/*
 * Copyright (c) 2019, 2022 ARM Limited
 * All rights reserved
 *
 * The license below extends only to copyright in the software and shall
 * not be construed as granting a license to any other intellectual
 * property including but not limited to intellectual property relating
 * to a hardware implementation of the functionality of the software
 * licensed hereunder.  You may use the software subject to the license
 * terms below provided that you ensure that this notice is replicated
 * unmodified and in its entirety in all distributions of the software,
 * modified or unmodified, in source code or in binary form.
 *
 * Copyright (c) 2018 Metempsy Technology Consulting
 * 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 __DEV_ARM_GICV3_CPU_INTERFACE_H__
#define __DEV_ARM_GICV3_CPU_INTERFACE_H__

#include "arch/arm/isa_device.hh"
#include "dev/arm/gic_v3.hh"

namespace gem5
{

class Gicv3Distributor;
class Gicv3Redistributor;

namespace ArmISA
{
class ISA;
}

class Gicv3CPUInterface : public ArmISA::BaseISADevice, public Serializable
{
  private:

    friend class Gicv3Distributor;
    friend class Gicv3Redistributor;
    friend class ArmISA::ISA;

  protected:

    Gicv3 * gic;
    Gicv3Redistributor * redistributor;
    Gicv3Distributor * distributor;
    uint32_t cpuId;

    ArmInterruptPin *maintenanceInterrupt;

    BitUnion64(ICC_CTLR_EL1)
        Bitfield<63, 20> res0_3;
        Bitfield<19>     ExtRange;
        Bitfield<18>     RSS;
        Bitfield<17, 16> res0_2;
        Bitfield<15>     A3V;
        Bitfield<14>     SEIS;
        Bitfield<13, 11> IDbits;
        Bitfield<10, 8>  PRIbits;
        Bitfield<7>      res0_1;
        Bitfield<6>      PMHE;
        Bitfield<5, 2>   res0_0;
        Bitfield<1>      EOImode;
        Bitfield<0>      CBPR;
    EndBitUnion(ICC_CTLR_EL1)

    BitUnion64(ICC_CTLR_EL3)
        Bitfield<63, 20> res0_2;
        Bitfield<19>     ExtRange;
        Bitfield<18>     RSS;
        Bitfield<17>     nDS;
        Bitfield<16>     res0_1;
        Bitfield<15>     A3V;
        Bitfield<14>     SEIS;
        Bitfield<13, 11> IDbits;
        Bitfield<10, 8>  PRIbits;
        Bitfield<7>      res0_0;
        Bitfield<6>      PMHE;
        Bitfield<5>      RM;
        Bitfield<4>      EOImode_EL1NS;
        Bitfield<3>      EOImode_EL1S;
        Bitfield<2>      EOImode_EL3;
        Bitfield<1>      CBPR_EL1NS;
        Bitfield<0>      CBPR_EL1S;
    EndBitUnion(ICC_CTLR_EL3)

    BitUnion64(ICC_IGRPEN0_EL1)
        Bitfield<63, 1> res0;
        Bitfield<0>     Enable;
    EndBitUnion(ICC_IGRPEN0_EL1)

    BitUnion64(ICC_IGRPEN1_EL1)
        Bitfield<63, 1> res0;
        Bitfield<0>     Enable;
    EndBitUnion(ICC_IGRPEN1_EL1)

    BitUnion64(ICC_IGRPEN1_EL3)
        Bitfield<63, 2> res0;
        Bitfield<1>     EnableGrp1S;
        Bitfield<0>     EnableGrp1NS;
    EndBitUnion(ICC_IGRPEN1_EL3)

    BitUnion64(ICC_SRE_EL1)
        Bitfield<63, 3> res0;
        Bitfield<2>     DIB;
        Bitfield<1>     DFB;
        Bitfield<0>     SRE;
    EndBitUnion(ICC_SRE_EL1)

    BitUnion64(ICC_SRE_EL2)
        Bitfield<63, 4> res0;
        Bitfield<3>     Enable;
        Bitfield<2>     DIB;
        Bitfield<1>     DFB;
        Bitfield<0>     SRE;
    EndBitUnion(ICC_SRE_EL2)

