xref: /XiangShan/src/main/scala/xiangshan/mem/lsqueue/StoreQueue.scala (revision a4d1b2d1ae4c6149f55fbcac48749c08714bfe0c)
1/***************************************************************************************
2* Copyright (c) 2020-2021 Institute of Computing Technology, Chinese Academy of Sciences
3* Copyright (c) 2020-2021 Peng Cheng Laboratory
4*
5* XiangShan is licensed under Mulan PSL v2.
6* You can use this software according to the terms and conditions of the Mulan PSL v2.
7* You may obtain a copy of Mulan PSL v2 at:
8*          http://license.coscl.org.cn/MulanPSL2
9*
10* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
11* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
12* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
13*
14* See the Mulan PSL v2 for more details.
15***************************************************************************************/
16
17package xiangshan.mem
18
19import chisel3._
20import chisel3.util._
21import difftest._
22import difftest.common.DifftestMem
23import org.chipsalliance.cde.config.Parameters
24import utility._
25import utils._
26import xiangshan._
27import xiangshan.cache._
28import xiangshan.cache.{DCacheLineIO, DCacheWordIO, MemoryOpConstants}
29import xiangshan.backend._
30import xiangshan.backend.rob.{RobLsqIO, RobPtr}
31import xiangshan.backend.Bundles.{DynInst, MemExuOutput}
32import xiangshan.backend.decode.isa.bitfield.{Riscv32BitInst, XSInstBitFields}
33import xiangshan.backend.fu.FuConfig._
34import xiangshan.backend.fu.FuType
35
36class SqPtr(implicit p: Parameters) extends CircularQueuePtr[SqPtr](
37  p => p(XSCoreParamsKey).StoreQueueSize
38){
39}
40
41object SqPtr {
42  def apply(f: Bool, v: UInt)(implicit p: Parameters): SqPtr = {
43    val ptr = Wire(new SqPtr)
44    ptr.flag := f
45    ptr.value := v
46    ptr
47  }
48}
49
50class SqEnqIO(implicit p: Parameters) extends MemBlockBundle {
51  val canAccept = Output(Bool())
52  val lqCanAccept = Input(Bool())
53  val needAlloc = Vec(LSQEnqWidth, Input(Bool()))
54  val req = Vec(LSQEnqWidth, Flipped(ValidIO(new DynInst)))
55  val resp = Vec(LSQEnqWidth, Output(new SqPtr))
56}
57
58class DataBufferEntry (implicit p: Parameters)  extends DCacheBundle {
59  val addr   = UInt(PAddrBits.W)
60  val vaddr  = UInt(VAddrBits.W)
61  val data   = UInt(VLEN.W)
62  val mask   = UInt((VLEN/8).W)
63  val wline = Bool()
64  val sqPtr  = new SqPtr
65  val prefetch = Bool()
66  val vecValid = Bool()
67}
68
69class StoreExceptionBuffer(implicit p: Parameters) extends XSModule with HasCircularQueuePtrHelper {
70  val io = IO(new Bundle() {
71    val redirect = Flipped(ValidIO(new Redirect))
72    val storeAddrIn = Vec(StorePipelineWidth + VecStorePipelineWidth, Flipped(ValidIO(new LsPipelineBundle())))
73    val exceptionAddr = new ExceptionAddrIO
74  })
75
76  val req_valid = RegInit(false.B)
77  val req = Reg(new LsPipelineBundle())
78
79  // enqueue
80  // S1:
81  val s1_req = VecInit(io.storeAddrIn.map(_.bits))
82  val s1_valid = VecInit(io.storeAddrIn.map(_.valid))
83
84  // S2: delay 1 cycle
85  val s2_req = RegNext(s1_req)
86  val s2_valid = (0 until StorePipelineWidth + VecStorePipelineWidth).map(i =>
87    RegNext(s1_valid(i)) &&
88      !s2_req(i).uop.robIdx.needFlush(RegNext(io.redirect)) &&
89      !s2_req(i).uop.robIdx.needFlush(io.redirect)
90  )
91  val s2_has_exception = s2_req.map(x => ExceptionNO.selectByFu(x.uop.exceptionVec, StaCfg).asUInt.orR)
92
93  val s2_enqueue = Wire(Vec(StorePipelineWidth + VecStorePipelineWidth, Bool()))
94  for (w <- 0 until StorePipelineWidth + VecStorePipelineWidth) {
95    s2_enqueue(w) := s2_valid(w) && s2_has_exception(w)
96  }
97
98  when (req_valid && req.uop.robIdx.needFlush(io.redirect)) {
99    req_valid := s2_enqueue.asUInt.orR
100  }.elsewhen (s2_enqueue.asUInt.orR) {
101    req_valid := req_valid || true.B
102  }
103
104  def selectOldest[T <: LsPipelineBundle](valid: Seq[Bool], bits: Seq[T]): (Seq[Bool], Seq[T]) = {
105    assert(valid.length == bits.length)
106    if (valid.length == 0 || valid.length == 1) {
107      (valid, bits)
108    } else if (valid.length == 2) {
109      val res = Seq.fill(2)(Wire(Valid(chiselTypeOf(bits(0)))))
110      for (i <- res.indices) {
111        res(i).valid := valid(i)
112        res(i).bits := bits(i)
113      }
114      val oldest = Mux(valid(0) && valid(1),
115        Mux(isAfter(bits(0).uop.robIdx, bits(1).uop.robIdx) ||
116          (isNotBefore(bits(0).uop.robIdx, bits(1).uop.robIdx) && bits(0).uop.uopIdx > bits(1).uop.uopIdx), res(1), res(0)),
117        Mux(valid(0) && !valid(1), res(0), res(1)))
118      (Seq(oldest.valid), Seq(oldest.bits))
119    } else {
120      val left = selectOldest(valid.take(valid.length / 2), bits.take(bits.length / 2))
121      val right = selectOldest(valid.takeRight(valid.length - (valid.length / 2)), bits.takeRight(bits.length - (bits.length / 2)))
122      selectOldest(left._1 ++ right._1, left._2 ++ right._2)
123    }
124  }
125
126  val reqSel = selectOldest(s2_enqueue, s2_req)
127
128  when (req_valid) {
129    req := Mux(reqSel._1(0) && isAfter(req.uop.robIdx, reqSel._2(0).uop.robIdx) ||
130      (isNotBefore(req.uop.robIdx, reqSel._2(0).uop.robIdx) && req.uop.uopIdx > reqSel._2(0).uop.uopIdx), reqSel._2(0), req)
131  } .elsewhen (s2_enqueue.asUInt.orR) {
132    req := reqSel._2(0)
133  }
134
135  io.exceptionAddr.vaddr  := req.vaddr
136  io.exceptionAddr.gpaddr := req.gpaddr
137  io.exceptionAddr.vstart := req.uop.vpu.vstart
138  io.exceptionAddr.vl     := req.uop.vpu.vl
139}
140
141// Store Queue
142class StoreQueue(implicit p: Parameters) extends XSModule
143  with HasDCacheParameters
144  with HasCircularQueuePtrHelper
145  with HasPerfEvents
146  with HasVLSUParameters {
147  val io = IO(new Bundle() {
148    val hartId = Input(UInt(hartIdLen.W))
149    val enq = new SqEnqIO
150    val brqRedirect = Flipped(ValidIO(new Redirect))
151    val vecFeedback = Vec(VecLoadPipelineWidth, Flipped(ValidIO(new FeedbackToLsqIO)))
152    val storeAddrIn = Vec(StorePipelineWidth, Flipped(Valid(new LsPipelineBundle))) // store addr, data is not included
153    val storeAddrInRe = Vec(StorePipelineWidth, Input(new LsPipelineBundle())) // store more mmio and exception
154    val storeDataIn = Vec(StorePipelineWidth, Flipped(Valid(new MemExuOutput(isVector = true)))) // store data, send to sq from rs
155    val storeMaskIn = Vec(StorePipelineWidth, Flipped(Valid(new StoreMaskBundle))) // store mask, send to sq from rs
156    val sbuffer = Vec(EnsbufferWidth, Decoupled(new DCacheWordReqWithVaddrAndPfFlag)) // write committed store to sbuffer
157    val sbufferVecDifftestInfo = Vec(EnsbufferWidth, Decoupled(new DynInst)) // The vector store difftest needs is, write committed store to sbuffer
158    val uncacheOutstanding = Input(Bool())
159    val mmioStout = DecoupledIO(new MemExuOutput) // writeback uncached store
160    val vecmmioStout = DecoupledIO(new MemExuOutput(isVector = true))
161    val forward = Vec(LoadPipelineWidth, Flipped(new PipeLoadForwardQueryIO))
162    // TODO: scommit is only for scalar store
