xref: /XiangShan/src/main/scala/xiangshan/mem/pipeline/HybridUnit.scala (revision ef18518e6467b7e2992e16d98a9cd3e64154de66)
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.ExceptionNO._
25import xiangshan._
26import xiangshan.backend.Bundles.{DynInst, MemExuInput, MemExuOutput}
27import xiangshan.backend.fu.PMPRespBundle
28import xiangshan.backend.fu.FuConfig._
29import xiangshan.backend.ctrlblock.{DebugLsInfoBundle, LsTopdownInfo}
30import xiangshan.backend.rob.RobPtr
31import xiangshan.backend.fu._
32import xiangshan.backend.fu.util.SdtrigExt
33import xiangshan.cache._
34import xiangshan.cache.wpu.ReplayCarry
35import xiangshan.cache.mmu.{TlbCmd, TlbReq, TlbRequestIO, TlbResp}
36import xiangshan.mem.mdp._
37
38class HybridUnit(implicit p: Parameters) extends XSModule
39  with HasLoadHelper
40  with HasPerfEvents
41  with HasDCacheParameters
42  with HasCircularQueuePtrHelper
43  with HasVLSUParameters
44  with SdtrigExt
45{
46  val io = IO(new Bundle() {
47    // control
48    val redirect      = Flipped(ValidIO(new Redirect))
49    val csrCtrl       = Flipped(new CustomCSRCtrlIO)
50
51    // flow in
52    val lsin          = Flipped(Decoupled(new MemExuInput))
53
54    // flow out
55    val ldout = DecoupledIO(new MemExuOutput)
56    val stout = DecoupledIO(new MemExuOutput)
57
58    val ldu_io = new Bundle() {
59      // dcache
60      val dcache        = new DCacheLoadIO
61
62      // data path
63      val sbuffer       = new LoadForwardQueryIO
64      val vec_forward   = new LoadForwardQueryIO
65      val lsq           = new LoadToLsqIO
66      val tl_d_channel  = Input(new DcacheToLduForwardIO)
67      val forward_mshr  = Flipped(new LduToMissqueueForwardIO)
68      val refill        = Flipped(ValidIO(new Refill))
69      val l2_hint       = Input(Valid(new L2ToL1Hint))
70
71      // fast wakeup
72      val fast_uop = ValidIO(new DynInst) // early wakeup signal generated in load_s1, send to RS in load_s2
73
74      // trigger
75      val trigger = Vec(TriggerNum, new LoadUnitTriggerIO)
76
77      // load to load fast path
78      val l2l_fwd_in    = Input(new LoadToLoadIO)
79      val l2l_fwd_out   = Output(new LoadToLoadIO)
80
81      val ld_fast_match    = Input(Bool())
82      val ld_fast_fuOpType = Input(UInt())
83      val ld_fast_imm      = Input(UInt(12.W))
84
85      // hardware prefetch to l1 cache req
86      val prefetch_req    = Flipped(ValidIO(new L1PrefetchReq))
87
88      // iq cancel
89      val ldCancel = Output(new LoadCancelIO()) // use to cancel the uops waked by this load, and cancel load
90
91      // load ecc error
92      val s3_dly_ld_err = Output(Bool()) // Note that io.s3_dly_ld_err and io.lsq.s3_dly_ld_err is different
93
94      // schedule error query
95      val stld_nuke_query = Flipped(Vec(StorePipelineWidth, Valid(new StoreNukeQueryIO)))
96
97      // queue-based replay
98      val replay       = Flipped(Decoupled(new LsPipelineBundle))
99      val lq_rep_full  = Input(Bool())
100
101      // misc
102      val s2_ptr_chasing = Output(Bool()) // provide right pc for hw prefetch
103
104      // Load fast replay path
105      val fast_rep_in  = Flipped(Decoupled(new LqWriteBundle))
106      val fast_rep_out = Decoupled(new LqWriteBundle)
107
108      // Load RAR rollback
109      val rollback = Valid(new Redirect)
110
111      // perf
112      val debug_ls         = Output(new DebugLsInfoBundle)
113      val lsTopdownInfo    = Output(new LsTopdownInfo)
114    }
115
116    val stu_io = new Bundle() {
117      val dcache          = new DCacheStoreIO
118      val prefetch_req    = Flipped(DecoupledIO(new StorePrefetchReq))
119      val issue           = Valid(new MemExuInput)
120      val lsq             = ValidIO(new LsPipelineBundle)
121      val lsq_replenish   = Output(new LsPipelineBundle())
122      val stld_nuke_query = Valid(new StoreNukeQueryIO)
123      val st_mask_out     = Valid(new StoreMaskBundle)
124      val debug_ls        = Output(new DebugLsInfoBundle)
125    }
126
127    val vec_stu_io = new Bundle() {
128      val in = Flipped(DecoupledIO(new VecStorePipeBundle()))
129      val isFirstIssue = Input(Bool())
130      val lsq = ValidIO(new LsPipelineBundle())
131      val feedbackSlow = ValidIO(new VSFQFeedback)
132    }
133
134    // prefetch
135    val prefetch_train            = ValidIO(new LdPrefetchTrainBundle()) // provide prefetch info to sms
136    val prefetch_train_l1         = ValidIO(new LdPrefetchTrainBundle()) // provide prefetch info to stream & stride
137    val canAcceptLowConfPrefetch  = Output(Bool())
138    val canAcceptHighConfPrefetch = Output(Bool())
139    val correctMissTrain          = Input(Bool())
140
141    // data path
142    val tlb           = new TlbRequestIO(2)
143    val pmp           = Flipped(new PMPRespBundle()) // arrive same to tlb now
144
145    // rs feedback
146    val feedback_fast = ValidIO(new RSFeedback) // stage 2
147    val feedback_slow = ValidIO(new RSFeedback) // stage 3
148  })
149
150  val StorePrefetchL1Enabled = EnableStorePrefetchAtCommit || EnableStorePrefetchAtIssue || EnableStorePrefetchSPB
151  val s1_ready, s2_ready, s3_ready, sx_can_go = WireInit(false.B)
152
153  // Pipeline
154  // --------------------------------------------------------------------------------
155  // stage 0
156  // --------------------------------------------------------------------------------
157  // generate addr, use addr to query DCache and DTLB
158  val s0_valid         = Wire(Bool())
159  val s0_dcache_ready  = Wire(Bool())
160  val s0_kill          = Wire(Bool())
161  val s0_vaddr         = Wire(UInt(VAddrBits.W))
162  val s0_mask          = Wire(UInt((VLEN/8).W))
163  val s0_uop           = Wire(new DynInst)
164  val s0_has_rob_entry = Wire(Bool())
165  val s0_rsIdx         = Wire(UInt(log2Up(MemIQSizeMax).W))
166  val s0_mshrid        = Wire(UInt())
167  val s0_try_l2l       = Wire(Bool())
168  val s0_rep_carry     = Wire(new ReplayCarry(nWays))
169  val s0_isFirstIssue  = Wire(Bool())
170  val s0_fast_rep      = Wire(Bool())
171  val s0_ld_rep        = Wire(Bool())
172  val s0_l2l_fwd       = Wire(Bool())
173  val s0_sched_idx     = Wire(UInt())
174  val s0_deqPortIdx    = Wire(UInt(log2Ceil(LoadPipelineWidth).W))
175  val s0_can_go        = s1_ready
176  val s0_fire          = s0_valid && s0_dcache_ready && s0_can_go
177  val s0_out           = Wire(new LqWriteBundle)
178  // vector
179  val s0_isvec = WireInit(false.B)
180  val s0_exp = WireInit(true.B)
181  val s0_flowPtr = WireInit(0.U.asTypeOf(new VsFlowPtr))
182
183  // load flow select/gen
184  // src0: super load replayed by LSQ (cache miss replay) (io.ldu_io.replay)
185  // src1: fast load replay (io.ldu_io.fast_rep_in)
186  // src2: load replayed by LSQ (io.ldu_io.replay)
187  // src3: hardware prefetch from prefetchor (high confidence) (io.prefetch)
188  // src4: int read / software prefetch first issue from RS (io.in)
189  // src5: vec read first issue from RS (TODO)
190  // src6: load try pointchaising when no issued or replayed load (io.fastpath)
191  // src7: hardware prefetch from prefetchor (high confidence) (io.prefetch)
192  // priority: high to low
193  val s0_ld_flow             = FuType.isLoad(s0_uop.fuType) || FuType.isVLoad(s0_uop.fuType)
194  val s0_rep_stall           = io.lsin.valid && isAfter(io.ldu_io.replay.bits.uop.robIdx, io.lsin.bits.uop.robIdx)
195  val s0_super_ld_rep_valid  = io.ldu_io.replay.valid && io.ldu_io.replay.bits.forward_tlDchannel
196  val s0_ld_fast_rep_valid   = io.ldu_io.fast_rep_in.valid
197  val s0_ld_rep_valid        = io.ldu_io.replay.valid && !io.ldu_io.replay.bits.forward_tlDchannel && !s0_rep_stall
198  val s0_high_conf_prf_valid = io.ldu_io.prefetch_req.valid && io.ldu_io.prefetch_req.bits.confidence > 0.U
199  val s0_int_iss_valid       = io.lsin.valid // int flow first issue or software prefetch
200  val s0_vec_iss_valid       = io.vec_stu_io.in.valid
201  val s0_l2l_fwd_valid       = io.ldu_io.l2l_fwd_in.valid && io.ldu_io.ld_fast_match
202  val s0_low_conf_prf_valid  = io.ldu_io.prefetch_req.valid && io.ldu_io.prefetch_req.bits.confidence === 0.U
203  dontTouch(s0_super_ld_rep_valid)
204  dontTouch(s0_ld_fast_rep_valid)
205  dontTouch(s0_ld_rep_valid)
206  dontTouch(s0_high_conf_prf_valid)
207  dontTouch(s0_int_iss_valid)
208  dontTouch(s0_vec_iss_valid)
209  dontTouch(s0_l2l_fwd_valid)
210  dontTouch(s0_low_conf_prf_valid)
211
212  // load flow source ready
213  val s0_super_ld_rep_ready  = WireInit(true.B)
214  val s0_ld_fast_rep_ready   = !s0_super_ld_rep_valid
215  val s0_ld_rep_ready        = !s0_super_ld_rep_valid &&
216                               !s0_ld_fast_rep_valid
217  val s0_high_conf_prf_ready = !s0_super_ld_rep_valid &&
218                               !s0_ld_fast_rep_valid &&
219                               !s0_ld_rep_valid
220
221  val s0_int_iss_ready       = !s0_super_ld_rep_valid &&
222                               !s0_ld_fast_rep_valid &&
223                               !s0_ld_rep_valid &&
224                               !s0_high_conf_prf_valid
225
226  val s0_vec_iss_ready       = !s0_super_ld_rep_valid &&
227                               !s0_ld_fast_rep_valid &&
228                               !s0_ld_rep_valid &&
229                               !s0_high_conf_prf_valid &&
230                               !s0_int_iss_valid
231
232  val s0_l2l_fwd_ready       = !s0_super_ld_rep_valid &&
233                               !s0_ld_fast_rep_valid &&
234                               !s0_ld_rep_valid &&
235                               !s0_high_conf_prf_valid &&
236                               !s0_int_iss_valid &&
237                               !s0_vec_iss_valid
238
239  val s0_low_conf_prf_ready  = !s0_super_ld_rep_valid &&
240                               !s0_ld_fast_rep_valid &&
241                               !s0_ld_rep_valid &&
242                               !s0_high_conf_prf_valid &&
243                               !s0_int_iss_valid &&
244                               !s0_vec_iss_valid &&
245                               !s0_l2l_fwd_valid
