xref: /XiangShan/src/main/scala/xiangshan/mem/pipeline/StoreUnit.scala (revision 3b739f49c5a26805be859c7231717ecc38aade30)
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 chipsalliance.rocketchip.config.Parameters
20import chisel3._
21import chisel3.util._
22import utils._
23import utility._
24import xiangshan.ExceptionNO._
25import xiangshan._
26import xiangshan.backend.fu.PMPRespBundle
27import xiangshan.cache.mmu.{TlbCmd, TlbReq, TlbRequestIO, TlbResp}
28import xiangshan.v2backend.Bundles.{MemExuInput, MemExuOutput}
29import xiangshan.v2backend.{StaCfg}
30
31// Store Pipeline Stage 0
32// Generate addr, use addr to query DCache and DTLB
33class StoreUnit_S0(implicit p: Parameters) extends XSModule {
34  val io = IO(new Bundle() {
35    val in = Flipped(Decoupled(new MemExuInput))
36    val rsIdx = Input(UInt(log2Up(IssQueSize).W))
37    val isFirstIssue = Input(Bool())
38    val out = Decoupled(new LsPipelineBundle)
39    val dtlbReq = DecoupledIO(new TlbReq)
40  })
41
42  // send req to dtlb
43  // val saddr = io.in.bits.src(0) + SignExt(io.in.bits.uop.ctrl.imm(11,0), VAddrBits)
44  val imm12 = WireInit(io.in.bits.uop.imm(11,0))
45  val saddr_lo = io.in.bits.src(0)(11,0) + Cat(0.U(1.W), imm12)
46  val saddr_hi = Mux(saddr_lo(12),
47    Mux(imm12(11), io.in.bits.src(0)(VAddrBits-1, 12), io.in.bits.src(0)(VAddrBits-1, 12)+1.U),
48    Mux(imm12(11), io.in.bits.src(0)(VAddrBits-1, 12)+SignExt(1.U, VAddrBits-12), io.in.bits.src(0)(VAddrBits-1, 12)),
49  )
50  val saddr = Cat(saddr_hi, saddr_lo(11,0))
51
52  io.dtlbReq.bits.vaddr := saddr
53  io.dtlbReq.valid := io.in.valid
54  io.dtlbReq.bits.cmd := TlbCmd.write
55  io.dtlbReq.bits.size := LSUOpType.size(io.in.bits.uop.fuOpType)
56  io.dtlbReq.bits.kill := DontCare
57  io.dtlbReq.bits.debug.robIdx := io.in.bits.uop.robIdx
58  io.dtlbReq.bits.debug.pc := io.in.bits.uop.pc
59  io.dtlbReq.bits.debug.isFirstIssue := io.isFirstIssue
60
61  io.out.bits := DontCare
62  io.out.bits.vaddr := saddr
63
64  // Now data use its own io
65  // io.out.bits.data := genWdata(io.in.bits.src(1), io.in.bits.uop.ctrl.fuOpType(1,0))
66  io.out.bits.data := io.in.bits.src(1) // FIXME: remove data from pipeline
67  io.out.bits.uop := io.in.bits.uop
68  io.out.bits.miss := DontCare
69  io.out.bits.rsIdx := io.rsIdx
70  io.out.bits.mask := genWmask(io.out.bits.vaddr, io.in.bits.uop.fuOpType(1,0))
71  io.out.bits.isFirstIssue := io.isFirstIssue
72  io.out.bits.wlineflag := io.in.bits.uop.fuOpType === LSUOpType.cbo_zero
73  io.out.valid := io.in.valid
74  io.in.ready := io.out.ready
75
76  // exception check
77  val addrAligned = LookupTree(io.in.bits.uop.fuOpType(1,0), List(
78    "b00".U   -> true.B,              //b
79    "b01".U   -> (io.out.bits.vaddr(0) === 0.U),   //h
80    "b10".U   -> (io.out.bits.vaddr(1,0) === 0.U), //w
81    "b11".U   -> (io.out.bits.vaddr(2,0) === 0.U)  //d
82  ))
83
84  io.out.bits.uop.exceptionVec(storeAddrMisaligned) := !addrAligned
85
86  XSPerfAccumulate("in_valid", io.in.valid)
87  XSPerfAccumulate("in_fire", io.in.fire)
88  XSPerfAccumulate("in_fire_first_issue", io.in.fire && io.isFirstIssue)
89  XSPerfAccumulate("addr_spec_success", io.out.fire() && saddr(VAddrBits-1, 12) === io.in.bits.src(0)(VAddrBits-1, 12))
90  XSPerfAccumulate("addr_spec_failed", io.out.fire() && saddr(VAddrBits-1, 12) =/= io.in.bits.src(0)(VAddrBits-1, 12))
91  XSPerfAccumulate("addr_spec_success_once", io.out.fire() && saddr(VAddrBits-1, 12) === io.in.bits.src(0)(VAddrBits-1, 12) && io.isFirstIssue)
92  XSPerfAccumulate("addr_spec_failed_once", io.out.fire() && saddr(VAddrBits-1, 12) =/= io.in.bits.src(0)(VAddrBits-1, 12) && io.isFirstIssue)
93}
94
95// Store Pipeline Stage 1
96// TLB resp (send paddr to dcache)
97class StoreUnit_S1(implicit p: Parameters) extends XSModule {
98  val io = IO(new Bundle() {
99    val in = Flipped(Decoupled(new LsPipelineBundle))
100    val out = Decoupled(new LsPipelineBundle)
101    val lsq = ValidIO(new LsPipelineBundle())
102    val dtlbResp = Flipped(DecoupledIO(new TlbResp()))
103    val rsFeedback = ValidIO(new RSFeedback)
104    val reExecuteQuery = Valid(new LoadReExecuteQueryIO)
105  })
106
107  // mmio cbo decoder
108  val is_mmio_cbo = io.in.bits.uop.fuOpType === LSUOpType.cbo_clean ||
109    io.in.bits.uop.fuOpType === LSUOpType.cbo_flush ||
110    io.in.bits.uop.fuOpType === LSUOpType.cbo_inval
111
112  val s1_paddr = io.dtlbResp.bits.paddr(0)
113  val s1_tlb_miss = io.dtlbResp.bits.miss
114  val s1_mmio = is_mmio_cbo
115  val s1_exception = ExceptionNO.selectByFu(io.out.bits.uop.exceptionVec, StaCfg).asUInt.orR
116
117  io.in.ready := true.B
118
119  io.dtlbResp.ready := true.B // TODO: why dtlbResp needs a ready?
