xref: /XiangShan/src/main/scala/xiangshan/mem/pipeline/StoreUnit.scala (revision 12e221b1295bd5e50822d86f9ccd637ebeaffc2f)
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.robIdx := io.in.bits.uop.robIdx
54  io.dtlbReq.bits.debug.pc := io.in.bits.uop.cf.pc
55  io.dtlbReq.bits.debug.isFirstIssue := io.isFirstIssue
56
57  io.out.bits := DontCare
58  io.out.bits.vaddr := saddr
59
60  // Now data use its own io
61  // io.out.bits.data := genWdata(io.in.bits.src(1), io.in.bits.uop.ctrl.fuOpType(1,0))
62  io.out.bits.data := io.in.bits.src(1) // FIXME: remove data from pipeline
63  io.out.bits.uop := io.in.bits.uop
64  io.out.bits.miss := DontCare
65  io.out.bits.rsIdx := io.rsIdx
66  io.out.bits.mask := genWmask(io.out.bits.vaddr, io.in.bits.uop.ctrl.fuOpType(1,0))
67  io.out.bits.isFirstIssue := io.isFirstIssue
68  io.out.bits.wlineflag := io.in.bits.uop.ctrl.fuOpType === LSUOpType.cbo_zero
69  io.out.valid := io.in.valid
70  io.in.ready := io.out.ready
71
72  // exception check
73  val addrAligned = LookupTree(io.in.bits.uop.ctrl.fuOpType(1,0), List(
74    "b00".U   -> true.B,              //b
75    "b01".U   -> (io.out.bits.vaddr(0) === 0.U),   //h
76    "b10".U   -> (io.out.bits.vaddr(1,0) === 0.U), //w
77    "b11".U   -> (io.out.bits.vaddr(2,0) === 0.U)  //d
78  ))
79  io.out.bits.uop.cf.exceptionVec(storeAddrMisaligned) := !addrAligned
80
81  XSPerfAccumulate("in_valid", io.in.valid)
82  XSPerfAccumulate("in_fire", io.in.fire)
83  XSPerfAccumulate("in_fire_first_issue", io.in.fire && io.isFirstIssue)
84  XSPerfAccumulate("addr_spec_success", io.out.fire() && saddr(VAddrBits-1, 12) === io.in.bits.src(0)(VAddrBits-1, 12))
85  XSPerfAccumulate("addr_spec_failed", io.out.fire() && saddr(VAddrBits-1, 12) =/= io.in.bits.src(0)(VAddrBits-1, 12))
86  XSPerfAccumulate("addr_spec_success_once", io.out.fire() && saddr(VAddrBits-1, 12) === io.in.bits.src(0)(VAddrBits-1, 12) && io.isFirstIssue)
87  XSPerfAccumulate("addr_spec_failed_once", io.out.fire() && saddr(VAddrBits-1, 12) =/= io.in.bits.src(0)(VAddrBits-1, 12) && io.isFirstIssue)
88}
89
90// Store Pipeline Stage 1
91// TLB resp (send paddr to dcache)
92class StoreUnit_S1(implicit p: Parameters) extends XSModule {
93  val io = IO(new Bundle() {
94    val in = Flipped(Decoupled(new LsPipelineBundle))
95    val out = Decoupled(new LsPipelineBundle)
96    val lsq = ValidIO(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 = ExceptionNO.selectByFu(io.out.bits.uop.cf.exceptionVec, staCfg).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  io.lsq.valid := io.in.valid
139  io.lsq.bits := io.out.bits
140  io.lsq.bits.miss := s1_tlb_miss
141
142  // mmio inst with exception will be writebacked immediately
143  // io.out.valid := io.in.valid && (!io.out.bits.mmio || s1_exception) && !s1_tlb_miss
144
145  XSPerfAccumulate("in_valid", io.in.valid)
146  XSPerfAccumulate("in_fire", io.in.fire)
147  XSPerfAccumulate("in_fire_first_issue", io.in.fire && io.in.bits.isFirstIssue)
148  XSPerfAccumulate("tlb_miss", io.in.fire && s1_tlb_miss)
149  XSPerfAccumulate("tlb_miss_first_issue", io.in.fire && s1_tlb_miss && io.in.bits.isFirstIssue)
150}
151
152class StoreUnit_S2(implicit p: Parameters) extends XSModule {
153  val io = IO(new Bundle() {
154    val in = Flipped(Decoupled(new LsPipelineBundle))
155    val pmpResp = Flipped(new PMPRespBundle)
156    val static_pm = Input(Valid(Bool()))
157    val out = Decoupled(new LsPipelineBundle)
158  })
159  val pmp = WireInit(io.pmpResp)
160  when (io.static_pm.valid) {
