(cmd, probeCopy, Array(
M_FLUSH -> probeInvalidate,
M_PRODUCE -> probeDowngrade))
def getProbeType(a: HasAcquireType, meta: ManagerMetadata): UInt =
Mux(a.isBuiltInType(),
MuxLookup(a.a_type, probeCopy, Array(
Acquire.getBlockType -> probeCopy,
Acquire.putBlockType -> probeInvalidate,
Acquire.getType -> probeCopy,
Acquire.putType -> probeInvalidate,
Acquire.getPrefetchType -> probeCopy,
Acquire.putPrefetchType -> probeInvalidate,
Acquire.putAtomicType -> probeInvalidate)),
MuxLookup(a.a_type, probeCopy, Array(
acquireShared -> probeDowngrade,
acquireExclusive -> probeInvalidate)))
def getGrantType(a: HasAcquireType, meta: ManagerMetadata): UInt =
Mux(a.isBuiltInType(), Acquire.getBuiltInGrantType(a.a_type),
Mux(a.a_type === acquireShared,
Mux(!dir.none(meta.sharers), grantShared, grantExclusive),
grantExclusive))
def getExclusiveGrantType(): UInt = grantExclusive
def managerMetadataOnRelease(incoming: HasReleaseType, src: UInt, meta: ManagerMetadata) = {
val popped = ManagerMetadata(sharers=dir.pop(meta.sharers, src))(meta.p)
MuxBundle(meta, Array(
incoming.is(releaseInvalidateData) -> popped,
incoming.is(releaseInvalidateAck) -> popped))
}
}
/** A protocol with four Client states.
* Data is marked as dirty when written.
* Multiple clients may share read permissions on a block at the same time.
*/
class MESICoherence(dir: DirectoryRepresentation) extends CoherencePolicy(dir) {
// Message types
val nAcquireTypes = 2
val nProbeTypes = 3
val nReleaseTypes = 6
val nGrantTypes = 3
val acquireShared :: acquireExclusive :: Nil = Enum(UInt(), nAcquireTypes)
val probeInvalidate :: probeDowngrade :: probeCopy :: Nil = Enum(UInt(), nProbeTypes)
val releaseInvalidateData :: releaseDowngradeData :: releaseCopyData :: releaseInvalidateAck :: releaseDowngradeAck :: releaseCopyAck :: Nil = Enum(UInt(), nReleaseTypes)
val grantShared :: grantExclusive :: grantExclusiveAck :: Nil = Enum(UInt(), nGrantTypes)
def releaseTypesWithData = Vec(releaseInvalidateData, releaseDowngradeData, releaseCopyData)
def grantTypesWithData = Vec(grantShared, grantExclusive)
// Client states and functions
val nClientStates = 4
val clientInvalid :: clientShared :: clientExclusiveClean :: clientExclusiveDirty :: Nil = Enum(UInt(), nClientStates)
def clientStatesWithReadPermission = Vec(clientShared, clientExclusiveClean, clientExclusiveDirty)
def clientStatesWithWritePermission = Vec(clientExclusiveClean, clientExclusiveDirty)
def clientStatesWithDirtyData = Vec(clientExclusiveDirty)
def isValid(meta: ClientMetadata): Bool = meta.state =/= clientInvalid
def getAcquireType(cmd: UInt, meta: ClientMetadata): UInt =
Mux(isWriteIntent(cmd), acquireExclusive, acquireShared)
def getReleaseType(cmd: UInt, meta: ClientMetadata): UInt = {
val dirty = clientStatesWithDirtyData.contains(meta.state)
MuxLookup(cmd, releaseCopyAck, Array(
M_FLUSH -> Mux(dirty, releaseInvalidateData, releaseInvalidateAck),
M_PRODUCE -> Mux(dirty, releaseDowngradeData, releaseDowngradeAck),
M_CLEAN -> Mux(dirty, releaseCopyData, releaseCopyAck)))
}
def getReleaseType(incoming: HasProbeType, meta: ClientMetadata): UInt =
MuxLookup(incoming.p_type, releaseInvalidateAck, Array(
probeInvalidate -> getReleaseType(M_FLUSH, meta),
probeDowngrade -> getReleaseType(M_PRODUCE, meta),
