xref: /XiangShan/src/main/scala/xiangshan/mem/lsqueue/StoreQueue.scala (revision a9b27cdf68549200138a5cb5607beeb5b2cdff1b)
1/***************************************************************************************
2* Copyright (c) 2024 Beijing Institute of Open Source Chip (BOSC)
3* Copyright (c) 2020-2024 Institute of Computing Technology, Chinese Academy of Sciences
4* Copyright (c) 2020-2021 Peng Cheng Laboratory
5*
6* XiangShan is licensed under Mulan PSL v2.
7* You can use this software according to the terms and conditions of the Mulan PSL v2.
8* You may obtain a copy of Mulan PSL v2 at:
9*          http://license.coscl.org.cn/MulanPSL2
10*
11* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
12* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
13* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
14*
15* See the Mulan PSL v2 for more details.
16***************************************************************************************/
17
18package xiangshan.mem
19
20import chisel3._
21import chisel3.util._
22import difftest._
23import difftest.common.DifftestMem
24import org.chipsalliance.cde.config.Parameters
25import utility._
26import utils._
27import xiangshan._
28import xiangshan.cache._
29import xiangshan.cache.{DCacheLineIO, DCacheWordIO, MemoryOpConstants}
30import xiangshan.backend._
31import xiangshan.backend.rob.{RobLsqIO, RobPtr}
32import xiangshan.backend.Bundles.{DynInst, MemExuOutput}
33import xiangshan.backend.decode.isa.bitfield.{Riscv32BitInst, XSInstBitFields}
34import xiangshan.backend.fu.FuConfig._
35import xiangshan.backend.fu.FuType
36import xiangshan.ExceptionNO._
37
38class SqPtr(implicit p: Parameters) extends CircularQueuePtr[SqPtr](
39  p => p(XSCoreParamsKey).StoreQueueSize
40){
41}
42
43object SqPtr {
44  def apply(f: Bool, v: UInt)(implicit p: Parameters): SqPtr = {
45    val ptr = Wire(new SqPtr)
46    ptr.flag := f
47    ptr.value := v
48    ptr
49  }
50}
51
52class SqEnqIO(implicit p: Parameters) extends MemBlockBundle {
53  val canAccept = Output(Bool())
54  val lqCanAccept = Input(Bool())
55  val needAlloc = Vec(LSQEnqWidth, Input(Bool()))
56  val req = Vec(LSQEnqWidth, Flipped(ValidIO(new DynInst)))
57  val resp = Vec(LSQEnqWidth, Output(new SqPtr))
58}
59
60class DataBufferEntry (implicit p: Parameters)  extends DCacheBundle {
61  val addr   = UInt(PAddrBits.W)
62  val vaddr  = UInt(VAddrBits.W)
63  val data   = UInt(VLEN.W)
64  val mask   = UInt((VLEN/8).W)
65  val wline = Bool()
66  val sqPtr  = new SqPtr
67  val prefetch = Bool()
68  val vecValid = Bool()
69}
70
71class StoreExceptionBuffer(implicit p: Parameters) extends XSModule with HasCircularQueuePtrHelper {
72  val io = IO(new Bundle() {
73    val redirect = Flipped(ValidIO(new Redirect))
74    val storeAddrIn = Vec(StorePipelineWidth * 2 + VecStorePipelineWidth, Flipped(ValidIO(new LsPipelineBundle())))
75    val exceptionAddr = new ExceptionAddrIO
76  })
77
78  val req_valid = RegInit(false.B)
79  val req = Reg(new LsPipelineBundle())
80
81  // enqueue
82  // S1:
83  val s1_req = VecInit(io.storeAddrIn.map(_.bits))
84  val s1_valid = VecInit(io.storeAddrIn.map(_.valid))
85
86  // S2: delay 1 cycle
87  val s2_req = RegNext(s1_req)
88  val s2_valid = (0 until StorePipelineWidth * 2 + VecStorePipelineWidth).map(i =>
89    RegNext(s1_valid(i)) &&
90      !s2_req(i).uop.robIdx.needFlush(RegNext(io.redirect)) &&
91      !s2_req(i).uop.robIdx.needFlush(io.redirect)
92  )
93  val s2_has_exception = s2_req.map(x => ExceptionNO.selectByFu(x.uop.exceptionVec, StaCfg).asUInt.orR)
94
95  val s2_enqueue = Wire(Vec(StorePipelineWidth * 2 + VecStorePipelineWidth, Bool()))
96  for (w <- 0 until StorePipelineWidth * 2 + VecStorePipelineWidth) {
97    s2_enqueue(w) := s2_valid(w) && s2_has_exception(w)
98  }
99
100  when (req_valid && req.uop.robIdx.needFlush(io.redirect)) {
101    req_valid := s2_enqueue.asUInt.orR
102  }.elsewhen (s2_enqueue.asUInt.orR) {
103    req_valid := req_valid || true.B
104  }
105
106  def selectOldest[T <: LsPipelineBundle](valid: Seq[Bool], bits: Seq[T]): (Seq[Bool], Seq[T]) = {
107    assert(valid.length == bits.length)
108    if (valid.length == 0 || valid.length == 1) {
109      (valid, bits)
110    } else if (valid.length == 2) {
111      val res = Seq.fill(2)(Wire(Valid(chiselTypeOf(bits(0)))))
112      for (i <- res.indices) {
113        res(i).valid := valid(i)
114        res(i).bits := bits(i)
115      }
116      val oldest = Mux(valid(0) && valid(1),
117        Mux(isAfter(bits(0).uop.robIdx, bits(1).uop.robIdx) ||
118          (isNotBefore(bits(0).uop.robIdx, bits(1).uop.robIdx) && bits(0).uop.uopIdx > bits(1).uop.uopIdx), res(1), res(0)),
119        Mux(valid(0) && !valid(1), res(0), res(1)))
120      (Seq(oldest.valid), Seq(oldest.bits))
121    } else {
122      val left = selectOldest(valid.take(valid.length / 2), bits.take(bits.length / 2))
123      val right = selectOldest(valid.takeRight(valid.length - (valid.length / 2)), bits.takeRight(bits.length - (bits.length / 2)))
124      selectOldest(left._1 ++ right._1, left._2 ++ right._2)
125    }
126  }
127
128  val reqSel = selectOldest(s2_enqueue, s2_req)
129
130  when (req_valid) {
131    req := Mux(
132      reqSel._1(0) && (isAfter(req.uop.robIdx, reqSel._2(0).uop.robIdx) || (isNotBefore(req.uop.robIdx, reqSel._2(0).uop.robIdx) && req.uop.uopIdx > reqSel._2(0).uop.uopIdx)),
133      reqSel._2(0),
134      req)
135  } .elsewhen (s2_enqueue.asUInt.orR) {
136    req := reqSel._2(0)
137  }
138
139  io.exceptionAddr.vaddr  := req.vaddr
140  io.exceptionAddr.gpaddr := req.gpaddr
141  io.exceptionAddr.vstart := req.uop.vpu.vstart
142  io.exceptionAddr.vl     := req.uop.vpu.vl
143}
144
145// Store Queue
146class StoreQueue(implicit p: Parameters) extends XSModule
147  with HasDCacheParameters
148  with HasCircularQueuePtrHelper
149  with HasPerfEvents
150  with HasVLSUParameters {
151  val io = IO(new Bundle() {
152    val hartId = Input(UInt(hartIdLen.W))
153    val enq = new SqEnqIO
154    val brqRedirect = Flipped(ValidIO(new Redirect))
155    val vecFeedback = Vec(VecLoadPipelineWidth, Flipped(ValidIO(new FeedbackToLsqIO)))
156    val storeAddrIn = Vec(StorePipelineWidth, Flipped(Valid(new LsPipelineBundle))) // store addr, data is not included
157    val storeAddrInRe = Vec(StorePipelineWidth, Input(new LsPipelineBundle())) // store more mmio and exception
158    val storeDataIn = Vec(StorePipelineWidth, Flipped(Valid(new MemExuOutput(isVector = true)))) // store data, send to sq from rs
159    val storeMaskIn = Vec(StorePipelineWidth, Flipped(Valid(new StoreMaskBundle))) // store mask, send to sq from rs
160    val sbuffer = Vec(EnsbufferWidth, Decoupled(new DCacheWordReqWithVaddrAndPfFlag)) // write committed store to sbuffer
161    val sbufferVecDifftestInfo = Vec(EnsbufferWidth, Decoupled(new DynInst)) // The vector store difftest needs is, write committed store to sbuffer
162    val uncacheOutstanding = Input(Bool())
163    val mmioStout = DecoupledIO(new MemExuOutput) // writeback uncached store
164    val vecmmioStout = DecoupledIO(new MemExuOutput(isVector = true))
165    val forward = Vec(LoadPipelineWidth, Flipped(new PipeLoadForwardQueryIO))
166    // TODO: scommit is only for scalar store
