xref: /XiangShan/src/main/scala/xiangshan/frontend/Frontend.scala (revision df5b4b8e4c8c57d66a4b3cfef025a03fdc4199d0)
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.frontend
18import chipsalliance.rocketchip.config.Parameters
19import chisel3._
20import chisel3.util._
21import freechips.rocketchip.diplomacy.{LazyModule, LazyModuleImp}
22import utils._
23import xiangshan._
24import xiangshan.backend.fu.{PFEvent, PMP, PMPChecker}
25import xiangshan.cache.mmu.{TLB, TlbPtwIO}
26import xiangshan.frontend.icache._
27
28
29class Frontend()(implicit p: Parameters) extends LazyModule with HasXSParameter{
30
31  val instrUncache  = LazyModule(new InstrUncache())
32  val icache        = LazyModule(new ICache())
33
34  lazy val module = new FrontendImp(this)
35}
36
37
38class FrontendImp (outer: Frontend) extends LazyModuleImp(outer)
39  with HasXSParameter
40  with HasPerfEvents
41{
42  val io = IO(new Bundle() {
43    val fencei = Input(Bool())
44    val ptw = new TlbPtwIO(2)
45    val backend = new FrontendToCtrlIO
46    val sfence = Input(new SfenceBundle)
47    val tlbCsr = Input(new TlbCsrBundle)
48    val csrCtrl = Input(new CustomCSRCtrlIO)
49    val csrUpdate = new DistributedCSRUpdateReq
50    val error  = new L1CacheErrorInfo
51    val frontendInfo = new Bundle {
52      val ibufFull  = Output(Bool())
53      val bpuInfo = new Bundle {
54        val bpRight = Output(UInt(XLEN.W))
55        val bpWrong = Output(UInt(XLEN.W))
56      }
57    }
58  })
59
60  //decouped-frontend modules
61  val instrUncache = outer.instrUncache.module
62  val icache       = outer.icache.module
63  val bpu     = Module(new Predictor)
64  val ifu     = Module(new NewIFU)
65  val ibuffer =  Module(new Ibuffer)
66  val ftq = Module(new Ftq)
67
68  val tlbCsr = DelayN(io.tlbCsr, 2)
69  val csrCtrl = DelayN(io.csrCtrl, 2)
70
71  // trigger
72  ifu.io.frontendTrigger := csrCtrl.frontend_trigger
73  val triggerEn = csrCtrl.trigger_enable
74  ifu.io.csrTriggerEnable := VecInit(triggerEn(0), triggerEn(1), triggerEn(6), triggerEn(8))
75
76  // pmp
77  val pmp = Module(new PMP())
78  val pmp_check = VecInit(Seq.fill(2)(Module(new PMPChecker(3, sameCycle = true)).io))
79  pmp.io.distribute_csr := csrCtrl.distribute_csr
80  for (i <- pmp_check.indices) {
81    pmp_check(i).apply(tlbCsr.priv.imode, pmp.io.pmp, pmp.io.pma, icache.io.pmp(i).req)
82    icache.io.pmp(i).resp <> pmp_check(i).resp
83  }
84
85  io.ptw <> TLB(
86    in = Seq(icache.io.itlb(0), icache.io.itlb(1)),
87    sfence = io.sfence,
88    csr = tlbCsr,
89    width = 2,
90    shouldBlock = true,
91    itlbParams
92  )
93
94  icache.io.fencei := RegNext(io.fencei)
95
96  val needFlush = RegNext(io.backend.toFtq.redirect.valid)
97
98  //IFU-Ftq
99  ifu.io.ftqInter.fromFtq <> ftq.io.toIfu
100  ftq.io.fromIfu          <> ifu.io.ftqInter.toFtq
101  bpu.io.ftq_to_bpu       <> ftq.io.toBpu
102  ftq.io.fromBpu          <> bpu.io.bpu_to_ftq
103  //IFU-ICache
104  for(i <- 0 until 2){
105    ifu.io.icacheInter(i).req       <>      icache.io.fetch(i).req
106    icache.io.fetch(i).req <> ifu.io.icacheInter(i).req
107    ifu.io.icacheInter(i).resp <> icache.io.fetch(i).resp
108  }
109  icache.io.stop := ifu.io.icacheStop
110
111  ifu.io.icachePerfInfo := icache.io.perfInfo
112
113  //icache.io.missQueue.flush := ifu.io.ftqInter.fromFtq.redirect.valid || (ifu.io.ftqInter.toFtq.pdWb.valid && ifu.io.ftqInter.toFtq.pdWb.bits.misOffset.valid)
114
115  icache.io.csr.distribute_csr <> csrCtrl.distribute_csr
116  io.csrUpdate := RegNext(icache.io.csr.update)
117
118  //IFU-Ibuffer
119  ifu.io.toIbuffer    <> ibuffer.io.in
120
121  ftq.io.fromBackend <> io.backend.toFtq
122  io.backend.fromFtq <> ftq.io.toBackend
123  io.frontendInfo.bpuInfo <> ftq.io.bpuInfo
124
125  ifu.io.rob_commits <> io.backend.toFtq.rob_commits
126
127  ibuffer.io.flush := needFlush
128  io.backend.cfVec <> ibuffer.io.out
129
130  instrUncache.io.req   <> ifu.io.uncacheInter.toUncache
131  ifu.io.uncacheInter.fromUncache <> instrUncache.io.resp
132  instrUncache.io.flush := false.B//icache.io.missQueue.flush
133  io.error <> DontCare
134
135  val frontendBubble = PopCount((0 until DecodeWidth).map(i => io.backend.cfVec(i).ready && !ibuffer.io.out(i).valid))
136  XSPerfAccumulate("FrontendBubble", frontendBubble)
137  io.frontendInfo.ibufFull := RegNext(ibuffer.io.full)
138
139  // PFEvent
140  val pfevent = Module(new PFEvent)
141  pfevent.io.distribute_csr := io.csrCtrl.distribute_csr
142  val csrevents = pfevent.io.hpmevent.take(8)
143
144  val allPerfEvents = Seq(ifu, ibuffer, icache, ftq, bpu).flatMap(_.getPerf)
145  override val perfEvents = HPerfMonitor(csrevents, allPerfEvents).getPerfEvents
146  generatePerfEvent()
147}
148