246  dontTouch(s0_super_ld_rep_ready)
247  dontTouch(s0_ld_fast_rep_ready)
248  dontTouch(s0_ld_rep_ready)
249  dontTouch(s0_high_conf_prf_ready)
250  dontTouch(s0_int_iss_ready)
251  dontTouch(s0_vec_iss_ready)
252  dontTouch(s0_l2l_fwd_ready)
253  dontTouch(s0_low_conf_prf_ready)
254
255  // load flow source select (OH)
256  val s0_super_ld_rep_select = s0_super_ld_rep_valid && s0_super_ld_rep_ready
257  val s0_ld_fast_rep_select  = s0_ld_fast_rep_valid && s0_ld_fast_rep_ready
258  val s0_ld_rep_select       = s0_ld_rep_valid && s0_ld_rep_ready
259  val s0_hw_prf_select       = s0_high_conf_prf_ready && s0_high_conf_prf_valid ||
260                               s0_low_conf_prf_ready && s0_low_conf_prf_valid
261  val s0_int_iss_select      = s0_int_iss_ready && s0_int_iss_valid
262  val s0_vec_iss_select      = s0_vec_iss_ready && s0_vec_iss_valid
263  val s0_l2l_fwd_select      = s0_l2l_fwd_ready && s0_l2l_fwd_valid
264  dontTouch(s0_super_ld_rep_select)
265  dontTouch(s0_ld_fast_rep_select)
266  dontTouch(s0_ld_rep_select)
267  dontTouch(s0_hw_prf_select)
268  dontTouch(s0_int_iss_select)
269  dontTouch(s0_vec_iss_select)
270  dontTouch(s0_l2l_fwd_select)
271
272  s0_valid := (s0_super_ld_rep_valid ||
273               s0_ld_fast_rep_valid ||
274               s0_ld_rep_valid ||
275               s0_high_conf_prf_valid ||
276               s0_int_iss_valid ||
277               s0_vec_iss_valid ||
278               s0_l2l_fwd_valid ||
279               s0_low_conf_prf_valid) && !s0_kill
280
281  // which is S0's out is ready and dcache is ready
282  val s0_try_ptr_chasing      = s0_l2l_fwd_select
283  val s0_do_try_ptr_chasing   = s0_try_ptr_chasing && s0_can_go && io.ldu_io.dcache.req.ready
284  val s0_ptr_chasing_vaddr    = io.ldu_io.l2l_fwd_in.data(5, 0) +& io.ldu_io.ld_fast_imm(5, 0)
285  val s0_ptr_chasing_canceled = WireInit(false.B)
286  s0_kill := s0_ptr_chasing_canceled || (s0_out.uop.robIdx.needFlush(io.redirect) && !s0_try_ptr_chasing)
287
288  // prefetch related ctrl signal
289  val s0_prf    = Wire(Bool())
290  val s0_prf_rd = Wire(Bool())
291  val s0_prf_wr = Wire(Bool())
292  val s0_hw_prf = s0_hw_prf_select
293
294  io.canAcceptLowConfPrefetch  := s0_low_conf_prf_ready
295  io.canAcceptHighConfPrefetch := s0_high_conf_prf_ready
296
297  if (StorePrefetchL1Enabled) {
298    s0_dcache_ready := Mux(s0_ld_flow, io.ldu_io.dcache.req.ready, io.stu_io.dcache.req.ready)
299  } else {
300    s0_dcache_ready := Mux(s0_ld_flow, io.ldu_io.dcache.req.ready, true.B)
301  }
302
303  // query DTLB
304  io.tlb.req.valid                   := s0_valid && s0_dcache_ready
305  io.tlb.req.bits.cmd                := Mux(s0_prf,
306                                         Mux(s0_prf_wr, TlbCmd.write, TlbCmd.read),
307                                         Mux(s0_ld_flow, TlbCmd.read, TlbCmd.write)
308                                       )
309  io.tlb.req.bits.vaddr              := Mux(s0_hw_prf_select, io.ldu_io.prefetch_req.bits.paddr, s0_vaddr)
310  io.tlb.req.bits.size               := Mux(s0_isvec, io.vec_stu_io.in.bits.alignedType, LSUOpType.size(s0_uop.fuOpType))
311  io.tlb.req.bits.kill               := s0_kill
312  io.tlb.req.bits.memidx.is_ld       := s0_ld_flow
313  io.tlb.req.bits.memidx.is_st       := !s0_ld_flow
314  io.tlb.req.bits.memidx.idx         := s0_uop.lqIdx.value
315  io.tlb.req.bits.debug.robIdx       := s0_uop.robIdx
316  io.tlb.req.bits.no_translate       := s0_hw_prf_select  // hw b.reqetch addr does not need to be translated
317  io.tlb.req.bits.debug.pc           := s0_uop.pc
318  io.tlb.req.bits.debug.isFirstIssue := s0_isFirstIssue
319
320  // query DCache
321  // for load
322  io.ldu_io.dcache.req.valid             := s0_valid && s0_dcache_ready && s0_ld_flow
323  io.ldu_io.dcache.req.bits.cmd          :=  Mux(s0_prf_rd, MemoryOpConstants.M_PFR,
324                                              Mux(s0_prf_wr, MemoryOpConstants.M_PFW, MemoryOpConstants.M_XRD))
325  io.ldu_io.dcache.req.bits.vaddr        := s0_vaddr
326  io.ldu_io.dcache.req.bits.mask         := s0_mask
327  io.ldu_io.dcache.req.bits.data         := DontCare
328  io.ldu_io.dcache.req.bits.isFirstIssue := s0_isFirstIssue
329  io.ldu_io.dcache.req.bits.instrtype    := Mux(s0_prf, DCACHE_PREFETCH_SOURCE.U, LOAD_SOURCE.U)
330  io.ldu_io.dcache.req.bits.debug_robIdx := s0_uop.robIdx.value
331  io.ldu_io.dcache.req.bits.replayCarry  := s0_rep_carry
332  io.ldu_io.dcache.req.bits.id           := DontCare // TODO: update cache meta
333  io.ldu_io.dcache.pf_source             := Mux(s0_hw_prf_select, io.ldu_io.prefetch_req.bits.pf_source.value, L1_HW_PREFETCH_NULL)
334
335  // for store
336  io.stu_io.dcache.req.valid             := s0_valid && s0_dcache_ready && !s0_ld_flow && !s0_prf
337  io.stu_io.dcache.req.bits.cmd          := MemoryOpConstants.M_PFW
338  io.stu_io.dcache.req.bits.vaddr        := s0_vaddr
339  io.stu_io.dcache.req.bits.instrtype    := Mux(s0_prf, DCACHE_PREFETCH_SOURCE.U, STORE_SOURCE.U)
340
341  // load flow priority mux
342  def fromNullSource() = {
343    s0_vaddr         := 0.U
344    s0_mask          := 0.U
345    s0_uop           := 0.U.asTypeOf(new DynInst)
346    s0_try_l2l       := false.B
347    s0_has_rob_entry := false.B
348    s0_rsIdx         := 0.U
349    s0_rep_carry     := 0.U.asTypeOf(s0_rep_carry.cloneType)
350    s0_mshrid        := 0.U
351    s0_isFirstIssue  := false.B
352    s0_fast_rep      := false.B
353    s0_ld_rep        := false.B
354    s0_l2l_fwd       := false.B
355    s0_prf           := false.B
356    s0_prf_rd        := false.B
357    s0_prf_wr        := false.B
358    s0_sched_idx     := 0.U
359    s0_deqPortIdx    := 0.U
360  }
361
362  def fromFastReplaySource(src: LqWriteBundle) = {
363    s0_vaddr         := src.vaddr
364    s0_mask          := src.mask
365    s0_uop           := src.uop
366    s0_try_l2l       := false.B
367    s0_has_rob_entry := src.hasROBEntry
368    s0_rep_carry     := src.rep_info.rep_carry
369    s0_mshrid        := src.rep_info.mshr_id
370    s0_rsIdx         := src.rsIdx
371    s0_isFirstIssue  := false.B
372    s0_fast_rep      := true.B
373    s0_ld_rep        := src.isLoadReplay
374    s0_l2l_fwd       := false.B
375    s0_prf           := LSUOpType.isPrefetch(src.uop.fuOpType)
376    s0_prf_rd        := src.uop.fuOpType === LSUOpType.prefetch_r
377    s0_prf_wr        := src.uop.fuOpType === LSUOpType.prefetch_w
378    s0_sched_idx     := src.schedIndex
379    s0_deqPortIdx    := src.deqPortIdx
380  }
381
382  def fromNormalReplaySource(src: LsPipelineBundle) = {
383    s0_vaddr         := src.vaddr
384    s0_mask          := genVWmask(src.vaddr, src.uop.fuOpType(1, 0))
385    s0_uop           := src.uop
386    s0_try_l2l       := false.B
387    s0_has_rob_entry := true.B
388    s0_rsIdx         := src.rsIdx
389    s0_rep_carry     := src.replayCarry
390    s0_mshrid        := src.mshrid
391    s0_isFirstIssue  := false.B
392    s0_fast_rep      := false.B
393    s0_ld_rep        := true.B
394    s0_l2l_fwd       := false.B
395    s0_prf           := LSUOpType.isPrefetch(src.uop.fuOpType)
396    s0_prf_rd        := src.uop.fuOpType === LSUOpType.prefetch_r
397    s0_prf_wr        := src.uop.fuOpType === LSUOpType.prefetch_w
398    s0_sched_idx     := src.schedIndex
399    s0_deqPortIdx    := src.deqPortIdx
400  }
401
402  def fromPrefetchSource(src: L1PrefetchReq) = {
403    s0_vaddr         := src.getVaddr()
404    s0_mask          := 0.U
405    s0_uop           := DontCare
406    s0_try_l2l       := false.B
407    s0_has_rob_entry := false.B
408    s0_rsIdx         := 0.U
409    s0_rep_carry     := 0.U.asTypeOf(s0_rep_carry.cloneType)
410    s0_mshrid        := 0.U
411    s0_isFirstIssue  := false.B
412    s0_fast_rep      := false.B
413    s0_ld_rep        := false.B
414    s0_l2l_fwd       := false.B
415    s0_prf           := true.B
416    s0_prf_rd        := !src.is_store
417    s0_prf_wr        := src.is_store
418    s0_sched_idx     := 0.U
419    s0_deqPortIdx    := 0.U
420  }
421
422  def fromIntIssueSource(src: MemExuInput) = {
423    s0_vaddr         := src.src(0) + SignExt(src.uop.imm(11, 0), VAddrBits)
424    s0_mask          := genVWmask(s0_vaddr, src.uop.fuOpType(1,0))
425    s0_uop           := src.uop
426    s0_try_l2l       := false.B
427    s0_has_rob_entry := true.B
428    s0_rsIdx         := src.iqIdx
429    s0_rep_carry     := 0.U.asTypeOf(s0_rep_carry.cloneType)
430    s0_mshrid        := 0.U
431    s0_isFirstIssue  := true.B
432    s0_fast_rep      := false.B
433    s0_ld_rep        := false.B
434    s0_l2l_fwd       := false.B
435    s0_prf           := LSUOpType.isPrefetch(src.uop.fuOpType)
436    s0_prf_rd        := src.uop.fuOpType === LSUOpType.prefetch_r
437    s0_prf_wr        := src.uop.fuOpType === LSUOpType.prefetch_w
438    s0_sched_idx     := 0.U
439    s0_deqPortIdx    := src.deqPortIdx
440  }
441
442  def fromVecIssueSource(src: VecStorePipeBundle) = {
443    // For now, vector port handles only vector store flows
444    s0_vaddr         := src.vaddr
445    s0_mask          := src.mask
446    s0_uop           := src.uop
447    s0_try_l2l       := false.B
448    s0_has_rob_entry := true.B
449    s0_rsIdx         := 0.U
450    s0_rep_carry     := 0.U.asTypeOf(s0_rep_carry.cloneType)
451    s0_mshrid        := 0.U
452    s0_isFirstIssue  := src.isFirstIssue
453    s0_fast_rep      := false.B
454    s0_ld_rep        := false.B
455    s0_l2l_fwd       := false.B
456    s0_prf           := false.B
457    s0_prf_rd        := false.B
458    s0_prf_wr        := false.B
459    s0_sched_idx     := 0.U
460
461    s0_isvec         := true.B
462    s0_exp           := io.vec_stu_io.in.bits.exp
463    s0_flowPtr       := io.vec_stu_io.in.bits.flowPtr
464    s0_deqPortIdx    := 0.U
465  }
466
467  def fromLoadToLoadSource(src: LoadToLoadIO) = {
468    s0_vaddr              := Cat(src.data(XLEN-1, 6), s0_ptr_chasing_vaddr(5,0))
469    s0_mask               := genVWmask(s0_vaddr, io.ldu_io.ld_fast_fuOpType(1, 0))
470    // When there's no valid instruction from RS and LSQ, we try the load-to-load forwarding.
