xref: /XiangShan/src/main/scala/xiangshan/backend/fu/wrapper/VFDivSqrt.scala (revision 83ba63b34cf09b33c0a9e1b3203138e51af4491b)
1package xiangshan.backend.fu.wrapper
2
3import org.chipsalliance.cde.config.Parameters
4import chisel3._
5import chisel3.util._
6import utils.XSError
7import xiangshan.backend.fu.FuConfig
8import xiangshan.backend.fu.vector.Bundles.VSew
9import xiangshan.backend.fu.vector.utils.VecDataSplitModule
10import xiangshan.backend.fu.vector.{Mgu, VecNonPipedFuncUnit}
11import xiangshan.backend.rob.RobPtr
12import yunsuan.VfpuType
13import yunsuan.vector.VectorFloatDivider
14
15class VFDivSqrt(cfg: FuConfig)(implicit p: Parameters) extends VecNonPipedFuncUnit(cfg) {
16  XSError(io.in.valid && io.in.bits.ctrl.fuOpType === VfpuType.dummy, "Vfdiv OpType not supported")
17
18  // params alias
19  private val dataWidth = cfg.dataBits
20  private val dataWidthOfDataModule = 64
21  private val numVecModule = dataWidth / dataWidthOfDataModule
22
23  // io alias
24  private val opcode  = fuOpType(0)
25
26  // modules
27  private val vfdivs = Seq.fill(numVecModule)(Module(new VectorFloatDivider))
28  private val vs2Split = Module(new VecDataSplitModule(dataWidth, dataWidthOfDataModule))
29  private val vs1Split = Module(new VecDataSplitModule(dataWidth, dataWidthOfDataModule))
30  private val oldVdSplit  = Module(new VecDataSplitModule(dataWidth, dataWidthOfDataModule))
31  private val mgu = Module(new Mgu(dataWidth))
32
33  /**
34    * In connection of [[vs2Split]], [[vs1Split]] and [[oldVdSplit]]
35    */
36  vs2Split.io.inVecData := vs2
37  vs1Split.io.inVecData := vs1
38  oldVdSplit.io.inVecData := oldVd
39
40  /**
41    * [[vfdivs]]'s in connection
42    */
43  private val vs2GroupedVec: Vec[UInt] = VecInit(vs2Split.io.outVec32b.zipWithIndex.groupBy(_._2 % 2).map(x => x._1 -> x._2.map(_._1)).values.map(x => Cat(x.reverse)).toSeq)
44  private val vs1GroupedVec: Vec[UInt] = VecInit(vs1Split.io.outVec32b.zipWithIndex.groupBy(_._2 % 2).map(x => x._1 -> x._2.map(_._1)).values.map(x => Cat(x.reverse)).toSeq)
45  private val resultData = Wire(Vec(numVecModule, UInt(dataWidthOfDataModule.W)))
46  private val fflagsData = Wire(Vec(numVecModule, UInt(20.W)))
47  val fp_aIsFpCanonicalNAN = Wire(Vec(numVecModule, Bool()))
48  val fp_bIsFpCanonicalNAN = Wire(Vec(numVecModule, Bool()))
49
50  val thisRobIdx = Wire(new RobPtr)
51  when(io.in.ready){
52    thisRobIdx := io.in.bits.ctrl.robIdx
53  }.otherwise{
54    thisRobIdx := outCtrl.robIdx
55  }
56  vfdivs.zipWithIndex.foreach {
57    case (mod, i) =>
58      mod.io.start_valid_i  := io.in.valid
59      mod.io.finish_ready_i := io.out.ready & io.out.valid
60      mod.io.flush_i        := thisRobIdx.needFlush(io.flush)
61      mod.io.fp_format_i    := vsew
62      mod.io.opa_i          := vs2Split.io.outVec64b(i)
63      mod.io.opb_i          := vs1Split.io.outVec64b(i)
64      mod.io.frs2_i         := 0.U     // already vf -> vv
65      mod.io.frs1_i         := 0.U     // already vf -> vv
66      mod.io.is_frs2_i      := false.B // already vf -> vv
67      mod.io.is_frs1_i      := false.B // already vf -> vv
68      mod.io.is_sqrt_i      := opcode
69      mod.io.rm_i           := frm
70      mod.io.is_vec_i       := true.B // Todo
71      resultData(i) := mod.io.fpdiv_res_o
72      fflagsData(i) := mod.io.fflags_o
73      fp_aIsFpCanonicalNAN(i) := vecCtrl.fpu.isFpToVecInst & (
74        ((vsew === VSew.e32) & (!vs2Split.io.outVec64b(i).head(32).andR)) |