163    val rob = Flipped(new RobLsqIO)
164    val uncache = new UncacheWordIO
165    // val refill = Flipped(Valid(new DCacheLineReq ))
166    val exceptionAddr = new ExceptionAddrIO
167    val sqEmpty = Output(Bool())
168    val stAddrReadySqPtr = Output(new SqPtr)
169    val stAddrReadyVec = Output(Vec(StoreQueueSize, Bool()))
170    val stDataReadySqPtr = Output(new SqPtr)
171    val stDataReadyVec = Output(Vec(StoreQueueSize, Bool()))
172    val stIssuePtr = Output(new SqPtr)
173    val sqDeqPtr = Output(new SqPtr)
174    val sqFull = Output(Bool())
175    val sqCancelCnt = Output(UInt(log2Up(StoreQueueSize + 1).W))
176    val sqDeq = Output(UInt(log2Ceil(EnsbufferWidth + 1).W))
177    val force_write = Output(Bool())
178  })
179
180  println("StoreQueue: size:" + StoreQueueSize)
181
182  // data modules
183  val uop = Reg(Vec(StoreQueueSize, new DynInst))
184  // val data = Reg(Vec(StoreQueueSize, new LsqEntry))
185  val dataModule = Module(new SQDataModule(
186    numEntries = StoreQueueSize,
187    numRead = EnsbufferWidth,
188    numWrite = StorePipelineWidth,
189    numForward = LoadPipelineWidth
190  ))
191  dataModule.io := DontCare
192  val paddrModule = Module(new SQAddrModule(
193    dataWidth = PAddrBits,
194    numEntries = StoreQueueSize,
195    numRead = EnsbufferWidth,
196    numWrite = StorePipelineWidth,
197    numForward = LoadPipelineWidth
198  ))
199  paddrModule.io := DontCare
200  val vaddrModule = Module(new SQAddrModule(
201    dataWidth = VAddrBits,
202    numEntries = StoreQueueSize,
203    numRead = EnsbufferWidth, // sbuffer; badvaddr will be sent from exceptionBuffer
204    numWrite = StorePipelineWidth,
205    numForward = LoadPipelineWidth
206  ))
207  vaddrModule.io := DontCare
208  val dataBuffer = Module(new DatamoduleResultBuffer(new DataBufferEntry))
209  val difftestBuffer = if (env.EnableDifftest) Some(Module(new DatamoduleResultBuffer(new DynInst))) else None
210  val exceptionBuffer = Module(new StoreExceptionBuffer)
211  exceptionBuffer.io.redirect := io.brqRedirect
212  exceptionBuffer.io.exceptionAddr.isStore := DontCare
213  // vlsu exception!
214  for (i <- 0 until VecStorePipelineWidth) {
215    exceptionBuffer.io.storeAddrIn(StorePipelineWidth + i).valid               := io.vecFeedback(i).valid && io.vecFeedback(i).bits.feedback(VecFeedbacks.FLUSH) // have exception
216    exceptionBuffer.io.storeAddrIn(StorePipelineWidth + i).bits                := DontCare
217    exceptionBuffer.io.storeAddrIn(StorePipelineWidth + i).bits.vaddr          := io.vecFeedback(i).bits.vaddr
218    exceptionBuffer.io.storeAddrIn(StorePipelineWidth + i).bits.uop.uopIdx     := io.vecFeedback(i).bits.uopidx
219    exceptionBuffer.io.storeAddrIn(StorePipelineWidth + i).bits.uop.robIdx     := io.vecFeedback(i).bits.robidx
220    exceptionBuffer.io.storeAddrIn(StorePipelineWidth + i).bits.uop.vpu.vstart := io.vecFeedback(i).bits.vstart
221    exceptionBuffer.io.storeAddrIn(StorePipelineWidth + i).bits.uop.vpu.vl     := io.vecFeedback(i).bits.vl
222    exceptionBuffer.io.storeAddrIn(StorePipelineWidth + i).bits.uop.exceptionVec     := io.vecFeedback(i).bits.exceptionVec
223  }
224
225
226  val debug_paddr = Reg(Vec(StoreQueueSize, UInt((PAddrBits).W)))
227  val debug_vaddr = Reg(Vec(StoreQueueSize, UInt((VAddrBits).W)))
228  val debug_data = Reg(Vec(StoreQueueSize, UInt((XLEN).W)))
229
230  // state & misc
231  val allocated = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // sq entry has been allocated
232  val addrvalid = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // non-mmio addr is valid
233  val datavalid = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // non-mmio data is valid
234  val allvalid  = VecInit((0 until StoreQueueSize).map(i => addrvalid(i) && datavalid(i))) // non-mmio data & addr is valid
235  val committed = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // inst has been committed by rob
236  val pending = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // mmio pending: inst is an mmio inst, it will not be executed until it reachs the end of rob
237  val mmio = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // mmio: inst is an mmio inst
238  val atomic = RegInit(VecInit(List.fill(StoreQueueSize)(false.B)))
239  val prefetch = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // need prefetch when committing this store to sbuffer?
240  val isVec = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // vector store instruction
241  //val vec_lastuop = Reg(Vec(StoreQueueSize, Bool())) // last uop of vector store instruction
242  val vecMbCommit = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // vector store committed from merge buffer to rob
243  val vecDataValid = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // vector store need write to sbuffer
244  // val vec_robCommit = Reg(Vec(StoreQueueSize, Bool())) // vector store committed by rob
245  // val vec_secondInv = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // Vector unit-stride, second entry is invalid
246
247  // ptr
248  val enqPtrExt = RegInit(VecInit((0 until io.enq.req.length).map(_.U.asTypeOf(new SqPtr))))
249  val rdataPtrExt = RegInit(VecInit((0 until EnsbufferWidth).map(_.U.asTypeOf(new SqPtr))))
250  val deqPtrExt = RegInit(VecInit((0 until EnsbufferWidth).map(_.U.asTypeOf(new SqPtr))))
251  val cmtPtrExt = RegInit(VecInit((0 until CommitWidth).map(_.U.asTypeOf(new SqPtr))))
252  val addrReadyPtrExt = RegInit(0.U.asTypeOf(new SqPtr))
253  val dataReadyPtrExt = RegInit(0.U.asTypeOf(new SqPtr))
254
255  val enqPtr = enqPtrExt(0).value
256  val deqPtr = deqPtrExt(0).value
257  val cmtPtr = cmtPtrExt(0).value
258
259  val validCount = distanceBetween(enqPtrExt(0), deqPtrExt(0))
260  val allowEnqueue = validCount <= (StoreQueueSize - LSQStEnqWidth).U
261
262  val deqMask = UIntToMask(deqPtr, StoreQueueSize)
263  val enqMask = UIntToMask(enqPtr, StoreQueueSize)
264
265  // TODO: count commit numbers for scalar / vector store separately
266  val scalarCommitCount = RegInit(0.U(log2Ceil(StoreQueueSize + 1).W))
267  val scalarCommitted = WireInit(0.U(log2Ceil(CommitWidth + 1).W))
268  val vecCommitted = WireInit(0.U(log2Ceil(CommitWidth + 1).W))
269  val commitCount = WireInit(0.U(log2Ceil(CommitWidth + 1).W))
270  val scommit = RegNext(io.rob.scommit)
271
272  scalarCommitCount := scalarCommitCount + scommit - scalarCommitted
273
274  // store can be committed by ROB
275  io.rob.mmio := DontCare
276  io.rob.uop := DontCare
277
278  // Read dataModule
279  assert(EnsbufferWidth <= 2)
280  // rdataPtrExtNext and rdataPtrExtNext+1 entry will be read from dataModule
281  val rdataPtrExtNext = WireInit(Mux(dataBuffer.io.enq(1).fire,
282    VecInit(rdataPtrExt.map(_ + 2.U)),
283    Mux(dataBuffer.io.enq(0).fire || io.mmioStout.fire || io.vecmmioStout.fire,
284      VecInit(rdataPtrExt.map(_ + 1.U)),
285      rdataPtrExt
286    )
287  ))
288
289  // deqPtrExtNext traces which inst is about to leave store queue
290  //
291  // io.sbuffer(i).fire is RegNexted, as sbuffer data write takes 2 cycles.
