xref: /XiangShan/src/main/scala/xiangshan/mem/pipeline/HybridUnit.scala (revision 43965d0268e52c5034de928e30619c5fae33cefd)
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.cache._
33import xiangshan.cache.wpu.ReplayCarry
34import xiangshan.cache.mmu.{TlbCmd, TlbReq, TlbRequestIO, TlbResp}
35import xiangshan.mem.mdp._
36
37class HybridUnit(implicit p: Parameters) extends XSModule
38  with HasLoadHelper
39  with HasPerfEvents
40  with HasDCacheParameters
41  with HasCircularQueuePtrHelper
42{
43  val io = IO(new Bundle() {
44    // control
45    val redirect      = Flipped(ValidIO(new Redirect))
46    val csrCtrl       = Flipped(new CustomCSRCtrlIO)
47
48    // flow in
49    val lsin          = Flipped(Decoupled(new MemExuInput))
50
51    // flow out
52    val ldout = DecoupledIO(new MemExuOutput)
53    val stout = DecoupledIO(new MemExuOutput)
54
55    val ldu_io = new Bundle() {
56      // dcache
57      val dcache        = new DCacheLoadIO
58
59      // data path
60      val sbuffer       = new LoadForwardQueryIO
61      val lsq           = new LoadToLsqIO
62      val tl_d_channel  = Input(new DcacheToLduForwardIO)
63      val forward_mshr  = Flipped(new LduToMissqueueForwardIO)
64      val refill        = Flipped(ValidIO(new Refill))
65      val l2_hint       = Input(Valid(new L2ToL1Hint))
66
67      // fast wakeup
68      val fast_uop = ValidIO(new DynInst) // early wakeup signal generated in load_s1, send to RS in load_s2
69
70      // trigger
71      val trigger = Vec(3, new LoadUnitTriggerIO)
72
73      // load to load fast path
74      val l2l_fwd_in    = Input(new LoadToLoadIO)
75      val l2l_fwd_out   = Output(new LoadToLoadIO)
76
77      val ld_fast_match    = Input(Bool())
78      val ld_fast_fuOpType = Input(UInt())
79      val ld_fast_imm      = Input(UInt(12.W))
80
81      // hardware prefetch to l1 cache req
82      val prefetch_req    = Flipped(ValidIO(new L1PrefetchReq))
83
84      // iq cancel
85      val ldCancel = Output(new LoadCancelIO()) // use to cancel the uops waked by this load, and cancel load
86
87      // load ecc error
88      val s3_dly_ld_err = Output(Bool()) // Note that io.s3_dly_ld_err and io.lsq.s3_dly_ld_err is different
89
90      // schedule error query
91      val stld_nuke_query = Flipped(Vec(StorePipelineWidth, Valid(new StoreNukeQueryIO)))
92
93      // queue-based replay
94      val replay       = Flipped(Decoupled(new LsPipelineBundle))
95      val lq_rep_full  = Input(Bool())
96
97      // misc
98      val s2_ptr_chasing = Output(Bool()) // provide right pc for hw prefetch
99
100      // Load fast replay path
101      val fast_rep_in  = Flipped(Decoupled(new LqWriteBundle))
102      val fast_rep_out = Decoupled(new LqWriteBundle)
103
104      // perf
105      val debug_ls         = Output(new DebugLsInfoBundle)
106      val lsTopdownInfo    = Output(new LsTopdownInfo)
107    }
108
109    val stu_io = new Bundle() {
110      val dcache          = new DCacheStoreIO
111      val prefetch_req    = Flipped(DecoupledIO(new StorePrefetchReq))
112      val issue           = Valid(new MemExuInput)
113      val lsq             = ValidIO(new LsPipelineBundle)
114      val lsq_replenish   = Output(new LsPipelineBundle())
115      val stld_nuke_query = Valid(new StoreNukeQueryIO)
116      val st_mask_out     = Valid(new StoreMaskBundle)
117      val debug_ls        = Output(new DebugLsInfoBundle)
118    }
119
120    // prefetch
121    val prefetch_train            = ValidIO(new LdPrefetchTrainBundle()) // provide prefetch info to sms
122    val prefetch_train_l1         = ValidIO(new LdPrefetchTrainBundle()) // provide prefetch info to stream & stride
123    val canAcceptLowConfPrefetch  = Output(Bool())
124    val canAcceptHighConfPrefetch = Output(Bool())
125    val correctMissTrain          = Input(Bool())
126
127    // data path
128    val tlb           = new TlbRequestIO(2)
129    val pmp           = Flipped(new PMPRespBundle()) // arrive same to tlb now
130
131
132    // rs feedback
133    val feedback_fast = ValidIO(new RSFeedback) // stage 2
134    val feedback_slow = ValidIO(new RSFeedback) // stage 3
135  })
136
137  val StorePrefetchL1Enabled = EnableStorePrefetchAtCommit || EnableStorePrefetchAtIssue || EnableStorePrefetchSPB
138  val s1_ready, s2_ready, s3_ready, sx_can_go = WireInit(false.B)
139
140  // Pipeline
141  // --------------------------------------------------------------------------------
142  // stage 0
143  // --------------------------------------------------------------------------------
144  // generate addr, use addr to query DCache and DTLB
145  val s0_valid         = Wire(Bool())
146  val s0_dcache_ready  = Wire(Bool())
147  val s0_kill          = Wire(Bool())
148  val s0_vaddr         = Wire(UInt(VAddrBits.W))
149  val s0_mask          = Wire(UInt((VLEN/8).W))
150  val s0_uop           = Wire(new DynInst)
151  val s0_has_rob_entry = Wire(Bool())
152  val s0_rsIdx         = Wire(UInt(log2Up(MemIQSizeMax).W))
153  val s0_mshrid        = Wire(UInt())
154  val s0_try_l2l       = Wire(Bool())
155  val s0_rep_carry     = Wire(new ReplayCarry(nWays))
156  val s0_isFirstIssue  = Wire(Bool())
157  val s0_fast_rep      = Wire(Bool())
158  val s0_ld_rep        = Wire(Bool())
159  val s0_l2l_fwd       = Wire(Bool())
160  val s0_sched_idx     = Wire(UInt())
161  val s0_deqPortIdx    = Wire(UInt(log2Ceil(LoadPipelineWidth).W))
162  val s0_can_go        = s1_ready
163  val s0_fire          = s0_valid && s0_dcache_ready && s0_can_go
164  val s0_out           = Wire(new LqWriteBundle)
165
166  // load flow select/gen
167  // src0: super load replayed by LSQ (cache miss replay) (io.ldu_io.replay)
168  // src1: fast load replay (io.ldu_io.fast_rep_in)
169  // src2: load replayed by LSQ (io.ldu_io.replay)
170  // src3: hardware prefetch from prefetchor (high confidence) (io.prefetch)
171  // src4: int read / software prefetch first issue from RS (io.in)
172  // src5: vec read first issue from RS (TODO)
173  // src6: load try pointchaising when no issued or replayed load (io.fastpath)
174  // src7: hardware prefetch from prefetchor (high confidence) (io.prefetch)
175  // priority: high to low
176  val s0_ld_flow             = FuType.isLoad(s0_uop.fuType)
177  val s0_rep_stall           = io.lsin.valid && isAfter(io.ldu_io.replay.bits.uop.robIdx, io.lsin.bits.uop.robIdx)
178  val s0_super_ld_rep_valid  = io.ldu_io.replay.valid && io.ldu_io.replay.bits.forward_tlDchannel
179  val s0_ld_fast_rep_valid   = io.ldu_io.fast_rep_in.valid
180  val s0_ld_rep_valid        = io.ldu_io.replay.valid && !io.ldu_io.replay.bits.forward_tlDchannel && !s0_rep_stall
181  val s0_high_conf_prf_valid = io.ldu_io.prefetch_req.valid && io.ldu_io.prefetch_req.bits.confidence > 0.U
182  val s0_int_iss_valid       = io.lsin.valid // int flow first issue or software prefetch
183  val s0_vec_iss_valid       = WireInit(false.B) // TODO
184  val s0_l2l_fwd_valid       = io.ldu_io.l2l_fwd_in.valid && io.ldu_io.ld_fast_match
185  val s0_low_conf_prf_valid  = io.ldu_io.prefetch_req.valid && io.ldu_io.prefetch_req.bits.confidence === 0.U
186  dontTouch(s0_super_ld_rep_valid)
187  dontTouch(s0_ld_fast_rep_valid)
188  dontTouch(s0_ld_rep_valid)
189  dontTouch(s0_high_conf_prf_valid)
190  dontTouch(s0_int_iss_valid)
191  dontTouch(s0_vec_iss_valid)
192  dontTouch(s0_l2l_fwd_valid)
193  dontTouch(s0_low_conf_prf_valid)
194
195  // load flow source ready
196  val s0_super_ld_rep_ready  = WireInit(true.B)
197  val s0_ld_fast_rep_ready   = !s0_super_ld_rep_valid
198  val s0_ld_rep_ready        = !s0_super_ld_rep_valid &&
199                               !s0_ld_fast_rep_valid
200  val s0_high_conf_prf_ready = !s0_super_ld_rep_valid &&
201                               !s0_ld_fast_rep_valid &&
202                               !s0_ld_rep_valid
203
204  val s0_int_iss_ready       = !s0_super_ld_rep_valid &&
205                               !s0_ld_fast_rep_valid &&
206                               !s0_ld_rep_valid &&
207                               !s0_high_conf_prf_valid
208
209  val s0_vec_iss_ready       = !s0_super_ld_rep_valid &&
210                               !s0_ld_fast_rep_valid &&
211                               !s0_ld_rep_valid &&
212                               !s0_high_conf_prf_valid &&
213                               !s0_int_iss_valid
214
215  val s0_l2l_fwd_ready       = !s0_super_ld_rep_valid &&
216                               !s0_ld_fast_rep_valid &&
217                               !s0_ld_rep_valid &&
218                               !s0_high_conf_prf_valid &&
219                               !s0_int_iss_valid &&
220                               !s0_vec_iss_valid
221
222  val s0_low_conf_prf_ready  = !s0_super_ld_rep_valid &&
223                               !s0_ld_fast_rep_valid &&
224                               !s0_ld_rep_valid &&
225                               !s0_high_conf_prf_valid &&
226                               !s0_int_iss_valid &&
227                               !s0_vec_iss_valid &&
228                               !s0_l2l_fwd_valid
229  dontTouch(s0_super_ld_rep_ready)
230  dontTouch(s0_ld_fast_rep_ready)
231  dontTouch(s0_ld_rep_ready)
232  dontTouch(s0_high_conf_prf_ready)
233  dontTouch(s0_int_iss_ready)
234  dontTouch(s0_vec_iss_ready)
235  dontTouch(s0_l2l_fwd_ready)
236  dontTouch(s0_low_conf_prf_ready)
237
238  // load flow source select (OH)
239  val s0_super_ld_rep_select = s0_super_ld_rep_valid && s0_super_ld_rep_ready