probeCopy -> getReleaseType(M_CLEAN, meta)))
def clientMetadataOnHit(cmd: UInt, meta: ClientMetadata) =
ClientMetadata(Mux(isWrite(cmd), clientExclusiveDirty, meta.state))(meta.p)
def clientMetadataOnCacheControl(cmd: UInt, meta: ClientMetadata) =
ClientMetadata(
MuxLookup(cmd, meta.state, Array(
M_FLUSH -> clientInvalid,
M_PRODUCE -> Mux(clientStatesWithWritePermission.contains(meta.state),
clientShared, meta.state),
M_CLEAN -> Mux(meta.state === clientExclusiveDirty,
clientExclusiveClean, meta.state))))(meta.p)
def clientMetadataOnGrant(incoming: HasGrantType, cmd: UInt, meta: ClientMetadata) =
ClientMetadata(
Mux(incoming.isBuiltInType(), clientInvalid,
MuxLookup(incoming.g_type, clientInvalid, Array(
grantShared -> clientShared,
grantExclusive -> Mux(isWrite(cmd), clientExclusiveDirty, clientExclusiveClean),
grantExclusiveAck -> clientExclusiveDirty))))(meta.p)
def clientMetadataOnProbe(incoming: HasProbeType, meta: ClientMetadata) =
ClientMetadata(
MuxLookup(incoming.p_type, meta.state, Array(
probeInvalidate -> clientInvalid,
probeDowngrade -> clientShared,
probeCopy -> meta.state)))(meta.p)
// Manager states and functions:
val nManagerStates = 0 // TODO: We could add a Shared state to avoid probing
// only a single sharer (also would need
// notification msg to track clean drops)
// Also could avoid probes on outer WBs.
def requiresProbes(a: HasAcquireType, meta: ManagerMetadata) =
Mux(dir.none(meta.sharers), Bool(false),
Mux(dir.one(meta.sharers), Bool(true), //TODO: for now we assume it's Exclusive
Mux(a.isBuiltInType(), a.hasData(), a.a_type =/= acquireShared)))
def requiresProbes(cmd: UInt, meta: ManagerMetadata) = !dir.none(meta.sharers)
def getProbeType(cmd: UInt, meta: ManagerMetadata): UInt =
MuxLookup(cmd, probeCopy, Array(
M_FLUSH -> probeInvalidate,
M_PRODUCE -> probeDowngrade))
def getProbeType(a: HasAcquireType, meta: ManagerMetadata): UInt =
Mux(a.isBuiltInType(),
MuxLookup(a.a_type, probeCopy, Array(
Acquire.getBlockType -> probeCopy,
Acquire.putBlockType -> probeInvalidate,
Acquire.getType -> probeCopy,
Acquire.putType -> probeInvalidate,
Acquire.getPrefetchType -> probeCopy,
Acquire.putPrefetchType -> probeInvalidate,
Acquire.putAtomicType -> probeInvalidate)),
MuxLookup(a.a_type, probeCopy, Array(
acquireShared -> probeDowngrade,
acquireExclusive -> probeInvalidate)))
def getGrantType(a: HasAcquireType, meta: ManagerMetadata): UInt =
Mux(a.isBuiltInType(), Acquire.getBuiltInGrantType(a.a_type),
Mux(a.a_type === acquireShared,
Mux(!dir.none(meta.sharers), grantShared, grantExclusive),
grantExclusive))
def getExclusiveGrantType(): UInt = grantExclusive
def managerMetadataOnRelease(incoming: HasReleaseType, src: UInt, meta: ManagerMetadata) = {
val popped = ManagerMetadata(sharers=dir.pop(meta.sharers, src))(meta.p)
MuxBundle(meta, Array(
incoming.is(releaseInvalidateData) -> popped,
incoming.is(releaseInvalidateAck) -> popped))
}
}
class MigratoryCoherence(dir: DirectoryRepresentation) extends CoherencePolicy(dir) {
// Message types
val nAcquireTypes = 3
val nProbeTypes = 4
val nReleaseTypes = 10
val nGrantTypes = 4
val acquireShared :: acquireExclusive :: acquireInvalidateOthers :: Nil = Enum(UInt(), nAcquireTypes)