471    // Assume the pointer chasing is always ld.
472    s0_uop.fuOpType  := io.ldu_io.ld_fast_fuOpType
473    s0_try_l2l            := true.B
474    // we dont care s0_isFirstIssue and s0_rsIdx and s0_sqIdx and s0_deqPortIdx in S0 when trying pointchasing
475    // because these signals will be updated in S1
476    s0_has_rob_entry      := false.B
477    s0_rsIdx              := 0.U
478    s0_mshrid             := 0.U
479    s0_rep_carry          := 0.U.asTypeOf(s0_rep_carry.cloneType)
480    s0_isFirstIssue       := true.B
481    s0_fast_rep           := false.B
482    s0_ld_rep             := false.B
483    s0_l2l_fwd            := true.B
484    s0_prf                := false.B
485    s0_prf_rd             := false.B
486    s0_prf_wr             := false.B
487    s0_sched_idx          := 0.U
488    s0_deqPortIdx         := 0.U
489  }
490
491  // set default
492  s0_uop := DontCare
493  when (s0_super_ld_rep_select)      { fromNormalReplaySource(io.ldu_io.replay.bits)     }
494  .elsewhen (s0_ld_fast_rep_select)  { fromFastReplaySource(io.ldu_io.fast_rep_in.bits)  }
495  .elsewhen (s0_ld_rep_select)       { fromNormalReplaySource(io.ldu_io.replay.bits)     }
496  .elsewhen (s0_hw_prf_select)       { fromPrefetchSource(io.ldu_io.prefetch_req.bits)   }
497  .elsewhen (s0_int_iss_select)      { fromIntIssueSource(io.lsin.bits)                  }
498  .elsewhen (s0_vec_iss_select)      { fromVecIssueSource(io.vec_stu_io.in.bits)         }
499  .otherwise {
500    if (EnableLoadToLoadForward) {
501      fromLoadToLoadSource(io.ldu_io.l2l_fwd_in)
502    } else {
503      fromNullSource()
504    }
505  }
506
507  // address align check
508  val s0_addr_aligned = LookupTree(Mux(s0_isvec, io.vec_stu_io.in.bits.alignedType, s0_uop.fuOpType(1, 0)), List(
509    "b00".U   -> true.B,                   //b
510    "b01".U   -> (s0_vaddr(0)    === 0.U), //h
511    "b10".U   -> (s0_vaddr(1, 0) === 0.U), //w
512    "b11".U   -> (s0_vaddr(2, 0) === 0.U)  //d
513  ))
514
515  // accept load flow if dcache ready (tlb is always ready)
516  // TODO: prefetch need writeback to loadQueueFlag
517  s0_out               := DontCare
518  s0_out.rsIdx         := s0_rsIdx
519  s0_out.vaddr         := s0_vaddr
520  s0_out.mask          := s0_mask
521  s0_out.uop           := s0_uop
522  s0_out.isFirstIssue  := s0_isFirstIssue
523  s0_out.hasROBEntry   := s0_has_rob_entry
524  s0_out.isPrefetch    := s0_prf
525  s0_out.isHWPrefetch  := s0_hw_prf
526  s0_out.isFastReplay  := s0_fast_rep
527  s0_out.isLoadReplay  := s0_ld_rep
528  s0_out.isFastPath    := s0_l2l_fwd
529  s0_out.mshrid        := s0_mshrid
530  s0_out.isvec         := s0_isvec
531  s0_out.exp           := s0_exp
532  s0_out.sflowPtr      := s0_flowPtr
533  s0_out.uop.exceptionVec(loadAddrMisaligned)  := !s0_addr_aligned && s0_ld_flow
534  s0_out.uop.exceptionVec(storeAddrMisaligned) := !s0_addr_aligned && !s0_ld_flow
535  s0_out.forward_tlDchannel := s0_super_ld_rep_select
536  when(io.tlb.req.valid && s0_isFirstIssue) {
537    s0_out.uop.debugInfo.tlbFirstReqTime := GTimer()
538  }.otherwise{
539    s0_out.uop.debugInfo.tlbFirstReqTime := s0_uop.debugInfo.tlbFirstReqTime
540  }
541  s0_out.schedIndex     := s0_sched_idx
542  s0_out.deqPortIdx     := s0_deqPortIdx
543
544  // load fast replay
545  io.ldu_io.fast_rep_in.ready := (s0_can_go && io.ldu_io.dcache.req.ready && s0_ld_fast_rep_ready)
546
547  // load flow source ready
548  // cache missed load has highest priority
549  // always accept cache missed load flow from load replay queue
550  io.ldu_io.replay.ready := (s0_can_go && io.ldu_io.dcache.req.ready && (s0_ld_rep_ready && !s0_rep_stall || s0_super_ld_rep_select))
551
552  // accept load flow from rs when:
553  // 1) there is no lsq-replayed load
554  // 2) there is no fast replayed load
555  // 3) there is no high confidence prefetch request
556  io.lsin.ready := (s0_can_go &&
557                    Mux(FuType.isLoad(io.lsin.bits.uop.fuType), io.ldu_io.dcache.req.ready,
558                    (if (StorePrefetchL1Enabled) io.stu_io.dcache.req.ready else true.B)) && s0_int_iss_ready)
559  io.vec_stu_io.in.ready := s0_can_go && io.ldu_io.dcache.req.ready && s0_vec_iss_ready
560
561
562  // for hw prefetch load flow feedback, to be added later
563  // io.prefetch_in.ready := s0_hw_prf_select
564
565  // dcache replacement extra info
566  // TODO: should prefetch load update replacement?
567  io.ldu_io.dcache.replacementUpdated := Mux(s0_ld_rep_select || s0_super_ld_rep_select, io.ldu_io.replay.bits.replacementUpdated, false.B)
568
569  io.stu_io.prefetch_req.ready := s1_ready && io.stu_io.dcache.req.ready && !io.lsin.valid
570
571  // load debug
572  XSDebug(io.ldu_io.dcache.req.fire && s0_ld_flow,
573    p"[DCACHE LOAD REQ] pc ${Hexadecimal(s0_uop.pc)}, vaddr ${Hexadecimal(s0_vaddr)}\n"
574  )
575  XSDebug(s0_valid && s0_ld_flow,
576    p"S0: pc ${Hexadecimal(s0_out.uop.pc)}, lqIdx ${Hexadecimal(s0_out.uop.lqIdx.asUInt)}, " +
577    p"vaddr ${Hexadecimal(s0_out.vaddr)}, mask ${Hexadecimal(s0_out.mask)}\n")
578
579  // store debug
580  XSDebug(io.stu_io.dcache.req.fire && !s0_ld_flow,
581    p"[DCACHE STORE REQ] pc ${Hexadecimal(s0_uop.pc)}, vaddr ${Hexadecimal(s0_vaddr)}\n"
582  )
583  XSDebug(s0_valid && !s0_ld_flow,
584    p"S0: pc ${Hexadecimal(s0_out.uop.pc)}, sqIdx ${Hexadecimal(s0_out.uop.sqIdx.asUInt)}, " +
585    p"vaddr ${Hexadecimal(s0_out.vaddr)}, mask ${Hexadecimal(s0_out.mask)}\n")
586
587
588  // Pipeline
589  // --------------------------------------------------------------------------------
590  // stage 1
591  // --------------------------------------------------------------------------------
592  // TLB resp (send paddr to dcache)
593  val s1_valid      = RegInit(false.B)
594  val s1_in         = Wire(new LqWriteBundle)
595  val s1_out        = Wire(new LqWriteBundle)
596  val s1_kill       = Wire(Bool())
597  val s1_can_go     = s2_ready
598  val s1_fire       = s1_valid && !s1_kill && s1_can_go
599  val s1_ld_flow    = RegNext(s0_ld_flow)
600  val s1_isvec      = RegEnable(s0_out.isvec, false.B, s0_fire)
601
602  s1_ready := !s1_valid || s1_kill || s2_ready
603  when (s0_fire) { s1_valid := true.B }
604  .elsewhen (s1_fire) { s1_valid := false.B }
605  .elsewhen (s1_kill) { s1_valid := false.B }
606  s1_in   := RegEnable(s0_out, s0_fire)
607
608  val s1_fast_rep_dly_err = RegNext(io.ldu_io.fast_rep_in.bits.delayedLoadError)
609  val s1_fast_rep_kill    = s1_fast_rep_dly_err && s1_in.isFastReplay
610  val s1_l2l_fwd_dly_err  = RegNext(io.ldu_io.l2l_fwd_in.dly_ld_err)
611  val s1_l2l_fwd_kill     = s1_l2l_fwd_dly_err && s1_in.isFastPath
612  val s1_late_kill        = s1_fast_rep_kill || s1_l2l_fwd_kill
613  val s1_vaddr_hi         = Wire(UInt())
614  val s1_vaddr_lo         = Wire(UInt())
615  val s1_vaddr            = Wire(UInt())
616  val s1_paddr_dup_lsu    = Wire(UInt())
617  val s1_paddr_dup_dcache = Wire(UInt())
618  val s1_ld_exception     = ExceptionNO.selectByFu(s1_out.uop.exceptionVec, LduCfg).asUInt.orR   // af & pf exception were modified below.
619  val s1_st_exception     = ExceptionNO.selectByFu(s1_out.uop.exceptionVec, StaCfg).asUInt.orR   // af & pf exception were modified below.
