xref: /XiangShan/src/main/scala/xiangshan/backend/CtrlBlock.scala (revision 2d7c7105479bec3c329cf213502bd6a01cff7c0a)
1package xiangshan.backend
2
3import chisel3._
4import chisel3.util._
5import utils._
6import xiangshan._
7import xiangshan.backend.decode.DecodeStage
8import xiangshan.backend.rename.{BusyTable, Rename}
9import xiangshan.backend.brq.{Brq, BrqPcRead}
10import xiangshan.backend.dispatch.Dispatch
11import xiangshan.backend.exu._
12import xiangshan.backend.exu.Exu.exuConfigs
13import xiangshan.backend.regfile.RfReadPort
14import xiangshan.backend.roq.{Roq, RoqCSRIO, RoqPtr, RoqExceptionInfo}
15import xiangshan.mem.LsqEnqIO
16
17class CtrlToIntBlockIO extends XSBundle {
18  val enqIqCtrl = Vec(exuParameters.IntExuCnt, DecoupledIO(new MicroOp))
19  val readRf = Vec(NRIntReadPorts, Output(UInt(PhyRegIdxWidth.W)))
20  val jumpPc = Output(UInt(VAddrBits.W))
21  // int block only uses port 0~7
22  val readPortIndex = Vec(exuParameters.IntExuCnt, Output(UInt(log2Ceil(8 / 2).W))) // TODO parameterize 8 here
23  val redirect = ValidIO(new Redirect)
24  val flush = Output(Bool())
25}
26
27class CtrlToFpBlockIO extends XSBundle {
28  val enqIqCtrl = Vec(exuParameters.FpExuCnt, DecoupledIO(new MicroOp))
29  val readRf = Vec(NRFpReadPorts, Output(UInt(PhyRegIdxWidth.W)))
30  // fp block uses port 0~11
31  val readPortIndex = Vec(exuParameters.FpExuCnt, Output(UInt(log2Ceil((NRFpReadPorts - exuParameters.StuCnt) / 3).W)))
32  val redirect = ValidIO(new Redirect)
33  val flush = Output(Bool())
34}
35
36class CtrlToLsBlockIO extends XSBundle {
37  val enqIqCtrl = Vec(exuParameters.LsExuCnt, DecoupledIO(new MicroOp))
38  val enqLsq = Flipped(new LsqEnqIO)
39  val redirect = ValidIO(new Redirect)
40  val flush = Output(Bool())
41}
42
43class CtrlBlock extends XSModule with HasCircularQueuePtrHelper {
44  val io = IO(new Bundle {
45    val frontend = Flipped(new FrontendToBackendIO)
46    val fromIntBlock = Flipped(new IntBlockToCtrlIO)
47    val fromFpBlock = Flipped(new FpBlockToCtrlIO)
48    val fromLsBlock = Flipped(new LsBlockToCtrlIO)
49    val toIntBlock = new CtrlToIntBlockIO
50    val toFpBlock = new CtrlToFpBlockIO
51    val toLsBlock = new CtrlToLsBlockIO
52    val roqio = new Bundle {
53      // to int block
54      val toCSR = new RoqCSRIO
55      val exception = ValidIO(new RoqExceptionInfo)
56      // to mem block
57      val commits = new RoqCommitIO
58      val roqDeqPtr = Output(new RoqPtr)
59    }
60  })
61
62  val decode = Module(new DecodeStage)
63  val brq = Module(new Brq)
64  val rename = Module(new Rename)
65  val dispatch = Module(new Dispatch)
66  val intBusyTable = Module(new BusyTable(NRIntReadPorts, NRIntWritePorts))
67  val fpBusyTable = Module(new BusyTable(NRFpReadPorts, NRFpWritePorts))
68
69  val roqWbSize = NRIntWritePorts + NRFpWritePorts + exuParameters.StuCnt + 1
70
71  val roq = Module(new Roq(roqWbSize))
72
73  // When replay and mis-prediction have the same roqIdx,
74  // mis-prediction should have higher priority, since mis-prediction flushes the load instruction.
75  // Thus, only when mis-prediction roqIdx is after replay roqIdx, replay should be valid.
