xref: /XiangShan/src/main/scala/xiangshan/mem/pipeline/StoreUnit.scala (revision 8a00ff566bcba2487c171ffd13c225a25e8ff441)
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.backend.fu.FuConfig.StaCfg
28import xiangshan.backend.rob.DebugLsInfoBundle
29import xiangshan.cache.mmu.{TlbCmd, TlbReq, TlbRequestIO, TlbResp}
30import xiangshan.backend.Bundles.{MemExuInput, MemExuOutput}
31
32
33// Store Pipeline Stage 0
34// Generate addr, use addr to query DCache and DTLB
35class StoreUnit_S0(implicit p: Parameters) extends XSModule {
36  val io = IO(new Bundle() {
37    val in = Flipped(Decoupled(new MemExuInput))
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.memidx.is_ld := false.B
58  io.dtlbReq.bits.memidx.is_st := true.B
59  io.dtlbReq.bits.memidx.idx := io.in.bits.uop.sqIdx.value
60  io.dtlbReq.bits.debug.robIdx := io.in.bits.uop.robIdx
61  io.dtlbReq.bits.no_translate := false.B
62  io.dtlbReq.bits.debug.pc := io.in.bits.uop.pc
63  io.dtlbReq.bits.debug.isFirstIssue := io.in.bits.isFirstIssue
64
65  io.out.bits := DontCare
66  io.out.bits.vaddr := saddr
67
68  // Now data use its own io
69  // io.out.bits.data := genWdata(io.in.bits.src(1), io.in.bits.uop.ctrl.fuOpType(1,0))
70  io.out.bits.data := io.in.bits.src(1) // FIXME: remove data from pipeline
71  io.out.bits.uop := io.in.bits.uop
72  io.out.bits.miss := DontCare
73  io.out.bits.rsIdx := io.in.bits.iqIdx // guarded by io.in.valid
74  io.out.bits.mask := genWmask(io.out.bits.vaddr, io.in.bits.uop.fuOpType(1,0))
75  io.out.bits.isFirstIssue := io.in.bits.isFirstIssue // guarded by io.in.valid
76  io.out.bits.wlineflag := io.in.bits.uop.fuOpType === LSUOpType.cbo_zero
77  io.out.valid := io.in.valid
78  io.in.ready := io.out.ready
79  when(io.in.valid && io.in.bits.isFirstIssue) {
80    io.out.bits.uop.debugInfo.tlbFirstReqTime := GTimer()
81  }
82
83  // exception check
84  val addrAligned = LookupTree(io.in.bits.uop.fuOpType(1,0), List(
85    "b00".U   -> true.B,              //b
86    "b01".U   -> (io.out.bits.vaddr(0) === 0.U),   //h
87    "b10".U   -> (io.out.bits.vaddr(1,0) === 0.U), //w
88    "b11".U   -> (io.out.bits.vaddr(2,0) === 0.U)  //d
89  ))
90
91  io.out.bits.uop.exceptionVec(storeAddrMisaligned) := !addrAligned
92
93  XSPerfAccumulate("in_valid", io.in.valid)
94  XSPerfAccumulate("in_fire", io.in.fire)
95  XSPerfAccumulate("in_fire_first_issue", io.in.fire && io.in.bits.isFirstIssue)
96  XSPerfAccumulate("addr_spec_success", io.out.fire() && saddr(VAddrBits-1, 12) === io.in.bits.src(0)(VAddrBits-1, 12))
97  XSPerfAccumulate("addr_spec_failed", io.out.fire() && saddr(VAddrBits-1, 12) =/= io.in.bits.src(0)(VAddrBits-1, 12))
98  XSPerfAccumulate("addr_spec_success_once", io.out.fire() && saddr(VAddrBits-1, 12) === io.in.bits.src(0)(VAddrBits-1, 12) && io.in.bits.isFirstIssue)
99  XSPerfAccumulate("addr_spec_failed_once", io.out.fire() && saddr(VAddrBits-1, 12) =/= io.in.bits.src(0)(VAddrBits-1, 12) && io.in.bits.isFirstIssue)
100}
101
102// Store Pipeline Stage 1
103// TLB resp (send paddr to dcache)
104class StoreUnit_S1(implicit p: Parameters) extends XSModule {
105  val io = IO(new Bundle() {
106    val in = Flipped(Decoupled(new LsPipelineBundle))
107    val out = Decoupled(new LsPipelineBundle)
108    val lsq = ValidIO(new LsPipelineBundle())
109    val dtlbResp = Flipped(DecoupledIO(new TlbResp()))
110    val rsFeedback = ValidIO(new RSFeedback)
111    val reExecuteQuery = Valid(new LoadReExecuteQueryIO)
112  })
113
114  // mmio cbo decoder
115  val is_mmio_cbo = io.in.bits.uop.fuOpType === LSUOpType.cbo_clean ||
116    io.in.bits.uop.fuOpType === LSUOpType.cbo_flush ||
117    io.in.bits.uop.fuOpType === LSUOpType.cbo_inval
118
119  val s1_paddr = io.dtlbResp.bits.paddr(0)
120  val s1_tlb_miss = io.dtlbResp.bits.miss
121
122  val s1_mmio = is_mmio_cbo
123  val s1_exception = ExceptionNO.selectByFu(io.out.bits.uop.exceptionVec, StaCfg).asUInt.orR
124
125  io.in.ready := true.B
126
127  io.dtlbResp.ready := true.B // TODO: why dtlbResp needs a ready?