240  val s0_ld_fast_rep_select  = s0_ld_fast_rep_valid && s0_ld_fast_rep_ready
241  val s0_ld_rep_select       = s0_ld_rep_valid && s0_ld_rep_ready
242  val s0_hw_prf_select       = s0_high_conf_prf_ready && s0_high_conf_prf_valid ||
243                               s0_low_conf_prf_ready && s0_low_conf_prf_valid
244  val s0_int_iss_select      = s0_int_iss_ready && s0_int_iss_valid
245  val s0_vec_iss_select      = s0_vec_iss_ready && s0_vec_iss_valid
246  val s0_l2l_fwd_select      = s0_l2l_fwd_ready && s0_l2l_fwd_valid
247  assert(!s0_vec_iss_select) // to be added
248  dontTouch(s0_super_ld_rep_select)
249  dontTouch(s0_ld_fast_rep_select)
250  dontTouch(s0_ld_rep_select)
251  dontTouch(s0_hw_prf_select)
252  dontTouch(s0_int_iss_select)
253  dontTouch(s0_vec_iss_select)
254  dontTouch(s0_l2l_fwd_select)
255
256  s0_valid := (s0_super_ld_rep_valid ||
257               s0_ld_fast_rep_valid ||
258               s0_ld_rep_valid ||
259               s0_high_conf_prf_valid ||
260               s0_int_iss_valid ||
261               s0_vec_iss_valid ||
262               s0_l2l_fwd_valid ||
263               s0_low_conf_prf_valid) && !s0_kill
264
265  // which is S0's out is ready and dcache is ready
266  val s0_try_ptr_chasing      = s0_l2l_fwd_select
267  val s0_do_try_ptr_chasing   = s0_try_ptr_chasing && s0_can_go && io.ldu_io.dcache.req.ready
268  val s0_ptr_chasing_vaddr    = io.ldu_io.l2l_fwd_in.data(5, 0) +& io.ldu_io.ld_fast_imm(5, 0)
269  val s0_ptr_chasing_canceled = WireInit(false.B)
270  s0_kill := s0_ptr_chasing_canceled || (s0_out.uop.robIdx.needFlush(io.redirect) && !s0_try_ptr_chasing)
271
272  // prefetch related ctrl signal
273  val s0_prf    = Wire(Bool())
274  val s0_prf_rd = Wire(Bool())
275  val s0_prf_wr = Wire(Bool())
276  val s0_hw_prf = s0_hw_prf_select
277
278  io.canAcceptLowConfPrefetch  := s0_low_conf_prf_ready
279  io.canAcceptHighConfPrefetch := s0_high_conf_prf_ready
280
281  if (StorePrefetchL1Enabled) {
282    s0_dcache_ready := Mux(s0_ld_flow, io.ldu_io.dcache.req.ready, io.stu_io.dcache.req.ready)
283  } else {
284    s0_dcache_ready := Mux(s0_ld_flow, io.ldu_io.dcache.req.ready, true.B)
285  }
286
287  // query DTLB
288  io.tlb.req.valid                   := s0_valid && s0_dcache_ready
289  io.tlb.req.bits.cmd                := Mux(s0_prf,
290                                         Mux(s0_prf_wr, TlbCmd.write, TlbCmd.read),
291                                         Mux(s0_ld_flow, TlbCmd.read, TlbCmd.write)
292                                       )
293  io.tlb.req.bits.vaddr              := Mux(s0_hw_prf_select, io.ldu_io.prefetch_req.bits.paddr, s0_vaddr)
294  io.tlb.req.bits.size               := LSUOpType.size(s0_uop.fuOpType)
295  io.tlb.req.bits.kill               := s0_kill
296  io.tlb.req.bits.memidx.is_ld       := s0_ld_flow
297  io.tlb.req.bits.memidx.is_st       := !s0_ld_flow
298  io.tlb.req.bits.memidx.idx         := s0_uop.lqIdx.value
299  io.tlb.req.bits.debug.robIdx       := s0_uop.robIdx
300  io.tlb.req.bits.no_translate       := s0_hw_prf_select  // hw b.reqetch addr does not need to be translated
301  io.tlb.req.bits.debug.pc           := s0_uop.pc
302  io.tlb.req.bits.debug.isFirstIssue := s0_isFirstIssue
303
304  // query DCache
305  // for load
306  io.ldu_io.dcache.req.valid             := s0_valid && s0_dcache_ready && s0_ld_flow
307  io.ldu_io.dcache.req.bits.cmd          :=  Mux(s0_prf_rd, MemoryOpConstants.M_PFR,
308                                              Mux(s0_prf_wr, MemoryOpConstants.M_PFW, MemoryOpConstants.M_XRD))
309  io.ldu_io.dcache.req.bits.vaddr        := s0_vaddr
310  io.ldu_io.dcache.req.bits.mask         := s0_mask
311  io.ldu_io.dcache.req.bits.data         := DontCare
312  io.ldu_io.dcache.req.bits.isFirstIssue := s0_isFirstIssue
313  io.ldu_io.dcache.req.bits.instrtype    := Mux(s0_prf, DCACHE_PREFETCH_SOURCE.U, LOAD_SOURCE.U)
314  io.ldu_io.dcache.req.bits.debug_robIdx := s0_uop.robIdx.value
315  io.ldu_io.dcache.req.bits.replayCarry  := s0_rep_carry
316  io.ldu_io.dcache.req.bits.id           := DontCare // TODO: update cache meta
317  io.ldu_io.dcache.pf_source             := Mux(s0_hw_prf_select, io.ldu_io.prefetch_req.bits.pf_source.value, L1_HW_PREFETCH_NULL)
318
319  // for store
320  io.stu_io.dcache.req.valid             := s0_valid && s0_dcache_ready && !s0_ld_flow && !s0_prf
321  io.stu_io.dcache.req.bits.cmd          := MemoryOpConstants.M_PFW
322  io.stu_io.dcache.req.bits.vaddr        := s0_vaddr
323  io.stu_io.dcache.req.bits.instrtype    := Mux(s0_prf, DCACHE_PREFETCH_SOURCE.U, STORE_SOURCE.U)
324
325  // load flow priority mux
326  def fromNullSource() = {
327    s0_vaddr         := 0.U
328    s0_mask          := 0.U
329    s0_uop           := 0.U.asTypeOf(new DynInst)
330    s0_try_l2l       := false.B
331    s0_has_rob_entry := false.B
332    s0_rsIdx         := 0.U
333    s0_rep_carry     := 0.U.asTypeOf(s0_rep_carry.cloneType)
334    s0_mshrid        := 0.U
335    s0_isFirstIssue  := false.B
336    s0_fast_rep      := false.B
337    s0_ld_rep        := false.B
338    s0_l2l_fwd       := false.B
339    s0_prf           := false.B
340    s0_prf_rd        := false.B
341    s0_prf_wr        := false.B
342    s0_sched_idx     := 0.U
343    s0_deqPortIdx    := 0.U
344  }
345
346  def fromFastReplaySource(src: LqWriteBundle) = {
347    s0_vaddr         := src.vaddr
348    s0_mask          := src.mask
349    s0_uop           := src.uop
350    s0_try_l2l       := false.B
351    s0_has_rob_entry := src.hasROBEntry
352    s0_rep_carry     := src.rep_info.rep_carry
353    s0_mshrid        := src.rep_info.mshr_id
354    s0_rsIdx         := src.rsIdx
355    s0_isFirstIssue  := false.B
356    s0_fast_rep      := true.B
357    s0_ld_rep        := src.isLoadReplay
358    s0_l2l_fwd       := false.B
359    s0_prf           := LSUOpType.isPrefetch(src.uop.fuOpType)
360    s0_prf_rd        := src.uop.fuOpType === LSUOpType.prefetch_r
361    s0_prf_wr        := src.uop.fuOpType === LSUOpType.prefetch_w
362    s0_sched_idx     := src.schedIndex
363    s0_deqPortIdx    := src.deqPortIdx
364  }
365
366  def fromNormalReplaySource(src: LsPipelineBundle) = {
367    s0_vaddr         := src.vaddr
368    s0_mask          := genVWmask(src.vaddr, src.uop.fuOpType(1, 0))
369    s0_uop           := src.uop
370    s0_try_l2l       := false.B
371    s0_has_rob_entry := true.B
372    s0_rsIdx         := src.rsIdx
373    s0_rep_carry     := src.replayCarry
374    s0_mshrid        := src.mshrid
375    s0_isFirstIssue  := false.B
376    s0_fast_rep      := false.B
377    s0_ld_rep        := true.B
378    s0_l2l_fwd       := false.B
379    s0_prf           := LSUOpType.isPrefetch(src.uop.fuOpType)
380    s0_prf_rd        := src.uop.fuOpType === LSUOpType.prefetch_r
381    s0_prf_wr        := src.uop.fuOpType === LSUOpType.prefetch_w
382    s0_sched_idx     := src.schedIndex
383    s0_deqPortIdx    := src.deqPortIdx
384  }
385
386  def fromPrefetchSource(src: L1PrefetchReq) = {
387    s0_vaddr         := src.getVaddr()
388    s0_mask          := 0.U
389    s0_uop           := DontCare
390    s0_try_l2l       := false.B
391    s0_has_rob_entry := false.B
392    s0_rsIdx         := 0.U
393    s0_rep_carry     := 0.U.asTypeOf(s0_rep_carry.cloneType)
394    s0_mshrid        := 0.U
395    s0_isFirstIssue  := false.B
396    s0_fast_rep      := false.B
397    s0_ld_rep        := false.B
398    s0_l2l_fwd       := false.B
399    s0_prf           := true.B
400    s0_prf_rd        := !src.is_store
401    s0_prf_wr        := src.is_store
402    s0_sched_idx     := 0.U
403    s0_deqPortIdx    := 0.U
404  }
405
406  def fromIntIssueSource(src: MemExuInput) = {
407    s0_vaddr         := src.src(0) + SignExt(src.uop.imm(11, 0), VAddrBits)
408    s0_mask          := genVWmask(s0_vaddr, src.uop.fuOpType(1,0))
409    s0_uop           := src.uop
410    s0_try_l2l       := false.B
411    s0_has_rob_entry := true.B
412    s0_rsIdx         := src.iqIdx
413    s0_rep_carry     := 0.U.asTypeOf(s0_rep_carry.cloneType)
414    s0_mshrid        := 0.U
415    s0_isFirstIssue  := true.B
416    s0_fast_rep      := false.B
417    s0_ld_rep        := false.B
418    s0_l2l_fwd       := false.B
419    s0_prf           := LSUOpType.isPrefetch(src.uop.fuOpType)
420    s0_prf_rd        := src.uop.fuOpType === LSUOpType.prefetch_r
421    s0_prf_wr        := src.uop.fuOpType === LSUOpType.prefetch_w
422    s0_sched_idx     := 0.U
423    s0_deqPortIdx    := src.deqPortIdx
424  }
425
426  def fromVecIssueSource() = {
427    s0_vaddr         := 0.U
428    s0_mask          := 0.U
429    s0_uop           := 0.U.asTypeOf(new DynInst)
430    s0_try_l2l       := false.B
431    s0_has_rob_entry := false.B
432    s0_rsIdx         := 0.U
433    s0_rep_carry     := 0.U.asTypeOf(s0_rep_carry.cloneType)
434    s0_mshrid        := 0.U
435    s0_isFirstIssue  := false.B
436    s0_fast_rep      := false.B
437    s0_ld_rep        := false.B
438    s0_l2l_fwd       := false.B
439    s0_prf           := false.B
440    s0_prf_rd        := false.B
441    s0_prf_wr        := false.B
442    s0_sched_idx     := 0.U
443    s0_deqPortIdx    := 0.U
444  }
445
446  def fromLoadToLoadSource(src: LoadToLoadIO) = {
447    s0_vaddr              := Cat(src.data(XLEN-1, 6), s0_ptr_chasing_vaddr(5,0))
448    s0_mask               := genVWmask(s0_vaddr, io.ldu_io.ld_fast_fuOpType(1, 0))
449    // When there's no valid instruction from RS and LSQ, we try the load-to-load forwarding.
