xref: /XiangShan/src/main/scala/xiangshan/mem/lsqueue/LoadQueue.scala (revision 1a1319cb91d2e72427826c45de40c17e00a48b47)
1package xiangshan.mem
2
3import chisel3._
4import chisel3.util._
5import freechips.rocketchip.tile.HasFPUParameters
6import utils._
7import xiangshan._
8import xiangshan.cache._
9import xiangshan.cache.{DCacheLineIO, DCacheWordIO, MemoryOpConstants, TlbRequestIO}
10import xiangshan.backend.LSUOpType
11import xiangshan.mem._
12import xiangshan.backend.roq.RoqPtr
13import xiangshan.backend.fu.fpu.boxF32ToF64
14
15
16class LqPtr extends CircularQueuePtr(LqPtr.LoadQueueSize) { }
17
18object LqPtr extends HasXSParameter {
19  def apply(f: Bool, v: UInt): LqPtr = {
20    val ptr = Wire(new LqPtr)
21    ptr.flag := f
22    ptr.value := v
23    ptr
24  }
25}
26
27trait HasLoadHelper { this: XSModule =>
28  def rdataHelper(uop: MicroOp, rdata: UInt): UInt = {
29    val lwIntData = SignExt(rdata(31, 0), XLEN)
30    val ldIntData = SignExt(rdata(63, 0), XLEN)
31    val lwFpData = recode(rdata(31, 0), S)
32    val ldFpData = recode(rdata(63, 0), D)
33    val fpWen = uop.ctrl.fpWen
34    LookupTree(uop.ctrl.fuOpType, List(
35      LSUOpType.lb   -> SignExt(rdata(7, 0) , XLEN),
36      LSUOpType.lh   -> SignExt(rdata(15, 0), XLEN),
37      LSUOpType.lw   -> Mux(fpWen, lwFpData, lwIntData),
38      LSUOpType.ld   -> Mux(fpWen, ldFpData, ldIntData),
39      LSUOpType.lbu  -> ZeroExt(rdata(7, 0) , XLEN),
40      LSUOpType.lhu  -> ZeroExt(rdata(15, 0), XLEN),
41      LSUOpType.lwu  -> ZeroExt(rdata(31, 0), XLEN),
42    ))
43  }
44}
45
46
47// Load Queue
48class LoadQueue extends XSModule
49  with HasDCacheParameters
50  with HasCircularQueuePtrHelper
51  with HasLoadHelper
52{
53  val io = IO(new Bundle() {
54    val enq = new Bundle() {
55      val canAccept = Output(Bool())
56      val req = Vec(RenameWidth, Flipped(ValidIO(new MicroOp)))
57      val resp = Vec(RenameWidth, Output(new LqPtr))
58    }
59    val brqRedirect = Input(Valid(new Redirect))
60    val loadIn = Vec(LoadPipelineWidth, Flipped(Valid(new LsPipelineBundle)))
61    val storeIn = Vec(StorePipelineWidth, Flipped(Valid(new LsPipelineBundle))) // FIXME: Valid() only
62    val ldout = Vec(2, DecoupledIO(new ExuOutput)) // writeback load
63    val forward = Vec(LoadPipelineWidth, Flipped(new LoadForwardQueryIO))
64    val commits = Flipped(new RoqCommitIO)
65    val rollback = Output(Valid(new Redirect)) // replay now starts from load instead of store
66    val dcache = new DCacheLineIO
67    val uncache = new DCacheWordIO
68    val roqDeqPtr = Input(new RoqPtr)
69    val exceptionAddr = new ExceptionAddrIO
70    // val refill = Flipped(Valid(new DCacheLineReq ))
71  })
72
73  val uop = Reg(Vec(LoadQueueSize, new MicroOp))
74  // val data = Reg(Vec(LoadQueueSize, new LsRoqEntry))
75  val dataModule = Module(new LSQueueData(LoadQueueSize, LoadPipelineWidth))
76  dataModule.io := DontCare
77  val allocated = RegInit(VecInit(List.fill(LoadQueueSize)(false.B))) // lq entry has been allocated
78  val datavalid = RegInit(VecInit(List.fill(LoadQueueSize)(false.B))) // data is valid
79  val writebacked = RegInit(VecInit(List.fill(LoadQueueSize)(false.B))) // inst has been writebacked to CDB
80  val commited = Reg(Vec(LoadQueueSize, Bool())) // inst has been writebacked to CDB