167    val rob = Flipped(new RobLsqIO)
168    val uncache = new UncacheWordIO
169    // val refill = Flipped(Valid(new DCacheLineReq ))
170    val exceptionAddr = new ExceptionAddrIO
171    val sqEmpty = Output(Bool())
172    val stAddrReadySqPtr = Output(new SqPtr)
173    val stAddrReadyVec = Output(Vec(StoreQueueSize, Bool()))
174    val stDataReadySqPtr = Output(new SqPtr)
175    val stDataReadyVec = Output(Vec(StoreQueueSize, Bool()))
176    val stIssuePtr = Output(new SqPtr)
177    val sqDeqPtr = Output(new SqPtr)
178    val sqFull = Output(Bool())
179    val sqCancelCnt = Output(UInt(log2Up(StoreQueueSize + 1).W))
180    val sqDeq = Output(UInt(log2Ceil(EnsbufferWidth + 1).W))
181    val force_write = Output(Bool())
182  })
183
184  println("StoreQueue: size:" + StoreQueueSize)
185
186  // data modules
187  val uop = Reg(Vec(StoreQueueSize, new DynInst))
188  // val data = Reg(Vec(StoreQueueSize, new LsqEntry))
189  val dataModule = Module(new SQDataModule(
190    numEntries = StoreQueueSize,
191    numRead = EnsbufferWidth,
192    numWrite = StorePipelineWidth,
193    numForward = LoadPipelineWidth
194  ))
195  dataModule.io := DontCare
196  val paddrModule = Module(new SQAddrModule(
197    dataWidth = PAddrBits,
198    numEntries = StoreQueueSize,
199    numRead = EnsbufferWidth,
200    numWrite = StorePipelineWidth,
201    numForward = LoadPipelineWidth
202  ))
203  paddrModule.io := DontCare
204  val vaddrModule = Module(new SQAddrModule(
205    dataWidth = VAddrBits,
206    numEntries = StoreQueueSize,
207    numRead = EnsbufferWidth, // sbuffer; badvaddr will be sent from exceptionBuffer
208    numWrite = StorePipelineWidth,
209    numForward = LoadPipelineWidth
210  ))
211  vaddrModule.io := DontCare
212  val dataBuffer = Module(new DatamoduleResultBuffer(new DataBufferEntry))
213  val difftestBuffer = if (env.EnableDifftest) Some(Module(new DatamoduleResultBuffer(new DynInst))) else None
214  val exceptionBuffer = Module(new StoreExceptionBuffer)
215  exceptionBuffer.io.redirect := io.brqRedirect
216  exceptionBuffer.io.exceptionAddr.isStore := DontCare
217  // vlsu exception!
218  for (i <- 0 until VecStorePipelineWidth) {
219    exceptionBuffer.io.storeAddrIn(StorePipelineWidth * 2 + i).valid               := io.vecFeedback(i).valid && io.vecFeedback(i).bits.feedback(VecFeedbacks.FLUSH) // have exception
220    exceptionBuffer.io.storeAddrIn(StorePipelineWidth * 2 + i).bits                := DontCare
221    exceptionBuffer.io.storeAddrIn(StorePipelineWidth * 2 + i).bits.vaddr          := io.vecFeedback(i).bits.vaddr
222    exceptionBuffer.io.storeAddrIn(StorePipelineWidth * 2 + i).bits.uop.uopIdx     := io.vecFeedback(i).bits.uopidx
223    exceptionBuffer.io.storeAddrIn(StorePipelineWidth * 2 + i).bits.uop.robIdx     := io.vecFeedback(i).bits.robidx
224    exceptionBuffer.io.storeAddrIn(StorePipelineWidth * 2 + i).bits.uop.vpu.vstart := io.vecFeedback(i).bits.vstart
225    exceptionBuffer.io.storeAddrIn(StorePipelineWidth * 2 + i).bits.uop.vpu.vl     := io.vecFeedback(i).bits.vl
226    exceptionBuffer.io.storeAddrIn(StorePipelineWidth * 2 + i).bits.uop.exceptionVec     := io.vecFeedback(i).bits.exceptionVec
227  }
228
229
230  val debug_paddr = Reg(Vec(StoreQueueSize, UInt((PAddrBits).W)))
231  val debug_vaddr = Reg(Vec(StoreQueueSize, UInt((VAddrBits).W)))
232  val debug_data = Reg(Vec(StoreQueueSize, UInt((XLEN).W)))
233
234  // state & misc
235  val allocated = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // sq entry has been allocated
236  val addrvalid = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // non-mmio addr is valid
237  val datavalid = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // non-mmio data is valid
238  val allvalid  = VecInit((0 until StoreQueueSize).map(i => addrvalid(i) && datavalid(i))) // non-mmio data & addr is valid
239  val committed = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // inst has been committed by rob
240  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
241  val mmio = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // mmio: inst is an mmio inst
242  val atomic = RegInit(VecInit(List.fill(StoreQueueSize)(false.B)))
243  val prefetch = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // need prefetch when committing this store to sbuffer?
244  val isVec = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // vector store instruction
245  //val vec_lastuop = Reg(Vec(StoreQueueSize, Bool())) // last uop of vector store instruction
246  val vecMbCommit = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // vector store committed from merge buffer to rob
247  val vecDataValid = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // vector store need write to sbuffer
248  val hasException = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // store has exception, should deq but not write sbuffer
249  val waitStoreS2 = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // wait for mmio and exception result until store_s2
250  // val vec_robCommit = Reg(Vec(StoreQueueSize, Bool())) // vector store committed by rob
251  // val vec_secondInv = RegInit(VecInit(List.fill(StoreQueueSize)(false.B))) // Vector unit-stride, second entry is invalid
252  val vecExceptionFlag = RegInit(0.U.asTypeOf(Valid(new DynInst)))
253
254  // ptr
255  val enqPtrExt = RegInit(VecInit((0 until io.enq.req.length).map(_.U.asTypeOf(new SqPtr))))
256  val rdataPtrExt = RegInit(VecInit((0 until EnsbufferWidth).map(_.U.asTypeOf(new SqPtr))))
257  val deqPtrExt = RegInit(VecInit((0 until EnsbufferWidth).map(_.U.asTypeOf(new SqPtr))))
258  val cmtPtrExt = RegInit(VecInit((0 until CommitWidth).map(_.U.asTypeOf(new SqPtr))))
259  val addrReadyPtrExt = RegInit(0.U.asTypeOf(new SqPtr))
260  val dataReadyPtrExt = RegInit(0.U.asTypeOf(new SqPtr))
261
262  val enqPtr = enqPtrExt(0).value
263  val deqPtr = deqPtrExt(0).value
264  val cmtPtr = cmtPtrExt(0).value
265
266  val validCount = distanceBetween(enqPtrExt(0), deqPtrExt(0))
267  val allowEnqueue = validCount <= (StoreQueueSize - LSQStEnqWidth).U
268
269  val deqMask = UIntToMask(deqPtr, StoreQueueSize)
270  val enqMask = UIntToMask(enqPtr, StoreQueueSize)
271
272  val commitCount = WireInit(0.U(log2Ceil(CommitWidth + 1).W))
273  val scommit = RegNext(io.rob.scommit)
274
275  // store can be committed by ROB
276  io.rob.mmio := DontCare
277  io.rob.uop := DontCare
278
279  // Read dataModule
280  assert(EnsbufferWidth <= 2)
281  // rdataPtrExtNext and rdataPtrExtNext+1 entry will be read from dataModule
282  val rdataPtrExtNext = WireInit(Mux(dataBuffer.io.enq(1).fire,
283    VecInit(rdataPtrExt.map(_ + 2.U)),
284    Mux(dataBuffer.io.enq(0).fire || io.mmioStout.fire || io.vecmmioStout.fire,
285      VecInit(rdataPtrExt.map(_ + 1.U)),
286      rdataPtrExt
287    )
288  ))
289
290  // deqPtrExtNext traces which inst is about to leave store queue
291  //
292  // io.sbuffer(i).fire is RegNexted, as sbuffer data write takes 2 cycles.
293  // Before data write finish, sbuffer is unable to provide store to load
294  // forward data. As an workaround, deqPtrExt and allocated flag update
295  // is delayed so that load can get the right data from store queue.
296  //
297  // Modify deqPtrExtNext and io.sqDeq with care!
