xref: /XiangShan/src/main/scala/xiangshan/mem/pipeline/StoreUnit.scala (revision deb6421e9ab9b7980dc6c429456fc7bd2161357b)
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 xiangshan.ExceptionNO._
24import xiangshan._
25import xiangshan.backend.fu.PMPRespBundle
26import xiangshan.cache.mmu.{TlbCmd, TlbReq, TlbRequestIO, TlbResp}
27
28// Store Pipeline Stage 0
29// Generate addr, use addr to query DCache and DTLB
30class StoreUnit_S0(implicit p: Parameters) extends XSModule {
31  val io = IO(new Bundle() {
32    val in = Flipped(Decoupled(new ExuInput))
33    val rsIdx = Input(UInt(log2Up(IssQueSize).W))
34    val isFirstIssue = Input(Bool())
35    val out = Decoupled(new LsPipelineBundle)
36    val dtlbReq = DecoupledIO(new TlbReq)
37  })
38
39  // send req to dtlb
40  // val saddr = io.in.bits.src(0) + SignExt(io.in.bits.uop.ctrl.imm(11,0), VAddrBits)
41  val imm12 = WireInit(io.in.bits.uop.ctrl.imm(11,0))
42  val saddr_lo = io.in.bits.src(0)(11,0) + Cat(0.U(1.W), imm12)
43  val saddr_hi = Mux(saddr_lo(12),
44    Mux(imm12(11), io.in.bits.src(0)(VAddrBits-1, 12), io.in.bits.src(0)(VAddrBits-1, 12)+1.U),
45    Mux(imm12(11), io.in.bits.src(0)(VAddrBits-1, 12)+SignExt(1.U, VAddrBits-12), io.in.bits.src(0)(VAddrBits-1, 12)),
46  )
47  val saddr = Cat(saddr_hi, saddr_lo(11,0))
48
49  io.dtlbReq.bits.vaddr := saddr
50  io.dtlbReq.valid := io.in.valid
51  io.dtlbReq.bits.cmd := TlbCmd.write
52  io.dtlbReq.bits.size := LSUOpType.size(io.in.bits.uop.ctrl.fuOpType)
53  io.dtlbReq.bits.kill := DontCare
54  io.dtlbReq.bits.debug.robIdx := io.in.bits.uop.robIdx
55  io.dtlbReq.bits.debug.pc := io.in.bits.uop.cf.pc
56  io.dtlbReq.bits.debug.isFirstIssue := io.isFirstIssue
57
58  io.out.bits := DontCare
59  io.out.bits.vaddr := saddr
60
61  // Now data use its own io
62  // io.out.bits.data := genWdata(io.in.bits.src(1), io.in.bits.uop.ctrl.fuOpType(1,0))
63  io.out.bits.data := io.in.bits.src(1) // FIXME: remove data from pipeline
64  io.out.bits.uop := io.in.bits.uop
65  io.out.bits.miss := DontCare
66  io.out.bits.rsIdx := io.rsIdx
67  io.out.bits.mask := genWmask(io.out.bits.vaddr, io.in.bits.uop.ctrl.fuOpType(1,0))
68  io.out.bits.isFirstIssue := io.isFirstIssue
69  io.out.bits.wlineflag := io.in.bits.uop.ctrl.fuOpType === LSUOpType.cbo_zero
70  io.out.valid := io.in.valid
71  io.in.ready := io.out.ready
72
73  // exception check
74  val addrAligned = LookupTree(io.in.bits.uop.ctrl.fuOpType(1,0), List(
75    "b00".U   -> true.B,              //b
76    "b01".U   -> (io.out.bits.vaddr(0) === 0.U),   //h
77    "b10".U   -> (io.out.bits.vaddr(1,0) === 0.U), //w
78    "b11".U   -> (io.out.bits.vaddr(2,0) === 0.U)  //d
79  ))
80
81  io.out.bits.uop.cf.exceptionVec(storeAddrMisaligned) := !addrAligned
82
83  XSPerfAccumulate("in_valid", io.in.valid)
84  XSPerfAccumulate("in_fire", io.in.fire)
85  XSPerfAccumulate("in_fire_first_issue", io.in.fire && io.isFirstIssue)
86  XSPerfAccumulate("addr_spec_success", io.out.fire() && saddr(VAddrBits-1, 12) === io.in.bits.src(0)(VAddrBits-1, 12))
87  XSPerfAccumulate("addr_spec_failed", io.out.fire() && saddr(VAddrBits-1, 12) =/= io.in.bits.src(0)(VAddrBits-1, 12))
88  XSPerfAccumulate("addr_spec_success_once", io.out.fire() && saddr(VAddrBits-1, 12) === io.in.bits.src(0)(VAddrBits-1, 12) && io.isFirstIssue)
89  XSPerfAccumulate("addr_spec_failed_once", io.out.fire() && saddr(VAddrBits-1, 12) =/= io.in.bits.src(0)(VAddrBits-1, 12) && io.isFirstIssue)
90}
91
92// Store Pipeline Stage 1
93// TLB resp (send paddr to dcache)
94class StoreUnit_S1(implicit p: Parameters) extends XSModule {
95  val io = IO(new Bundle() {
96    val in = Flipped(Decoupled(new LsPipelineBundle))
97    val out = Decoupled(new LsPipelineBundle)
98    val lsq = ValidIO(new LsPipelineBundle())
99    val dtlbResp = Flipped(DecoupledIO(new TlbResp()))
100    val rsFeedback = ValidIO(new RSFeedback)
101    val reExecuteQuery = Valid(new LoadReExecuteQueryIO)
102  })
103
104  // mmio cbo decoder
105  val is_mmio_cbo = io.in.bits.uop.ctrl.fuOpType === LSUOpType.cbo_clean ||
106    io.in.bits.uop.ctrl.fuOpType === LSUOpType.cbo_flush ||
107    io.in.bits.uop.ctrl.fuOpType === LSUOpType.cbo_inval
108
109  val s1_paddr = io.dtlbResp.bits.paddr(0)
110  val s1_tlb_miss = io.dtlbResp.bits.miss
111  val s1_mmio = is_mmio_cbo
112  val s1_exception = ExceptionNO.selectByFu(io.out.bits.uop.cf.exceptionVec, staCfg).asUInt.orR
113
114  io.in.ready := true.B
115
116  io.dtlbResp.ready := true.B // TODO: why dtlbResp needs a ready?
