xref: /XiangShan/src/main/scala/xiangshan/backend/fu/NewCSR/CSREvents/MNretEvent.scala (revision 26d03c882b233b6264a2eded969562fac9650e4a)
1package xiangshan.backend.fu.NewCSR.CSREvents
2
3import chisel3._
4import chisel3.util._
5import org.chipsalliance.cde.config.Parameters
6import utility.{SignExt, ZeroExt}
7import xiangshan.ExceptionNO
8import xiangshan.ExceptionNO._
9import xiangshan.backend.fu.NewCSR.CSRBundles.{CauseBundle, OneFieldBundle, PrivState}
10import xiangshan.backend.fu.NewCSR.CSRConfig.{VaddrMaxWidth, XLEN}
11import xiangshan.backend.fu.NewCSR.CSRDefines.{HgatpMode, PrivMode, SatpMode, VirtMode}
12import xiangshan.backend.fu.NewCSR._
13import xiangshan.AddrTransType
14
15
16class MNretEventOutput extends Bundle with EventUpdatePrivStateOutput with EventOutputBase {
17  val mnstatus  = ValidIO((new MnstatusBundle).addInEvent(_.MNPP, _.MNPV, _.NMIE))
18  val mstatus   = ValidIO((new MstatusBundle).addInEvent(_.MPRV, _.MDT, _.SDT))
19  val vsstatus  = ValidIO((new SstatusBundle).addInEvent(_.SDT))
20  val targetPc  = ValidIO(new TargetPCBundle)
21}
22
23class MNretEventInput extends Bundle {
24  val mnstatus = Input(new MnstatusBundle)
25  val mstatus  = Input(new MstatusBundle)
26  val mnepc    = Input(new Epc())
27  val satp     = Input(new SatpBundle)
28  val vsatp    = Input(new SatpBundle)
29  val hgatp    = Input(new HgatpBundle)
30  val vsstatus = Input(new SstatusBundle)
31}
32
33class MNretEventModule(implicit p: Parameters) extends Module with CSREventBase {
34  val in = IO(new MNretEventInput)
35  val out = IO(new MNretEventOutput)
36
37  private val satp = in.satp
38  private val vsatp = in.vsatp
39  private val hgatp = in.hgatp
40  private val nextPrivState = out.privState.bits
41
42  private val instrAddrTransType = AddrTransType(
43    bare = nextPrivState.isModeM ||
44           (!nextPrivState.isVirtual && satp.MODE === SatpMode.Bare) ||
45           (nextPrivState.isVirtual && vsatp.MODE === SatpMode.Bare && hgatp.MODE === HgatpMode.Bare),
46    sv39 = !nextPrivState.isModeM && !nextPrivState.isVirtual && satp.MODE === SatpMode.Sv39 ||
47           nextPrivState.isVirtual && vsatp.MODE === SatpMode.Sv39,
48    sv48 = !nextPrivState.isModeM && !nextPrivState.isVirtual && satp.MODE === SatpMode.Sv48 ||
49           nextPrivState.isVirtual && vsatp.MODE === SatpMode.Sv48,
50    sv39x4 = nextPrivState.isVirtual && vsatp.MODE === SatpMode.Bare && hgatp.MODE === HgatpMode.Sv39x4,
51    sv48x4 = nextPrivState.isVirtual && vsatp.MODE === SatpMode.Bare && hgatp.MODE === HgatpMode.Sv48x4
52  )
53
54  val outPrivState   = Wire(new PrivState)
55  outPrivState.PRVM := in.mnstatus.MNPP
56  outPrivState.V    := Mux(in.mnstatus.MNPP === PrivMode.M, VirtMode.Off.asUInt, in.mnstatus.MNPV.asUInt)
57
58  val mnretToM  = outPrivState.isModeM
59  val mnretToS  = outPrivState.isModeHS
60  val mnretToVU = outPrivState.isModeVU
61
62  out := DontCare
63
64  out.privState.valid := valid
65  out.mnstatus .valid := valid
66  out.mstatus  .valid := valid
67  out.vsstatus .valid := valid
68  out.targetPc .valid := valid
69
70  out.privState.bits          := outPrivState
71  out.mnstatus.bits.MNPP      := PrivMode.U
72  out.mnstatus.bits.MNPV      := VirtMode.Off.asUInt
73  out.mnstatus.bits.NMIE      := 1.U
74  out.mstatus.bits.MPRV       := Mux(in.mnstatus.MNPP =/= PrivMode.M, 0.U, in.mstatus.MPRV.asUInt)
75  // clear MDT when mnret to below M
76  out.mstatus.bits.MDT        := Mux(mnretToM, in.mstatus.MDT.asBool, 0.U)
77  out.mstatus.bits.SDT        := Mux(mnretToM || mnretToS, in.mstatus.SDT.asBool, 0.U)
78  out.vsstatus.bits.SDT       := Mux(mnretToVU, 0.U, in.vsstatus.SDT.asBool)
79  out.targetPc.bits.pc        := in.mnepc.asUInt
80  out.targetPc.bits.raiseIPF  := instrAddrTransType.checkPageFault(in.mnepc.asUInt)
81  out.targetPc.bits.raiseIAF  := instrAddrTransType.checkAccessFault(in.mnepc.asUInt)
82  out.targetPc.bits.raiseIGPF := instrAddrTransType.checkGuestPageFault(in.mnepc.asUInt)
83}
84
85trait MNretEventSinkBundle extends EventSinkBundle { self: CSRModule[_ <: CSRBundle] =>
86  val retFromMN = IO(Flipped(new MNretEventOutput))
87
88  addUpdateBundleInCSREnumType(retFromMN.getBundleByName(self.modName.toLowerCase()))
89
90  reconnectReg()
91}