xref: /XiangShan/src/main/scala/xiangshan/mem/pipeline/HybridUnit.scala (revision bb2f3f51dd67f6e16e0cc1ffe43368c9fc7e4aef)
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, TlbHintReq, 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 tlb_hint      = Flipped(new TlbHintReq)
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      // iq wakeup, use to wakeup consumer uop at load s2
92      val wakeup = ValidIO(new DynInst)
93
94      // load ecc error
95      val s3_dly_ld_err = Output(Bool()) // Note that io.s3_dly_ld_err and io.lsq.s3_dly_ld_err is different
96
97      // schedule error query
98      val stld_nuke_query = Flipped(Vec(StorePipelineWidth, Valid(new StoreNukeQueryIO)))
99
100      // queue-based replay
101      val replay       = Flipped(Decoupled(new LsPipelineBundle))
102      val lq_rep_full  = Input(Bool())
103
104      // misc
105      val s2_ptr_chasing = Output(Bool()) // provide right pc for hw prefetch
106
107      // Load fast replay path
108      val fast_rep_in  = Flipped(Decoupled(new LqWriteBundle))
109      val fast_rep_out = Decoupled(new LqWriteBundle)
110
111      // Load RAR rollback
112      val rollback = Valid(new Redirect)
113
114      // perf
115      val debug_ls         = Output(new DebugLsInfoBundle)
116      val lsTopdownInfo    = Output(new LsTopdownInfo)
117    }
118
119    val stu_io = new Bundle() {
120      val dcache          = new DCacheStoreIO
121      val prefetch_req    = Flipped(DecoupledIO(new StorePrefetchReq))
122      val issue           = Valid(new MemExuInput)
123      val lsq             = ValidIO(new LsPipelineBundle)
124      val lsq_replenish   = Output(new LsPipelineBundle())
125      val stld_nuke_query = Valid(new StoreNukeQueryIO)
126      val st_mask_out     = Valid(new StoreMaskBundle)
127      val debug_ls        = Output(new DebugLsInfoBundle)
128    }
129
130    val vec_stu_io = new Bundle() {
131      val in = Flipped(DecoupledIO(new VecPipeBundle()))
132      val isFirstIssue = Input(Bool())
133      val lsq = ValidIO(new LsPipelineBundle())
134      val feedbackSlow = ValidIO(new VSFQFeedback)
135    }
136
137    // speculative for gated control
138    val s0_prefetch_spec = Output(Bool())
139    val s1_prefetch_spec = Output(Bool())
140    // prefetch
141    val prefetch_train            = ValidIO(new LdPrefetchTrainBundle()) // provide prefetch info to sms
142    val prefetch_train_l1         = ValidIO(new LdPrefetchTrainBundle()) // provide prefetch info to stream & stride
143    val canAcceptLowConfPrefetch  = Output(Bool())
144    val canAcceptHighConfPrefetch = Output(Bool())
145    val correctMissTrain          = Input(Bool())
146
147    // data path
148    val tlb           = new TlbRequestIO(2)
149    val pmp           = Flipped(new PMPRespBundle()) // arrive same to tlb now
150
151    // rs feedback
152    val feedback_fast = ValidIO(new RSFeedback) // stage 2
153    val feedback_slow = ValidIO(new RSFeedback) // stage 3
154  })
155
156  val StorePrefetchL1Enabled = EnableStorePrefetchAtCommit || EnableStorePrefetchAtIssue || EnableStorePrefetchSPB
157  val s1_ready, s2_ready, s3_ready, sx_can_go = WireInit(false.B)
158
159  // Pipeline
160  // --------------------------------------------------------------------------------
161  // stage 0
162  // --------------------------------------------------------------------------------
163  // generate addr, use addr to query DCache and DTLB
164  val s0_valid         = Wire(Bool())
165  val s0_dcache_ready  = Wire(Bool())
166  val s0_kill          = Wire(Bool())
167  val s0_vaddr         = Wire(UInt(VAddrBits.W))
168  val s0_mask          = Wire(UInt((VLEN/8).W))
169  val s0_uop           = Wire(new DynInst)
170  val s0_has_rob_entry = Wire(Bool())
171  val s0_mshrid        = Wire(UInt())
172  val s0_try_l2l       = Wire(Bool())
173  val s0_rep_carry     = Wire(new ReplayCarry(nWays))
174  val s0_isFirstIssue  = Wire(Bool())
175  val s0_fast_rep      = Wire(Bool())
176  val s0_ld_rep        = Wire(Bool())
177  val s0_l2l_fwd       = Wire(Bool())
178  val s0_sched_idx     = Wire(UInt())
179  val s0_can_go        = s1_ready
180  val s0_fire          = s0_valid && s0_dcache_ready && s0_can_go
181  val s0_out           = Wire(new LqWriteBundle)
182  // vector
183  val s0_isvec = WireInit(false.B)
184  val s0_vecActive = WireInit(true.B)
185  // val s0_flowPtr = WireInit(0.U.asTypeOf(new VsFlowPtr))
186  val s0_isLastElem = WireInit(false.B)
187
188  // load flow select/gen
189  // src0: super load replayed by LSQ (cache miss replay) (io.ldu_io.replay)
190  // src1: fast load replay (io.ldu_io.fast_rep_in)
191  // src2: load replayed by LSQ (io.ldu_io.replay)
192  // src3: hardware prefetch from prefetchor (high confidence) (io.prefetch)
193  // src4: int read / software prefetch first issue from RS (io.in)
194  // src5: vec read first issue from RS (TODO)
195  // src6: load try pointchaising when no issued or replayed load (io.fastpath)
196  // src7: hardware prefetch from prefetchor (high confidence) (io.prefetch)
197  // priority: high to low
198  val s0_ld_flow             = FuType.isLoad(s0_uop.fuType) || FuType.isVLoad(s0_uop.fuType)
199  val s0_rep_stall           = io.lsin.valid && isAfter(io.ldu_io.replay.bits.uop.robIdx, io.lsin.bits.uop.robIdx)
200  val s0_super_ld_rep_valid  = io.ldu_io.replay.valid && io.ldu_io.replay.bits.forward_tlDchannel
201  val s0_ld_fast_rep_valid   = io.ldu_io.fast_rep_in.valid
202  val s0_ld_rep_valid        = io.ldu_io.replay.valid && !io.ldu_io.replay.bits.forward_tlDchannel && !s0_rep_stall
203  val s0_high_conf_prf_valid = io.ldu_io.prefetch_req.valid && io.ldu_io.prefetch_req.bits.confidence > 0.U
204  val s0_int_iss_valid       = io.lsin.valid // int flow first issue or software prefetch
205  val s0_vec_iss_valid       = io.vec_stu_io.in.valid
206  val s0_l2l_fwd_valid       = io.ldu_io.l2l_fwd_in.valid && io.ldu_io.ld_fast_match
207  val s0_low_conf_prf_valid  = io.ldu_io.prefetch_req.valid && io.ldu_io.prefetch_req.bits.confidence === 0.U
208  dontTouch(s0_super_ld_rep_valid)
209  dontTouch(s0_ld_fast_rep_valid)
210  dontTouch(s0_ld_rep_valid)
211  dontTouch(s0_high_conf_prf_valid)
212  dontTouch(s0_int_iss_valid)
213  dontTouch(s0_vec_iss_valid)
214  dontTouch(s0_l2l_fwd_valid)
215  dontTouch(s0_low_conf_prf_valid)
216
217  // load flow source ready
218  val s0_super_ld_rep_ready  = WireInit(true.B)
219  val s0_ld_fast_rep_ready   = !s0_super_ld_rep_valid
220  val s0_ld_rep_ready        = !s0_super_ld_rep_valid &&
221                               !s0_ld_fast_rep_valid
222  val s0_high_conf_prf_ready = !s0_super_ld_rep_valid &&
223                               !s0_ld_fast_rep_valid &&
224                               !s0_ld_rep_valid
225
226  val s0_int_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
231  val s0_vec_iss_ready       = !s0_super_ld_rep_valid &&
232                               !s0_ld_fast_rep_valid &&
233                               !s0_ld_rep_valid &&
234                               !s0_high_conf_prf_valid &&
235                               !s0_int_iss_valid
236
237  val s0_l2l_fwd_ready       = !s0_super_ld_rep_valid &&
238                               !s0_ld_fast_rep_valid &&
239                               !s0_ld_rep_valid &&
240                               !s0_high_conf_prf_valid &&
241                               !s0_int_iss_valid &&
242                               !s0_vec_iss_valid
243
244  val s0_low_conf_prf_ready  = !s0_super_ld_rep_valid &&
245                               !s0_ld_fast_rep_valid &&
246                               !s0_ld_rep_valid &&
247                               !s0_high_conf_prf_valid &&
248                               !s0_int_iss_valid &&
249                               !s0_vec_iss_valid &&
250                               !s0_l2l_fwd_valid
251  dontTouch(s0_super_ld_rep_ready)
252  dontTouch(s0_ld_fast_rep_ready)
253  dontTouch(s0_ld_rep_ready)
254  dontTouch(s0_high_conf_prf_ready)
255  dontTouch(s0_int_iss_ready)
256  dontTouch(s0_vec_iss_ready)
257  dontTouch(s0_l2l_fwd_ready)
258  dontTouch(s0_low_conf_prf_ready)
259
260  // load flow source select (OH)
261  val s0_super_ld_rep_select = s0_super_ld_rep_valid && s0_super_ld_rep_ready
262  val s0_ld_fast_rep_select  = s0_ld_fast_rep_valid && s0_ld_fast_rep_ready
263  val s0_ld_rep_select       = s0_ld_rep_valid && s0_ld_rep_ready
264  val s0_hw_prf_select       = s0_high_conf_prf_ready && s0_high_conf_prf_valid ||
265                               s0_low_conf_prf_ready && s0_low_conf_prf_valid
266  val s0_int_iss_select      = s0_int_iss_ready && s0_int_iss_valid
267  val s0_vec_iss_select      = s0_vec_iss_ready && s0_vec_iss_valid
268  val s0_l2l_fwd_select      = s0_l2l_fwd_ready && s0_l2l_fwd_valid
269  dontTouch(s0_super_ld_rep_select)
270  dontTouch(s0_ld_fast_rep_select)
