511 lines
24 KiB
Scala
511 lines
24 KiB
Scala
// See LICENSE.SiFive for license details.
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package rocket
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import Chisel._
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import Chisel.ImplicitConversions._
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import diplomacy._
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import uncore.constants._
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import uncore.tilelink2._
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import uncore.util._
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import util._
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import TLMessages._
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import config._
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class DCacheDataReq(implicit p: Parameters) extends L1HellaCacheBundle()(p) {
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val addr = Bits(width = untagBits)
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val write = Bool()
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val wdata = Bits(width = rowBits)
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val wmask = Bits(width = rowBytes)
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val way_en = Bits(width = nWays)
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}
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class DCacheDataArray(implicit p: Parameters) extends L1HellaCacheModule()(p) {
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val io = new Bundle {
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val req = Valid(new DCacheDataReq).flip
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val resp = Vec(nWays, Bits(OUTPUT, rowBits))
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}
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val addr = io.req.bits.addr >> rowOffBits
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for (w <- 0 until nWays) {
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val array = SeqMem(nSets*refillCycles, Vec(rowBytes, Bits(width=8)))
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val valid = io.req.valid && (Bool(nWays == 1) || io.req.bits.way_en(w))
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when (valid && io.req.bits.write) {
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val data = Vec.tabulate(rowBytes)(i => io.req.bits.wdata(8*(i+1)-1, 8*i))
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array.write(addr, data, io.req.bits.wmask.toBools)
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}
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io.resp(w) := array.read(addr, valid && !io.req.bits.write).asUInt
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}
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}
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class DCache(cfg: DCacheConfig, val scratch: () => Option[AddressSet])(implicit p: Parameters) extends HellaCache(cfg)(p) {
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override lazy val module = new DCacheModule(this)
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}
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class DCacheModule(outer: DCache)(implicit p: Parameters) extends HellaCacheModule(outer)(p) {
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val maxUncachedInFlight = cfg.nMMIOs
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require(rowBits == encRowBits) // no ECC
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val grantackq = Module(new Queue(tl_out.e.bits,1)) // TODO don't need this in scratchpad mode
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// tags
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val replacer = p(Replacer)()
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def onReset = L1Metadata(UInt(0), ClientMetadata.onReset)
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val metaReadArb = Module(new Arbiter(new MetaReadReq, 3))
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val metaWriteArb = Module(new Arbiter(new L1MetaWriteReq, 3))
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// data
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val data = Module(new DCacheDataArray)
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val dataArb = Module(new Arbiter(new DCacheDataReq, 4))
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data.io.req <> dataArb.io.out
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dataArb.io.out.ready := true
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val s1_valid = Reg(next=io.cpu.req.fire(), init=Bool(false))
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val s1_probe = Reg(next=tl_out.b.fire(), init=Bool(false))
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val probe_bits = RegEnable(tl_out.b.bits, tl_out.b.fire()) // TODO has data now :(
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val s1_nack = Wire(init=Bool(false))
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val s1_valid_masked = s1_valid && !io.cpu.s1_kill && !io.cpu.xcpt.asUInt.orR
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val s1_valid_not_nacked = s1_valid_masked && !s1_nack
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val s1_req = Reg(io.cpu.req.bits)
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when (metaReadArb.io.out.valid) {
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s1_req := io.cpu.req.bits
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s1_req.addr := Cat(io.cpu.req.bits.addr >> untagBits, metaReadArb.io.out.bits.idx, io.cpu.req.bits.addr(blockOffBits-1,0))
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}