128
129  // st-ld violation dectect request.
130  io.reExecuteQuery.valid := io.in.valid && !s1_tlb_miss
131  io.reExecuteQuery.bits.robIdx := io.in.bits.uop.robIdx
132  io.reExecuteQuery.bits.paddr := s1_paddr
133  io.reExecuteQuery.bits.mask := io.in.bits.mask
134
135  // Send TLB feedback to store issue queue
136  // Store feedback is generated in store_s1, sent to RS in store_s2
137  io.rsFeedback.valid := io.in.valid
138  io.rsFeedback.bits.hit := !s1_tlb_miss
139  io.rsFeedback.bits.flushState := io.dtlbResp.bits.ptwBack
140  io.rsFeedback.bits.rsIdx := io.in.bits.rsIdx
141  io.rsFeedback.bits.sourceType := RSFeedbackType.tlbMiss
142  XSDebug(io.rsFeedback.valid,
143    "S1 Store: tlbHit: %d robIdx: %d\n",
144    io.rsFeedback.bits.hit,
145    io.rsFeedback.bits.rsIdx
146  )
147  io.rsFeedback.bits.dataInvalidSqIdx := DontCare
148
149  // get paddr from dtlb, check if rollback is needed
150  // writeback store inst to lsq
151  io.out.valid := io.in.valid && !s1_tlb_miss
152  io.out.bits := io.in.bits
153  io.out.bits.paddr := s1_paddr
154  io.out.bits.miss := false.B
155  io.out.bits.mmio := s1_mmio
156  io.out.bits.atomic := s1_mmio
157  io.out.bits.uop.exceptionVec(storePageFault) := io.dtlbResp.bits.excp(0).pf.st
158  io.out.bits.uop.exceptionVec(storeAccessFault) := io.dtlbResp.bits.excp(0).af.st
159
160  io.lsq.valid := io.in.valid
161  io.lsq.bits := io.out.bits
162  io.lsq.bits.miss := s1_tlb_miss
163
164  // mmio inst with exception will be writebacked immediately
165  // io.out.valid := io.in.valid && (!io.out.bits.mmio || s1_exception) && !s1_tlb_miss
166
167  // write below io.out.bits assign sentence to prevent overwriting values
168  val s1_tlb_memidx = io.dtlbResp.bits.memidx
169  when(s1_tlb_memidx.is_st && io.dtlbResp.valid && !s1_tlb_miss && s1_tlb_memidx.idx === io.out.bits.uop.sqIdx.value) {
170    // printf("Store idx = %d\n", s1_tlb_memidx.idx)
171    io.out.bits.uop.debugInfo.tlbRespTime := GTimer()
172  }
173
174  XSPerfAccumulate("in_valid", io.in.valid)
175  XSPerfAccumulate("in_fire", io.in.fire)
176  XSPerfAccumulate("in_fire_first_issue", io.in.fire && io.in.bits.isFirstIssue)
177  XSPerfAccumulate("tlb_miss", io.in.fire && s1_tlb_miss)
178  XSPerfAccumulate("tlb_miss_first_issue", io.in.fire && s1_tlb_miss && io.in.bits.isFirstIssue)
179}
180
181class StoreUnit_S2(implicit p: Parameters) extends XSModule {
182  val io = IO(new Bundle() {
183    val in = Flipped(Decoupled(new LsPipelineBundle))
184    val pmpResp = Flipped(new PMPRespBundle)
185    val static_pm = Input(Valid(Bool()))
186    val out = Decoupled(new LsPipelineBundle)
187  })
188  val pmp = WireInit(io.pmpResp)
189  when (io.static_pm.valid) {
190    pmp.ld := false.B
191    pmp.st := false.B
192    pmp.instr := false.B
193    pmp.mmio := io.static_pm.bits
194  }
195
196  val s2_exception = ExceptionNO.selectByFu(io.out.bits.uop.exceptionVec, StaCfg).asUInt.orR
197  val is_mmio = io.in.bits.mmio || pmp.mmio
198
199  io.in.ready := true.B
200  io.out.bits := io.in.bits
201  io.out.bits.mmio := is_mmio && !s2_exception
202  io.out.bits.atomic := io.in.bits.atomic || pmp.atomic
203  io.out.bits.uop.exceptionVec(storeAccessFault) := io.in.bits.uop.exceptionVec(storeAccessFault) || pmp.st
204  io.out.valid := io.in.valid && (!is_mmio || s2_exception)
205}
206
207class StoreUnit_S3(implicit p: Parameters) extends XSModule {
208  val io = IO(new Bundle() {
209    val in = Flipped(Decoupled(new LsPipelineBundle))
210    val stout = DecoupledIO(new MemExuOutput) // writeback store