271  dontTouch(s0_ld_rep_select)
272  dontTouch(s0_hw_prf_select)
273  dontTouch(s0_int_iss_select)
274  dontTouch(s0_vec_iss_select)
275  dontTouch(s0_l2l_fwd_select)
276
277  s0_valid := (s0_super_ld_rep_valid ||
278               s0_ld_fast_rep_valid ||
279               s0_ld_rep_valid ||
280               s0_high_conf_prf_valid ||
281               s0_int_iss_valid ||
282               s0_vec_iss_valid ||
283               s0_l2l_fwd_valid ||
284               s0_low_conf_prf_valid) && !s0_kill
285
286  // which is S0's out is ready and dcache is ready
287  val s0_try_ptr_chasing      = s0_l2l_fwd_select
288  val s0_do_try_ptr_chasing   = s0_try_ptr_chasing && s0_can_go && io.ldu_io.dcache.req.ready
289  val s0_ptr_chasing_vaddr    = io.ldu_io.l2l_fwd_in.data(5, 0) +& io.ldu_io.ld_fast_imm(5, 0)
290  val s0_ptr_chasing_canceled = WireInit(false.B)
291  s0_kill := s0_ptr_chasing_canceled || (s0_out.uop.robIdx.needFlush(io.redirect) && !s0_try_ptr_chasing)
292
293  // prefetch related ctrl signal
294  val s0_prf    = Wire(Bool())
295  val s0_prf_rd = Wire(Bool())
296  val s0_prf_wr = Wire(Bool())
297  val s0_hw_prf = s0_hw_prf_select
298
299  io.canAcceptLowConfPrefetch  := s0_low_conf_prf_ready && io.ldu_io.dcache.req.ready
300  io.canAcceptHighConfPrefetch := s0_high_conf_prf_ready && io.ldu_io.dcache.req.ready
301
302  if (StorePrefetchL1Enabled) {
303    s0_dcache_ready := Mux(s0_ld_flow, io.ldu_io.dcache.req.ready, io.stu_io.dcache.req.ready)
304  } else {
305    s0_dcache_ready := Mux(s0_ld_flow, io.ldu_io.dcache.req.ready, true.B)
306  }
307
308  // query DTLB
309  io.tlb.req.valid                   := s0_valid && s0_dcache_ready
310  io.tlb.req.bits.cmd                := Mux(s0_prf,
311                                         Mux(s0_prf_wr, TlbCmd.write, TlbCmd.read),
312                                         Mux(s0_ld_flow, TlbCmd.read, TlbCmd.write)
313                                       )
314  io.tlb.req.bits.vaddr              := Mux(s0_hw_prf_select, io.ldu_io.prefetch_req.bits.paddr, s0_vaddr)
315  io.tlb.req.bits.size               := Mux(s0_isvec, io.vec_stu_io.in.bits.alignedType(1, 0), LSUOpType.size(s0_uop.fuOpType)) // may broken if use it in feature
316  io.tlb.req.bits.kill               := s0_kill
317  io.tlb.req.bits.memidx.is_ld       := s0_ld_flow
318  io.tlb.req.bits.memidx.is_st       := !s0_ld_flow
319  io.tlb.req.bits.memidx.idx         := s0_uop.lqIdx.value
320  io.tlb.req.bits.debug.robIdx       := s0_uop.robIdx
321  io.tlb.req.bits.no_translate       := s0_hw_prf_select  // hw b.reqetch addr does not need to be translated
322  io.tlb.req.bits.debug.pc           := s0_uop.pc
323  io.tlb.req.bits.debug.isFirstIssue := s0_isFirstIssue
324
325  // query DCache
326  // for load
327  io.ldu_io.dcache.req.valid             := s0_valid && s0_dcache_ready && s0_ld_flow
328  io.ldu_io.dcache.req.bits.cmd          :=  Mux(s0_prf_rd, MemoryOpConstants.M_PFR,
329                                              Mux(s0_prf_wr, MemoryOpConstants.M_PFW, MemoryOpConstants.M_XRD))
330  io.ldu_io.dcache.req.bits.vaddr        := s0_vaddr
331  io.ldu_io.dcache.req.bits.mask         := s0_mask
332  io.ldu_io.dcache.req.bits.data         := DontCare
333  io.ldu_io.dcache.req.bits.isFirstIssue := s0_isFirstIssue
334  io.ldu_io.dcache.req.bits.instrtype    := Mux(s0_prf, DCACHE_PREFETCH_SOURCE.U, LOAD_SOURCE.U)
335  io.ldu_io.dcache.req.bits.debug_robIdx := s0_uop.robIdx.value
336  io.ldu_io.dcache.req.bits.replayCarry  := s0_rep_carry
337  io.ldu_io.dcache.req.bits.id           := DontCare // TODO: update cache meta
338  io.ldu_io.dcache.pf_source             := Mux(s0_hw_prf_select, io.ldu_io.prefetch_req.bits.pf_source.value, L1_HW_PREFETCH_NULL)
339  io.ldu_io.dcache.is128Req              := is128Bit(io.vec_stu_io.in.bits.alignedType) && io.vec_stu_io.in.valid && s0_vec_iss_select
340
341  // for store
342  io.stu_io.dcache.req.valid             := s0_valid && s0_dcache_ready && !s0_ld_flow && !s0_prf
343  io.stu_io.dcache.req.bits.cmd          := MemoryOpConstants.M_PFW
344  io.stu_io.dcache.req.bits.vaddr        := s0_vaddr
345  io.stu_io.dcache.req.bits.instrtype    := Mux(s0_prf, DCACHE_PREFETCH_SOURCE.U, STORE_SOURCE.U)
346
347  // load flow priority mux
348  def fromNullSource() = {
349    s0_vaddr         := 0.U
350    s0_mask          := 0.U
351    s0_uop           := 0.U.asTypeOf(new DynInst)
352    s0_try_l2l       := false.B
353    s0_has_rob_entry := false.B
354    s0_rep_carry     := 0.U.asTypeOf(s0_rep_carry.cloneType)
355    s0_mshrid        := 0.U
356    s0_isFirstIssue  := false.B
357    s0_fast_rep      := false.B
358    s0_ld_rep        := false.B
359    s0_l2l_fwd       := false.B
360    s0_prf           := false.B
361    s0_prf_rd        := false.B
362    s0_prf_wr        := false.B
363    s0_sched_idx     := 0.U
364  }
365
366  def fromFastReplaySource(src: LqWriteBundle) = {
367    s0_vaddr         := src.vaddr
368    s0_mask          := src.mask
369    s0_uop           := src.uop
370    s0_try_l2l       := false.B
371    s0_has_rob_entry := src.hasROBEntry
372    s0_rep_carry     := src.rep_info.rep_carry
373    s0_mshrid        := src.rep_info.mshr_id
374    s0_isFirstIssue  := false.B
375    s0_fast_rep      := true.B
376    s0_ld_rep        := src.isLoadReplay
377    s0_l2l_fwd       := false.B
378    s0_prf           := LSUOpType.isPrefetch(src.uop.fuOpType)
379    s0_prf_rd        := src.uop.fuOpType === LSUOpType.prefetch_r
380    s0_prf_wr        := src.uop.fuOpType === LSUOpType.prefetch_w
381    s0_sched_idx     := src.schedIndex
382  }
383
384  def fromNormalReplaySource(src: LsPipelineBundle) = {
385    s0_vaddr         := src.vaddr
386    s0_mask          := genVWmask(src.vaddr, src.uop.fuOpType(1, 0))
387    s0_uop           := src.uop
388    s0_try_l2l       := false.B
389    s0_has_rob_entry := true.B
390    s0_rep_carry     := src.replayCarry
391    s0_mshrid        := src.mshrid
392    s0_isFirstIssue  := false.B
393    s0_fast_rep      := false.B
394    s0_ld_rep        := true.B
395    s0_l2l_fwd       := false.B
396    s0_prf           := LSUOpType.isPrefetch(src.uop.fuOpType)
397    s0_prf_rd        := src.uop.fuOpType === LSUOpType.prefetch_r
398    s0_prf_wr        := src.uop.fuOpType === LSUOpType.prefetch_w
399    s0_sched_idx     := src.schedIndex
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_rep_carry     := 0.U.asTypeOf(s0_rep_carry.cloneType)
409    s0_mshrid        := 0.U
410    s0_isFirstIssue  := false.B
411    s0_fast_rep      := false.B
412    s0_ld_rep        := false.B
413    s0_l2l_fwd       := false.B
414    s0_prf           := true.B
415    s0_prf_rd        := !src.is_store
416    s0_prf_wr        := src.is_store
417    s0_sched_idx     := 0.U
418  }
419
420  def fromIntIssueSource(src: MemExuInput) = {
421    s0_vaddr         := src.src(0) + SignExt(src.uop.imm(11, 0), VAddrBits)
422    s0_mask          := genVWmask(s0_vaddr, src.uop.fuOpType(1,0))
423    s0_uop           := src.uop
424    s0_try_l2l       := false.B
425    s0_has_rob_entry := true.B
426    s0_rep_carry     := 0.U.asTypeOf(s0_rep_carry.cloneType)
427    s0_mshrid        := 0.U
428    s0_isFirstIssue  := true.B
429    s0_fast_rep      := false.B
430    s0_ld_rep        := false.B
431    s0_l2l_fwd       := false.B
432    s0_prf           := LSUOpType.isPrefetch(src.uop.fuOpType)
433    s0_prf_rd        := src.uop.fuOpType === LSUOpType.prefetch_r
434    s0_prf_wr        := src.uop.fuOpType === LSUOpType.prefetch_w
435    s0_sched_idx     := 0.U
436  }
437
438  def fromVecIssueSource(src: VecPipeBundle) = {
439    // For now, vector port handles only vector store flows
440    s0_vaddr         := src.vaddr
441    s0_mask          := src.mask
442    s0_uop           := src.uop
443    s0_try_l2l       := false.B
444    s0_has_rob_entry := true.B
445    s0_rep_carry     := 0.U.asTypeOf(s0_rep_carry.cloneType)
446    s0_mshrid        := 0.U
447    // s0_isFirstIssue  := src.isFirstIssue
448    s0_fast_rep      := false.B
449    s0_ld_rep        := false.B
450    s0_l2l_fwd       := false.B
451    s0_prf           := false.B
452    s0_prf_rd        := false.B
453    s0_prf_wr        := false.B
454    s0_sched_idx     := 0.U
455
456    s0_isvec         := true.B
457    s0_vecActive           := io.vec_stu_io.in.bits.vecActive
458    // s0_flowPtr       := io.vec_stu_io.in.bits.flowPtr
459    // s0_isLastElem    := io.vec_stu_io.in.bits.isLastElem
460  }
461
462  def fromLoadToLoadSource(src: LoadToLoadIO) = {
463    s0_vaddr              := Cat(src.data(XLEN-1, 6), s0_ptr_chasing_vaddr(5,0))
464    s0_mask               := genVWmask(s0_vaddr, io.ldu_io.ld_fast_fuOpType(1, 0))
465    // When there's no valid instruction from RS and LSQ, we try the load-to-load forwarding.
466    // Assume the pointer chasing is always ld.
