xref: /XiangShan/src/main/scala/xiangshan/mem/lsqueue/LSQWrapper.scala (revision 556c96d6b6ae6e43d3fb87ddfd73967483e62a97)
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 org.chipsalliance.cde.config.Parameters
20import chisel3._
21import chisel3.util._
22import utils._
23import utility._
24import xiangshan._
25import xiangshan.backend.Bundles.{DynInst, MemExuOutput}
26import xiangshan.cache._
27import xiangshan.cache.{DCacheWordIO, DCacheLineIO, MemoryOpConstants}
28import xiangshan.cache.mmu.{TlbRequestIO, TlbHintIO}
29import xiangshan.mem._
30import xiangshan.backend._
31import xiangshan.backend.rob.RobLsqIO
32import coupledL2.{CMOReq, CMOResp}
33import xiangshan.backend.fu.FuType
34
35class ExceptionAddrIO(implicit p: Parameters) extends XSBundle {
36  val isStore = Input(Bool())
37  val vaddr = Output(UInt(VAddrBits.W))
38  val vstart = Output(UInt((log2Up(VLEN) + 1).W))
39  val vl = Output(UInt((log2Up(VLEN) + 1).W))
40  val gpaddr = Output(UInt(GPAddrBits.W))
41}
42
43class FwdEntry extends Bundle {
44  val validFast = Bool() // validFast is generated the same cycle with query
45  val valid = Bool() // valid is generated 1 cycle after query request
46  val data = UInt(8.W) // data is generated 1 cycle after query request
47}
48
49// inflight miss block reqs
50class InflightBlockInfo(implicit p: Parameters) extends XSBundle {
51  val block_addr = UInt(PAddrBits.W)
52  val valid = Bool()
53}
54
55class LsqEnqIO(implicit p: Parameters) extends MemBlockBundle {
56  val canAccept = Output(Bool())
57  val needAlloc = Vec(LSQEnqWidth, Input(UInt(2.W)))
58  val req       = Vec(LSQEnqWidth, Flipped(ValidIO(new DynInst)))
59  val iqAccept  = Input(Vec(LSQEnqWidth, Bool()))
60  val resp      = Vec(LSQEnqWidth, Output(new LSIdx))
61}
62
63// Load / Store Queue Wrapper for XiangShan Out of Order LSU
64class LsqWrapper(implicit p: Parameters) extends XSModule with HasDCacheParameters with HasPerfEvents {
65  val io = IO(new Bundle() {
66    val hartId = Input(UInt(hartIdLen.W))
67    val brqRedirect = Flipped(ValidIO(new Redirect))
68    val stvecFeedback = Vec(VecStorePipelineWidth, Flipped(ValidIO(new FeedbackToLsqIO)))
69    val ldvecFeedback = Vec(VecLoadPipelineWidth, Flipped(ValidIO(new FeedbackToLsqIO)))
70    val enq = new LsqEnqIO
71    val ldu = new Bundle() {
72        val stld_nuke_query = Vec(LoadPipelineWidth, Flipped(new LoadNukeQueryIO)) // from load_s2
73        val ldld_nuke_query = Vec(LoadPipelineWidth, Flipped(new LoadNukeQueryIO)) // from load_s2
74        val ldin = Vec(LoadPipelineWidth, Flipped(Decoupled(new LqWriteBundle))) // from load_s3
75    }
76    val sta = new Bundle() {
77      val storeMaskIn = Vec(StorePipelineWidth, Flipped(Valid(new StoreMaskBundle))) // from store_s0, store mask, send to sq from rs
78      val storeAddrIn = Vec(StorePipelineWidth, Flipped(Valid(new LsPipelineBundle))) // from store_s1
79      val storeAddrInRe = Vec(StorePipelineWidth, Input(new LsPipelineBundle())) // from store_s2
80    }