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val s1_read = isRead(s1_req.cmd)
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val s1_write = isWrite(s1_req.cmd)
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val s1_readwrite = s1_read || s1_write
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val s1_flush_valid = Reg(Bool())
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val s_ready :: s_voluntary_writeback :: s_probe_rep_dirty :: s_probe_rep_clean :: s_probe_rep_miss :: s_voluntary_write_meta :: s_probe_write_meta :: Nil = Enum(UInt(), 7)
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val cached_grant_wait = Reg(init=Bool(false))
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val release_ack_wait = Reg(init=Bool(false))
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val release_state = Reg(init=s_ready)
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val pstore1_valid = Wire(Bool())
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val pstore2_valid = Reg(Bool())
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val inWriteback = release_state.isOneOf(s_voluntary_writeback, s_probe_rep_dirty)
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val releaseWay = Wire(UInt())
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io.cpu.req.ready := (release_state === s_ready) && !cached_grant_wait && !s1_nack
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// I/O MSHRs
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val uncachedInFlight = Reg(init=Vec.fill(maxUncachedInFlight)(Bool(false)))
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val uncachedReqs = Reg(Vec(maxUncachedInFlight, new HellaCacheReq))
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// hit initiation path
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dataArb.io.in(3).valid := io.cpu.req.valid && isRead(io.cpu.req.bits.cmd)
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dataArb.io.in(3).bits.write := false
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dataArb.io.in(3).bits.addr := io.cpu.req.bits.addr
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dataArb.io.in(3).bits.way_en := ~UInt(0, nWays)
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when (!dataArb.io.in(3).ready && isRead(io.cpu.req.bits.cmd)) { io.cpu.req.ready := false }
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metaReadArb.io.in(2).valid := io.cpu.req.valid
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metaReadArb.io.in(2).bits.idx := io.cpu.req.bits.addr(idxMSB, idxLSB)
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metaReadArb.io.in(2).bits.way_en := ~UInt(0, nWays)
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when (!metaReadArb.io.in(2).ready) { io.cpu.req.ready := false }
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// address translation
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val tlb = Module(new TLB)
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io.ptw <> tlb.io.ptw
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tlb.io.req.valid := s1_valid_masked && s1_readwrite
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tlb.io.req.bits.passthrough := s1_req.phys
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tlb.io.req.bits.vpn := s1_req.addr >> pgIdxBits
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tlb.io.req.bits.instruction := false
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tlb.io.req.bits.store := s1_write
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when (!tlb.io.req.ready && !io.cpu.req.bits.phys) { io.cpu.req.ready := false }
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when (s1_valid && s1_readwrite && tlb.io.resp.miss) { s1_nack := true }
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val s1_paddr = Cat(tlb.io.resp.ppn, s1_req.addr(pgIdxBits-1,0))
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val s1_tag = Mux(s1_probe, probe_bits.address, s1_paddr)(paddrBits-1, untagBits)
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val s1_victim_way = Wire(init = replacer.way)
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val (s1_hit_way, s1_hit_state, s1_victim_meta) =
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if (usingDataScratchpad) {
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require(nWays == 1)
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metaWriteArb.io.out.ready := true
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metaReadArb.io.out.ready := !metaWriteArb.io.out.valid
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val inScratchpad = outer.scratch().map(_.contains(s1_paddr)).getOrElse(Bool(false))
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val hitState = Mux(inScratchpad, ClientMetadata.maximum, ClientMetadata.onReset)
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(inScratchpad, hitState, L1Metadata(UInt(0), ClientMetadata.onReset))
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} else {
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val meta = Module(new MetadataArray(onReset _))
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meta.io.read <> metaReadArb.io.out
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meta.io.write <> metaWriteArb.io.out
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val s1_meta = meta.io.resp
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val s1_meta_hit_way = s1_meta.map(r => r.coh.isValid() && r.tag === s1_tag).asUInt
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val s1_meta_hit_state = ClientMetadata.onReset.fromBits(
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s1_meta.map(r => Mux(r.tag === s1_tag, r.coh.asUInt, UInt(0)))
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.reduce (_|_))
