xref: /XiangShan/src/main/scala/xiangshan/backend/CtrlBlock.scala (revision 76523708117cdaf87397f1c4ecd0fe44c77df511)
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, RoqLsqIO, 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 lsq = new RoqLsqIO
56    }
57  })
58
59  val difftestIO = IO(new Bundle() {
60    val fromRoq = new Bundle() {
61      val commit = Output(UInt(32.W))
62      val thisPC = Output(UInt(XLEN.W))
63      val thisINST = Output(UInt(32.W))
64      val skip = Output(UInt(32.W))
65      val wen = Output(UInt(32.W))
66      val wdata = Output(Vec(CommitWidth, UInt(XLEN.W))) // set difftest width to 6
67      val wdst = Output(Vec(CommitWidth, UInt(32.W))) // set difftest width to 6
68      val wpc = Output(Vec(CommitWidth, UInt(XLEN.W))) // set difftest width to 6
69      val isRVC = Output(UInt(32.W))
70      val scFailed = Output(Bool())
71    }
72  })
73  difftestIO <> DontCare
74
75  val decode = Module(new DecodeStage)
76  val brq = Module(new Brq)
77  val rename = Module(new Rename)
78  val dispatch = Module(new Dispatch)
79  val intBusyTable = Module(new BusyTable(NRIntReadPorts, NRIntWritePorts))
80  val fpBusyTable = Module(new BusyTable(NRFpReadPorts, NRFpWritePorts))
81
82  val roqWbSize = NRIntWritePorts + NRFpWritePorts + exuParameters.StuCnt + 1
83
84  val roq = Module(new Roq(roqWbSize))
85
86  // When replay and mis-prediction have the same roqIdx,
87  // mis-prediction should have higher priority, since mis-prediction flushes the load instruction.
88  // Thus, only when mis-prediction roqIdx is after replay roqIdx, replay should be valid.
89  val brqIsAfterLsq = isAfter(brq.io.redirectOut.bits.roqIdx, io.fromLsBlock.replay.bits.roqIdx)
90  val redirectArb = Mux(io.fromLsBlock.replay.valid && (!brq.io.redirectOut.valid || brqIsAfterLsq),
91    io.fromLsBlock.replay.bits, brq.io.redirectOut.bits)
92  val redirectValid = roq.io.redirectOut.valid || brq.io.redirectOut.valid || io.fromLsBlock.replay.valid
93  val redirect = Mux(roq.io.redirectOut.valid, roq.io.redirectOut.bits, redirectArb)
94
95  io.frontend.redirect.valid := RegNext(redirectValid)
96  io.frontend.redirect.bits := RegNext(Mux(roq.io.redirectOut.valid, roq.io.redirectOut.bits.target, redirectArb.target))
97  io.frontend.cfiUpdateInfo <> brq.io.cfiInfo
98
99  decode.io.in <> io.frontend.cfVec
100  decode.io.enqBrq <> brq.io.enq
101
102  brq.io.redirect.valid <> redirectValid
103  brq.io.redirect.bits <> redirect
104  brq.io.bcommit <> roq.io.bcommit
105  brq.io.exuRedirectWb <> io.fromIntBlock.exuRedirect
106  brq.io.pcReadReq.brqIdx := dispatch.io.enqIQCtrl(0).bits.brTag // jump
107  io.toIntBlock.jumpPc := brq.io.pcReadReq.pc
108
109  // pipeline between decode and dispatch
110  val lastCycleRedirect = RegNext(redirectValid)
111  for (i <- 0 until RenameWidth) {
112    PipelineConnect(decode.io.out(i), rename.io.in(i), rename.io.in(i).ready, redirectValid || lastCycleRedirect)
113  }
114
115  rename.io.redirect.valid <> redirectValid
116  rename.io.redirect.bits <> redirect