298  val deqPtrExtNext = Mux(RegNext(io.sbuffer(1).fire),
299    VecInit(deqPtrExt.map(_ + 2.U)),
300    Mux((RegNext(io.sbuffer(0).fire)) || io.mmioStout.fire || io.vecmmioStout.fire,
301      VecInit(deqPtrExt.map(_ + 1.U)),
302      deqPtrExt
303    )
304  )
305  io.sqDeq := RegNext(Mux(RegNext(io.sbuffer(1).fire), 2.U,
306    Mux((RegNext(io.sbuffer(0).fire)) || io.mmioStout.fire || io.vecmmioStout.fire, 1.U, 0.U)
307  ))
308  assert(!RegNext(RegNext(io.sbuffer(0).fire) && (io.mmioStout.fire || io.vecmmioStout.fire)))
309
310  for (i <- 0 until EnsbufferWidth) {
311    dataModule.io.raddr(i) := rdataPtrExtNext(i).value
312    paddrModule.io.raddr(i) := rdataPtrExtNext(i).value
313    vaddrModule.io.raddr(i) := rdataPtrExtNext(i).value
314  }
315
316  /**
317    * Enqueue at dispatch
318    *
319    * Currently, StoreQueue only allows enqueue when #emptyEntries > EnqWidth
320    */
321  io.enq.canAccept := allowEnqueue
322  val canEnqueue = io.enq.req.map(_.valid)
323  val enqCancel = io.enq.req.map(_.bits.robIdx.needFlush(io.brqRedirect))
324  val vStoreFlow = io.enq.req.map(_.bits.numLsElem)
325  val validVStoreFlow = vStoreFlow.zipWithIndex.map{case (vLoadFlowNumItem, index) => Mux(!RegNext(io.brqRedirect.valid) && io.enq.canAccept && io.enq.lqCanAccept && canEnqueue(index), vLoadFlowNumItem, 0.U)}
326  val validVStoreOffset = vStoreFlow.zip(io.enq.needAlloc).map{case (flow, needAllocItem) => Mux(needAllocItem, flow, 0.U)}
327  val validVStoreOffsetRShift = 0.U +: validVStoreOffset.take(vStoreFlow.length - 1)
328
329  for (i <- 0 until io.enq.req.length) {
330    val sqIdx = enqPtrExt(0) + validVStoreOffsetRShift.take(i + 1).reduce(_ + _)
331    val index = io.enq.req(i).bits.sqIdx
332    val enqInstr = io.enq.req(i).bits.instr.asTypeOf(new XSInstBitFields)
333    when (canEnqueue(i) && !enqCancel(i)) {
334      // The maximum 'numLsElem' number that can be emitted per dispatch port is:
335      //    16 2 2 2 2 2.
336      // Therefore, VecMemLSQEnqIteratorNumberSeq = Seq(16, 2, 2, 2, 2, 2)
337      for (j <- 0 until VecMemLSQEnqIteratorNumberSeq(i)) {
338        when (j.U < validVStoreOffset(i)) {
339          uop((index + j.U).value) := io.enq.req(i).bits
340          // NOTE: the index will be used when replay
341          uop((index + j.U).value).sqIdx := sqIdx + j.U
342          allocated((index + j.U).value) := true.B
343          datavalid((index + j.U).value) := false.B
344          addrvalid((index + j.U).value) := false.B
345          committed((index + j.U).value) := false.B
346          pending((index + j.U).value) := false.B
347          prefetch((index + j.U).value) := false.B
348          mmio((index + j.U).value) := false.B
349          isVec((index + j.U).value) := enqInstr.isVecStore // check vector store by the encoding of inst
350          vecMbCommit((index + j.U).value) := false.B
351          vecDataValid((index + j.U).value) := false.B
352          hasException((index + j.U).value) := false.B
353          waitStoreS2((index + j.U).value) := true.B
354          XSError(!io.enq.canAccept || !io.enq.lqCanAccept, s"must accept $i\n")
355          XSError(index.value =/= sqIdx.value, s"must be the same entry $i\n")
356        }
357      }
358    }
359    io.enq.resp(i) := sqIdx
360  }
361  XSDebug(p"(ready, valid): ${io.enq.canAccept}, ${Binary(Cat(io.enq.req.map(_.valid)))}\n")
362
363  /**
364    * Update addr/dataReadyPtr when issue from rs
365    */
366  // update issuePtr
367  val IssuePtrMoveStride = 4
368  require(IssuePtrMoveStride >= 2)
369
370  val addrReadyLookupVec = (0 until IssuePtrMoveStride).map(addrReadyPtrExt + _.U)
371  val addrReadyLookup = addrReadyLookupVec.map(ptr => allocated(ptr.value) &&
372   (mmio(ptr.value) || addrvalid(ptr.value) || vecMbCommit(ptr.value))
373    && ptr =/= enqPtrExt(0))
374  val nextAddrReadyPtr = addrReadyPtrExt + PriorityEncoder(VecInit(addrReadyLookup.map(!_) :+ true.B))
375  addrReadyPtrExt := nextAddrReadyPtr
376
377  (0 until StoreQueueSize).map(i => {
378    io.stAddrReadyVec(i) := RegNext(allocated(i) && (mmio(i) || addrvalid(i) || (isVec(i) && vecMbCommit(i))))
379  })
380
381  when (io.brqRedirect.valid) {
382    addrReadyPtrExt := Mux(
383      isAfter(cmtPtrExt(0), deqPtrExt(0)),
384      cmtPtrExt(0),
385      deqPtrExtNext(0) // for mmio insts, deqPtr may be ahead of cmtPtr
386    )
387  }
388
389  io.stAddrReadySqPtr := addrReadyPtrExt
390
391  // update
392  val dataReadyLookupVec = (0 until IssuePtrMoveStride).map(dataReadyPtrExt + _.U)
393  val dataReadyLookup = dataReadyLookupVec.map(ptr => allocated(ptr.value) &&
394   (mmio(ptr.value) || datavalid(ptr.value) || vecMbCommit(ptr.value))
395    && ptr =/= enqPtrExt(0))
396  val nextDataReadyPtr = dataReadyPtrExt + PriorityEncoder(VecInit(dataReadyLookup.map(!_) :+ true.B))
397  dataReadyPtrExt := nextDataReadyPtr
398
399  (0 until StoreQueueSize).map(i => {
400    io.stDataReadyVec(i) := RegNext(allocated(i) && (mmio(i) || datavalid(i) || (isVec(i) && vecMbCommit(i))))
401  })
402
403  when (io.brqRedirect.valid) {
404    dataReadyPtrExt := Mux(
405      isAfter(cmtPtrExt(0), deqPtrExt(0)),
406      cmtPtrExt(0),
407      deqPtrExtNext(0) // for mmio insts, deqPtr may be ahead of cmtPtr
408    )
409  }
410
411  io.stDataReadySqPtr := dataReadyPtrExt
412  io.stIssuePtr := enqPtrExt(0)
413  io.sqDeqPtr := deqPtrExt(0)
414
415  /**
416    * Writeback store from store units
417    *
418    * Most store instructions writeback to regfile in the previous cycle.
419    * However,
420    *   (1) For an mmio instruction with exceptions, we need to mark it as addrvalid
421    * (in this way it will trigger an exception when it reaches ROB's head)
422    * instead of pending to avoid sending them to lower level.
423    *   (2) For an mmio instruction without exceptions, we mark it as pending.
424    * When the instruction reaches ROB's head, StoreQueue sends it to uncache channel.
425    * Upon receiving the response, StoreQueue writes back the instruction
426    * through arbiter with store units. It will later commit as normal.
