feat(Ss/Smdbltrp) : Support RISC-V Ss/Smdbltrp Extension

src/main/scala/xiangshan/backend/fu/NewCSR/CSRBundles.scala

@@ -47,6 +47,7 @@ object CSRBundles {
     val STCE  =      RO(    63)           .withReset(0.U) // Sstc Enable
     val PBMTE =      RO(    62)           .withReset(0.U) // Svpbmt Enable
     val ADUE  =      RO(    61)           .withReset(0.U) // Svadu extension Enable
+    val DTE   =      RO(    59)           .withReset(0.U) // Ssdbltrp extension Enable
     val PMM   =      RO(33, 32)           .withReset(0.U) // Smnpm extension
     val CBZE  =      RW(     7)           .withReset(1.U) // Zicboz extension
     val CBCFE =      RW(     6)           .withReset(1.U) // Zicbom extension

src/main/scala/xiangshan/backend/fu/NewCSR/CSREvents/CSREvent.scala

@@ -125,6 +125,7 @@ class TrapEntryEventInput(implicit val p: Parameters) extends Bundle with HasXSP
   val isFetchMalAddr = Input(Bool())
   val isFetchBkpt = Input(Bool())
   val trapIsForVSnonLeafPTE = Input(Bool())
+  val hasDTExcp = Input(Bool())
 
   // always current privilege
   val iMode = Input(new PrivState())
@@ -136,6 +137,9 @@ class TrapEntryEventInput(implicit val p: Parameters) extends Bundle with HasXSP
   val hstatus = Input(new HstatusBundle)
   val sstatus = Input(new SstatusBundle)
   val vsstatus = Input(new SstatusBundle)
+  // envcfg
+  val menvcfg = Input(new MEnvCfg)
+  val henvcfg = Input(new HEnvCfg)
 
   val pcFromXtvec = Input(UInt(XLEN.W))
 

src/main/scala/xiangshan/backend/fu/NewCSR/CSREvents/MNretEvent.scala

@@ -15,7 +15,8 @@ import xiangshan.AddrTransType
 
 class MNretEventOutput extends Bundle with EventUpdatePrivStateOutput with EventOutputBase {
   val mnstatus  = ValidIO((new MnstatusBundle).addInEvent(_.MNPP, _.MNPV, _.NMIE))
-  val mstatus   = ValidIO((new MstatusBundle).addInEvent(_.MPRV))
+  val mstatus   = ValidIO((new MstatusBundle).addInEvent(_.MPRV, _.MDT, _.SDT))
+  val vsstatus  = ValidIO((new SstatusBundle).addInEvent(_.SDT))
   val targetPc  = ValidIO(new TargetPCBundle)
 }
 
@@ -26,6 +27,7 @@ class MNretEventInput extends Bundle {
   val satp     = Input(new SatpBundle)
   val vsatp    = Input(new SatpBundle)
   val hgatp    = Input(new HgatpBundle)
+  val vsstatus = Input(new SstatusBundle)
 }
 
 class MNretEventModule(implicit p: Parameters) extends Module with CSREventBase {
@@ -49,18 +51,29 @@ class MNretEventModule(implicit p: Parameters) extends Module with CSREventBase
     sv48x4 = nextPrivState.isVirtual && vsatp.MODE === SatpMode.Bare && hgatp.MODE === HgatpMode.Sv48x4
   )
 
+  val outPrivState   = Wire(new PrivState)
+  outPrivState.PRVM := in.mnstatus.MNPP
+  outPrivState.V    := Mux(in.mnstatus.MNPP === PrivMode.M, VirtMode.Off.asUInt, in.mnstatus.MNPV.asUInt)
+
+  val mnretToM  = outPrivState.isModeM
+  val mnretToS  = outPrivState.isModeHS
+  val mnretToVU = outPrivState.isModeVU
+
   out := DontCare
 
   out.privState.valid := valid
   out.mnstatus .valid := valid
   out.targetPc .valid := valid
 
