xref: /XiangShan/src/main/scala/xiangshan/backend/CtrlBlock.scala (revision 2199a01c65d5a7bf503c4b40771336a50a6f1122)
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}
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}
25
26class CtrlToFpBlockIO extends XSBundle {
27  val enqIqCtrl = Vec(exuParameters.FpExuCnt, DecoupledIO(new MicroOp))
28  val readRf = Vec(NRFpReadPorts, Output(UInt(PhyRegIdxWidth.W)))
29  // fp block uses port 0~11
30  val readPortIndex = Vec(exuParameters.FpExuCnt, Output(UInt(log2Ceil((NRFpReadPorts - exuParameters.StuCnt) / 3).W)))
31  val redirect = ValidIO(new Redirect)
32}
33
34class CtrlToLsBlockIO extends XSBundle {
35  val enqIqCtrl = Vec(exuParameters.LsExuCnt, DecoupledIO(new MicroOp))
36  val enqLsq = Flipped(new LsqEnqIO)
37  val redirect = ValidIO(new Redirect)
38}
39
40class CtrlBlock extends XSModule with HasCircularQueuePtrHelper {
41  val io = IO(new Bundle {
42    val frontend = Flipped(new FrontendToBackendIO)
43    val fromIntBlock = Flipped(new IntBlockToCtrlIO)
44    val fromFpBlock = Flipped(new FpBlockToCtrlIO)
45    val fromLsBlock = Flipped(new LsBlockToCtrlIO)
46    val toIntBlock = new CtrlToIntBlockIO
47    val toFpBlock = new CtrlToFpBlockIO
48    val toLsBlock = new CtrlToLsBlockIO
49    val roqio = new Bundle {
50      // to int block
51      val toCSR = new RoqCSRIO
52      val exception = ValidIO(new MicroOp)
53      val isInterrupt = Output(Bool())
54      // to mem block
55      val commits = new RoqCommitIO
56      val roqDeqPtr = Output(new RoqPtr)
57    }
58  })
59
60  val decode = Module(new DecodeStage)
61  val brq = Module(new Brq)
62  val rename = Module(new Rename)
63  val dispatch = Module(new Dispatch)
64  val intBusyTable = Module(new BusyTable(NRIntReadPorts, NRIntWritePorts))
65  val fpBusyTable = Module(new BusyTable(NRFpReadPorts, NRFpWritePorts))
66
67  val roqWbSize = NRIntWritePorts + NRFpWritePorts + exuParameters.StuCnt + 1
68
69  val roq = Module(new Roq(roqWbSize))
70
71  // When replay and mis-prediction have the same roqIdx,
72  // mis-prediction should have higher priority, since mis-prediction flushes the load instruction.
73  // Thus, only when mis-prediction roqIdx is after replay roqIdx, replay should be valid.
74  val brqIsAfterLsq = isAfter(brq.io.redirectOut.bits.roqIdx, io.fromLsBlock.replay.bits.roqIdx)
75  val redirectArb = Mux(io.fromLsBlock.replay.valid && (!brq.io.redirectOut.valid || brqIsAfterLsq),
76    io.fromLsBlock.replay.bits, brq.io.redirectOut.bits)
77  val redirectValid = roq.io.redirectOut.valid || brq.io.redirectOut.valid || io.fromLsBlock.replay.valid
78  val redirect = Mux(roq.io.redirectOut.valid, roq.io.redirectOut.bits, redirectArb)
79
80  io.frontend.redirect.valid := RegNext(redirectValid)
81  io.frontend.redirect.bits := RegNext(Mux(roq.io.redirectOut.valid, roq.io.redirectOut.bits.target, redirectArb.target))
82  io.frontend.cfiUpdateInfo <> brq.io.cfiInfo
83
84  decode.io.in <> io.frontend.cfVec
85  decode.io.enqBrq <> brq.io.enq
86
87  brq.io.redirect.valid <> redirectValid
88  brq.io.redirect.bits <> redirect
89  brq.io.bcommit <> roq.io.bcommit
90  brq.io.exuRedirectWb <> io.fromIntBlock.exuRedirect
91  brq.io.pcReadReq.brqIdx := dispatch.io.enqIQCtrl(0).bits.brTag // jump
92  io.toIntBlock.jumpPc := brq.io.pcReadReq.pc