427    */
428
429  // Write addr to sq
430  for (i <- 0 until StorePipelineWidth) {
431    paddrModule.io.wen(i) := false.B
432    vaddrModule.io.wen(i) := false.B
433    dataModule.io.mask.wen(i) := false.B
434    val stWbIndex = io.storeAddrIn(i).bits.uop.sqIdx.value
435    exceptionBuffer.io.storeAddrIn(i).valid := io.storeAddrIn(i).fire && !io.storeAddrIn(i).bits.miss && !io.storeAddrIn(i).bits.isvec
436    exceptionBuffer.io.storeAddrIn(i).bits := io.storeAddrIn(i).bits
437    // will re-enter exceptionbuffer at store_s2
438    exceptionBuffer.io.storeAddrIn(StorePipelineWidth + i).valid := false.B
439    exceptionBuffer.io.storeAddrIn(StorePipelineWidth + i).bits := 0.U.asTypeOf(new LsPipelineBundle)
440
441    when (io.storeAddrIn(i).fire) {
442      val addr_valid = !io.storeAddrIn(i).bits.miss
443      addrvalid(stWbIndex) := addr_valid //!io.storeAddrIn(i).bits.mmio
444      // pending(stWbIndex) := io.storeAddrIn(i).bits.mmio
445
446      paddrModule.io.waddr(i) := stWbIndex
447      paddrModule.io.wdata(i) := io.storeAddrIn(i).bits.paddr
448      paddrModule.io.wmask(i) := io.storeAddrIn(i).bits.mask
449      paddrModule.io.wlineflag(i) := io.storeAddrIn(i).bits.wlineflag
450      paddrModule.io.wen(i) := true.B
451
452      vaddrModule.io.waddr(i) := stWbIndex
453      vaddrModule.io.wdata(i) := io.storeAddrIn(i).bits.vaddr
454      vaddrModule.io.wmask(i) := io.storeAddrIn(i).bits.mask
455      vaddrModule.io.wlineflag(i) := io.storeAddrIn(i).bits.wlineflag
456      vaddrModule.io.wen(i) := true.B
457
458      debug_paddr(paddrModule.io.waddr(i)) := paddrModule.io.wdata(i)
459
460      // mmio(stWbIndex) := io.storeAddrIn(i).bits.mmio
461
462      uop(stWbIndex) := io.storeAddrIn(i).bits.uop
463      uop(stWbIndex).debugInfo := io.storeAddrIn(i).bits.uop.debugInfo
464
465      vecDataValid(stWbIndex) := io.storeAddrIn(i).bits.isvec
466
467      XSInfo("store addr write to sq idx %d pc 0x%x miss:%d vaddr %x paddr %x mmio %x isvec %x\n",
468        io.storeAddrIn(i).bits.uop.sqIdx.value,
469        io.storeAddrIn(i).bits.uop.pc,
470        io.storeAddrIn(i).bits.miss,
471        io.storeAddrIn(i).bits.vaddr,
472        io.storeAddrIn(i).bits.paddr,
473        io.storeAddrIn(i).bits.mmio,
474        io.storeAddrIn(i).bits.isvec
475      )
476    }
477
478    // re-replinish mmio, for pma/pmp will get mmio one cycle later
479    val storeAddrInFireReg = RegNext(io.storeAddrIn(i).fire && !io.storeAddrIn(i).bits.miss)
480    val stWbIndexReg = RegNext(stWbIndex)
481    when (storeAddrInFireReg) {
482      pending(stWbIndexReg) := io.storeAddrInRe(i).mmio
483      mmio(stWbIndexReg) := io.storeAddrInRe(i).mmio
484      atomic(stWbIndexReg) := io.storeAddrInRe(i).atomic
485      hasException(stWbIndexReg) := ExceptionNO.selectByFu(uop(stWbIndexReg).exceptionVec, StaCfg).asUInt.orR || io.storeAddrInRe(i).af
486      waitStoreS2(stWbIndexReg) := false.B
487    }
488    // dcache miss info (one cycle later than storeIn)
489    // if dcache report a miss in sta pipeline, this store will trigger a prefetch when committing to sbuffer (if EnableAtCommitMissTrigger)
490    when (storeAddrInFireReg) {
491      prefetch(stWbIndexReg) := io.storeAddrInRe(i).miss
492    }
493    // enter exceptionbuffer again
494    when (storeAddrInFireReg) {
495      exceptionBuffer.io.storeAddrIn(StorePipelineWidth + i).valid := io.storeAddrInRe(i).af
496      exceptionBuffer.io.storeAddrIn(StorePipelineWidth + i).bits := RegEnable(io.storeAddrIn(i).bits, io.storeAddrIn(i).fire && !io.storeAddrIn(i).bits.miss)
497      exceptionBuffer.io.storeAddrIn(StorePipelineWidth + i).bits.uop.exceptionVec(storeAccessFault) := io.storeAddrInRe(i).af
498    }
499
500    when(vaddrModule.io.wen(i)){
501      debug_vaddr(vaddrModule.io.waddr(i)) := vaddrModule.io.wdata(i)
502    }
503  }
504
505  // Write data to sq
506  // Now store data pipeline is actually 2 stages
507  for (i <- 0 until StorePipelineWidth) {
508    dataModule.io.data.wen(i) := false.B
509    val stWbIndex = io.storeDataIn(i).bits.uop.sqIdx.value
510    val isVec     = FuType.isVStore(io.storeDataIn(i).bits.uop.fuType)
511    // sq data write takes 2 cycles:
512    // sq data write s0
513    when (io.storeDataIn(i).fire) {
514      // send data write req to data module
515      dataModule.io.data.waddr(i) := stWbIndex
516      dataModule.io.data.wdata(i) := Mux(io.storeDataIn(i).bits.uop.fuOpType === LSUOpType.cbo_zero,
517        0.U,
518        Mux(isVec,
519          io.storeDataIn(i).bits.data,
520          genVWdata(io.storeDataIn(i).bits.data, io.storeDataIn(i).bits.uop.fuOpType(2,0)))
521      )
522      dataModule.io.data.wen(i) := true.B
523
524      debug_data(dataModule.io.data.waddr(i)) := dataModule.io.data.wdata(i)
525
526      XSInfo("store data write to sq idx %d pc 0x%x data %x -> %x\n",
527        io.storeDataIn(i).bits.uop.sqIdx.value,
528        io.storeDataIn(i).bits.uop.pc,
529        io.storeDataIn(i).bits.data,
530        dataModule.io.data.wdata(i)
531      )
532    }
533    // sq data write s1
534    when (
535      RegNext(io.storeDataIn(i).fire)
536      // && !RegNext(io.storeDataIn(i).bits.uop).robIdx.needFlush(io.brqRedirect)
537    ) {
538      datavalid(RegNext(stWbIndex)) := true.B
539    }
540  }
541
542  // Write mask to sq
543  for (i <- 0 until StorePipelineWidth) {
544    // sq mask write s0
545    when (io.storeMaskIn(i).fire) {
546      // send data write req to data module
547      dataModule.io.mask.waddr(i) := io.storeMaskIn(i).bits.sqIdx.value
548      dataModule.io.mask.wdata(i) := io.storeMaskIn(i).bits.mask
549      dataModule.io.mask.wen(i) := true.B
550    }
551  }
552
553  /**
554    * load forward query
555    *
556    * Check store queue for instructions that is older than the load.
557    * The response will be valid at the next cycle after req.
558    */
559  // check over all lq entries and forward data from the first matched store
560  for (i <- 0 until LoadPipelineWidth) {
561    // Compare deqPtr (deqPtr) and forward.sqIdx, we have two cases:
562    // (1) if they have the same flag, we need to check range(tail, sqIdx)
563    // (2) if they have different flags, we need to check range(tail, VirtualLoadQueueSize) and range(0, sqIdx)
564    // Forward1: Mux(same_flag, range(tail, sqIdx), range(tail, VirtualLoadQueueSize))
565    // Forward2: Mux(same_flag, 0.U,                   range(0, sqIdx)    )
566    // i.e. forward1 is the target entries with the same flag bits and forward2 otherwise
567    val differentFlag = deqPtrExt(0).flag =/= io.forward(i).sqIdx.flag
568    val forwardMask = io.forward(i).sqIdxMask
569    // all addrvalid terms need to be checked
570    // Real Vaild: all scalar stores, and vector store with (!inactive && !secondInvalid)
571    val addrRealValidVec = WireInit(VecInit((0 until StoreQueueSize).map(j => addrvalid(j) && allocated(j))))
572    // vector store will consider all inactive || secondInvalid flows as valid
573    val addrValidVec = WireInit(VecInit((0 until StoreQueueSize).map(j => addrvalid(j) && allocated(j))))
574    val dataValidVec = WireInit(VecInit((0 until StoreQueueSize).map(j => datavalid(j))))
575    val allValidVec  = WireInit(VecInit((0 until StoreQueueSize).map(j => addrvalid(j) && datavalid(j) && allocated(j))))
576
577    val lfstEnable = Constantin.createRecord("LFSTEnable", LFSTEnable)
578    val storeSetHitVec = Mux(lfstEnable,
579      WireInit(VecInit((0 until StoreQueueSize).map(j => io.forward(i).uop.loadWaitBit && uop(j).robIdx === io.forward(i).uop.waitForRobIdx))),
580      WireInit(VecInit((0 until StoreQueueSize).map(j => uop(j).storeSetHit && uop(j).ssid === io.forward(i).uop.ssid)))
581    )
582
583    val forwardMask1 = Mux(differentFlag, ~deqMask, deqMask ^ forwardMask)
584    val forwardMask2 = Mux(differentFlag, forwardMask, 0.U(StoreQueueSize.W))
585    val canForward1 = forwardMask1 & allValidVec.asUInt
586    val canForward2 = forwardMask2 & allValidVec.asUInt
