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L2 Writeback bugfix

This commit is contained in:
Henry Cook 2015-03-10 01:15:03 -07:00
parent a1f04386f7
commit 17072a0041
3 changed files with 42 additions and 24 deletions

View File

@ -566,17 +566,16 @@ class L2AcquireTracker(trackerId: Int, bankId: Int) extends L2XactTracker {
val is_hit = xact_tag_match && xact_meta.coh.outer.isHit(xact.op_code()) val is_hit = xact_tag_match && xact_meta.coh.outer.isHit(xact.op_code())
val do_allocate = xact.allocate() val do_allocate = xact.allocate()
val needs_writeback = !xact_tag_match && do_allocate && val needs_writeback = !xact_tag_match && do_allocate &&
xact_meta.coh.outer.requiresVoluntaryWriteback() (xact_meta.coh.outer.requiresVoluntaryWriteback() ||
val needs_probes = xact_meta.coh.inner.requiresProbes(xact) xact_meta.coh.inner.requiresProbesOnVoluntaryWriteback())
val pending_coh_on_hit = HierarchicalMetadata( val pending_coh_on_hit = HierarchicalMetadata(
io.meta.resp.bits.meta.coh.inner, io.meta.resp.bits.meta.coh.inner,
io.meta.resp.bits.meta.coh.outer.onHit(xact.op_code())) io.meta.resp.bits.meta.coh.outer.onHit(xact.op_code()))
val pending_coh_on_irel = HierarchicalMetadata( val pending_icoh_on_irel = pending_coh.inner.onRelease(
pending_coh.inner.onRelease(
incoming = io.irel(), incoming = io.irel(),
src = io.inner.release.bits.header.src), src = io.inner.release.bits.header.src)
pending_coh.outer.onHit(M_XWR)) // WB is a write val pending_ocoh_on_irel = pending_coh.outer.onHit(M_XWR) // WB is a write
val pending_coh_on_ognt = HierarchicalMetadata( val pending_coh_on_ognt = HierarchicalMetadata(
ManagerMetadata.onReset, ManagerMetadata.onReset,
pending_coh.outer.onGrant(io.ognt(), xact.op_code())) pending_coh.outer.onGrant(io.ognt(), xact.op_code()))
@ -768,7 +767,8 @@ class L2AcquireTracker(trackerId: Int, bankId: Int) extends L2XactTracker {
val _tag_match = io.meta.resp.bits.tag_match val _tag_match = io.meta.resp.bits.tag_match
val _is_hit = _tag_match && _coh.outer.isHit(xact.op_code()) val _is_hit = _tag_match && _coh.outer.isHit(xact.op_code())
val _needs_writeback = !_tag_match && do_allocate && val _needs_writeback = !_tag_match && do_allocate &&
_coh.outer.requiresVoluntaryWriteback() (_coh.outer.requiresVoluntaryWriteback() ||
_coh.inner.requiresProbesOnVoluntaryWriteback())
val _needs_probes = _tag_match && _coh.inner.requiresProbes(xact) val _needs_probes = _tag_match && _coh.inner.requiresProbes(xact)
when(_is_hit) { pending_coh := pending_coh_on_hit } when(_is_hit) { pending_coh := pending_coh_on_hit }
when(_needs_probes) { when(_needs_probes) {
@ -796,12 +796,13 @@ class L2AcquireTracker(trackerId: Int, bankId: Int) extends L2XactTracker {
// Handle releases, which may have data being written back // Handle releases, which may have data being written back
io.inner.release.ready := Bool(true) io.inner.release.ready := Bool(true)
when(io.inner.release.valid) { when(io.inner.release.valid) {
pending_coh := pending_coh_on_irel pending_coh.inner := pending_icoh_on_irel
// Handle released dirty data // Handle released dirty data
//TODO: make sure cacq data is actually present before accpeting //TODO: make sure cacq data is actually present before accpeting
// release data to merge! // release data to merge!
when(io.irel().hasData()) { when(io.irel().hasData()) {
irel_had_data := Bool(true) irel_had_data := Bool(true)
pending_coh.outer := pending_ocoh_on_irel
mergeDataInner(data_buffer, io.irel()) mergeDataInner(data_buffer, io.irel())
} }
// We don't decrement release_count until we've received all the data beats. // We don't decrement release_count until we've received all the data beats.
@ -933,6 +934,7 @@ class L2WritebackUnit(trackerId: Int, bankId: Int) extends L2XactTracker {
val pending_icoh_on_irel = xact_coh.inner.onRelease( val pending_icoh_on_irel = xact_coh.inner.onRelease(
incoming = io.irel(), incoming = io.irel(),
src = io.inner.release.bits.header.src) src = io.inner.release.bits.header.src)
val pending_ocoh_on_irel = xact_coh.outer.onHit(M_XWR) // WB is a write
io.has_acquire_conflict := Bool(false) io.has_acquire_conflict := Bool(false)
io.has_acquire_match := Bool(false) io.has_acquire_match := Bool(false)
@ -1008,6 +1010,7 @@ class L2WritebackUnit(trackerId: Int, bankId: Int) extends L2XactTracker {
// Handle released dirty data // Handle released dirty data
when(io.irel().hasData()) { when(io.irel().hasData()) {
irel_had_data := Bool(true) irel_had_data := Bool(true)
xact_coh.outer := pending_ocoh_on_irel
data_buffer(io.irel().addr_beat) := io.irel().data data_buffer(io.irel().addr_beat) := io.irel().data
} }
// We don't decrement release_count until we've received all the data beats. // We don't decrement release_count until we've received all the data beats.
@ -1016,7 +1019,11 @@ class L2WritebackUnit(trackerId: Int, bankId: Int) extends L2XactTracker {
} }
} }
when(release_count === UInt(0)) { when(release_count === UInt(0)) {
state := Mux(irel_had_data, s_outer_release, s_data_read) state := Mux(irel_had_data, // If someone released a dirty block
s_outer_release, // write that block back, otherwise
Mux(xact_coh.outer.requiresVoluntaryWriteback(),
s_data_read, // write extant dirty data back, or just
s_wb_resp)) // drop a clean block after collecting acks
} }
} }
is(s_data_read) { is(s_data_read) {