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(s1_meta_hit_way, s1_meta_hit_state, s1_meta(s1_victim_way))
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}
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val s1_data_way = Mux(inWriteback, releaseWay, s1_hit_way)
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val s1_data = Mux1H(s1_data_way, data.io.resp) // retime into s2 if critical
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val s2_valid = Reg(next=s1_valid_masked, init=Bool(false))
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val s2_probe = Reg(next=s1_probe, init=Bool(false))
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val releaseInFlight = s1_probe || s2_probe || release_state =/= s_ready
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val s2_valid_masked = s2_valid && Reg(next = !s1_nack)
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val s2_req = Reg(io.cpu.req.bits)
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val s2_req_block_addr = (s2_req.addr >> idxLSB) << idxLSB
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val s2_uncached = Reg(Bool())
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when (s1_valid_not_nacked || s1_flush_valid) {
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s2_req := s1_req
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s2_req.addr := s1_paddr
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s2_uncached := !tlb.io.resp.cacheable || Bool(usingDataScratchpad)
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}
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val s2_read = isRead(s2_req.cmd)
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val s2_write = isWrite(s2_req.cmd)
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val s2_readwrite = s2_read || s2_write
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val s2_flush_valid = RegNext(s1_flush_valid)
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val s2_data = RegEnable(s1_data, s1_valid || inWriteback)
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val s2_probe_way = RegEnable(s1_hit_way, s1_probe)
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val s2_probe_state = RegEnable(s1_hit_state, s1_probe)
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val s2_hit_way = RegEnable(s1_hit_way, s1_valid_not_nacked)
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val s2_hit_state = RegEnable(s1_hit_state, s1_valid_not_nacked)
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val s2_hit_valid = s2_hit_state.isValid()
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val (s2_hit, s2_grow_param, s2_new_hit_state) = s2_hit_state.onAccess(s2_req.cmd)
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val s2_valid_hit = s2_valid_masked && s2_readwrite && s2_hit
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val s2_valid_miss = s2_valid_masked && s2_readwrite && !s2_hit && !(pstore1_valid || pstore2_valid) && !release_ack_wait
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val s2_valid_cached_miss = s2_valid_miss && !s2_uncached
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val s2_victimize = s2_valid_cached_miss || s2_flush_valid
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val s2_valid_uncached = s2_valid_miss && s2_uncached
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val s2_victim_way = Mux(s2_hit_valid && !s2_flush_valid, s2_hit_way, UIntToOH(RegEnable(s1_victim_way, s1_valid_not_nacked || s1_flush_valid)))
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val s2_victim_tag = RegEnable(s1_victim_meta.tag, s1_valid_not_nacked || s1_flush_valid)
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val s2_victim_state = Mux(s2_hit_valid && !s2_flush_valid, s2_hit_state, RegEnable(s1_victim_meta.coh, s1_valid_not_nacked || s1_flush_valid))
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val s2_victim_valid = s2_victim_state.isValid()
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val (s2_prb_ack_data, s2_report_param, probeNewCoh)= s2_probe_state.onProbe(probe_bits.param)
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val (s2_victim_dirty, s2_shrink_param, voluntaryNewCoh) = s2_victim_state.onCacheControl(M_FLUSH)
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val s2_update_meta = s2_hit_state =/= s2_new_hit_state
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io.cpu.s2_nack := s2_valid && !s2_valid_hit && !(s2_valid_uncached && tl_out.a.ready && !uncachedInFlight.asUInt.andR)
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when (s2_valid && (!s2_valid_hit || s2_update_meta)) { s1_nack := true }
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// exceptions
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val s1_storegen = new StoreGen(s1_req.typ, s1_req.addr, UInt(0), wordBytes)
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io.cpu.xcpt.ma.ld := s1_read && s1_storegen.misaligned
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io.cpu.xcpt.ma.st := s1_write && s1_storegen.misaligned
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io.cpu.xcpt.pf.ld := s1_read && tlb.io.resp.xcpt_ld
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io.cpu.xcpt.pf.st := s1_write && tlb.io.resp.xcpt_st
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// load reservations
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val s2_lr = Bool(usingAtomics) && s2_req.cmd === M_XLR
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val s2_sc = Bool(usingAtomics) && s2_req.cmd === M_XSC
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val lrscCount = Reg(init=UInt(0))
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val lrscValid = lrscCount > 0
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val lrscAddr = Reg(UInt())