587    val needForward = Mux(differentFlag, ~deqMask | forwardMask, deqMask ^ forwardMask)
588
589    XSDebug(p"$i f1 ${Binary(canForward1)} f2 ${Binary(canForward2)} " +
590      p"sqIdx ${io.forward(i).sqIdx} pa ${Hexadecimal(io.forward(i).paddr)}\n"
591    )
592
593    // do real fwd query (cam lookup in load_s1)
594    dataModule.io.needForward(i)(0) := canForward1 & vaddrModule.io.forwardMmask(i).asUInt
595    dataModule.io.needForward(i)(1) := canForward2 & vaddrModule.io.forwardMmask(i).asUInt
596
597    vaddrModule.io.forwardMdata(i) := io.forward(i).vaddr
598    vaddrModule.io.forwardDataMask(i) := io.forward(i).mask
599    paddrModule.io.forwardMdata(i) := io.forward(i).paddr
600    paddrModule.io.forwardDataMask(i) := io.forward(i).mask
601
602    // vaddr cam result does not equal to paddr cam result
603    // replay needed
604    // val vpmaskNotEqual = ((paddrModule.io.forwardMmask(i).asUInt ^ vaddrModule.io.forwardMmask(i).asUInt) & needForward) =/= 0.U
605    // val vaddrMatchFailed = vpmaskNotEqual && io.forward(i).valid
606    val vpmaskNotEqual = (
607      (RegNext(paddrModule.io.forwardMmask(i).asUInt) ^ RegNext(vaddrModule.io.forwardMmask(i).asUInt)) &
608      RegNext(needForward) &
609      RegNext(addrRealValidVec.asUInt)
610    ) =/= 0.U
611    val vaddrMatchFailed = vpmaskNotEqual && RegNext(io.forward(i).valid)
612    when (vaddrMatchFailed) {
613      XSInfo("vaddrMatchFailed: pc %x pmask %x vmask %x\n",
614        RegNext(io.forward(i).uop.pc),
615        RegNext(needForward & paddrModule.io.forwardMmask(i).asUInt),
616        RegNext(needForward & vaddrModule.io.forwardMmask(i).asUInt)
617      );
618    }
619    XSPerfAccumulate("vaddr_match_failed", vpmaskNotEqual)
620    XSPerfAccumulate("vaddr_match_really_failed", vaddrMatchFailed)
621
622    // Fast forward mask will be generated immediately (load_s1)
623    io.forward(i).forwardMaskFast := dataModule.io.forwardMaskFast(i)
624
625    // Forward result will be generated 1 cycle later (load_s2)
626    io.forward(i).forwardMask := dataModule.io.forwardMask(i)
627    io.forward(i).forwardData := dataModule.io.forwardData(i)
628    // If addr match, data not ready, mark it as dataInvalid
629    // load_s1: generate dataInvalid in load_s1 to set fastUop
630    val dataInvalidMask1 = (addrValidVec.asUInt & ~dataValidVec.asUInt & vaddrModule.io.forwardMmask(i).asUInt & forwardMask1.asUInt)
631    val dataInvalidMask2 = (addrValidVec.asUInt & ~dataValidVec.asUInt & vaddrModule.io.forwardMmask(i).asUInt & forwardMask2.asUInt)
632    val dataInvalidMask = dataInvalidMask1 | dataInvalidMask2
633    io.forward(i).dataInvalidFast := dataInvalidMask.orR
634
635    // make chisel happy
636    val dataInvalidMask1Reg = Wire(UInt(StoreQueueSize.W))
637    dataInvalidMask1Reg := RegNext(dataInvalidMask1)
638    // make chisel happy
639    val dataInvalidMask2Reg = Wire(UInt(StoreQueueSize.W))
640    dataInvalidMask2Reg := RegNext(dataInvalidMask2)
641    val dataInvalidMaskReg = dataInvalidMask1Reg | dataInvalidMask2Reg
642
643    // If SSID match, address not ready, mark it as addrInvalid
644    // load_s2: generate addrInvalid
645    val addrInvalidMask1 = (~addrValidVec.asUInt & storeSetHitVec.asUInt & forwardMask1.asUInt)
646    val addrInvalidMask2 = (~addrValidVec.asUInt & storeSetHitVec.asUInt & forwardMask2.asUInt)
647    // make chisel happy
648    val addrInvalidMask1Reg = Wire(UInt(StoreQueueSize.W))
649    addrInvalidMask1Reg := RegNext(addrInvalidMask1)
650    // make chisel happy
651    val addrInvalidMask2Reg = Wire(UInt(StoreQueueSize.W))
652    addrInvalidMask2Reg := RegNext(addrInvalidMask2)
653    val addrInvalidMaskReg = addrInvalidMask1Reg | addrInvalidMask2Reg
654
655    // load_s2
656    io.forward(i).dataInvalid := RegNext(io.forward(i).dataInvalidFast)
657    // check if vaddr forward mismatched
658    io.forward(i).matchInvalid := vaddrMatchFailed
659
660    // data invalid sq index
661    // check whether false fail
662    // check flag
663    val s2_differentFlag = RegNext(differentFlag)
664    val s2_enqPtrExt = RegNext(enqPtrExt(0))
665    val s2_deqPtrExt = RegNext(deqPtrExt(0))
666
667    // addr invalid sq index
668    // make chisel happy
669    val addrInvalidMaskRegWire = Wire(UInt(StoreQueueSize.W))
670    addrInvalidMaskRegWire := addrInvalidMaskReg
671    val addrInvalidFlag = addrInvalidMaskRegWire.orR
672    val hasInvalidAddr = (~addrValidVec.asUInt & needForward).orR
673
674    val addrInvalidSqIdx1 = OHToUInt(Reverse(PriorityEncoderOH(Reverse(addrInvalidMask1Reg))))
675    val addrInvalidSqIdx2 = OHToUInt(Reverse(PriorityEncoderOH(Reverse(addrInvalidMask2Reg))))
676    val addrInvalidSqIdx = Mux(addrInvalidMask2Reg.orR, addrInvalidSqIdx2, addrInvalidSqIdx1)
677
678    // store-set content management
679    //                +-----------------------+
680    //                | Search a SSID for the |
681    //                |    load operation     |
682    //                +-----------------------+
683    //                           |
684    //                           V
685    //                 +-------------------+
686    //                 | load wait strict? |
687    //                 +-------------------+
688    //                           |
689    //                           V
690    //               +----------------------+
691    //            Set|                      |Clean
692    //               V                      V
693    //  +------------------------+   +------------------------------+
694    //  | Waiting for all older  |   | Wait until the corresponding |
695    //  |   stores operations    |   | older store operations       |
696    //  +------------------------+   +------------------------------+
697
698
699
700    when (RegNext(io.forward(i).uop.loadWaitStrict)) {
701      io.forward(i).addrInvalidSqIdx := RegNext(io.forward(i).uop.sqIdx - 1.U)
702    } .elsewhen (addrInvalidFlag) {
703      io.forward(i).addrInvalidSqIdx.flag := Mux(!s2_differentFlag || addrInvalidSqIdx >= s2_deqPtrExt.value, s2_deqPtrExt.flag, s2_enqPtrExt.flag)
704      io.forward(i).addrInvalidSqIdx.value := addrInvalidSqIdx
705    } .otherwise {
706      // may be store inst has been written to sbuffer already.
707      io.forward(i).addrInvalidSqIdx := RegNext(io.forward(i).uop.sqIdx)
708    }
709    io.forward(i).addrInvalid := Mux(RegNext(io.forward(i).uop.loadWaitStrict), RegNext(hasInvalidAddr), addrInvalidFlag)
710
711    // data invalid sq index
712    // make chisel happy
713    val dataInvalidMaskRegWire = Wire(UInt(StoreQueueSize.W))
714    dataInvalidMaskRegWire := dataInvalidMaskReg
715    val dataInvalidFlag = dataInvalidMaskRegWire.orR
716
717    val dataInvalidSqIdx1 = OHToUInt(Reverse(PriorityEncoderOH(Reverse(dataInvalidMask1Reg))))
718    val dataInvalidSqIdx2 = OHToUInt(Reverse(PriorityEncoderOH(Reverse(dataInvalidMask2Reg))))
719    val dataInvalidSqIdx = Mux(dataInvalidMask2Reg.orR, dataInvalidSqIdx2, dataInvalidSqIdx1)
720
721    when (dataInvalidFlag) {
722      io.forward(i).dataInvalidSqIdx.flag := Mux(!s2_differentFlag || dataInvalidSqIdx >= s2_deqPtrExt.value, s2_deqPtrExt.flag, s2_enqPtrExt.flag)
723      io.forward(i).dataInvalidSqIdx.value := dataInvalidSqIdx
724    } .otherwise {
725      // may be store inst has been written to sbuffer already.
726      io.forward(i).dataInvalidSqIdx := RegNext(io.forward(i).uop.sqIdx)
727    }
728  }
729
730  /**
731    * Memory mapped IO / other uncached operations
732    *
733    * States:
734    * (1) writeback from store units: mark as pending
735    * (2) when they reach ROB's head, they can be sent to uncache channel
736    * (3) response from uncache channel: mark as datavalidmask.wen
737    * (4) writeback to ROB (and other units): mark as writebacked
738    * (5) ROB commits the instruction: same as normal instructions
739    */
740  //(2) when they reach ROB's head, they can be sent to uncache channel
741  // TODO: CAN NOT deal with vector mmio now!