val probeInvalidate :: probeDowngrade :: probeCopy :: probeInvalidateOthers :: Nil = Enum(UInt(), nProbeTypes)
val releaseInvalidateData :: releaseDowngradeData :: releaseCopyData :: releaseInvalidateAck :: releaseDowngradeAck :: releaseCopyAck :: releaseDowngradeDataMigratory :: releaseDowngradeAckHasCopy :: releaseInvalidateDataMigratory :: releaseInvalidateAckMigratory :: Nil = Enum(UInt(), nReleaseTypes)
val grantShared :: grantExclusive :: grantExclusiveAck :: grantReadMigratory :: Nil = Enum(UInt(), nGrantTypes)
def releaseTypesWithData = Vec(releaseInvalidateData, releaseDowngradeData, releaseCopyData, releaseInvalidateDataMigratory, releaseDowngradeDataMigratory)
def grantTypesWithData = Vec(grantShared, grantExclusive, grantReadMigratory)
// Client states and functions
val nClientStates = 7
val clientInvalid :: clientShared :: clientExclusiveClean :: clientExclusiveDirty :: clientSharedByTwo :: clientMigratoryClean :: clientMigratoryDirty :: Nil = Enum(UInt(), nClientStates)
def clientStatesWithReadPermission = Vec(clientShared, clientExclusiveClean, clientExclusiveDirty, clientSharedByTwo, clientMigratoryClean, clientMigratoryDirty)
def clientStatesWithWritePermission = Vec(clientExclusiveClean, clientExclusiveDirty, clientMigratoryClean, clientMigratoryDirty)
def clientStatesWithDirtyData = Vec(clientExclusiveDirty, clientMigratoryDirty)
def isValid (meta: ClientMetadata): Bool = meta.state =/= clientInvalid
def getAcquireType(cmd: UInt, meta: ClientMetadata): UInt =
Mux(isWriteIntent(cmd),
Mux(meta.state === clientInvalid, acquireExclusive, acquireInvalidateOthers),
acquireShared)
def getReleaseType(cmd: UInt, meta: ClientMetadata): UInt = {
val dirty = clientStatesWithDirtyData.contains(meta.state)
MuxLookup(cmd, releaseCopyAck, Array(
M_FLUSH -> Mux(dirty, releaseInvalidateData, releaseInvalidateAck),
M_PRODUCE -> Mux(dirty, releaseDowngradeData, releaseDowngradeAck),
M_CLEAN -> Mux(dirty, releaseCopyData, releaseCopyAck)))
}
def getReleaseType(incoming: HasProbeType, meta: ClientMetadata): UInt = {
val dirty = clientStatesWithDirtyData.contains(meta.state)
val with_data = MuxLookup(incoming.p_type, releaseInvalidateData, Array(
probeInvalidate -> Mux(Vec(clientExclusiveDirty, clientMigratoryDirty).contains(meta.state),
releaseInvalidateDataMigratory, releaseInvalidateData),
probeDowngrade -> Mux(meta.state === clientMigratoryDirty,
releaseDowngradeDataMigratory, releaseDowngradeData),
probeCopy -> releaseCopyData))
val without_data = MuxLookup(incoming.p_type, releaseInvalidateAck, Array(
probeInvalidate -> Mux(clientExclusiveClean === meta.state,
releaseInvalidateAckMigratory, releaseInvalidateAck),
probeInvalidateOthers -> Mux(clientSharedByTwo === meta.state,
releaseInvalidateAckMigratory, releaseInvalidateAck),
probeDowngrade -> Mux(meta.state =/= clientInvalid,
releaseDowngradeAckHasCopy, releaseDowngradeAck),
probeCopy -> releaseCopyAck))
Mux(dirty, with_data, without_data)
}
def clientMetadataOnHit(cmd: UInt, meta: ClientMetadata) =
ClientMetadata(
Mux(isWrite(cmd), MuxLookup(meta.state, clientExclusiveDirty, Array(
clientExclusiveClean -> clientExclusiveDirty,
clientMigratoryClean -> clientMigratoryDirty)),
meta.state))(meta.p)
def clientMetadataOnCacheControl(cmd: UInt, meta: ClientMetadata) =
ClientMetadata(