81  val miss = Reg(Vec(LoadQueueSize, Bool())) // load inst missed, waiting for miss queue to accept miss request
82  val listening = Reg(Vec(LoadQueueSize, Bool())) // waiting for refill result
83  val pending = Reg(Vec(LoadQueueSize, Bool())) // mmio pending: inst is an mmio inst, it will not be executed until it reachs the end of roq
84
85  val enqPtrExt = RegInit(0.U.asTypeOf(new LqPtr))
86  val deqPtrExt = RegInit(0.U.asTypeOf(new LqPtr))
87  val enqPtr = enqPtrExt.value
88  val deqPtr = deqPtrExt.value
89  val sameFlag = enqPtrExt.flag === deqPtrExt.flag
90  val isEmpty = enqPtr === deqPtr && sameFlag
91  val isFull = enqPtr === deqPtr && !sameFlag
92  val allowIn = !isFull
93
94  val loadCommit = (0 until CommitWidth).map(i => io.commits.valid(i) && !io.commits.isWalk && io.commits.uop(i).ctrl.commitType === CommitType.LOAD)
95  val mcommitIdx = (0 until CommitWidth).map(i => io.commits.uop(i).lqIdx.value)
96
97  val deqMask = UIntToMask(deqPtr, LoadQueueSize)
98  val enqMask = UIntToMask(enqPtr, LoadQueueSize)
99  val enqDeqMask1 = deqMask ^ enqMask
100  val enqDeqMask = Mux(sameFlag, enqDeqMask1, ~enqDeqMask1)
101
102  // Enqueue at dispatch
103  val validEntries = distanceBetween(enqPtrExt, deqPtrExt)
104  val firedDispatch = io.enq.req.map(_.valid)
105  io.enq.canAccept := validEntries <= (LoadQueueSize - RenameWidth).U
106  XSDebug(p"(ready, valid): ${io.enq.canAccept}, ${Binary(Cat(firedDispatch))}\n")
107  for (i <- 0 until RenameWidth) {
108    val offset = if (i == 0) 0.U else PopCount((0 until i).map(firedDispatch(_)))
109    val lqIdx = enqPtrExt + offset
110    val index = lqIdx.value
111    when(io.enq.req(i).valid) {
112      uop(index) := io.enq.req(i).bits
113      allocated(index) := true.B
114      datavalid(index) := false.B
115      writebacked(index) := false.B
116      commited(index) := false.B
117      miss(index) := false.B
118      listening(index) := false.B
119      pending(index) := false.B
120    }
121    io.enq.resp(i) := lqIdx
122
123    XSError(!io.enq.canAccept && io.enq.req(i).valid, "should not valid when not ready\n")
124  }
125
126  when(Cat(firedDispatch).orR) {
127    enqPtrExt := enqPtrExt + PopCount(firedDispatch)
128    XSInfo("dispatched %d insts to lq\n", PopCount(firedDispatch))
129  }
130
131  // writeback load
132  (0 until LoadPipelineWidth).map(i => {
133    dataModule.io.wb(i).wen := false.B
134    when(io.loadIn(i).fire()) {
135      when(io.loadIn(i).bits.miss) {
136        XSInfo(io.loadIn(i).valid, "load miss write to lq idx %d pc 0x%x vaddr %x paddr %x data %x mask %x forwardData %x forwardMask: %x mmio %x roll %x exc %x\n",
137          io.loadIn(i).bits.uop.lqIdx.asUInt,
138          io.loadIn(i).bits.uop.cf.pc,
139          io.loadIn(i).bits.vaddr,
140          io.loadIn(i).bits.paddr,
141          io.loadIn(i).bits.data,
142          io.loadIn(i).bits.mask,
143          io.loadIn(i).bits.forwardData.asUInt,
144          io.loadIn(i).bits.forwardMask.asUInt,
145          io.loadIn(i).bits.mmio,
146          io.loadIn(i).bits.rollback,
147          io.loadIn(i).bits.uop.cf.exceptionVec.asUInt
148          )
149        }.otherwise {
150          XSInfo(io.loadIn(i).valid, "load hit write to cbd lqidx %d pc 0x%x vaddr %x paddr %x data %x mask %x forwardData %x forwardMask: %x mmio %x roll %x exc %x\n",
