xref: /XiangShan/src/main/scala/xiangshan/backend/fu/wrapper/VFMA.scala (revision 614d2bc6eead7bc6e6e71c4d6dc850d2d5ad3aef)
1package xiangshan.backend.fu.wrapper
2
3import org.chipsalliance.cde.config.Parameters
4import chisel3._
5import chisel3.util._
6import utility.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, VecPipedFuncUnit}
11import xiangshan.ExceptionNO
12import yunsuan.VfpuType
13import yunsuan.VfmaType
14import yunsuan.vector.VectorFloatFMA
15
16class VFMA(cfg: FuConfig)(implicit p: Parameters) extends VecPipedFuncUnit(cfg) {
17  XSError(io.in.valid && io.in.bits.ctrl.fuOpType === VfpuType.dummy, "Vfalu OpType not supported")
18
19  // params alias
20  private val dataWidth = cfg.destDataBits
21  private val dataWidthOfDataModule = 64
22  private val numVecModule = dataWidth / dataWidthOfDataModule
23
24  // io alias
25  private val opcode  = fuOpType(3,0)
26  private val resWiden  = fuOpType(4)
27
28  // modules
29  private val vfmas = Seq.fill(numVecModule)(Module(new VectorFloatFMA))
30  private val vs2Split = Module(new VecDataSplitModule(dataWidth, dataWidthOfDataModule))
31  private val vs1Split = Module(new VecDataSplitModule(dataWidth, dataWidthOfDataModule))
32  private val oldVdSplit  = Module(new VecDataSplitModule(dataWidth, dataWidthOfDataModule))
33  private val mgu = Module(new Mgu(dataWidth))
34
35  /**
36    * In connection of [[vs2Split]], [[vs1Split]] and [[oldVdSplit]]
37    */
38  vs2Split.io.inVecData := vs2
39  vs1Split.io.inVecData := vs1
40  oldVdSplit.io.inVecData := oldVd
41
42  /**
43    * [[vfmas]]'s in connection
44    */
45  // Vec(vs2(31,0), vs2(63,32), vs2(95,64), vs2(127,96)) ==>
46  // Vec(
47  //   Cat(vs2(95,64),  vs2(31,0)),
48  //   Cat(vs2(127,96), vs2(63,32)),
49  // )
50  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)
51  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)
52  private val resultData = Wire(Vec(numVecModule, UInt(dataWidthOfDataModule.W)))
53  private val fflagsData = Wire(Vec(numVecModule, UInt(20.W)))
54  val fp_aIsFpCanonicalNAN = Wire(Vec(numVecModule, Bool()))
55  val fp_bIsFpCanonicalNAN = Wire(Vec(numVecModule, Bool()))
56  val fp_cIsFpCanonicalNAN = Wire(Vec(numVecModule, Bool()))
57  vfmas.zipWithIndex.foreach {
58    case (mod, i) =>
59      mod.io.fire         := io.in.valid
60      mod.io.fp_a         := vs2Split.io.outVec64b(i)
61      mod.io.fp_b         := vs1Split.io.outVec64b(i)
62      mod.io.fp_c         := oldVdSplit.io.outVec64b(i)
63      mod.io.widen_a      := Cat(vs2Split.io.outVec32b(i+numVecModule), vs2Split.io.outVec32b(i))
64      mod.io.widen_b      := Cat(vs1Split.io.outVec32b(i+numVecModule), vs1Split.io.outVec32b(i))
65      mod.io.frs1         := 0.U     // already vf -> vv
66      mod.io.is_frs1      := false.B // already vf -> vv
67      mod.io.uop_idx      := vuopIdx(0)
68      mod.io.is_vec       := true.B // Todo
69      mod.io.round_mode   := rm
70      mod.io.fp_format    := Mux(resWiden, vsew + 1.U, vsew)
71      mod.io.res_widening := resWiden
72      mod.io.op_code      := opcode
73      resultData(i) := mod.io.fp_result
74      fflagsData(i) := mod.io.fflags
75      fp_aIsFpCanonicalNAN(i) := vecCtrl.fpu.isFpToVecInst & (
76        ((vsew === VSew.e32) & (!vs2Split.io.outVec64b(i).head(32).andR)) |
77          ((vsew === VSew.e16) & (!vs2Split.io.outVec64b(i).head(48).andR))
78        )
79      fp_bIsFpCanonicalNAN(i) := vecCtrl.fpu.isFpToVecInst & (
80        ((vsew === VSew.e32) & (!vs1Split.io.outVec64b(i).head(32).andR)) |
81          ((vsew === VSew.e16) & (!vs1Split.io.outVec64b(i).head(48).andR))
82        )
83      fp_cIsFpCanonicalNAN(i) := !(opcode === VfmaType.vfmul) & vecCtrl.fpu.isFpToVecInst & (
84        ((vsew === VSew.e32) & (!oldVdSplit.io.outVec64b(i).head(32).andR)) |
85          ((vsew === VSew.e16) & (!oldVdSplit.io.outVec64b(i).head(48).andR))