-  out.privState.bits.PRVM     := in.mnstatus.MNPP
-  out.privState.bits.V        := Mux(in.mnstatus.MNPP === PrivMode.M, VirtMode.Off.asUInt, in.mnstatus.MNPV.asUInt)
+  out.privState.bits          := outPrivState
   out.mnstatus.bits.MNPP      := PrivMode.U
   out.mnstatus.bits.MNPV      := VirtMode.Off.asUInt
   out.mnstatus.bits.NMIE      := 1.U
   out.mstatus.bits.MPRV       := Mux(in.mnstatus.MNPP =/= PrivMode.M, 0.U, in.mstatus.MPRV.asUInt)
+  // clear MDT when mnret to below M
+  out.mstatus.bits.MDT        := Mux(mnretToM, in.mstatus.MDT.asBool, 0.U)
+  out.mstatus.bits.SDT        := Mux(mnretToM || mnretToS, in.mstatus.SDT.asBool, 0.U)
+  out.vsstatus.bits.SDT       := Mux(mnretToVU, 0.U, in.vsstatus.SDT.asBool)
   out.targetPc.bits.pc        := in.mnepc.asUInt
   out.targetPc.bits.raiseIPF  := instrAddrTransType.checkPageFault(in.mnepc.asUInt)
   out.targetPc.bits.raiseIAF  := instrAddrTransType.checkAccessFault(in.mnepc.asUInt)

src/main/scala/xiangshan/backend/fu/NewCSR/CSREvents/MretEvent.scala

@@ -14,12 +14,14 @@ import xiangshan.AddrTransType
 
 
 class MretEventOutput extends Bundle with EventUpdatePrivStateOutput with EventOutputBase {
-  val mstatus  = ValidIO((new MstatusBundle).addInEvent(_.MPP, _.MPV, _.MIE, _.MPIE, _.MPRV))
+  val mstatus  = ValidIO((new MstatusBundle).addInEvent(_.MPP, _.MPV, _.MIE, _.MPIE, _.MPRV, _.MDT, _.SDT))
+  val vsstatus = ValidIO((new SstatusBundle).addInEvent(_.SDT))
   val targetPc = ValidIO(new TargetPCBundle)
 }
 
 class MretEventInput extends Bundle {
   val mstatus  = Input(new MstatusBundle)
+  val vsstatus = Input(new SstatusBundle)
   val mepc     = Input(new Epc())
   val satp     = Input(new SatpBundle)
   val vsatp    = Input(new SatpBundle)
@@ -46,20 +48,33 @@ class MretEventModule(implicit p: Parameters) extends Module with CSREventBase {
     sv39x4 = nextPrivState.isVirtual && vsatp.MODE === SatpMode.Bare && hgatp.MODE === HgatpMode.Sv39x4,
     sv48x4 = nextPrivState.isVirtual && vsatp.MODE === SatpMode.Bare && hgatp.MODE === HgatpMode.Sv48x4
   )
+  val outPrivState   = Wire(new PrivState)
+  outPrivState.PRVM := in.mstatus.MPP
+  outPrivState.V    := Mux(in.mstatus.MPP === PrivMode.M, VirtMode.Off.asUInt, in.mstatus.MPV.asUInt)
+
+  val mretToM  = outPrivState.isModeM
+  val mretToS  = outPrivState.isModeHS
+  val mretToVu = outPrivState.isModeVU
 
   out := DontCare
 
   out.privState.valid := valid
   out.mstatus  .valid := valid
   out.targetPc .valid := valid
 
-  out.privState.bits.PRVM     := in.mstatus.MPP
-  out.privState.bits.V        := Mux(in.mstatus.MPP === PrivMode.M, VirtMode.Off.asUInt, in.mstatus.MPV.asUInt)
+  out.privState.bits          := outPrivState
   out.mstatus.bits.MPP        := PrivMode.U
   out.mstatus.bits.MPV        := VirtMode.Off.asUInt
   out.mstatus.bits.MIE        := in.mstatus.MPIE
   out.mstatus.bits.MPIE       := 1.U
   out.mstatus.bits.MPRV       := Mux(in.mstatus.MPP =/= PrivMode.M, 0.U, in.mstatus.MPRV.asUInt)
+  // clear MDT when return mret always execute in M mode
+  out.mstatus.bits.MDT    := 0.U
+  // clear sstatus.SDT when return mode below M and HS
+  out.mstatus.bits.SDT    := Mux(mretToM || mretToS, in.mstatus.SDT.asBool, 0.U)
+  // clear vsstatus.SDT when return to VU
+  out.vsstatus.bits.SDT   := Mux(mretToVu, 0.U, in.vsstatus.SDT.asBool)
+
   out.targetPc.bits.pc        := in.mepc.asUInt
   out.targetPc.bits.raiseIPF  := instrAddrTransType.checkPageFault(in.mepc.asUInt)
   out.targetPc.bits.raiseIAF  := instrAddrTransType.checkAccessFault(in.mepc.asUInt)