620  val s1_exception        = (s1_ld_flow && s1_ld_exception) || (!s1_ld_flow && s1_st_exception)
621  val s1_tlb_miss         = io.tlb.resp.bits.miss
622  val s1_prf              = s1_in.isPrefetch
623  val s1_hw_prf           = s1_in.isHWPrefetch
624  val s1_sw_prf           = s1_prf && !s1_hw_prf
625  val s1_tlb_memidx       = io.tlb.resp.bits.memidx
626
627  // mmio cbo decoder
628  val s1_mmio_cbo  = (s1_in.uop.fuOpType === LSUOpType.cbo_clean ||
629                      s1_in.uop.fuOpType === LSUOpType.cbo_flush ||
630                      s1_in.uop.fuOpType === LSUOpType.cbo_inval) && !s1_ld_flow && !s1_prf
631  val s1_mmio = s1_mmio_cbo
632
633  s1_vaddr_hi         := s1_in.vaddr(VAddrBits - 1, 6)
634  s1_vaddr_lo         := s1_in.vaddr(5, 0)
635  s1_vaddr            := Cat(s1_vaddr_hi, s1_vaddr_lo)
636  s1_paddr_dup_lsu    := io.tlb.resp.bits.paddr(0)
637  s1_paddr_dup_dcache := io.tlb.resp.bits.paddr(1)
638
639  when (s1_tlb_memidx.is_ld && io.tlb.resp.valid && !s1_tlb_miss &&
640        s1_tlb_memidx.idx === s1_in.uop.lqIdx.value && s1_ld_flow) {
641    // printf("Load idx = %d\n", s1_tlb_memidx.idx)
642    s1_out.uop.debugInfo.tlbRespTime := GTimer()
643  } .elsewhen(s1_tlb_memidx.is_st && io.tlb.resp.valid && !s1_tlb_miss &&
644              s1_tlb_memidx.idx === s1_out.uop.sqIdx.value && !s1_ld_flow) {
645    // printf("Store idx = %d\n", s1_tlb_memidx.idx)
646    s1_out.uop.debugInfo.tlbRespTime := GTimer()
647  }
648
649  io.tlb.req_kill   := s1_kill
650  io.tlb.resp.ready := true.B
651
652  io.ldu_io.dcache.s1_paddr_dup_lsu    <> s1_paddr_dup_lsu
653  io.ldu_io.dcache.s1_paddr_dup_dcache <> s1_paddr_dup_dcache
654  io.ldu_io.dcache.s1_kill             := s1_kill || s1_tlb_miss || s1_exception
655
656  // store to load forwarding
657  io.ldu_io.sbuffer.valid := s1_valid && !(s1_exception || s1_tlb_miss || s1_kill || s1_fast_rep_kill || s1_prf || !s1_ld_flow)
658  io.ldu_io.sbuffer.vaddr := s1_vaddr
659  io.ldu_io.sbuffer.paddr := s1_paddr_dup_lsu
660  io.ldu_io.sbuffer.uop   := s1_in.uop
661  io.ldu_io.sbuffer.sqIdx := s1_in.uop.sqIdx
662  io.ldu_io.sbuffer.mask  := s1_in.mask
663  io.ldu_io.sbuffer.pc    := s1_in.uop.pc // FIXME: remove it
664
665  io.ldu_io.vec_forward.valid := s1_valid && !(s1_exception || s1_tlb_miss || s1_kill || s1_fast_rep_kill || s1_prf || !s1_ld_flow)
666  io.ldu_io.vec_forward.vaddr := s1_vaddr
667  io.ldu_io.vec_forward.paddr := s1_paddr_dup_lsu
668  io.ldu_io.vec_forward.uop   := s1_in.uop
669  io.ldu_io.vec_forward.sqIdx := s1_in.uop.sqIdx
670  io.ldu_io.vec_forward.mask  := s1_in.mask
671  io.ldu_io.vec_forward.pc    := s1_in.uop.pc // FIXME: remove it
672
673  io.ldu_io.lsq.forward.valid     := s1_valid && !(s1_exception || s1_tlb_miss || s1_kill || s1_fast_rep_kill || s1_prf || !s1_ld_flow)
674  io.ldu_io.lsq.forward.vaddr     := s1_vaddr
675  io.ldu_io.lsq.forward.paddr     := s1_paddr_dup_lsu
676  io.ldu_io.lsq.forward.uop       := s1_in.uop
677  io.ldu_io.lsq.forward.sqIdx     := s1_in.uop.sqIdx
678  io.ldu_io.lsq.forward.sqIdxMask := 0.U
679  io.ldu_io.lsq.forward.mask      := s1_in.mask
680  io.ldu_io.lsq.forward.pc        := s1_in.uop.pc // FIXME: remove it
681
682  // st-ld violation query
683  val s1_nuke = VecInit((0 until StorePipelineWidth).map(w => {
684                       io.ldu_io.stld_nuke_query(w).valid && // query valid
685                       isAfter(s1_in.uop.robIdx, io.ldu_io.stld_nuke_query(w).bits.robIdx) && // older store
686                       // TODO: Fix me when vector instruction
687                       (s1_paddr_dup_lsu(PAddrBits-1, 3) === io.ldu_io.stld_nuke_query(w).bits.paddr(PAddrBits-1, 3)) && // paddr match
688                       (s1_in.mask & io.ldu_io.stld_nuke_query(w).bits.mask).orR // data mask contain
689                      })).asUInt.orR && !s1_tlb_miss && s1_ld_flow
690
691  s1_out                   := s1_in
692  s1_out.vaddr             := s1_vaddr
693  s1_out.paddr             := s1_paddr_dup_lsu
694  s1_out.tlbMiss           := s1_tlb_miss
695  s1_out.ptwBack           := io.tlb.resp.bits.ptwBack
696  s1_out.rsIdx             := s1_in.rsIdx
697  s1_out.rep_info.debug    := s1_in.uop.debugInfo
698  s1_out.rep_info.nuke     := s1_nuke && !s1_sw_prf
699  s1_out.lateKill          := s1_late_kill
700
701  when (s1_ld_flow) {
702    when (!s1_late_kill) {
703      // current ori test will cause the case of ldest == 0, below will be modifeid in the future.
704      // af & pf exception were modified
705      s1_out.uop.exceptionVec(loadPageFault)   := io.tlb.resp.bits.excp(0).pf.ld
706      s1_out.uop.exceptionVec(loadAccessFault) := io.tlb.resp.bits.excp(0).af.ld
707    } .otherwise {
708      s1_out.uop.exceptionVec(loadAddrMisaligned) := false.B
709      s1_out.uop.exceptionVec(loadAccessFault)    := s1_late_kill
710    }
711  } .otherwise {
712    s1_out.uop.exceptionVec(storePageFault)   := io.tlb.resp.bits.excp(0).pf.st
713    s1_out.uop.exceptionVec(storeAccessFault) := io.tlb.resp.bits.excp(0).af.st
714  }
715
716  // pointer chasing
717  val s1_try_ptr_chasing       = RegNext(s0_do_try_ptr_chasing, false.B)
718  val s1_ptr_chasing_vaddr     = RegEnable(s0_ptr_chasing_vaddr, s0_do_try_ptr_chasing)
719  val s1_fu_op_type_not_ld     = WireInit(false.B)
720  val s1_not_fast_match        = WireInit(false.B)
721  val s1_addr_mismatch         = WireInit(false.B)
722  val s1_addr_misaligned       = WireInit(false.B)
723  val s1_ptr_chasing_canceled  = WireInit(false.B)
724  val s1_cancel_ptr_chasing    = WireInit(false.B)
725
726  s1_kill := s1_late_kill ||
727             s1_cancel_ptr_chasing ||
728             s1_in.uop.robIdx.needFlush(io.redirect) ||
729             RegEnable(s0_kill, false.B, io.lsin.valid || io.ldu_io.replay.valid || io.ldu_io.l2l_fwd_in.valid || io.ldu_io.fast_rep_in.valid || io.vec_stu_io.in.valid)
730
731  if (EnableLoadToLoadForward) {
732    // Sometimes, we need to cancel the load-load forwarding.
733    // These can be put at S0 if timing is bad at S1.
734    // Case 0: CACHE_SET(base + offset) != CACHE_SET(base) (lowest 6-bit addition has an overflow)
735    s1_addr_mismatch      := s1_ptr_chasing_vaddr(6) || RegEnable(io.ldu_io.ld_fast_imm(11, 6).orR, s0_do_try_ptr_chasing)
736    // Case 1: the address is misaligned, kill s1
737    s1_addr_misaligned    := LookupTree(s1_in.uop.fuOpType(1, 0), List(
738                             "b00".U   -> false.B,                  //b
739                             "b01".U   -> (s1_vaddr(0)    =/= 0.U), //h
740                             "b10".U   -> (s1_vaddr(1, 0) =/= 0.U), //w
741                             "b11".U   -> (s1_vaddr(2, 0) =/= 0.U)  //d
742                          ))
743    // Case 2: this load-load uop is cancelled
744    s1_ptr_chasing_canceled := !io.lsin.valid || FuType.isStore(io.lsin.bits.uop.fuType)
745
746    when (s1_try_ptr_chasing) {
747      s1_cancel_ptr_chasing := s1_addr_mismatch || s1_addr_misaligned || s1_ptr_chasing_canceled
748
749      s1_in.uop           := io.lsin.bits.uop
750      s1_in.rsIdx         := io.lsin.bits.iqIdx
751      s1_in.isFirstIssue  := io.lsin.bits.isFirstIssue
752      s1_vaddr_lo         := s1_ptr_chasing_vaddr(5, 0)
753      s1_paddr_dup_lsu    := Cat(io.tlb.resp.bits.paddr(0)(PAddrBits - 1, 6), s1_vaddr_lo)
754      s1_paddr_dup_dcache := Cat(io.tlb.resp.bits.paddr(0)(PAddrBits - 1, 6), s1_vaddr_lo)
755
756      // recored tlb time when get the data to ensure the correctness of the latency calculation (although it should not record in here, because it does not use tlb)
757      s1_in.uop.debugInfo.tlbFirstReqTime := GTimer()
758      s1_in.uop.debugInfo.tlbRespTime     := GTimer()
759    }
760    when (!s1_cancel_ptr_chasing) {
761      s0_ptr_chasing_canceled := s1_try_ptr_chasing && !io.ldu_io.replay.fire && !io.ldu_io.fast_rep_in.fire
762      when (s1_try_ptr_chasing) {
763        io.lsin.ready := true.B
764      }
765    }
766  }
767
768  // pre-calcuate sqIdx mask in s0, then send it to lsq in s1 for forwarding
769  val s1_sqIdx_mask = RegNext(UIntToMask(s0_out.uop.sqIdx.value, StoreQueueSize))
770  // to enable load-load, sqIdxMask must be calculated based on lsin.uop
771  // If the timing here is not OK, load-load forwarding has to be disabled.
772  // Or we calculate sqIdxMask at RS??
773  io.ldu_io.lsq.forward.sqIdxMask := s1_sqIdx_mask
774  if (EnableLoadToLoadForward) {
775    when (s1_try_ptr_chasing) {
776      io.ldu_io.lsq.forward.sqIdxMask := UIntToMask(io.lsin.bits.uop.sqIdx.value, StoreQueueSize)
777    }
778  }
779
780  io.ldu_io.forward_mshr.valid  := s1_valid && s1_out.forward_tlDchannel && s1_ld_flow
781  io.ldu_io.forward_mshr.mshrid := s1_out.mshrid
782  io.ldu_io.forward_mshr.paddr  := s1_out.paddr
783
784  io.stu_io.dcache.s1_kill := s1_tlb_miss || s1_exception || s1_mmio || s1_in.uop.robIdx.needFlush(io.redirect)
785  io.stu_io.dcache.s1_paddr := s1_paddr_dup_dcache
786
787
788  // load debug
789  XSDebug(s1_valid && s1_ld_flow,
790    p"S1: pc ${Hexadecimal(s1_out.uop.pc)}, lId ${Hexadecimal(s1_out.uop.lqIdx.asUInt)}, tlb_miss ${io.tlb.resp.bits.miss}, " +
791    p"paddr ${Hexadecimal(s1_out.paddr)}, mmio ${s1_out.mmio}\n")
792
793  // store debug
794  XSDebug(s1_valid && !s1_ld_flow,