151          io.loadIn(i).bits.uop.lqIdx.asUInt,
152          io.loadIn(i).bits.uop.cf.pc,
153          io.loadIn(i).bits.vaddr,
154          io.loadIn(i).bits.paddr,
155          io.loadIn(i).bits.data,
156          io.loadIn(i).bits.mask,
157          io.loadIn(i).bits.forwardData.asUInt,
158          io.loadIn(i).bits.forwardMask.asUInt,
159          io.loadIn(i).bits.mmio,
160          io.loadIn(i).bits.rollback,
161          io.loadIn(i).bits.uop.cf.exceptionVec.asUInt
162          )
163        }
164        val loadWbIndex = io.loadIn(i).bits.uop.lqIdx.value
165        datavalid(loadWbIndex) := !io.loadIn(i).bits.miss && !io.loadIn(i).bits.mmio
166        writebacked(loadWbIndex) := !io.loadIn(i).bits.miss && !io.loadIn(i).bits.mmio
167        allocated(loadWbIndex) := !io.loadIn(i).bits.uop.cf.exceptionVec.asUInt.orR
168
169        val loadWbData = Wire(new LsqEntry)
170        loadWbData.paddr := io.loadIn(i).bits.paddr
171        loadWbData.vaddr := io.loadIn(i).bits.vaddr
172        loadWbData.mask := io.loadIn(i).bits.mask
173        loadWbData.data := io.loadIn(i).bits.data // for mmio / misc / debug
174        loadWbData.mmio := io.loadIn(i).bits.mmio
175        loadWbData.fwdMask := io.loadIn(i).bits.forwardMask
176        loadWbData.fwdData := io.loadIn(i).bits.forwardData
177        loadWbData.exception := io.loadIn(i).bits.uop.cf.exceptionVec.asUInt
178        dataModule.io.wbWrite(i, loadWbIndex, loadWbData)
179        dataModule.io.wb(i).wen := true.B
180
181        val dcacheMissed = io.loadIn(i).bits.miss && !io.loadIn(i).bits.mmio
182        miss(loadWbIndex) := dcacheMissed
183        listening(loadWbIndex) := dcacheMissed
184        pending(loadWbIndex) := io.loadIn(i).bits.mmio
185      }
186    })
187
188  // cache miss request
189  val inflightReqs = RegInit(VecInit(Seq.fill(cfg.nLoadMissEntries)(0.U.asTypeOf(new InflightBlockInfo))))
190  val inflightReqFull = inflightReqs.map(req => req.valid).reduce(_&&_)
191  val reqBlockIndex = PriorityEncoder(~VecInit(inflightReqs.map(req => req.valid)).asUInt)
192
193  val missRefillSelVec = VecInit(
194    (0 until LoadQueueSize).map{ i =>
195      val inflight = inflightReqs.map(req => req.valid && req.block_addr === get_block_addr(dataModule.io.rdata(i).paddr)).reduce(_||_)
196      allocated(i) && miss(i) && !inflight
197    })
198
199  val missRefillSel = getFirstOne(missRefillSelVec, deqMask)
200  val missRefillBlockAddr = get_block_addr(dataModule.io.rdata(missRefillSel).paddr)
201  io.dcache.req.valid := missRefillSelVec.asUInt.orR
202  io.dcache.req.bits.cmd := MemoryOpConstants.M_XRD
203  io.dcache.req.bits.addr := missRefillBlockAddr
204  io.dcache.req.bits.data := DontCare
205  io.dcache.req.bits.mask := DontCare
206
207  io.dcache.req.bits.meta.id       := DontCare
208  io.dcache.req.bits.meta.vaddr    := DontCare // dataModule.io.rdata(missRefillSel).vaddr
209  io.dcache.req.bits.meta.paddr    := missRefillBlockAddr
210  io.dcache.req.bits.meta.uop      := uop(missRefillSel)
211  io.dcache.req.bits.meta.mmio     := false.B // dataModule.io.rdata(missRefillSel).mmio
212  io.dcache.req.bits.meta.tlb_miss := false.B
213  io.dcache.req.bits.meta.mask     := DontCare
214  io.dcache.req.bits.meta.replay   := false.B
215
216  io.dcache.resp.ready := true.B
217
218  assert(!(dataModule.io.rdata(missRefillSel).mmio && io.dcache.req.valid))