src/main/scala/xiangshan/backend/fu/NewCSR/CSREvents/SretEvent.scala

@@ -15,15 +15,15 @@ import xiangshan.AddrTransType
 
 class SretEventOutput extends Bundle with EventUpdatePrivStateOutput with EventOutputBase {
   // Todo: write sstatus instead of mstatus
-  val mstatus = ValidIO((new MstatusBundle).addInEvent(_.SIE, _.SPIE, _.SPP, _.MPRV))
+  val mstatus = ValidIO((new MstatusBundle).addInEvent(_.SIE, _.SPIE, _.SPP, _.MPRV, _.MDT, _.SDT))
   val hstatus = ValidIO((new HstatusBundle).addInEvent(_.SPV))
-  val vsstatus = ValidIO((new SstatusBundle).addInEvent(_.SIE, _.SPIE, _.SPP))
+  val vsstatus = ValidIO((new SstatusBundle).addInEvent(_.SIE, _.SPIE, _.SPP, _.SDT))
   val targetPc = ValidIO(new TargetPCBundle)
 }
 
 class SretEventInput extends Bundle {
   val privState = Input(new PrivState)
-  val sstatus   = Input(new SstatusBundle)
+  val mstatus   = Input(new MstatusBundle)
   val hstatus   = Input(new HstatusBundle)
   val vsstatus  = Input(new SstatusBundle)
   val sepc      = Input(new Epc())
@@ -53,45 +53,62 @@ class SretEventModule(implicit p: Parameters) extends Module with CSREventBase {
     sv48x4 = nextPrivState.isVirtual && vsatp.MODE === SatpMode.Bare && hgatp.MODE === HgatpMode.Sv48x4
   )
 
-  private val sretInHSorM = in.privState.isModeM || in.privState.isModeHS
+  private val sretInM     = in.privState.isModeM
+  private val sretInHS    = in.privState.isModeHS
+  private val sretInHSorM = sretInM || sretInHS
   private val sretInVS    = in.privState.isModeVS
 
   private val xepc = Mux1H(Seq(
     sretInHSorM -> in.sepc,
     sretInVS    -> in.vsepc,
   )).asUInt
 
-  out := DontCare
-
-  out.privState.valid := valid
-  out.targetPc .valid := valid
 
-  out.privState.bits.PRVM     := Mux1H(Seq(
+  private val outPrivState   = Wire(new PrivState)
+  outPrivState.PRVM := Mux1H(Seq(
     // SPP is not PrivMode enum type, so asUInt
-    sretInHSorM -> in.sstatus.SPP.asUInt,
+    sretInHSorM -> in.mstatus.SPP.asUInt,
     sretInVS    -> in.vsstatus.SPP.asUInt,
   ))
-  out.privState.bits.V        := Mux1H(Seq(
+  outPrivState.V := Mux1H(Seq(
     sretInHSorM -> in.hstatus.SPV,
     sretInVS    -> in.privState.V, // keep
   ))
 
+  private val sretToVU    = outPrivState.isModeVU
+  private val sretToVS    = outPrivState.isModeVS
+  private val sretToU     = outPrivState.isModeHU
+
+  out := DontCare
+
+  out.privState.valid := valid
+  out.targetPc .valid := valid
+
+  out.privState.bits      := outPrivState
+
   // hstatus
   out.hstatus.valid           := valid && sretInHSorM
   out.hstatus.bits.SPV        := VirtMode.Off
 
