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rocket-chip/uncore/src/main/scala/agents/Broadcast.scala
2016-07-05 12:08:22 -07:00

203 lines
7.0 KiB
Scala

// See LICENSE for license details.
package uncore.agents
import Chisel._
import uncore.coherence._
import uncore.tilelink._
import uncore.constants._
import cde.Parameters
class L2BroadcastHub(implicit p: Parameters) extends HierarchicalCoherenceAgent()(p) {
// Create TSHRs for outstanding transactions
val irelTrackerList =
(0 until nReleaseTransactors).map(id =>
Module(new BufferedBroadcastVoluntaryReleaseTracker(id)))
val iacqTrackerList =
(nReleaseTransactors until nTransactors).map(id =>
Module(new BufferedBroadcastAcquireTracker(id)))
val trackerList = irelTrackerList ++ iacqTrackerList
// Propagate incoherence flags
trackerList.map(_.io.incoherent) foreach { _ := io.incoherent }
// Create an arbiter for the one memory port
val outerList = trackerList.map(_.io.outer)
val outer_arb = Module(new ClientTileLinkIOArbiter(outerList.size)
(p.alterPartial({ case TLId => p(OuterTLId) })))
outer_arb.io.in <> outerList
io.outer <> outer_arb.io.out
// Handle acquire transaction initiation
val irel_vs_iacq_conflict =
io.inner.acquire.valid &&
io.inner.release.valid &&
io.irel().conflicts(io.iacq())
doInputRoutingWithAllocation(
in = io.inner.acquire,
outs = trackerList.map(_.io.inner.acquire),
allocs = trackerList.map(_.io.alloc.iacq),
allocOverride = Some(!irel_vs_iacq_conflict))
// Handle releases, which might be voluntary and might have data
doInputRoutingWithAllocation(
in = io.inner.release,
outs = trackerList.map(_.io.inner.release),
allocs = trackerList.map(_.io.alloc.irel))
// Wire probe requests and grant reply to clients, finish acks from clients
doOutputArbitration(io.inner.probe, trackerList.map(_.io.inner.probe))
doOutputArbitration(io.inner.grant, trackerList.map(_.io.inner.grant))
doInputRouting(io.inner.finish, trackerList.map(_.io.inner.finish))
}
class BroadcastXactTracker(implicit p: Parameters) extends XactTracker()(p) {
val io = new HierarchicalXactTrackerIO
pinAllReadyValidLow(io)
}
trait BroadcastsToAllClients extends HasCoherenceAgentParameters {
val coh = HierarchicalMetadata.onReset
val inner_coh = coh.inner
val outer_coh = coh.outer
def full_representation = ~UInt(0, width = innerNCachingClients)
}
abstract class BroadcastVoluntaryReleaseTracker(trackerId: Int)(implicit p: Parameters)
extends VoluntaryReleaseTracker(trackerId)(p)
with EmitsVoluntaryReleases
with BroadcastsToAllClients {
val io = new HierarchicalXactTrackerIO
pinAllReadyValidLow(io)
// Checks for illegal behavior
assert(!(state === s_idle && io.inner.release.fire() && io.alloc.irel.should && !io.irel().isVoluntary()),
"VoluntaryReleaseTracker accepted Release that wasn't voluntary!")
}
abstract class BroadcastAcquireTracker(trackerId: Int)(implicit p: Parameters)
extends AcquireTracker(trackerId)(p)
with EmitsVoluntaryReleases
with BroadcastsToAllClients {
val io = new HierarchicalXactTrackerIO
pinAllReadyValidLow(io)
val alwaysWriteFullBeat = false
val nSecondaryMisses = 1
def iacq_can_merge = Bool(false)
// Checks for illegal behavior
// TODO: this could be allowed, but is a useful check against allocation gone wild
assert(!(state === s_idle && io.inner.acquire.fire() && io.alloc.iacq.should &&
io.iacq().hasMultibeatData() && !io.iacq().first()),
"AcquireTracker initialized with a tail data beat.")
assert(!(state =/= s_idle && pending_ignt && xact_iacq.isPrefetch()),
"Broadcast Hub does not support Prefetches.")
assert(!(state =/= s_idle && pending_ignt && xact_iacq.isAtomic()),
"Broadcast Hub does not support PutAtomics.")