450    // Assume the pointer chasing is always ld.
451    s0_uop.fuOpType  := io.ldu_io.ld_fast_fuOpType
452    s0_try_l2l            := true.B
453    // we dont care s0_isFirstIssue and s0_rsIdx and s0_sqIdx and s0_deqPortIdx in S0 when trying pointchasing
454    // because these signals will be updated in S1
455    s0_has_rob_entry      := false.B
456    s0_rsIdx              := 0.U
457    s0_mshrid             := 0.U
458    s0_rep_carry          := 0.U.asTypeOf(s0_rep_carry.cloneType)
459    s0_isFirstIssue       := true.B
460    s0_fast_rep           := false.B
461    s0_ld_rep             := false.B
462    s0_l2l_fwd            := true.B
463    s0_prf                := false.B
464    s0_prf_rd             := false.B
465    s0_prf_wr             := false.B
466    s0_sched_idx          := 0.U
467    s0_deqPortIdx         := 0.U
468  }
469
470  // set default
471  s0_uop := DontCare
472  when (s0_super_ld_rep_select)      { fromNormalReplaySource(io.ldu_io.replay.bits)     }
473  .elsewhen (s0_ld_fast_rep_select)  { fromFastReplaySource(io.ldu_io.fast_rep_in.bits)  }
474  .elsewhen (s0_ld_rep_select)       { fromNormalReplaySource(io.ldu_io.replay.bits)     }
475  .elsewhen (s0_hw_prf_select)       { fromPrefetchSource(io.ldu_io.prefetch_req.bits)   }
476  .elsewhen (s0_int_iss_select)      { fromIntIssueSource(io.lsin.bits)           }
477  .elsewhen (s0_vec_iss_select)      { fromVecIssueSource()                       }
478  .otherwise {
479    if (EnableLoadToLoadForward) {
480      fromLoadToLoadSource(io.ldu_io.l2l_fwd_in)
481    } else {
482      fromNullSource()
483    }
484  }
485
486  // address align check
487  val s0_addr_aligned = LookupTree(s0_uop.fuOpType(1, 0), List(
488    "b00".U   -> true.B,                   //b
489    "b01".U   -> (s0_vaddr(0)    === 0.U), //h
490    "b10".U   -> (s0_vaddr(1, 0) === 0.U), //w
491    "b11".U   -> (s0_vaddr(2, 0) === 0.U)  //d
492  ))
493
494  // accept load flow if dcache ready (tlb is always ready)
495  // TODO: prefetch need writeback to loadQueueFlag
496  s0_out               := DontCare
497  s0_out.rsIdx         := s0_rsIdx
498  s0_out.vaddr         := s0_vaddr
499  s0_out.mask          := s0_mask
500  s0_out.uop           := s0_uop
501  s0_out.isFirstIssue  := s0_isFirstIssue
502  s0_out.hasROBEntry   := s0_has_rob_entry
503  s0_out.isPrefetch    := s0_prf
504  s0_out.isHWPrefetch  := s0_hw_prf
505  s0_out.isFastReplay  := s0_fast_rep
506  s0_out.isLoadReplay  := s0_ld_rep
507  s0_out.isFastPath    := s0_l2l_fwd
508  s0_out.mshrid        := s0_mshrid
509  s0_out.uop.exceptionVec(loadAddrMisaligned)  := !s0_addr_aligned && s0_ld_flow
510  s0_out.uop.exceptionVec(storeAddrMisaligned) := !s0_addr_aligned && !s0_ld_flow
511  s0_out.forward_tlDchannel := s0_super_ld_rep_select
512  when(io.tlb.req.valid && s0_isFirstIssue) {
513    s0_out.uop.debugInfo.tlbFirstReqTime := GTimer()
514  }.otherwise{
515    s0_out.uop.debugInfo.tlbFirstReqTime := s0_uop.debugInfo.tlbFirstReqTime
516  }
517  s0_out.schedIndex     := s0_sched_idx
518  s0_out.deqPortIdx     := s0_deqPortIdx
519
520  // load fast replay
521  io.ldu_io.fast_rep_in.ready := (s0_can_go && io.ldu_io.dcache.req.ready && s0_ld_fast_rep_ready)
522
523  // load flow source ready
524  // cache missed load has highest priority
525  // always accept cache missed load flow from load replay queue
526  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))
527
528  // accept load flow from rs when:
529  // 1) there is no lsq-replayed load
530  // 2) there is no fast replayed load
531  // 3) there is no high confidence prefetch request
532  io.lsin.ready := (s0_can_go &&
533                    Mux(FuType.isLoad(io.lsin.bits.uop.fuType), io.ldu_io.dcache.req.ready,
534                    (if (StorePrefetchL1Enabled) io.stu_io.dcache.req.ready else true.B)) && s0_int_iss_ready)
535
536
537  // for hw prefetch load flow feedback, to be added later
538  // io.prefetch_in.ready := s0_hw_prf_select
539
540  // dcache replacement extra info
541  // TODO: should prefetch load update replacement?
542  io.ldu_io.dcache.replacementUpdated := Mux(s0_ld_rep_select || s0_super_ld_rep_select, io.ldu_io.replay.bits.replacementUpdated, false.B)
543
544  io.stu_io.prefetch_req.ready := s1_ready && io.stu_io.dcache.req.ready && !io.lsin.valid
545
546  io.stu_io.st_mask_out.valid       := s0_valid && !s0_ld_flow
547  io.stu_io.st_mask_out.bits.mask   := s0_out.mask
548  io.stu_io.st_mask_out.bits.sqIdx  := s0_out.uop.sqIdx
549
550  // load debug
551  XSDebug(io.ldu_io.dcache.req.fire && s0_ld_flow,
552    p"[DCACHE LOAD REQ] pc ${Hexadecimal(s0_uop.pc)}, vaddr ${Hexadecimal(s0_vaddr)}\n"
553  )
554  XSDebug(s0_valid && s0_ld_flow,
555    p"S0: pc ${Hexadecimal(s0_out.uop.pc)}, lqIdx ${Hexadecimal(s0_out.uop.lqIdx.asUInt)}, " +
556    p"vaddr ${Hexadecimal(s0_out.vaddr)}, mask ${Hexadecimal(s0_out.mask)}\n")
557
558  // store debug
559  XSDebug(io.stu_io.dcache.req.fire && !s0_ld_flow,
560    p"[DCACHE STORE REQ] pc ${Hexadecimal(s0_uop.pc)}, vaddr ${Hexadecimal(s0_vaddr)}\n"
561  )
562  XSDebug(s0_valid && !s0_ld_flow,
563    p"S0: pc ${Hexadecimal(s0_out.uop.pc)}, sqIdx ${Hexadecimal(s0_out.uop.sqIdx.asUInt)}, " +
564    p"vaddr ${Hexadecimal(s0_out.vaddr)}, mask ${Hexadecimal(s0_out.mask)}\n")
565
566
567  // Pipeline
568  // --------------------------------------------------------------------------------
569  // stage 1
570  // --------------------------------------------------------------------------------
571  // TLB resp (send paddr to dcache)
572  val s1_valid      = RegInit(false.B)
573  val s1_in         = Wire(new LqWriteBundle)
574  val s1_out        = Wire(new LqWriteBundle)
575  val s1_kill       = Wire(Bool())
576  val s1_can_go     = s2_ready
577  val s1_fire       = s1_valid && !s1_kill && s1_can_go
578  val s1_ld_flow    = RegNext(s0_ld_flow)
579
580  s1_ready := !s1_valid || s1_kill || s2_ready
581  when (s0_fire) { s1_valid := true.B }
582  .elsewhen (s1_fire) { s1_valid := false.B }
583  .elsewhen (s1_kill) { s1_valid := false.B }
584  s1_in   := RegEnable(s0_out, s0_fire)
585
586  val s1_fast_rep_dly_err = RegNext(io.ldu_io.fast_rep_in.bits.delayedLoadError)
587  val s1_fast_rep_kill    = s1_fast_rep_dly_err && s1_in.isFastReplay
588  val s1_l2l_fwd_dly_err  = RegNext(io.ldu_io.l2l_fwd_in.dly_ld_err)
589  val s1_l2l_fwd_kill     = s1_l2l_fwd_dly_err && s1_in.isFastPath
590  val s1_late_kill        = s1_fast_rep_kill || s1_l2l_fwd_kill
591  val s1_vaddr_hi         = Wire(UInt())
592  val s1_vaddr_lo         = Wire(UInt())
593  val s1_vaddr            = Wire(UInt())
594  val s1_paddr_dup_lsu    = Wire(UInt())
595  val s1_paddr_dup_dcache = Wire(UInt())
596  val s1_ld_exception     = ExceptionNO.selectByFu(s1_out.uop.exceptionVec, LduCfg).asUInt.orR   // af & pf exception were modified below.
597  val s1_st_exception     = ExceptionNO.selectByFu(s1_out.uop.exceptionVec, StaCfg).asUInt.orR   // af & pf exception were modified below.