120
121  // st-ld violation dectect request.
122  io.reExecuteQuery.valid := io.in.valid && !s1_tlb_miss
123  io.reExecuteQuery.bits.robIdx := io.in.bits.uop.robIdx
124  io.reExecuteQuery.bits.paddr := s1_paddr
125  io.reExecuteQuery.bits.mask := io.in.bits.mask
126
127  // Send TLB feedback to store issue queue
128  // Store feedback is generated in store_s1, sent to RS in store_s2
129  io.rsFeedback.valid := io.in.valid
130  io.rsFeedback.bits.hit := !s1_tlb_miss
131  io.rsFeedback.bits.flushState := io.dtlbResp.bits.ptwBack
132  io.rsFeedback.bits.rsIdx := io.in.bits.rsIdx
133  io.rsFeedback.bits.sourceType := RSFeedbackType.tlbMiss
134  XSDebug(io.rsFeedback.valid,
135    "S1 Store: tlbHit: %d robIdx: %d\n",
136    io.rsFeedback.bits.hit,
137    io.rsFeedback.bits.rsIdx
138  )
139  io.rsFeedback.bits.dataInvalidSqIdx := DontCare
140
141  // get paddr from dtlb, check if rollback is needed
142  // writeback store inst to lsq
143  io.out.valid := io.in.valid && !s1_tlb_miss
144  io.out.bits := io.in.bits
145  io.out.bits.paddr := s1_paddr
146  io.out.bits.miss := false.B
147  io.out.bits.mmio := s1_mmio
148  io.out.bits.atomic := s1_mmio
149  io.out.bits.uop.exceptionVec(storePageFault) := io.dtlbResp.bits.excp(0).pf.st
150  io.out.bits.uop.exceptionVec(storeAccessFault) := io.dtlbResp.bits.excp(0).af.st
151
152  io.lsq.valid := io.in.valid
153  io.lsq.bits := io.out.bits
154  io.lsq.bits.miss := s1_tlb_miss
155
156  // mmio inst with exception will be writebacked immediately
157  // io.out.valid := io.in.valid && (!io.out.bits.mmio || s1_exception) && !s1_tlb_miss
158
159  XSPerfAccumulate("in_valid", io.in.valid)
160  XSPerfAccumulate("in_fire", io.in.fire)
161  XSPerfAccumulate("in_fire_first_issue", io.in.fire && io.in.bits.isFirstIssue)
162  XSPerfAccumulate("tlb_miss", io.in.fire && s1_tlb_miss)
163  XSPerfAccumulate("tlb_miss_first_issue", io.in.fire && s1_tlb_miss && io.in.bits.isFirstIssue)
164}
165
166class StoreUnit_S2(implicit p: Parameters) extends XSModule {
167  val io = IO(new Bundle() {
168    val in = Flipped(Decoupled(new LsPipelineBundle))
169    val pmpResp = Flipped(new PMPRespBundle)
170    val static_pm = Input(Valid(Bool()))
171    val out = Decoupled(new LsPipelineBundle)
172  })
173  val pmp = WireInit(io.pmpResp)
174  when (io.static_pm.valid) {
175    pmp.ld := false.B
176    pmp.st := false.B
177    pmp.instr := false.B
178    pmp.mmio := io.static_pm.bits
179  }
180
181  val s2_exception = ExceptionNO.selectByFu(io.out.bits.uop.exceptionVec, StaCfg).asUInt.orR
182  val is_mmio = io.in.bits.mmio || pmp.mmio
183
184  io.in.ready := true.B
185  io.out.bits := io.in.bits
186  io.out.bits.mmio := is_mmio && !s2_exception
187  io.out.bits.atomic := io.in.bits.atomic || pmp.atomic
188  io.out.bits.uop.exceptionVec(storeAccessFault) := io.in.bits.uop.exceptionVec(storeAccessFault) || pmp.st
189  io.out.valid := io.in.valid && (!is_mmio || s2_exception)
190}
191
192class StoreUnit_S3(implicit p: Parameters) extends XSModule {
193  val io = IO(new Bundle() {
194    val in = Flipped(Decoupled(new LsPipelineBundle))
195    val stout = DecoupledIO(new MemExuOutput) // writeback store
196  })
197
198  io.in.ready := true.B
199
200  io.stout.valid := io.in.valid
201  io.stout.bits.uop := io.in.bits.uop