117
118  // st-ld violation dectect request.
119  io.reExecuteQuery.valid := io.in.valid && !s1_tlb_miss
120  io.reExecuteQuery.bits.robIdx := io.in.bits.uop.robIdx
121  io.reExecuteQuery.bits.paddr := s1_paddr
122  io.reExecuteQuery.bits.mask := io.in.bits.mask
123
124  // Send TLB feedback to store issue queue
125  // Store feedback is generated in store_s1, sent to RS in store_s2
126  io.rsFeedback.valid := io.in.valid
127  io.rsFeedback.bits.hit := !s1_tlb_miss
128  io.rsFeedback.bits.flushState := io.dtlbResp.bits.ptwBack
129  io.rsFeedback.bits.rsIdx := io.in.bits.rsIdx
130  io.rsFeedback.bits.sourceType := RSFeedbackType.tlbMiss
131  XSDebug(io.rsFeedback.valid,
132    "S1 Store: tlbHit: %d robIdx: %d\n",
133    io.rsFeedback.bits.hit,
134    io.rsFeedback.bits.rsIdx
135  )
136  io.rsFeedback.bits.dataInvalidSqIdx := DontCare
137
138  // get paddr from dtlb, check if rollback is needed
139  // writeback store inst to lsq
140  io.out.valid := io.in.valid && !s1_tlb_miss
141  io.out.bits := io.in.bits
142  io.out.bits.paddr := s1_paddr
143  io.out.bits.miss := false.B
144  io.out.bits.mmio := s1_mmio
145  io.out.bits.atomic := s1_mmio
146  io.out.bits.uop.cf.exceptionVec(storePageFault) := io.dtlbResp.bits.excp(0).pf.st
147  io.out.bits.uop.cf.exceptionVec(storeAccessFault) := io.dtlbResp.bits.excp(0).af.st
148
149  io.lsq.valid := io.in.valid
150  io.lsq.bits := io.out.bits
151  io.lsq.bits.miss := s1_tlb_miss
152
153  // mmio inst with exception will be writebacked immediately
154  // io.out.valid := io.in.valid && (!io.out.bits.mmio || s1_exception) && !s1_tlb_miss
155
156  XSPerfAccumulate("in_valid", io.in.valid)
157  XSPerfAccumulate("in_fire", io.in.fire)
158  XSPerfAccumulate("in_fire_first_issue", io.in.fire && io.in.bits.isFirstIssue)
159  XSPerfAccumulate("tlb_miss", io.in.fire && s1_tlb_miss)
160  XSPerfAccumulate("tlb_miss_first_issue", io.in.fire && s1_tlb_miss && io.in.bits.isFirstIssue)
161}
162
163class StoreUnit_S2(implicit p: Parameters) extends XSModule {
164  val io = IO(new Bundle() {
165    val in = Flipped(Decoupled(new LsPipelineBundle))
166    val pmpResp = Flipped(new PMPRespBundle)
167    val static_pm = Input(Valid(Bool()))
168    val out = Decoupled(new LsPipelineBundle)
169  })
170  val pmp = WireInit(io.pmpResp)
171  when (io.static_pm.valid) {
172    pmp.ld := false.B
173    pmp.st := false.B
174    pmp.instr := false.B
175    pmp.mmio := io.static_pm.bits
176  }
177
178  val s2_exception = ExceptionNO.selectByFu(io.out.bits.uop.cf.exceptionVec, staCfg).asUInt.orR
179  val is_mmio = io.in.bits.mmio || pmp.mmio
180
181  io.in.ready := true.B
182  io.out.bits := io.in.bits
183  io.out.bits.mmio := is_mmio && !s2_exception
184  io.out.bits.atomic := io.in.bits.atomic || pmp.atomic
185  io.out.bits.uop.cf.exceptionVec(storeAccessFault) := io.in.bits.uop.cf.exceptionVec(storeAccessFault) || pmp.st
186  io.out.valid := io.in.valid && (!is_mmio || s2_exception)
187}
188
189class StoreUnit_S3(implicit p: Parameters) extends XSModule {
190  val io = IO(new Bundle() {
191    val in = Flipped(Decoupled(new LsPipelineBundle))
192    val stout = DecoupledIO(new ExuOutput) // writeback store
193  })
194
195  io.in.ready := true.B
196
197  io.stout.valid := io.in.valid
198  io.stout.bits.uop := io.in.bits.uop
199  io.stout.bits.data := DontCare
200  io.stout.bits.redirectValid := false.B