81    val std = new Bundle() {
82      val storeDataIn = Vec(StorePipelineWidth, Flipped(Valid(new MemExuOutput(isVector = true)))) // from store_s0, store data, send to sq from rs
83    }
84    val ldout = Vec(LoadPipelineWidth, DecoupledIO(new MemExuOutput))
85    val ld_raw_data = Vec(LoadPipelineWidth, Output(new LoadDataFromLQBundle))
86    val replay = Vec(LoadPipelineWidth, Decoupled(new LsPipelineBundle))
87    val sbuffer = Vec(EnsbufferWidth, Decoupled(new DCacheWordReqWithVaddrAndPfFlag))
88    val sbufferVecDifftestInfo = Vec(EnsbufferWidth, Decoupled(new DynInst)) // The vector store difftest needs is
89    val forward = Vec(LoadPipelineWidth, Flipped(new PipeLoadForwardQueryIO))
90    val rob = Flipped(new RobLsqIO)
91    val nuke_rollback = Vec(StorePipelineWidth, Output(Valid(new Redirect)))
92    val nack_rollback = Output(Valid(new Redirect))
93    val release = Flipped(Valid(new Release))
94   // val refill = Flipped(Valid(new Refill))
95    val tl_d_channel  = Input(new DcacheToLduForwardIO)
96    val maControl     = Flipped(new StoreMaBufToSqControlIO)
97    val uncacheOutstanding = Input(Bool())
98    val uncache = new UncacheWordIO
99    val mmioStout = DecoupledIO(new MemExuOutput) // writeback uncached store
100    // TODO: implement vector store
101    val vecmmioStout = DecoupledIO(new MemExuOutput(isVector = true)) // vec writeback uncached store
102    val sqEmpty = Output(Bool())
103    val lq_rep_full = Output(Bool())
104    val sqFull = Output(Bool())
105    val lqFull = Output(Bool())
106    val sqCancelCnt = Output(UInt(log2Up(StoreQueueSize+1).W))
107    val lqCancelCnt = Output(UInt(log2Up(VirtualLoadQueueSize+1).W))
108    val lqDeq = Output(UInt(log2Up(CommitWidth + 1).W))
109    val sqDeq = Output(UInt(log2Ceil(EnsbufferWidth + 1).W))
110    val lqCanAccept = Output(Bool())
111    val sqCanAccept = Output(Bool())
112    val lqDeqPtr = Output(new LqPtr)
113    val sqDeqPtr = Output(new SqPtr)
114    val exceptionAddr = new ExceptionAddrIO
115    val flushFrmMaBuf = Input(Bool())
116    val issuePtrExt = Output(new SqPtr)
117    val l2_hint = Input(Valid(new L2ToL1Hint()))
118    val tlb_hint = Flipped(new TlbHintIO)
119    val cmoOpReq  = DecoupledIO(new CMOReq)
120    val cmoOpResp = Flipped(DecoupledIO(new CMOResp))
121    val flushSbuffer = new SbufferFlushBundle
122    val force_write = Output(Bool())
123    val lqEmpty = Output(Bool())
124
125    // top-down
126    val debugTopDown = new LoadQueueTopDownIO
127  })
128
129  val loadQueue = Module(new LoadQueue)
130  val storeQueue = Module(new StoreQueue)
131
132  storeQueue.io.hartId := io.hartId
133  storeQueue.io.uncacheOutstanding := io.uncacheOutstanding
134
135
136  dontTouch(loadQueue.io.tlbReplayDelayCycleCtrl)
137  // Todo: imm
138  val tlbReplayDelayCycleCtrl = WireInit(VecInit(Seq(14.U(ReSelectLen.W), 0.U(ReSelectLen.W), 125.U(ReSelectLen.W), 0.U(ReSelectLen.W))))
139  loadQueue.io.tlbReplayDelayCycleCtrl := tlbReplayDelayCycleCtrl
140
141  // io.enq logic