292  // Before data write finish, sbuffer is unable to provide store to load
293  // forward data. As an workaround, deqPtrExt and allocated flag update
294  // is delayed so that load can get the right data from store queue.
295  //
296  // Modify deqPtrExtNext and io.sqDeq with care!
297  val deqPtrExtNext = Mux(RegNext(io.sbuffer(1).fire),
298    VecInit(deqPtrExt.map(_ + 2.U)),
299    Mux((RegNext(io.sbuffer(0).fire)) || io.mmioStout.fire || io.vecmmioStout.fire,
300      VecInit(deqPtrExt.map(_ + 1.U)),
301      deqPtrExt
302    )
303  )
304  io.sqDeq := RegNext(Mux(RegNext(io.sbuffer(1).fire), 2.U,
305    Mux((RegNext(io.sbuffer(0).fire)) || io.mmioStout.fire || io.vecmmioStout.fire, 1.U, 0.U)
306  ))
307  assert(!RegNext(RegNext(io.sbuffer(0).fire) && (io.mmioStout.fire || io.vecmmioStout.fire)))
308
309  for (i <- 0 until EnsbufferWidth) {
310    dataModule.io.raddr(i) := rdataPtrExtNext(i).value
311    paddrModule.io.raddr(i) := rdataPtrExtNext(i).value
312    vaddrModule.io.raddr(i) := rdataPtrExtNext(i).value
313  }
314
315  /**
316    * Enqueue at dispatch
317    *
318    * Currently, StoreQueue only allows enqueue when #emptyEntries > EnqWidth
319    */
320  io.enq.canAccept := allowEnqueue
321  val canEnqueue = io.enq.req.map(_.valid)
322  val enqCancel = io.enq.req.map(_.bits.robIdx.needFlush(io.brqRedirect))
323  val vStoreFlow = io.enq.req.map(_.bits.numLsElem)
324  val validVStoreFlow = vStoreFlow.zipWithIndex.map{case (vLoadFlowNumItem, index) => Mux(!RegNext(io.brqRedirect.valid) && io.enq.canAccept && io.enq.lqCanAccept && canEnqueue(index), vLoadFlowNumItem, 0.U)}
325  val validVStoreOffset = vStoreFlow.zip(io.enq.needAlloc).map{case (flow, needAllocItem) => Mux(needAllocItem, flow, 0.U)}
326  val validVStoreOffsetRShift = 0.U +: validVStoreOffset.take(vStoreFlow.length - 1)
327
328  for (i <- 0 until io.enq.req.length) {
329    val sqIdx = enqPtrExt(0) + validVStoreOffsetRShift.take(i + 1).reduce(_ + _)
330    val index = io.enq.req(i).bits.sqIdx
331    val enqInstr = io.enq.req(i).bits.instr.asTypeOf(new XSInstBitFields)
332    when (canEnqueue(i) && !enqCancel(i)) {
333      for (j <- 0 until VecMemDispatchMaxNumber) {
334        when (j.U < validVStoreOffset(i)) {
335          uop((index + j.U).value) := io.enq.req(i).bits
336          // NOTE: the index will be used when replay
337          uop((index + j.U).value).sqIdx := sqIdx + j.U
338          allocated((index + j.U).value) := true.B
339          datavalid((index + j.U).value) := false.B
340          addrvalid((index + j.U).value) := false.B
341          committed((index + j.U).value) := false.B
342          pending((index + j.U).value) := false.B
343          prefetch((index + j.U).value) := false.B
344          mmio((index + j.U).value) := false.B
345          isVec((index + j.U).value) := enqInstr.isVecStore // check vector store by the encoding of inst
346          vecMbCommit((index + j.U).value) := false.B
347          vecDataValid((index + j.U).value) := false.B
348          XSError(!io.enq.canAccept || !io.enq.lqCanAccept, s"must accept $i\n")
349          XSError(index.value =/= sqIdx.value, s"must be the same entry $i\n")
350        }
351      }
352    }
353    io.enq.resp(i) := sqIdx
354  }
355  XSDebug(p"(ready, valid): ${io.enq.canAccept}, ${Binary(Cat(io.enq.req.map(_.valid)))}\n")
356
357  /**
358    * Update addr/dataReadyPtr when issue from rs
359    */
360  // update issuePtr
361  val IssuePtrMoveStride = 4
362  require(IssuePtrMoveStride >= 2)
363
364  val addrReadyLookupVec = (0 until IssuePtrMoveStride).map(addrReadyPtrExt + _.U)
365  val addrReadyLookup = addrReadyLookupVec.map(ptr => allocated(ptr.value) &&
366   (mmio(ptr.value) || addrvalid(ptr.value) || vecMbCommit(ptr.value))
367    && ptr =/= enqPtrExt(0))
368  val nextAddrReadyPtr = addrReadyPtrExt + PriorityEncoder(VecInit(addrReadyLookup.map(!_) :+ true.B))
369  addrReadyPtrExt := nextAddrReadyPtr
370
371  (0 until StoreQueueSize).map(i => {
372    io.stAddrReadyVec(i) := RegNext(allocated(i) && (mmio(i) || addrvalid(i)))
373  })
374
375  when (io.brqRedirect.valid) {
376    addrReadyPtrExt := Mux(
377      isAfter(cmtPtrExt(0), deqPtrExt(0)),
378      cmtPtrExt(0),
379      deqPtrExtNext(0) // for mmio insts, deqPtr may be ahead of cmtPtr
380    )
381  }
382
383  io.stAddrReadySqPtr := addrReadyPtrExt
384
385  // update
386  val dataReadyLookupVec = (0 until IssuePtrMoveStride).map(dataReadyPtrExt + _.U)
387  val dataReadyLookup = dataReadyLookupVec.map(ptr => allocated(ptr.value) &&
388   (mmio(ptr.value) || datavalid(ptr.value) || vecMbCommit(ptr.value))
389    && ptr =/= enqPtrExt(0))
390  val nextDataReadyPtr = dataReadyPtrExt + PriorityEncoder(VecInit(dataReadyLookup.map(!_) :+ true.B))
391  dataReadyPtrExt := nextDataReadyPtr
392
393  (0 until StoreQueueSize).map(i => {
394    io.stDataReadyVec(i) := RegNext(allocated(i) && (mmio(i) || datavalid(i)))
395  })
396
397  when (io.brqRedirect.valid) {
398    dataReadyPtrExt := Mux(
399      isAfter(cmtPtrExt(0), deqPtrExt(0)),
400      cmtPtrExt(0),
401      deqPtrExtNext(0) // for mmio insts, deqPtr may be ahead of cmtPtr
402    )
403  }
404
405  io.stDataReadySqPtr := dataReadyPtrExt
406  io.stIssuePtr := enqPtrExt(0)
407  io.sqDeqPtr := deqPtrExt(0)
408
409  /**
410    * Writeback store from store units
411    *
412    * Most store instructions writeback to regfile in the previous cycle.
413    * However,
414    *   (1) For an mmio instruction with exceptions, we need to mark it as addrvalid
415    * (in this way it will trigger an exception when it reaches ROB's head)
416    * instead of pending to avoid sending them to lower level.