   // sstatus
   out.mstatus.valid           := valid && sretInHSorM
   out.mstatus.bits.SPP        := PrivMode.U.asUInt(0, 0) // SPP is not PrivMode enum type, so asUInt and shrink the width
-  out.mstatus.bits.SIE        := in.sstatus.SPIE
+  out.mstatus.bits.SIE        := in.mstatus.SPIE
   out.mstatus.bits.SPIE       := 1.U
   out.mstatus.bits.MPRV       := 0.U // sret will always leave M mode
+  out.mstatus.bits.MDT        := Mux(sretInM, 0.U, in.mstatus.MDT.asBool) // when execute return in M mode, set MDT 0
+  out.mstatus.bits.SDT        := MuxCase(in.mstatus.SDT.asBool, Seq(
+    sretInHS   -> 0.U, // sret will alway leave M mode
+    (sretInM && (sretToU || sretToVS || sretToVU))    -> 0.U
+  ))
+
 
   // vsstatus
   out.vsstatus.valid          := valid && sretInVS
   out.vsstatus.bits.SPP       := PrivMode.U.asUInt(0, 0) // SPP is not PrivMode enum type, so asUInt and shrink the width
   out.vsstatus.bits.SIE       := in.vsstatus.SPIE
   out.vsstatus.bits.SPIE      := 1.U
+  out.vsstatus.bits.SDT       := Mux(sretToVU || sretInVS, 0.U, in.vsstatus.SDT.asBool) // clear SDT when return to VU or sret in vs
 
   out.targetPc.bits.pc        := xepc
   out.targetPc.bits.raiseIPF  := instrAddrTransType.checkPageFault(xepc)

src/main/scala/xiangshan/backend/fu/NewCSR/CSREvents/TrapEntryHSEvent.scala

@@ -15,7 +15,7 @@ import xiangshan.AddrTransType
 class TrapEntryHSEventOutput extends Bundle with EventUpdatePrivStateOutput with EventOutputBase  {
 
   // Todo: use sstatus instead of mstatus
-  val mstatus = ValidIO((new MstatusBundle ).addInEvent(_.SPP, _.SPIE, _.SIE))
+  val mstatus = ValidIO((new MstatusBundle ).addInEvent(_.SPP, _.SPIE, _.SIE, _.SDT))
   val hstatus = ValidIO((new HstatusBundle ).addInEvent(_.SPV, _.SPVP, _.GVA))
   val sepc    = ValidIO((new Epc           ).addInEvent(_.epc))
   val scause  = ValidIO((new CauseBundle   ).addInEvent(_.Interrupt, _.ExceptionCode))
@@ -124,6 +124,7 @@ class TrapEntryHSEventModule(implicit val p: Parameters) extends Module with CSR
   out.mstatus.bits.SPP          := current.privState.PRVM.asUInt(0, 0) // SPP is not PrivMode enum type, so asUInt and shrink the width
   out.mstatus.bits.SPIE         := current.sstatus.SIE
   out.mstatus.bits.SIE          := 0.U
+  out.mstatus.bits.SDT          := in.menvcfg.DTE.asBool // when DTE open set SDT to 1, else SDT is readonly 0
   // hstatus
   out.hstatus.bits.SPV          := current.privState.V
     // SPVP is not PrivMode enum type, so asUInt and shrink the width

src/main/scala/xiangshan/backend/fu/NewCSR/CSREvents/TrapEntryMEvent.scala

@@ -13,7 +13,7 @@ import xiangshan.AddrTransType
 
 class TrapEntryMEventOutput extends Bundle with EventUpdatePrivStateOutput with EventOutputBase  {
 
-  val mstatus   = ValidIO((new MstatusBundle ).addInEvent(_.MPV, _.MPP, _.GVA, _.MPIE, _.MIE))
+  val mstatus   = ValidIO((new MstatusBundle ).addInEvent(_.MPV, _.MPP, _.GVA, _.MPIE, _.MIE, _.MDT))
   val mepc      = ValidIO((new Epc           ).addInEvent(_.epc))
   val mcause    = ValidIO((new CauseBundle   ).addInEvent(_.Interrupt, _.ExceptionCode))
   val mtval     = ValidIO((new OneFieldBundle).addInEvent(_.ALL))
@@ -32,6 +32,7 @@ class TrapEntryMEventModule(implicit val p: Parameters) extends Module with CSRE
   private val satp  = current.satp
   private val vsatp = current.vsatp
   private val hgatp = current.hgatp
+  private val isDTExcp = current.hasDTExcp
 
   private val highPrioTrapNO = in.causeNO.ExceptionCode.asUInt
   private val isException = !in.causeNO.Interrupt.asBool
@@ -96,6 +97,8 @@ class TrapEntryMEventModule(implicit val p: Parameters) extends Module with CSRE
     (isLSGuestExcp                                         ) -> trapMemGPA,
   ))
 