142  // LSQ: send out canAccept when both load queue and store queue are ready
143  // Dispatch: send instructions to LSQ only when they are ready
144  io.enq.canAccept := loadQueue.io.enq.canAccept && storeQueue.io.enq.canAccept
145  io.lqCanAccept := loadQueue.io.enq.canAccept
146  io.sqCanAccept := storeQueue.io.enq.canAccept
147  loadQueue.io.enq.sqCanAccept := storeQueue.io.enq.canAccept
148  storeQueue.io.enq.lqCanAccept := loadQueue.io.enq.canAccept
149  io.lqDeqPtr := loadQueue.io.lqDeqPtr
150  io.sqDeqPtr := storeQueue.io.sqDeqPtr
151  for (i <- io.enq.req.indices) {
152    loadQueue.io.enq.needAlloc(i)      := io.enq.needAlloc(i)(0)
153    loadQueue.io.enq.req(i).valid      := io.enq.needAlloc(i)(0) && io.enq.req(i).valid
154    loadQueue.io.enq.req(i).bits       := io.enq.req(i).bits
155    loadQueue.io.enq.req(i).bits.sqIdx := storeQueue.io.enq.resp(i)
156
157    storeQueue.io.enq.needAlloc(i)      := io.enq.needAlloc(i)(1)
158    storeQueue.io.enq.req(i).valid      := io.enq.needAlloc(i)(1) && io.enq.req(i).valid
159    storeQueue.io.enq.req(i).bits       := io.enq.req(i).bits
160    storeQueue.io.enq.req(i).bits.lqIdx := loadQueue.io.enq.resp(i)
161
162    io.enq.resp(i).lqIdx := loadQueue.io.enq.resp(i)
163    io.enq.resp(i).sqIdx := storeQueue.io.enq.resp(i)
164  }
165
166  // store queue wiring
167  storeQueue.io.brqRedirect <> io.brqRedirect
168  storeQueue.io.vecFeedback   <> io.stvecFeedback
169  storeQueue.io.storeAddrIn <> io.sta.storeAddrIn // from store_s1
170  storeQueue.io.storeAddrInRe <> io.sta.storeAddrInRe // from store_s2
171  storeQueue.io.storeDataIn <> io.std.storeDataIn // from store_s0
172  storeQueue.io.storeMaskIn <> io.sta.storeMaskIn // from store_s0
173  storeQueue.io.sbuffer     <> io.sbuffer
174  storeQueue.io.sbufferVecDifftestInfo <> io.sbufferVecDifftestInfo
175  storeQueue.io.mmioStout   <> io.mmioStout
176  storeQueue.io.vecmmioStout <> io.vecmmioStout
177  storeQueue.io.rob         <> io.rob
178  storeQueue.io.exceptionAddr.isStore := DontCare
179  storeQueue.io.sqCancelCnt  <> io.sqCancelCnt
180  storeQueue.io.sqDeq        <> io.sqDeq
181  storeQueue.io.sqEmpty      <> io.sqEmpty
182  storeQueue.io.sqFull       <> io.sqFull
183  storeQueue.io.forward      <> io.forward // overlap forwardMask & forwardData, DO NOT CHANGE SEQUENCE
184  storeQueue.io.force_write  <> io.force_write
185  storeQueue.io.cmoOpReq     <> io.cmoOpReq
186  storeQueue.io.cmoOpResp    <> io.cmoOpResp
187  storeQueue.io.flushSbuffer <> io.flushSbuffer
188  storeQueue.io.maControl    <> io.maControl
189
190  /* <------- DANGEROUS: Don't change sequence here ! -------> */
191
192  //  load queue wiring
193  loadQueue.io.redirect            <> io.brqRedirect
194  loadQueue.io.vecFeedback           <> io.ldvecFeedback
195  loadQueue.io.ldu                 <> io.ldu
196  loadQueue.io.ldout               <> io.ldout
197  loadQueue.io.ld_raw_data         <> io.ld_raw_data
198  loadQueue.io.rob                 <> io.rob
199  loadQueue.io.nuke_rollback       <> io.nuke_rollback