467    s0_uop.fuOpType  := io.ldu_io.ld_fast_fuOpType
468    s0_try_l2l            := true.B
469    // we dont care s0_isFirstIssue and s0_rsIdx and s0_sqIdx in S0 when trying pointchasing
470    // because these signals will be updated in S1
471    s0_has_rob_entry      := false.B
472    s0_mshrid             := 0.U
473    s0_rep_carry          := 0.U.asTypeOf(s0_rep_carry.cloneType)
474    s0_isFirstIssue       := true.B
475    s0_fast_rep           := false.B
476    s0_ld_rep             := false.B
477    s0_l2l_fwd            := true.B
478    s0_prf                := false.B
479    s0_prf_rd             := false.B
480    s0_prf_wr             := false.B
481    s0_sched_idx          := 0.U
482  }
483
484  // set default
485  s0_uop := DontCare
486  when (s0_super_ld_rep_select)      { fromNormalReplaySource(io.ldu_io.replay.bits)     }
487  .elsewhen (s0_ld_fast_rep_select)  { fromFastReplaySource(io.ldu_io.fast_rep_in.bits)  }
488  .elsewhen (s0_ld_rep_select)       { fromNormalReplaySource(io.ldu_io.replay.bits)     }
489  .elsewhen (s0_hw_prf_select)       { fromPrefetchSource(io.ldu_io.prefetch_req.bits)   }
490  .elsewhen (s0_int_iss_select)      { fromIntIssueSource(io.lsin.bits)                  }
491  .elsewhen (s0_vec_iss_select)      { fromVecIssueSource(io.vec_stu_io.in.bits)         }
492  .otherwise {
493    if (EnableLoadToLoadForward) {
494      fromLoadToLoadSource(io.ldu_io.l2l_fwd_in)
495    } else {
496      fromNullSource()
497    }
498  }
499
500  // address align check
501  val s0_addr_aligned = LookupTree(Mux(s0_isvec, io.vec_stu_io.in.bits.alignedType(1,0), s0_uop.fuOpType(1, 0)), List(
502    "b00".U   -> true.B,                   //b
503    "b01".U   -> (s0_vaddr(0)    === 0.U), //h
504    "b10".U   -> (s0_vaddr(1, 0) === 0.U), //w
505    "b11".U   -> (s0_vaddr(2, 0) === 0.U)  //d
506  ))// may broken if use it in feature
507
508  // accept load flow if dcache ready (tlb is always ready)
509  // TODO: prefetch need writeback to loadQueueFlag
510  s0_out               := DontCare
511  s0_out.vaddr         := s0_vaddr
512  s0_out.mask          := s0_mask
513  s0_out.uop           := s0_uop
514  s0_out.isFirstIssue  := s0_isFirstIssue
515  s0_out.hasROBEntry   := s0_has_rob_entry
516  s0_out.isPrefetch    := s0_prf
517  s0_out.isHWPrefetch  := s0_hw_prf
518  s0_out.isFastReplay  := s0_fast_rep
519  s0_out.isLoadReplay  := s0_ld_rep
520  s0_out.isFastPath    := s0_l2l_fwd
521  s0_out.mshrid        := s0_mshrid
522  s0_out.isvec         := s0_isvec
523  s0_out.isLastElem    := s0_isLastElem
524  s0_out.vecActive           := s0_vecActive
525  // s0_out.sflowPtr      := s0_flowPtr
526  s0_out.uop.exceptionVec(loadAddrMisaligned)  := !s0_addr_aligned && s0_ld_flow
527  s0_out.uop.exceptionVec(storeAddrMisaligned) := !s0_addr_aligned && !s0_ld_flow
528  s0_out.forward_tlDchannel := s0_super_ld_rep_select
529  when(io.tlb.req.valid && s0_isFirstIssue) {
530    s0_out.uop.debugInfo.tlbFirstReqTime := GTimer()
531  }.otherwise{
532    s0_out.uop.debugInfo.tlbFirstReqTime := s0_uop.debugInfo.tlbFirstReqTime
533  }
534  s0_out.schedIndex     := s0_sched_idx
535
536  // load fast replay
537  io.ldu_io.fast_rep_in.ready := (s0_can_go && io.ldu_io.dcache.req.ready && s0_ld_fast_rep_ready)
538
539  // load flow source ready
540  // cache missed load has highest priority
541  // always accept cache missed load flow from load replay queue
542  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))
543
544  // accept load flow from rs when:
545  // 1) there is no lsq-replayed load
546  // 2) there is no fast replayed load
547  // 3) there is no high confidence prefetch request
548  io.lsin.ready := (s0_can_go &&
549                    Mux(FuType.isLoad(io.lsin.bits.uop.fuType), io.ldu_io.dcache.req.ready,
550                    (if (StorePrefetchL1Enabled) io.stu_io.dcache.req.ready else true.B)) && s0_int_iss_ready)
551  io.vec_stu_io.in.ready := s0_can_go && io.ldu_io.dcache.req.ready && s0_vec_iss_ready
552
553
554  // for hw prefetch load flow feedback, to be added later
555  // io.prefetch_in.ready := s0_hw_prf_select
556
557  // dcache replacement extra info
558  // TODO: should prefetch load update replacement?
559  io.ldu_io.dcache.replacementUpdated := Mux(s0_ld_rep_select || s0_super_ld_rep_select, io.ldu_io.replay.bits.replacementUpdated, false.B)
560
561  io.stu_io.prefetch_req.ready := s1_ready && io.stu_io.dcache.req.ready && !io.lsin.valid
562
563  // load debug
564  XSDebug(io.ldu_io.dcache.req.fire && s0_ld_flow,
565    p"[DCACHE LOAD REQ] pc ${Hexadecimal(s0_uop.pc)}, vaddr ${Hexadecimal(s0_vaddr)}\n"
566  )
567  XSDebug(s0_valid && s0_ld_flow,
568    p"S0: pc ${Hexadecimal(s0_out.uop.pc)}, lqIdx ${Hexadecimal(s0_out.uop.lqIdx.asUInt)}, " +
569    p"vaddr ${Hexadecimal(s0_out.vaddr)}, mask ${Hexadecimal(s0_out.mask)}\n")
570
571  // store debug
572  XSDebug(io.stu_io.dcache.req.fire && !s0_ld_flow,
573    p"[DCACHE STORE 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)}, sqIdx ${Hexadecimal(s0_out.uop.sqIdx.asUInt)}, " +
577    p"vaddr ${Hexadecimal(s0_out.vaddr)}, mask ${Hexadecimal(s0_out.mask)}\n")
578
579
580  // Pipeline
581  // --------------------------------------------------------------------------------
582  // stage 1
583  // --------------------------------------------------------------------------------
584  // TLB resp (send paddr to dcache)
585  val s1_valid      = RegInit(false.B)
586  val s1_in         = Wire(new LqWriteBundle)
587  val s1_out        = Wire(new LqWriteBundle)
588  val s1_kill       = Wire(Bool())
589  val s1_can_go     = s2_ready
590  val s1_fire       = s1_valid && !s1_kill && s1_can_go
591  val s1_ld_flow    = RegNext(s0_ld_flow)
592  val s1_isvec      = RegEnable(s0_out.isvec, false.B, s0_fire)
593  val s1_isLastElem = RegEnable(s0_out.isLastElem, false.B, s0_fire)
594
595  s1_ready := !s1_valid || s1_kill || s2_ready
596  when (s0_fire) { s1_valid := true.B }
597  .elsewhen (s1_fire) { s1_valid := false.B }
598  .elsewhen (s1_kill) { s1_valid := false.B }
599  s1_in   := RegEnable(s0_out, s0_fire)
600
601  val s1_fast_rep_dly_err = RegNext(io.ldu_io.fast_rep_in.bits.delayedLoadError)
602  val s1_fast_rep_kill    = s1_fast_rep_dly_err && s1_in.isFastReplay
603  val s1_l2l_fwd_dly_err  = RegNext(io.ldu_io.l2l_fwd_in.dly_ld_err)
604  val s1_l2l_fwd_kill     = s1_l2l_fwd_dly_err && s1_in.isFastPath
605  val s1_late_kill        = s1_fast_rep_kill || s1_l2l_fwd_kill
606  val s1_vaddr_hi         = Wire(UInt())
607  val s1_vaddr_lo         = Wire(UInt())
608  val s1_vaddr            = Wire(UInt())
609  val s1_paddr_dup_lsu    = Wire(UInt())
610  val s1_paddr_dup_dcache = Wire(UInt())
611  val s1_ld_exception     = ExceptionNO.selectByFu(s1_out.uop.exceptionVec, LduCfg).asUInt.orR   // af & pf exception were modified below.
612  val s1_st_exception     = ExceptionNO.selectByFu(s1_out.uop.exceptionVec, StaCfg).asUInt.orR   // af & pf exception were modified below.
613  val s1_exception        = (s1_ld_flow && s1_ld_exception) || (!s1_ld_flow && s1_st_exception)
614  val s1_tlb_miss         = io.tlb.resp.bits.miss
615  val s1_prf              = s1_in.isPrefetch
616  val s1_hw_prf           = s1_in.isHWPrefetch
617  val s1_sw_prf           = s1_prf && !s1_hw_prf
618  val s1_tlb_memidx       = io.tlb.resp.bits.memidx
619
620  // mmio cbo decoder
621  val s1_mmio_cbo  = (s1_in.uop.fuOpType === LSUOpType.cbo_clean ||
622                      s1_in.uop.fuOpType === LSUOpType.cbo_flush ||
623                      s1_in.uop.fuOpType === LSUOpType.cbo_inval) && !s1_ld_flow && !s1_prf
624  val s1_mmio = s1_mmio_cbo
625
626  s1_vaddr_hi         := s1_in.vaddr(VAddrBits - 1, 6)
627  s1_vaddr_lo         := s1_in.vaddr(5, 0)
628  s1_vaddr            := Cat(s1_vaddr_hi, s1_vaddr_lo)
629  s1_paddr_dup_lsu    := io.tlb.resp.bits.paddr(0)
630  s1_paddr_dup_dcache := io.tlb.resp.bits.paddr(1)
631
632  when (s1_tlb_memidx.is_ld && io.tlb.resp.valid && !s1_tlb_miss &&
633        s1_tlb_memidx.idx === s1_in.uop.lqIdx.value && s1_ld_flow) {
634    // printf("Load idx = %d\n", s1_tlb_memidx.idx)
635    s1_out.uop.debugInfo.tlbRespTime := GTimer()
636  } .elsewhen(s1_tlb_memidx.is_st && io.tlb.resp.valid && !s1_tlb_miss &&
637              s1_tlb_memidx.idx === s1_out.uop.sqIdx.value && !s1_ld_flow) {
638    // printf("Store idx = %d\n", s1_tlb_memidx.idx)
639    s1_out.uop.debugInfo.tlbRespTime := GTimer()
640  }
641
642  io.tlb.req_kill   := s1_kill
643  io.tlb.resp.ready := true.B
644
645  io.ldu_io.dcache.s1_paddr_dup_lsu    <> s1_paddr_dup_lsu
646  io.ldu_io.dcache.s1_paddr_dup_dcache <> s1_paddr_dup_dcache
647  io.ldu_io.dcache.s1_kill             := s1_kill || s1_tlb_miss || s1_exception
648
649  // store to load forwarding
650  io.ldu_io.sbuffer.valid := s1_valid && !(s1_exception || s1_tlb_miss || s1_kill || s1_fast_rep_kill || s1_prf || !s1_ld_flow)
651  io.ldu_io.sbuffer.vaddr := s1_vaddr
652  io.ldu_io.sbuffer.paddr := s1_paddr_dup_lsu
653  io.ldu_io.sbuffer.uop   := s1_in.uop
654  io.ldu_io.sbuffer.sqIdx := s1_in.uop.sqIdx
655  io.ldu_io.sbuffer.mask  := s1_in.mask
656  io.ldu_io.sbuffer.pc    := s1_in.uop.pc // FIXME: remove it
657
658  io.ldu_io.vec_forward.valid := s1_valid && !(s1_exception || s1_tlb_miss || s1_kill || s1_fast_rep_kill || s1_prf || !s1_ld_flow)
659  io.ldu_io.vec_forward.vaddr := s1_vaddr
660  io.ldu_io.vec_forward.paddr := s1_paddr_dup_lsu
661  io.ldu_io.vec_forward.uop   := s1_in.uop
662  io.ldu_io.vec_forward.sqIdx := s1_in.uop.sqIdx
663  io.ldu_io.vec_forward.mask  := s1_in.mask
664  io.ldu_io.vec_forward.pc    := s1_in.uop.pc // FIXME: remove it
665
666  io.ldu_io.lsq.forward.valid     := s1_valid && !(s1_exception || s1_tlb_miss || s1_kill || s1_fast_rep_kill || s1_prf || !s1_ld_flow)
667  io.ldu_io.lsq.forward.vaddr     := s1_vaddr
668  io.ldu_io.lsq.forward.paddr     := s1_paddr_dup_lsu
669  io.ldu_io.lsq.forward.uop       := s1_in.uop
670  io.ldu_io.lsq.forward.sqIdx     := s1_in.uop.sqIdx
671  io.ldu_io.lsq.forward.sqIdxMask := 0.U
672  io.ldu_io.lsq.forward.mask      := s1_in.mask
673  io.ldu_io.lsq.forward.pc        := s1_in.uop.pc // FIXME: remove it
674
675  // st-ld violation query
676  val s1_nuke = VecInit((0 until StorePipelineWidth).map(w => {
677                       io.ldu_io.stld_nuke_query(w).valid && // query valid
678                       isAfter(s1_in.uop.robIdx, io.ldu_io.stld_nuke_query(w).bits.robIdx) && // older store
679                       // TODO: Fix me when vector instruction
680                       (s1_paddr_dup_lsu(PAddrBits-1, 3) === io.ldu_io.stld_nuke_query(w).bits.paddr(PAddrBits-1, 3)) && // paddr match
681                       (s1_in.mask & io.ldu_io.stld_nuke_query(w).bits.mask).orR // data mask contain
682                      })).asUInt.orR && !s1_tlb_miss && s1_ld_flow
683
684  s1_out                   := s1_in
685  s1_out.vaddr             := s1_vaddr
686  s1_out.paddr             := s1_paddr_dup_lsu
687  s1_out.tlbMiss           := s1_tlb_miss
688  s1_out.ptwBack           := io.tlb.resp.bits.ptwBack
689  s1_out.rep_info.debug    := s1_in.uop.debugInfo
690  s1_out.rep_info.nuke     := s1_nuke && !s1_sw_prf
691  s1_out.lateKill          := s1_late_kill
692
693  when (s1_ld_flow) {
694    when (!s1_late_kill) {
695      // current ori test will cause the case of ldest == 0, below will be modifeid in the future.