161    pmp.ld := false.B
162    pmp.st := false.B
163    pmp.instr := false.B
164    pmp.mmio := io.static_pm.bits
165  }
166
167  val s2_exception = ExceptionNO.selectByFu(io.out.bits.uop.cf.exceptionVec, staCfg).asUInt.orR
168  val is_mmio = io.in.bits.mmio || pmp.mmio
169
170  io.in.ready := true.B
171  io.out.bits := io.in.bits
172  io.out.bits.mmio := is_mmio && !s2_exception
173  io.out.bits.uop.cf.exceptionVec(storeAccessFault) := io.in.bits.uop.cf.exceptionVec(storeAccessFault) || pmp.st
174  io.out.valid := io.in.valid && (!is_mmio || s2_exception)
175}
176
177class StoreUnit_S3(implicit p: Parameters) extends XSModule {
178  val io = IO(new Bundle() {
179    val in = Flipped(Decoupled(new LsPipelineBundle))
180    val stout = DecoupledIO(new ExuOutput) // writeback store
181  })
182
183  io.in.ready := true.B
184
185  io.stout.valid := io.in.valid
186  io.stout.bits.uop := io.in.bits.uop
187  io.stout.bits.data := DontCare
188  io.stout.bits.redirectValid := false.B
189  io.stout.bits.redirect := DontCare
190  io.stout.bits.debug.isMMIO := io.in.bits.mmio
191  io.stout.bits.debug.paddr := io.in.bits.paddr
192  io.stout.bits.debug.vaddr := io.in.bits.vaddr
193  io.stout.bits.debug.isPerfCnt := false.B
194  io.stout.bits.fflags := DontCare
195
196}
197
198class StoreUnit(implicit p: Parameters) extends XSModule {
199  val io = IO(new Bundle() {
200    val stin = Flipped(Decoupled(new ExuInput))
201    val redirect = Flipped(ValidIO(new Redirect))
202    val feedbackSlow = ValidIO(new RSFeedback)
203    val tlb = new TlbRequestIO()
204    val pmp = Flipped(new PMPRespBundle())
205    val rsIdx = Input(UInt(log2Up(IssQueSize).W))
206    val isFirstIssue = Input(Bool())
207    val lsq = ValidIO(new LsPipelineBundle)
208    val lsq_replenish = Output(new LsPipelineBundle())
209    val stout = DecoupledIO(new ExuOutput) // writeback store
210  })
211
212  val store_s0 = Module(new StoreUnit_S0)
213  val store_s1 = Module(new StoreUnit_S1)
214  val store_s2 = Module(new StoreUnit_S2)
215  val store_s3 = Module(new StoreUnit_S3)
216
217  store_s0.io.in <> io.stin
218  store_s0.io.dtlbReq <> io.tlb.req
219  store_s0.io.rsIdx := io.rsIdx
220  store_s0.io.isFirstIssue := io.isFirstIssue
221
222  PipelineConnect(store_s0.io.out, store_s1.io.in, true.B, store_s0.io.out.bits.uop.robIdx.needFlush(io.redirect))
223
224
225  store_s1.io.dtlbResp <> io.tlb.resp
226  store_s1.io.rsFeedback <> io.feedbackSlow
227  io.lsq <> store_s1.io.lsq
228
229  PipelineConnect(store_s1.io.out, store_s2.io.in, true.B, store_s1.io.out.bits.uop.robIdx.needFlush(io.redirect))
230
231  store_s2.io.pmpResp <> io.pmp
232  store_s2.io.static_pm := RegNext(io.tlb.resp.bits.static_pm)
233  io.lsq_replenish := store_s2.io.out.bits // mmio and exception
234  PipelineConnect(store_s2.io.out, store_s3.io.in, true.B, store_s2.io.out.bits.uop.robIdx.needFlush(io.redirect))
235
236  store_s3.io.stout <> io.stout
237
238  private def printPipeLine(pipeline: LsPipelineBundle, cond: Bool, name: String): Unit = {
239    XSDebug(cond,
240      p"$name" + p" pc ${Hexadecimal(pipeline.uop.cf.pc)} " +
241        p"addr ${Hexadecimal(pipeline.vaddr)} -> ${Hexadecimal(pipeline.paddr)} " +
242        p"op ${Binary(pipeline.uop.ctrl.fuOpType)} " +
243        p"data ${Hexadecimal(pipeline.data)} " +
244        p"mask ${Hexadecimal(pipeline.mask)}\n"
245    )
246  }
247
248  printPipeLine(store_s0.io.out.bits, store_s0.io.out.valid, "S0")
249  printPipeLine(store_s1.io.out.bits, store_s1.io.out.valid, "S1")
250}
251