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val s2_sc_fail = s2_sc && !(lrscValid && lrscAddr === (s2_req.addr >> blockOffBits))
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when (s2_valid_hit && s2_lr) {
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lrscCount := lrscCycles - 1
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lrscAddr := s2_req.addr >> blockOffBits
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}
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when (lrscValid) { lrscCount := lrscCount - 1 }
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when ((s2_valid_masked && lrscValid) || io.cpu.invalidate_lr) { lrscCount := 0 }
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// pending store buffer
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val pstore1_cmd = RegEnable(s1_req.cmd, s1_valid_not_nacked && s1_write)
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val pstore1_typ = RegEnable(s1_req.typ, s1_valid_not_nacked && s1_write)
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val pstore1_addr = RegEnable(s1_paddr, s1_valid_not_nacked && s1_write)
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val pstore1_data = RegEnable(io.cpu.s1_data, s1_valid_not_nacked && s1_write)
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val pstore1_way = RegEnable(s1_hit_way, s1_valid_not_nacked && s1_write)
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val pstore1_storegen = new StoreGen(pstore1_typ, pstore1_addr, pstore1_data, wordBytes)
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val pstore1_storegen_data = Wire(init = pstore1_storegen.data)
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val pstore1_amo = Bool(usingAtomics) && isRead(pstore1_cmd)
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val pstore_drain_structural = pstore1_valid && pstore2_valid && ((s1_valid && s1_write) || pstore1_amo)
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val pstore_drain_opportunistic = !(io.cpu.req.valid && isRead(io.cpu.req.bits.cmd))
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val pstore_drain_on_miss = releaseInFlight || io.cpu.s2_nack
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val pstore_drain =
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Bool(usingAtomics) && pstore_drain_structural ||
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(((pstore1_valid && !pstore1_amo) || pstore2_valid) && (pstore_drain_opportunistic || pstore_drain_on_miss))
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pstore1_valid := {
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val s2_store_valid = s2_valid_hit && s2_write && !s2_sc_fail
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val pstore1_held = Reg(Bool())
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assert(!s2_store_valid || !pstore1_held)
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pstore1_held := (s2_store_valid || pstore1_held) && pstore2_valid && !pstore_drain
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s2_store_valid || pstore1_held
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}
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val advance_pstore1 = pstore1_valid && (pstore2_valid === pstore_drain)
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pstore2_valid := pstore2_valid && !pstore_drain || advance_pstore1
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val pstore2_addr = RegEnable(pstore1_addr, advance_pstore1)
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val pstore2_way = RegEnable(pstore1_way, advance_pstore1)
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val pstore2_storegen_data = RegEnable(pstore1_storegen_data, advance_pstore1)
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val pstore2_storegen_mask = RegEnable(pstore1_storegen.mask, advance_pstore1)
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dataArb.io.in(0).valid := pstore_drain
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dataArb.io.in(0).bits.write := true
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dataArb.io.in(0).bits.addr := Mux(pstore2_valid, pstore2_addr, pstore1_addr)
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dataArb.io.in(0).bits.way_en := Mux(pstore2_valid, pstore2_way, pstore1_way)
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dataArb.io.in(0).bits.wdata := Fill(rowWords, Mux(pstore2_valid, pstore2_storegen_data, pstore1_storegen_data))
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val pstore_mask_shift = Mux(pstore2_valid, pstore2_addr, pstore1_addr).extract(rowOffBits-1,offsetlsb) << wordOffBits
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dataArb.io.in(0).bits.wmask := Mux(pstore2_valid, pstore2_storegen_mask, pstore1_storegen.mask) << pstore_mask_shift
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// store->load RAW hazard detection
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val s1_idx = s1_req.addr(idxMSB, wordOffBits)
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val s1_raw_hazard = s1_read &&
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((pstore1_valid && pstore1_addr(idxMSB, wordOffBits) === s1_idx && (pstore1_storegen.mask & s1_storegen.mask).orR) ||
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(pstore2_valid && pstore2_addr(idxMSB, wordOffBits) === s1_idx && (pstore2_storegen_mask & s1_storegen.mask).orR))
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when (s1_valid && s1_raw_hazard) { s1_nack := true }
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metaWriteArb.io.in(0).valid := (s2_valid_hit && s2_update_meta) || (s2_victimize && !s2_victim_dirty)
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metaWriteArb.io.in(0).bits.way_en := s2_victim_way