View File

@ -383,6 +383,7 @@ class MSICoherence(dir: DirectoryRepresentation) extends CoherencePolicy(dir) {
val nManagerStates = 0 // TODO: We could add a Shared state to avoid probing val nManagerStates = 0 // TODO: We could add a Shared state to avoid probing
// only a single sharer (also would need // only a single sharer (also would need
// notification msg to track clean drops) // notification msg to track clean drops)
// Also could avoid probes on outer WBs.
def requiresProbes(a: Acquire, meta: ManagerMetadata) = def requiresProbes(a: Acquire, meta: ManagerMetadata) =
Mux(dir.none(meta.sharers), Bool(false), Mux(dir.none(meta.sharers), Bool(false),
@ -501,6 +502,7 @@ class MESICoherence(dir: DirectoryRepresentation) extends CoherencePolicy(dir) {
val nManagerStates = 0 // TODO: We could add a Shared state to avoid probing val nManagerStates = 0 // TODO: We could add a Shared state to avoid probing
// only a single sharer (also would need // only a single sharer (also would need
// notification msg to track clean drops) // notification msg to track clean drops)
// Also could avoid probes on outer WBs.
def requiresProbes(a: Acquire, meta: ManagerMetadata) = def requiresProbes(a: Acquire, meta: ManagerMetadata) =
Mux(dir.none(meta.sharers), Bool(false), Mux(dir.none(meta.sharers), Bool(false),