}
class BufferedBroadcastVoluntaryReleaseTracker(trackerId: Int)(implicit p: Parameters)
extends BroadcastVoluntaryReleaseTracker(trackerId)(p)
with HasDataBuffer {
// Tell the parent if any incoming messages conflict with the ongoing transaction
routeInParent()
io.alloc.iacq.can := Bool(false)
// Start transaction by accepting inner release
innerRelease(block_vol_ignt = pending_orel || vol_ognt_counter.pending)
// A release beat can be accepted if we are idle, if its a mergeable transaction, or if its a tail beat
io.inner.release.ready := state === s_idle || irel_can_merge || irel_same_xact
when(io.inner.release.fire()) { data_buffer(io.irel().addr_beat) := io.irel().data }
// Dispatch outer release
outerRelease(
coh = outer_coh.onHit(M_XWR),
data = data_buffer(vol_ognt_counter.up.idx),
add_pending_send_bit = irel_is_allocating)
quiesce() {}
}
class BufferedBroadcastAcquireTracker(trackerId: Int)(implicit p: Parameters)
extends BroadcastAcquireTracker(trackerId)(p)
with HasByteWriteMaskBuffer {
// Setup IOs used for routing in the parent
routeInParent()
io.alloc.irel.can := Bool(false)
// First, take care of accpeting new acquires or secondary misses
// Handling of primary and secondary misses' data and write mask merging
innerAcquire(
can_alloc = Bool(false),
next = s_inner_probe)
io.inner.acquire.ready := state === s_idle || iacq_can_merge || iacq_same_xact_multibeat
// Track which clients yet need to be probed and make Probe message
// If a writeback occurs, we can forward its data via the buffer,
// and skip having to go outwards
val skip_outer_acquire = pending_ignt_data.andR
innerProbe(
inner_coh.makeProbe(curr_probe_dst, xact_iacq, xact_addr_block),
Mux(!skip_outer_acquire, s_outer_acquire, s_busy))
// Handle incoming releases from clients, which may reduce sharer counts
// and/or write back dirty data, and may be unexpected voluntary releases
def irel_can_merge = io.irel().conflicts(xact_addr_block) &&
io.irel().isVoluntary() &&
!Vec(s_idle, s_meta_write).contains(state) &&
!all_pending_done &&
!io.outer.grant.fire() &&
!io.inner.grant.fire() &&
!vol_ignt_counter.pending
innerRelease(block_vol_ignt = vol_ognt_counter.pending)
//TODO: accept vol irels when state === s_idle, operate like the VolRelTracker
io.inner.release.ready := irel_can_merge || irel_same_xact
mergeDataInner(io.inner.release)
// If there was a writeback, forward it outwards
outerRelease(
coh = outer_coh.onHit(M_XWR),
data = data_buffer(vol_ognt_counter.up.idx))
// Send outer request for miss
outerAcquire(
caching = !xact_iacq.isBuiltInType(),
coh = outer_coh,
data = data_buffer(ognt_counter.up.idx),
wmask = wmask_buffer(ognt_counter.up.idx),
next = s_busy)
// Handle the response from outer memory
mergeDataOuter(io.outer.grant)
// Acknowledge or respond with data
innerGrant(
data = data_buffer(ignt_data_idx),
external_pending = pending_orel || ognt_counter.pending || vol_ognt_counter.pending)
when(iacq_is_allocating) {
initializeProbes()
}
initDataInner(io.inner.acquire, iacq_is_allocating || iacq_is_merging)
// Wait for everything to quiesce
quiesce() { clearWmaskBuffer() }
}