219
220  when(io.dcache.req.fire()) {
221    miss(missRefillSel) := false.B
222    listening(missRefillSel) := true.B
223
224    // mark this block as inflight
225    inflightReqs(reqBlockIndex).valid := true.B
226    inflightReqs(reqBlockIndex).block_addr := missRefillBlockAddr
227    assert(!inflightReqs(reqBlockIndex).valid)
228  }
229
230  when(io.dcache.resp.fire()) {
231    val inflight = inflightReqs.map(req => req.valid && req.block_addr === get_block_addr(io.dcache.resp.bits.meta.paddr)).reduce(_||_)
232    assert(inflight)
233    for (i <- 0 until cfg.nLoadMissEntries) {
234      when (inflightReqs(i).valid && inflightReqs(i).block_addr === get_block_addr(io.dcache.resp.bits.meta.paddr)) {
235        inflightReqs(i).valid := false.B
236      }
237    }
238  }
239
240
241  when(io.dcache.req.fire()){
242    XSDebug("miss req: pc:0x%x roqIdx:%d lqIdx:%d (p)addr:0x%x vaddr:0x%x\n",
243      io.dcache.req.bits.meta.uop.cf.pc, io.dcache.req.bits.meta.uop.roqIdx.asUInt, io.dcache.req.bits.meta.uop.lqIdx.asUInt,
244      io.dcache.req.bits.addr, io.dcache.req.bits.meta.vaddr
245    )
246  }
247
248  when(io.dcache.resp.fire()){
249    XSDebug("miss resp: pc:0x%x roqIdx:%d lqIdx:%d (p)addr:0x%x data %x\n",
250      io.dcache.resp.bits.meta.uop.cf.pc, io.dcache.resp.bits.meta.uop.roqIdx.asUInt, io.dcache.resp.bits.meta.uop.lqIdx.asUInt,
251      io.dcache.resp.bits.meta.paddr, io.dcache.resp.bits.data
252    )
253  }
254
255  // Refill 64 bit in a cycle
256  // Refill data comes back from io.dcache.resp
257  dataModule.io.refill.dcache := io.dcache.resp.bits
258
259  (0 until LoadQueueSize).map(i => {
260    val blockMatch = get_block_addr(dataModule.io.rdata(i).paddr) === io.dcache.resp.bits.meta.paddr
261    dataModule.io.refill.wen(i) := false.B
262    when(allocated(i) && listening(i) && blockMatch && io.dcache.resp.fire()) {
263      dataModule.io.refill.wen(i) := true.B
264      datavalid(i) := true.B
265      listening(i) := false.B
266    }
267  })
268
269  // writeback up to 2 missed load insts to CDB
270  // just randomly pick 2 missed load (data refilled), write them back to cdb
271  val loadWbSelVec = VecInit((0 until LoadQueueSize).map(i => {
272    allocated(i) && datavalid(i) && !writebacked(i)
273  })).asUInt() // use uint instead vec to reduce verilog lines
274  val loadWbSel = Wire(Vec(StorePipelineWidth, UInt(log2Up(LoadQueueSize).W)))
275  val loadWbSelV= Wire(Vec(StorePipelineWidth, Bool()))
276  val lselvec0 = PriorityEncoderOH(loadWbSelVec)
277  val lselvec1 = PriorityEncoderOH(loadWbSelVec & (~lselvec0).asUInt)
278  loadWbSel(0) := OHToUInt(lselvec0)
279  loadWbSelV(0):= lselvec0.orR
280  loadWbSel(1) := OHToUInt(lselvec1)
281  loadWbSelV(1) := lselvec1.orR
282  (0 until StorePipelineWidth).map(i => {
283    // data select
284    val rdata = dataModule.io.rdata(loadWbSel(i)).data
285    val func = uop(loadWbSel(i)).ctrl.fuOpType
286    val raddr = dataModule.io.rdata(loadWbSel(i)).paddr
287    val rdataSel = LookupTree(raddr(2, 0), List(
288      "b000".U -> rdata(63, 0),
289      "b001".U -> rdata(63, 8),
290      "b010".U -> rdata(63, 16),
291      "b011".U -> rdata(63, 24),
292      "b100".U -> rdata(63, 32),
293      "b101".U -> rdata(63, 40),
294      "b110".U -> rdata(63, 48),
