xref: /gem5/src/arch/mips/isa/formats/control.isa

// -*- mode:c++ -*-

// Copyright (c) 2007 MIPS Technologies, Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met: redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer;
// redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution;
// neither the name of the copyright holders nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Authors: Korey Sewell
//          Jaidev Patwardhan

////////////////////////////////////////////////////////////////////
//
// Coprocessor instructions
//

//Outputs to decoder.hh
output header {{

        class CP0Control : public MipsStaticInst
        {
                protected:

                /// Constructor
                CP0Control(const char *mnem, MachInst _machInst, OpClass __opClass) :
                           MipsStaticInst(mnem, _machInst, __opClass)
                {
                }

                std::string generateDisassembly(Addr pc, const SymbolTable *symtab) const;
        };
        class CP0TLB : public MipsStaticInst
        {
                protected:

                /// Constructor
                CP0TLB(const char *mnem, MachInst _machInst, OpClass __opClass) :
                           MipsStaticInst(mnem, _machInst, __opClass)
                {
                }

                std::string generateDisassembly(Addr pc, const SymbolTable *symtab) const;
        };


        class CP1Control : public MipsStaticInst
        {
                protected:

                /// Constructor
                CP1Control(const char *mnem, MachInst _machInst, OpClass __opClass) :
                           MipsStaticInst(mnem, _machInst, __opClass)
                {
                }

                std::string generateDisassembly(Addr pc, const SymbolTable *symtab) const;
        };

}};

// Basic instruction class execute method template.
def template CP0Execute {{
        Fault %(class_name)s::execute(%(CPU_exec_context)s *xc, Trace::InstRecord *traceData) const
        {
                Fault fault = NoFault;
                %(op_decl)s;
                %(op_rd)s;

                if (isCoprocessorEnabled(xc, 0)) {
                    %(code)s;
                } else {
                    fault = new CoprocessorUnusableFault(0);
                }

                if(fault == NoFault)
                {
                    %(op_wb)s;
                }
                return fault;
        }
}};

def template CP1Execute {{
        Fault %(class_name)s::execute(%(CPU_exec_context)s *xc, Trace::InstRecord *traceData) const
        {
                Fault fault = NoFault;
                %(op_decl)s;
                %(op_rd)s;

                if (isCoprocessorEnabled(xc, 1)) {
                    %(code)s;
                } else {
                    fault = new CoprocessorUnusableFault(1);
                }

                if(fault == NoFault)
                {
                    %(op_wb)s;
                }
                return fault;
        }
}};
// Basic instruction class execute method template.
def template ControlTLBExecute {{
        Fault %(class_name)s::execute(%(CPU_exec_context)s *xc, Trace::InstRecord *traceData) const
        {
                Fault fault = NoFault;
                %(op_decl)s;
                %(op_rd)s;

#if FULL_SYSTEM
                if (isCoprocessor0Enabled(xc)) {
                  if(isMMUTLB(xc)){
                      %(code)s;
                  } else {
                    fault = new ReservedInstructionFault();
                  }
                } else {
                  fault = new CoprocessorUnusableFault(0);
                }
#else // Syscall Emulation Mode - No TLB Instructions
                fault = new ReservedInstructionFault();
#endif

                if(fault == NoFault)
                {
                    %(op_wb)s;
                }
                return fault;

        }
}};

//Outputs to decoder.cc
output decoder {{
        std::string CP0Control::generateDisassembly(Addr pc, const SymbolTable *symtab) const
        {
            std::stringstream ss;
            ccprintf(ss, "%-10s r%d, %d, %d", mnemonic, RT, RD, SEL);
            return ss.str();
        }
        std::string CP0TLB::generateDisassembly(Addr pc, const SymbolTable *symtab) const
        {
            std::stringstream ss;
            ccprintf(ss, "%-10s r%d, %d, %d", mnemonic, RT, RD, SEL);
            return ss.str();
        }
        std::string CP1Control::generateDisassembly(Addr pc, const SymbolTable *symtab) const
        {
            std::stringstream ss;
            ccprintf(ss, "%-10s r%d, f%d", mnemonic, RT, FS);
            return ss.str();
        }

}};

output exec {{
        bool isCoprocessorEnabled(%(CPU_exec_context)s *xc, unsigned cop_num)
        {
#if !FULL_SYSTEM
            return true;
#else
          MiscReg Stat = xc->readMiscReg(MipsISA::Status);
          switch(cop_num)
            {
            case 0:
              {
                  MiscReg Dbg = xc->readMiscReg(MipsISA::Debug);
                  if((Stat & 0x10000006) == 0  // EXL, ERL or CU0 set, CP0 accessible
                     && (Dbg & 0x40000000) == 0 // DM bit set, CP0 accessible
                     && (Stat & 0x00000018) != 0) {  // KSU = 0, kernel mode is base mode
                      // Unable to use Status_CU0, etc directly, using bitfields & masks
                      return false;
                  }

              }
              break;
            case 1:
              if((Stat & 0x20000000) == 0) // CU1 is reset
                return false;
              break;
            case 2:
              if((Stat & 0x40000000) == 0) // CU2 is reset
                return false;
              break;
            case 3:
              if((Stat & 0x80000000) == 0) // CU3 is reset
                return false;
              break;
            default: panic("Invalid Coprocessor Number Specified");
              break;
            }
            return true;
#endif
        }
        bool inline isCoprocessor0Enabled(%(CPU_exec_context)s *xc)
        {
#if FULL_SYSTEM
          MiscReg Stat = xc->readMiscRegNoEffect(MipsISA::Status);
          MiscReg Dbg = xc->readMiscRegNoEffect(MipsISA::Debug);
          if((Stat & 0x10000006) == 0  // EXL, ERL or CU0 set, CP0 accessible
                 && (Dbg & 0x40000000) == 0 // DM bit set, CP0 accessible
                 && (Stat & 0x00000018) != 0) {  // KSU = 0, kernel mode is base mode
                // Unable to use Status_CU0, etc directly, using bitfields & masks
                  return false;
              }
#else
              //printf("Syscall Emulation Mode: CP0 Enable Check defaults to TRUE\n");
#endif
            return true;
        }
        bool isMMUTLB(%(CPU_exec_context)s *xc)
        {
#if FULL_SYSTEM
          if((xc->readMiscRegNoEffect(MipsISA::Config) & 0x00000380)==0x80)
            return true;
#endif
          return false;
        }
}};

def format CP0Control(code, *flags) {{
    flags += ('IsNonSpeculative', )
    iop = InstObjParams(name, Name, 'CP0Control', code, flags)
    header_output = BasicDeclare.subst(iop)
    decoder_output = BasicConstructor.subst(iop)
    decode_block = BasicDecode.subst(iop)
    exec_output = CP0Execute.subst(iop)
}};
def format CP0TLB(code, *flags) {{
    flags += ('IsNonSpeculative', )
    iop = InstObjParams(name, Name, 'CP0Control', code, flags)
    header_output = BasicDeclare.subst(iop)
    decoder_output = BasicConstructor.subst(iop)
    decode_block = BasicDecode.subst(iop)
    exec_output = ControlTLBExecute.subst(iop)
}};
def format CP1Control(code, *flags) {{
    flags += ('IsNonSpeculative', )
    iop = InstObjParams(name, Name, 'CP1Control', code, flags)
    header_output = BasicDeclare.subst(iop)
    decoder_output = BasicConstructor.subst(iop)
    decode_block = BasicDecode.subst(iop)
    exec_output = CP1Execute.subst(iop)
}};