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metaWriteArb.io.in(0).bits.idx := s2_req.addr(idxMSB, idxLSB)
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metaWriteArb.io.in(0).bits.data.coh := Mux(s2_valid_hit, s2_new_hit_state, ClientMetadata.onReset)
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metaWriteArb.io.in(0).bits.data.tag := s2_req.addr(paddrBits-1, untagBits)
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// Prepare a TileLink request message that initiates a transaction
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val a_source = PriorityEncoder(~uncachedInFlight.asUInt)
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val acquire_address = s2_req_block_addr
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val access_address = s2_req.addr
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val a_size = s2_req.typ(MT_SZ-2, 0)
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val a_data = Fill(beatWords, pstore1_storegen.data)
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val acquire = if (edge.manager.anySupportAcquire) {
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edge.Acquire(a_source, acquire_address, lgCacheBlockBytes, s2_grow_param)._2 // Cacheability checked by tlb
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} else {
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Wire(new TLBundleA(edge.bundle))
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}
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val get = edge.Get(a_source, access_address, a_size)._2
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val put = edge.Put(a_source, access_address, a_size, a_data)._2
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val atomics = if (edge.manager.anySupportLogical) {
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MuxLookup(s2_req.cmd, Wire(new TLBundleA(edge.bundle)), Array(
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M_XA_SWAP -> edge.Logical(a_source, access_address, a_size, a_data, TLAtomics.SWAP)._2,
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M_XA_XOR -> edge.Logical(a_source, access_address, a_size, a_data, TLAtomics.XOR) ._2,
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M_XA_OR -> edge.Logical(a_source, access_address, a_size, a_data, TLAtomics.OR) ._2,
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M_XA_AND -> edge.Logical(a_source, access_address, a_size, a_data, TLAtomics.AND) ._2,
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M_XA_ADD -> edge.Arithmetic(a_source, access_address, a_size, a_data, TLAtomics.ADD)._2,
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M_XA_MIN -> edge.Arithmetic(a_source, access_address, a_size, a_data, TLAtomics.MIN)._2,
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M_XA_MAX -> edge.Arithmetic(a_source, access_address, a_size, a_data, TLAtomics.MAX)._2,
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M_XA_MINU -> edge.Arithmetic(a_source, access_address, a_size, a_data, TLAtomics.MINU)._2,
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M_XA_MAXU -> edge.Arithmetic(a_source, access_address, a_size, a_data, TLAtomics.MAXU)._2))
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} else {
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// If no managers support atomics, assert fail if processor asks for them
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assert (!(tl_out.a.valid && pstore1_amo && s2_write && s2_uncached))
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Wire(new TLBundleA(edge.bundle))
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}
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tl_out.a.valid := grantackq.io.enq.ready && ((s2_valid_cached_miss && !s2_victim_dirty) ||
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(s2_valid_uncached && !uncachedInFlight.asUInt.andR))
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tl_out.a.bits := Mux(!s2_uncached, acquire, Mux(!s2_write, get, Mux(!pstore1_amo, put, atomics)))
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// Set pending bits for outstanding TileLink transaction
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when (tl_out.a.fire()) {
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when (s2_uncached) {
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uncachedInFlight(a_source) := true
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uncachedReqs(a_source) := s2_req
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}.otherwise {
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cached_grant_wait := true
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}
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}
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// grant
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val (d_first, d_last, d_done, d_address_inc) = edge.addr_inc(tl_out.d)
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val grantIsCached = tl_out.d.bits.opcode.isOneOf(Grant, GrantData)
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val grantIsUncached = tl_out.d.bits.opcode.isOneOf(AccessAck, AccessAckData, HintAck)
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val grantIsVoluntary = tl_out.d.bits.opcode === ReleaseAck // Clears a different pending bit
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val grantIsRefill = tl_out.d.bits.opcode === GrantData // Writes the data array
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tl_out.d.ready := true
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when (tl_out.d.fire()) {
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when (grantIsCached) {
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assert(cached_grant_wait, "A GrantData was unexpected by the dcache.")