696      // af & pf exception were modified
697      s1_out.uop.exceptionVec(loadPageFault)       := io.tlb.resp.bits.excp(0).pf.ld
698      s1_out.uop.exceptionVec(loadGuestPageFault)  := io.tlb.resp.bits.excp(0).gpf.ld
699      s1_out.uop.exceptionVec(loadAccessFault)     := io.tlb.resp.bits.excp(0).af.ld
700    } .otherwise {
701      s1_out.uop.exceptionVec(loadAddrMisaligned)  := false.B
702      s1_out.uop.exceptionVec(loadAccessFault)     := s1_late_kill
703    }
704  } .otherwise {
705    s1_out.uop.exceptionVec(storePageFault)        := io.tlb.resp.bits.excp(0).pf.st
706    s1_out.uop.exceptionVec(storeGuestPageFault)   := io.tlb.resp.bits.excp(0).gpf.st
707    s1_out.uop.exceptionVec(storeAccessFault)      := io.tlb.resp.bits.excp(0).af.st
708  }
709
710  // pointer chasing
711  val s1_try_ptr_chasing       = RegNext(s0_do_try_ptr_chasing, false.B)
712  val s1_ptr_chasing_vaddr     = RegEnable(s0_ptr_chasing_vaddr, s0_do_try_ptr_chasing)
713  val s1_fu_op_type_not_ld     = WireInit(false.B)
714  val s1_not_fast_match        = WireInit(false.B)
715  val s1_addr_mismatch         = WireInit(false.B)
716  val s1_addr_misaligned       = WireInit(false.B)
717  val s1_ptr_chasing_canceled  = WireInit(false.B)
718  val s1_cancel_ptr_chasing    = WireInit(false.B)
719
720  s1_kill := s1_late_kill ||
721             s1_cancel_ptr_chasing ||
722             s1_in.uop.robIdx.needFlush(io.redirect) ||
723             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)
724
725  if (EnableLoadToLoadForward) {
726    // Sometimes, we need to cancel the load-load forwarding.
727    // These can be put at S0 if timing is bad at S1.
728    // Case 0: CACHE_SET(base + offset) != CACHE_SET(base) (lowest 6-bit addition has an overflow)
729    s1_addr_mismatch      := s1_ptr_chasing_vaddr(6) || RegEnable(io.ldu_io.ld_fast_imm(11, 6).orR, s0_do_try_ptr_chasing)
730    // Case 1: the address is misaligned, kill s1
731    s1_addr_misaligned    := LookupTree(s1_in.uop.fuOpType(1, 0), List(
732                             "b00".U   -> false.B,                  //b
733                             "b01".U   -> (s1_vaddr(0)    =/= 0.U), //h
734                             "b10".U   -> (s1_vaddr(1, 0) =/= 0.U), //w
735                             "b11".U   -> (s1_vaddr(2, 0) =/= 0.U)  //d
736                          ))
737    // Case 2: this load-load uop is cancelled
738    s1_ptr_chasing_canceled := !io.lsin.valid || FuType.isStore(io.lsin.bits.uop.fuType)
739
740    when (s1_try_ptr_chasing) {
741      s1_cancel_ptr_chasing := s1_addr_mismatch || s1_addr_misaligned || s1_ptr_chasing_canceled
742
743      s1_in.uop           := io.lsin.bits.uop
744      s1_in.isFirstIssue  := io.lsin.bits.isFirstIssue
745      s1_vaddr_lo         := s1_ptr_chasing_vaddr(5, 0)
746      s1_paddr_dup_lsu    := Cat(io.tlb.resp.bits.paddr(0)(PAddrBits - 1, 6), s1_vaddr_lo)
747      s1_paddr_dup_dcache := Cat(io.tlb.resp.bits.paddr(0)(PAddrBits - 1, 6), s1_vaddr_lo)
748
749      // 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)
750      s1_in.uop.debugInfo.tlbFirstReqTime := GTimer()
751      s1_in.uop.debugInfo.tlbRespTime     := GTimer()
752    }
753    when (!s1_cancel_ptr_chasing) {
754      s0_ptr_chasing_canceled := s1_try_ptr_chasing && !io.ldu_io.replay.fire && !io.ldu_io.fast_rep_in.fire && !(s0_high_conf_prf_valid && io.canAcceptHighConfPrefetch)
755      when (s1_try_ptr_chasing) {
756        io.lsin.ready := true.B
757      }
758    }
759  }
760
761  // pre-calcuate sqIdx mask in s0, then send it to lsq in s1 for forwarding
762  val s1_sqIdx_mask = RegNext(UIntToMask(s0_out.uop.sqIdx.value, StoreQueueSize))
763  // to enable load-load, sqIdxMask must be calculated based on lsin.uop
764  // If the timing here is not OK, load-load forwarding has to be disabled.
765  // Or we calculate sqIdxMask at RS??
766  io.ldu_io.lsq.forward.sqIdxMask := s1_sqIdx_mask
767  if (EnableLoadToLoadForward) {
768    when (s1_try_ptr_chasing) {
769      io.ldu_io.lsq.forward.sqIdxMask := UIntToMask(io.lsin.bits.uop.sqIdx.value, StoreQueueSize)
770    }
771  }
772
773  io.ldu_io.forward_mshr.valid  := s1_valid && s1_out.forward_tlDchannel && s1_ld_flow
774  io.ldu_io.forward_mshr.mshrid := s1_out.mshrid
775  io.ldu_io.forward_mshr.paddr  := s1_out.paddr
776
777  io.ldu_io.wakeup.valid := s0_fire && s0_ld_flow && (s0_super_ld_rep_select || s0_ld_fast_rep_select || s0_ld_rep_select || s0_int_iss_select)
778  io.ldu_io.wakeup.bits := s0_uop
779
780  io.stu_io.dcache.s1_kill := s1_tlb_miss || s1_exception || s1_mmio || s1_in.uop.robIdx.needFlush(io.redirect)
781  io.stu_io.dcache.s1_paddr := s1_paddr_dup_dcache
782
783
784  // load debug
785  XSDebug(s1_valid && s1_ld_flow,
786    p"S1: pc ${Hexadecimal(s1_out.uop.pc)}, lId ${Hexadecimal(s1_out.uop.lqIdx.asUInt)}, tlb_miss ${io.tlb.resp.bits.miss}, " +
787    p"paddr ${Hexadecimal(s1_out.paddr)}, mmio ${s1_out.mmio}\n")
788
789  // store debug
790  XSDebug(s1_valid && !s1_ld_flow,
791    p"S1: pc ${Hexadecimal(s1_out.uop.pc)}, lId ${Hexadecimal(s1_out.uop.sqIdx.asUInt)}, tlb_miss ${io.tlb.resp.bits.miss}, " +
792    p"paddr ${Hexadecimal(s1_out.paddr)}, mmio ${s1_out.mmio}\n")
793
794  // store out
795  io.stu_io.lsq.valid         := s1_valid && !s1_ld_flow && !s1_prf && !s1_isvec
796  io.stu_io.lsq.bits          := s1_out
797  io.stu_io.lsq.bits.miss     := s1_tlb_miss
798
799  io.vec_stu_io.lsq.valid     := s1_valid && !s1_ld_flow && !s1_prf && s1_isvec
800  io.vec_stu_io.lsq.bits          := s1_out
801  io.vec_stu_io.lsq.bits.miss     := s1_tlb_miss
802  io.vec_stu_io.lsq.bits.isLastElem := s1_isLastElem
803
804  io.stu_io.st_mask_out.valid       := s1_valid && !s1_ld_flow && !s1_prf
805  io.stu_io.st_mask_out.bits.mask   := s1_out.mask
806  io.stu_io.st_mask_out.bits.sqIdx  := s1_out.uop.sqIdx
807
808  io.stu_io.issue.valid       := s1_valid && !s1_tlb_miss && !s1_ld_flow && !s1_prf && !s1_isvec
809  io.stu_io.issue.bits        := RegEnable(io.lsin.bits, io.lsin.fire)
810
811  // st-ld violation dectect request
812  io.stu_io.stld_nuke_query.valid       := s1_valid && !s1_tlb_miss && !s1_ld_flow && !s1_prf
813  io.stu_io.stld_nuke_query.bits.robIdx := s1_in.uop.robIdx
814  io.stu_io.stld_nuke_query.bits.paddr  := s1_paddr_dup_lsu
815  io.stu_io.stld_nuke_query.bits.mask   := s1_in.mask
816
817  // Pipeline
818  // --------------------------------------------------------------------------------
819  // stage 2
820  // --------------------------------------------------------------------------------
821  // s2: DCache resp
822  val s2_valid  = RegInit(false.B)
823  val s2_in     = Wire(new LqWriteBundle)
824  val s2_out    = Wire(new LqWriteBundle)
825  val s2_kill   = Wire(Bool())
826  val s2_can_go = s3_ready
827  val s2_fire   = s2_valid && !s2_kill && s2_can_go
828  val s2_isvec  = RegEnable(s1_isvec, false.B, s1_fire)
829  val s2_vecActive    = RegEnable(s1_out.vecActive, true.B, s1_fire)
830  val s2_paddr  = RegEnable(s1_paddr_dup_lsu, s1_fire)
831
832  s2_kill := s2_in.uop.robIdx.needFlush(io.redirect)
833  s2_ready := !s2_valid || s2_kill || s3_ready
834  when (s1_fire) { s2_valid := true.B }
835  .elsewhen (s2_fire) { s2_valid := false.B }
836  .elsewhen (s2_kill) { s2_valid := false.B }
837  s2_in := RegEnable(s1_out, s1_fire)
838
839  val s2_pmp = WireInit(io.pmp)
840
841  val s2_prf    = s2_in.isPrefetch
842  val s2_hw_prf = s2_in.isHWPrefetch
843  val s2_ld_flow  = RegEnable(s1_ld_flow, s1_fire)
844
845  // exception that may cause load addr to be invalid / illegal
846  // if such exception happen, that inst and its exception info
847  // will be force writebacked to rob
848  val s2_exception_vec = WireInit(s2_in.uop.exceptionVec)
849  when (s2_ld_flow) {
850    when (!s2_in.lateKill) {
851      s2_exception_vec(loadAccessFault) := (s2_in.uop.exceptionVec(loadAccessFault) || s2_pmp.ld) && s2_vecActive
852      // soft prefetch will not trigger any exception (but ecc error interrupt may be triggered)
