isa.hh

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/*
 * Copyright (c) 2009 The Regents of The University of Michigan
 * Copyright (c) 2009 The University of Edinburgh
 * Copyright (c) 2014 Sven Karlsson
 * Copyright (c) 2016 RISC-V Foundation
 * Copyright (c) 2016 The University of Virginia
 * Copyright (c) 2020 Barkhausen Institut
 * Coypright (c) 2024 University of Rostock
 * 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,
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 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
#ifndef __ARCH_RISCV_ISA_HH__
#define __ARCH_RISCV_ISA_HH__
 
#include <string>
#include <unordered_map>
#include <vector>
 
#include "arch/generic/isa.hh"
#include "arch/riscv/pcstate.hh"
#include "arch/riscv/regs/misc.hh"
#include "arch/riscv/types.hh"
#include "base/types.hh"
 
namespace gem5
{
 
struct RiscvISAParams;
class Checkpoint;
 
namespace RiscvISA
{
 
enum PrivilegeMode
{
    PRV_U = 0,
    PRV_S = 1,
    // NEVER SET prv = PRV_HS!
    PRV_HS = 2, // H-extension
    PRV_M = 3
};
 
enum FPUStatus
{
    OFF = 0,
    INITIAL = 1,
    CLEAN = 2,
    DIRTY = 3,
};
 
using VPUStatus = FPUStatus;
 
class ISA : public BaseISA
{
  protected:
    RiscvType _rvType;
    std::vector<RegVal> miscRegFile;
    bool enableRvv;
 
    bool hpmCounterEnabled(int counter) const;
 
    // Load reserve - store conditional monitor
    const int WARN_FAILURE = 10000;
    const Addr INVALID_RESERVATION_ADDR = (Addr)-1;
    std::unordered_map<int, Addr> load_reservation_addrs;

    unsigned vlen;

    unsigned elen;

    PrivilegeModeSet _privilegeModeSet;

    const bool _wfiResumeOnPending;

    bool _enableZcd;

    bool _enableSmrnmi;
 
  public:
    using Params = RiscvISAParams;
 
    void clear() override;
 
    PCStateBase*
    newPCState(Addr new_inst_addr=0) const override
    {
        return new PCState(rvSext(new_inst_addr), _rvType);
    }
 
  public:
    RegVal readMiscRegNoEffect(RegIndex idx) const override;
    RegVal readMiscReg(RegIndex idx) override;
    void setMiscRegNoEffect(RegIndex idx, RegVal val) override;
    void setMiscReg(RegIndex idx, RegVal val) override;
 
    // Derived class could provide knowledge of non-standard CSRs to other
    // components by overriding the two getCSRxxxMap here and properly
    // implementing the corresponding read/set function. However, customized
    // maps should always be compatible with the standard maps.
    virtual const std::unordered_map<int, CSRMetadata>&
    getCSRDataMap() const
    {
        return CSRData;
    }
    virtual const std::unordered_map<int, RegVal>&
    getCSRMaskMap() const
    {
        return CSRMasks[_rvType][_privilegeModeSet];
    }
 
    virtual const std::unordered_map<int, RegVal>&
    getCSRWriteMaskMap() const
    {
        return CSRWriteMasks[_rvType][_privilegeModeSet];
    }
 
    bool inUserMode() const override;
    void copyRegsFrom(ThreadContext *src) override;
 
    void serialize(CheckpointOut &cp) const override;
    void unserialize(CheckpointIn &cp) override;
 
    ISA(const Params &p);
 
    void handleLockedRead(const RequestPtr &req) override;
 
    bool handleLockedWrite(const RequestPtr &req,
            Addr cacheBlockMask) override;
 
    void handleLockedSnoop(PacketPtr pkt, Addr cacheBlockMask) override;
 
    void globalClearExclusive() override;
 
    void resetThread() override;
 
    RiscvType rvType() const { return _rvType; }
 
    bool getEnableRvv() const { return enableRvv; }
 
    bool virtualizationEnabled() const;
 
    void
    clearLoadReservation(ContextID cid)
    {
        Addr& load_reservation_addr = load_reservation_addrs[cid];
        load_reservation_addr = INVALID_RESERVATION_ADDR;
    }

    unsigned getVecLenInBits() { return vlen; }
    unsigned getVecLenInBytes() { return vlen >> 3; }
    unsigned getVecElemLenInBits() { return elen; }
 
    int64_t getVectorLengthInBytes() const override { return vlen >> 3; }
 
    PrivilegeModeSet getPrivilegeModeSet() { return _privilegeModeSet; }
 
    bool resumeOnPending() { return _wfiResumeOnPending; }
 
    bool enableZcd() { return _enableZcd; }
 
    bool enableSmrnmi() { return _enableSmrnmi; }
 
    virtual Addr getFaultHandlerAddr(
        RegIndex idx, uint64_t cause, bool intr) const;
 
    Addr rvSext(Addr addr) const
    {
        return (_rvType == RV32) ? sext<32>(addr) : addr;
    }
 
    void swapToVirtCSR(uint64_t& csr, RegIndex& midx, std::string& csrName);
 
    Fault hpmCounterCheck(int counter, ExtMachInst machInst) const;
    Fault tvmChecks(uint64_t csr, PrivilegeMode pm, ExtMachInst machInst);
 
    RegVal backdoorReadCSRAllBits(ExecContext *xc, uint64_t csr);
    RegVal readCSR(ExecContext *xc, uint64_t csr);
    void writeCSR(ExecContext *xc, uint64_t csr, RegVal writeData);
};
 
// V-bit utilities (H-extension)
 
bool virtualizationEnabled(ExecContext *xc);
bool virtualizationEnabled(ThreadContext *tc);
 
void setV(ExecContext *xc);
void setV(ThreadContext *tc);
 
void resetV(ExecContext *xc);
void resetV(ThreadContext *tc);
 
Fault updateFPUStatus(
    ExecContext *xc, ExtMachInst machInst, bool set_dirty);
 
Fault updateVPUStatus(
    ExecContext *xc, ExtMachInst machInst, bool set_dirty, bool check_vill);
 
} // namespace RiscvISA
} // namespace gem5
 
std::ostream &operator<<(std::ostream &os, gem5::RiscvISA::PrivilegeMode pm);
 
#endif // __ARCH_RISCV_ISA_HH__