795    p"S1: pc ${Hexadecimal(s1_out.uop.pc)}, lId ${Hexadecimal(s1_out.uop.sqIdx.asUInt)}, tlb_miss ${io.tlb.resp.bits.miss}, " +
796    p"paddr ${Hexadecimal(s1_out.paddr)}, mmio ${s1_out.mmio}\n")
797
798  // store out
799  io.stu_io.lsq.valid         := s1_valid && !s1_ld_flow && !s1_prf && !s1_isvec
800  io.stu_io.lsq.bits          := s1_out
801  io.stu_io.lsq.bits.miss     := s1_tlb_miss
802
803  io.vec_stu_io.lsq.valid     := s1_valid && !s1_ld_flow && !s1_prf && s1_isvec
804  io.vec_stu_io.lsq.bits          := s1_out
805  io.vec_stu_io.lsq.bits.miss     := s1_tlb_miss
806
807  io.stu_io.st_mask_out.valid       := s1_valid && !s1_ld_flow && !s1_prf
808  io.stu_io.st_mask_out.bits.mask   := s1_out.mask
809  io.stu_io.st_mask_out.bits.sqIdx  := s1_out.uop.sqIdx
810
811  io.stu_io.issue.valid       := s1_valid && !s1_tlb_miss && !s1_ld_flow && !s1_prf && !s1_isvec
812  io.stu_io.issue.bits        := RegEnable(io.lsin.bits, io.lsin.fire)
813
814  // st-ld violation dectect request
815  io.stu_io.stld_nuke_query.valid       := s1_valid && !s1_tlb_miss && !s1_ld_flow && !s1_prf
816  io.stu_io.stld_nuke_query.bits.robIdx := s1_in.uop.robIdx
817  io.stu_io.stld_nuke_query.bits.paddr  := s1_paddr_dup_lsu
818  io.stu_io.stld_nuke_query.bits.mask   := s1_in.mask
819
820  // Pipeline
821  // --------------------------------------------------------------------------------
822  // stage 2
823  // --------------------------------------------------------------------------------
824  // s2: DCache resp
825  val s2_valid  = RegInit(false.B)
826  val s2_in     = Wire(new LqWriteBundle)
827  val s2_out    = Wire(new LqWriteBundle)
828  val s2_kill   = Wire(Bool())
829  val s2_can_go = s3_ready
830  val s2_fire   = s2_valid && !s2_kill && s2_can_go
831  val s2_isvec  = RegEnable(s1_isvec, false.B, s1_fire)
832  val s2_exp    = RegEnable(s1_out.exp, true.B, s1_fire)
833  val s2_paddr  = RegEnable(s1_paddr_dup_lsu, s1_fire)
834
835  s2_kill := s2_in.uop.robIdx.needFlush(io.redirect)
836  s2_ready := !s2_valid || s2_kill || s3_ready
837  when (s1_fire) { s2_valid := true.B }
838  .elsewhen (s2_fire) { s2_valid := false.B }
839  .elsewhen (s2_kill) { s2_valid := false.B }
840  s2_in := RegEnable(s1_out, s1_fire)
841
842  val s2_pmp = WireInit(io.pmp)
843
844  val s2_prf    = s2_in.isPrefetch
845  val s2_hw_prf = s2_in.isHWPrefetch
846  val s2_ld_flow  = RegEnable(s1_ld_flow, s1_fire)
847
848  // exception that may cause load addr to be invalid / illegal
849  // if such exception happen, that inst and its exception info
850  // will be force writebacked to rob
851  val s2_exception_vec = WireInit(s2_in.uop.exceptionVec)
852  when (s2_ld_flow) {
853    when (!s2_in.lateKill) {
854      s2_exception_vec(loadAccessFault) := (s2_in.uop.exceptionVec(loadAccessFault) || s2_pmp.ld) && s2_exp
855      // soft prefetch will not trigger any exception (but ecc error interrupt may be triggered)
856      when (s2_prf || s2_in.tlbMiss) {
857        s2_exception_vec := 0.U.asTypeOf(s2_exception_vec.cloneType)
858      }
859    }
860  } .otherwise {
861    s2_exception_vec(storeAccessFault) := s2_in.uop.exceptionVec(storeAccessFault) || s2_pmp.st
862    when (s2_prf || s2_in.tlbMiss) {
863      s2_exception_vec := 0.U.asTypeOf(s2_exception_vec.cloneType)
864    }
865  }
866  val s2_ld_exception = ExceptionNO.selectByFu(s2_exception_vec, LduCfg).asUInt.orR && s2_ld_flow
867  val s2_st_exception = ExceptionNO.selectByFu(s2_exception_vec, StaCfg).asUInt.orR && !s2_ld_flow
868  val s2_exception    = s2_ld_exception || s2_st_exception
869
870  val (s2_fwd_frm_d_chan, s2_fwd_data_frm_d_chan) = io.ldu_io.tl_d_channel.forward(s1_valid && s1_out.forward_tlDchannel, s1_out.mshrid, s1_out.paddr)
871  val (s2_fwd_data_valid, s2_fwd_frm_mshr, s2_fwd_data_frm_mshr) = io.ldu_io.forward_mshr.forward()
872  val s2_fwd_frm_d_chan_or_mshr = s2_fwd_data_valid && (s2_fwd_frm_d_chan || s2_fwd_frm_mshr)
873
874  // writeback access fault caused by ecc error / bus error
875  // * ecc data error is slow to generate, so we will not use it until load stage 3
876  // * in load stage 3, an extra signal io.load_error will be used to
877  val s2_actually_mmio = s2_pmp.mmio
878  val s2_ld_mmio       = !s2_prf &&
879                          s2_actually_mmio &&
880                         !s2_exception &&
881                         !s2_in.tlbMiss &&
882                         s2_ld_flow
883  val s2_st_mmio       = !s2_prf &&
884                          (RegNext(s1_mmio) || s2_pmp.mmio) &&
885                         !s2_exception &&
886                         !s2_in.tlbMiss &&
887                         !s2_ld_flow
888  val s2_st_atomic     = !s2_prf &&
889                          (RegNext(s1_mmio) || s2_pmp.atomic) &&
890                         !s2_exception &&
891                         !s2_in.tlbMiss &&
892                         !s2_ld_flow
893  val s2_full_fwd      = Wire(Bool())
894  val s2_mem_amb       = s2_in.uop.storeSetHit &&
895                         io.ldu_io.lsq.forward.addrInvalid
896
897  val s2_tlb_miss      = s2_in.tlbMiss
898  val s2_fwd_fail      = io.ldu_io.lsq.forward.dataInvalid || io.ldu_io.vec_forward.dataInvalid
899  val s2_dcache_miss   = io.ldu_io.dcache.resp.bits.miss &&
900                         !s2_fwd_frm_d_chan_or_mshr &&
901                         !s2_full_fwd
902
903  val s2_mq_nack       = io.ldu_io.dcache.s2_mq_nack &&
904                         !s2_fwd_frm_d_chan_or_mshr &&
905                         !s2_full_fwd
906
907  val s2_bank_conflict = io.ldu_io.dcache.s2_bank_conflict &&
908                         !s2_fwd_frm_d_chan_or_mshr &&
909                         !s2_full_fwd
910
911  val s2_wpu_pred_fail = io.ldu_io.dcache.s2_wpu_pred_fail &&
912                        !s2_fwd_frm_d_chan_or_mshr &&
913                        !s2_full_fwd
914
915  val s2_rar_nack      = io.ldu_io.lsq.ldld_nuke_query.req.valid &&
916                         !io.ldu_io.lsq.ldld_nuke_query.req.ready
917
918  val s2_raw_nack      = io.ldu_io.lsq.stld_nuke_query.req.valid &&
919                         !io.ldu_io.lsq.stld_nuke_query.req.ready
920
921  // st-ld violation query
922  //  NeedFastRecovery Valid when
923  //  1. Fast recovery query request Valid.
924  //  2. Load instruction is younger than requestors(store instructions).
925  //  3. Physical address match.
926  //  4. Data contains.
927  val s2_nuke = VecInit((0 until StorePipelineWidth).map(w => {
928                        io.ldu_io.stld_nuke_query(w).valid && // query valid
929                        isAfter(s2_in.uop.robIdx, io.ldu_io.stld_nuke_query(w).bits.robIdx) && // older store
930                        // TODO: Fix me when vector instruction
931                        (s2_in.paddr(PAddrBits-1, 3) === io.ldu_io.stld_nuke_query(w).bits.paddr(PAddrBits-1, 3)) && // paddr match
932                        (s2_in.mask & io.ldu_io.stld_nuke_query(w).bits.mask).orR // data mask contain
933                      })).asUInt.orR && s2_ld_flow || s2_in.rep_info.nuke
934
935  val s2_cache_handled   = io.ldu_io.dcache.resp.bits.handled
936  val s2_cache_tag_error = RegNext(io.csrCtrl.cache_error_enable) &&
937                           io.ldu_io.dcache.resp.bits.tag_error
938
939  val s2_troublem        = !s2_exception &&
940                           !s2_ld_mmio &&
941                           !s2_prf &&
942                           !s2_in.lateKill &&
943                           s2_ld_flow
944
945  io.ldu_io.dcache.resp.ready := true.B
946  io.stu_io.dcache.resp.ready := true.B
947  val s2_dcache_should_resp = !(s2_in.tlbMiss || s2_exception || s2_ld_mmio || s2_prf || s2_in.lateKill) && s2_ld_flow
948  assert(!(s2_valid && (s2_dcache_should_resp && !io.ldu_io.dcache.resp.valid)), "DCache response got lost")
949
950  // fast replay require
951  val s2_dcache_fast_rep = (s2_mq_nack || !s2_dcache_miss && (s2_bank_conflict || s2_wpu_pred_fail))
952  val s2_nuke_fast_rep   = !s2_mq_nack &&
953                           !s2_dcache_miss &&
954                           !s2_bank_conflict &&
955                           !s2_wpu_pred_fail &&
956                           !s2_rar_nack &&
957                           !s2_raw_nack &&
958                           s2_nuke
959
960  val s2_fast_rep = !s2_mem_amb &&
961                    !s2_tlb_miss &&
962                    !s2_fwd_fail &&
963                    (s2_dcache_fast_rep || s2_nuke_fast_rep) &&
964                    s2_troublem
965
966  // need allocate new entry
967  val s2_can_query = !s2_mem_amb &&
968                     !s2_tlb_miss  &&
969                     !s2_fwd_fail &&
970                     !s2_dcache_fast_rep &&
971                     s2_troublem
972
973  val s2_data_fwded = s2_dcache_miss && (s2_full_fwd || s2_cache_tag_error)
974
975  // ld-ld violation require
976  io.ldu_io.lsq.ldld_nuke_query.req.valid           := s2_valid && s2_can_query
977  io.ldu_io.lsq.ldld_nuke_query.req.bits.uop        := s2_in.uop
978  io.ldu_io.lsq.ldld_nuke_query.req.bits.mask       := s2_in.mask
979  io.ldu_io.lsq.ldld_nuke_query.req.bits.paddr      := s2_in.paddr
980  io.ldu_io.lsq.ldld_nuke_query.req.bits.data_valid := Mux(s2_full_fwd || s2_fwd_data_valid, true.B, !s2_dcache_miss)
981