742  val s_idle :: s_req :: s_resp :: s_wb :: s_wait :: Nil = Enum(5)
743  val uncacheState = RegInit(s_idle)
744  val uncacheUop = Reg(new DynInst)
745  switch(uncacheState) {
746    is(s_idle) {
747      when(RegNext(io.rob.pendingst && uop(deqPtr).robIdx === io.rob.pendingPtr && pending(deqPtr) && allocated(deqPtr) && datavalid(deqPtr) && addrvalid(deqPtr))) {
748        uncacheState := s_req
749        uncacheUop := uop(deqPtr)
750      }
751    }
752    is(s_req) {
753      when (io.uncache.req.fire) {
754        when (io.uncacheOutstanding) {
755          uncacheState := s_wb
756        } .otherwise {
757          uncacheState := s_resp
758        }
759      }
760    }
761    is(s_resp) {
762      when(io.uncache.resp.fire) {
763        uncacheState := s_wb
764
765        when (io.uncache.resp.bits.nderr) {
766          uop(deqPtr).exceptionVec(storeAccessFault) := true.B
767        }
768      }
769    }
770    is(s_wb) {
771      when (io.mmioStout.fire || io.vecmmioStout.fire) {
772        uncacheState := s_wait
773      }
774    }
775    is(s_wait) {
776      // A MMIO store can always move cmtPtrExt as it must be ROB head
777      when(scommit > 0.U) {
778        uncacheState := s_idle // ready for next mmio
779      }
780    }
781  }
782  io.uncache.req.valid := uncacheState === s_req
783
784  io.uncache.req.bits := DontCare
785  io.uncache.req.bits.cmd  := MemoryOpConstants.M_XWR
786  io.uncache.req.bits.addr := paddrModule.io.rdata(0) // data(deqPtr) -> rdata(0)
787  io.uncache.req.bits.data := shiftDataToLow(paddrModule.io.rdata(0), dataModule.io.rdata(0).data)
788  io.uncache.req.bits.mask := shiftMaskToLow(paddrModule.io.rdata(0), dataModule.io.rdata(0).mask)
789
790  // CBO op type check can be delayed for 1 cycle,
791  // as uncache op will not start in s_idle
792  val cbo_mmio_addr = paddrModule.io.rdata(0) >> 2 << 2 // clear lowest 2 bits for op
793  val cbo_mmio_op = 0.U //TODO
794  val cbo_mmio_data = cbo_mmio_addr | cbo_mmio_op
795  when(RegNext(LSUOpType.isCbo(uop(deqPtr).fuOpType))){
796    io.uncache.req.bits.addr := DontCare // TODO
797    io.uncache.req.bits.data := paddrModule.io.rdata(0)
798    io.uncache.req.bits.mask := DontCare // TODO
799  }
800
801  io.uncache.req.bits.atomic := atomic(RegNext(rdataPtrExtNext(0)).value)
802
803  when(io.uncache.req.fire){
804    // mmio store should not be committed until uncache req is sent
805    pending(deqPtr) := false.B
806
807    XSDebug(
808      p"uncache req: pc ${Hexadecimal(uop(deqPtr).pc)} " +
809      p"addr ${Hexadecimal(io.uncache.req.bits.addr)} " +
810      p"data ${Hexadecimal(io.uncache.req.bits.data)} " +
811      p"op ${Hexadecimal(io.uncache.req.bits.cmd)} " +
812      p"mask ${Hexadecimal(io.uncache.req.bits.mask)}\n"
813    )
814  }
815
816  // (3) response from uncache channel: mark as datavalid
817  io.uncache.resp.ready := true.B
818
819  // (4) scalar store: writeback to ROB (and other units): mark as writebacked
820  io.mmioStout.valid := uncacheState === s_wb && !isVec(deqPtr)
821  io.mmioStout.bits.uop := uncacheUop
822  io.mmioStout.bits.uop.sqIdx := deqPtrExt(0)
823  io.mmioStout.bits.data := shiftDataToLow(paddrModule.io.rdata(0), dataModule.io.rdata(0).data) // dataModule.io.rdata.read(deqPtr)
824  io.mmioStout.bits.debug.isMMIO := true.B
825  io.mmioStout.bits.debug.paddr := DontCare
826  io.mmioStout.bits.debug.isPerfCnt := false.B
827  io.mmioStout.bits.debug.vaddr := DontCare
828  // Remove MMIO inst from store queue after MMIO request is being sent
829  // That inst will be traced by uncache state machine
830  when (io.mmioStout.fire) {
831    allocated(deqPtr) := false.B
832  }
833
834  // (4) or vector store:
835  // TODO: implement it!
836  io.vecmmioStout := DontCare
837  io.vecmmioStout.valid := uncacheState === s_wb && isVec(deqPtr)
838  io.vecmmioStout.bits.uop := uop(deqPtr)
839  io.vecmmioStout.bits.uop.sqIdx := deqPtrExt(0)
840  io.vecmmioStout.bits.data := shiftDataToLow(paddrModule.io.rdata(0), dataModule.io.rdata(0).data) // dataModule.io.rdata.read(deqPtr)
841  io.vecmmioStout.bits.debug.isMMIO := true.B
842  io.vecmmioStout.bits.debug.paddr := DontCare
843  io.vecmmioStout.bits.debug.isPerfCnt := false.B
844  io.vecmmioStout.bits.debug.vaddr := DontCare
845  // Remove MMIO inst from store queue after MMIO request is being sent
846  // That inst will be traced by uncache state machine
847  when (io.vecmmioStout.fire) {
848    allocated(deqPtr) := false.B
849  }
850
851  /**
852    * ROB commits store instructions (mark them as committed)
853    *
854    * (1) When store commits, mark it as committed.
855    * (2) They will not be cancelled and can be sent to lower level.
856    */
857  XSError(uncacheState =/= s_idle && uncacheState =/= s_wait && commitCount > 0.U,
858   "should not commit instruction when MMIO has not been finished\n")
859
860  val commitVec = WireInit(VecInit(Seq.fill(CommitWidth)(false.B)))
861  val needCancel = Wire(Vec(StoreQueueSize, Bool())) // Will be assigned later
862  dontTouch(commitVec)
863  // TODO: Deal with vector store mmio
864  for (i <- 0 until CommitWidth) {
865    when (allocated(cmtPtrExt(i).value) && isNotAfter(uop(cmtPtrExt(i).value).robIdx, RegNext(io.rob.pendingPtr)) && !needCancel(cmtPtrExt(i).value) && (!waitStoreS2(cmtPtrExt(i).value) || isVec(cmtPtrExt(i).value))) {
866      if (i == 0){
867        // TODO: fixme for vector mmio
868        when ((uncacheState === s_idle) || (uncacheState === s_wait && scommit > 0.U)){
869          when ((isVec(cmtPtrExt(i).value) && vecMbCommit(cmtPtrExt(i).value)) || !isVec(cmtPtrExt(i).value)) {
870            committed(cmtPtrExt(0).value) := true.B
871            commitVec(0) := true.B
872          }
873        }
874      } else {
875        when ((isVec(cmtPtrExt(i).value) && vecMbCommit(cmtPtrExt(i).value)) || !isVec(cmtPtrExt(i).value)) {
876          committed(cmtPtrExt(i).value) := commitVec(i - 1) || committed(cmtPtrExt(i).value)
877          commitVec(i) := commitVec(i - 1)
878        }
879      }
880    }
881  }
882
883  commitCount := PopCount(commitVec)
884  cmtPtrExt := cmtPtrExt.map(_ + commitCount)
885
886  // committed stores will not be cancelled and can be sent to lower level.
887  // remove retired insts from sq, add retired store to sbuffer
888
889  // Read data from data module
890  // As store queue grows larger and larger, time needed to read data from data
891  // module keeps growing higher. Now we give data read a whole cycle.
892  for (i <- 0 until EnsbufferWidth) {
893    val ptr = rdataPtrExt(i).value
894    val mmioStall = if(i == 0) mmio(rdataPtrExt(0).value) else (mmio(rdataPtrExt(i).value) || mmio(rdataPtrExt(i-1).value))
895    val exceptionValid = if(i == 0) hasException(rdataPtrExt(0).value) else {
896      hasException(rdataPtrExt(i).value) || (hasException(rdataPtrExt(i-1).value) && uop(rdataPtrExt(i).value).robIdx === uop(rdataPtrExt(i-1).value).robIdx)
897    }
898    // Vector instructions that prevent triggered exceptions from being written to the 'databuffer'.