86        )
87      mod.io.fp_aIsFpCanonicalNAN := fp_aIsFpCanonicalNAN(i)
88      mod.io.fp_bIsFpCanonicalNAN := fp_bIsFpCanonicalNAN(i)
89      mod.io.fp_cIsFpCanonicalNAN := fp_cIsFpCanonicalNAN(i)
90  }
91
92  val outFuOpType = outCtrl.fuOpType
93  val outWiden = outCtrl.fuOpType(4)
94  val outEew = Mux(outWiden, outVecCtrl.vsew + 1.U, outVecCtrl.vsew)
95  val outVuopidx = outVecCtrl.vuopIdx(2, 0)
96  val vlMax = ((VLEN / 8).U >> outEew).asUInt
97  val outVlmulFix = Mux(outWiden, outVecCtrl.vlmul + 1.U, outVecCtrl.vlmul)
98  val lmulAbs = Mux(outVlmulFix(2), (~outVlmulFix(1, 0)).asUInt + 1.U, outVlmulFix(1, 0))
99  val outVlFix = Mux(outVecCtrl.fpu.isFpToVecInst, 1.U, outVl)
100  val vlMaxAllUop = Wire(outVl.cloneType)
101  vlMaxAllUop := Mux(outVecCtrl.vlmul(2), vlMax >> lmulAbs, vlMax << lmulAbs).asUInt
102  val vlMaxThisUop = Mux(outVecCtrl.vlmul(2), vlMax >> lmulAbs, vlMax).asUInt
103  val vlSetThisUop = Mux(outVlFix > outVuopidx * vlMaxThisUop, outVlFix - outVuopidx * vlMaxThisUop, 0.U)
104  val vlThisUop = Wire(UInt(4.W))
105  vlThisUop := Mux(vlSetThisUop < vlMaxThisUop, vlSetThisUop, vlMaxThisUop)
106  val vlMaskRShift = Wire(UInt((4 * numVecModule).W))
107  vlMaskRShift := Fill(4 * numVecModule, 1.U(1.W)) >> ((4 * numVecModule).U - vlThisUop)
108
109  private val needNoMask = outVecCtrl.fpu.isFpToVecInst
110  val maskToMgu = Mux(needNoMask, allMaskTrue, outSrcMask)
111  val allFFlagsEn = Wire(Vec(4 * numVecModule, Bool()))
112  val outSrcMaskRShift = Wire(UInt((4 * numVecModule).W))
113  outSrcMaskRShift := (maskToMgu >> (outVecCtrl.vuopIdx(2, 0) * vlMax))(4 * numVecModule - 1, 0)
114  val f16FFlagsEn = outSrcMaskRShift
115  val f32FFlagsEn = Wire(Vec(numVecModule, UInt(4.W)))
116  val f64FFlagsEn = Wire(Vec(numVecModule, UInt(4.W)))
117  val f16VlMaskEn = vlMaskRShift
118  val f32VlMaskEn = Wire(Vec(numVecModule, UInt(4.W)))
119  val f64VlMaskEn = Wire(Vec(numVecModule, UInt(4.W)))
120  for (i <- 0 until numVecModule) {
121    f32FFlagsEn(i) := Cat(Fill(2, 0.U), outSrcMaskRShift(2 * i + 1, 2 * i))
122    f64FFlagsEn(i) := Cat(Fill(3, 0.U), outSrcMaskRShift(i))
123    f32VlMaskEn(i) := Cat(Fill(2, 0.U), vlMaskRShift(2 * i + 1, 2 * i))
124    f64VlMaskEn(i) := Cat(Fill(3, 0.U), vlMaskRShift(i))
125  }
126  val fflagsEn = Mux1H(
127    Seq(
128      (outEew === 1.U) -> f16FFlagsEn.asUInt,
129      (outEew === 2.U) -> f32FFlagsEn.asUInt,
130      (outEew === 3.U) -> f64FFlagsEn.asUInt
131    )
132  )
133  val vlMaskEn = Mux1H(
134    Seq(
135      (outEew === 1.U) -> f16VlMaskEn.asUInt,
136      (outEew === 2.U) -> f32VlMaskEn.asUInt,
137      (outEew === 3.U) -> f64VlMaskEn.asUInt
138    )
139  )
140  allFFlagsEn := (fflagsEn & vlMaskEn).asTypeOf(allFFlagsEn)
141
142  val allFFlags = fflagsData.asTypeOf(Vec(4 * numVecModule, UInt(5.W)))
143  val outFFlags = allFFlagsEn.zip(allFFlags).map {
144    case (en, fflags) => Mux(en, fflags, 0.U(5.W))
145  }.reduce(_ | _)
146  io.out.bits.res.fflags.get := outFFlags
147
148  val resultDataUInt = resultData.asUInt
149  mgu.io.in.vd := resultDataUInt
150  mgu.io.in.oldVd := outOldVd
151  mgu.io.in.mask := maskToMgu
152  mgu.io.in.info.ta := outVecCtrl.vta
153  mgu.io.in.info.ma := outVecCtrl.vma
154  mgu.io.in.info.vl := Mux(outVecCtrl.fpu.isFpToVecInst, 1.U, outVl)
155  mgu.io.in.info.vlmul := outVecCtrl.vlmul
156  mgu.io.in.info.valid := io.out.valid
157  mgu.io.in.info.vstart := Mux(outVecCtrl.fpu.isFpToVecInst, 0.U, outVecCtrl.vstart)
158  mgu.io.in.info.eew := outEew
159  mgu.io.in.info.vsew := outVecCtrl.vsew
160  mgu.io.in.info.vdIdx := outVecCtrl.vuopIdx
161  mgu.io.in.info.narrow := outVecCtrl.isNarrow
162  mgu.io.in.info.dstMask := outVecCtrl.isDstMask
163  mgu.io.in.isIndexedVls := false.B
164  io.out.bits.res.data := mgu.io.out.vd
165  io.out.bits.ctrl.exceptionVec.get(ExceptionNO.illegalInstr) := mgu.io.out.illegal
166}
167