PTO-ARCH-MEMORY-MODEL-FAULT-PRECISION

1// PTO-UNIT: {"id":"PTO-ARCH-MEMORY-MODEL-FAULT-PRECISION","surface":"arch","classification":["memory-model","fault-precision"],"depends_on":["PTO-ARCH-STATE-TRAP-CONTEXT"]}2func SetFaultWithCause(code: FaultCode, address: Word, cause: bits(24))3begin4    let source_ring = CurrentACR();5    let ring = if code == Fault_None then source_ring6        else TrapTargetForFault(source_ring);7    if code != Fault_None then8        SaveTrapContext(ring, source_ring);9    end;10    _LastFault = code;11    _FaultAddress = address;12    _ACRTrapAsynchronous[[ring]] = FALSE;13    _ACRTrapArgumentValid[[ring]] = code != Fault_None;14    _ACRTrapCause[[ring]] = cause;15    case code of16        when Fault_None => _ACRTrapNumber[[ring]] = Zeros{6};17        when Fault_ExecutionStateCheck => _ACRTrapNumber[[ring]] = Zeros{6};18        when Fault_IllegalInstruction => _ACRTrapNumber[[ring]] = Zeros{6} + 4;19        when Fault_InstructionPC => _ACRTrapNumber[[ring]] = Zeros{6} + 32;20        when Fault_InstructionPage => _ACRTrapNumber[[ring]] = Zeros{6} + 33;21        when Fault_DataAlignment => _ACRTrapNumber[[ring]] = Zeros{6} + 34;22        when Fault_DataPage => _ACRTrapNumber[[ring]] = Zeros{6} + 35;23        when Fault_HardwareBreakpoint => _ACRTrapNumber[[ring]] = Zeros{6} + 49;24        when Fault_SoftwareBreakpoint => _ACRTrapNumber[[ring]] = Zeros{6} + 50;25        when Fault_HardwareWatchpoint => _ACRTrapNumber[[ring]] = Zeros{6} + 51;26        when Fault_Assert => _ACRTrapNumber[[ring]] = Zeros{6} + 52;27        when Fault_TileLegality => _ACRTrapNumber[[ring]] = Zeros{6} + 5;28        when Fault_TileAllocation => _ACRTrapNumber[[ring]] = Zeros{6} + 5;29        when Fault_BundleControl => _ACRTrapNumber[[ring]] = Zeros{6} + 5;30        // B.CATR.trap is a successful-commit boundary trap, not a failed31        // instruction.  It uses the bundle exception class while preserving32        // the already selected continuation in the saved clean context.33        when Fault_BundlePostCommit => _ACRTrapNumber[[ring]] = Zeros{6} + 5;34        when Fault_ServiceRequest => _ACRTrapNumber[[ring]] = Zeros{6} + 6;35    end;36    _ACRTrapArgument0[[ring]] = address;37    if code != Fault_None then38        SetCurrentACR(ring);39        WriteTPC(TrapVectorEntry(ring, address));40    end;41end;42
43func SetFault(code: FaultCode, address: Word)44begin45    SetFaultWithCause(code, address, Zeros{24});46end;47
48func RaiseServiceRequest(request_type: bits(4)) => boolean49begin50    let source_ring = CurrentACR();51    if !ServiceRequestPermitted(source_ring, request_type) then52        SetFault(Fault_IllegalInstruction, ReadTPC());53        return FALSE;54    end;55
56    let source_tpc = ReadTPC();57    let resume_tpc = source_tpc + (Zeros{PTO_XLEN} + 4);58    let target_ring = ServiceRequestTarget(source_ring, request_type);59    SaveTrapContext(target_ring, source_ring);60    _TrapContexts[[target_ring]].tpc = resume_tpc;61    let ebarg_tpc_index = ((target_ring * 4096) + 0x0f43)62        as SystemRegisterFileIndex;63    _ExtendedSystemRegisters[[ebarg_tpc_index]] = resume_tpc;64
65    _LastFault = Fault_ServiceRequest;66    _FaultAddress = source_tpc;67    _ACRTrapAsynchronous[[target_ring]] = FALSE;68    _ACRTrapArgumentValid[[target_ring]] = TRUE;69    _ACRTrapCause[[target_ring]] = ZeroExtend{24}(request_type);70    _ACRTrapNumber[[target_ring]] = Zeros{6} + 6;71    _ACRTrapArgument0[[target_ring]] = source_tpc;72    SetCurrentACR(target_ring);73    WriteTPC(TrapVectorEntry(target_ring, source_tpc));74    return TRUE;75end;76
77func ClearFault()78begin79    let ring = CurrentACR();80    _LastFault = Fault_None;81    _FaultAddress = Zeros{PTO_XLEN};82    _ACRTrapAsynchronous[[ring]] = FALSE;83    _ACRTrapArgumentValid[[ring]] = FALSE;84    _ACRTrapCause[[ring]] = Zeros{24};85    _ACRTrapNumber[[ring]] = Zeros{6};86    _ACRTrapArgument0[[ring]] = Zeros{PTO_XLEN};87end;88
89func RaiseInterrupt(interrupt_id: InterruptID, cause: bits(24))90begin91    let source_ring = CurrentACR();92    let ring = TrapTargetForInterrupt(source_ring);93    SetInterruptPending(ring, interrupt_id);94    if !InterruptEnabled(ring, interrupt_id) then return; end;95    SaveTrapContext(ring, source_ring);96    _LastFault = Fault_None;97    _FaultAddress = Zeros{PTO_XLEN};98    _ACRTrapAsynchronous[[ring]] = TRUE;99    _ACRTrapArgumentValid[[ring]] = TRUE;100    _ACRTrapCause[[ring]] = cause;101    _ACRTrapNumber[[ring]] = Zeros{6} + 44;102    _ACRTrapArgument0[[ring]] =103        NaturalToWord(interrupt_id as integer {0..262144});104    SetCurrentACR(ring);105    WriteTPC(TrapVectorEntry(ring, ReadTPC()));106end;107
108readonly func PackTrapStatus(ring: AccessControlRing) => Word109begin110    var value: Word = Zeros{PTO_XLEN};111    value[63] = if _ACRTrapAsynchronous[[ring]] then '1' else '0';112    value[62] = if _ACRTrapArgumentValid[[ring]] then '1' else '0';113    value[24 +: 24] = _ACRTrapCause[[ring]];114    value[0 +: 6] = _ACRTrapNumber[[ring]];115    return value;116end;117
118func UnpackTrapStatus(ring: AccessControlRing, value: Word)119begin120    _ACRTrapAsynchronous[[ring]] = value[63] == '1';121    _ACRTrapArgumentValid[[ring]] = value[62] == '1';122    _ACRTrapCause[[ring]] = value[24 +: 24];123    _ACRTrapNumber[[ring]] = value[0 +: 6];124end;125