598  val s1_exception        = (s1_ld_flow && s1_ld_exception) || (!s1_ld_flow && s1_st_exception)
599  val s1_tlb_miss         = io.tlb.resp.bits.miss
600  val s1_prf              = s1_in.isPrefetch
601  val s1_hw_prf           = s1_in.isHWPrefetch
602  val s1_sw_prf           = s1_prf && !s1_hw_prf
603  val s1_tlb_memidx       = io.tlb.resp.bits.memidx
604
605  // mmio cbo decoder
606  val s1_mmio_cbo  = (s1_in.uop.fuOpType === LSUOpType.cbo_clean ||
607                      s1_in.uop.fuOpType === LSUOpType.cbo_flush ||
608                      s1_in.uop.fuOpType === LSUOpType.cbo_inval) && !s1_ld_flow
609  val s1_mmio = s1_mmio_cbo
610
611  s1_vaddr_hi         := s1_in.vaddr(VAddrBits - 1, 6)
612  s1_vaddr_lo         := s1_in.vaddr(5, 0)
613  s1_vaddr            := Cat(s1_vaddr_hi, s1_vaddr_lo)
614  s1_paddr_dup_lsu    := io.tlb.resp.bits.paddr(0)
615  s1_paddr_dup_dcache := io.tlb.resp.bits.paddr(1)
616
617  when (s1_tlb_memidx.is_ld && io.tlb.resp.valid && !s1_tlb_miss &&
618        s1_tlb_memidx.idx === s1_in.uop.lqIdx.value && s1_ld_flow) {
619    // printf("Load idx = %d\n", s1_tlb_memidx.idx)
620    s1_out.uop.debugInfo.tlbRespTime := GTimer()
621  } .elsewhen(s1_tlb_memidx.is_st && io.tlb.resp.valid && !s1_tlb_miss &&
622              s1_tlb_memidx.idx === s1_out.uop.sqIdx.value && !s1_ld_flow) {
623    // printf("Store idx = %d\n", s1_tlb_memidx.idx)
624    s1_out.uop.debugInfo.tlbRespTime := GTimer()
625  }
626
627  io.tlb.req_kill   := s1_kill
628  io.tlb.resp.ready := true.B
629
630  io.ldu_io.dcache.s1_paddr_dup_lsu    <> s1_paddr_dup_lsu
631  io.ldu_io.dcache.s1_paddr_dup_dcache <> s1_paddr_dup_dcache
632  io.ldu_io.dcache.s1_kill             := s1_kill || s1_tlb_miss || s1_exception
633
634  // store to load forwarding
635  io.ldu_io.sbuffer.valid := s1_valid && !(s1_exception || s1_tlb_miss || s1_kill || s1_fast_rep_kill || s1_prf || !s1_ld_flow)
636  io.ldu_io.sbuffer.vaddr := s1_vaddr
637  io.ldu_io.sbuffer.paddr := s1_paddr_dup_lsu
638  io.ldu_io.sbuffer.uop   := s1_in.uop
639  io.ldu_io.sbuffer.sqIdx := s1_in.uop.sqIdx
640  io.ldu_io.sbuffer.mask  := s1_in.mask
641  io.ldu_io.sbuffer.pc    := s1_in.uop.pc // FIXME: remove it
642
643  io.ldu_io.lsq.forward.valid     := s1_valid && !(s1_exception || s1_tlb_miss || s1_kill || s1_fast_rep_kill || s1_prf || !s1_ld_flow)
644  io.ldu_io.lsq.forward.vaddr     := s1_vaddr
645  io.ldu_io.lsq.forward.paddr     := s1_paddr_dup_lsu
646  io.ldu_io.lsq.forward.uop       := s1_in.uop
647  io.ldu_io.lsq.forward.sqIdx     := s1_in.uop.sqIdx
648  io.ldu_io.lsq.forward.sqIdxMask := 0.U
649  io.ldu_io.lsq.forward.mask      := s1_in.mask
650  io.ldu_io.lsq.forward.pc        := s1_in.uop.pc // FIXME: remove it
651
652  // st-ld violation query
653  val s1_nuke = VecInit((0 until StorePipelineWidth).map(w => {
654                       io.ldu_io.stld_nuke_query(w).valid && // query valid
655                       isAfter(s1_in.uop.robIdx, io.ldu_io.stld_nuke_query(w).bits.robIdx) && // older store
656                       // TODO: Fix me when vector instruction
657                       (s1_paddr_dup_lsu(PAddrBits-1, 3) === io.ldu_io.stld_nuke_query(w).bits.paddr(PAddrBits-1, 3)) && // paddr match
658                       (s1_in.mask & io.ldu_io.stld_nuke_query(w).bits.mask).orR // data mask contain
659                      })).asUInt.orR && !s1_tlb_miss && s1_ld_flow
660
661  s1_out                   := s1_in
662  s1_out.vaddr             := s1_vaddr
663  s1_out.paddr             := s1_paddr_dup_lsu
664  s1_out.tlbMiss           := s1_tlb_miss
665  s1_out.ptwBack           := io.tlb.resp.bits.ptwBack
666  s1_out.rsIdx             := s1_in.rsIdx
667  s1_out.rep_info.debug    := s1_in.uop.debugInfo
668  s1_out.rep_info.nuke     := s1_nuke && !s1_sw_prf
669  s1_out.lateKill          := s1_late_kill
670
671  when (s1_ld_flow) {
672    when (!s1_late_kill) {
673      // current ori test will cause the case of ldest == 0, below will be modifeid in the future.
674      // af & pf exception were modified
675      s1_out.uop.exceptionVec(loadPageFault)   := io.tlb.resp.bits.excp(0).pf.ld
676      s1_out.uop.exceptionVec(loadAccessFault) := io.tlb.resp.bits.excp(0).af.ld
677    } .otherwise {
678      s1_out.uop.exceptionVec(loadAddrMisaligned) := false.B
679      s1_out.uop.exceptionVec(loadAccessFault)    := s1_late_kill
680    }
681  } .otherwise {
682    s1_out.uop.exceptionVec(storePageFault)   := io.tlb.resp.bits.excp(0).pf.st
683    s1_out.uop.exceptionVec(storeAccessFault) := io.tlb.resp.bits.excp(0).af.st
684  }
685
686  // pointer chasing
687  val s1_try_ptr_chasing       = RegNext(s0_do_try_ptr_chasing, false.B)
688  val s1_ptr_chasing_vaddr     = RegEnable(s0_ptr_chasing_vaddr, s0_do_try_ptr_chasing)
689  val s1_fu_op_type_not_ld     = WireInit(false.B)
690  val s1_not_fast_match        = WireInit(false.B)
691  val s1_addr_mismatch         = WireInit(false.B)
692  val s1_addr_misaligned       = WireInit(false.B)
693  val s1_ptr_chasing_canceled  = WireInit(false.B)
694  val s1_cancel_ptr_chasing    = WireInit(false.B)
695
696  s1_kill := s1_late_kill ||
697             s1_cancel_ptr_chasing ||
698             s1_in.uop.robIdx.needFlush(io.redirect) ||
699             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)
700
701  if (EnableLoadToLoadForward) {
702    // Sometimes, we need to cancel the load-load forwarding.
703    // These can be put at S0 if timing is bad at S1.
704    // Case 0: CACHE_SET(base + offset) != CACHE_SET(base) (lowest 6-bit addition has an overflow)
705    s1_addr_mismatch      := s1_ptr_chasing_vaddr(6) || RegEnable(io.ldu_io.ld_fast_imm(11, 6).orR, s0_do_try_ptr_chasing)
706    // Case 1: the address is misaligned, kill s1
707    s1_addr_misaligned    := LookupTree(s1_in.uop.fuOpType(1, 0), List(
708                             "b00".U   -> false.B,                  //b
709                             "b01".U   -> (s1_vaddr(0)    =/= 0.U), //h
710                             "b10".U   -> (s1_vaddr(1, 0) =/= 0.U), //w
711                             "b11".U   -> (s1_vaddr(2, 0) =/= 0.U)  //d
712                          ))
713    // Case 2: this load-load uop is cancelled
714    s1_ptr_chasing_canceled := !io.lsin.valid
715
716    when (s1_try_ptr_chasing) {
717      s1_cancel_ptr_chasing := s1_addr_mismatch || s1_addr_misaligned || s1_ptr_chasing_canceled
718
719      s1_in.uop           := io.lsin.bits.uop
720      s1_in.rsIdx         := io.lsin.bits.iqIdx
721      s1_in.isFirstIssue  := io.lsin.bits.isFirstIssue
722      s1_vaddr_lo         := s1_ptr_chasing_vaddr(5, 0)
723      s1_paddr_dup_lsu    := Cat(io.tlb.resp.bits.paddr(0)(PAddrBits - 1, 6), s1_vaddr_lo)
724      s1_paddr_dup_dcache := Cat(io.tlb.resp.bits.paddr(0)(PAddrBits - 1, 6), s1_vaddr_lo)
725
726      // 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)
727      s1_in.uop.debugInfo.tlbFirstReqTime := GTimer()
728      s1_in.uop.debugInfo.tlbRespTime     := GTimer()
729    }
730    when (!s1_cancel_ptr_chasing) {
731      s0_ptr_chasing_canceled := s1_try_ptr_chasing && !io.ldu_io.replay.fire && !io.ldu_io.fast_rep_in.fire
732      when (s1_try_ptr_chasing) {
733        io.lsin.ready := true.B
734      }
735    }
736  }
737
738  // pre-calcuate sqIdx mask in s0, then send it to lsq in s1 for forwarding
739  val s1_sqIdx_mask = RegNext(UIntToMask(s0_out.uop.sqIdx.value, StoreQueueSize))
740  // to enable load-load, sqIdxMask must be calculated based on lsin.uop
741  // If the timing here is not OK, load-load forwarding has to be disabled.
742  // Or we calculate sqIdxMask at RS??