899    val vecHasExceptionFlagValid = vecExceptionFlag.valid && isVec(ptr) && vecExceptionFlag.bits.robIdx === uop(ptr).robIdx
900    dataBuffer.io.enq(i).valid := allocated(ptr) && committed(ptr) && ((!isVec(ptr) && (allvalid(ptr) || hasException(ptr))) || vecMbCommit(ptr)) && !mmioStall
901    // Note that store data/addr should both be valid after store's commit
902    assert(!dataBuffer.io.enq(i).valid || allvalid(ptr) || (allocated(ptr) && vecMbCommit(ptr)))
903    dataBuffer.io.enq(i).bits.addr     := paddrModule.io.rdata(i)
904    dataBuffer.io.enq(i).bits.vaddr    := vaddrModule.io.rdata(i)
905    dataBuffer.io.enq(i).bits.data     := dataModule.io.rdata(i).data
906    dataBuffer.io.enq(i).bits.mask     := dataModule.io.rdata(i).mask
907    dataBuffer.io.enq(i).bits.wline    := paddrModule.io.rlineflag(i)
908    dataBuffer.io.enq(i).bits.sqPtr    := rdataPtrExt(i)
909    dataBuffer.io.enq(i).bits.prefetch := prefetch(ptr)
910    // when scalar has exception, will also not write into sbuffer
911    dataBuffer.io.enq(i).bits.vecValid := (!isVec(ptr) || vecDataValid(ptr)) && !exceptionValid && !vecHasExceptionFlagValid
912//    dataBuffer.io.enq(i).bits.vecValid := (!isVec(ptr) || vecDataValid(ptr)) && !hasException(ptr)
913  }
914
915  // Send data stored in sbufferReqBitsReg to sbuffer
916  for (i <- 0 until EnsbufferWidth) {
917    io.sbuffer(i).valid := dataBuffer.io.deq(i).valid
918    dataBuffer.io.deq(i).ready := io.sbuffer(i).ready
919    // Write line request should have all 1 mask
920    assert(!(io.sbuffer(i).valid && io.sbuffer(i).bits.wline && io.sbuffer(i).bits.vecValid && !io.sbuffer(i).bits.mask.andR))
921    io.sbuffer(i).bits := DontCare
922    io.sbuffer(i).bits.cmd   := MemoryOpConstants.M_XWR
923    io.sbuffer(i).bits.addr  := dataBuffer.io.deq(i).bits.addr
924    io.sbuffer(i).bits.vaddr := dataBuffer.io.deq(i).bits.vaddr
925    io.sbuffer(i).bits.data  := dataBuffer.io.deq(i).bits.data
926    io.sbuffer(i).bits.mask  := dataBuffer.io.deq(i).bits.mask
927    io.sbuffer(i).bits.wline := dataBuffer.io.deq(i).bits.wline && dataBuffer.io.deq(i).bits.vecValid
928    io.sbuffer(i).bits.prefetch := dataBuffer.io.deq(i).bits.prefetch
929    io.sbuffer(i).bits.vecValid := dataBuffer.io.deq(i).bits.vecValid
930    // io.sbuffer(i).fire is RegNexted, as sbuffer data write takes 2 cycles.
931    // Before data write finish, sbuffer is unable to provide store to load
932    // forward data. As an workaround, deqPtrExt and allocated flag update
933    // is delayed so that load can get the right data from store queue.
934    val ptr = dataBuffer.io.deq(i).bits.sqPtr.value
935    when (RegNext(io.sbuffer(i).fire)) {
936      allocated(RegEnable(ptr, io.sbuffer(i).fire)) := false.B
937      XSDebug("sbuffer "+i+" fire: ptr %d\n", ptr)
938    }
939  }
940
941  // All vector instruction uop normally dequeue, but the Uop after the exception is raised does not write to the 'sbuffer'.
942  // Flags are used to record whether there are any exceptions when the queue is displayed.
943  // This is determined each time a write is made to the 'databuffer', prevent subsequent uop of the same instruction from writing to the 'dataBuffer'.
944  val vecCommitHasException = (0 until EnsbufferWidth).map{ i =>
945    val ptr                 = rdataPtrExt(i).value
946    val mmioStall           = if(i == 0) mmio(rdataPtrExt(0).value) else (mmio(rdataPtrExt(i).value) || mmio(rdataPtrExt(i-1).value))
947    val exceptionVliad      = allocated(ptr) && committed(ptr) && vecMbCommit(ptr) && !mmioStall && isVec(ptr) && vecDataValid(ptr) && hasException(ptr)
948    (exceptionVliad, uop(ptr))
949  }
950
951  val vecCommitHasExceptionValid      = vecCommitHasException.map(_._1)
952  val vecCommitHasExceptionUop        = vecCommitHasException.map(_._2)
953  val vecCommitHasExceptionValidOR    = vecCommitHasExceptionValid.reduce(_ || _)
954  // Just select the last Uop tah has an exception.
955  val vecCommitHasExceptionSelectUop  = ParallelPosteriorityMux(vecCommitHasExceptionValid, vecCommitHasExceptionUop)
956  // If the last Uop with an exception is the LastUop of this instruction, the flag is not set.
957  val vecCommitLastUop = vecCommitHasExceptionSelectUop.lastUop
958
959  val vecExceptionFlagCancel  = (0 until EnsbufferWidth).map{ i =>
960    val ptr                   = rdataPtrExt(i).value
961    val mmioStall             = if(i == 0) mmio(rdataPtrExt(0).value) else (mmio(rdataPtrExt(i).value) || mmio(rdataPtrExt(i-1).value))
962    val vecLastUopCommit      = uop(ptr).lastUop && (uop(ptr).robIdx === vecExceptionFlag.bits.robIdx) &&
963                                allocated(ptr) && committed(ptr) && vecMbCommit(ptr) && !mmioStall && isVec(ptr) && vecDataValid(ptr)
964    vecLastUopCommit
965  }.reduce(_ || _)
966
967  // When a LastUop with an exception instruction is commited, clear the flag.
968  when(!vecExceptionFlag.valid && vecCommitHasExceptionValidOR && !vecCommitLastUop) {
969    vecExceptionFlag.valid  := true.B
970    vecExceptionFlag.bits   := vecCommitHasExceptionSelectUop
971  }.elsewhen(vecExceptionFlag.valid && vecExceptionFlagCancel) {
972    vecExceptionFlag.valid  := false.B
973    vecExceptionFlag.bits   := 0.U.asTypeOf(new DynInst)
974  }
975
976  // A dumb defensive code. The flag should not be placed for a long period of time.
977  // A relatively large timeout period, not have any special meaning.
978  // If an assert appears and you confirm that it is not a Bug: Increase the timeout or remove the assert.
979  TimeOutAssert(vecExceptionFlag.valid, 3000, "vecExceptionFlag timeout, Plase check for bugs or add timeouts.")
980
981  // Initialize when unenabled difftest.
982  for (i <- 0 until EnsbufferWidth) {
983    io.sbufferVecDifftestInfo(i) := DontCare
984  }
985  // Consistent with the logic above.
986  // Only the vector store difftest required signal is separated from the rtl code.