+  private val precause = Cat(isInterrupt, highPrioTrapNO)
+
   out := DontCare
 
   out.privState.valid := valid
@@ -113,11 +116,12 @@ class TrapEntryMEventModule(implicit val p: Parameters) extends Module with CSRE
   out.mstatus.bits.GVA          := tvalFillGVA
   out.mstatus.bits.MPIE         := current.mstatus.MIE
   out.mstatus.bits.MIE          := 0.U
+  out.mstatus.bits.MDT          := 1.U
   out.mepc.bits.epc             := Mux(isFetchMalAddr, in.fetchMalTval(63, 1), trapPC(63, 1))
   out.mcause.bits.Interrupt     := isInterrupt
-  out.mcause.bits.ExceptionCode := highPrioTrapNO
+  out.mcause.bits.ExceptionCode := Mux(isDTExcp, ExceptionNO.EX_DT.U, highPrioTrapNO)
   out.mtval.bits.ALL            := Mux(isFetchMalAddr, in.fetchMalTval, tval)
-  out.mtval2.bits.ALL           := tval2 >> 2
+  out.mtval2.bits.ALL           := Mux(isDTExcp, precause, tval2 >> 2)
   out.mtinst.bits.ALL           := Mux(isFetchGuestExcp && in.trapIsForVSnonLeafPTE || isLSGuestExcp && in.memExceptionIsForVSnonLeafPTE, 0x3000.U, 0.U)
   out.targetPc.bits.pc          := in.pcFromXtvec
   out.targetPc.bits.raiseIPF    := false.B

src/main/scala/xiangshan/backend/fu/NewCSR/CSREvents/TrapEntryVSEvent.scala

@@ -14,7 +14,7 @@ import xiangshan.AddrTransType
 
 class TrapEntryVSEventOutput extends Bundle with EventUpdatePrivStateOutput with EventOutputBase  {
 
-  val vsstatus = ValidIO((new SstatusBundle ).addInEvent(_.SPP, _.SPIE, _.SIE))
+  val vsstatus = ValidIO((new SstatusBundle ).addInEvent(_.SPP, _.SPIE, _.SIE, _.SDT))
   val vsepc    = ValidIO((new Epc           ).addInEvent(_.epc))
   val vscause  = ValidIO((new CauseBundle   ).addInEvent(_.Interrupt, _.ExceptionCode))
   val vstval   = ValidIO((new OneFieldBundle).addInEvent(_.ALL))
@@ -122,6 +122,7 @@ class TrapEntryVSEventModule(implicit val p: Parameters) extends Module with CSR
   out.vsstatus.bits.SPP          := current.privState.PRVM.asUInt(0, 0) // SPP is not PrivMode enum type, so asUInt and shrink the width
   out.vsstatus.bits.SPIE         := current.vsstatus.SIE
   out.vsstatus.bits.SIE          := 0.U
+  out.vsstatus.bits.SDT          := in.henvcfg.DTE.asBool // when DTE open set SDT to 1, else SDT is readonly 0
   // SPVP is not PrivMode enum type, so asUInt and shrink the width
   out.vsepc.bits.epc             := Mux(isFetchMalAddr, in.fetchMalTval(63, 1), trapPC(63, 1))
   out.vscause.bits.Interrupt     := isInterrupt

src/main/scala/xiangshan/backend/fu/NewCSR/HypervisorLevel.scala

@@ -62,14 +62,16 @@ trait HypervisorLevel { self: NewCSR =>
     .setAddr(CSRs.hvictl)
 