200  loadQueue.io.nack_rollback       <> io.nack_rollback
201  loadQueue.io.replay              <> io.replay
202 // loadQueue.io.refill              <> io.refill
203  loadQueue.io.tl_d_channel        <> io.tl_d_channel
204  loadQueue.io.release             <> io.release
205  loadQueue.io.exceptionAddr.isStore := DontCare
206  loadQueue.io.flushFrmMaBuf       := io.flushFrmMaBuf
207  loadQueue.io.lqCancelCnt         <> io.lqCancelCnt
208  loadQueue.io.sq.stAddrReadySqPtr <> storeQueue.io.stAddrReadySqPtr
209  loadQueue.io.sq.stAddrReadyVec   <> storeQueue.io.stAddrReadyVec
210  loadQueue.io.sq.stDataReadySqPtr <> storeQueue.io.stDataReadySqPtr
211  loadQueue.io.sq.stDataReadyVec   <> storeQueue.io.stDataReadyVec
212  loadQueue.io.sq.stIssuePtr       <> storeQueue.io.stIssuePtr
213  loadQueue.io.sq.sqEmpty          <> storeQueue.io.sqEmpty
214  loadQueue.io.sta.storeAddrIn     <> io.sta.storeAddrIn // store_s1
215  loadQueue.io.std.storeDataIn     <> io.std.storeDataIn // store_s0
216  loadQueue.io.lqFull              <> io.lqFull
217  loadQueue.io.lq_rep_full         <> io.lq_rep_full
218  loadQueue.io.lqDeq               <> io.lqDeq
219  loadQueue.io.l2_hint             <> io.l2_hint
220  loadQueue.io.tlb_hint            <> io.tlb_hint
221  loadQueue.io.lqEmpty             <> io.lqEmpty
222
223  // rob commits for lsq is delayed for two cycles, which causes the delayed update for deqPtr in lq/sq
224  // s0: commit
225  // s1:               exception find
226  // s2:               exception triggered
227  // s3: ptr updated & new address
228  // address will be used at the next cycle after exception is triggered
229  io.exceptionAddr.vaddr := Mux(RegNext(io.exceptionAddr.isStore), storeQueue.io.exceptionAddr.vaddr, loadQueue.io.exceptionAddr.vaddr)
230  io.exceptionAddr.vstart := Mux(RegNext(io.exceptionAddr.isStore), storeQueue.io.exceptionAddr.vstart, loadQueue.io.exceptionAddr.vstart)
231  io.exceptionAddr.vl     := Mux(RegNext(io.exceptionAddr.isStore), storeQueue.io.exceptionAddr.vl, loadQueue.io.exceptionAddr.vl)
232  io.exceptionAddr.gpaddr := Mux(RegNext(io.exceptionAddr.isStore), storeQueue.io.exceptionAddr.gpaddr, loadQueue.io.exceptionAddr.gpaddr)
233  io.issuePtrExt := storeQueue.io.stAddrReadySqPtr
234
235  // naive uncache arbiter
236  val s_idle :: s_load :: s_store :: Nil = Enum(3)
237  val pendingstate = RegInit(s_idle)
238
239  switch(pendingstate){
240    is(s_idle){
241      when(io.uncache.req.fire){
242        pendingstate := Mux(loadQueue.io.uncache.req.valid, s_load,
243                          Mux(io.uncacheOutstanding, s_idle, s_store))
244      }
245    }
246    is(s_load){
247      when(io.uncache.resp.fire){
248        pendingstate := s_idle
249      }
250    }
251    is(s_store){
252      when(io.uncache.resp.fire){
253        pendingstate := s_idle
254      }
255    }
256  }
257
258  loadQueue.io.uncache := DontCare
259  storeQueue.io.uncache := DontCare
260  loadQueue.io.uncache.req.ready := false.B