982  // st-ld violation require
983  io.ldu_io.lsq.stld_nuke_query.req.valid           := s2_valid && s2_can_query
984  io.ldu_io.lsq.stld_nuke_query.req.bits.uop        := s2_in.uop
985  io.ldu_io.lsq.stld_nuke_query.req.bits.mask       := s2_in.mask
986  io.ldu_io.lsq.stld_nuke_query.req.bits.paddr      := s2_in.paddr
987  io.ldu_io.lsq.stld_nuke_query.req.bits.data_valid := Mux(s2_full_fwd || s2_fwd_data_valid, true.B, !s2_dcache_miss)
988
989  // merge forward result
990  // lsq has higher priority than sbuffer
991  val s2_fwd_mask = Wire(Vec((VLEN/8), Bool()))
992  val s2_fwd_data = Wire(Vec((VLEN/8), UInt(8.W)))
993  s2_full_fwd := ((~s2_fwd_mask.asUInt).asUInt & s2_in.mask) === 0.U && !io.ldu_io.lsq.forward.dataInvalid && !io.ldu_io.vec_forward.dataInvalid
994  // generate XLEN/8 Muxs
995  for (i <- 0 until VLEN / 8) {
996    s2_fwd_mask(i) := io.ldu_io.lsq.forward.forwardMask(i) || io.ldu_io.sbuffer.forwardMask(i) || io.ldu_io.vec_forward.forwardMask(i)
997    s2_fwd_data(i) := Mux(
998      io.ldu_io.lsq.forward.forwardMask(i),
999      io.ldu_io.lsq.forward.forwardData(i),
1000      Mux(
1001        io.ldu_io.vec_forward.forwardMask(i),
1002        io.ldu_io.vec_forward.forwardData(i),
1003        io.ldu_io.sbuffer.forwardData(i)
1004      )
1005    )
1006  }
1007
1008  XSDebug(s2_fire && s2_ld_flow, "[FWD LOAD RESP] pc %x fwd %x(%b) + %x(%b)\n",
1009    s2_in.uop.pc,
1010    io.ldu_io.lsq.forward.forwardData.asUInt, io.ldu_io.lsq.forward.forwardMask.asUInt,
1011    s2_in.forwardData.asUInt, s2_in.forwardMask.asUInt
1012  )
1013
1014  //
1015  s2_out                  := s2_in
1016  s2_out.data             := 0.U // data will be generated in load s3
1017  s2_out.uop.fpWen        := s2_in.uop.fpWen && !s2_exception && s2_ld_flow
1018  s2_out.mmio             := s2_ld_mmio || s2_st_mmio
1019  s2_out.atomic           := s2_st_atomic
1020  s2_out.uop.flushPipe    := false.B
1021  s2_out.uop.exceptionVec := s2_exception_vec
1022  s2_out.forwardMask      := s2_fwd_mask
1023  s2_out.forwardData      := s2_fwd_data
1024  s2_out.handledByMSHR    := s2_cache_handled
1025  s2_out.miss             := s2_dcache_miss && s2_troublem
1026  s2_out.feedbacked       := io.feedback_fast.valid && !io.feedback_fast.bits.hit
1027
1028  // Generate replay signal caused by:
1029  // * st-ld violation check
1030  // * tlb miss
1031  // * dcache replay
1032  // * forward data invalid
1033  // * dcache miss
1034  s2_out.rep_info.mem_amb         := s2_mem_amb && s2_troublem
1035  s2_out.rep_info.tlb_miss        := s2_tlb_miss && s2_troublem
1036  s2_out.rep_info.fwd_fail        := s2_fwd_fail && s2_troublem
1037  s2_out.rep_info.dcache_rep      := s2_mq_nack && s2_troublem
1038  s2_out.rep_info.dcache_miss     := s2_dcache_miss && s2_troublem
1039  s2_out.rep_info.bank_conflict   := s2_bank_conflict && s2_troublem
1040  s2_out.rep_info.wpu_fail        := s2_wpu_pred_fail && s2_troublem
1041  s2_out.rep_info.rar_nack        := s2_rar_nack && s2_troublem
1042  s2_out.rep_info.raw_nack        := s2_raw_nack && s2_troublem
1043  s2_out.rep_info.nuke            := s2_nuke && s2_troublem
1044  s2_out.rep_info.full_fwd        := s2_data_fwded
1045  s2_out.rep_info.data_inv_sq_idx := Mux(io.ldu_io.vec_forward.dataInvalid, s2_out.uop.sqIdx, io.ldu_io.lsq.forward.dataInvalidSqIdx)
1046  s2_out.rep_info.addr_inv_sq_idx := Mux(io.ldu_io.vec_forward.addrInvalid, s2_out.uop.sqIdx, io.ldu_io.lsq.forward.addrInvalidSqIdx)
1047  s2_out.rep_info.rep_carry       := io.ldu_io.dcache.resp.bits.replayCarry
1048  s2_out.rep_info.mshr_id         := io.ldu_io.dcache.resp.bits.mshr_id
1049  s2_out.rep_info.last_beat       := s2_in.paddr(log2Up(refillBytes))
1050  s2_out.rep_info.debug           := s2_in.uop.debugInfo
1051
1052  // if forward fail, replay this inst from fetch
1053  val debug_fwd_fail_rep = s2_fwd_fail && !s2_troublem && !s2_in.tlbMiss
1054  // if ld-ld violation is detected, replay from this inst from fetch
1055  val debug_ldld_nuke_rep = false.B // s2_ldld_violation && !s2_ld_mmio && !s2_is_prefetch && !s2_in.tlbMiss
1056  // io.out.bits.uop.replayInst := false.B
1057
1058  // to be removed
1059  val s2_ld_need_fb = !s2_in.isLoadReplay &&      // already feedbacked
1060                      io.ldu_io.lq_rep_full &&           // LoadQueueReplay is full
1061                      s2_out.rep_info.need_rep && // need replay
1062                      !s2_exception &&            // no exception is triggered
1063                      !s2_hw_prf &&               // not hardware prefetch
1064                      !s2_isvec
1065  val s2_st_need_fb = !s2_ld_flow && !s2_hw_prf && !s2_isvec
1066  io.feedback_fast.valid                 := s2_valid && (s2_ld_need_fb || s2_st_need_fb)
1067  io.feedback_fast.bits.hit              := Mux(s2_ld_flow, false.B, !s2_tlb_miss)
1068  io.feedback_fast.bits.flushState       := s2_in.ptwBack
1069  io.feedback_fast.bits.robIdx           := s2_in.uop.robIdx
1070  io.feedback_fast.bits.sourceType       := Mux(s2_ld_flow, RSFeedbackType.lrqFull, RSFeedbackType.tlbMiss)
1071  io.feedback_fast.bits.dataInvalidSqIdx := DontCare
1072
1073  val s2_vec_feedback = Wire(Valid(new VSFQFeedback))
1074  s2_vec_feedback.valid := s2_valid && !s2_ld_flow && !s2_hw_prf && s2_isvec
1075  s2_vec_feedback.bits.flowPtr := s2_out.sflowPtr
1076  s2_vec_feedback.bits.hit := !s2_tlb_miss
1077  s2_vec_feedback.bits.sourceType := RSFeedbackType.tlbMiss
1078  s2_vec_feedback.bits.paddr := s2_paddr
1079  s2_vec_feedback.bits.mmio := s2_st_mmio
1080  s2_vec_feedback.bits.atomic := s2_st_mmio
1081
1082  io.stu_io.lsq_replenish := s2_out
1083  io.stu_io.lsq_replenish.miss := io.ldu_io.dcache.resp.fire && io.ldu_io.dcache.resp.bits.miss
1084
1085  io.ldu_io.ldCancel.ld1Cancel.valid := s2_valid && s2_ld_flow && s2_out.isFirstIssue && (// issued from IQ
1086    s2_out.rep_info.need_rep || s2_ld_mmio                                                // exe fail or is mmio
1087  )
1088  io.ldu_io.ldCancel.ld1Cancel.bits := s2_out.deqPortIdx
1089
1090  // fast wakeup
1091  io.ldu_io.fast_uop.valid := RegNext(
1092    !io.ldu_io.dcache.s1_disable_fast_wakeup &&
1093    s1_valid &&
1094    !s1_kill &&
1095    !io.tlb.resp.bits.miss &&
1096    !io.ldu_io.lsq.forward.dataInvalidFast
1097  ) && (s2_valid && !s2_out.rep_info.need_rep && !s2_ld_mmio && s2_ld_flow) && !s2_isvec
1098  io.ldu_io.fast_uop.bits := RegNext(s1_out.uop)
1099
1100  //
1101  io.ldu_io.s2_ptr_chasing                    := RegEnable(s1_try_ptr_chasing && !s1_cancel_ptr_chasing, false.B, s1_fire)
1102
1103  // prefetch train
1104  io.prefetch_train.valid              := s2_valid && !s2_actually_mmio && !s2_in.tlbMiss
1105  io.prefetch_train.bits.fromLsPipelineBundle(s2_in)
1106  io.prefetch_train.bits.miss          := Mux(s2_ld_flow, io.ldu_io.dcache.resp.bits.miss, io.stu_io.dcache.resp.bits.miss) // TODO: use trace with bank conflict?
1107  io.prefetch_train.bits.meta_prefetch := Mux(s2_ld_flow, io.ldu_io.dcache.resp.bits.meta_prefetch, false.B)
1108  io.prefetch_train.bits.meta_access   := Mux(s2_ld_flow, io.ldu_io.dcache.resp.bits.meta_access, false.B)
1109
1110  io.prefetch_train_l1.valid              := s2_valid && !s2_actually_mmio && s2_ld_flow
1111  io.prefetch_train_l1.bits.fromLsPipelineBundle(s2_in)
1112  io.prefetch_train_l1.bits.miss          := io.ldu_io.dcache.resp.bits.miss
1113  io.prefetch_train_l1.bits.meta_prefetch := io.ldu_io.dcache.resp.bits.meta_prefetch
1114  io.prefetch_train_l1.bits.meta_access   := io.ldu_io.dcache.resp.bits.meta_access
1115  if (env.FPGAPlatform){
1116    io.ldu_io.dcache.s0_pc := DontCare
1117    io.ldu_io.dcache.s1_pc := DontCare
1118    io.ldu_io.dcache.s2_pc := DontCare
1119  }else{
1120    io.ldu_io.dcache.s0_pc := s0_out.uop.pc
1121    io.ldu_io.dcache.s1_pc := s1_out.uop.pc
1122    io.ldu_io.dcache.s2_pc := s2_out.uop.pc
1123  }
1124  io.ldu_io.dcache.s2_kill := s2_pmp.ld  || s2_actually_mmio || s2_kill
1125  io.stu_io.dcache.s2_kill := s2_pmp.st || s2_actually_mmio || s2_kill
1126  io.stu_io.dcache.s2_pc := s2_out.uop.pc
1127
1128  val s1_ld_left_fire = s1_valid && !s1_kill && s2_ready && s1_ld_flow
1129  val s2_ld_valid_dup = RegInit(0.U(6.W))
1130  s2_ld_valid_dup := 0x0.U(6.W)
1131  when (s1_ld_left_fire && !s1_out.isHWPrefetch && s1_ld_flow) { s2_ld_valid_dup := 0x3f.U(6.W) }
1132  when (s1_kill || s1_out.isHWPrefetch || !s1_ld_flow) { s2_ld_valid_dup := 0x0.U(6.W) }
1133  assert(RegNext((s2_valid === s2_ld_valid_dup(0)) || RegNext(s1_out.isHWPrefetch) || RegNext(!s1_ld_flow)))
1134
1135  // Pipeline
1136  // --------------------------------------------------------------------------------
1137  // stage 3
1138  // --------------------------------------------------------------------------------
1139  // writeback and update load queue
1140  val s3_valid        = RegNext(s2_valid && !s2_out.isHWPrefetch && !s2_out.uop.robIdx.needFlush(io.redirect))
1141  val s3_in           = RegEnable(s2_out, s2_fire)
1142  val s3_out          = Wire(Valid(new MemExuOutput))
1143  val s3_dcache_rep   = RegEnable(s2_dcache_fast_rep && s2_troublem, false.B, s2_fire)
1144  val s3_ld_valid_dup = RegEnable(s2_ld_valid_dup, s2_fire)
1145  val s3_fast_rep     = Wire(Bool())
1146  val s3_ld_flow      = RegNext(s2_ld_flow)