211  })
212
213  io.in.ready := true.B
214
215  io.stout.valid := io.in.valid
216  io.stout.bits.uop := io.in.bits.uop
217  io.stout.bits.data := DontCare
218  io.stout.bits.debug.isMMIO := io.in.bits.mmio
219  io.stout.bits.debug.paddr := io.in.bits.paddr
220  io.stout.bits.debug.vaddr := io.in.bits.vaddr
221  io.stout.bits.debug.isPerfCnt := false.B
222}
223
224class StoreUnit(implicit p: Parameters) extends XSModule {
225  val io = IO(new Bundle() {
226    val stin = Flipped(Decoupled(new MemExuInput))
227    val redirect = Flipped(ValidIO(new Redirect))
228    val feedbackSlow = ValidIO(new RSFeedback)
229    val tlb = new TlbRequestIO()
230    val pmp = Flipped(new PMPRespBundle())
231    val lsq = ValidIO(new LsPipelineBundle)
232    val lsq_replenish = Output(new LsPipelineBundle())
233    val stout = DecoupledIO(new MemExuOutput) // writeback store
234    // store mask, send to sq in store_s0
235    val storeMaskOut = Valid(new StoreMaskBundle)
236    val reExecuteQuery = Valid(new LoadReExecuteQueryIO)
237    val issue = Valid(new MemExuInput)
238    val debug_ls = Output(new DebugLsInfoBundle)
239  })
240
241  val store_s0 = Module(new StoreUnit_S0)
242  val store_s1 = Module(new StoreUnit_S1)
243  val store_s2 = Module(new StoreUnit_S2)
244  val store_s3 = Module(new StoreUnit_S3)
245
246  store_s0.io.in <> io.stin
247  store_s0.io.dtlbReq <> io.tlb.req
248  io.tlb.req_kill := false.B
249
250  io.storeMaskOut.valid := store_s0.io.in.valid
251  io.storeMaskOut.bits.mask := store_s0.io.out.bits.mask
252  io.storeMaskOut.bits.sqIdx := store_s0.io.out.bits.uop.sqIdx
253
254  PipelineConnect(store_s0.io.out, store_s1.io.in, true.B, store_s0.io.out.bits.uop.robIdx.needFlush(io.redirect))
255  io.issue.valid := store_s1.io.in.valid && !store_s1.io.dtlbResp.bits.miss
256  io.issue.bits := RegEnable(store_s0.io.in.bits, store_s0.io.in.valid)
257
258  store_s1.io.dtlbResp <> io.tlb.resp
259  io.lsq <> store_s1.io.lsq
260  io.reExecuteQuery := store_s1.io.reExecuteQuery
261
262  PipelineConnect(store_s1.io.out, store_s2.io.in, true.B, store_s1.io.out.bits.uop.robIdx.needFlush(io.redirect))
263
264  // feedback tlb miss to RS in store_s2
265  io.feedbackSlow.bits := RegNext(store_s1.io.rsFeedback.bits)
266  io.feedbackSlow.valid := RegNext(store_s1.io.rsFeedback.valid && !store_s1.io.out.bits.uop.robIdx.needFlush(io.redirect))
267
268  store_s2.io.pmpResp <> io.pmp
269  store_s2.io.static_pm := RegNext(io.tlb.resp.bits.static_pm)
270  io.lsq_replenish := store_s2.io.out.bits // mmio and exception
271  PipelineConnect(store_s2.io.out, store_s3.io.in, true.B, store_s2.io.out.bits.uop.robIdx.needFlush(io.redirect))
272
273  store_s3.io.stout <> io.stout
274
275  io.debug_ls := DontCare
276  io.debug_ls.s1.isTlbFirstMiss := io.tlb.resp.valid && io.tlb.resp.bits.miss && io.tlb.resp.bits.debug.isFirstIssue
277  io.debug_ls.s1_robIdx := store_s1.io.in.bits.uop.robIdx.value
278
279  private def printPipeLine(pipeline: LsPipelineBundle, cond: Bool, name: String): Unit = {
280    XSDebug(cond,
281      p"$name" + p" pc ${Hexadecimal(pipeline.uop.pc)} " +
282        p"addr ${Hexadecimal(pipeline.vaddr)} -> ${Hexadecimal(pipeline.paddr)} " +
283        p"op ${Binary(pipeline.uop.fuOpType)} " +
284        p"data ${Hexadecimal(pipeline.data)} " +
285        p"mask ${Hexadecimal(pipeline.mask)}\n"
286    )
287  }
288
289  printPipeLine(store_s0.io.out.bits, store_s0.io.out.valid, "S0")
290  printPipeLine(store_s1.io.out.bits, store_s1.io.out.valid, "S1")
291}
292