743  io.ldu_io.lsq.forward.sqIdxMask := s1_sqIdx_mask
744  if (EnableLoadToLoadForward) {
745    when (s1_try_ptr_chasing) {
746      io.ldu_io.lsq.forward.sqIdxMask := UIntToMask(io.lsin.bits.uop.sqIdx.value, StoreQueueSize)
747    }
748  }
749
750  io.ldu_io.forward_mshr.valid  := s1_valid && s1_out.forward_tlDchannel && s1_ld_flow
751  io.ldu_io.forward_mshr.mshrid := s1_out.mshrid
752  io.ldu_io.forward_mshr.paddr  := s1_out.paddr
753
754  io.stu_io.dcache.s1_kill := s1_tlb_miss || s1_exception || s1_mmio || s1_in.uop.robIdx.needFlush(io.redirect)
755  io.stu_io.dcache.s1_paddr := s1_paddr_dup_dcache
756
757
758  // load debug
759  XSDebug(s1_valid && s1_ld_flow,
760    p"S1: pc ${Hexadecimal(s1_out.uop.pc)}, lId ${Hexadecimal(s1_out.uop.lqIdx.asUInt)}, tlb_miss ${io.tlb.resp.bits.miss}, " +
761    p"paddr ${Hexadecimal(s1_out.paddr)}, mmio ${s1_out.mmio}\n")
762
763  // store debug
764  XSDebug(s1_valid && !s1_ld_flow,
765    p"S1: pc ${Hexadecimal(s1_out.uop.pc)}, lId ${Hexadecimal(s1_out.uop.sqIdx.asUInt)}, tlb_miss ${io.tlb.resp.bits.miss}, " +
766    p"paddr ${Hexadecimal(s1_out.paddr)}, mmio ${s1_out.mmio}\n")
767
768  // store out
769  io.stu_io.lsq.valid         := s1_valid && !s1_ld_flow
770  io.stu_io.lsq.bits          := s1_out
771  io.stu_io.lsq.bits.miss     := s1_tlb_miss
772
773  io.stu_io.issue.valid       := s1_valid && !s1_tlb_miss && !s1_ld_flow
774  io.stu_io.issue.bits        := RegEnable(io.lsin.bits, io.lsin.fire)
775
776  // st-ld violation dectect request
777  io.stu_io.stld_nuke_query.valid       := s1_valid && !s1_tlb_miss && !s1_ld_flow
778  io.stu_io.stld_nuke_query.bits.robIdx := s1_in.uop.robIdx
779  io.stu_io.stld_nuke_query.bits.paddr  := s1_paddr_dup_lsu
780  io.stu_io.stld_nuke_query.bits.mask   := s1_in.mask
781
782  // Pipeline
783  // --------------------------------------------------------------------------------
784  // stage 2
785  // --------------------------------------------------------------------------------
786  // s2: DCache resp
787  val s2_valid  = RegInit(false.B)
788  val s2_in     = Wire(new LqWriteBundle)
789  val s2_out    = Wire(new LqWriteBundle)
790  val s2_kill   = Wire(Bool())
791  val s2_can_go = s3_ready
792  val s2_fire   = s2_valid && !s2_kill && s2_can_go
793
794  s2_kill := s2_in.uop.robIdx.needFlush(io.redirect)
795  s2_ready := !s2_valid || s2_kill || s3_ready
796  when (s1_fire) { s2_valid := true.B }
797  .elsewhen (s2_fire) { s2_valid := false.B }
798  .elsewhen (s2_kill) { s2_valid := false.B }
799  s2_in := RegEnable(s1_out, s1_fire)
800
801  val s2_pmp = WireInit(io.pmp)
802
803  val s2_prf    = s2_in.isPrefetch
804  val s2_hw_prf = s2_in.isHWPrefetch
805  val s2_ld_flow  = RegEnable(s1_ld_flow, s1_fire)
806
807  // exception that may cause load addr to be invalid / illegal
808  // if such exception happen, that inst and its exception info
809  // will be force writebacked to rob
810  val s2_exception_vec = WireInit(s2_in.uop.exceptionVec)
811  when (s2_ld_flow) {
812    when (!s2_in.lateKill) {
813      s2_exception_vec(loadAccessFault) := s2_in.uop.exceptionVec(loadAccessFault) || s2_pmp.ld
814      // soft prefetch will not trigger any exception (but ecc error interrupt may be triggered)
815      when (s2_prf || s2_in.tlbMiss) {
816        s2_exception_vec := 0.U.asTypeOf(s2_exception_vec.cloneType)
817      }
818    }
819  } .otherwise {
820    s2_exception_vec(storeAccessFault) := s2_in.uop.exceptionVec(storeAccessFault) || s2_pmp.st
821    when (s2_prf || s2_in.tlbMiss) {
822      s2_exception_vec := 0.U.asTypeOf(s2_exception_vec.cloneType)
823    }
824  }
825  val s2_ld_exception = ExceptionNO.selectByFu(s2_exception_vec, LduCfg).asUInt.orR && s2_ld_flow
826  val s2_st_exception = ExceptionNO.selectByFu(s2_exception_vec, StaCfg).asUInt.orR && !s2_ld_flow
827  val s2_exception    = s2_ld_exception || s2_st_exception
828
829  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)
830  val (s2_fwd_data_valid, s2_fwd_frm_mshr, s2_fwd_data_frm_mshr) = io.ldu_io.forward_mshr.forward()
831  val s2_fwd_frm_d_chan_or_mshr = s2_fwd_data_valid && (s2_fwd_frm_d_chan || s2_fwd_frm_mshr)
832
833  // writeback access fault caused by ecc error / bus error
834  // * ecc data error is slow to generate, so we will not use it until load stage 3
835  // * in load stage 3, an extra signal io.load_error will be used to
836  val s2_actually_mmio = s2_pmp.mmio
837  val s2_mmio          = !s2_prf &&
838                          s2_actually_mmio &&
839                         !s2_exception &&
840                         !s2_in.tlbMiss
841  val s2_full_fwd      = Wire(Bool())
842  val s2_mem_amb       = s2_in.uop.storeSetHit &&
843                         io.ldu_io.lsq.forward.addrInvalid
844
845  val s2_tlb_miss      = s2_in.tlbMiss
846  val s2_fwd_fail      = io.ldu_io.lsq.forward.dataInvalid
847  val s2_dcache_miss   = io.ldu_io.dcache.resp.bits.miss &&
848                         !s2_fwd_frm_d_chan_or_mshr &&
849                         !s2_full_fwd
850
851  val s2_mq_nack       = io.ldu_io.dcache.s2_mq_nack &&
852                         !s2_fwd_frm_d_chan_or_mshr &&
853                         !s2_full_fwd
854
855  val s2_bank_conflict = io.ldu_io.dcache.s2_bank_conflict &&
856                         !s2_fwd_frm_d_chan_or_mshr &&
857                         !s2_full_fwd
858
859  val s2_wpu_pred_fail = io.ldu_io.dcache.s2_wpu_pred_fail &&
860                        !s2_fwd_frm_d_chan_or_mshr &&
861                        !s2_full_fwd
862
863  val s2_rar_nack      = io.ldu_io.lsq.ldld_nuke_query.req.valid &&
864                         !io.ldu_io.lsq.ldld_nuke_query.req.ready
865
866  val s2_raw_nack      = io.ldu_io.lsq.stld_nuke_query.req.valid &&
867                         !io.ldu_io.lsq.stld_nuke_query.req.ready
868
869  // st-ld violation query
870  //  NeedFastRecovery Valid when
871  //  1. Fast recovery query request Valid.
872  //  2. Load instruction is younger than requestors(store instructions).
873  //  3. Physical address match.
874  //  4. Data contains.
875  val s2_nuke = VecInit((0 until StorePipelineWidth).map(w => {
876                        io.ldu_io.stld_nuke_query(w).valid && // query valid
877                        isAfter(s2_in.uop.robIdx, io.ldu_io.stld_nuke_query(w).bits.robIdx) && // older store
878                        // TODO: Fix me when vector instruction
879                        (s2_in.paddr(PAddrBits-1, 3) === io.ldu_io.stld_nuke_query(w).bits.paddr(PAddrBits-1, 3)) && // paddr match
880                        (s2_in.mask & io.ldu_io.stld_nuke_query(w).bits.mask).orR // data mask contain
881                      })).asUInt.orR && s2_ld_flow || s2_in.rep_info.nuke
882
883  val s2_cache_handled   = io.ldu_io.dcache.resp.bits.handled
884  val s2_cache_tag_error = RegNext(io.csrCtrl.cache_error_enable) &&
885                           io.ldu_io.dcache.resp.bits.tag_error
886
887  val s2_troublem        = !s2_exception &&
888                           !s2_mmio &&
889                           !s2_prf &&
890                           !s2_in.lateKill &&
891                           s2_ld_flow
892
893  io.ldu_io.dcache.resp.ready := true.B
894  io.stu_io.dcache.resp.ready := true.B
895  val s2_dcache_should_resp = !(s2_in.tlbMiss || s2_exception || s2_mmio || s2_prf || s2_in.lateKill) && s2_ld_flow
896  assert(!(s2_valid && (s2_dcache_should_resp && !io.ldu_io.dcache.resp.valid)), "DCache response got lost")
897
898  // fast replay require
899  val s2_dcache_fast_rep = (s2_mq_nack || !s2_dcache_miss && (s2_bank_conflict || s2_wpu_pred_fail))
900  val s2_nuke_fast_rep   = !s2_mq_nack &&
901                           !s2_dcache_miss &&
902                           !s2_bank_conflict &&
903                           !s2_wpu_pred_fail &&
904                           !s2_rar_nack &&
905                           !s2_raw_nack &&
906                           s2_nuke
907
908  val s2_fast_rep = !s2_mem_amb &&
909                    !s2_tlb_miss &&
910                    !s2_fwd_fail &&
911                    (s2_dcache_fast_rep || s2_nuke_fast_rep) &&
912                    s2_troublem
913
914  // need allocate new entry
915  val s2_can_query = !s2_mem_amb &&
916                     !s2_tlb_miss  &&
917                     !s2_fwd_fail &&
918                     !s2_dcache_fast_rep &&
919                     s2_troublem