117  rename.io.roqCommits <> roq.io.commits
118  rename.io.out <> dispatch.io.fromRename
119  rename.io.renameBypass <> dispatch.io.renameBypass
120
121  dispatch.io.redirect.valid <> redirectValid
122  dispatch.io.redirect.bits <> redirect
123  dispatch.io.enqRoq <> roq.io.enq
124  dispatch.io.enqLsq <> io.toLsBlock.enqLsq
125  dispatch.io.readIntRf <> io.toIntBlock.readRf
126  dispatch.io.readFpRf <> io.toFpBlock.readRf
127  dispatch.io.allocPregs.zipWithIndex.foreach { case (preg, i) =>
128    intBusyTable.io.allocPregs(i).valid := preg.isInt
129    fpBusyTable.io.allocPregs(i).valid := preg.isFp
130    intBusyTable.io.allocPregs(i).bits := preg.preg
131    fpBusyTable.io.allocPregs(i).bits := preg.preg
132  }
133  dispatch.io.numExist <> io.fromIntBlock.numExist ++ io.fromFpBlock.numExist ++ io.fromLsBlock.numExist
134  dispatch.io.enqIQCtrl <> io.toIntBlock.enqIqCtrl ++ io.toFpBlock.enqIqCtrl ++ io.toLsBlock.enqIqCtrl
135//  dispatch.io.enqIQData <> io.toIntBlock.enqIqData ++ io.toFpBlock.enqIqData ++ io.toLsBlock.enqIqData
136
137
138  val flush = redirectValid && RedirectLevel.isUnconditional(redirect.level)
139  fpBusyTable.io.flush := flush
140  intBusyTable.io.flush := flush
141  for((wb, setPhyRegRdy) <- io.fromIntBlock.wbRegs.zip(intBusyTable.io.wbPregs)){
142    setPhyRegRdy.valid := wb.valid && wb.bits.uop.ctrl.rfWen
143    setPhyRegRdy.bits := wb.bits.uop.pdest
144  }
145  for((wb, setPhyRegRdy) <- io.fromFpBlock.wbRegs.zip(fpBusyTable.io.wbPregs)){
146    setPhyRegRdy.valid := wb.valid && wb.bits.uop.ctrl.fpWen
147    setPhyRegRdy.bits := wb.bits.uop.pdest
148  }
149  intBusyTable.io.read <> dispatch.io.readIntState
150  fpBusyTable.io.read <> dispatch.io.readFpState
151
152  roq.io.redirect.valid := brq.io.redirectOut.valid || io.fromLsBlock.replay.valid
153  roq.io.redirect.bits <> redirectArb
154  roq.io.exeWbResults.take(roqWbSize-1).zip(
155    io.fromIntBlock.wbRegs ++ io.fromFpBlock.wbRegs ++ io.fromLsBlock.stOut
156  ).foreach{
157    case(x, y) =>
158      x.bits := y.bits
159      x.valid := y.valid && !y.bits.redirectValid
160  }
161  roq.io.exeWbResults.last := brq.io.out
162
163  if (env.DualCoreDifftest) {
164    difftestIO.fromRoq <> roq.difftestIO
165  }
166
167  io.toIntBlock.redirect.valid := redirectValid
168  io.toIntBlock.redirect.bits := redirect
169  io.toFpBlock.redirect.valid := redirectValid
170  io.toFpBlock.redirect.bits := redirect
171  io.toLsBlock.redirect.valid := redirectValid
172  io.toLsBlock.redirect.bits := redirect
173
174  dispatch.io.readPortIndex.intIndex <> io.toIntBlock.readPortIndex
175  dispatch.io.readPortIndex.fpIndex <> io.toFpBlock.readPortIndex
176
177  // roq to int block
178  io.roqio.toCSR <> roq.io.csr
179  io.roqio.exception.valid := roq.io.redirectOut.valid && roq.io.redirectOut.bits.isException()
180  io.roqio.exception.bits := roq.io.exception
181  io.roqio.isInterrupt := roq.io.redirectOut.bits.interrupt
182  // roq to mem block
183  io.roqio.lsq <> roq.io.lsq
184}
185