75          ((vsew === VSew.e16) & (!vs2Split.io.outVec64b(i).head(48).andR))
76        )
77      fp_bIsFpCanonicalNAN(i) := vecCtrl.fpu.isFpToVecInst & (
78        ((vsew === VSew.e32) & (!vs1Split.io.outVec64b(i).head(32).andR)) |
79          ((vsew === VSew.e16) & (!vs1Split.io.outVec64b(i).head(48).andR))
80        )
81      mod.io.fp_aIsFpCanonicalNAN := fp_aIsFpCanonicalNAN(i)
82      mod.io.fp_bIsFpCanonicalNAN := fp_bIsFpCanonicalNAN(i)
83  }
84
85  io.in.ready  := vfdivs.map(_.io.start_ready_o).reduce(_&_)
86  io.out.valid := vfdivs.map(_.io.finish_valid_o).reduce(_&_)
87  val outEew = outVecCtrl.vsew
88  val outVuopidx = outVecCtrl.vuopIdx(2, 0)
89  val vlMax = ((VLEN / 8).U >> outEew).asUInt
90  val lmulAbs = Mux(outVecCtrl.vlmul(2), (~outVecCtrl.vlmul(1, 0)).asUInt + 1.U, outVecCtrl.vlmul(1, 0))
91  val outVlFix = Mux(outVecCtrl.fpu.isFpToVecInst, 1.U, outVl)
92  val vlMaxAllUop = Wire(outVl.cloneType)
93  vlMaxAllUop := Mux(outVecCtrl.vlmul(2), vlMax >> lmulAbs, vlMax << lmulAbs).asUInt
94  val vlMaxThisUop = Mux(outVecCtrl.vlmul(2), vlMax >> lmulAbs, vlMax).asUInt
95  val vlSetThisUop = Mux(outVlFix > outVuopidx * vlMaxThisUop, outVlFix - outVuopidx * vlMaxThisUop, 0.U)
96  val vlThisUop = Wire(UInt(3.W))
97  vlThisUop := Mux(vlSetThisUop < vlMaxThisUop, vlSetThisUop, vlMaxThisUop)
98  val vlMaskRShift = Wire(UInt((4 * numVecModule).W))
99  vlMaskRShift := Fill(4 * numVecModule, 1.U(1.W)) >> ((4 * numVecModule).U - vlThisUop)
100
101  private val needNoMask = outVecCtrl.fpu.isFpToVecInst
102  val maskToMgu = Mux(needNoMask, allMaskTrue, outSrcMask)
103  val allFFlagsEn = Wire(Vec(4 * numVecModule, Bool()))
104  val outSrcMaskRShift = Wire(UInt((4 * numVecModule).W))
105  outSrcMaskRShift := (maskToMgu >> (outVecCtrl.vuopIdx(2, 0) * vlMax))(4 * numVecModule - 1, 0)
106  val f16FFlagsEn = outSrcMaskRShift
107  val f32FFlagsEn = Wire(Vec(numVecModule, UInt(4.W)))
108  for (i <- 0 until numVecModule) {
109    f32FFlagsEn(i) := Cat(Fill(2, 1.U), outSrcMaskRShift(2 * i + 1, 2 * i))
110  }
111  val f64FFlagsEn = Wire(Vec(numVecModule, UInt(4.W)))
112  for (i <- 0 until numVecModule) {
113    f64FFlagsEn(i) := Cat(Fill(3, 1.U), outSrcMaskRShift(i))
114  }
115  val fflagsEn = Mux1H(
116    Seq(
117      (outEew === 1.U) -> f16FFlagsEn.asUInt,
118      (outEew === 2.U) -> f32FFlagsEn.asUInt,
119      (outEew === 3.U) -> f64FFlagsEn.asUInt
120    )
121  )
122  allFFlagsEn := (fflagsEn & vlMaskRShift).asTypeOf(allFFlagsEn)
123
124  val allFFlags = fflagsData.asTypeOf(Vec(4 * numVecModule, UInt(5.W)))
125  val outFFlags = allFFlagsEn.zip(allFFlags).map {
126    case (en, fflags) => Mux(en, fflags, 0.U(5.W))
127  }.reduce(_ | _)
128  io.out.bits.res.fflags.get := outFFlags
129
130  val resultDataUInt = resultData.asUInt
131  mgu.io.in.vd := resultDataUInt
132  mgu.io.in.oldVd := outOldVd
133  mgu.io.in.mask := maskToMgu
134  mgu.io.in.info.ta := outVecCtrl.vta
135  mgu.io.in.info.ma := outVecCtrl.vma
136  mgu.io.in.info.vl := Mux(outVecCtrl.fpu.isFpToVecInst, 1.U, outVl)
137  mgu.io.in.info.vlmul := outVecCtrl.vlmul
138  mgu.io.in.info.valid := io.out.valid
139  mgu.io.in.info.vstart := Mux(outVecCtrl.fpu.isFpToVecInst, 0.U, outVecCtrl.vstart)
140  mgu.io.in.info.eew := outVecCtrl.vsew
141  mgu.io.in.info.vsew := outVecCtrl.vsew
142  mgu.io.in.info.vdIdx := outVecCtrl.vuopIdx
143  mgu.io.in.info.narrow := outVecCtrl.isNarrow
144  mgu.io.in.info.dstMask := outVecCtrl.isDstMask
145  io.out.bits.res.data := mgu.io.out.vd
146
147}
148