853      when (s2_prf || s2_in.tlbMiss) {
854        s2_exception_vec := 0.U.asTypeOf(s2_exception_vec.cloneType)
855      }
856    }
857  } .otherwise {
858    s2_exception_vec(storeAccessFault) := s2_in.uop.exceptionVec(storeAccessFault) || s2_pmp.st
859    when (s2_prf || s2_in.tlbMiss) {
860      s2_exception_vec := 0.U.asTypeOf(s2_exception_vec.cloneType)
861    }
862  }
863  val s2_ld_exception = ExceptionNO.selectByFu(s2_exception_vec, LduCfg).asUInt.orR && s2_ld_flow
864  val s2_st_exception = ExceptionNO.selectByFu(s2_exception_vec, StaCfg).asUInt.orR && !s2_ld_flow
865  val s2_exception    = s2_ld_exception || s2_st_exception
866
867  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)
868  val (s2_fwd_data_valid, s2_fwd_frm_mshr, s2_fwd_data_frm_mshr) = io.ldu_io.forward_mshr.forward()
869  val s2_fwd_frm_d_chan_or_mshr = s2_fwd_data_valid && (s2_fwd_frm_d_chan || s2_fwd_frm_mshr)
870
871  // writeback access fault caused by ecc error / bus error
872  // * ecc data error is slow to generate, so we will not use it until load stage 3
873  // * in load stage 3, an extra signal io.load_error will be used to
874  val s2_actually_mmio = s2_pmp.mmio
875  val s2_ld_mmio       = !s2_prf &&
876                          s2_actually_mmio &&
877                         !s2_exception &&
878                         !s2_in.tlbMiss &&
879                         s2_ld_flow
880  val s2_st_mmio       = !s2_prf &&
881                          (RegNext(s1_mmio) || s2_pmp.mmio) &&
882                         !s2_exception &&
883                         !s2_in.tlbMiss &&
884                         !s2_ld_flow
885  val s2_st_atomic     = !s2_prf &&
886                          (RegNext(s1_mmio) || s2_pmp.atomic) &&
887                         !s2_exception &&
888                         !s2_in.tlbMiss &&
889                         !s2_ld_flow
890  val s2_full_fwd      = Wire(Bool())
891  val s2_mem_amb       = s2_in.uop.storeSetHit &&
892                         io.ldu_io.lsq.forward.addrInvalid
893
894  val s2_tlb_miss      = s2_in.tlbMiss
895  val s2_fwd_fail      = io.ldu_io.lsq.forward.dataInvalid || io.ldu_io.vec_forward.dataInvalid
896  val s2_dcache_miss   = io.ldu_io.dcache.resp.bits.miss &&
897                         !s2_fwd_frm_d_chan_or_mshr &&
898                         !s2_full_fwd
899
900  val s2_mq_nack       = io.ldu_io.dcache.s2_mq_nack &&
901                         !s2_fwd_frm_d_chan_or_mshr &&
902                         !s2_full_fwd
903
904  val s2_bank_conflict = io.ldu_io.dcache.s2_bank_conflict &&
905                         !s2_fwd_frm_d_chan_or_mshr &&
906                         !s2_full_fwd
907
908  val s2_wpu_pred_fail = io.ldu_io.dcache.s2_wpu_pred_fail &&
909                        !s2_fwd_frm_d_chan_or_mshr &&
910                        !s2_full_fwd
911
912  val s2_rar_nack      = io.ldu_io.lsq.ldld_nuke_query.req.valid &&
913                         !io.ldu_io.lsq.ldld_nuke_query.req.ready
914
915  val s2_raw_nack      = io.ldu_io.lsq.stld_nuke_query.req.valid &&
916                         !io.ldu_io.lsq.stld_nuke_query.req.ready
917
918  // st-ld violation query
919  //  NeedFastRecovery Valid when
920  //  1. Fast recovery query request Valid.
921  //  2. Load instruction is younger than requestors(store instructions).
922  //  3. Physical address match.
923  //  4. Data contains.
924  val s2_nuke = VecInit((0 until StorePipelineWidth).map(w => {
925                        io.ldu_io.stld_nuke_query(w).valid && // query valid
926                        isAfter(s2_in.uop.robIdx, io.ldu_io.stld_nuke_query(w).bits.robIdx) && // older store
927                        // TODO: Fix me when vector instruction
928                        (s2_in.paddr(PAddrBits-1, 3) === io.ldu_io.stld_nuke_query(w).bits.paddr(PAddrBits-1, 3)) && // paddr match
929                        (s2_in.mask & io.ldu_io.stld_nuke_query(w).bits.mask).orR // data mask contain
930                      })).asUInt.orR && s2_ld_flow || s2_in.rep_info.nuke
931
932  val s2_cache_handled   = io.ldu_io.dcache.resp.bits.handled
933  val s2_cache_tag_error = RegNext(io.csrCtrl.cache_error_enable) &&
934                           io.ldu_io.dcache.resp.bits.tag_error
935
936  val s2_troublem        = !s2_exception &&
937                           !s2_ld_mmio &&
938                           !s2_prf &&
939                           !s2_in.lateKill &&
940                           s2_ld_flow
941
942  io.ldu_io.dcache.resp.ready := true.B
943  io.stu_io.dcache.resp.ready := true.B
944  val s2_dcache_should_resp = !(s2_in.tlbMiss || s2_exception || s2_ld_mmio || s2_prf || s2_in.lateKill) && s2_ld_flow
945  assert(!(s2_valid && (s2_dcache_should_resp && !io.ldu_io.dcache.resp.valid)), "DCache response got lost")
946
947  // fast replay require
948  val s2_dcache_fast_rep = (s2_mq_nack || !s2_dcache_miss && (s2_bank_conflict || s2_wpu_pred_fail))
949  val s2_nuke_fast_rep   = !s2_mq_nack &&
950                           !s2_dcache_miss &&
951                           !s2_bank_conflict &&
952                           !s2_wpu_pred_fail &&
953                           !s2_rar_nack &&
954                           !s2_raw_nack &&
955                           s2_nuke
956
957  val s2_fast_rep = !s2_mem_amb &&
958                    !s2_tlb_miss &&
959                    !s2_fwd_fail &&
960                    (s2_dcache_fast_rep || s2_nuke_fast_rep) &&
961                    s2_troublem
962
963  // need allocate new entry
964  val s2_can_query = !s2_mem_amb &&
965                     !s2_tlb_miss  &&
966                     !s2_fwd_fail &&
967                     !s2_dcache_fast_rep &&
968                     s2_troublem
969
970  val s2_data_fwded = s2_dcache_miss && (s2_full_fwd || s2_cache_tag_error)
971
972  // ld-ld violation require
973  io.ldu_io.lsq.ldld_nuke_query.req.valid           := s2_valid && s2_can_query
974  io.ldu_io.lsq.ldld_nuke_query.req.bits.uop        := s2_in.uop
975  io.ldu_io.lsq.ldld_nuke_query.req.bits.mask       := s2_in.mask
976  io.ldu_io.lsq.ldld_nuke_query.req.bits.paddr      := s2_in.paddr
977  io.ldu_io.lsq.ldld_nuke_query.req.bits.data_valid := Mux(s2_full_fwd || s2_fwd_data_valid, true.B, !s2_dcache_miss)
978
979  // st-ld violation require
980  io.ldu_io.lsq.stld_nuke_query.req.valid           := s2_valid && s2_can_query
981  io.ldu_io.lsq.stld_nuke_query.req.bits.uop        := s2_in.uop
982  io.ldu_io.lsq.stld_nuke_query.req.bits.mask       := s2_in.mask
983  io.ldu_io.lsq.stld_nuke_query.req.bits.paddr      := s2_in.paddr
984  io.ldu_io.lsq.stld_nuke_query.req.bits.data_valid := Mux(s2_full_fwd || s2_fwd_data_valid, true.B, !s2_dcache_miss)
985
986  // merge forward result
987  // lsq has higher priority than sbuffer
988  val s2_fwd_mask = Wire(Vec((VLEN/8), Bool()))
989  val s2_fwd_data = Wire(Vec((VLEN/8), UInt(8.W)))
990  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
991  // generate XLEN/8 Muxs
992  for (i <- 0 until VLEN / 8) {
993    s2_fwd_mask(i) := io.ldu_io.lsq.forward.forwardMask(i) || io.ldu_io.sbuffer.forwardMask(i) || io.ldu_io.vec_forward.forwardMask(i)
994    s2_fwd_data(i) := Mux(
995      io.ldu_io.lsq.forward.forwardMask(i),
996      io.ldu_io.lsq.forward.forwardData(i),
997      Mux(
998        io.ldu_io.vec_forward.forwardMask(i),
999        io.ldu_io.vec_forward.forwardData(i),
1000        io.ldu_io.sbuffer.forwardData(i)
1001      )
1002    )
1003  }
1004
1005  XSDebug(s2_fire && s2_ld_flow, "[FWD LOAD RESP] pc %x fwd %x(%b) + %x(%b)\n",
1006    s2_in.uop.pc,
1007    io.ldu_io.lsq.forward.forwardData.asUInt, io.ldu_io.lsq.forward.forwardMask.asUInt,
1008    s2_in.forwardData.asUInt, s2_in.forwardMask.asUInt
1009  )
1010
1011  //
1012  s2_out                  := s2_in
1013  s2_out.data             := 0.U // data will be generated in load s3
1014  s2_out.uop.fpWen        := s2_in.uop.fpWen && !s2_exception && s2_ld_flow
1015  s2_out.mmio             := s2_ld_mmio || s2_st_mmio
1016  s2_out.atomic           := s2_st_atomic