920
921  val s2_data_fwded = s2_dcache_miss && (s2_full_fwd || s2_cache_tag_error)
922
923  // ld-ld violation require
924  io.ldu_io.lsq.ldld_nuke_query.req.valid           := s2_valid && s2_can_query
925  io.ldu_io.lsq.ldld_nuke_query.req.bits.uop        := s2_in.uop
926  io.ldu_io.lsq.ldld_nuke_query.req.bits.mask       := s2_in.mask
927  io.ldu_io.lsq.ldld_nuke_query.req.bits.paddr      := s2_in.paddr
928  io.ldu_io.lsq.ldld_nuke_query.req.bits.data_valid := Mux(s2_full_fwd || s2_fwd_data_valid, true.B, !s2_dcache_miss)
929
930  // st-ld violation require
931  io.ldu_io.lsq.stld_nuke_query.req.valid           := s2_valid && s2_can_query
932  io.ldu_io.lsq.stld_nuke_query.req.bits.uop        := s2_in.uop
933  io.ldu_io.lsq.stld_nuke_query.req.bits.mask       := s2_in.mask
934  io.ldu_io.lsq.stld_nuke_query.req.bits.paddr      := s2_in.paddr
935  io.ldu_io.lsq.stld_nuke_query.req.bits.data_valid := Mux(s2_full_fwd || s2_fwd_data_valid, true.B, !s2_dcache_miss)
936
937  // merge forward result
938  // lsq has higher priority than sbuffer
939  val s2_fwd_mask = Wire(Vec((VLEN/8), Bool()))
940  val s2_fwd_data = Wire(Vec((VLEN/8), UInt(8.W)))
941  s2_full_fwd := ((~s2_fwd_mask.asUInt).asUInt & s2_in.mask) === 0.U && !io.ldu_io.lsq.forward.dataInvalid
942  // generate XLEN/8 Muxs
943  for (i <- 0 until VLEN / 8) {
944    s2_fwd_mask(i) := io.ldu_io.lsq.forward.forwardMask(i) || io.ldu_io.sbuffer.forwardMask(i)
945    s2_fwd_data(i) := Mux(io.ldu_io.lsq.forward.forwardMask(i), io.ldu_io.lsq.forward.forwardData(i), io.ldu_io.sbuffer.forwardData(i))
946  }
947
948  XSDebug(s2_fire && s2_ld_flow, "[FWD LOAD RESP] pc %x fwd %x(%b) + %x(%b)\n",
949    s2_in.uop.pc,
950    io.ldu_io.lsq.forward.forwardData.asUInt, io.ldu_io.lsq.forward.forwardMask.asUInt,
951    s2_in.forwardData.asUInt, s2_in.forwardMask.asUInt
952  )
953
954  //
955  s2_out                  := s2_in
956  s2_out.data             := 0.U // data will be generated in load s3
957  s2_out.uop.fpWen        := s2_in.uop.fpWen && !s2_exception && s2_ld_flow
958  s2_out.mmio             := s2_mmio
959  s2_out.atomic           := s2_pmp.atomic && !s2_ld_flow
960  s2_out.uop.flushPipe    := false.B
961  s2_out.uop.exceptionVec := s2_exception_vec
962  s2_out.forwardMask      := s2_fwd_mask
963  s2_out.forwardData      := s2_fwd_data
964  s2_out.handledByMSHR    := s2_cache_handled
965  s2_out.miss             := s2_dcache_miss && s2_troublem
966  s2_out.feedbacked       := io.feedback_fast.valid && !io.feedback_fast.bits.hit
967
968  // Generate replay signal caused by:
969  // * st-ld violation check
970  // * tlb miss
971  // * dcache replay
972  // * forward data invalid
973  // * dcache miss
974  s2_out.rep_info.mem_amb         := s2_mem_amb && s2_troublem
975  s2_out.rep_info.tlb_miss        := s2_tlb_miss && s2_troublem
976  s2_out.rep_info.fwd_fail        := s2_fwd_fail && s2_troublem
977  s2_out.rep_info.dcache_rep      := s2_mq_nack && s2_troublem
978  s2_out.rep_info.dcache_miss     := s2_dcache_miss && s2_troublem
979  s2_out.rep_info.bank_conflict   := s2_bank_conflict && s2_troublem
980  s2_out.rep_info.wpu_fail        := s2_wpu_pred_fail && s2_troublem
981  s2_out.rep_info.rar_nack        := s2_rar_nack && s2_troublem
982  s2_out.rep_info.raw_nack        := s2_raw_nack && s2_troublem
983  s2_out.rep_info.nuke            := s2_nuke && s2_troublem
984  s2_out.rep_info.full_fwd        := s2_data_fwded
985  s2_out.rep_info.data_inv_sq_idx := io.ldu_io.lsq.forward.dataInvalidSqIdx
986  s2_out.rep_info.addr_inv_sq_idx := io.ldu_io.lsq.forward.addrInvalidSqIdx
987  s2_out.rep_info.rep_carry       := io.ldu_io.dcache.resp.bits.replayCarry
988  s2_out.rep_info.mshr_id         := io.ldu_io.dcache.resp.bits.mshr_id
989  s2_out.rep_info.last_beat       := s2_in.paddr(log2Up(refillBytes))
990  s2_out.rep_info.debug           := s2_in.uop.debugInfo
991
992  // if forward fail, replay this inst from fetch
993  val debug_fwd_fail_rep = s2_fwd_fail && !s2_troublem && !s2_in.tlbMiss
994  // if ld-ld violation is detected, replay from this inst from fetch
995  val debug_ldld_nuke_rep = false.B // s2_ldld_violation && !s2_mmio && !s2_is_prefetch && !s2_in.tlbMiss
996  // io.out.bits.uop.replayInst := false.B
997
998  // to be removed
999  val s2_ld_need_fb = !s2_in.isLoadReplay &&      // already feedbacked
1000                      io.ldu_io.lq_rep_full &&           // LoadQueueReplay is full
1001                      s2_out.rep_info.need_rep && // need replay
1002                      !s2_exception &&            // no exception is triggered
1003                      !s2_hw_prf                  // not hardware prefetch
1004  val s2_st_need_fb = !s2_ld_flow
1005  io.feedback_fast.valid                 := s2_valid && (s2_ld_need_fb || s2_st_need_fb)
1006  io.feedback_fast.bits.hit              := Mux(s2_ld_flow, false.B, !s2_tlb_miss)
1007  io.feedback_fast.bits.flushState       := s2_in.ptwBack
1008  io.feedback_fast.bits.robIdx           := s2_in.uop.robIdx
1009  io.feedback_fast.bits.sourceType       := Mux(s2_ld_flow, RSFeedbackType.lrqFull, RSFeedbackType.tlbMiss)
1010  io.feedback_fast.bits.dataInvalidSqIdx := DontCare
1011
1012  io.stu_io.lsq_replenish := s2_out
1013  io.stu_io.lsq_replenish.miss := io.ldu_io.dcache.resp.fire && io.ldu_io.dcache.resp.bits.miss
1014
1015  io.ldu_io.ldCancel.ld1Cancel.valid := s2_valid && (
1016    (s2_out.rep_info.need_rep && s2_out.isFirstIssue) ||                // exe fail and issued from IQ
1017    s2_mmio                                                             // is mmio
1018  ) && s2_ld_flow
1019  io.ldu_io.ldCancel.ld1Cancel.bits := s2_out.deqPortIdx
1020
1021  // fast wakeup
1022  io.ldu_io.fast_uop.valid := RegNext(
1023    !io.ldu_io.dcache.s1_disable_fast_wakeup &&
1024    s1_valid &&
1025    !s1_kill &&
1026    !io.tlb.resp.bits.miss &&
1027    !io.ldu_io.lsq.forward.dataInvalidFast
1028  ) && (s2_valid && !s2_out.rep_info.need_rep && !s2_mmio && s2_ld_flow)
1029  io.ldu_io.fast_uop.bits := RegNext(s1_out.uop)
1030
1031  //
1032  io.ldu_io.s2_ptr_chasing                    := RegEnable(s1_try_ptr_chasing && !s1_cancel_ptr_chasing, false.B, s1_fire)
1033
1034  // prefetch train
1035  io.prefetch_train.valid              := s2_valid && !s2_actually_mmio && !s2_in.tlbMiss
1036  io.prefetch_train.bits.fromLsPipelineBundle(s2_in)
1037  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?
1038  io.prefetch_train.bits.meta_prefetch := Mux(s2_ld_flow, io.ldu_io.dcache.resp.bits.meta_prefetch, false.B)
1039  io.prefetch_train.bits.meta_access   := Mux(s2_ld_flow, io.ldu_io.dcache.resp.bits.meta_access, false.B)
1040
1041  io.prefetch_train_l1.valid              := s2_valid && !s2_actually_mmio && s2_ld_flow
1042  io.prefetch_train_l1.bits.fromLsPipelineBundle(s2_in)
1043  io.prefetch_train_l1.bits.miss          := io.ldu_io.dcache.resp.bits.miss
1044  io.prefetch_train_l1.bits.meta_prefetch := io.ldu_io.dcache.resp.bits.meta_prefetch
1045  io.prefetch_train_l1.bits.meta_access   := io.ldu_io.dcache.resp.bits.meta_access
1046  if (env.FPGAPlatform){
1047    io.ldu_io.dcache.s0_pc := DontCare
1048    io.ldu_io.dcache.s1_pc := DontCare
1049    io.ldu_io.dcache.s2_pc := DontCare
1050  }else{
1051    io.ldu_io.dcache.s0_pc := s0_out.uop.pc
1052    io.ldu_io.dcache.s1_pc := s1_out.uop.pc
1053    io.ldu_io.dcache.s2_pc := s2_out.uop.pc
1054  }
1055  io.ldu_io.dcache.s2_kill := s2_pmp.ld  || s2_actually_mmio || s2_kill
1056  io.stu_io.dcache.s2_kill := s2_pmp.st || s2_actually_mmio || s2_kill
1057  io.stu_io.dcache.s2_pc := s2_out.uop.pc
1058
1059  val s1_ld_left_fire = s1_valid && !s1_kill && s2_ready && s1_ld_flow
1060  val s2_ld_valid_dup = RegInit(0.U(6.W))
1061  s2_ld_valid_dup := 0x0.U(6.W)
1062  when (s1_ld_left_fire && !s1_out.isHWPrefetch && s1_ld_flow) { s2_ld_valid_dup := 0x3f.U(6.W) }
1063  when (s1_kill || s1_out.isHWPrefetch || !s1_ld_flow) { s2_ld_valid_dup := 0x0.U(6.W) }
1064  assert(RegNext((s2_valid === s2_ld_valid_dup(0)) || RegNext(s1_out.isHWPrefetch) || RegNext(!s1_ld_flow)))
1065
1066  // Pipeline
1067  // --------------------------------------------------------------------------------
1068  // stage 3
1069  // --------------------------------------------------------------------------------
1070  // writeback and update load queue