   val henvcfg = Module(new CSRModule("Henvcfg", new HEnvCfg) with HasHypervisorEnvBundle {
-    when (!menvcfg.STCE.asBool) {
+    when(!menvcfg.STCE) {
       regOut.STCE := 0.U
     }
-    when (!menvcfg.PBMTE) {
+    when(!menvcfg.PBMTE) {
       regOut.PBMTE := 0.U
     }
-  })
-    .setAddr(CSRs.henvcfg)
+    when(!menvcfg.DTE) {
+      regOut.DTE := 0.U
+    }
+  }).setAddr(CSRs.henvcfg)
 
   val htval = Module(new CSRModule("Htval", new XtvalBundle) with TrapEntryHSEventSinkBundle)
     .setAddr(CSRs.htval)
@@ -340,6 +342,11 @@ class HEnvCfg extends EnvCfg {
     this.STCE.setRW().withReset(1.U)
   }
   this.PBMTE.setRW().withReset(0.U)
+  if (CSRConfig.EXT_DBLTRP) {
+    // software write envcfg to open ssdbltrp if need
+    // set 0 to pass ci
+    this.DTE.setRW().withReset(0.U)
+  }
 }
 
 trait HypervisorBundle { self: CSRModule[_] =>

src/main/scala/xiangshan/backend/fu/NewCSR/MachineLevel.scala

@@ -452,12 +452,14 @@ class MstatusBundle extends CSRBundle {
   val TVM  = CSRRWField     (20).withReset(0.U)
   val TW   = CSRRWField     (21).withReset(0.U)
   val TSR  = CSRRWField     (22).withReset(0.U)
+  val SDT  = CSRRWField     (24).withReset(0.U)
   val UXL  = XLENField      (33, 32).withReset(XLENField.XLEN64)
   val SXL  = XLENField      (35, 34).withReset(XLENField.XLEN64)
   val SBE  = CSRROField     (36).withReset(0.U)
   val MBE  = CSRROField     (37).withReset(0.U)
   val GVA  = CSRRWField     (38).withReset(0.U)
   val MPV  = VirtMode       (39).withReset(0.U)
+  val MDT  = CSRRWField     (42).withReset(mdtInit.U)
   val SD   = CSRROField     (63,
     (_, _) => FS === ContextStatus.Dirty || VS === ContextStatus.Dirty
   )
@@ -471,6 +473,7 @@ class MstatusModule(implicit override val p: Parameters) extends CSRModule("MSta
   with MNretEventSinkBundle
   with SretEventSinkBundle
   with HasRobCommitBundle
+  with HasMachineEnvBundle
 {
   val mstatus = IO(Output(bundle))
   val sstatus = IO(Output(new SstatusBundle))
@@ -496,9 +499,23 @@ class MstatusModule(implicit override val p: Parameters) extends CSRModule("MSta
     assert(reg.VS =/= ContextStatus.Off, "The [m|s]status.VS should not be Off when set dirty, please check decode")
     reg.VS := ContextStatus.Dirty
   }
-
+  // when MDT is explicitly written by 1, clear MIE
+  // only when reg.MDT is zero or wdata.MDT is zero , MIE can be explicitly written by 1
+  when (w.wdataFields.MDT && w.wen) {
+    reg.MIE := false.B
+  }
+  // when DTE is zero, SDT field is read-only zero(write any, read zero, side effect of write 1 is block)
+  val writeSDT = Wire(Bool())
+  writeSDT := Mux(this.menvcfg.DTE.asBool, (w.wdataFields.SDT && w.wen) || (wAliasSstatus.wdataFields.SDT && wAliasSstatus.wen), 0.U)
+  when (!this.menvcfg.DTE) {
+    regOut.SDT := false.B
+  }
+  // SDT and SIE is the same as MDT and MIE
+  when (writeSDT) {
+    reg.SIE := false.B
+  }
   // read connection
-  mstatus :|= reg
+  mstatus :|= regOut
   sstatus := mstatus
   rdata := mstatus.asUInt
   sstatusRdata := sstatus.asUInt
@@ -628,6 +645,11 @@ class MEnvCfg extends EnvCfg {
     this.STCE.setRW().withReset(1.U)
   }
   this.PBMTE.setRW().withReset(0.U)
+  if (CSRConfig.EXT_DBLTRP) {
+    // software write envcfg to open ssdbltrp if need
+    // set 0 to pass ci
+    this.DTE.setRW().withReset(0.U)
+  }
 }
 
 object MarchidField extends CSREnum with ROApply {