295      "b111".U -> rdata(63, 56)
296    ))
297    val rdataPartialLoad = rdataHelper(uop(loadWbSel(i)), rdataSel)
298    io.ldout(i).bits.uop := uop(loadWbSel(i))
299    io.ldout(i).bits.uop.cf.exceptionVec := dataModule.io.rdata(loadWbSel(i)).exception.asBools
300    io.ldout(i).bits.uop.lqIdx := loadWbSel(i).asTypeOf(new LqPtr)
301    io.ldout(i).bits.data := rdataPartialLoad
302    io.ldout(i).bits.redirectValid := false.B
303    io.ldout(i).bits.redirect := DontCare
304    io.ldout(i).bits.brUpdate := DontCare
305    io.ldout(i).bits.debug.isMMIO := dataModule.io.rdata(loadWbSel(i)).mmio
306    io.ldout(i).bits.fflags := DontCare
307    io.ldout(i).valid := loadWbSelVec(loadWbSel(i)) && loadWbSelV(i)
308    when(io.ldout(i).fire()) {
309      writebacked(loadWbSel(i)) := true.B
310      XSInfo("load miss write to cbd roqidx %d lqidx %d pc 0x%x paddr %x data %x mmio %x\n",
311        io.ldout(i).bits.uop.roqIdx.asUInt,
312        io.ldout(i).bits.uop.lqIdx.asUInt,
313        io.ldout(i).bits.uop.cf.pc,
314        dataModule.io.rdata(loadWbSel(i)).paddr,
315        dataModule.io.rdata(loadWbSel(i)).data,
316        dataModule.io.rdata(loadWbSel(i)).mmio
317      )
318    }
319  })
320
321  // move tailPtr
322  // allocatedMask: dequeuePtr can go to the next 1-bit
323  val allocatedMask = VecInit((0 until LoadQueueSize).map(i => allocated(i) || !enqDeqMask(i)))
324  // find the first one from deqPtr (deqPtr)
325  val nextTail1 = getFirstOneWithFlag(allocatedMask, deqMask, deqPtrExt.flag)
326  val nextTail = Mux(Cat(allocatedMask).orR, nextTail1, enqPtrExt)
327  deqPtrExt := nextTail
328
329  // When load commited, mark it as !allocated, this entry will be recycled later
330  (0 until CommitWidth).map(i => {
331    when(loadCommit(i)) {
332      allocated(mcommitIdx(i)) := false.B
333      XSDebug("load commit %d: idx %d %x\n", i.U, mcommitIdx(i), uop(mcommitIdx(i)).cf.pc)
334    }
335  })
336
337  def getFirstOne(mask: Vec[Bool], startMask: UInt) = {
338    val length = mask.length
339    val highBits = (0 until length).map(i => mask(i) & ~startMask(i))
340    val highBitsUint = Cat(highBits.reverse)
341    PriorityEncoder(Mux(highBitsUint.orR(), highBitsUint, mask.asUInt))
342  }
343
344  def getFirstOneWithFlag(mask: Vec[Bool], startMask: UInt, startFlag: Bool) = {
345    val length = mask.length
346    val highBits = (0 until length).map(i => mask(i) & ~startMask(i))
347    val highBitsUint = Cat(highBits.reverse)
348    val changeDirection = !highBitsUint.orR()
349    val index = PriorityEncoder(Mux(!changeDirection, highBitsUint, mask.asUInt))
350    LqPtr(startFlag ^ changeDirection, index)
351  }
352
353  def getOldestInTwo(valid: Seq[Bool], uop: Seq[MicroOp]) = {
354    assert(valid.length == uop.length)
355    assert(valid.length == 2)
356    Mux(valid(0) && valid(1),
357      Mux(isAfter(uop(0).roqIdx, uop(1).roqIdx), uop(1), uop(0)),
358      Mux(valid(0) && !valid(1), uop(0), uop(1)))
359  }
360
361  def getAfterMask(valid: Seq[Bool], uop: Seq[MicroOp]) = {
362    assert(valid.length == uop.length)
363    val length = valid.length
364    (0 until length).map(i => {
365      (0 until length).map(j => {
366        Mux(valid(i) && valid(j),
367          isAfter(uop(i).roqIdx, uop(j).roqIdx),
368          Mux(!valid(i), true.B, false.B))
369      })
370    })
371  }