1147  val s3_troublem     = RegNext(s2_troublem)
1148  val s3_kill         = s3_in.uop.robIdx.needFlush(io.redirect)
1149  val s3_isvec        = RegNext(s2_isvec)
1150  s3_ready := !s3_valid || s3_kill || sx_can_go
1151
1152  // forwrad last beat
1153  val (s3_fwd_frm_d_chan, s3_fwd_data_frm_d_chan) = io.ldu_io.tl_d_channel.forward(s2_valid && s2_out.forward_tlDchannel, s2_out.mshrid, s2_out.paddr)
1154  val s3_fwd_data_valid = RegEnable(s2_fwd_data_valid, false.B, s2_valid)
1155  val s3_fwd_frm_d_chan_valid = (s3_fwd_frm_d_chan && s3_fwd_data_valid) && s3_ld_flow
1156
1157
1158  // s3 load fast replay
1159  io.ldu_io.fast_rep_out.valid := s3_valid &&
1160                                  s3_fast_rep &&
1161                                  !s3_in.uop.robIdx.needFlush(io.redirect) &&
1162                                  s3_ld_flow &&
1163                                  !s3_isvec
1164  io.ldu_io.fast_rep_out.bits := s3_in
1165
1166  io.ldu_io.lsq.ldin.valid := s3_valid &&
1167                              (!s3_fast_rep || !io.ldu_io.fast_rep_out.ready) &&
1168                              !s3_in.feedbacked &&
1169                              !s3_in.lateKill &&
1170                              s3_ld_flow
1171  io.ldu_io.lsq.ldin.bits := s3_in
1172  io.ldu_io.lsq.ldin.bits.miss := s3_in.miss && !s3_fwd_frm_d_chan_valid
1173
1174  /* <------- DANGEROUS: Don't change sequence here ! -------> */
1175  io.ldu_io.lsq.ldin.bits.data_wen_dup := s3_ld_valid_dup.asBools
1176  io.ldu_io.lsq.ldin.bits.replacementUpdated := io.ldu_io.dcache.resp.bits.replacementUpdated
1177  io.ldu_io.lsq.ldin.bits.missDbUpdated := RegNext(s2_fire && s2_in.hasROBEntry && !s2_in.tlbMiss && !s2_in.missDbUpdated)
1178
1179  val s3_dly_ld_err =
1180    if (EnableAccurateLoadError) {
1181      (s3_in.lateKill || io.ldu_io.dcache.resp.bits.error_delayed) && RegNext(io.csrCtrl.cache_error_enable)
1182    } else {
1183      WireInit(false.B)
1184    }
1185  io.ldu_io.s3_dly_ld_err := false.B // s3_dly_ld_err && s3_valid
1186  io.ldu_io.fast_rep_out.bits.delayedLoadError := s3_dly_ld_err
1187  io.ldu_io.lsq.ldin.bits.dcacheRequireReplay  := s3_dcache_rep
1188
1189  val s3_vp_match_fail = RegNext(io.ldu_io.lsq.forward.matchInvalid || io.ldu_io.sbuffer.matchInvalid) && s3_troublem
1190  val s3_ldld_rep_inst =
1191      io.ldu_io.lsq.ldld_nuke_query.resp.valid &&
1192      io.ldu_io.lsq.ldld_nuke_query.resp.bits.rep_frm_fetch &&
1193      RegNext(io.csrCtrl.ldld_vio_check_enable)
1194
1195  val s3_rep_info = WireInit(s3_in.rep_info)
1196  s3_rep_info.dcache_miss   := s3_in.rep_info.dcache_miss && !s3_fwd_frm_d_chan_valid && s3_troublem
1197  val s3_rep_frm_fetch = s3_vp_match_fail
1198  val s3_flushPipe = s3_ldld_rep_inst
1199  val s3_sel_rep_cause = PriorityEncoderOH(s3_rep_info.cause.asUInt)
1200  val s3_force_rep     = s3_sel_rep_cause(LoadReplayCauses.C_TM) &&
1201                         !s3_in.uop.exceptionVec(loadAddrMisaligned) &&
1202                         s3_troublem
1203
1204  val s3_ld_exception = ExceptionNO.selectByFu(s3_in.uop.exceptionVec, LduCfg).asUInt.orR && s3_ld_flow
1205  val s3_st_exception = ExceptionNO.selectByFu(s3_in.uop.exceptionVec, StaCfg).asUInt.orR && !s3_ld_flow
1206  val s3_exception    = s3_ld_exception || s3_st_exception
1207  when ((s3_ld_exception || s3_dly_ld_err || s3_rep_frm_fetch) && !s3_force_rep) {
1208    io.ldu_io.lsq.ldin.bits.rep_info.cause := 0.U.asTypeOf(s3_rep_info.cause.cloneType)
1209  } .otherwise {
1210    io.ldu_io.lsq.ldin.bits.rep_info.cause := VecInit(s3_sel_rep_cause.asBools)
1211  }
1212
1213  // Int flow, if hit, will be writebacked at s3
1214  s3_out.valid                := s3_valid &&
1215                                (!s3_ld_flow && !s3_in.feedbacked || !io.ldu_io.lsq.ldin.bits.rep_info.need_rep) && !s3_in.mmio
1216  s3_out.bits.uop             := s3_in.uop
1217  s3_out.bits.uop.exceptionVec(loadAccessFault) := (s3_dly_ld_err  || s3_in.uop.exceptionVec(loadAccessFault)) && s3_ld_flow
1218  s3_out.bits.uop.replayInst := s3_rep_frm_fetch
1219  s3_out.bits.data            := s3_in.data
1220  s3_out.bits.debug.isMMIO    := s3_in.mmio
1221  s3_out.bits.debug.isPerfCnt := false.B
1222  s3_out.bits.debug.paddr     := s3_in.paddr
1223  s3_out.bits.debug.vaddr     := s3_in.vaddr
1224
1225  when (s3_force_rep) {
1226    s3_out.bits.uop.exceptionVec := 0.U.asTypeOf(s3_in.uop.exceptionVec.cloneType)
1227  }
1228
1229  io.ldu_io.rollback.valid := s3_valid && (s3_rep_frm_fetch || s3_flushPipe) && !s3_exception && s3_ld_flow
1230  io.ldu_io.rollback.bits             := DontCare
1231  io.ldu_io.rollback.bits.isRVC       := s3_out.bits.uop.preDecodeInfo.isRVC
1232  io.ldu_io.rollback.bits.robIdx      := s3_out.bits.uop.robIdx
1233  io.ldu_io.rollback.bits.ftqIdx      := s3_out.bits.uop.ftqPtr
1234  io.ldu_io.rollback.bits.ftqOffset   := s3_out.bits.uop.ftqOffset
1235  io.ldu_io.rollback.bits.level       := Mux(s3_rep_frm_fetch, RedirectLevel.flush, RedirectLevel.flushAfter)
1236  io.ldu_io.rollback.bits.cfiUpdate.target := s3_out.bits.uop.pc
1237  io.ldu_io.rollback.bits.debug_runahead_checkpoint_id := s3_out.bits.uop.debugInfo.runahead_checkpoint_id
1238  /* <------- DANGEROUS: Don't change sequence here ! -------> */
1239  io.ldu_io.lsq.ldin.bits.uop := s3_out.bits.uop
1240
1241  val s3_revoke = s3_exception || io.ldu_io.lsq.ldin.bits.rep_info.need_rep
1242  io.ldu_io.lsq.ldld_nuke_query.revoke := s3_revoke
1243  io.ldu_io.lsq.stld_nuke_query.revoke := s3_revoke
1244
1245  // feedback slow
1246  s3_fast_rep := RegNext(s2_fast_rep) &&
1247                 !s3_in.feedbacked &&
1248                 !s3_in.lateKill &&
1249                 !s3_rep_frm_fetch &&
1250                 !s3_exception
1251
1252  val s3_fb_no_waiting = !s3_in.isLoadReplay && !(s3_fast_rep && io.ldu_io.fast_rep_out.ready) && !s3_in.feedbacked
1253
1254  //
1255  io.feedback_slow.valid                 := s3_valid && !s3_in.uop.robIdx.needFlush(io.redirect) && s3_fb_no_waiting && s3_ld_flow
1256  io.feedback_slow.bits.hit              := !io.ldu_io.lsq.ldin.bits.rep_info.need_rep || io.ldu_io.lsq.ldin.ready
1257  io.feedback_slow.bits.flushState       := s3_in.ptwBack
1258  io.feedback_slow.bits.robIdx           := s3_in.uop.robIdx
1259  io.feedback_slow.bits.sourceType       := RSFeedbackType.lrqFull
1260  io.feedback_slow.bits.dataInvalidSqIdx := DontCare
1261
1262  io.vec_stu_io.feedbackSlow.valid := RegNext(s2_vec_feedback.valid && !s2_out.uop.robIdx.needFlush(io.redirect))
1263  io.vec_stu_io.feedbackSlow.bits := RegNext(s2_vec_feedback.bits)
1264
1265  io.ldu_io.ldCancel.ld2Cancel.valid := s3_valid && s3_ld_flow && s3_in.isFirstIssue && ( // issued from IQ and is load
1266    io.ldu_io.lsq.ldin.bits.rep_info.need_rep || s3_in.mmio                            // exe fail or is mmio
1267  )
1268  io.ldu_io.ldCancel.ld2Cancel.bits := s3_in.deqPortIdx
1269
1270  // data from dcache hit
1271  val s3_ld_raw_data_frm_cache = Wire(new LoadDataFromDcacheBundle)
1272  s3_ld_raw_data_frm_cache.respDcacheData       := io.ldu_io.dcache.resp.bits.data_delayed
1273  s3_ld_raw_data_frm_cache.forwardMask          := RegEnable(s2_fwd_mask, s2_valid)
1274  s3_ld_raw_data_frm_cache.forwardData          := RegEnable(s2_fwd_data, s2_valid)
1275  s3_ld_raw_data_frm_cache.uop                  := RegEnable(s2_out.uop, s2_valid)
1276  s3_ld_raw_data_frm_cache.addrOffset           := RegEnable(s2_out.paddr(3, 0), s2_valid)
1277  s3_ld_raw_data_frm_cache.forward_D            := RegEnable(s2_fwd_frm_d_chan, false.B, s2_valid) || s3_fwd_frm_d_chan_valid
1278  s3_ld_raw_data_frm_cache.forwardData_D        := Mux(s3_fwd_frm_d_chan_valid, s3_fwd_data_frm_d_chan, RegEnable(s2_fwd_data_frm_d_chan, s2_valid))
1279  s3_ld_raw_data_frm_cache.forward_mshr         := RegEnable(s2_fwd_frm_mshr, false.B, s2_valid)
1280  s3_ld_raw_data_frm_cache.forwardData_mshr     := RegEnable(s2_fwd_data_frm_mshr, s2_valid)
1281  s3_ld_raw_data_frm_cache.forward_result_valid := RegEnable(s2_fwd_data_valid, false.B, s2_valid)
1282
1283  val s3_merged_data_frm_cache = s3_ld_raw_data_frm_cache.mergedData()
1284  val s3_picked_data_frm_cache = LookupTree(s3_ld_raw_data_frm_cache.addrOffset, List(
1285    "b0000".U -> s3_merged_data_frm_cache(63,    0),
1286    "b0001".U -> s3_merged_data_frm_cache(63,    8),
1287    "b0010".U -> s3_merged_data_frm_cache(63,   16),
1288    "b0011".U -> s3_merged_data_frm_cache(63,   24),
1289    "b0100".U -> s3_merged_data_frm_cache(63,   32),
1290    "b0101".U -> s3_merged_data_frm_cache(63,   40),
1291    "b0110".U -> s3_merged_data_frm_cache(63,   48),
1292    "b0111".U -> s3_merged_data_frm_cache(63,   56),
1293    "b1000".U -> s3_merged_data_frm_cache(127,  64),
1294    "b1001".U -> s3_merged_data_frm_cache(127,  72),
1295    "b1010".U -> s3_merged_data_frm_cache(127,  80),
1296    "b1011".U -> s3_merged_data_frm_cache(127,  88),
1297    "b1100".U -> s3_merged_data_frm_cache(127,  96),
1298    "b1101".U -> s3_merged_data_frm_cache(127, 104),
1299    "b1110".U -> s3_merged_data_frm_cache(127, 112),
1300    "b1111".U -> s3_merged_data_frm_cache(127, 120)
1301  ))
1302  val s3_ld_data_frm_cache = rdataHelper(s3_ld_raw_data_frm_cache.uop, s3_picked_data_frm_cache)
1303
1304  // FIXME: add 1 cycle delay ?