201  io.stout.bits.redirect := DontCare
202  io.stout.bits.debug.isMMIO := io.in.bits.mmio
203  io.stout.bits.debug.paddr := io.in.bits.paddr
204  io.stout.bits.debug.vaddr := io.in.bits.vaddr
205  io.stout.bits.debug.isPerfCnt := false.B
206  io.stout.bits.fflags := DontCare
207
208}
209
210class StoreUnit(implicit p: Parameters) extends XSModule {
211  val io = IO(new Bundle() {
212    val stin = Flipped(Decoupled(new ExuInput))
213    val redirect = Flipped(ValidIO(new Redirect))
214    val feedbackSlow = ValidIO(new RSFeedback)
215    val tlb = new TlbRequestIO()
216    val pmp = Flipped(new PMPRespBundle())
217    val rsIdx = Input(UInt(log2Up(IssQueSize).W))
218    val isFirstIssue = Input(Bool())
219    val lsq = ValidIO(new LsPipelineBundle)
220    val lsq_replenish = Output(new LsPipelineBundle())
221    val stout = DecoupledIO(new ExuOutput) // writeback store
222    // store mask, send to sq in store_s0
223    val storeMaskOut = Valid(new StoreMaskBundle)
224    val reExecuteQuery = Valid(new LoadReExecuteQueryIO)
225    val issue = Valid(new ExuInput)
226  })
227
228  val store_s0 = Module(new StoreUnit_S0)
229  val store_s1 = Module(new StoreUnit_S1)
230  val store_s2 = Module(new StoreUnit_S2)
231  val store_s3 = Module(new StoreUnit_S3)
232
233  store_s0.io.in <> io.stin
234  store_s0.io.dtlbReq <> io.tlb.req
235  io.tlb.req_kill := false.B
236  store_s0.io.rsIdx := io.rsIdx
237  store_s0.io.isFirstIssue := io.isFirstIssue
238
239  io.storeMaskOut.valid := store_s0.io.in.valid
240  io.storeMaskOut.bits.mask := store_s0.io.out.bits.mask
241  io.storeMaskOut.bits.sqIdx := store_s0.io.out.bits.uop.sqIdx
242
243  PipelineConnect(store_s0.io.out, store_s1.io.in, true.B, store_s0.io.out.bits.uop.robIdx.needFlush(io.redirect))
244  io.issue.valid := store_s1.io.in.valid && !store_s1.io.dtlbResp.bits.miss
245  io.issue.bits := RegEnable(store_s0.io.in.bits, store_s0.io.in.valid)
246
247  store_s1.io.dtlbResp <> io.tlb.resp
248  io.lsq <> store_s1.io.lsq
249  io.reExecuteQuery := store_s1.io.reExecuteQuery
250
251  PipelineConnect(store_s1.io.out, store_s2.io.in, true.B, store_s1.io.out.bits.uop.robIdx.needFlush(io.redirect))
252
253  // feedback tlb miss to RS in store_s2
254  io.feedbackSlow.bits := RegNext(store_s1.io.rsFeedback.bits)
255  io.feedbackSlow.valid := RegNext(store_s1.io.rsFeedback.valid && !store_s1.io.out.bits.uop.robIdx.needFlush(io.redirect))
256
257  store_s2.io.pmpResp <> io.pmp
258  store_s2.io.static_pm := RegNext(io.tlb.resp.bits.static_pm)
259  io.lsq_replenish := store_s2.io.out.bits // mmio and exception
260  PipelineConnect(store_s2.io.out, store_s3.io.in, true.B, store_s2.io.out.bits.uop.robIdx.needFlush(io.redirect))
261
262  store_s3.io.stout <> io.stout
263
264  private def printPipeLine(pipeline: LsPipelineBundle, cond: Bool, name: String): Unit = {
265    XSDebug(cond,
266      p"$name" + p" pc ${Hexadecimal(pipeline.uop.cf.pc)} " +
267        p"addr ${Hexadecimal(pipeline.vaddr)} -> ${Hexadecimal(pipeline.paddr)} " +
268        p"op ${Binary(pipeline.uop.ctrl.fuOpType)} " +
269        p"data ${Hexadecimal(pipeline.data)} " +
270        p"mask ${Hexadecimal(pipeline.mask)}\n"
271    )
272  }
273
274  printPipeLine(store_s0.io.out.bits, store_s0.io.out.valid, "S0")
275  printPipeLine(store_s1.io.out.bits, store_s1.io.out.valid, "S1")
276}
277