417    *   (2) For an mmio instruction without exceptions, we mark it as pending.
418    * When the instruction reaches ROB's head, StoreQueue sends it to uncache channel.
419    * Upon receiving the response, StoreQueue writes back the instruction
420    * through arbiter with store units. It will later commit as normal.
421    */
422
423  // Write addr to sq
424  for (i <- 0 until StorePipelineWidth) {
425    paddrModule.io.wen(i) := false.B
426    vaddrModule.io.wen(i) := false.B
427    dataModule.io.mask.wen(i) := false.B
428    val stWbIndex = io.storeAddrIn(i).bits.uop.sqIdx.value
429    exceptionBuffer.io.storeAddrIn(i).valid := io.storeAddrIn(i).fire && !io.storeAddrIn(i).bits.miss && !io.storeAddrIn(i).bits.isvec
430    exceptionBuffer.io.storeAddrIn(i).bits := io.storeAddrIn(i).bits
431
432    when (io.storeAddrIn(i).fire) {
433      val addr_valid = !io.storeAddrIn(i).bits.miss
434      addrvalid(stWbIndex) := addr_valid //!io.storeAddrIn(i).bits.mmio
435      // pending(stWbIndex) := io.storeAddrIn(i).bits.mmio
436
437      paddrModule.io.waddr(i) := stWbIndex
438      paddrModule.io.wdata(i) := io.storeAddrIn(i).bits.paddr
439      paddrModule.io.wmask(i) := io.storeAddrIn(i).bits.mask
440      paddrModule.io.wlineflag(i) := io.storeAddrIn(i).bits.wlineflag
441      paddrModule.io.wen(i) := true.B
442
443      vaddrModule.io.waddr(i) := stWbIndex
444      vaddrModule.io.wdata(i) := io.storeAddrIn(i).bits.vaddr
445      vaddrModule.io.wmask(i) := io.storeAddrIn(i).bits.mask
446      vaddrModule.io.wlineflag(i) := io.storeAddrIn(i).bits.wlineflag
447      vaddrModule.io.wen(i) := true.B
448
449      debug_paddr(paddrModule.io.waddr(i)) := paddrModule.io.wdata(i)
450
451      // mmio(stWbIndex) := io.storeAddrIn(i).bits.mmio
452
453      uop(stWbIndex) := io.storeAddrIn(i).bits.uop
454      uop(stWbIndex).debugInfo := io.storeAddrIn(i).bits.uop.debugInfo
455
456      vecDataValid(stWbIndex) := io.storeAddrIn(i).bits.isvec
457
458      XSInfo("store addr write to sq idx %d pc 0x%x miss:%d vaddr %x paddr %x mmio %x isvec %x\n",
459        io.storeAddrIn(i).bits.uop.sqIdx.value,
460        io.storeAddrIn(i).bits.uop.pc,
461        io.storeAddrIn(i).bits.miss,
462        io.storeAddrIn(i).bits.vaddr,
463        io.storeAddrIn(i).bits.paddr,
464        io.storeAddrIn(i).bits.mmio,
465        io.storeAddrIn(i).bits.isvec
466      )
467    }
468
469    // re-replinish mmio, for pma/pmp will get mmio one cycle later
470    val storeAddrInFireReg = RegNext(io.storeAddrIn(i).fire && !io.storeAddrIn(i).bits.miss)
471    val stWbIndexReg = RegNext(stWbIndex)
472    when (storeAddrInFireReg) {
473      pending(stWbIndexReg) := io.storeAddrInRe(i).mmio
474      mmio(stWbIndexReg) := io.storeAddrInRe(i).mmio
475      atomic(stWbIndexReg) := io.storeAddrInRe(i).atomic
476    }
477    // dcache miss info (one cycle later than storeIn)
478    // if dcache report a miss in sta pipeline, this store will trigger a prefetch when committing to sbuffer (if EnableAtCommitMissTrigger)
479    when (storeAddrInFireReg) {
480      prefetch(stWbIndexReg) := io.storeAddrInRe(i).miss
481    }
482
483    when(vaddrModule.io.wen(i)){
484      debug_vaddr(vaddrModule.io.waddr(i)) := vaddrModule.io.wdata(i)
485    }
486  }
487
488  // Write data to sq
489  // Now store data pipeline is actually 2 stages
490  for (i <- 0 until StorePipelineWidth) {
491    dataModule.io.data.wen(i) := false.B
492    val stWbIndex = io.storeDataIn(i).bits.uop.sqIdx.value
493    val isVec     = FuType.isVStore(io.storeDataIn(i).bits.uop.fuType)
494    // sq data write takes 2 cycles:
495    // sq data write s0
496    when (io.storeDataIn(i).fire) {
497      // send data write req to data module
498      dataModule.io.data.waddr(i) := stWbIndex
499      dataModule.io.data.wdata(i) := Mux(io.storeDataIn(i).bits.uop.fuOpType === LSUOpType.cbo_zero,
500        0.U,
501        Mux(isVec,
502          io.storeDataIn(i).bits.data,
503          genVWdata(io.storeDataIn(i).bits.data, io.storeDataIn(i).bits.uop.fuOpType(2,0)))
504      )
505      dataModule.io.data.wen(i) := true.B
506
507      debug_data(dataModule.io.data.waddr(i)) := dataModule.io.data.wdata(i)
508
509      XSInfo("store data write to sq idx %d pc 0x%x data %x -> %x\n",
510        io.storeDataIn(i).bits.uop.sqIdx.value,
511        io.storeDataIn(i).bits.uop.pc,
512        io.storeDataIn(i).bits.data,
513        dataModule.io.data.wdata(i)
514      )
515    }
516    // sq data write s1
517    when (
518      RegNext(io.storeDataIn(i).fire)
519      // && !RegNext(io.storeDataIn(i).bits.uop).robIdx.needFlush(io.brqRedirect)
520    ) {
521      datavalid(RegNext(stWbIndex)) := true.B
522    }
523  }
524
525  // Write mask to sq
526  for (i <- 0 until StorePipelineWidth) {
527    // sq mask write s0
528    when (io.storeMaskIn(i).fire) {
529      // send data write req to data module
530      dataModule.io.mask.waddr(i) := io.storeMaskIn(i).bits.sqIdx.value
531      dataModule.io.mask.wdata(i) := io.storeMaskIn(i).bits.mask
532      dataModule.io.mask.wen(i) := true.B
533    }
534  }
535
536  /**
537    * load forward query
538    *
539    * Check store queue for instructions that is older than the load.
540    * The response will be valid at the next cycle after req.