MuxLookup(cmd, meta.state, Array(
M_FLUSH -> clientInvalid,
M_PRODUCE -> Mux(clientStatesWithWritePermission.contains(meta.state),
clientShared, meta.state),
M_CLEAN -> MuxLookup(meta.state, meta.state, Array(
clientExclusiveDirty -> clientExclusiveClean,
clientMigratoryDirty -> clientMigratoryClean)))))(meta.p)
def clientMetadataOnGrant(incoming: HasGrantType, cmd: UInt, meta: ClientMetadata) =
ClientMetadata(
Mux(incoming.isBuiltInType(), clientInvalid,
MuxLookup(incoming.g_type, clientInvalid, Array(
grantShared -> clientShared,
grantExclusive -> Mux(isWrite(cmd), clientExclusiveDirty, clientExclusiveClean),
grantExclusiveAck -> clientExclusiveDirty,
grantReadMigratory -> Mux(isWrite(cmd),
clientMigratoryDirty, clientMigratoryClean)))))(meta.p)
def clientMetadataOnProbe(incoming: HasProbeType, meta: ClientMetadata) =
ClientMetadata(
MuxLookup(incoming.p_type, meta.state, Array(
probeInvalidate -> clientInvalid,
probeInvalidateOthers -> clientInvalid,
probeCopy -> meta.state,
probeDowngrade -> MuxLookup(meta.state, clientShared, Array(
clientExclusiveClean -> clientSharedByTwo,
clientExclusiveDirty -> clientSharedByTwo,
clientSharedByTwo -> clientShared,
clientMigratoryClean -> clientSharedByTwo,
clientMigratoryDirty -> clientInvalid)))))(meta.p)
// Manager states and functions:
val nManagerStates = 0 // TODO: we could add some states to reduce the number of message types
def requiresProbes(a: HasAcquireType, meta: ManagerMetadata) =
Mux(dir.none(meta.sharers), Bool(false),
Mux(dir.one(meta.sharers), Bool(true), //TODO: for now we assume it's Exclusive
Mux(a.isBuiltInType(), a.hasData(), a.a_type =/= acquireShared)))
def requiresProbes(cmd: UInt, meta: ManagerMetadata) = !dir.none(meta.sharers)
def getProbeType(cmd: UInt, meta: ManagerMetadata): UInt =
MuxLookup(cmd, probeCopy, Array(
M_FLUSH -> probeInvalidate,
M_PRODUCE -> probeDowngrade))
def getProbeType(a: HasAcquireType, meta: ManagerMetadata): UInt =
Mux(a.isBuiltInType(),
MuxLookup(a.a_type, probeCopy, Array(
Acquire.getBlockType -> probeCopy,
Acquire.putBlockType -> probeInvalidate,
Acquire.getType -> probeCopy,
Acquire.putType -> probeInvalidate,
Acquire.getPrefetchType -> probeCopy,
Acquire.putPrefetchType -> probeInvalidate,
Acquire.putAtomicType -> probeInvalidate)),
MuxLookup(a.a_type, probeCopy, Array(
acquireShared -> probeDowngrade,
acquireExclusive -> probeInvalidate,
acquireInvalidateOthers -> probeInvalidateOthers)))
def getGrantType(a: HasAcquireType, meta: ManagerMetadata): UInt =
Mux(a.isBuiltInType(), Acquire.getBuiltInGrantType(a.a_type),
MuxLookup(a.a_type, grantShared, Array(
acquireShared -> Mux(!dir.none(meta.sharers), grantShared, grantExclusive),
acquireExclusive -> grantExclusive,
acquireInvalidateOthers -> grantExclusiveAck))) //TODO: add this to MESI for broadcast?
def getExclusiveGrantType(): UInt = grantExclusive
def managerMetadataOnRelease(incoming: HasReleaseType, src: UInt, meta: ManagerMetadata) = {
val popped = ManagerMetadata(sharers=dir.pop(meta.sharers, src))(meta.p)
MuxBundle(meta, Array(
incoming.is(releaseInvalidateData) -> popped,
incoming.is(releaseInvalidateAck) -> popped,
incoming.is(releaseInvalidateDataMigratory) -> popped,
incoming.is(releaseInvalidateAckMigratory) -> popped))
}
}