1017  s2_out.uop.flushPipe    := false.B
1018  s2_out.uop.exceptionVec := s2_exception_vec
1019  s2_out.forwardMask      := s2_fwd_mask
1020  s2_out.forwardData      := s2_fwd_data
1021  s2_out.handledByMSHR    := s2_cache_handled
1022  s2_out.miss             := s2_dcache_miss && s2_troublem
1023  s2_out.feedbacked       := io.feedback_fast.valid && !io.feedback_fast.bits.hit
1024
1025  // Generate replay signal caused by:
1026  // * st-ld violation check
1027  // * tlb miss
1028  // * dcache replay
1029  // * forward data invalid
1030  // * dcache miss
1031  s2_out.rep_info.mem_amb         := s2_mem_amb && s2_troublem
1032  s2_out.rep_info.tlb_miss        := s2_tlb_miss && s2_troublem
1033  s2_out.rep_info.fwd_fail        := s2_fwd_fail && s2_troublem
1034  s2_out.rep_info.dcache_rep      := s2_mq_nack && s2_troublem
1035  s2_out.rep_info.dcache_miss     := s2_dcache_miss && s2_troublem
1036  s2_out.rep_info.bank_conflict   := s2_bank_conflict && s2_troublem
1037  s2_out.rep_info.wpu_fail        := s2_wpu_pred_fail && s2_troublem
1038  s2_out.rep_info.rar_nack        := s2_rar_nack && s2_troublem
1039  s2_out.rep_info.raw_nack        := s2_raw_nack && s2_troublem
1040  s2_out.rep_info.nuke            := s2_nuke && s2_troublem
1041  s2_out.rep_info.full_fwd        := s2_data_fwded
1042  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)
1043  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)
1044  s2_out.rep_info.rep_carry       := io.ldu_io.dcache.resp.bits.replayCarry
1045  s2_out.rep_info.mshr_id         := io.ldu_io.dcache.resp.bits.mshr_id
1046  s2_out.rep_info.last_beat       := s2_in.paddr(log2Up(refillBytes))
1047  s2_out.rep_info.debug           := s2_in.uop.debugInfo
1048  s2_out.rep_info.tlb_id          := io.ldu_io.tlb_hint.id
1049  s2_out.rep_info.tlb_full        := io.ldu_io.tlb_hint.full
1050
1051  // if forward fail, replay this inst from fetch
1052  val debug_fwd_fail_rep = s2_fwd_fail && !s2_troublem && !s2_in.tlbMiss
1053  // if ld-ld violation is detected, replay from this inst from fetch
1054  val debug_ldld_nuke_rep = false.B // s2_ldld_violation && !s2_ld_mmio && !s2_is_prefetch && !s2_in.tlbMiss
1055  // io.out.bits.uop.replayInst := false.B
1056
1057  // to be removed
1058  val s2_ld_need_fb = !s2_in.isLoadReplay &&      // already feedbacked
1059                      io.ldu_io.lq_rep_full &&           // LoadQueueReplay is full
1060                      s2_out.rep_info.need_rep && // need replay
1061                      !s2_exception &&            // no exception is triggered
1062                      !s2_hw_prf &&               // not hardware prefetch
1063                      !s2_isvec
1064  val s2_st_need_fb = !s2_ld_flow && !s2_hw_prf && !s2_isvec
1065  io.feedback_fast.valid                 := s2_valid && (s2_ld_need_fb || s2_st_need_fb)
1066  io.feedback_fast.bits.hit              := Mux(s2_ld_flow, false.B, !s2_tlb_miss)
1067  io.feedback_fast.bits.flushState       := s2_in.ptwBack
1068  io.feedback_fast.bits.robIdx           := s2_in.uop.robIdx
1069  io.feedback_fast.bits.sourceType       := Mux(s2_ld_flow, RSFeedbackType.lrqFull, RSFeedbackType.tlbMiss)
1070  io.feedback_fast.bits.dataInvalidSqIdx := DontCare
1071
1072  val s2_vec_feedback = Wire(Valid(new VSFQFeedback))
1073  s2_vec_feedback.valid := s2_valid && !s2_ld_flow && !s2_hw_prf && s2_isvec
1074  // s2_vec_feedback.bits.flowPtr := s2_out.sflowPtr
1075  s2_vec_feedback.bits.hit := !s2_tlb_miss
1076  s2_vec_feedback.bits.sourceType := RSFeedbackType.tlbMiss
1077  s2_vec_feedback.bits.paddr := s2_paddr
1078  s2_vec_feedback.bits.mmio := s2_st_mmio
1079  s2_vec_feedback.bits.atomic := s2_st_mmio
1080  s2_vec_feedback.bits.exceptionVec := s2_exception_vec
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 := false.B
1086
1087  // fast wakeup
1088  io.ldu_io.fast_uop.valid := RegNext(
1089    !io.ldu_io.dcache.s1_disable_fast_wakeup &&
1090    s1_valid &&
1091    !s1_kill &&
1092    !io.tlb.resp.bits.miss &&
1093    !io.ldu_io.lsq.forward.dataInvalidFast
1094  ) && (s2_valid && !s2_out.rep_info.need_rep && !s2_ld_mmio && s2_ld_flow) && !s2_isvec
1095  io.ldu_io.fast_uop.bits := RegNext(s1_out.uop)
1096
1097  //
1098  io.ldu_io.s2_ptr_chasing                    := RegEnable(s1_try_ptr_chasing && !s1_cancel_ptr_chasing, false.B, s1_fire)
1099
1100  // prefetch train
1101  io.s0_prefetch_spec := s0_fire
1102  io.s1_prefetch_spec := s1_fire
1103  io.prefetch_train.valid              := s2_valid && !s2_actually_mmio && !s2_in.tlbMiss
1104  io.prefetch_train.bits.fromLsPipelineBundle(s2_in)
1105  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?
1106  io.prefetch_train.bits.meta_prefetch := Mux(s2_ld_flow, io.ldu_io.dcache.resp.bits.meta_prefetch, false.B)
1107  io.prefetch_train.bits.meta_access   := Mux(s2_ld_flow, io.ldu_io.dcache.resp.bits.meta_access, false.B)
1108
1109  io.prefetch_train_l1.valid              := s2_valid && !s2_actually_mmio && s2_ld_flow
1110  io.prefetch_train_l1.bits.fromLsPipelineBundle(s2_in)
1111  io.prefetch_train_l1.bits.miss          := io.ldu_io.dcache.resp.bits.miss
1112  io.prefetch_train_l1.bits.meta_prefetch := io.ldu_io.dcache.resp.bits.meta_prefetch
1113  io.prefetch_train_l1.bits.meta_access   := io.ldu_io.dcache.resp.bits.meta_access
1114  if (env.FPGAPlatform){
1115    io.ldu_io.dcache.s0_pc := DontCare
1116    io.ldu_io.dcache.s1_pc := DontCare
1117    io.ldu_io.dcache.s2_pc := DontCare
1118  }else{
1119    io.ldu_io.dcache.s0_pc := s0_out.uop.pc
1120    io.ldu_io.dcache.s1_pc := s1_out.uop.pc
1121    io.ldu_io.dcache.s2_pc := s2_out.uop.pc
1122  }
1123  io.ldu_io.dcache.s2_kill := s2_pmp.ld  || s2_actually_mmio || s2_kill
1124  io.stu_io.dcache.s2_kill := s2_pmp.st || s2_actually_mmio || s2_kill
1125  io.stu_io.dcache.s2_pc := s2_out.uop.pc
1126
1127  val s1_ld_left_fire = s1_valid && !s1_kill && s2_ready && s1_ld_flow
1128  val s2_ld_valid_dup = RegInit(0.U(6.W))
1129  s2_ld_valid_dup := 0x0.U(6.W)
1130  when (s1_ld_left_fire && !s1_out.isHWPrefetch && s1_ld_flow) { s2_ld_valid_dup := 0x3f.U(6.W) }
1131  when (s1_kill || s1_out.isHWPrefetch || !s1_ld_flow) { s2_ld_valid_dup := 0x0.U(6.W) }
1132  assert(RegNext((s2_valid === s2_ld_valid_dup(0)) || RegNext(s1_out.isHWPrefetch) || RegNext(!s1_ld_flow)))
1133
1134  // Pipeline
1135  // --------------------------------------------------------------------------------
1136  // stage 3
1137  // --------------------------------------------------------------------------------
1138  // writeback and update load queue
1139  val s3_valid        = RegNext(s2_valid && !s2_out.isHWPrefetch && !s2_out.uop.robIdx.needFlush(io.redirect))
1140  val s3_in           = RegEnable(s2_out, s2_fire)
1141  val s3_out          = Wire(Valid(new MemExuOutput))
1142  val s3_dcache_rep   = RegEnable(s2_dcache_fast_rep && s2_troublem, false.B, s2_fire)
1143  val s3_ld_valid_dup = RegEnable(s2_ld_valid_dup, s2_fire)
1144  val s3_fast_rep     = Wire(Bool())
1145  val s3_ld_flow      = RegNext(s2_ld_flow)
1146  val s3_troublem     = RegNext(s2_troublem)
1147  val s3_kill         = s3_in.uop.robIdx.needFlush(io.redirect)
1148  val s3_isvec        = RegNext(s2_isvec)
1149  s3_ready := !s3_valid || s3_kill || sx_can_go
1150
1151  // forwrad last beat
1152  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)
1153  val s3_fwd_data_valid = RegEnable(s2_fwd_data_valid, false.B, s2_valid)
1154  val s3_fwd_frm_d_chan_valid = (s3_fwd_frm_d_chan && s3_fwd_data_valid) && s3_ld_flow
1155
1156
1157  // s3 load fast replay
1158  io.ldu_io.fast_rep_out.valid := s3_valid &&
1159                                  s3_fast_rep &&
1160                                  !s3_in.uop.robIdx.needFlush(io.redirect) &&
1161                                  s3_ld_flow &&
1162                                  !s3_isvec
1163  io.ldu_io.fast_rep_out.bits := s3_in
1164
1165  io.ldu_io.lsq.ldin.valid := s3_valid &&
1166                              (!s3_fast_rep || !io.ldu_io.fast_rep_out.ready) &&