1071  val s3_valid        = RegNext(s2_valid && !s2_out.isHWPrefetch && !s2_out.uop.robIdx.needFlush(io.redirect))
1072  val s3_in           = RegEnable(s2_out, s2_fire)
1073  val s3_out          = Wire(Valid(new MemExuOutput))
1074  val s3_dcache_rep   = RegEnable(s2_dcache_fast_rep && s2_troublem, false.B, s2_fire)
1075  val s3_ld_valid_dup = RegEnable(s2_ld_valid_dup, s2_fire)
1076  val s3_fast_rep     = Wire(Bool())
1077  val s3_ld_flow      = RegNext(s2_ld_flow)
1078  val s3_troublem     = RegNext(s2_troublem)
1079  val s3_kill         = s3_in.uop.robIdx.needFlush(io.redirect)
1080  s3_ready := !s3_valid || s3_kill || sx_can_go
1081
1082  // forwrad last beat
1083  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)
1084  val s3_fwd_data_valid = RegEnable(s2_fwd_data_valid, false.B, s2_valid)
1085  val s3_fwd_frm_d_chan_valid = (s3_fwd_frm_d_chan && s3_fwd_data_valid) && s3_ld_flow
1086
1087
1088  // s3 load fast replay
1089  io.ldu_io.fast_rep_out.valid := s3_valid &&
1090                                  s3_fast_rep &&
1091                                  !s3_in.uop.robIdx.needFlush(io.redirect) &&
1092                                  s3_ld_flow
1093  io.ldu_io.fast_rep_out.bits := s3_in
1094
1095  io.ldu_io.lsq.ldin.valid := s3_valid &&
1096                              (!s3_fast_rep || !io.ldu_io.fast_rep_out.ready) &&
1097                              !s3_in.feedbacked &&
1098                              !s3_in.lateKill &&
1099                              s3_ld_flow
1100  io.ldu_io.lsq.ldin.bits := s3_in
1101  io.ldu_io.lsq.ldin.bits.miss := s3_in.miss && !s3_fwd_frm_d_chan_valid
1102
1103  /* <------- DANGEROUS: Don't change sequence here ! -------> */
1104  io.ldu_io.lsq.ldin.bits.data_wen_dup := s3_ld_valid_dup.asBools
1105  io.ldu_io.lsq.ldin.bits.replacementUpdated := io.ldu_io.dcache.resp.bits.replacementUpdated
1106  io.ldu_io.lsq.ldin.bits.missDbUpdated := RegNext(s2_fire && s2_in.hasROBEntry && !s2_in.tlbMiss && !s2_in.missDbUpdated)
1107
1108  val s3_dly_ld_err =
1109    if (EnableAccurateLoadError) {
1110      (s3_in.lateKill || io.ldu_io.dcache.resp.bits.error_delayed) && RegNext(io.csrCtrl.cache_error_enable)
1111    } else {
1112      WireInit(false.B)
1113    }
1114  io.ldu_io.s3_dly_ld_err := false.B // s3_dly_ld_err && s3_valid
1115  io.ldu_io.fast_rep_out.bits.delayedLoadError := s3_dly_ld_err
1116  io.ldu_io.lsq.ldin.bits.dcacheRequireReplay  := s3_dcache_rep
1117
1118  val s3_vp_match_fail = RegNext(io.ldu_io.lsq.forward.matchInvalid || io.ldu_io.sbuffer.matchInvalid) && s3_troublem
1119  val s3_ldld_rep_inst =
1120      io.ldu_io.lsq.ldld_nuke_query.resp.valid &&
1121      io.ldu_io.lsq.ldld_nuke_query.resp.bits.rep_frm_fetch &&
1122      RegNext(io.csrCtrl.ldld_vio_check_enable)
1123
1124  val s3_rep_info = WireInit(s3_in.rep_info)
1125  s3_rep_info.dcache_miss   := s3_in.rep_info.dcache_miss && !s3_fwd_frm_d_chan_valid && s3_troublem
1126  val s3_rep_frm_fetch = s3_vp_match_fail || s3_ldld_rep_inst
1127  val s3_sel_rep_cause = PriorityEncoderOH(s3_rep_info.cause.asUInt)
1128  val s3_force_rep     = s3_sel_rep_cause(LoadReplayCauses.C_TM) &&
1129                         !s3_in.uop.exceptionVec(loadAddrMisaligned) &&
1130                         s3_troublem
1131
1132  val s3_ld_exception = ExceptionNO.selectByFu(s3_in.uop.exceptionVec, LduCfg).asUInt.orR && s3_ld_flow
1133  val s3_st_exception = ExceptionNO.selectByFu(s3_in.uop.exceptionVec, StaCfg).asUInt.orR && !s3_ld_flow
1134  val s3_exception    = s3_ld_exception || s3_st_exception
1135  when ((s3_ld_exception || s3_dly_ld_err || s3_rep_frm_fetch) && !s3_force_rep) {
1136    io.ldu_io.lsq.ldin.bits.rep_info.cause := 0.U.asTypeOf(s3_rep_info.cause.cloneType)
1137  } .otherwise {
1138    io.ldu_io.lsq.ldin.bits.rep_info.cause := VecInit(s3_sel_rep_cause.asBools)
1139  }
1140
1141  // Int flow, if hit, will be writebacked at s3
1142  s3_out.valid                := s3_valid &&
1143                                (!s3_ld_flow && !s3_in.feedbacked || !io.ldu_io.lsq.ldin.bits.rep_info.need_rep && !s3_in.mmio)
1144  s3_out.bits.uop             := s3_in.uop
1145  s3_out.bits.uop.exceptionVec(loadAccessFault) := (s3_dly_ld_err  || s3_in.uop.exceptionVec(loadAccessFault)) && s3_ld_flow
1146  s3_out.bits.uop.replayInst := s3_rep_frm_fetch
1147  s3_out.bits.data            := s3_in.data
1148  s3_out.bits.debug.isMMIO    := s3_in.mmio
1149  s3_out.bits.debug.isPerfCnt := false.B
1150  s3_out.bits.debug.paddr     := s3_in.paddr
1151  s3_out.bits.debug.vaddr     := s3_in.vaddr
1152
1153  when (s3_force_rep) {
1154    s3_out.bits.uop.exceptionVec := 0.U.asTypeOf(s3_in.uop.exceptionVec.cloneType)
1155  }
1156
1157  /* <------- DANGEROUS: Don't change sequence here ! -------> */
1158  io.ldu_io.lsq.ldin.bits.uop := s3_out.bits.uop
1159
1160  val s3_revoke = s3_exception || io.ldu_io.lsq.ldin.bits.rep_info.need_rep
1161  io.ldu_io.lsq.ldld_nuke_query.revoke := s3_revoke
1162  io.ldu_io.lsq.stld_nuke_query.revoke := s3_revoke
1163
1164  // feedback slow
1165  s3_fast_rep := RegNext(s2_fast_rep) &&
1166                 !s3_in.feedbacked &&
1167                 !s3_in.lateKill &&
1168                 !s3_rep_frm_fetch &&
1169                 !s3_exception
1170
1171  val s3_fb_no_waiting = !s3_in.isLoadReplay && !(s3_fast_rep && io.ldu_io.fast_rep_out.ready) && !s3_in.feedbacked
1172
1173  //
1174  io.feedback_slow.valid                 := s3_valid && !s3_in.uop.robIdx.needFlush(io.redirect) && s3_fb_no_waiting && s3_ld_flow
1175  io.feedback_slow.bits.hit              := !io.ldu_io.lsq.ldin.bits.rep_info.need_rep || io.ldu_io.lsq.ldin.ready
1176  io.feedback_slow.bits.flushState       := s3_in.ptwBack
1177  io.feedback_slow.bits.robIdx           := s3_in.uop.robIdx
1178  io.feedback_slow.bits.sourceType       := RSFeedbackType.lrqFull
1179  io.feedback_slow.bits.dataInvalidSqIdx := DontCare
1180
1181  io.ldu_io.ldCancel.ld2Cancel.valid := s3_valid && (
1182    (io.ldu_io.lsq.ldin.bits.rep_info.need_rep && s3_in.isFirstIssue) ||
1183    s3_in.mmio
1184  ) && s3_ld_flow
1185  io.ldu_io.ldCancel.ld2Cancel.bits := s3_in.deqPortIdx
1186
1187  // data from dcache hit
1188  val s3_ld_raw_data_frm_cache = Wire(new LoadDataFromDcacheBundle)
1189  s3_ld_raw_data_frm_cache.respDcacheData       := io.ldu_io.dcache.resp.bits.data_delayed
1190  s3_ld_raw_data_frm_cache.forwardMask          := RegEnable(s2_fwd_mask, s2_valid)
1191  s3_ld_raw_data_frm_cache.forwardData          := RegEnable(s2_fwd_data, s2_valid)
1192  s3_ld_raw_data_frm_cache.uop                  := RegEnable(s2_out.uop, s2_valid)
1193  s3_ld_raw_data_frm_cache.addrOffset           := RegEnable(s2_out.paddr(3, 0), s2_valid)
1194  s3_ld_raw_data_frm_cache.forward_D            := RegEnable(s2_fwd_frm_d_chan, false.B, s2_valid) || s3_fwd_frm_d_chan_valid
1195  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))
1196  s3_ld_raw_data_frm_cache.forward_mshr         := RegEnable(s2_fwd_frm_mshr, false.B, s2_valid)
1197  s3_ld_raw_data_frm_cache.forwardData_mshr     := RegEnable(s2_fwd_data_frm_mshr, s2_valid)
1198  s3_ld_raw_data_frm_cache.forward_result_valid := RegEnable(s2_fwd_data_valid, false.B, s2_valid)
1199
1200  val s3_merged_data_frm_cache = s3_ld_raw_data_frm_cache.mergedData()
1201  val s3_picked_data_frm_cache = LookupTree(s3_ld_raw_data_frm_cache.addrOffset, List(
1202    "b0000".U -> s3_merged_data_frm_cache(63,    0),
1203    "b0001".U -> s3_merged_data_frm_cache(63,    8),
1204    "b0010".U -> s3_merged_data_frm_cache(63,   16),
1205    "b0011".U -> s3_merged_data_frm_cache(63,   24),
1206    "b0100".U -> s3_merged_data_frm_cache(63,   32),
1207    "b0101".U -> s3_merged_data_frm_cache(63,   40),
1208    "b0110".U -> s3_merged_data_frm_cache(63,   48),
1209    "b0111".U -> s3_merged_data_frm_cache(63,   56),
1210    "b1000".U -> s3_merged_data_frm_cache(127,  64),
1211    "b1001".U -> s3_merged_data_frm_cache(127,  72),
1212    "b1010".U -> s3_merged_data_frm_cache(127,  80),
1213    "b1011".U -> s3_merged_data_frm_cache(127,  88),
1214    "b1100".U -> s3_merged_data_frm_cache(127,  96),
1215    "b1101".U -> s3_merged_data_frm_cache(127, 104),
1216    "b1110".U -> s3_merged_data_frm_cache(127, 112),
1217    "b1111".U -> s3_merged_data_frm_cache(127, 120)
1218  ))
1219  val s3_ld_data_frm_cache = rdataHelper(s3_ld_raw_data_frm_cache.uop, s3_picked_data_frm_cache)
1220
1221  // FIXME: add 1 cycle delay ?
