xref: /XiangShan/src/main/scala/xiangshan/backend/datapath/VldMergeUnit.scala (revision 9477429f7dc92dfd72de3908b8e953de2886a01d)
1package xiangshan.backend.datapath
2
3import org.chipsalliance.cde.config.Parameters
4import chisel3._
5import chisel3.util._
6import xiangshan._
7import xiangshan.backend.Bundles.{ExuOutput, MemExuOutput}
8import xiangshan.backend.exu.ExeUnitParams
9import xiangshan.backend.fu.vector.{ByteMaskTailGen, Mgu, VecInfo}
10import xiangshan.mem.GenUSMaskRegVL
11import yunsuan.vector.SewOH
12
13class VldMergeUnit(val params: ExeUnitParams)(implicit p: Parameters) extends XSModule {
14  val io = IO(new VldMergeUnitIO(params))
15
16  io.writeback.ready := io.writebackAfterMerge.ready
17  // [WARNING] MemBlock cannot provide oldVdPsrc!!!
18  io.oldVdReadAddr := io.writeback.bits.vls.get.oldVdPsrc
19  val wbReg = Reg(Valid(new ExuOutput(params)))
20  val mgu = Module(new Mgu(VLEN))
21  val vdAfterMerge = Wire(UInt(VLEN.W))
22
23  val wbFire = !io.writeback.bits.robIdx.needFlush(io.flush) && io.writeback.fire
24  wbReg.bits := Mux(wbFire, io.writeback.bits, wbReg.bits)
25  wbReg.valid := wbFire
26  mgu.io.in.vd := wbReg.bits.data
27  // oldVd is contained in data and is already masked with new data
28  mgu.io.in.oldVd := wbReg.bits.data
29  mgu.io.in.mask := wbReg.bits.vls.get.vpu.vmask
30  mgu.io.in.info.valid := wbReg.valid
31  mgu.io.in.info.ta := wbReg.bits.vls.get.isMasked || wbReg.bits.vls.get.vpu.vta
32  mgu.io.in.info.ma := wbReg.bits.vls.get.vpu.vma
33  mgu.io.in.info.vl := Mux(wbReg.bits.vls.get.isMasked, GenUSMaskRegVL(wbReg.bits.vls.get.vpu.vl), wbReg.bits.vls.get.vpu.vl)
34  mgu.io.in.info.vstart := wbReg.bits.vls.get.vpu.vstart
35  mgu.io.in.info.eew := wbReg.bits.vls.get.vpu.veew
36  mgu.io.in.info.vsew := wbReg.bits.vls.get.vpu.vsew
37  mgu.io.in.info.vdIdx := wbReg.bits.vls.get.vdIdxInField
38  mgu.io.in.info.vlmul := wbReg.bits.vls.get.vpu.vlmul
39  mgu.io.in.info.narrow := false.B  // never narrow
40  mgu.io.in.info.dstMask := false.B // vlm need not mask
41  mgu.io.in.isIndexedVls := wbReg.bits.vls.get.isIndexed
42
43  vdAfterMerge := mgu.io.out.vd
44
45  io.writebackAfterMerge.valid := wbReg.valid
46  io.writebackAfterMerge.bits := wbReg.bits
47  io.writebackAfterMerge.bits.vecWen.foreach(_ := wbReg.bits.vecWen.get)
48  io.writebackAfterMerge.bits.data := vdAfterMerge
49}
50
51class VldMergeUnitIO(param: ExeUnitParams)(implicit p: Parameters) extends XSBundle {
52  val flush = Flipped(ValidIO(new Redirect))
53  val writeback = Flipped(DecoupledIO(new ExuOutput(param)))
54  val oldVdReadData = Input(UInt(VLEN.W))
55  val oldVdReadAddr = Output(UInt(PhyRegIdxWidth.W))
56  val writebackAfterMerge = DecoupledIO(new ExuOutput(param))
57}