372
373  def rangeMask(start: LqPtr, end: LqPtr): UInt = {
374    val startMask = (1.U((LoadQueueSize + 1).W) << start.value).asUInt - 1.U
375    val endMask = (1.U((LoadQueueSize + 1).W) << end.value).asUInt - 1.U
376    val xorMask = startMask(LoadQueueSize - 1, 0) ^ endMask(LoadQueueSize - 1, 0)
377    Mux(start.flag === end.flag, xorMask, ~xorMask)
378  }
379
380  // ignore data forward
381  (0 until LoadPipelineWidth).foreach(i => {
382    io.forward(i).forwardMask := DontCare
383    io.forward(i).forwardData := DontCare
384  })
385
386  // store backward query and rollback
387  def detectRollback(i: Int) = {
388    val startIndex = io.storeIn(i).bits.uop.lqIdx.value
389    val lqIdxMask = UIntToMask(startIndex, LoadQueueSize)
390    val xorMask = lqIdxMask ^ enqMask
391    val sameFlag = io.storeIn(i).bits.uop.lqIdx.flag === enqPtrExt.flag
392    val toEnqPtrMask = Mux(sameFlag, xorMask, ~xorMask)
393
394    // check if load already in lq needs to be rolledback
395    val lqViolationVec = RegNext(VecInit((0 until LoadQueueSize).map(j => {
396      val addrMatch = allocated(j) &&
397        io.storeIn(i).bits.paddr(PAddrBits - 1, 3) === dataModule.io.rdata(j).paddr(PAddrBits - 1, 3)
398      val entryNeedCheck = toEnqPtrMask(j) && addrMatch && (datavalid(j) || listening(j) || miss(j))
399      // TODO: update refilled data
400      val violationVec = (0 until 8).map(k => dataModule.io.rdata(j).mask(k) && io.storeIn(i).bits.mask(k))
401      Cat(violationVec).orR() && entryNeedCheck
402    })))
403    val lqViolation = lqViolationVec.asUInt().orR()
404    val lqViolationIndex = getFirstOne(lqViolationVec, RegNext(lqIdxMask))
405    val lqViolationUop = uop(lqViolationIndex)
406    // lqViolationUop.lqIdx.flag := deqMask(lqViolationIndex) ^ deqPtrExt.flag
407    // lqViolationUop.lqIdx.value := lqViolationIndex
408    XSDebug(lqViolation, p"${Binary(Cat(lqViolationVec))}, $startIndex, $lqViolationIndex\n")
409
410    // when l/s writeback to roq together, check if rollback is needed
411    val wbViolationVec = RegNext(VecInit((0 until LoadPipelineWidth).map(j => {
412      io.loadIn(j).valid &&
413        isAfter(io.loadIn(j).bits.uop.roqIdx, io.storeIn(i).bits.uop.roqIdx) &&
414        io.storeIn(i).bits.paddr(PAddrBits - 1, 3) === io.loadIn(j).bits.paddr(PAddrBits - 1, 3) &&
415        (io.storeIn(i).bits.mask & io.loadIn(j).bits.mask).orR
416    })))
417    val wbViolation = wbViolationVec.asUInt().orR()
418    val wbViolationUop = getOldestInTwo(wbViolationVec, RegNext(VecInit(io.loadIn.map(_.bits.uop))))
419    XSDebug(wbViolation, p"${Binary(Cat(wbViolationVec))}, $wbViolationUop\n")
420
421    // check if rollback is needed for load in l1
422    val l1ViolationVec = RegNext(VecInit((0 until LoadPipelineWidth).map(j => {
423      io.forward(j).valid && // L1 valid
424        isAfter(io.forward(j).uop.roqIdx, io.storeIn(i).bits.uop.roqIdx) &&
425        io.storeIn(i).bits.paddr(PAddrBits - 1, 3) === io.forward(j).paddr(PAddrBits - 1, 3) &&
426        (io.storeIn(i).bits.mask & io.forward(j).mask).orR
427    })))
428    val l1Violation = l1ViolationVec.asUInt().orR()
429    val l1ViolationUop = getOldestInTwo(l1ViolationVec, RegNext(VecInit(io.forward.map(_.uop))))
430    XSDebug(l1Violation, p"${Binary(Cat(l1ViolationVec))}, $l1ViolationUop\n")
431
