xref: /XiangShan/src/main/scala/xiangshan/mem/pipeline/StoreUnit.scala (revision af2f784960342aa80738a7ef865530f2b2e215d0)
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._
24import xiangshan.backend.decode.ImmUnion
25import xiangshan.backend.fu.PMPRespBundle
26import xiangshan.cache._
27import xiangshan.cache.mmu.{TLB, TlbCmd, TlbPtwIO, TlbReq, TlbRequestIO, TlbResp}
28
29// Store Pipeline Stage 0
30// Generate addr, use addr to query DCache and DTLB
31class StoreUnit_S0(implicit p: Parameters) extends XSModule {
32  val io = IO(new Bundle() {
33    val in = Flipped(Decoupled(new ExuInput))
34    val rsIdx = Input(UInt(log2Up(IssQueSize).W))
35    val isFirstIssue = Input(Bool())
36    val out = Decoupled(new LsPipelineBundle)
37    val dtlbReq = DecoupledIO(new TlbReq)
38  })
39
40  // send req to dtlb
41  // val saddr = io.in.bits.src(0) + SignExt(io.in.bits.uop.ctrl.imm(11,0), VAddrBits)
42  val imm12 = WireInit(io.in.bits.uop.ctrl.imm(11,0))
43  val saddr_lo = io.in.bits.src(0)(11,0) + Cat(0.U(1.W), imm12)
44  val saddr_hi = Mux(saddr_lo(12),
45    Mux(imm12(11), io.in.bits.src(0)(VAddrBits-1, 12), io.in.bits.src(0)(VAddrBits-1, 12)+1.U),
46    Mux(imm12(11), io.in.bits.src(0)(VAddrBits-1, 12)+SignExt(1.U, VAddrBits-12), io.in.bits.src(0)(VAddrBits-1, 12)),
47  )
48  val saddr = Cat(saddr_hi, saddr_lo(11,0))
49
50  io.dtlbReq.bits.vaddr := saddr
51  io.dtlbReq.valid := io.in.valid
52  io.dtlbReq.bits.cmd := TlbCmd.write
53  io.dtlbReq.bits.size := LSUOpType.size(io.in.bits.uop.ctrl.fuOpType)
54  io.dtlbReq.bits.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  io.out.bits.uop.cf.exceptionVec(storeAddrMisaligned) := !addrAligned
81
82  XSPerfAccumulate("in_valid", io.in.valid)
83  XSPerfAccumulate("in_fire", io.in.fire)
84  XSPerfAccumulate("in_fire_first_issue", io.in.fire && io.isFirstIssue)
85  XSPerfAccumulate("addr_spec_success", io.out.fire() && saddr(VAddrBits-1, 12) === io.in.bits.src(0)(VAddrBits-1, 12))
86  XSPerfAccumulate("addr_spec_failed", io.out.fire() && saddr(VAddrBits-1, 12) =/= io.in.bits.src(0)(VAddrBits-1, 12))
87  XSPerfAccumulate("addr_spec_success_once", io.out.fire() && saddr(VAddrBits-1, 12) === io.in.bits.src(0)(VAddrBits-1, 12) && io.isFirstIssue)
88  XSPerfAccumulate("addr_spec_failed_once", io.out.fire() && saddr(VAddrBits-1, 12) =/= io.in.bits.src(0)(VAddrBits-1, 12) && io.isFirstIssue)
89}
90
91// Store Pipeline Stage 1
92// TLB resp (send paddr to dcache)
93class StoreUnit_S1(implicit p: Parameters) extends XSModule {
94  val io = IO(new Bundle() {
95    val in = Flipped(Decoupled(new LsPipelineBundle))
96    val out = Decoupled(new LsPipelineBundle)
97    val dtlbResp = Flipped(DecoupledIO(new TlbResp))
98    val rsFeedback = ValidIO(new RSFeedback)
99  })
100
101  // mmio cbo decoder
102  val is_mmio_cbo = io.in.bits.uop.ctrl.fuOpType === LSUOpType.cbo_clean ||
103    io.in.bits.uop.ctrl.fuOpType === LSUOpType.cbo_flush ||
104    io.in.bits.uop.ctrl.fuOpType === LSUOpType.cbo_inval
105
106  val s1_paddr = io.dtlbResp.bits.paddr
107  val s1_tlb_miss = io.dtlbResp.bits.miss
108  val s1_mmio = is_mmio_cbo
109  val s1_exception = selectStore(io.out.bits.uop.cf.exceptionVec, false).asUInt.orR
110
111  io.in.ready := true.B
112
113  io.dtlbResp.ready := true.B // TODO: why dtlbResp needs a ready?