76  val redirect = Wire(Valid(new Redirect))
77  val flush = roq.io.flushOut.valid
78  val brqIsAfterLsq = isAfter(brq.io.redirectOut.bits.roqIdx, io.fromLsBlock.replay.bits.roqIdx)
79  redirect.bits := Mux(io.fromLsBlock.replay.valid && (!brq.io.redirectOut.valid || brqIsAfterLsq),
80    io.fromLsBlock.replay.bits, brq.io.redirectOut.bits)
81  redirect.valid := brq.io.redirectOut.valid || io.fromLsBlock.replay.valid
82
83  io.frontend.redirect.valid := RegNext(redirect.valid || roq.io.flushOut.valid)
84  io.frontend.redirect.bits := RegNext(Mux(roq.io.flushOut.valid, roq.io.flushOut.bits, redirect.bits.target))
85  io.frontend.cfiUpdateInfo <> brq.io.cfiInfo
86
87  decode.io.in <> io.frontend.cfVec
88  decode.io.enqBrq <> brq.io.enq
89
90  brq.io.redirect <> redirect
91  brq.io.flush <> flush
92  brq.io.bcommit <> roq.io.bcommit
93  brq.io.exuRedirectWb <> io.fromIntBlock.exuRedirect
94  brq.io.pcReadReq.brqIdx := dispatch.io.enqIQCtrl(0).bits.brTag // jump
95  io.toIntBlock.jumpPc := brq.io.pcReadReq.pc
96
97  // pipeline between decode and dispatch
98  val lastCycleRedirect = RegNext(redirect.valid || roq.io.flushOut.valid)
99  for (i <- 0 until RenameWidth) {
100    PipelineConnect(decode.io.out(i), rename.io.in(i), rename.io.in(i).ready, redirect.valid || flush || lastCycleRedirect)
101  }
102
103  rename.io.redirect := redirect.valid
104  rename.io.flush := flush
105  rename.io.roqCommits <> roq.io.commits
106  rename.io.out <> dispatch.io.fromRename
107  rename.io.renameBypass <> dispatch.io.renameBypass
108
109  dispatch.io.redirect <> redirect
110  dispatch.io.flush := flush
111  dispatch.io.enqRoq <> roq.io.enq
112  dispatch.io.enqLsq <> io.toLsBlock.enqLsq
113  dispatch.io.readIntRf <> io.toIntBlock.readRf
114  dispatch.io.readFpRf <> io.toFpBlock.readRf
115  dispatch.io.allocPregs.zipWithIndex.foreach { case (preg, i) =>
116    intBusyTable.io.allocPregs(i).valid := preg.isInt
117    fpBusyTable.io.allocPregs(i).valid := preg.isFp
118    intBusyTable.io.allocPregs(i).bits := preg.preg
119    fpBusyTable.io.allocPregs(i).bits := preg.preg
120  }
121  dispatch.io.numExist <> io.fromIntBlock.numExist ++ io.fromFpBlock.numExist ++ io.fromLsBlock.numExist
122  dispatch.io.enqIQCtrl <> io.toIntBlock.enqIqCtrl ++ io.toFpBlock.enqIqCtrl ++ io.toLsBlock.enqIqCtrl
123//  dispatch.io.enqIQData <> io.toIntBlock.enqIqData ++ io.toFpBlock.enqIqData ++ io.toLsBlock.enqIqData
124
125
126  fpBusyTable.io.flush := flush
127  intBusyTable.io.flush := flush
128  for((wb, setPhyRegRdy) <- io.fromIntBlock.wbRegs.zip(intBusyTable.io.wbPregs)){
129    setPhyRegRdy.valid := wb.valid && wb.bits.uop.ctrl.rfWen
130    setPhyRegRdy.bits := wb.bits.uop.pdest
131  }
132  for((wb, setPhyRegRdy) <- io.fromFpBlock.wbRegs.zip(fpBusyTable.io.wbPregs)){
133    setPhyRegRdy.valid := wb.valid && wb.bits.uop.ctrl.fpWen
134    setPhyRegRdy.bits := wb.bits.uop.pdest
135  }
136  intBusyTable.io.read <> dispatch.io.readIntState
137  fpBusyTable.io.read <> dispatch.io.readFpState
138
139  roq.io.redirect <> redirect
140  roq.io.exeWbResults.take(roqWbSize-1).zip(
141    io.fromIntBlock.wbRegs ++ io.fromFpBlock.wbRegs ++ io.fromLsBlock.stOut
142  ).foreach{
143    case(x, y) =>
144      x.bits := y.bits
145      x.valid := y.valid && !y.bits.redirectValid
146  }
147  roq.io.exeWbResults.last := brq.io.out
148
149  io.toIntBlock.redirect <> redirect
150  io.toIntBlock.flush <> flush
151  io.toFpBlock.redirect <> redirect
152  io.toFpBlock.flush <> flush
153  io.toLsBlock.redirect <> redirect
154  io.toLsBlock.flush <> flush
155
156  dispatch.io.readPortIndex.intIndex <> io.toIntBlock.readPortIndex
157  dispatch.io.readPortIndex.fpIndex <> io.toFpBlock.readPortIndex
158
159  // roq to int block
160  io.roqio.toCSR <> roq.io.csr
161  io.roqio.exception := roq.io.exception
162  // roq to mem block
163  io.roqio.roqDeqPtr := roq.io.roqDeqPtr
164  io.roqio.commits := roq.io.commits
165}
166