432    val rollbackValidVec = Seq(lqViolation, wbViolation, l1Violation)
433    val rollbackUopVec = Seq(lqViolationUop, wbViolationUop, l1ViolationUop)
434
435    val mask = getAfterMask(rollbackValidVec, rollbackUopVec)
436    val oneAfterZero = mask(1)(0)
437    val rollbackUop = Mux(oneAfterZero && mask(2)(0),
438      rollbackUopVec(0),
439      Mux(!oneAfterZero && mask(2)(1), rollbackUopVec(1), rollbackUopVec(2)))
440
441    XSDebug(
442      l1Violation,
443      "need rollback (l4 load) pc %x roqidx %d target %x\n",
444      io.storeIn(i).bits.uop.cf.pc, io.storeIn(i).bits.uop.roqIdx.asUInt, l1ViolationUop.roqIdx.asUInt
445    )
446    XSDebug(
447      lqViolation,
448      "need rollback (ld wb before store) pc %x roqidx %d target %x\n",
449      io.storeIn(i).bits.uop.cf.pc, io.storeIn(i).bits.uop.roqIdx.asUInt, lqViolationUop.roqIdx.asUInt
450    )
451    XSDebug(
452      wbViolation,
453      "need rollback (ld/st wb together) pc %x roqidx %d target %x\n",
454      io.storeIn(i).bits.uop.cf.pc, io.storeIn(i).bits.uop.roqIdx.asUInt, wbViolationUop.roqIdx.asUInt
455    )
456
457    (RegNext(io.storeIn(i).valid) && Cat(rollbackValidVec).orR, rollbackUop)
458  }
459
460  // rollback check
461  val rollback = Wire(Vec(StorePipelineWidth, Valid(new MicroOp)))
462  for (i <- 0 until StorePipelineWidth) {
463    val detectedRollback = detectRollback(i)
464    rollback(i).valid := detectedRollback._1
465    rollback(i).bits := detectedRollback._2
466  }
467
468  def rollbackSel(a: Valid[MicroOp], b: Valid[MicroOp]): ValidIO[MicroOp] = {
469    Mux(
470      a.valid,
471      Mux(
472        b.valid,
473        Mux(isAfter(a.bits.roqIdx, b.bits.roqIdx), b, a), // a,b both valid, sel oldest
474        a // sel a
475      ),
476      b // sel b
477    )
478  }
479
480  val rollbackSelected = ParallelOperation(rollback, rollbackSel)
481  val lastCycleRedirect = RegNext(io.brqRedirect)
482
483  io.rollback := DontCare
484  // Note that we use roqIdx - 1.U to flush the load instruction itself.
485  // Thus, here if last cycle's roqIdx equals to this cycle's roqIdx, it still triggers the redirect.
486  io.rollback.valid := rollbackSelected.valid && (!lastCycleRedirect.valid || !isAfter(rollbackSelected.bits.roqIdx, lastCycleRedirect.bits.roqIdx))
487
488  io.rollback.bits.roqIdx := rollbackSelected.bits.roqIdx - 1.U
489  io.rollback.bits.isReplay := true.B
490  io.rollback.bits.isMisPred := false.B
491  io.rollback.bits.isException := false.B
492  io.rollback.bits.isFlushPipe := false.B
493  io.rollback.bits.target := rollbackSelected.bits.cf.pc
494  io.rollback.bits.brTag := rollbackSelected.bits.brTag
495
496  // Memory mapped IO / other uncached operations
497
498  // setup misc mem access req
499  // mask / paddr / data can be get from lq.data
500  val commitType = io.commits.uop(0).ctrl.commitType
501  io.uncache.req.valid := pending(deqPtr) && allocated(deqPtr) &&
502    commitType === CommitType.LOAD &&
503    io.roqDeqPtr === uop(deqPtr).roqIdx &&
504    !io.commits.isWalk
505
506  io.uncache.req.bits.cmd  := MemoryOpConstants.M_XRD
507  io.uncache.req.bits.addr := dataModule.io.rdata(deqPtr).paddr
508  io.uncache.req.bits.data := dataModule.io.rdata(deqPtr).data
509  io.uncache.req.bits.mask := dataModule.io.rdata(deqPtr).mask
510