114
115  // Send TLB feedback to store issue queue
116  io.rsFeedback.valid := io.in.valid
117  io.rsFeedback.bits.hit := !s1_tlb_miss
118  io.rsFeedback.bits.flushState := io.dtlbResp.bits.ptwBack
119  io.rsFeedback.bits.rsIdx := io.in.bits.rsIdx
120  io.rsFeedback.bits.sourceType := RSFeedbackType.tlbMiss
121  XSDebug(io.rsFeedback.valid,
122    "S1 Store: tlbHit: %d robIdx: %d\n",
123    io.rsFeedback.bits.hit,
124    io.rsFeedback.bits.rsIdx
125  )
126  io.rsFeedback.bits.dataInvalidSqIdx := DontCare
127
128  // get paddr from dtlb, check if rollback is needed
129  // writeback store inst to lsq
130  io.out.valid := io.in.valid && !s1_tlb_miss
131  io.out.bits := io.in.bits
132  io.out.bits.paddr := s1_paddr
133  io.out.bits.miss := false.B
134  io.out.bits.mmio := s1_mmio
135  io.out.bits.uop.cf.exceptionVec(storePageFault) := io.dtlbResp.bits.excp.pf.st
136  io.out.bits.uop.cf.exceptionVec(storeAccessFault) := io.dtlbResp.bits.excp.af.st
137
138  // mmio inst with exception will be writebacked immediately
139  // io.out.valid := io.in.valid && (!io.out.bits.mmio || s1_exception) && !s1_tlb_miss
140
141  XSPerfAccumulate("in_valid", io.in.valid)
142  XSPerfAccumulate("in_fire", io.in.fire)
143  XSPerfAccumulate("in_fire_first_issue", io.in.fire && io.in.bits.isFirstIssue)
144  XSPerfAccumulate("tlb_miss", io.in.fire && s1_tlb_miss)
145  XSPerfAccumulate("tlb_miss_first_issue", io.in.fire && s1_tlb_miss && io.in.bits.isFirstIssue)
146}
147
148class StoreUnit_S2(implicit p: Parameters) extends XSModule {
149  val io = IO(new Bundle() {
150    val in = Flipped(Decoupled(new LsPipelineBundle))
151    val pmpResp = Flipped(new PMPRespBundle)
152    val out = Decoupled(new LsPipelineBundle)
153  })
154
155  val s2_exception = selectStore(io.out.bits.uop.cf.exceptionVec, false).asUInt.orR
156
157  io.in.ready := true.B
158  io.out.bits := io.in.bits
159  io.out.bits.mmio := (io.in.bits.mmio || io.pmpResp.mmio) && !s2_exception
160  io.out.bits.uop.cf.exceptionVec(storeAccessFault) := io.in.bits.uop.cf.exceptionVec(storeAccessFault) || io.pmpResp.st
161  io.out.valid := io.in.valid && (!io.out.bits.mmio || s2_exception)
162}
163
164class StoreUnit_S3(implicit p: Parameters) extends XSModule {
165  val io = IO(new Bundle() {
166    val in = Flipped(Decoupled(new LsPipelineBundle))
167    val stout = DecoupledIO(new ExuOutput) // writeback store
168  })
169
170  io.in.ready := true.B
171
172  io.stout.valid := io.in.valid
173  io.stout.bits.uop := io.in.bits.uop
174  io.stout.bits.data := DontCare
175  io.stout.bits.redirectValid := false.B
176  io.stout.bits.redirect := DontCare
177  io.stout.bits.debug.isMMIO := io.in.bits.mmio
178  io.stout.bits.debug.paddr := DontCare
179  io.stout.bits.debug.isPerfCnt := false.B
180  io.stout.bits.fflags := DontCare
181
182}
183
184class StoreUnit(implicit p: Parameters) extends XSModule {
185  val io = IO(new Bundle() {
186    val stin = Flipped(Decoupled(new ExuInput))
187    val redirect = Flipped(ValidIO(new Redirect))
188    val feedbackSlow = ValidIO(new RSFeedback)
189    val tlb = new TlbRequestIO()
190    val pmp = Flipped(new PMPRespBundle())
191    val rsIdx = Input(UInt(log2Up(IssQueSize).W))
192    val isFirstIssue = Input(Bool())
193    val lsq = ValidIO(new LsPipelineBundle)
194    val lsq_replenish = Output(new LsPipelineBundle())
195    val stout = DecoupledIO(new ExuOutput) // writeback store
196  })
197
198  val store_s0 = Module(new StoreUnit_S0)
199  val store_s1 = Module(new StoreUnit_S1)
200  val store_s2 = Module(new StoreUnit_S2)
201  val store_s3 = Module(new StoreUnit_S3)
202
203  store_s0.io.in <> io.stin
204  store_s0.io.dtlbReq <> io.tlb.req
205  store_s0.io.rsIdx := io.rsIdx
206  store_s0.io.isFirstIssue := io.isFirstIssue
207
208  PipelineConnect(store_s0.io.out, store_s1.io.in, true.B, store_s0.io.out.bits.uop.robIdx.needFlush(io.redirect))
209
210
211  store_s1.io.dtlbResp <> io.tlb.resp
212  store_s1.io.rsFeedback <> io.feedbackSlow
213  io.lsq.bits := store_s1.io.out.bits
214  io.lsq.valid := store_s1.io.out.valid
215
216  PipelineConnect(store_s1.io.out, store_s2.io.in, true.B, store_s1.io.out.bits.uop.robIdx.needFlush(io.redirect))
217
218  store_s2.io.pmpResp <> io.pmp
219  io.lsq_replenish := store_s2.io.out.bits // mmio and exception
220  PipelineConnect(store_s2.io.out, store_s3.io.in, true.B, store_s2.io.out.bits.uop.robIdx.needFlush(io.redirect))
221
222  store_s3.io.stout <> io.stout
223
224  private def printPipeLine(pipeline: LsPipelineBundle, cond: Bool, name: String): Unit = {
225    XSDebug(cond,
226      p"$name" + p" pc ${Hexadecimal(pipeline.uop.cf.pc)} " +
227        p"addr ${Hexadecimal(pipeline.vaddr)} -> ${Hexadecimal(pipeline.paddr)} " +
228        p"op ${Binary(pipeline.uop.ctrl.fuOpType)} " +
229        p"data ${Hexadecimal(pipeline.data)} " +
230        p"mask ${Hexadecimal(pipeline.mask)}\n"
231    )
232  }
233
234  printPipeLine(store_s0.io.out.bits, store_s0.io.out.valid, "S0")
235  printPipeLine(store_s1.io.out.bits, store_s1.io.out.valid, "S1")
236}
237