987  if (env.EnableDifftest) {
988    for (i <- 0 until EnsbufferWidth) {
989      val ptr = rdataPtrExt(i).value
990      val mmioStall = if(i == 0) mmio(rdataPtrExt(0).value) else (mmio(rdataPtrExt(i).value) || mmio(rdataPtrExt(i-1).value))
991      difftestBuffer.get.io.enq(i).valid := allocated(ptr) && committed(ptr) && (!isVec(ptr) || vecMbCommit(ptr)) && !mmioStall
992      difftestBuffer.get.io.enq(i).bits := uop(ptr)
993    }
994    for (i <- 0 until EnsbufferWidth) {
995      io.sbufferVecDifftestInfo(i).valid := difftestBuffer.get.io.deq(i).valid
996      difftestBuffer.get.io.deq(i).ready := io.sbufferVecDifftestInfo(i).ready
997
998      io.sbufferVecDifftestInfo(i).bits := difftestBuffer.get.io.deq(i).bits
999    }
1000  }
1001
1002  (1 until EnsbufferWidth).foreach(i => when(io.sbuffer(i).fire) { assert(io.sbuffer(i - 1).fire) })
1003  if (coreParams.dcacheParametersOpt.isEmpty) {
1004    for (i <- 0 until EnsbufferWidth) {
1005      val ptr = deqPtrExt(i).value
1006      val ram = DifftestMem(64L * 1024 * 1024 * 1024, 8)
1007      val wen = allocated(ptr) && committed(ptr) && !mmio(ptr)
1008      val waddr = ((paddrModule.io.rdata(i) - "h80000000".U) >> 3).asUInt
1009      val wdata = Mux(paddrModule.io.rdata(i)(3), dataModule.io.rdata(i).data(127, 64), dataModule.io.rdata(i).data(63, 0))
1010      val wmask = Mux(paddrModule.io.rdata(i)(3), dataModule.io.rdata(i).mask(15, 8), dataModule.io.rdata(i).mask(7, 0))
1011      when (wen) {
1012        ram.write(waddr, wdata.asTypeOf(Vec(8, UInt(8.W))), wmask.asBools)
1013      }
1014    }
1015  }
1016
1017  // Read vaddr for mem exception
1018  io.exceptionAddr.vaddr  := exceptionBuffer.io.exceptionAddr.vaddr
1019  io.exceptionAddr.gpaddr  := exceptionBuffer.io.exceptionAddr.gpaddr
1020  io.exceptionAddr.vstart := exceptionBuffer.io.exceptionAddr.vstart
1021  io.exceptionAddr.vl     := exceptionBuffer.io.exceptionAddr.vl
1022
1023  // vector commit or replay from
1024  val vecCommittmp = Wire(Vec(StoreQueueSize, Vec(VecStorePipelineWidth, Bool())))
1025  val vecCommit = Wire(Vec(StoreQueueSize, Bool()))
1026  for (i <- 0 until StoreQueueSize) {
1027    val fbk = io.vecFeedback
1028    for (j <- 0 until VecStorePipelineWidth) {
1029      vecCommittmp(i)(j) := fbk(j).valid && (fbk(j).bits.isCommit || fbk(j).bits.isFlush) &&
1030        uop(i).robIdx === fbk(j).bits.robidx && uop(i).uopIdx === fbk(j).bits.uopidx && allocated(i)
1031    }
1032    vecCommit(i) := vecCommittmp(i).reduce(_ || _)
1033
1034    when (vecCommit(i)) {
1035      vecMbCommit(i) := true.B
1036    }
1037  }
1038
1039  // misprediction recovery / exception redirect
1040  // invalidate sq term using robIdx
1041  for (i <- 0 until StoreQueueSize) {
1042    needCancel(i) := uop(i).robIdx.needFlush(io.brqRedirect) && allocated(i) && !committed(i) &&
1043      (!isVec(i) || !(uop(i).robIdx === io.brqRedirect.bits.robIdx))
1044    when (needCancel(i)) {
1045      allocated(i) := false.B
1046    }
1047  }
1048
1049 /**
1050* update pointers
1051**/
1052  val enqCancelValid = canEnqueue.zip(io.enq.req).map{case (v , x) =>
1053    v && x.bits.robIdx.needFlush(io.brqRedirect)
1054  }
1055  val enqCancelNum = enqCancelValid.zip(io.enq.req).map{case (v, req) =>
1056    Mux(v, req.bits.numLsElem, 0.U)
1057  }
1058  val lastEnqCancel = RegNext(enqCancelNum.reduce(_ + _)) // 1 cycle after redirect
1059
1060  val lastCycleCancelCount = PopCount(RegNext(needCancel)) // 1 cycle after redirect
1061  val lastCycleRedirect = RegNext(io.brqRedirect.valid) // 1 cycle after redirect
1062  val enqNumber = validVStoreFlow.reduce(_ + _)
1063
1064  val lastlastCycleRedirect=RegNext(lastCycleRedirect)// 2 cycle after redirect
1065  val redirectCancelCount = RegEnable(lastCycleCancelCount + lastEnqCancel, lastCycleRedirect) // 2 cycle after redirect
1066
1067  when (lastlastCycleRedirect) {
1068    // we recover the pointers in 2 cycle after redirect for better timing
1069    enqPtrExt := VecInit(enqPtrExt.map(_ - redirectCancelCount))
1070  }.otherwise {
1071    // lastCycleRedirect.valid or nornal case
1072    // when lastCycleRedirect.valid, enqNumber === 0.U, enqPtrExt will not change
1073    enqPtrExt := VecInit(enqPtrExt.map(_ + enqNumber))
1074  }
1075  assert(!(lastCycleRedirect && enqNumber =/= 0.U))
1076
1077  deqPtrExt := deqPtrExtNext
1078  rdataPtrExt := rdataPtrExtNext
1079
1080  // val dequeueCount = Mux(io.sbuffer(1).fire, 2.U, Mux(io.sbuffer(0).fire || io.mmioStout.fire, 1.U, 0.U))
1081
1082  // If redirect at T0, sqCancelCnt is at T2
1083  io.sqCancelCnt := redirectCancelCount
1084  val ForceWriteUpper = Wire(UInt(log2Up(StoreQueueSize + 1).W))
1085  ForceWriteUpper := Constantin.createRecord(s"ForceWriteUpper_${p(XSCoreParamsKey).HartId}", initValue = 60)
1086  val ForceWriteLower = Wire(UInt(log2Up(StoreQueueSize + 1).W))
1087  ForceWriteLower := Constantin.createRecord(s"ForceWriteLower_${p(XSCoreParamsKey).HartId}", initValue = 55)
1088
1089  val valid_cnt = PopCount(allocated)
1090  io.force_write := RegNext(Mux(valid_cnt >= ForceWriteUpper, true.B, valid_cnt >= ForceWriteLower && io.force_write), init = false.B)
1091
1092  // io.sqempty will be used by sbuffer
1093  // We delay it for 1 cycle for better timing
1094  // When sbuffer need to check if it is empty, the pipeline is blocked, which means delay io.sqempty
1095  // for 1 cycle will also promise that sq is empty in that cycle
1096  io.sqEmpty := RegNext(
1097    enqPtrExt(0).value === deqPtrExt(0).value &&
1098    enqPtrExt(0).flag === deqPtrExt(0).flag
1099  )
1100  // perf counter
1101  QueuePerf(StoreQueueSize, validCount, !allowEnqueue)
1102  val vecValidVec = WireInit(VecInit((0 until StoreQueueSize).map(i => allocated(i) && isVec(i))))
1103  QueuePerf(StoreQueueSize, PopCount(vecValidVec), !allowEnqueue)
1104  io.sqFull := !allowEnqueue
1105  XSPerfAccumulate("mmioCycle", uncacheState =/= s_idle) // lq is busy dealing with uncache req
1106  XSPerfAccumulate("mmioCnt", io.uncache.req.fire)
1107  XSPerfAccumulate("mmio_wb_success", io.mmioStout.fire || io.vecmmioStout.fire)
1108  XSPerfAccumulate("mmio_wb_blocked", (io.mmioStout.valid && !io.mmioStout.ready) || (io.vecmmioStout.valid && !io.vecmmioStout.ready))
1109  XSPerfAccumulate("validEntryCnt", distanceBetween(enqPtrExt(0), deqPtrExt(0)))
1110  XSPerfAccumulate("cmtEntryCnt", distanceBetween(cmtPtrExt(0), deqPtrExt(0)))
1111  XSPerfAccumulate("nCmtEntryCnt", distanceBetween(enqPtrExt(0), cmtPtrExt(0)))
1112
1113  val perfValidCount = distanceBetween(enqPtrExt(0), deqPtrExt(0))
1114  val perfEvents = Seq(
1115    ("mmioCycle      ", uncacheState =/= s_idle),
1116    ("mmioCnt        ", io.uncache.req.fire),
1117    ("mmio_wb_success", io.mmioStout.fire || io.vecmmioStout.fire),
1118    ("mmio_wb_blocked", (io.mmioStout.valid && !io.mmioStout.ready) || (io.vecmmioStout.valid && !io.vecmmioStout.ready)),
1119    ("stq_1_4_valid  ", (perfValidCount < (StoreQueueSize.U/4.U))),
1120    ("stq_2_4_valid  ", (perfValidCount > (StoreQueueSize.U/4.U)) & (perfValidCount <= (StoreQueueSize.U/2.U))),
1121    ("stq_3_4_valid  ", (perfValidCount > (StoreQueueSize.U/2.U)) & (perfValidCount <= (StoreQueueSize.U*3.U/4.U))),
1122    ("stq_4_4_valid  ", (perfValidCount > (StoreQueueSize.U*3.U/4.U))),
1123  )
1124  generatePerfEvent()
1125
1126  // debug info
1127  XSDebug("enqPtrExt %d:%d deqPtrExt %d:%d\n", enqPtrExt(0).flag, enqPtr, deqPtrExt(0).flag, deqPtr)
1128
1129  def PrintFlag(flag: Bool, name: String): Unit = {
1130    when(flag) {
1131      XSDebug(false, true.B, name)
1132    }.otherwise {
1133      XSDebug(false, true.B, " ")
1134    }
1135  }
1136
1137  for (i <- 0 until StoreQueueSize) {
1138    XSDebug(s"$i: pc %x va %x pa %x data %x ",
1139      uop(i).pc,
1140      debug_vaddr(i),
1141      debug_paddr(i),
1142      debug_data(i)
1143    )
1144    PrintFlag(allocated(i), "a")
1145    PrintFlag(allocated(i) && addrvalid(i), "a")
1146    PrintFlag(allocated(i) && datavalid(i), "d")
1147    PrintFlag(allocated(i) && committed(i), "c")
1148    PrintFlag(allocated(i) && pending(i), "p")
1149    PrintFlag(allocated(i) && mmio(i), "m")
1150    XSDebug(false, true.B, "\n")
1151  }
1152
1153}
1154