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when(d_last) { cached_grant_wait := false }
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} .elsewhen (grantIsUncached) {
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val id = tl_out.d.bits.source
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val req = uncachedReqs(id)
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assert(uncachedInFlight(id), "An AccessAck was unexpected by the dcache.") // TODO must handle Ack coming back on same cycle!
|
|
when(d_last) { uncachedInFlight(id) := false }
|
|
s2_data := tl_out.d.bits.data
|
|
s2_req.cmd := req.cmd
|
|
s2_req.typ := req.typ
|
|
s2_req.tag := req.tag
|
|
s2_req.addr := Cat(s1_paddr >> wordOffBits /* don't-care */, req.addr(wordOffBits-1, 0))
|
|
} .elsewhen (grantIsVoluntary) {
|
|
assert(release_ack_wait, "A ReleaseAck was unexpected by the dcache.") // TODO should handle Ack coming back on same cycle!
|
|
release_ack_wait := false
|
|
}
|
|
}
|
|
|
|
// data refill
|
|
val doRefillBeat = grantIsRefill && tl_out.d.valid
|
|
dataArb.io.in(1).valid := doRefillBeat
|
|
assert(dataArb.io.in(1).ready || !doRefillBeat)
|
|
dataArb.io.in(1).bits.write := true
|
|
dataArb.io.in(1).bits.addr := s2_req_block_addr | d_address_inc
|
|
dataArb.io.in(1).bits.way_en := s2_victim_way
|
|
dataArb.io.in(1).bits.wdata := tl_out.d.bits.data
|
|
dataArb.io.in(1).bits.wmask := ~UInt(0, rowBytes)
|
|
// tag updates on refill
|
|
metaWriteArb.io.in(1).valid := grantIsCached && d_done
|
|
assert(!metaWriteArb.io.in(1).valid || metaWriteArb.io.in(1).ready)
|
|
metaWriteArb.io.in(1).bits.way_en := s2_victim_way
|
|
metaWriteArb.io.in(1).bits.idx := s2_req.addr(idxMSB, idxLSB)
|
|
metaWriteArb.io.in(1).bits.data.coh := s2_hit_state.onGrant(s2_req.cmd, tl_out.d.bits.param)
|
|
metaWriteArb.io.in(1).bits.data.tag := s2_req.addr(paddrBits-1, untagBits)
|
|
// don't accept uncached grants if there's a structural hazard on s2_data...
|
|
val blockUncachedGrant = Reg(Bool())
|
|
blockUncachedGrant := dataArb.io.out.valid
|
|
when (grantIsUncached) {
|
|
tl_out.d.ready := !(blockUncachedGrant || s1_valid)
|
|
// ...but insert bubble to guarantee grant's eventual forward progress
|
|
when (tl_out.d.valid && !tl_out.d.ready) {
|
|
io.cpu.req.ready := false
|
|
dataArb.io.in(1).valid := true
|
|
dataArb.io.in(1).bits.write := false
|
|
blockUncachedGrant := !dataArb.io.in(1).ready
|
|
}
|
|
}
|
|
|
|
// Finish TileLink transaction by issuing a GrantAck
|
|
grantackq.io.enq.valid := d_done && edge.hasFollowUp(tl_out.d.bits)
|
|
grantackq.io.enq.bits := edge.GrantAck(tl_out.d.bits)
|
|
tl_out.e <> grantackq.io.deq
|
|
assert(!grantackq.io.enq.valid || grantackq.io.enq.ready, "Too many Grants received by dcache.")