541    */
542  // check over all lq entries and forward data from the first matched store
543  for (i <- 0 until LoadPipelineWidth) {
544    // Compare deqPtr (deqPtr) and forward.sqIdx, we have two cases:
545    // (1) if they have the same flag, we need to check range(tail, sqIdx)
546    // (2) if they have different flags, we need to check range(tail, VirtualLoadQueueSize) and range(0, sqIdx)
547    // Forward1: Mux(same_flag, range(tail, sqIdx), range(tail, VirtualLoadQueueSize))
548    // Forward2: Mux(same_flag, 0.U,                   range(0, sqIdx)    )
549    // i.e. forward1 is the target entries with the same flag bits and forward2 otherwise
550    val differentFlag = deqPtrExt(0).flag =/= io.forward(i).sqIdx.flag
551    val forwardMask = io.forward(i).sqIdxMask
552    // all addrvalid terms need to be checked
553    // Real Vaild: all scalar stores, and vector store with (!inactive && !secondInvalid)
554    val addrRealValidVec = WireInit(VecInit((0 until StoreQueueSize).map(j => addrvalid(j) && allocated(j))))
555    // vector store will consider all inactive || secondInvalid flows as valid
556    val addrValidVec = WireInit(VecInit((0 until StoreQueueSize).map(j => addrvalid(j) && allocated(j))))
557    val dataValidVec = WireInit(VecInit((0 until StoreQueueSize).map(j => datavalid(j))))
558    val allValidVec  = WireInit(VecInit((0 until StoreQueueSize).map(j => addrvalid(j) && datavalid(j) && allocated(j))))
559
560    val lfstEnable = Constantin.createRecord("LFSTEnable", LFSTEnable)
561    val storeSetHitVec = Mux(lfstEnable,
562      WireInit(VecInit((0 until StoreQueueSize).map(j => io.forward(i).uop.loadWaitBit && uop(j).robIdx === io.forward(i).uop.waitForRobIdx))),
563      WireInit(VecInit((0 until StoreQueueSize).map(j => uop(j).storeSetHit && uop(j).ssid === io.forward(i).uop.ssid)))
564    )
565
566    val forwardMask1 = Mux(differentFlag, ~deqMask, deqMask ^ forwardMask)
567    val forwardMask2 = Mux(differentFlag, forwardMask, 0.U(StoreQueueSize.W))
568    val canForward1 = forwardMask1 & allValidVec.asUInt
569    val canForward2 = forwardMask2 & allValidVec.asUInt
570    val needForward = Mux(differentFlag, ~deqMask | forwardMask, deqMask ^ forwardMask)
571
572    XSDebug(p"$i f1 ${Binary(canForward1)} f2 ${Binary(canForward2)} " +
573      p"sqIdx ${io.forward(i).sqIdx} pa ${Hexadecimal(io.forward(i).paddr)}\n"
574    )
575
576    // do real fwd query (cam lookup in load_s1)
577    dataModule.io.needForward(i)(0) := canForward1 & vaddrModule.io.forwardMmask(i).asUInt
578    dataModule.io.needForward(i)(1) := canForward2 & vaddrModule.io.forwardMmask(i).asUInt
579
580    vaddrModule.io.forwardMdata(i) := io.forward(i).vaddr
581    vaddrModule.io.forwardDataMask(i) := io.forward(i).mask
582    paddrModule.io.forwardMdata(i) := io.forward(i).paddr
583    paddrModule.io.forwardDataMask(i) := io.forward(i).mask
584
585    // vaddr cam result does not equal to paddr cam result
586    // replay needed
587    // val vpmaskNotEqual = ((paddrModule.io.forwardMmask(i).asUInt ^ vaddrModule.io.forwardMmask(i).asUInt) & needForward) =/= 0.U
588    // val vaddrMatchFailed = vpmaskNotEqual && io.forward(i).valid
589    val vpmaskNotEqual = (
590      (RegNext(paddrModule.io.forwardMmask(i).asUInt) ^ RegNext(vaddrModule.io.forwardMmask(i).asUInt)) &
591      RegNext(needForward) &
592      RegNext(addrRealValidVec.asUInt)
593    ) =/= 0.U
594    val vaddrMatchFailed = vpmaskNotEqual && RegNext(io.forward(i).valid)
595    when (vaddrMatchFailed) {
596      XSInfo("vaddrMatchFailed: pc %x pmask %x vmask %x\n",
597        RegNext(io.forward(i).uop.pc),
598        RegNext(needForward & paddrModule.io.forwardMmask(i).asUInt),
599        RegNext(needForward & vaddrModule.io.forwardMmask(i).asUInt)
600      );
601    }
602    XSPerfAccumulate("vaddr_match_failed", vpmaskNotEqual)
603    XSPerfAccumulate("vaddr_match_really_failed", vaddrMatchFailed)
604
605    // Fast forward mask will be generated immediately (load_s1)
606    io.forward(i).forwardMaskFast := dataModule.io.forwardMaskFast(i)
607
608    // Forward result will be generated 1 cycle later (load_s2)
609    io.forward(i).forwardMask := dataModule.io.forwardMask(i)
610    io.forward(i).forwardData := dataModule.io.forwardData(i)
611    // If addr match, data not ready, mark it as dataInvalid
612    // load_s1: generate dataInvalid in load_s1 to set fastUop
613    val dataInvalidMask1 = (addrValidVec.asUInt & ~dataValidVec.asUInt & vaddrModule.io.forwardMmask(i).asUInt & forwardMask1.asUInt)
614    val dataInvalidMask2 = (addrValidVec.asUInt & ~dataValidVec.asUInt & vaddrModule.io.forwardMmask(i).asUInt & forwardMask2.asUInt)
615    val dataInvalidMask = dataInvalidMask1 | dataInvalidMask2
616    io.forward(i).dataInvalidFast := dataInvalidMask.orR
617
618    // make chisel happy
619    val dataInvalidMask1Reg = Wire(UInt(StoreQueueSize.W))
620    dataInvalidMask1Reg := RegNext(dataInvalidMask1)
621    // make chisel happy
622    val dataInvalidMask2Reg = Wire(UInt(StoreQueueSize.W))
623    dataInvalidMask2Reg := RegNext(dataInvalidMask2)
624    val dataInvalidMaskReg = dataInvalidMask1Reg | dataInvalidMask2Reg
625
626    // If SSID match, address not ready, mark it as addrInvalid
627    // load_s2: generate addrInvalid
628    val addrInvalidMask1 = (~addrValidVec.asUInt & storeSetHitVec.asUInt & forwardMask1.asUInt)
629    val addrInvalidMask2 = (~addrValidVec.asUInt & storeSetHitVec.asUInt & forwardMask2.asUInt)
630    // make chisel happy
631    val addrInvalidMask1Reg = Wire(UInt(StoreQueueSize.W))
632    addrInvalidMask1Reg := RegNext(addrInvalidMask1)
633    // make chisel happy
634    val addrInvalidMask2Reg = Wire(UInt(StoreQueueSize.W))
635    addrInvalidMask2Reg := RegNext(addrInvalidMask2)
636    val addrInvalidMaskReg = addrInvalidMask1Reg | addrInvalidMask2Reg
637
638    // load_s2
639    io.forward(i).dataInvalid := RegNext(io.forward(i).dataInvalidFast)
640    // check if vaddr forward mismatched
641    io.forward(i).matchInvalid := vaddrMatchFailed
642
643    // data invalid sq index
644    // check whether false fail
645    // check flag
646    val s2_differentFlag = RegNext(differentFlag)
647    val s2_enqPtrExt = RegNext(enqPtrExt(0))
648    val s2_deqPtrExt = RegNext(deqPtrExt(0))
649
650    // addr invalid sq index
651    // make chisel happy
652    val addrInvalidMaskRegWire = Wire(UInt(StoreQueueSize.W))
653    addrInvalidMaskRegWire := addrInvalidMaskReg
654    val addrInvalidFlag = addrInvalidMaskRegWire.orR
655    val hasInvalidAddr = (~addrValidVec.asUInt & needForward).orR
656
657    val addrInvalidSqIdx1 = OHToUInt(Reverse(PriorityEncoderOH(Reverse(addrInvalidMask1Reg))))
658    val addrInvalidSqIdx2 = OHToUInt(Reverse(PriorityEncoderOH(Reverse(addrInvalidMask2Reg))))
659    val addrInvalidSqIdx = Mux(addrInvalidMask2Reg.orR, addrInvalidSqIdx2, addrInvalidSqIdx1)
660
661    // store-set content management
662    //                +-----------------------+
663    //                | Search a SSID for the |
664    //                |    load operation     |
665    //                +-----------------------+
666    //                           |
667    //                           V
668    //                 +-------------------+
669    //                 | load wait strict? |
670    //                 +-------------------+
671    //                           |
672    //                           V
673    //               +----------------------+
674    //            Set|                      |Clean
675    //               V                      V
676    //  +------------------------+   +------------------------------+
677    //  | Waiting for all older  |   | Wait until the corresponding |
678    //  |   stores operations    |   | older store operations       |
679    //  +------------------------+   +------------------------------+
680
681
682
683    when (RegNext(io.forward(i).uop.loadWaitStrict)) {
684      io.forward(i).addrInvalidSqIdx := RegNext(io.forward(i).uop.sqIdx - 1.U)
685    } .elsewhen (addrInvalidFlag) {
686      io.forward(i).addrInvalidSqIdx.flag := Mux(!s2_differentFlag || addrInvalidSqIdx >= s2_deqPtrExt.value, s2_deqPtrExt.flag, s2_enqPtrExt.flag)
687      io.forward(i).addrInvalidSqIdx.value := addrInvalidSqIdx
688    } .otherwise {
689      // may be store inst has been written to sbuffer already.