261  storeQueue.io.uncache.req.ready := false.B
262  loadQueue.io.uncache.resp.valid := false.B
263  storeQueue.io.uncache.resp.valid := false.B
264  when(loadQueue.io.uncache.req.valid){
265    io.uncache.req <> loadQueue.io.uncache.req
266  }.otherwise{
267    io.uncache.req <> storeQueue.io.uncache.req
268  }
269  when (io.uncacheOutstanding) {
270    io.uncache.resp <> loadQueue.io.uncache.resp
271  } .otherwise {
272    when(pendingstate === s_load){
273      io.uncache.resp <> loadQueue.io.uncache.resp
274    }.otherwise{
275      io.uncache.resp <> storeQueue.io.uncache.resp
276    }
277  }
278
279  loadQueue.io.debugTopDown <> io.debugTopDown
280
281  assert(!(loadQueue.io.uncache.req.valid && storeQueue.io.uncache.req.valid))
282  assert(!(loadQueue.io.uncache.resp.valid && storeQueue.io.uncache.resp.valid))
283  when (!io.uncacheOutstanding) {
284    assert(!((loadQueue.io.uncache.resp.valid || storeQueue.io.uncache.resp.valid) && pendingstate === s_idle))
285  }
286
287
288  val perfEvents = Seq(loadQueue, storeQueue).flatMap(_.getPerfEvents)
289  generatePerfEvent()
290}
291
292class LsqEnqCtrl(implicit p: Parameters) extends XSModule
293  with HasVLSUParameters  {
294  val io = IO(new Bundle {
295    val redirect = Flipped(ValidIO(new Redirect))
296    // to dispatch
297    val enq = new LsqEnqIO
298    // from `memBlock.io.lqDeq
299    val lcommit = Input(UInt(log2Up(CommitWidth + 1).W))
300    // from `memBlock.io.sqDeq`
301    val scommit = Input(UInt(log2Ceil(EnsbufferWidth + 1).W))
302    // from/tp lsq
303    val lqCancelCnt = Input(UInt(log2Up(VirtualLoadQueueSize + 1).W))
304    val sqCancelCnt = Input(UInt(log2Up(StoreQueueSize + 1).W))
305    val lqFreeCount = Output(UInt(log2Up(VirtualLoadQueueSize + 1).W))
306    val sqFreeCount = Output(UInt(log2Up(StoreQueueSize + 1).W))
307    val enqLsq = Flipped(new LsqEnqIO)
308  })
309
310  val lqPtr = RegInit(0.U.asTypeOf(new LqPtr))
311  val sqPtr = RegInit(0.U.asTypeOf(new SqPtr))
312  val lqCounter = RegInit(VirtualLoadQueueSize.U(log2Up(VirtualLoadQueueSize + 1).W))
313  val sqCounter = RegInit(StoreQueueSize.U(log2Up(StoreQueueSize + 1).W))
314  val canAccept = RegInit(false.B)
315
316  val blockVec = io.enq.iqAccept.map(!_) :+ true.B
317  val numLsElem = io.enq.req.map(_.bits.numLsElem)
318  val needEnqLoadQueue = VecInit(io.enq.req.map(x => FuType.isLoad(x.bits.fuType) || FuType.isVNonsegLoad(x.bits.fuType)))
319  val needEnqStoreQueue = VecInit(io.enq.req.map(x => FuType.isStore(x.bits.fuType) || FuType.isVNonsegStore(x.bits.fuType)))
320  val loadQueueElem = needEnqLoadQueue.zip(numLsElem).map(x => Mux(x._1, x._2, 0.U))
321  val storeQueueElem = needEnqStoreQueue.zip(numLsElem).map(x => Mux(x._1, x._2, 0.U))
322  val loadFlowPopCount = 0.U +: loadQueueElem.zipWithIndex.map{ case (l, i) =>
323    loadQueueElem.take(i + 1).reduce(_ + _)
324  }
325  val storeFlowPopCount = 0.U +: storeQueueElem.zipWithIndex.map { case (s, i) =>
326    storeQueueElem.take(i + 1).reduce(_ + _)
327  }