93
94  // pipeline between decode and dispatch
95  val lastCycleRedirect = RegNext(redirectValid)
96  for (i <- 0 until RenameWidth) {
97    PipelineConnect(decode.io.out(i), rename.io.in(i), rename.io.in(i).ready, redirectValid || lastCycleRedirect)
98  }
99
100  rename.io.redirect.valid <> redirectValid
101  rename.io.redirect.bits <> redirect
102  rename.io.roqCommits <> roq.io.commits
103  rename.io.out <> dispatch.io.fromRename
104  rename.io.renameBypass <> dispatch.io.renameBypass
105
106  dispatch.io.redirect.valid <> redirectValid
107  dispatch.io.redirect.bits <> redirect
108  dispatch.io.enqRoq <> roq.io.enq
109  dispatch.io.enqLsq <> io.toLsBlock.enqLsq
110  dispatch.io.readIntRf <> io.toIntBlock.readRf
111  dispatch.io.readFpRf <> io.toFpBlock.readRf
112  dispatch.io.allocPregs.zipWithIndex.foreach { case (preg, i) =>
113    intBusyTable.io.allocPregs(i).valid := preg.isInt
114    fpBusyTable.io.allocPregs(i).valid := preg.isFp
115    intBusyTable.io.allocPregs(i).bits := preg.preg
116    fpBusyTable.io.allocPregs(i).bits := preg.preg
117  }
118  dispatch.io.numExist <> io.fromIntBlock.numExist ++ io.fromFpBlock.numExist ++ io.fromLsBlock.numExist
119  dispatch.io.enqIQCtrl <> io.toIntBlock.enqIqCtrl ++ io.toFpBlock.enqIqCtrl ++ io.toLsBlock.enqIqCtrl
120//  dispatch.io.enqIQData <> io.toIntBlock.enqIqData ++ io.toFpBlock.enqIqData ++ io.toLsBlock.enqIqData
121
122
123  val flush = redirectValid && RedirectLevel.isUnconditional(redirect.level)
124  fpBusyTable.io.flush := flush
125  intBusyTable.io.flush := flush
126  for((wb, setPhyRegRdy) <- io.fromIntBlock.wbRegs.zip(intBusyTable.io.wbPregs)){
127    setPhyRegRdy.valid := wb.valid && wb.bits.uop.ctrl.rfWen
128    setPhyRegRdy.bits := wb.bits.uop.pdest
129  }
130  for((wb, setPhyRegRdy) <- io.fromFpBlock.wbRegs.zip(fpBusyTable.io.wbPregs)){
131    setPhyRegRdy.valid := wb.valid && wb.bits.uop.ctrl.fpWen
132    setPhyRegRdy.bits := wb.bits.uop.pdest
133  }
134  intBusyTable.io.read <> dispatch.io.readIntState
135  fpBusyTable.io.read <> dispatch.io.readFpState
136
137  roq.io.redirect.valid := brq.io.redirectOut.valid || io.fromLsBlock.replay.valid
138  roq.io.redirect.bits <> redirectArb
139  roq.io.exeWbResults.take(roqWbSize-1).zip(
140    io.fromIntBlock.wbRegs ++ io.fromFpBlock.wbRegs ++ io.fromLsBlock.stOut
141  ).foreach{
142    case(x, y) =>
143      x.bits := y.bits
144      x.valid := y.valid && !y.bits.redirectValid
145  }
146  roq.io.exeWbResults.last := brq.io.out
147
148  io.toIntBlock.redirect.valid := redirectValid
149  io.toIntBlock.redirect.bits := redirect
150  io.toFpBlock.redirect.valid := redirectValid
151  io.toFpBlock.redirect.bits := redirect
152  io.toLsBlock.redirect.valid := redirectValid
153  io.toLsBlock.redirect.bits := redirect
154
155  dispatch.io.readPortIndex.intIndex <> io.toIntBlock.readPortIndex
156  dispatch.io.readPortIndex.fpIndex <> io.toFpBlock.readPortIndex
157
158  // roq to int block
159  io.roqio.toCSR <> roq.io.csr
160  io.roqio.exception.valid := roq.io.redirectOut.valid && roq.io.redirectOut.bits.isException()
161  io.roqio.exception.bits := roq.io.exception
162  io.roqio.isInterrupt := roq.io.redirectOut.bits.interrupt
163  // roq to mem block
164  io.roqio.roqDeqPtr := roq.io.roqDeqPtr
165  io.roqio.commits := roq.io.commits
166}
167