1305  io.ldout.bits      := s3_out.bits
1306  io.ldout.bits.data := s3_ld_data_frm_cache
1307  io.ldout.valid     := s3_out.valid && !s3_out.bits.uop.robIdx.needFlush(io.redirect) && s3_ld_flow && !s3_isvec
1308
1309  // for uncache
1310  io.ldu_io.lsq.uncache.ready := true.B
1311
1312  // fast load to load forward
1313  if (EnableLoadToLoadForward) {
1314    io.ldu_io.l2l_fwd_out.valid      := s3_out.valid && !s3_in.lateKill && s3_ld_flow
1315    io.ldu_io.l2l_fwd_out.data       := s3_ld_data_frm_cache
1316    io.ldu_io.l2l_fwd_out.dly_ld_err := s3_dly_ld_err // ecc delayed error
1317  } else {
1318    io.ldu_io.l2l_fwd_out.valid      := false.B
1319    io.ldu_io.l2l_fwd_out.data       := DontCare
1320    io.ldu_io.l2l_fwd_out.dly_ld_err := DontCare
1321  }
1322
1323  // hybrid unit writeback to rob
1324  // delay params
1325  val SelectGroupSize   = RollbackGroupSize
1326  val lgSelectGroupSize = log2Ceil(SelectGroupSize)
1327  val TotalSelectCycles = scala.math.ceil(log2Ceil(LoadQueueRAWSize).toFloat / lgSelectGroupSize).toInt + 1
1328  val TotalDelayCycles  = TotalSelectCycles - 2
1329
1330  // writeback
1331  val sx_valid = Wire(Vec(TotalDelayCycles + 1, Bool()))
1332  val sx_ready = Wire(Vec(TotalDelayCycles + 1, Bool()))
1333  val sx_in    = Wire(Vec(TotalDelayCycles + 1, new MemExuOutput))
1334
1335  sx_can_go := sx_ready.head
1336  for (i <- 0 until TotalDelayCycles + 1) {
1337    if (i == 0) {
1338      sx_valid(i) := s3_valid &&
1339                    !s3_ld_flow &&
1340                    !s3_in.feedbacked &&
1341                    !s3_in.mmio
1342      sx_in(i)    := s3_out.bits
1343      sx_ready(i) := !s3_valid(i) || sx_in(i).uop.robIdx.needFlush(io.redirect) || (if (TotalDelayCycles == 0) io.stout.ready else sx_ready(i+1))
1344    } else {
1345      val cur_kill   = sx_in(i).uop.robIdx.needFlush(io.redirect)
1346      val cur_can_go = (if (i == TotalDelayCycles) io.stout.ready else sx_ready(i+1))
1347      val cur_fire   = sx_valid(i) && !cur_kill && cur_can_go
1348      val prev_fire  = sx_valid(i-1) && !sx_in(i-1).uop.robIdx.needFlush(io.redirect) && sx_ready(i)
1349
1350      sx_ready(i) := !sx_valid(i) || cur_kill || (if (i == TotalDelayCycles) io.stout.ready else sx_ready(i+1))
1351      val sx_valid_can_go = prev_fire || cur_fire || cur_kill
1352      sx_valid(i) := RegEnable(Mux(prev_fire, true.B, false.B), sx_valid_can_go)
1353      sx_in(i) := RegEnable(sx_in(i-1), prev_fire)
1354    }
1355  }
1356
1357  val sx_last_valid = sx_valid.takeRight(1).head
1358  val sx_last_ready = sx_ready.takeRight(1).head
1359  val sx_last_in    = sx_in.takeRight(1).head
1360
1361  sx_last_ready  := !sx_last_valid || sx_last_in.uop.robIdx.needFlush(io.redirect) || io.stout.ready
1362  io.stout.valid := sx_last_valid && !sx_last_in.uop.robIdx.needFlush(io.redirect) && FuType.isStore(sx_last_in.uop.fuType)
1363  io.stout.bits  := sx_last_in
1364
1365   // trigger
1366  val ld_trigger = FuType.isLoad(io.ldout.bits.uop.fuType)
1367  val last_valid_data = RegEnable(io.ldout.bits.data, io.stout.fire)
1368  val hit_ld_addr_trig_hit_vec = Wire(Vec(TriggerNum, Bool()))
1369  val lq_ld_addr_trig_hit_vec = RegNext(io.ldu_io.lsq.trigger.lqLoadAddrTriggerHitVec)
1370  (0 until TriggerNum).map{i => {
1371    val tdata2    = RegNext(RegNext(io.ldu_io.trigger(i).tdata2))
1372    val matchType = RegNext(RegNext(io.ldu_io.trigger(i).matchType))
1373    val tEnable   = RegNext(RegNext(io.ldu_io.trigger(i).tEnable))
1374
1375    hit_ld_addr_trig_hit_vec(i)        := TriggerCmp(RegNext(s3_in.vaddr), tdata2, matchType, tEnable)
1376    io.ldu_io.trigger(i).addrHit       := Mux(io.ldout.valid && ld_trigger, hit_ld_addr_trig_hit_vec(i), lq_ld_addr_trig_hit_vec(i))
1377    io.ldu_io.trigger(i).lastDataHit   := TriggerCmp(last_valid_data, tdata2, matchType, tEnable)
1378  }}
1379  io.ldu_io.lsq.trigger.hitLoadAddrTriggerHitVec := hit_ld_addr_trig_hit_vec
1380
1381  // FIXME: please move this part to LoadQueueReplay
1382  io.ldu_io.debug_ls := DontCare
1383  io.stu_io.debug_ls := DontCare
1384  io.stu_io.debug_ls.s1.isTlbFirstMiss := io.tlb.resp.valid && io.tlb.resp.bits.miss && io.tlb.resp.bits.debug.isFirstIssue && !s1_in.isHWPrefetch && !s1_ld_flow
1385  io.stu_io.debug_ls.s1_robIdx := s1_in.uop.robIdx.value
1386
1387 // Topdown
1388  io.ldu_io.lsTopdownInfo.s1.robIdx          := s1_in.uop.robIdx.value
1389  io.ldu_io.lsTopdownInfo.s1.vaddr_valid     := s1_valid && s1_in.hasROBEntry
1390  io.ldu_io.lsTopdownInfo.s1.vaddr_bits      := s1_vaddr
1391  io.ldu_io.lsTopdownInfo.s2.robIdx          := s2_in.uop.robIdx.value
1392  io.ldu_io.lsTopdownInfo.s2.paddr_valid     := s2_fire && s2_in.hasROBEntry && !s2_in.tlbMiss
1393  io.ldu_io.lsTopdownInfo.s2.paddr_bits      := s2_in.paddr
1394  io.ldu_io.lsTopdownInfo.s2.first_real_miss := io.ldu_io.dcache.resp.bits.real_miss
1395  io.ldu_io.lsTopdownInfo.s2.cache_miss_en   := s2_fire && s2_in.hasROBEntry && !s2_in.tlbMiss && !s2_in.missDbUpdated
1396
1397  // perf cnt
1398  XSPerfAccumulate("s0_in_valid",                  io.lsin.valid)
1399  XSPerfAccumulate("s0_in_block",                  io.lsin.valid && !io.lsin.fire)
1400  XSPerfAccumulate("s0_in_fire_first_issue",       s0_valid && s0_isFirstIssue)
1401  XSPerfAccumulate("s0_lsq_fire_first_issue",      io.ldu_io.replay.fire)
1402  XSPerfAccumulate("s0_ldu_fire_first_issue",      io.lsin.fire && s0_isFirstIssue)
1403  XSPerfAccumulate("s0_fast_replay_issue",         io.ldu_io.fast_rep_in.fire)
1404  XSPerfAccumulate("s0_stall_out",                 s0_valid && !s0_can_go)
1405  XSPerfAccumulate("s0_stall_ld_dcache",           s0_valid && !io.ldu_io.dcache.req.ready)
1406  XSPerfAccumulate("s0_stall_st_dcache",           s0_valid && !io.stu_io.dcache.req.ready)
1407  XSPerfAccumulate("s0_addr_spec_success",         s0_fire && s0_vaddr(VAddrBits-1, 12) === io.lsin.bits.src(0)(VAddrBits-1, 12))
1408  XSPerfAccumulate("s0_addr_spec_failed",          s0_fire && s0_vaddr(VAddrBits-1, 12) =/= io.lsin.bits.src(0)(VAddrBits-1, 12))
1409  XSPerfAccumulate("s0_addr_spec_success_once",    s0_fire && s0_vaddr(VAddrBits-1, 12) === io.lsin.bits.src(0)(VAddrBits-1, 12) && s0_isFirstIssue)
1410  XSPerfAccumulate("s0_addr_spec_failed_once",     s0_fire && s0_vaddr(VAddrBits-1, 12) =/= io.lsin.bits.src(0)(VAddrBits-1, 12) && s0_isFirstIssue)
1411  XSPerfAccumulate("s0_forward_tl_d_channel",      s0_out.forward_tlDchannel)
1412  XSPerfAccumulate("s0_hardware_prefetch_fire",    s0_fire && s0_hw_prf_select)
1413  XSPerfAccumulate("s0_software_prefetch_fire",    s0_fire && s0_prf && s0_int_iss_select)
1414  XSPerfAccumulate("s0_hardware_prefetch_blocked", io.ldu_io.prefetch_req.valid && !s0_hw_prf_select)
1415  XSPerfAccumulate("s0_hardware_prefetch_total",   io.ldu_io.prefetch_req.valid)
1416
1417  XSPerfAccumulate("s1_in_valid",                  s1_valid)
1418  XSPerfAccumulate("s1_in_fire",                   s1_fire)
1419  XSPerfAccumulate("s1_in_fire_first_issue",       s1_fire && s1_in.isFirstIssue)
1420  XSPerfAccumulate("s1_tlb_miss",                  s1_fire && s1_tlb_miss)
1421  XSPerfAccumulate("s1_tlb_miss_first_issue",      s1_fire && s1_tlb_miss && s1_in.isFirstIssue)
1422  XSPerfAccumulate("s1_stall_out",                 s1_valid && !s1_can_go)
1423  XSPerfAccumulate("s1_late_kill",                 s1_valid && s1_fast_rep_kill)
1424
1425  XSPerfAccumulate("s2_in_valid",                  s2_valid)
1426  XSPerfAccumulate("s2_in_fire",                   s2_fire)
1427  XSPerfAccumulate("s2_in_fire_first_issue",       s2_fire && s2_in.isFirstIssue)
1428  XSPerfAccumulate("s2_dcache_miss",               s2_fire && io.ldu_io.dcache.resp.bits.miss)
1429  XSPerfAccumulate("s2_dcache_miss_first_issue",   s2_fire && io.ldu_io.dcache.resp.bits.miss && s2_in.isFirstIssue)
1430  XSPerfAccumulate("s2_dcache_real_miss_first_issue",   s2_fire && io.ldu_io.dcache.resp.bits.miss && s2_in.isFirstIssue)
1431  XSPerfAccumulate("s2_full_forward",              s2_fire && s2_full_fwd)
1432  XSPerfAccumulate("s2_dcache_miss_full_forward",  s2_fire && s2_dcache_miss)
1433  XSPerfAccumulate("s2_fwd_frm_d_can",             s2_valid && s2_fwd_frm_d_chan)
1434  XSPerfAccumulate("s2_fwd_frm_d_chan_or_mshr",    s2_valid && s2_fwd_frm_d_chan_or_mshr)
1435  XSPerfAccumulate("s2_stall_out",                 s2_fire && !s2_can_go)
1436  XSPerfAccumulate("s2_prefetch",                  s2_fire && s2_prf)
1437  XSPerfAccumulate("s2_prefetch_ignored",          s2_fire && s2_prf && s2_mq_nack) // ignore prefetch for mshr full / miss req port conflict
1438  XSPerfAccumulate("s2_prefetch_miss",             s2_fire && s2_prf && io.ldu_io.dcache.resp.bits.miss) // prefetch req miss in l1
1439  XSPerfAccumulate("s2_prefetch_hit",              s2_fire && s2_prf && !io.ldu_io.dcache.resp.bits.miss) // prefetch req hit in l1
1440  XSPerfAccumulate("s2_prefetch_accept",           s2_fire && s2_prf && io.ldu_io.dcache.resp.bits.miss && !s2_mq_nack) // prefetch a missed line in l1, and l1 accepted it
1441  XSPerfAccumulate("s2_forward_req",               s2_fire && s2_in.forward_tlDchannel)
1442  XSPerfAccumulate("s2_successfully_forward_channel_D", s2_fire && s2_fwd_frm_d_chan && s2_fwd_data_valid)
1443  XSPerfAccumulate("s2_successfully_forward_mshr",      s2_fire && s2_fwd_frm_mshr && s2_fwd_data_valid)
1444
1445  XSPerfAccumulate("s3_fwd_frm_d_chan",            s3_valid && s3_fwd_frm_d_chan_valid)
1446
1447  XSPerfAccumulate("load_to_load_forward",                      s1_try_ptr_chasing && !s1_ptr_chasing_canceled)
1448  XSPerfAccumulate("load_to_load_forward_try",                  s1_try_ptr_chasing)
1449  XSPerfAccumulate("load_to_load_forward_fail",                 s1_cancel_ptr_chasing)
1450  XSPerfAccumulate("load_to_load_forward_fail_cancelled",       s1_cancel_ptr_chasing && s1_ptr_chasing_canceled)
1451  XSPerfAccumulate("load_to_load_forward_fail_wakeup_mismatch", s1_cancel_ptr_chasing && !s1_ptr_chasing_canceled && s1_not_fast_match)
1452  XSPerfAccumulate("load_to_load_forward_fail_op_not_ld",       s1_cancel_ptr_chasing && !s1_ptr_chasing_canceled && !s1_not_fast_match && s1_fu_op_type_not_ld)
1453  XSPerfAccumulate("load_to_load_forward_fail_addr_align",      s1_cancel_ptr_chasing && !s1_ptr_chasing_canceled && !s1_not_fast_match && !s1_fu_op_type_not_ld && s1_addr_misaligned)
1454  XSPerfAccumulate("load_to_load_forward_fail_set_mismatch",    s1_cancel_ptr_chasing && !s1_ptr_chasing_canceled && !s1_not_fast_match && !s1_fu_op_type_not_ld && !s1_addr_misaligned && s1_addr_mismatch)
1455
1456  // bug lyq: some signals in perfEvents are no longer suitable for the current MemBlock design
1457  // hardware performance counter
1458  val perfEvents = Seq(
1459    ("load_s0_in_fire         ", s0_fire                                                        ),
1460    ("load_to_load_forward    ", s1_fire && s1_try_ptr_chasing && !s1_ptr_chasing_canceled      ),
1461    ("stall_dcache            ", s0_valid && s0_can_go && !io.ldu_io.dcache.req.ready           ),
1462    ("load_s1_in_fire         ", s0_fire                                                        ),
1463    ("load_s1_tlb_miss        ", s1_fire && io.tlb.resp.bits.miss                               ),
1464    ("load_s2_in_fire         ", s1_fire                                                        ),
1465    ("load_s2_dcache_miss     ", s2_fire && io.ldu_io.dcache.resp.bits.miss                     ),
1466  )
1467  generatePerfEvent()
1468}