328  val lqAllocNumber = PriorityMux(blockVec.zip(loadFlowPopCount))
329  val sqAllocNumber = PriorityMux(blockVec.zip(storeFlowPopCount))
330
331  io.lqFreeCount  := lqCounter
332  io.sqFreeCount  := sqCounter
333  // How to update ptr and counter:
334  // (1) by default, updated according to enq/commit
335  // (2) when redirect and dispatch queue is empty, update according to lsq
336  val t1_redirect = RegNext(io.redirect.valid)
337  val t2_redirect = RegNext(t1_redirect)
338  val t2_update = t2_redirect && !VecInit(io.enq.needAlloc.map(_.orR)).asUInt.orR
339  val t3_update = RegNext(t2_update)
340  val t3_lqCancelCnt = GatedRegNext(io.lqCancelCnt)
341  val t3_sqCancelCnt = GatedRegNext(io.sqCancelCnt)
342  when (t3_update) {
343    lqPtr := lqPtr - t3_lqCancelCnt
344    lqCounter := lqCounter + io.lcommit + t3_lqCancelCnt
345    sqPtr := sqPtr - t3_sqCancelCnt
346    sqCounter := sqCounter + io.scommit + t3_sqCancelCnt
347  }.elsewhen (!io.redirect.valid && io.enq.canAccept) {
348    lqPtr := lqPtr + lqAllocNumber
349    lqCounter := lqCounter + io.lcommit - lqAllocNumber
350    sqPtr := sqPtr + sqAllocNumber
351    sqCounter := sqCounter + io.scommit - sqAllocNumber
352  }.otherwise {
353    lqCounter := lqCounter + io.lcommit
354    sqCounter := sqCounter + io.scommit
355  }
356
357
358  //TODO MaxAllocate and width of lqOffset/sqOffset needs to be discussed
359  val lqMaxAllocate = LSQLdEnqWidth
360  val sqMaxAllocate = LSQStEnqWidth
361  val maxAllocate = lqMaxAllocate max sqMaxAllocate
362  val ldCanAccept = lqCounter >= lqAllocNumber +& lqMaxAllocate.U
363  val sqCanAccept = sqCounter >= sqAllocNumber +& sqMaxAllocate.U
364  // It is possible that t3_update and enq are true at the same clock cycle.
365  // For example, if redirect.valid lasts more than one clock cycle,
366  // after the last redirect, new instructions may enter but previously redirect has not been resolved (updated according to the cancel count from LSQ).
367  // To solve the issue easily, we block enqueue when t3_update, which is RegNext(t2_update).
368  io.enq.canAccept := RegNext(ldCanAccept && sqCanAccept && !t2_update)
369  val lqOffset = Wire(Vec(io.enq.resp.length, UInt(lqPtr.value.getWidth.W)))
370  val sqOffset = Wire(Vec(io.enq.resp.length, UInt(sqPtr.value.getWidth.W)))
371  for ((resp, i) <- io.enq.resp.zipWithIndex) {
372    lqOffset(i) := loadFlowPopCount(i)
373    resp.lqIdx := lqPtr + lqOffset(i)
374    sqOffset(i) := storeFlowPopCount(i)
375    resp.sqIdx := sqPtr + sqOffset(i)
376  }
377
378  io.enqLsq.needAlloc := RegNext(io.enq.needAlloc)
379  io.enqLsq.iqAccept := RegNext(io.enq.iqAccept)
380  io.enqLsq.req.zip(io.enq.req).zip(io.enq.resp).foreach{ case ((toLsq, enq), resp) =>
381    val do_enq = enq.valid && !io.redirect.valid && io.enq.canAccept
382    toLsq.valid := RegNext(do_enq)
383    toLsq.bits := RegEnable(enq.bits, do_enq)
384    toLsq.bits.lqIdx := RegEnable(resp.lqIdx, do_enq)
385    toLsq.bits.sqIdx := RegEnable(resp.sqIdx, do_enq)
386  }
387
388}