202  io.stout.bits.data := DontCare
203  io.stout.bits.debug.isMMIO := io.in.bits.mmio
204  io.stout.bits.debug.paddr := io.in.bits.paddr
205  io.stout.bits.debug.vaddr := io.in.bits.vaddr
206  io.stout.bits.debug.isPerfCnt := false.B
207}
208
209class StoreUnit(implicit p: Parameters) extends XSModule {
210  val io = IO(new Bundle() {
211    val stin = Flipped(Decoupled(new MemExuInput))
212    val redirect = Flipped(ValidIO(new Redirect))
213    val feedbackSlow = ValidIO(new RSFeedback)
214    val tlb = new TlbRequestIO()
215    val pmp = Flipped(new PMPRespBundle())
216    val rsIdx = Input(UInt(log2Up(IssQueSize).W))
217    val isFirstIssue = Input(Bool())
218    val lsq = ValidIO(new LsPipelineBundle)
219    val lsq_replenish = Output(new LsPipelineBundle())
220    val stout = DecoupledIO(new MemExuOutput) // writeback store
221    // store mask, send to sq in store_s0
222    val storeMaskOut = Valid(new StoreMaskBundle)
223    val reExecuteQuery = Valid(new LoadReExecuteQueryIO)
224    val issue = Valid(new MemExuInput)
225  })
226
227  val store_s0 = Module(new StoreUnit_S0)
228  val store_s1 = Module(new StoreUnit_S1)
229  val store_s2 = Module(new StoreUnit_S2)
230  val store_s3 = Module(new StoreUnit_S3)
231
232  store_s0.io.in <> io.stin
233  store_s0.io.dtlbReq <> io.tlb.req
234  io.tlb.req_kill := false.B
235  store_s0.io.rsIdx := io.rsIdx
236  store_s0.io.isFirstIssue := io.isFirstIssue
237
238  io.storeMaskOut.valid := store_s0.io.in.valid
239  io.storeMaskOut.bits.mask := store_s0.io.out.bits.mask
240  io.storeMaskOut.bits.sqIdx := store_s0.io.out.bits.uop.sqIdx
241
242  PipelineConnect(store_s0.io.out, store_s1.io.in, true.B, store_s0.io.out.bits.uop.robIdx.needFlush(io.redirect))
243  io.issue.valid := store_s1.io.in.valid && !store_s1.io.dtlbResp.bits.miss
244  io.issue.bits := RegEnable(store_s0.io.in.bits, store_s0.io.in.valid)
245
246  store_s1.io.dtlbResp <> io.tlb.resp
247  io.lsq <> store_s1.io.lsq
248  io.reExecuteQuery := store_s1.io.reExecuteQuery
249
250  PipelineConnect(store_s1.io.out, store_s2.io.in, true.B, store_s1.io.out.bits.uop.robIdx.needFlush(io.redirect))
251
252  // feedback tlb miss to RS in store_s2
253  io.feedbackSlow.bits := RegNext(store_s1.io.rsFeedback.bits)
254  io.feedbackSlow.valid := RegNext(store_s1.io.rsFeedback.valid && !store_s1.io.out.bits.uop.robIdx.needFlush(io.redirect))
255
256  store_s2.io.pmpResp <> io.pmp
257  store_s2.io.static_pm := RegNext(io.tlb.resp.bits.static_pm)
258  io.lsq_replenish := store_s2.io.out.bits // mmio and exception
259  PipelineConnect(store_s2.io.out, store_s3.io.in, true.B, store_s2.io.out.bits.uop.robIdx.needFlush(io.redirect))
260
261  store_s3.io.stout <> io.stout
262
263  private def printPipeLine(pipeline: LsPipelineBundle, cond: Bool, name: String): Unit = {
264    XSDebug(cond,
265      p"$name" + p" pc ${Hexadecimal(pipeline.uop.pc)} " +
266        p"addr ${Hexadecimal(pipeline.vaddr)} -> ${Hexadecimal(pipeline.paddr)} " +
267        p"op ${Binary(pipeline.uop.fuOpType)} " +
268        p"data ${Hexadecimal(pipeline.data)} " +
269        p"mask ${Hexadecimal(pipeline.mask)}\n"
270    )
271  }
272
273  printPipeLine(store_s0.io.out.bits, store_s0.io.out.valid, "S0")
274  printPipeLine(store_s1.io.out.bits, store_s1.io.out.valid, "S1")
275}
276