1222  io.ldout.bits      := s3_out.bits
1223  io.ldout.bits.data := s3_ld_data_frm_cache
1224  io.ldout.valid     := s3_out.valid && !s3_out.bits.uop.robIdx.needFlush(io.redirect) && s3_ld_flow
1225
1226  // for uncache
1227  io.ldu_io.lsq.uncache.ready := true.B
1228
1229  // fast load to load forward
1230  io.ldu_io.l2l_fwd_out.valid      := s3_out.valid && !s3_in.lateKill && s3_ld_flow
1231  io.ldu_io.l2l_fwd_out.data       := s3_ld_data_frm_cache
1232  io.ldu_io.l2l_fwd_out.dly_ld_err := s3_dly_ld_err // ecc delayed error
1233
1234  // hybrid unit writeback to rob
1235  // delay params
1236  val SelectGroupSize   = RollbackGroupSize
1237  val lgSelectGroupSize = log2Ceil(SelectGroupSize)
1238  val TotalSelectCycles = scala.math.ceil(log2Ceil(LoadQueueRAWSize).toFloat / lgSelectGroupSize).toInt + 1
1239  val TotalDelayCycles  = TotalSelectCycles - 2
1240
1241  // writeback
1242  val sx_valid = Wire(Vec(TotalDelayCycles + 1, Bool()))
1243  val sx_ready = Wire(Vec(TotalDelayCycles + 1, Bool()))
1244  val sx_in    = Wire(Vec(TotalDelayCycles + 1, new MemExuOutput))
1245
1246  sx_can_go := sx_ready.head
1247  for (i <- 0 until TotalDelayCycles + 1) {
1248    if (i == 0) {
1249      sx_valid(i) := s3_valid && !s3_ld_flow && !s3_in.feedbacked
1250      sx_in(i)    := s3_out.bits
1251      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))
1252    } else {
1253      val cur_kill   = sx_in(i).uop.robIdx.needFlush(io.redirect)
1254      val cur_can_go = (if (i == TotalDelayCycles) io.stout.ready else sx_ready(i+1))
1255      val cur_fire   = sx_valid(i) && !cur_kill && cur_can_go
1256      val prev_fire  = sx_valid(i-1) && !sx_in(i-1).uop.robIdx.needFlush(io.redirect) && sx_ready(i)
1257
1258      sx_ready(i) := !sx_valid(i) || cur_kill || (if (i == TotalDelayCycles) io.stout.ready else sx_ready(i+1))
1259      val sx_valid_can_go = prev_fire || cur_fire || cur_kill
1260      sx_valid(i) := RegEnable(Mux(prev_fire, true.B, false.B), sx_valid_can_go)
1261      sx_in(i) := RegEnable(sx_in(i-1), prev_fire)
1262    }
1263  }
1264
1265  val sx_last_valid = sx_valid.takeRight(1).head
1266  val sx_last_ready = sx_ready.takeRight(1).head
1267  val sx_last_in    = sx_in.takeRight(1).head
1268
1269  sx_last_ready  := !sx_last_valid || sx_last_in.uop.robIdx.needFlush(io.redirect) || io.stout.ready
1270  io.stout.valid := sx_last_valid && !sx_last_in.uop.robIdx.needFlush(io.redirect)
1271  io.stout.bits  := sx_last_in
1272
1273   // trigger
1274  val ld_trigger = FuType.isLoad(io.ldout.bits.uop.fuType)
1275  val last_valid_data = RegEnable(io.ldout.bits.data, io.stout.fire)
1276  val hit_ld_addr_trig_hit_vec = Wire(Vec(3, Bool()))
1277  val lq_ld_addr_trig_hit_vec = RegNext(io.ldu_io.lsq.trigger.lqLoadAddrTriggerHitVec)
1278  (0 until 3).map{i => {
1279    val tdata2    = RegNext(RegNext(io.ldu_io.trigger(i).tdata2))
1280    val matchType = RegNext(RegNext(io.ldu_io.trigger(i).matchType))
1281    val tEnable   = RegNext(RegNext(io.ldu_io.trigger(i).tEnable))
1282
1283    hit_ld_addr_trig_hit_vec(i)        := TriggerCmp(RegNext(s3_in.vaddr), tdata2, matchType, tEnable)
1284    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))
1285    io.ldu_io.trigger(i).lastDataHit   := TriggerCmp(last_valid_data, tdata2, matchType, tEnable)
1286  }}
1287  io.ldu_io.lsq.trigger.hitLoadAddrTriggerHitVec := hit_ld_addr_trig_hit_vec
1288
1289  // FIXME: please move this part to LoadQueueReplay
1290  io.ldu_io.debug_ls := DontCare
1291  io.stu_io.debug_ls := DontCare
1292  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
1293  io.stu_io.debug_ls.s1_robIdx := s1_in.uop.robIdx.value
1294
1295 // Topdown
1296  io.ldu_io.lsTopdownInfo.s1.robIdx          := s1_in.uop.robIdx.value
1297  io.ldu_io.lsTopdownInfo.s1.vaddr_valid     := s1_valid && s1_in.hasROBEntry
1298  io.ldu_io.lsTopdownInfo.s1.vaddr_bits      := s1_vaddr
1299  io.ldu_io.lsTopdownInfo.s2.robIdx          := s2_in.uop.robIdx.value
1300  io.ldu_io.lsTopdownInfo.s2.paddr_valid     := s2_fire && s2_in.hasROBEntry && !s2_in.tlbMiss
1301  io.ldu_io.lsTopdownInfo.s2.paddr_bits      := s2_in.paddr
1302  io.ldu_io.lsTopdownInfo.s2.first_real_miss := io.ldu_io.dcache.resp.bits.real_miss
1303  io.ldu_io.lsTopdownInfo.s2.cache_miss_en   := s2_fire && s2_in.hasROBEntry && !s2_in.tlbMiss && !s2_in.missDbUpdated
1304
1305  // perf cnt
1306  XSPerfAccumulate("s0_in_valid",                  io.lsin.valid)
1307  XSPerfAccumulate("s0_in_block",                  io.lsin.valid && !io.lsin.fire)
1308  XSPerfAccumulate("s0_in_fire_first_issue",       s0_valid && s0_isFirstIssue)
1309  XSPerfAccumulate("s0_lsq_fire_first_issue",      io.ldu_io.replay.fire)
1310  XSPerfAccumulate("s0_ldu_fire_first_issue",      io.lsin.fire && s0_isFirstIssue)
1311  XSPerfAccumulate("s0_fast_replay_issue",         io.ldu_io.fast_rep_in.fire)
1312  XSPerfAccumulate("s0_stall_out",                 s0_valid && !s0_can_go)
1313  XSPerfAccumulate("s0_stall_ld_dcache",           s0_valid && !io.ldu_io.dcache.req.ready)
1314  XSPerfAccumulate("s0_stall_st_dcache",           s0_valid && !io.stu_io.dcache.req.ready)
1315  XSPerfAccumulate("s0_addr_spec_success",         s0_fire && s0_vaddr(VAddrBits-1, 12) === io.lsin.bits.src(0)(VAddrBits-1, 12))
1316  XSPerfAccumulate("s0_addr_spec_failed",          s0_fire && s0_vaddr(VAddrBits-1, 12) =/= io.lsin.bits.src(0)(VAddrBits-1, 12))
1317  XSPerfAccumulate("s0_addr_spec_success_once",    s0_fire && s0_vaddr(VAddrBits-1, 12) === io.lsin.bits.src(0)(VAddrBits-1, 12) && s0_isFirstIssue)
1318  XSPerfAccumulate("s0_addr_spec_failed_once",     s0_fire && s0_vaddr(VAddrBits-1, 12) =/= io.lsin.bits.src(0)(VAddrBits-1, 12) && s0_isFirstIssue)
1319  XSPerfAccumulate("s0_forward_tl_d_channel",      s0_out.forward_tlDchannel)
1320  XSPerfAccumulate("s0_hardware_prefetch_fire",    s0_fire && s0_hw_prf_select)
1321  XSPerfAccumulate("s0_software_prefetch_fire",    s0_fire && s0_prf && s0_int_iss_select)
1322  XSPerfAccumulate("s0_hardware_prefetch_blocked", io.ldu_io.prefetch_req.valid && !s0_hw_prf_select)
1323  XSPerfAccumulate("s0_hardware_prefetch_total",   io.ldu_io.prefetch_req.valid)
1324
1325  XSPerfAccumulate("s1_in_valid",                  s1_valid)
1326  XSPerfAccumulate("s1_in_fire",                   s1_fire)
1327  XSPerfAccumulate("s1_in_fire_first_issue",       s1_fire && s1_in.isFirstIssue)
1328  XSPerfAccumulate("s1_tlb_miss",                  s1_fire && s1_tlb_miss)
1329  XSPerfAccumulate("s1_tlb_miss_first_issue",      s1_fire && s1_tlb_miss && s1_in.isFirstIssue)
1330  XSPerfAccumulate("s1_stall_out",                 s1_valid && !s1_can_go)
1331  XSPerfAccumulate("s1_late_kill",                 s1_valid && s1_fast_rep_kill)
1332
1333  XSPerfAccumulate("s2_in_valid",                  s2_valid)
1334  XSPerfAccumulate("s2_in_fire",                   s2_fire)
1335  XSPerfAccumulate("s2_in_fire_first_issue",       s2_fire && s2_in.isFirstIssue)
1336  XSPerfAccumulate("s2_dcache_miss",               s2_fire && io.ldu_io.dcache.resp.bits.miss)
1337  XSPerfAccumulate("s2_dcache_miss_first_issue",   s2_fire && io.ldu_io.dcache.resp.bits.miss && s2_in.isFirstIssue)
1338  XSPerfAccumulate("s2_dcache_real_miss_first_issue",   s2_fire && io.ldu_io.dcache.resp.bits.miss && s2_in.isFirstIssue)
1339  XSPerfAccumulate("s2_full_forward",              s2_fire && s2_full_fwd)
1340  XSPerfAccumulate("s2_dcache_miss_full_forward",  s2_fire && s2_dcache_miss)
1341  XSPerfAccumulate("s2_fwd_frm_d_can",             s2_valid && s2_fwd_frm_d_chan)
1342  XSPerfAccumulate("s2_fwd_frm_d_chan_or_mshr",    s2_valid && s2_fwd_frm_d_chan_or_mshr)
1343  XSPerfAccumulate("s2_stall_out",                 s2_fire && !s2_can_go)
1344  XSPerfAccumulate("s2_prefetch",                  s2_fire && s2_prf)
1345  XSPerfAccumulate("s2_prefetch_ignored",          s2_fire && s2_prf && s2_mq_nack) // ignore prefetch for mshr full / miss req port conflict
1346  XSPerfAccumulate("s2_prefetch_miss",             s2_fire && s2_prf && io.ldu_io.dcache.resp.bits.miss) // prefetch req miss in l1
1347  XSPerfAccumulate("s2_prefetch_hit",              s2_fire && s2_prf && !io.ldu_io.dcache.resp.bits.miss) // prefetch req hit in l1
1348  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
1349  XSPerfAccumulate("s2_forward_req",               s2_fire && s2_in.forward_tlDchannel)
1350  XSPerfAccumulate("s2_successfully_forward_channel_D", s2_fire && s2_fwd_frm_d_chan && s2_fwd_data_valid)
1351  XSPerfAccumulate("s2_successfully_forward_mshr",      s2_fire && s2_fwd_frm_mshr && s2_fwd_data_valid)
1352
1353  XSPerfAccumulate("s3_fwd_frm_d_chan",            s3_valid && s3_fwd_frm_d_chan_valid)
1354
1355  XSPerfAccumulate("load_to_load_forward",                      s1_try_ptr_chasing && !s1_ptr_chasing_canceled)
1356  XSPerfAccumulate("load_to_load_forward_try",                  s1_try_ptr_chasing)
1357  XSPerfAccumulate("load_to_load_forward_fail",                 s1_cancel_ptr_chasing)
1358  XSPerfAccumulate("load_to_load_forward_fail_cancelled",       s1_cancel_ptr_chasing && s1_ptr_chasing_canceled)
1359  XSPerfAccumulate("load_to_load_forward_fail_wakeup_mismatch", s1_cancel_ptr_chasing && !s1_ptr_chasing_canceled && s1_not_fast_match)
1360  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)
1361  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)
1362  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)
1363
1364  // bug lyq: some signals in perfEvents are no longer suitable for the current MemBlock design
1365  // hardware performance counter
1366  val perfEvents = Seq(
1367    ("load_s0_in_fire         ", s0_fire                                                        ),
1368    ("load_to_load_forward    ", s1_fire && s1_try_ptr_chasing && !s1_ptr_chasing_canceled      ),
1369    ("stall_dcache            ", s0_valid && s0_can_go && !io.ldu_io.dcache.req.ready           ),
1370    ("load_s1_in_fire         ", s0_fire                                                        ),
1371    ("load_s1_tlb_miss        ", s1_fire && io.tlb.resp.bits.miss                               ),
1372    ("load_s2_in_fire         ", s1_fire                                                        ),
1373    ("load_s2_dcache_miss     ", s2_fire && io.ldu_io.dcache.resp.bits.miss                     ),
1374  )
1375  generatePerfEvent()
1376}