690      io.forward(i).addrInvalidSqIdx := RegNext(io.forward(i).uop.sqIdx)
691    }
692    io.forward(i).addrInvalid := Mux(RegNext(io.forward(i).uop.loadWaitStrict), RegNext(hasInvalidAddr), addrInvalidFlag)
693
694    // data invalid sq index
695    // make chisel happy
696    val dataInvalidMaskRegWire = Wire(UInt(StoreQueueSize.W))
697    dataInvalidMaskRegWire := dataInvalidMaskReg
698    val dataInvalidFlag = dataInvalidMaskRegWire.orR
699
700    val dataInvalidSqIdx1 = OHToUInt(Reverse(PriorityEncoderOH(Reverse(dataInvalidMask1Reg))))
701    val dataInvalidSqIdx2 = OHToUInt(Reverse(PriorityEncoderOH(Reverse(dataInvalidMask2Reg))))
702    val dataInvalidSqIdx = Mux(dataInvalidMask2Reg.orR, dataInvalidSqIdx2, dataInvalidSqIdx1)
703
704    when (dataInvalidFlag) {
705      io.forward(i).dataInvalidSqIdx.flag := Mux(!s2_differentFlag || dataInvalidSqIdx >= s2_deqPtrExt.value, s2_deqPtrExt.flag, s2_enqPtrExt.flag)
706      io.forward(i).dataInvalidSqIdx.value := dataInvalidSqIdx
707    } .otherwise {
708      // may be store inst has been written to sbuffer already.
709      io.forward(i).dataInvalidSqIdx := RegNext(io.forward(i).uop.sqIdx)
710    }
711  }
712
713  /**
714    * Memory mapped IO / other uncached operations
715    *
716    * States:
717    * (1) writeback from store units: mark as pending
718    * (2) when they reach ROB's head, they can be sent to uncache channel
719    * (3) response from uncache channel: mark as datavalidmask.wen
720    * (4) writeback to ROB (and other units): mark as writebacked
721    * (5) ROB commits the instruction: same as normal instructions
722    */
723  //(2) when they reach ROB's head, they can be sent to uncache channel
724  // TODO: CAN NOT deal with vector mmio now!
725  val s_idle :: s_req :: s_resp :: s_wb :: s_wait :: Nil = Enum(5)
726  val uncacheState = RegInit(s_idle)
727  switch(uncacheState) {
728    is(s_idle) {
729      when(RegNext(io.rob.pendingst && pending(deqPtr) && allocated(deqPtr) && datavalid(deqPtr) && addrvalid(deqPtr))) {
730        uncacheState := s_req
731      }
732    }
733    is(s_req) {
734      when (io.uncache.req.fire) {
735        when (io.uncacheOutstanding) {
736          uncacheState := s_wb
737        } .otherwise {
738          uncacheState := s_resp
739        }
740      }
741    }
742    is(s_resp) {
743      when(io.uncache.resp.fire) {
744        uncacheState := s_wb
745      }
746    }
747    is(s_wb) {
748      when (io.mmioStout.fire || io.vecmmioStout.fire) {
749        uncacheState := s_wait
750      }
751    }
752    is(s_wait) {
753      // A MMIO store can always move cmtPtrExt as it must be ROB head
754      when(scommit > 0.U) {
755        uncacheState := s_idle // ready for next mmio
756      }
757    }
758  }
759  io.uncache.req.valid := uncacheState === s_req
760
761  io.uncache.req.bits := DontCare
762  io.uncache.req.bits.cmd  := MemoryOpConstants.M_XWR
763  io.uncache.req.bits.addr := paddrModule.io.rdata(0) // data(deqPtr) -> rdata(0)
764  io.uncache.req.bits.data := shiftDataToLow(paddrModule.io.rdata(0), dataModule.io.rdata(0).data)
765  io.uncache.req.bits.mask := shiftMaskToLow(paddrModule.io.rdata(0), dataModule.io.rdata(0).mask)
766
767  // CBO op type check can be delayed for 1 cycle,
768  // as uncache op will not start in s_idle
769  val cbo_mmio_addr = paddrModule.io.rdata(0) >> 2 << 2 // clear lowest 2 bits for op
770  val cbo_mmio_op = 0.U //TODO
771  val cbo_mmio_data = cbo_mmio_addr | cbo_mmio_op
772  when(RegNext(LSUOpType.isCbo(uop(deqPtr).fuOpType))){
773    io.uncache.req.bits.addr := DontCare // TODO
774    io.uncache.req.bits.data := paddrModule.io.rdata(0)
775    io.uncache.req.bits.mask := DontCare // TODO
776  }
777
778  io.uncache.req.bits.atomic := atomic(RegNext(rdataPtrExtNext(0)).value)
779
780  when(io.uncache.req.fire){
781    // mmio store should not be committed until uncache req is sent
782    pending(deqPtr) := false.B
783
784    XSDebug(
785      p"uncache req: pc ${Hexadecimal(uop(deqPtr).pc)} " +
786      p"addr ${Hexadecimal(io.uncache.req.bits.addr)} " +
787      p"data ${Hexadecimal(io.uncache.req.bits.data)} " +
788      p"op ${Hexadecimal(io.uncache.req.bits.cmd)} " +
789      p"mask ${Hexadecimal(io.uncache.req.bits.mask)}\n"
790    )
791  }
792
793  // (3) response from uncache channel: mark as datavalid
794  io.uncache.resp.ready := true.B
795
796  // (4) scalar store: writeback to ROB (and other units): mark as writebacked
797  io.mmioStout.valid := uncacheState === s_wb && !isVec(deqPtr)
798  io.mmioStout.bits.uop := uop(deqPtr)
799  io.mmioStout.bits.uop.sqIdx := deqPtrExt(0)
800  io.mmioStout.bits.data := shiftDataToLow(paddrModule.io.rdata(0), dataModule.io.rdata(0).data) // dataModule.io.rdata.read(deqPtr)
801  io.mmioStout.bits.debug.isMMIO := true.B
802  io.mmioStout.bits.debug.paddr := DontCare
803  io.mmioStout.bits.debug.isPerfCnt := false.B
804  io.mmioStout.bits.debug.vaddr := DontCare
805  // Remove MMIO inst from store queue after MMIO request is being sent
806  // That inst will be traced by uncache state machine
807  when (io.mmioStout.fire) {
808    allocated(deqPtr) := false.B
809  }
810
811  // (4) or vector store:
812  // TODO: implement it!
813  io.vecmmioStout := DontCare
814  io.vecmmioStout.valid := uncacheState === s_wb && isVec(deqPtr)
815  io.vecmmioStout.bits.uop := uop(deqPtr)
816  io.vecmmioStout.bits.uop.sqIdx := deqPtrExt(0)
817  io.vecmmioStout.bits.data := shiftDataToLow(paddrModule.io.rdata(0), dataModule.io.rdata(0).data) // dataModule.io.rdata.read(deqPtr)
818  io.vecmmioStout.bits.debug.isMMIO := true.B
819  io.vecmmioStout.bits.debug.paddr := DontCare
820  io.vecmmioStout.bits.debug.isPerfCnt := false.B
821  io.vecmmioStout.bits.debug.vaddr := DontCare
822  // Remove MMIO inst from store queue after MMIO request is being sent
823  // That inst will be traced by uncache state machine
824  when (io.vecmmioStout.fire) {
825    allocated(deqPtr) := false.B
826  }
827
828  /**
829    * ROB commits store instructions (mark them as committed)
830    *
831    * (1) When store commits, mark it as committed.
832    * (2) They will not be cancelled and can be sent to lower level.