1167                              !s3_in.feedbacked &&
1168                              !s3_in.lateKill &&
1169                              s3_ld_flow
1170  io.ldu_io.lsq.ldin.bits := s3_in
1171  io.ldu_io.lsq.ldin.bits.miss := s3_in.miss && !s3_fwd_frm_d_chan_valid
1172
1173  /* <------- DANGEROUS: Don't change sequence here ! -------> */
1174  io.ldu_io.lsq.ldin.bits.data_wen_dup := s3_ld_valid_dup.asBools
1175  io.ldu_io.lsq.ldin.bits.replacementUpdated := io.ldu_io.dcache.resp.bits.replacementUpdated
1176  io.ldu_io.lsq.ldin.bits.missDbUpdated := RegNext(s2_fire && s2_in.hasROBEntry && !s2_in.tlbMiss && !s2_in.missDbUpdated)
1177
1178  val s3_dly_ld_err =
1179    if (EnableAccurateLoadError) {
1180      (s3_in.lateKill || io.ldu_io.dcache.resp.bits.error_delayed) && RegNext(io.csrCtrl.cache_error_enable)
1181    } else {
1182      WireInit(false.B)
1183    }
1184  io.ldu_io.s3_dly_ld_err := false.B // s3_dly_ld_err && s3_valid
1185  io.ldu_io.fast_rep_out.bits.delayedLoadError := s3_dly_ld_err
1186  io.ldu_io.lsq.ldin.bits.dcacheRequireReplay  := s3_dcache_rep
1187
1188  val s3_vp_match_fail = RegNext(io.ldu_io.lsq.forward.matchInvalid || io.ldu_io.sbuffer.matchInvalid) && s3_troublem
1189  val s3_ldld_rep_inst =
1190      io.ldu_io.lsq.ldld_nuke_query.resp.valid &&
1191      io.ldu_io.lsq.ldld_nuke_query.resp.bits.rep_frm_fetch &&
1192      RegNext(io.csrCtrl.ldld_vio_check_enable)
1193
1194  val s3_rep_info = WireInit(s3_in.rep_info)
1195  s3_rep_info.dcache_miss   := s3_in.rep_info.dcache_miss && !s3_fwd_frm_d_chan_valid && s3_troublem
1196  val s3_rep_frm_fetch = s3_vp_match_fail
1197  val s3_flushPipe = s3_ldld_rep_inst
1198  val s3_sel_rep_cause = PriorityEncoderOH(s3_rep_info.cause.asUInt)
1199  val s3_force_rep     = s3_sel_rep_cause(LoadReplayCauses.C_TM) &&
1200                         !s3_in.uop.exceptionVec(loadAddrMisaligned) &&
1201                         s3_troublem
1202
1203  val s3_ld_exception = ExceptionNO.selectByFu(s3_in.uop.exceptionVec, LduCfg).asUInt.orR && s3_ld_flow
1204  val s3_st_exception = ExceptionNO.selectByFu(s3_in.uop.exceptionVec, StaCfg).asUInt.orR && !s3_ld_flow
1205  val s3_exception    = s3_ld_exception || s3_st_exception
1206  when ((s3_ld_exception || s3_dly_ld_err || s3_rep_frm_fetch) && !s3_force_rep) {
1207    io.ldu_io.lsq.ldin.bits.rep_info.cause := 0.U.asTypeOf(s3_rep_info.cause.cloneType)
1208  } .otherwise {
1209    io.ldu_io.lsq.ldin.bits.rep_info.cause := VecInit(s3_sel_rep_cause.asBools)
1210  }
1211
1212  // Int flow, if hit, will be writebacked at s3
1213  s3_out.valid                := s3_valid &&
1214                                (!s3_ld_flow && !s3_in.feedbacked || !io.ldu_io.lsq.ldin.bits.rep_info.need_rep) && !s3_in.mmio
1215  s3_out.bits.uop             := s3_in.uop
1216  s3_out.bits.uop.exceptionVec(loadAccessFault) := (s3_dly_ld_err  || s3_in.uop.exceptionVec(loadAccessFault)) && s3_ld_flow
1217  s3_out.bits.uop.replayInst := s3_rep_frm_fetch
1218  s3_out.bits.data            := s3_in.data
1219  s3_out.bits.debug.isMMIO    := s3_in.mmio
1220  s3_out.bits.debug.isPerfCnt := false.B
1221  s3_out.bits.debug.paddr     := s3_in.paddr
1222  s3_out.bits.debug.vaddr     := s3_in.vaddr
1223
1224  when (s3_force_rep) {
1225    s3_out.bits.uop.exceptionVec := 0.U.asTypeOf(s3_in.uop.exceptionVec.cloneType)
1226  }
1227
1228  io.ldu_io.rollback.valid := s3_valid && (s3_rep_frm_fetch || s3_flushPipe) && !s3_exception && s3_ld_flow
1229  io.ldu_io.rollback.bits             := DontCare
1230  io.ldu_io.rollback.bits.isRVC       := s3_out.bits.uop.preDecodeInfo.isRVC
1231  io.ldu_io.rollback.bits.robIdx      := s3_out.bits.uop.robIdx
1232  io.ldu_io.rollback.bits.ftqIdx      := s3_out.bits.uop.ftqPtr
1233  io.ldu_io.rollback.bits.ftqOffset   := s3_out.bits.uop.ftqOffset
1234  io.ldu_io.rollback.bits.level       := Mux(s3_rep_frm_fetch, RedirectLevel.flush, RedirectLevel.flushAfter)
1235  io.ldu_io.rollback.bits.cfiUpdate.target := s3_out.bits.uop.pc
1236  io.ldu_io.rollback.bits.debug_runahead_checkpoint_id := s3_out.bits.uop.debugInfo.runahead_checkpoint_id
1237  /* <------- DANGEROUS: Don't change sequence here ! -------> */
1238  io.ldu_io.lsq.ldin.bits.uop := s3_out.bits.uop
1239
1240  val s3_revoke = s3_exception || io.ldu_io.lsq.ldin.bits.rep_info.need_rep
1241  io.ldu_io.lsq.ldld_nuke_query.revoke := s3_revoke
1242  io.ldu_io.lsq.stld_nuke_query.revoke := s3_revoke
1243
1244  // feedback slow
1245  s3_fast_rep := RegNext(s2_fast_rep) &&
1246                 !s3_in.feedbacked &&
1247                 !s3_in.lateKill &&
1248                 !s3_rep_frm_fetch &&
1249                 !s3_exception
1250
1251  val s3_fb_no_waiting = !s3_in.isLoadReplay && !(s3_fast_rep && io.ldu_io.fast_rep_out.ready) && !s3_in.feedbacked
1252
1253  //
1254  io.feedback_slow.valid                 := s3_valid && !s3_in.uop.robIdx.needFlush(io.redirect) && s3_fb_no_waiting && s3_ld_flow
1255  io.feedback_slow.bits.hit              := !io.ldu_io.lsq.ldin.bits.rep_info.need_rep || io.ldu_io.lsq.ldin.ready
1256  io.feedback_slow.bits.flushState       := s3_in.ptwBack
1257  io.feedback_slow.bits.robIdx           := s3_in.uop.robIdx
1258  io.feedback_slow.bits.sourceType       := RSFeedbackType.lrqFull
1259  io.feedback_slow.bits.dataInvalidSqIdx := DontCare
1260
1261  io.vec_stu_io.feedbackSlow.valid := RegNext(s2_vec_feedback.valid && !s2_out.uop.robIdx.needFlush(io.redirect))
1262  io.vec_stu_io.feedbackSlow.bits := RegNext(s2_vec_feedback.bits)
1263
1264  io.ldu_io.ldCancel.ld2Cancel := s3_valid && s3_ld_flow && (                          // is load
1265    io.ldu_io.lsq.ldin.bits.rep_info.need_rep || s3_in.mmio                            // exe fail or is mmio
1266  )
1267
1268  // data from dcache hit
1269  val s3_ld_raw_data_frm_cache = Wire(new LoadDataFromDcacheBundle)
1270  s3_ld_raw_data_frm_cache.respDcacheData       := io.ldu_io.dcache.resp.bits.data_delayed
1271  s3_ld_raw_data_frm_cache.forwardMask          := RegEnable(s2_fwd_mask, s2_valid)
1272  s3_ld_raw_data_frm_cache.forwardData          := RegEnable(s2_fwd_data, s2_valid)
1273  s3_ld_raw_data_frm_cache.uop                  := RegEnable(s2_out.uop, s2_valid)
1274  s3_ld_raw_data_frm_cache.addrOffset           := RegEnable(s2_out.paddr(3, 0), s2_valid)
1275  s3_ld_raw_data_frm_cache.forward_D            := RegEnable(s2_fwd_frm_d_chan, false.B, s2_valid) || s3_fwd_frm_d_chan_valid
1276  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))
1277  s3_ld_raw_data_frm_cache.forward_mshr         := RegEnable(s2_fwd_frm_mshr, false.B, s2_valid)
1278  s3_ld_raw_data_frm_cache.forwardData_mshr     := RegEnable(s2_fwd_data_frm_mshr, s2_valid)
1279  s3_ld_raw_data_frm_cache.forward_result_valid := RegEnable(s2_fwd_data_valid, false.B, s2_valid)
1280
1281  val s3_merged_data_frm_cache = s3_ld_raw_data_frm_cache.mergedData()
1282  val s3_picked_data_frm_cache = LookupTree(s3_ld_raw_data_frm_cache.addrOffset, List(
1283    "b0000".U -> s3_merged_data_frm_cache(63,    0),
1284    "b0001".U -> s3_merged_data_frm_cache(63,    8),
1285    "b0010".U -> s3_merged_data_frm_cache(63,   16),
1286    "b0011".U -> s3_merged_data_frm_cache(63,   24),
1287    "b0100".U -> s3_merged_data_frm_cache(63,   32),
1288    "b0101".U -> s3_merged_data_frm_cache(63,   40),
1289    "b0110".U -> s3_merged_data_frm_cache(63,   48),
1290    "b0111".U -> s3_merged_data_frm_cache(63,   56),
1291    "b1000".U -> s3_merged_data_frm_cache(127,  64),
1292    "b1001".U -> s3_merged_data_frm_cache(127,  72),
1293    "b1010".U -> s3_merged_data_frm_cache(127,  80),
1294    "b1011".U -> s3_merged_data_frm_cache(127,  88),
1295    "b1100".U -> s3_merged_data_frm_cache(127,  96),
1296    "b1101".U -> s3_merged_data_frm_cache(127, 104),
1297    "b1110".U -> s3_merged_data_frm_cache(127, 112),
1298    "b1111".U -> s3_merged_data_frm_cache(127, 120)
1299  ))
1300  val s3_ld_data_frm_cache = rdataHelper(s3_ld_raw_data_frm_cache.uop, s3_picked_data_frm_cache)
1301
1302  // FIXME: add 1 cycle delay ?