|
|
when (d_done) { replacer.miss }
|
|
|
|
// Handle an incoming TileLink Probe message
|
|
val block_probe = releaseInFlight || lrscValid || (s2_valid_hit && s2_lr)
|
|
metaReadArb.io.in(1).valid := tl_out.b.valid && !block_probe
|
|
tl_out.b.ready := metaReadArb.io.in(1).ready && !block_probe && !s1_valid && (!s2_valid || s2_valid_hit)
|
|
metaReadArb.io.in(1).bits.idx := tl_out.b.bits.address(idxMSB, idxLSB)
|
|
metaReadArb.io.in(1).bits.way_en := ~UInt(0, nWays)
|
|
|
|
// release
|
|
val (_, c_last, releaseDone, c_count) = edge.count(tl_out.c)
|
|
val releaseRejected = tl_out.c.valid && !tl_out.c.ready
|
|
val s1_release_data_valid = Reg(next = dataArb.io.in(2).fire())
|
|
val s2_release_data_valid = Reg(next = s1_release_data_valid && !releaseRejected)
|
|
val releaseDataBeat = Cat(UInt(0), c_count) + Mux(releaseRejected, UInt(0), s1_release_data_valid + Cat(UInt(0), s2_release_data_valid))
|
|
|
|
val nackResponseMessage = edge.ProbeAck(
|
|
b = probe_bits,
|
|
reportPermissions = TLPermissions.NtoN)
|
|
|
|
val voluntaryReleaseMessage = if (edge.manager.anySupportAcquire) {
|
|
edge.Release(
|
|
fromSource = UInt(maxUncachedInFlight - 1),
|
|
toAddress = probe_bits.address,
|
|
lgSize = lgCacheBlockBytes,
|
|
shrinkPermissions = s2_shrink_param,
|
|
data = s2_data)._2
|
|
} else {
|
|
Wire(new TLBundleC(edge.bundle))
|
|
}
|
|
|
|
val probeResponseMessage = Mux(!s2_prb_ack_data,
|
|
edge.ProbeAck(
|
|
b = probe_bits,
|
|
reportPermissions = s2_report_param),
|
|
edge.ProbeAck(
|
|
b = probe_bits,
|
|
reportPermissions = s2_report_param,
|
|
data = s2_data))
|
|
|
|
tl_out.c.valid := s2_release_data_valid
|
|
tl_out.c.bits := nackResponseMessage
|
|
val newCoh = Wire(init = probeNewCoh)
|
|
releaseWay := s2_probe_way
|
|
|
|
when (s2_victimize && s2_victim_dirty) {
|
|
assert(!(s2_valid && s2_hit_valid))
|
|
release_state := s_voluntary_writeback
|
|
probe_bits.address := Cat(s2_victim_tag, s2_req.addr(idxMSB, idxLSB)) << idxLSB
|
|
}
|
|
when (s2_probe) {
|
|
when (s2_prb_ack_data) { release_state := s_probe_rep_dirty }
|
|
.elsewhen (s2_probe_state.isValid()) { release_state := s_probe_rep_clean }
|
|
.otherwise {
|
|
tl_out.c.valid := true
|
|
release_state := s_probe_rep_miss
|
|
}
|
|
}
|
|
when (releaseDone) { release_state := s_ready }
|
|
when (release_state.isOneOf(s_probe_rep_miss, s_probe_rep_clean)) {
|
|
tl_out.c.valid := true
|
|
}
|
|
when (release_state.isOneOf(s_probe_rep_clean, s_probe_rep_dirty)) {
|
|
tl_out.c.bits := probeResponseMessage
|
|
when (releaseDone) { release_state := s_probe_write_meta }
|
|
}
|
|
when (release_state.isOneOf(s_voluntary_writeback, s_voluntary_write_meta)) {
|
|
tl_out.c.bits := voluntaryReleaseMessage
|
|
newCoh := voluntaryNewCoh
|
|
releaseWay := s2_victim_way
|
|
when (releaseDone) {
|
|
release_state := s_voluntary_write_meta
|
|
release_ack_wait := true
|
|
}
|
|
}
|
|
when (s2_probe && !tl_out.c.fire()) { s1_nack := true }
|
|
tl_out.c.bits.address := probe_bits.address
|
|
tl_out.c.bits.data := s2_data
|
|
|
|
dataArb.io.in(2).valid := inWriteback && releaseDataBeat < refillCycles