833    */
834  XSError(uncacheState =/= s_idle && uncacheState =/= s_wait && commitCount > 0.U,
835   "should not commit instruction when MMIO has not been finished\n")
836
837  val scalarcommitVec = WireInit(VecInit(Seq.fill(CommitWidth)(false.B)))
838  val veccommitVec = WireInit(VecInit(Seq.fill(CommitWidth)(false.B)))
839  // TODO: Deal with vector store mmio
840  for (i <- 0 until CommitWidth) {
841    val veccount = PopCount(veccommitVec.take(i))
842    when (allocated(cmtPtrExt(i).value) && isVec(cmtPtrExt(i).value) && isNotAfter(uop(cmtPtrExt(i).value).robIdx, io.rob.pendingPtr) && vecMbCommit(cmtPtrExt(i).value)) {
843      if (i == 0){
844        // TODO: fixme for vector mmio
845        when ((uncacheState === s_idle) || (uncacheState === s_wait && scommit > 0.U)){
846          committed(cmtPtrExt(0).value) := true.B
847          veccommitVec(i) := true.B
848        }
849      } else {
850        committed(cmtPtrExt(i).value) := true.B
851        veccommitVec(i) := veccommitVec(i - 1) || scalarcommitVec(i - 1)
852      }
853    } .elsewhen (scalarCommitCount > i.U - veccount) {
854      if (i == 0){
855        when ((uncacheState === s_idle) || (uncacheState === s_wait && scommit > 0.U)){
856          committed(cmtPtrExt(0).value) := true.B
857          scalarcommitVec(i) := true.B
858        }
859      } else {
860        committed(cmtPtrExt(i).value) := true.B
861        scalarcommitVec(i) := veccommitVec(i - 1) || scalarcommitVec(i - 1)
862      }
863    }
864  }
865
866  scalarCommitted := PopCount(scalarcommitVec)
867  vecCommitted := PopCount(veccommitVec)
868  commitCount := scalarCommitted + vecCommitted
869
870  cmtPtrExt := cmtPtrExt.map(_ + commitCount)
871
872  // committed stores will not be cancelled and can be sent to lower level.
873  // remove retired insts from sq, add retired store to sbuffer
874
875  // Read data from data module
876  // As store queue grows larger and larger, time needed to read data from data
877  // module keeps growing higher. Now we give data read a whole cycle.
878  val mmioStall = mmio(rdataPtrExt(0).value)
879  for (i <- 0 until EnsbufferWidth) {
880    val ptr = rdataPtrExt(i).value
881    dataBuffer.io.enq(i).valid := allocated(ptr) && committed(ptr) && (!isVec(ptr) || vecMbCommit(ptr)) && !mmioStall
882    // Note that store data/addr should both be valid after store's commit
883    assert(!dataBuffer.io.enq(i).valid || allvalid(ptr) || (allocated(ptr) && vecMbCommit(ptr)))
884    dataBuffer.io.enq(i).bits.addr     := paddrModule.io.rdata(i)
885    dataBuffer.io.enq(i).bits.vaddr    := vaddrModule.io.rdata(i)
886    dataBuffer.io.enq(i).bits.data     := dataModule.io.rdata(i).data
887    dataBuffer.io.enq(i).bits.mask     := dataModule.io.rdata(i).mask
888    dataBuffer.io.enq(i).bits.wline    := paddrModule.io.rlineflag(i)
889    dataBuffer.io.enq(i).bits.sqPtr    := rdataPtrExt(i)
890    dataBuffer.io.enq(i).bits.prefetch := prefetch(ptr)
891    dataBuffer.io.enq(i).bits.vecValid := !isVec(ptr) || vecDataValid(ptr) // scalar is always valid
892  }
893
894  // Send data stored in sbufferReqBitsReg to sbuffer
895  for (i <- 0 until EnsbufferWidth) {
896    io.sbuffer(i).valid := dataBuffer.io.deq(i).valid
897    dataBuffer.io.deq(i).ready := io.sbuffer(i).ready
898    // Write line request should have all 1 mask
899    assert(!(io.sbuffer(i).valid && io.sbuffer(i).bits.wline && io.sbuffer(i).bits.vecValid && !io.sbuffer(i).bits.mask.andR))
900    io.sbuffer(i).bits := DontCare
901    io.sbuffer(i).bits.cmd   := MemoryOpConstants.M_XWR
902    io.sbuffer(i).bits.addr  := dataBuffer.io.deq(i).bits.addr
903    io.sbuffer(i).bits.vaddr := dataBuffer.io.deq(i).bits.vaddr
904    io.sbuffer(i).bits.data  := dataBuffer.io.deq(i).bits.data
905    io.sbuffer(i).bits.mask  := dataBuffer.io.deq(i).bits.mask
906    io.sbuffer(i).bits.wline := dataBuffer.io.deq(i).bits.wline
907    io.sbuffer(i).bits.prefetch := dataBuffer.io.deq(i).bits.prefetch
908    io.sbuffer(i).bits.vecValid := dataBuffer.io.deq(i).bits.vecValid
909    // io.sbuffer(i).fire is RegNexted, as sbuffer data write takes 2 cycles.
910    // Before data write finish, sbuffer is unable to provide store to load
911    // forward data. As an workaround, deqPtrExt and allocated flag update
912    // is delayed so that load can get the right data from store queue.
913    val ptr = dataBuffer.io.deq(i).bits.sqPtr.value
914    when (RegNext(io.sbuffer(i).fire)) {
915      allocated(RegEnable(ptr, io.sbuffer(i).fire)) := false.B
916      XSDebug("sbuffer "+i+" fire: ptr %d\n", ptr)
917    }
918  }
919
920  // Consistent with the logic above, only the vectore difftest required signal is separated from the rtl code
921  if (env.EnableDifftest) {
922    for (i <- 0 until EnsbufferWidth) {
923      val ptr = rdataPtrExt(i).value
924      difftestBuffer.get.io.enq(i).valid := allocated(ptr) && committed(ptr) && (!isVec(ptr) || vecMbCommit(ptr)) && !mmioStall
925      difftestBuffer.get.io.enq(i).bits := uop(ptr)
926    }
927    for (i <- 0 until EnsbufferWidth) {
928      io.sbufferVecDifftestInfo(i).valid := difftestBuffer.get.io.deq(i).valid
929      difftestBuffer.get.io.deq(i).ready := io.sbufferVecDifftestInfo(i).ready
930
931      io.sbufferVecDifftestInfo(i).bits := difftestBuffer.get.io.deq(i).bits
932    }
933  }
934
935  (1 until EnsbufferWidth).foreach(i => when(io.sbuffer(i).fire) { assert(io.sbuffer(i - 1).fire) })
936  if (coreParams.dcacheParametersOpt.isEmpty) {
937    for (i <- 0 until EnsbufferWidth) {
938      val ptr = deqPtrExt(i).value
939      val ram = DifftestMem(64L * 1024 * 1024 * 1024, 8)
940      val wen = allocated(ptr) && committed(ptr) && !mmio(ptr)
941      val waddr = ((paddrModule.io.rdata(i) - "h80000000".U) >> 3).asUInt
942      val wdata = Mux(paddrModule.io.rdata(i)(3), dataModule.io.rdata(i).data(127, 64), dataModule.io.rdata(i).data(63, 0))
943      val wmask = Mux(paddrModule.io.rdata(i)(3), dataModule.io.rdata(i).mask(15, 8), dataModule.io.rdata(i).mask(7, 0))
944      when (wen) {
945        ram.write(waddr, wdata.asTypeOf(Vec(8, UInt(8.W))), wmask.asBools)
946      }
947    }
948  }
949
950  // Read vaddr for mem exception
951  io.exceptionAddr.vaddr  := exceptionBuffer.io.exceptionAddr.vaddr
952  io.exceptionAddr.gpaddr  := exceptionBuffer.io.exceptionAddr.gpaddr