511  io.uncache.req.bits.meta.id       := DontCare // TODO: // FIXME
512  io.uncache.req.bits.meta.vaddr    := DontCare
513  io.uncache.req.bits.meta.paddr    := dataModule.io.rdata(deqPtr).paddr
514  io.uncache.req.bits.meta.uop      := uop(deqPtr)
515  io.uncache.req.bits.meta.mmio     := true.B // dataModule.io.rdata(deqPtr).mmio
516  io.uncache.req.bits.meta.tlb_miss := false.B
517  io.uncache.req.bits.meta.mask     := dataModule.io.rdata(deqPtr).mask
518  io.uncache.req.bits.meta.replay   := false.B
519
520  io.uncache.resp.ready := true.B
521
522  when (io.uncache.req.fire()) {
523    pending(deqPtr) := false.B
524  }
525
526  dataModule.io.uncache.wen := false.B
527  when(io.uncache.resp.fire()){
528    datavalid(deqPtr) := true.B
529    dataModule.io.uncacheWrite(deqPtr, io.uncache.resp.bits.data(XLEN-1, 0))
530    dataModule.io.uncache.wen := true.B
531    // TODO: write back exception info
532  }
533
534  when(io.uncache.req.fire()){
535    XSDebug("uncache req: pc %x addr %x data %x op %x mask %x\n",
536      uop(deqPtr).cf.pc,
537      io.uncache.req.bits.addr,
538      io.uncache.req.bits.data,
539      io.uncache.req.bits.cmd,
540      io.uncache.req.bits.mask
541    )
542  }
543
544  when(io.uncache.resp.fire()){
545    XSDebug("uncache resp: data %x\n", io.dcache.resp.bits.data)
546  }
547
548  // Read vaddr for mem exception
549  io.exceptionAddr.vaddr := dataModule.io.rdata(io.exceptionAddr.lsIdx.lqIdx.value).vaddr
550
551  // misprediction recovery / exception redirect
552  // invalidate lq term using robIdx
553  val needCancel = Wire(Vec(LoadQueueSize, Bool()))
554  for (i <- 0 until LoadQueueSize) {
555    needCancel(i) := uop(i).roqIdx.needFlush(io.brqRedirect) && allocated(i) && !commited(i)
556    when(needCancel(i)) {
557      // when(io.brqRedirect.bits.isReplay){
558      //   valid(i) := false.B
559      //   writebacked(i) := false.B
560      //   listening(i) := false.B
561      //   miss(i) := false.B
562      //   pending(i) := false.B
563      // }.otherwise{
564        allocated(i) := false.B
565      // }
566    }
567  }
568  when (io.brqRedirect.valid && io.brqRedirect.bits.isMisPred) {
569    enqPtrExt := enqPtrExt - PopCount(needCancel)
570  }
571
572  // assert(!io.rollback.valid)
573  when(io.rollback.valid) {
574    XSDebug("Mem rollback: pc %x roqidx %d\n", io.rollback.bits.pc, io.rollback.bits.roqIdx.asUInt)
575  }
576
577  // debug info
578  XSDebug("head %d:%d tail %d:%d\n", enqPtrExt.flag, enqPtr, deqPtrExt.flag, deqPtr)
579
580  def PrintFlag(flag: Bool, name: String): Unit = {
581    when(flag) {
582      XSDebug(false, true.B, name)
583    }.otherwise {
584      XSDebug(false, true.B, " ")
585    }
586  }
587
588  for (i <- 0 until LoadQueueSize) {
589    if (i % 4 == 0) XSDebug("")
590    XSDebug(false, true.B, "%x [%x] ", uop(i).cf.pc, dataModule.io.rdata(i).paddr)
591    PrintFlag(allocated(i), "a")
592    PrintFlag(allocated(i) && datavalid(i), "v")
593    PrintFlag(allocated(i) && writebacked(i), "w")
594    PrintFlag(allocated(i) && commited(i), "c")
595    PrintFlag(allocated(i) && miss(i), "m")
596    PrintFlag(allocated(i) && listening(i), "l")
597    PrintFlag(allocated(i) && pending(i), "p")
598    XSDebug(false, true.B, " ")
599    if (i % 4 == 3 || i == LoadQueueSize - 1) XSDebug(false, true.B, "\n")
600  }
601
602}
603