View File

@ -212,6 +212,7 @@ class MemIOTileLinkIOConverter(qDepth: Int) extends Module {
val mem = new MemIO val mem = new MemIO
} }
val mifTagBits = params(MIFTagBits) val mifTagBits = params(MIFTagBits)
val mifAddrBits = params(MIFAddrBits)
val mifDataBits = params(MIFDataBits) val mifDataBits = params(MIFDataBits)
val mifDataBeats = params(MIFDataBeats) val mifDataBeats = params(MIFDataBeats)
val tlDataBits = params(TLDataBits) val tlDataBits = params(TLDataBits)
@ -235,8 +236,8 @@ class MemIOTileLinkIOConverter(qDepth: Int) extends Module {
// Decompose outgoing TL Acquires into MemIO cmd and data // Decompose outgoing TL Acquires into MemIO cmd and data
val active_out = Reg(init=Bool(false)) val active_out = Reg(init=Bool(false))
val cmd_sent_out = Reg(init=Bool(false)) val cmd_sent_out = Reg(init=Bool(false))
val tag_out = Reg(Bits()) val tag_out = Reg(UInt(width = mifTagBits))
val addr_out = Reg(Bits()) val addr_out = Reg(UInt(width = mifAddrBits))
val has_data = Reg(init=Bool(false)) val has_data = Reg(init=Bool(false))
val data_from_rel = Reg(init=Bool(false)) val data_from_rel = Reg(init=Bool(false))
val (tl_cnt_out, tl_wrap_out) = val (tl_cnt_out, tl_wrap_out) =
@ -343,26 +344,34 @@ class MemIOTileLinkIOConverter(qDepth: Int) extends Module {
active_out := !io.mem.req_cmd.ready || io.mem.req_data.valid active_out := !io.mem.req_cmd.ready || io.mem.req_data.valid
io.mem.req_cmd.valid := Bool(true) io.mem.req_cmd.valid := Bool(true)
cmd_sent_out := io.mem.req_cmd.ready cmd_sent_out := io.mem.req_cmd.ready
tag_out := io.mem.req_cmd.bits.tag
addr_out := io.mem.req_data.bits.data
has_data := io.mem.req_cmd.bits.rw
tl_done_out := tl_wrap_out tl_done_out := tl_wrap_out
when(io.tl.release.valid) { when(io.tl.release.valid) {
data_from_rel := Bool(true) data_from_rel := Bool(true)
make_grant_ack := Bool(true) make_grant_ack := Bool(true)
io.mem.req_cmd.bits.rw := rel_has_data
io.mem.req_cmd.bits.tag := Cat(io.tl.release.bits.payload.client_xact_id,
io.tl.release.bits.payload.isVoluntary())
io.mem.req_cmd.bits.addr := io.tl.release.bits.payload.addr_block
io.mem.req_data.bits.data := io.tl.release.bits.payload.data io.mem.req_data.bits.data := io.tl.release.bits.payload.data
val tag = Cat(io.tl.release.bits.payload.client_xact_id,
io.tl.release.bits.payload.isVoluntary())
val addr = io.tl.release.bits.payload.addr_block
io.mem.req_cmd.bits.tag := tag
io.mem.req_cmd.bits.addr := addr
io.mem.req_cmd.bits.rw := rel_has_data
tag_out := tag
addr_out := addr
has_data := rel_has_data
} .elsewhen(io.tl.acquire.valid) { } .elsewhen(io.tl.acquire.valid) {
data_from_rel := Bool(false) data_from_rel := Bool(false)
make_grant_ack := acq_has_data make_grant_ack := acq_has_data
io.mem.req_cmd.bits.rw := acq_has_data
io.mem.req_cmd.bits.tag := Cat(io.tl.acquire.bits.payload.client_xact_id,
io.tl.acquire.bits.payload.isBuiltInType())
io.mem.req_cmd.bits.addr := io.tl.acquire.bits.payload.addr_block
io.mem.req_data.bits.data := io.tl.acquire.bits.payload.data io.mem.req_data.bits.data := io.tl.acquire.bits.payload.data
io.mem.req_cmd.bits.rw := acq_has_data
val tag = Cat(io.tl.acquire.bits.payload.client_xact_id,
io.tl.acquire.bits.payload.isBuiltInType())
val addr = io.tl.acquire.bits.payload.addr_block
io.mem.req_cmd.bits.tag := tag
io.mem.req_cmd.bits.addr := addr
io.mem.req_cmd.bits.rw := acq_has_data
tag_out := tag
addr_out := addr
has_data := acq_has_data
} }
} }
} }
@ -380,7 +389,7 @@ class MemIOTileLinkIOConverter(qDepth: Int) extends Module {
} }
when(tl_wrap_out) { tl_done_out := Bool(true) } when(tl_wrap_out) { tl_done_out := Bool(true) }
when(tl_done_out && make_grant_ack) { when(tl_done_out && make_grant_ack) {
gnt_arb.io.in(1).valid := Bool(true) gnt_arb.io.in(1).valid := Bool(true) // TODO: grants for voluntary acks?
when(gnt_arb.io.in(1).ready) { make_grant_ack := Bool(false) } when(gnt_arb.io.in(1).ready) { make_grant_ack := Bool(false) }
} }
when(cmd_sent_out && (!has_data || tl_done_out) && !make_grant_ack) { when(cmd_sent_out && (!has_data || tl_done_out) && !make_grant_ack) {