|
|
dataArb.io.in(2).bits.write := false
|
|
dataArb.io.in(2).bits.addr := tl_out.c.bits.address | (releaseDataBeat(log2Up(refillCycles)-1,0) << rowOffBits)
|
|
dataArb.io.in(2).bits.way_en := ~UInt(0, nWays)
|
|
|
|
metaWriteArb.io.in(2).valid := release_state.isOneOf(s_voluntary_write_meta, s_probe_write_meta)
|
|
metaWriteArb.io.in(2).bits.way_en := releaseWay
|
|
metaWriteArb.io.in(2).bits.idx := tl_out.c.bits.address(idxMSB, idxLSB)
|
|
metaWriteArb.io.in(2).bits.data.coh := newCoh
|
|
metaWriteArb.io.in(2).bits.data.tag := tl_out.c.bits.address(paddrBits-1, untagBits)
|
|
when (metaWriteArb.io.in(2).fire()) { release_state := s_ready }
|
|
|
|
// cached response
|
|
io.cpu.resp.valid := s2_valid_hit
|
|
io.cpu.resp.bits <> s2_req
|
|
io.cpu.resp.bits.has_data := s2_read
|
|
io.cpu.resp.bits.replay := false
|
|
io.cpu.ordered := !(s1_valid || s2_valid || cached_grant_wait || uncachedInFlight.asUInt.orR)
|
|
|
|
// uncached response
|
|
io.cpu.replay_next := tl_out.d.fire() && grantIsUncached
|
|
val doUncachedResp = Reg(next = io.cpu.replay_next)
|
|
when (doUncachedResp) {
|
|
assert(!s2_valid_hit)
|
|
io.cpu.resp.valid := true
|
|
io.cpu.resp.bits.replay := true
|
|
}
|
|
|
|
// load data subword mux/sign extension
|
|
val s2_word_idx = s2_req.addr.extract(log2Up(rowBits/8)-1, log2Up(wordBytes))
|
|
val s2_data_word = s2_data >> Cat(s2_word_idx, UInt(0, log2Up(coreDataBits)))
|
|
val loadgen = new LoadGen(s2_req.typ, mtSigned(s2_req.typ), s2_req.addr, s2_data_word, s2_sc, wordBytes)
|
|
io.cpu.resp.bits.data := loadgen.data | s2_sc_fail
|
|
io.cpu.resp.bits.data_word_bypass := loadgen.wordData
|
|
io.cpu.resp.bits.store_data := pstore1_data
|
|
|
|
// AMOs
|
|
if (usingAtomics) {
|
|
val amoalu = Module(new AMOALU(xLen))
|
|
amoalu.io.addr := pstore1_addr
|
|
amoalu.io.cmd := pstore1_cmd
|
|
amoalu.io.typ := pstore1_typ
|
|
amoalu.io.lhs := s2_data_word
|
|
amoalu.io.rhs := pstore1_data
|
|
pstore1_storegen_data := amoalu.io.out
|
|
} else {
|
|
assert(!(s1_valid_masked && s1_read && s1_write), "unsupported D$ operation")
|
|
}
|
|
|
|
// flushes
|
|
val flushed = Reg(init=Bool(true))
|
|
val flushing = Reg(init=Bool(false))
|
|
val flushCounter = Counter(nSets * nWays)
|
|
when (tl_out.a.fire() && !s2_uncached) { flushed := false }
|
|
when (s2_valid_masked && s2_req.cmd === M_FLUSH_ALL) {
|
|
io.cpu.s2_nack := !flushed
|
|
when (!flushed) {
|
|
flushing := !release_ack_wait && !uncachedInFlight.asUInt.orR
|
|
}
|
|
}
|
|
s1_flush_valid := metaReadArb.io.in(0).fire() && !s1_flush_valid && !s2_flush_valid && release_state === s_ready && !release_ack_wait
|
|
metaReadArb.io.in(0).valid := flushing
|
|
metaReadArb.io.in(0).bits.idx := flushCounter.value
|
|
metaReadArb.io.in(0).bits.way_en := ~UInt(0, nWays)
|
|
when (flushing) {
|
|
s1_victim_way := flushCounter.value >> log2Up(nSets)
|
|
when (s2_flush_valid) {
|
|
when (flushCounter.inc()) {
|
|
flushed := true
|
|
}
|
|
}
|
|
when (flushed && release_state === s_ready && !release_ack_wait) {
|
|
flushing := false
|
|
}
|
|
}
|
|
}
|