953  io.exceptionAddr.vstart := exceptionBuffer.io.exceptionAddr.vstart
954  io.exceptionAddr.vl     := exceptionBuffer.io.exceptionAddr.vl
955
956  // vector commit or replay from
957  val vecCommittmp = Wire(Vec(StoreQueueSize, Vec(VecStorePipelineWidth, Bool())))
958  val vecCommit = Wire(Vec(StoreQueueSize, Bool()))
959  for (i <- 0 until StoreQueueSize) {
960    val fbk = io.vecFeedback
961    for (j <- 0 until VecStorePipelineWidth) {
962      vecCommittmp(i)(j) := fbk(j).valid && fbk(j).bits.isCommit && uop(i).robIdx === fbk(j).bits.robidx && uop(i).uopIdx === fbk(j).bits.uopidx
963    }
964    vecCommit(i) := vecCommittmp(i).reduce(_ || _)
965
966    when (vecCommit(i)) {
967      vecMbCommit(i) := true.B
968    }
969  }
970
971  // misprediction recovery / exception redirect
972  // invalidate sq term using robIdx
973  val needCancel = Wire(Vec(StoreQueueSize, Bool()))
974  for (i <- 0 until StoreQueueSize) {
975    needCancel(i) := uop(i).robIdx.needFlush(io.brqRedirect) && allocated(i) && !committed(i)
976    when (needCancel(i)) {
977      allocated(i) := false.B
978    }
979  }
980
981 /**
982* update pointers
983**/
984  val enqCancelValid = canEnqueue.zip(io.enq.req).map{case (v , x) =>
985    v && x.bits.robIdx.needFlush(io.brqRedirect)
986  }
987  val enqCancelNum = enqCancelValid.zip(io.enq.req).map{case (v, req) =>
988    Mux(v, req.bits.numLsElem, 0.U)
989  }
990  val lastEnqCancel = RegNext(enqCancelNum.reduce(_ + _)) // 1 cycle after redirect
991
992  val lastCycleCancelCount = PopCount(RegNext(needCancel)) // 1 cycle after redirect
993  val lastCycleRedirect = RegNext(io.brqRedirect.valid) // 1 cycle after redirect
994  val enqNumber = validVStoreFlow.reduce(_ + _)
995
996  val lastlastCycleRedirect=RegNext(lastCycleRedirect)// 2 cycle after redirect
997  val redirectCancelCount = RegEnable(lastCycleCancelCount + lastEnqCancel, lastCycleRedirect) // 2 cycle after redirect
998
999  when (lastlastCycleRedirect) {
1000    // we recover the pointers in 2 cycle after redirect for better timing
1001    enqPtrExt := VecInit(enqPtrExt.map(_ - redirectCancelCount))
1002  }.otherwise {
1003    // lastCycleRedirect.valid or nornal case
1004    // when lastCycleRedirect.valid, enqNumber === 0.U, enqPtrExt will not change
1005    enqPtrExt := VecInit(enqPtrExt.map(_ + enqNumber))
1006  }
1007  assert(!(lastCycleRedirect && enqNumber =/= 0.U))
1008
1009  deqPtrExt := deqPtrExtNext
1010  rdataPtrExt := rdataPtrExtNext
1011
1012  // val dequeueCount = Mux(io.sbuffer(1).fire, 2.U, Mux(io.sbuffer(0).fire || io.mmioStout.fire, 1.U, 0.U))
1013
1014  // If redirect at T0, sqCancelCnt is at T2
1015  io.sqCancelCnt := redirectCancelCount
1016  val ForceWriteUpper = Wire(UInt(log2Up(StoreQueueSize + 1).W))
1017  ForceWriteUpper := Constantin.createRecord(s"ForceWriteUpper_${p(XSCoreParamsKey).HartId}", initValue = 60)
1018  val ForceWriteLower = Wire(UInt(log2Up(StoreQueueSize + 1).W))
1019  ForceWriteLower := Constantin.createRecord(s"ForceWriteLower_${p(XSCoreParamsKey).HartId}", initValue = 55)
1020
1021  val valid_cnt = PopCount(allocated)
1022  io.force_write := RegNext(Mux(valid_cnt >= ForceWriteUpper, true.B, valid_cnt >= ForceWriteLower && io.force_write), init = false.B)
1023
1024  // io.sqempty will be used by sbuffer
1025  // We delay it for 1 cycle for better timing
1026  // When sbuffer need to check if it is empty, the pipeline is blocked, which means delay io.sqempty
1027  // for 1 cycle will also promise that sq is empty in that cycle
1028  io.sqEmpty := RegNext(
1029    enqPtrExt(0).value === deqPtrExt(0).value &&
1030    enqPtrExt(0).flag === deqPtrExt(0).flag
1031  )
1032  // perf counter
1033  QueuePerf(StoreQueueSize, validCount, !allowEnqueue)
1034  val vecValidVec = WireInit(VecInit((0 until StoreQueueSize).map(i => allocated(i) && isVec(i))))
1035  QueuePerf(StoreQueueSize, PopCount(vecValidVec), !allowEnqueue)
1036  io.sqFull := !allowEnqueue
1037  XSPerfAccumulate("mmioCycle", uncacheState =/= s_idle) // lq is busy dealing with uncache req
1038  XSPerfAccumulate("mmioCnt", io.uncache.req.fire)
1039  XSPerfAccumulate("mmio_wb_success", io.mmioStout.fire || io.vecmmioStout.fire)
1040  XSPerfAccumulate("mmio_wb_blocked", (io.mmioStout.valid && !io.mmioStout.ready) || (io.vecmmioStout.valid && !io.vecmmioStout.ready))
1041  XSPerfAccumulate("validEntryCnt", distanceBetween(enqPtrExt(0), deqPtrExt(0)))
1042  XSPerfAccumulate("cmtEntryCnt", distanceBetween(cmtPtrExt(0), deqPtrExt(0)))
1043  XSPerfAccumulate("nCmtEntryCnt", distanceBetween(enqPtrExt(0), cmtPtrExt(0)))
1044
1045  val perfValidCount = distanceBetween(enqPtrExt(0), deqPtrExt(0))
1046  val perfEvents = Seq(
1047    ("mmioCycle      ", uncacheState =/= s_idle),
1048    ("mmioCnt        ", io.uncache.req.fire),
1049    ("mmio_wb_success", io.mmioStout.fire || io.vecmmioStout.fire),
1050    ("mmio_wb_blocked", (io.mmioStout.valid && !io.mmioStout.ready) || (io.vecmmioStout.valid && !io.vecmmioStout.ready)),
1051    ("stq_1_4_valid  ", (perfValidCount < (StoreQueueSize.U/4.U))),
1052    ("stq_2_4_valid  ", (perfValidCount > (StoreQueueSize.U/4.U)) & (perfValidCount <= (StoreQueueSize.U/2.U))),
1053    ("stq_3_4_valid  ", (perfValidCount > (StoreQueueSize.U/2.U)) & (perfValidCount <= (StoreQueueSize.U*3.U/4.U))),
1054    ("stq_4_4_valid  ", (perfValidCount > (StoreQueueSize.U*3.U/4.U))),
1055  )
1056  generatePerfEvent()
1057
1058  // debug info
1059  XSDebug("enqPtrExt %d:%d deqPtrExt %d:%d\n", enqPtrExt(0).flag, enqPtr, deqPtrExt(0).flag, deqPtr)
1060
1061  def PrintFlag(flag: Bool, name: String): Unit = {
1062    when(flag) {
1063      XSDebug(false, true.B, name)
1064    }.otherwise {
1065      XSDebug(false, true.B, " ")
1066    }
1067  }
1068
1069  for (i <- 0 until StoreQueueSize) {
1070    XSDebug(i + ": pc %x va %x pa %x data %x ",
1071      uop(i).pc,
1072      debug_vaddr(i),
1073      debug_paddr(i),
1074      debug_data(i)
1075    )
1076    PrintFlag(allocated(i), "a")
1077    PrintFlag(allocated(i) && addrvalid(i), "a")
1078    PrintFlag(allocated(i) && datavalid(i), "d")
1079    PrintFlag(allocated(i) && committed(i), "c")
1080    PrintFlag(allocated(i) && pending(i), "p")
1081    PrintFlag(allocated(i) && mmio(i), "m")
1082    XSDebug(false, true.B, "\n")
1083  }
1084
1085}
1086