1303  io.ldout.bits      := s3_out.bits
1304  io.ldout.bits.data := s3_ld_data_frm_cache
1305  io.ldout.valid     := s3_out.valid && !s3_out.bits.uop.robIdx.needFlush(io.redirect) && s3_ld_flow && !s3_isvec
1306
1307  // for uncache
1308  io.ldu_io.lsq.uncache.ready := true.B
1309
1310  // fast load to load forward
1311  if (EnableLoadToLoadForward) {
1312    io.ldu_io.l2l_fwd_out.valid      := s3_out.valid && !s3_in.lateKill && s3_ld_flow
1313    io.ldu_io.l2l_fwd_out.data       := s3_ld_data_frm_cache
1314    io.ldu_io.l2l_fwd_out.dly_ld_err := s3_dly_ld_err // ecc delayed error
1315  } else {
1316    io.ldu_io.l2l_fwd_out.valid      := false.B
1317    io.ldu_io.l2l_fwd_out.data       := DontCare
1318    io.ldu_io.l2l_fwd_out.dly_ld_err := DontCare
1319  }
1320
1321  // hybrid unit writeback to rob
1322  // delay params
1323  val SelectGroupSize   = RollbackGroupSize
1324  val lgSelectGroupSize = log2Ceil(SelectGroupSize)
1325  val TotalSelectCycles = scala.math.ceil(log2Ceil(LoadQueueRAWSize).toFloat / lgSelectGroupSize).toInt + 1
1326  val TotalDelayCycles  = TotalSelectCycles - 2
1327
1328  // writeback
1329  val sx_valid = Wire(Vec(TotalDelayCycles + 1, Bool()))
1330  val sx_ready = Wire(Vec(TotalDelayCycles + 1, Bool()))
1331  val sx_in    = Wire(Vec(TotalDelayCycles + 1, new MemExuOutput))
1332
1333  sx_can_go := sx_ready.head
1334  for (i <- 0 until TotalDelayCycles + 1) {
1335    if (i == 0) {
1336      sx_valid(i) := s3_valid &&
1337                    !s3_ld_flow &&
1338                    !s3_in.feedbacked &&
1339                    !s3_in.mmio
1340      sx_in(i)    := s3_out.bits
1341      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))
1342    } else {
1343      val cur_kill   = sx_in(i).uop.robIdx.needFlush(io.redirect)
1344      val cur_can_go = (if (i == TotalDelayCycles) io.stout.ready else sx_ready(i+1))
1345      val cur_fire   = sx_valid(i) && !cur_kill && cur_can_go
1346      val prev_fire  = sx_valid(i-1) && !sx_in(i-1).uop.robIdx.needFlush(io.redirect) && sx_ready(i)
1347
1348      sx_ready(i) := !sx_valid(i) || cur_kill || (if (i == TotalDelayCycles) io.stout.ready else sx_ready(i+1))
1349      val sx_valid_can_go = prev_fire || cur_fire || cur_kill
1350      sx_valid(i) := RegEnable(Mux(prev_fire, true.B, false.B), sx_valid_can_go)
1351      sx_in(i) := RegEnable(sx_in(i-1), prev_fire)
1352    }
1353  }
1354
1355  val sx_last_valid = sx_valid.takeRight(1).head
1356  val sx_last_ready = sx_ready.takeRight(1).head
1357  val sx_last_in    = sx_in.takeRight(1).head
1358
1359  sx_last_ready  := !sx_last_valid || sx_last_in.uop.robIdx.needFlush(io.redirect) || io.stout.ready
1360  io.stout.valid := sx_last_valid && !sx_last_in.uop.robIdx.needFlush(io.redirect) && FuType.isStore(sx_last_in.uop.fuType)
1361  io.stout.bits  := sx_last_in
1362
1363   // trigger
1364  val ld_trigger = FuType.isLoad(io.ldout.bits.uop.fuType)
1365  val last_valid_data = RegEnable(io.ldout.bits.data, io.stout.fire)
1366  val hit_ld_addr_trig_hit_vec = Wire(Vec(TriggerNum, Bool()))
1367  val lq_ld_addr_trig_hit_vec = RegNext(io.ldu_io.lsq.trigger.lqLoadAddrTriggerHitVec)
1368  (0 until TriggerNum).map{i => {
1369    val tdata2    = RegNext(RegNext(io.ldu_io.trigger(i).tdata2))
1370    val matchType = RegNext(RegNext(io.ldu_io.trigger(i).matchType))
1371    val tEnable   = RegNext(RegNext(io.ldu_io.trigger(i).tEnable))
1372
1373    hit_ld_addr_trig_hit_vec(i)        := TriggerCmp(RegNext(s3_in.vaddr), tdata2, matchType, tEnable)
1374    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))
1375  }}
1376  io.ldu_io.lsq.trigger.hitLoadAddrTriggerHitVec := hit_ld_addr_trig_hit_vec
1377
1378  // FIXME: please move this part to LoadQueueReplay
1379  io.ldu_io.debug_ls := DontCare
1380  io.stu_io.debug_ls := DontCare
1381  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
1382  io.stu_io.debug_ls.s1_robIdx := s1_in.uop.robIdx.value
1383
1384 // Topdown
1385  io.ldu_io.lsTopdownInfo.s1.robIdx          := s1_in.uop.robIdx.value
1386  io.ldu_io.lsTopdownInfo.s1.vaddr_valid     := s1_valid && s1_in.hasROBEntry
1387  io.ldu_io.lsTopdownInfo.s1.vaddr_bits      := s1_vaddr
1388  io.ldu_io.lsTopdownInfo.s2.robIdx          := s2_in.uop.robIdx.value
1389  io.ldu_io.lsTopdownInfo.s2.paddr_valid     := s2_fire && s2_in.hasROBEntry && !s2_in.tlbMiss
1390  io.ldu_io.lsTopdownInfo.s2.paddr_bits      := s2_in.paddr
1391  io.ldu_io.lsTopdownInfo.s2.first_real_miss := io.ldu_io.dcache.resp.bits.real_miss
1392  io.ldu_io.lsTopdownInfo.s2.cache_miss_en   := s2_fire && s2_in.hasROBEntry && !s2_in.tlbMiss && !s2_in.missDbUpdated
1393
1394  // perf cnt
1395  XSPerfAccumulate("s0_in_valid",                  io.lsin.valid)
1396  XSPerfAccumulate("s0_in_block",                  io.lsin.valid && !io.lsin.fire)
1397  XSPerfAccumulate("s0_in_fire_first_issue",       s0_valid && s0_isFirstIssue)
1398  XSPerfAccumulate("s0_lsq_fire_first_issue",      io.ldu_io.replay.fire)
1399  XSPerfAccumulate("s0_ldu_fire_first_issue",      io.lsin.fire && s0_isFirstIssue)
1400  XSPerfAccumulate("s0_fast_replay_issue",         io.ldu_io.fast_rep_in.fire)
1401  XSPerfAccumulate("s0_stall_out",                 s0_valid && !s0_can_go)
1402  XSPerfAccumulate("s0_stall_ld_dcache",           s0_valid && !io.ldu_io.dcache.req.ready)
1403  XSPerfAccumulate("s0_stall_st_dcache",           s0_valid && !io.stu_io.dcache.req.ready)
1404  XSPerfAccumulate("s0_addr_spec_success",         s0_fire && s0_vaddr(VAddrBits-1, 12) === io.lsin.bits.src(0)(VAddrBits-1, 12))
1405  XSPerfAccumulate("s0_addr_spec_failed",          s0_fire && s0_vaddr(VAddrBits-1, 12) =/= io.lsin.bits.src(0)(VAddrBits-1, 12))
1406  XSPerfAccumulate("s0_addr_spec_success_once",    s0_fire && s0_vaddr(VAddrBits-1, 12) === io.lsin.bits.src(0)(VAddrBits-1, 12) && s0_isFirstIssue)
1407  XSPerfAccumulate("s0_addr_spec_failed_once",     s0_fire && s0_vaddr(VAddrBits-1, 12) =/= io.lsin.bits.src(0)(VAddrBits-1, 12) && s0_isFirstIssue)
1408  XSPerfAccumulate("s0_forward_tl_d_channel",      s0_out.forward_tlDchannel)
1409  XSPerfAccumulate("s0_hardware_prefetch_fire",    s0_fire && s0_hw_prf_select)
1410  XSPerfAccumulate("s0_software_prefetch_fire",    s0_fire && s0_prf && s0_int_iss_select)
1411  XSPerfAccumulate("s0_hardware_prefetch_blocked", io.ldu_io.prefetch_req.valid && !s0_hw_prf_select)
1412  XSPerfAccumulate("s0_hardware_prefetch_total",   io.ldu_io.prefetch_req.valid)
1413
1414  XSPerfAccumulate("s1_in_valid",                  s1_valid)
1415  XSPerfAccumulate("s1_in_fire",                   s1_fire)
1416  XSPerfAccumulate("s1_in_fire_first_issue",       s1_fire && s1_in.isFirstIssue)
1417  XSPerfAccumulate("s1_tlb_miss",                  s1_fire && s1_tlb_miss)
1418  XSPerfAccumulate("s1_tlb_miss_first_issue",      s1_fire && s1_tlb_miss && s1_in.isFirstIssue)
1419  XSPerfAccumulate("s1_stall_out",                 s1_valid && !s1_can_go)
1420  XSPerfAccumulate("s1_late_kill",                 s1_valid && s1_fast_rep_kill)
1421
1422  XSPerfAccumulate("s2_in_valid",                  s2_valid)
1423  XSPerfAccumulate("s2_in_fire",                   s2_fire)
1424  XSPerfAccumulate("s2_in_fire_first_issue",       s2_fire && s2_in.isFirstIssue)
1425  XSPerfAccumulate("s2_dcache_miss",               s2_fire && io.ldu_io.dcache.resp.bits.miss)
1426  XSPerfAccumulate("s2_dcache_miss_first_issue",   s2_fire && io.ldu_io.dcache.resp.bits.miss && s2_in.isFirstIssue)
1427  XSPerfAccumulate("s2_dcache_real_miss_first_issue",   s2_fire && io.ldu_io.dcache.resp.bits.miss && s2_in.isFirstIssue)
1428  XSPerfAccumulate("s2_full_forward",              s2_fire && s2_full_fwd)
1429  XSPerfAccumulate("s2_dcache_miss_full_forward",  s2_fire && s2_dcache_miss)
1430  XSPerfAccumulate("s2_fwd_frm_d_can",             s2_valid && s2_fwd_frm_d_chan)
1431  XSPerfAccumulate("s2_fwd_frm_d_chan_or_mshr",    s2_valid && s2_fwd_frm_d_chan_or_mshr)
1432  XSPerfAccumulate("s2_stall_out",                 s2_fire && !s2_can_go)
1433  XSPerfAccumulate("s2_prefetch",                  s2_fire && s2_prf)
1434  XSPerfAccumulate("s2_prefetch_ignored",          s2_fire && s2_prf && io.ldu_io.dcache.s2_mq_nack) // ignore prefetch for mshr full / miss req port conflict
1435  XSPerfAccumulate("s2_prefetch_miss",             s2_fire && s2_prf && io.ldu_io.dcache.resp.bits.miss) // prefetch req miss in l1
1436  XSPerfAccumulate("s2_prefetch_hit",              s2_fire && s2_prf && !io.ldu_io.dcache.resp.bits.miss) // prefetch req hit in l1
1437  XSPerfAccumulate("s2_prefetch_accept",           s2_fire && s2_prf && io.ldu_io.dcache.resp.bits.miss && !io.ldu_io.dcache.s2_mq_nack) // prefetch a missed line in l1, and l1 accepted it
1438  XSPerfAccumulate("s2_forward_req",               s2_fire && s2_in.forward_tlDchannel)
1439  XSPerfAccumulate("s2_successfully_forward_channel_D", s2_fire && s2_fwd_frm_d_chan && s2_fwd_data_valid)
1440  XSPerfAccumulate("s2_successfully_forward_mshr",      s2_fire && s2_fwd_frm_mshr && s2_fwd_data_valid)
1441
1442  XSPerfAccumulate("s3_fwd_frm_d_chan",            s3_valid && s3_fwd_frm_d_chan_valid)
1443
1444  XSPerfAccumulate("load_to_load_forward",                      s1_try_ptr_chasing && !s1_ptr_chasing_canceled)
1445  XSPerfAccumulate("load_to_load_forward_try",                  s1_try_ptr_chasing)
1446  XSPerfAccumulate("load_to_load_forward_fail",                 s1_cancel_ptr_chasing)
1447  XSPerfAccumulate("load_to_load_forward_fail_cancelled",       s1_cancel_ptr_chasing && s1_ptr_chasing_canceled)
1448  XSPerfAccumulate("load_to_load_forward_fail_wakeup_mismatch", s1_cancel_ptr_chasing && !s1_ptr_chasing_canceled && s1_not_fast_match)
1449  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)
1450  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)
1451  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)
1452
1453  // bug lyq: some signals in perfEvents are no longer suitable for the current MemBlock design
1454  // hardware performance counter
1455  val perfEvents = Seq(
1456    ("load_s0_in_fire         ", s0_fire                                                        ),
1457    ("load_to_load_forward    ", s1_fire && s1_try_ptr_chasing && !s1_ptr_chasing_canceled      ),
1458    ("stall_dcache            ", s0_valid && s0_can_go && !io.ldu_io.dcache.req.ready           ),
1459    ("load_s1_in_fire         ", s0_fire                                                        ),
1460    ("load_s1_tlb_miss        ", s1_fire && io.tlb.resp.bits.miss                               ),
1461    ("load_s2_in_fire         ", s1_fire                                                        ),
1462    ("load_s2_dcache_miss     ", s2_fire && io.ldu_io.dcache.resp.bits.miss                     ),
1463  )
1464  generatePerfEvent()
1465}