    BitUnion64(ICC_SRE_EL3)
        Bitfield<63, 4> res0;
        Bitfield<3>     Enable;
        Bitfield<2>     DIB;
        Bitfield<1>     DFB;
        Bitfield<0>     SRE;
    EndBitUnion(ICC_SRE_EL3)

    static const uint8_t PRIORITY_BITS = 5;

    // Minimum BPR for Secure, or when security not enabled
    static const uint8_t GIC_MIN_BPR = 2;
    //  Minimum BPR for Nonsecure when security is enabled
    static const uint8_t GIC_MIN_BPR_NS = GIC_MIN_BPR + 1;

    static const uint8_t VIRTUAL_PRIORITY_BITS   = 5;
    static const uint8_t VIRTUAL_PREEMPTION_BITS = 5;
    static const uint8_t VIRTUAL_NUM_LIST_REGS   = 16;

    static const uint8_t GIC_MIN_VBPR = 7 - VIRTUAL_PREEMPTION_BITS;

    struct hppi_t
    {
        uint32_t intid;
        uint8_t prio;
        Gicv3::GroupId group;
    };

    hppi_t hppi;

    // GIC CPU interface memory mapped control registers (legacy)
    enum
    {
        GICC_CTLR    = 0x0000,
        GICC_PMR     = 0x0004,
        GICC_BPR     = 0x0008,
        GICC_IAR     = 0x000C,
        GICC_EOIR    = 0x0010,
        GICC_RPR     = 0x0014,
        GICC_HPPI    = 0x0018,
        GICC_ABPR    = 0x001C,
        GICC_AIAR    = 0x0020,
        GICC_AEOIR   = 0x0024,
        GICC_AHPPIR  = 0x0028,
        GICC_STATUSR = 0x002C,
        GICC_IIDR    = 0x00FC,
    };

    static const AddrRange GICC_APR;
    static const AddrRange GICC_NSAPR;

    // GIC CPU virtual interface memory mapped control registers (legacy)
    enum
    {
        GICH_HCR   = 0x0000,
        GICH_VTR   = 0x0004,
        GICH_VMCR  = 0x0008,
        GICH_MISR  = 0x0010,
        GICH_EISR  = 0x0020,
        GICH_ELRSR = 0x0030,
    };

    static const AddrRange GICH_APR;
    static const AddrRange GICH_LR;

  public:
    BitUnion64(ICH_HCR_EL2)
        Bitfield<63, 32> res0_2;
        Bitfield<31, 27> EOIcount;
        Bitfield<26, 15> res0_1;
        Bitfield<14>     TDIR;
        Bitfield<13>     TSEI;
        Bitfield<12>     TALL1;
        Bitfield<11>     TALL0;
        Bitfield<10>     TC;
        Bitfield<9, 8>   res0_0;
        Bitfield<7>      VGrp1DIE;
        Bitfield<6>      VGrp1EIE;
        Bitfield<5>      VGrp0DIE;
        Bitfield<4>      VGrp0EIE;
        Bitfield<3>      NPIE;
        Bitfield<2>      LRENPIE;
        Bitfield<1>      UIE;
        Bitfield<0>      En;
    EndBitUnion(ICH_HCR_EL2)

  protected:
    BitUnion64(ICH_LR_EL2)
        Bitfield<63, 62> State;
        Bitfield<61>     HW;
        Bitfield<60>     Group;
        Bitfield<59, 56> res0_1;
        Bitfield<55, 48> Priority;
        Bitfield<47, 45> res0_0;
        Bitfield<44, 32> pINTID;
        Bitfield<41>     EOI;
        Bitfield<31, 0>  vINTID;
    EndBitUnion(ICH_LR_EL2)

    static const uint64_t ICH_LR_EL2_STATE_INVALID        = 0;
    static const uint64_t ICH_LR_EL2_STATE_PENDING        = 1;
    static const uint64_t ICH_LR_EL2_STATE_ACTIVE         = 2;
    static const uint64_t ICH_LR_EL2_STATE_ACTIVE_PENDING = 3;

    BitUnion32(ICH_LRC)
        Bitfield<31, 30> State;
        Bitfield<29>     HW;
        Bitfield<28>     Group;
        Bitfield<27, 24> res0_1;
        Bitfield<23, 16> Priority;
        Bitfield<15, 13> res0_0;
        Bitfield<12, 0>  pINTID;
        Bitfield<9>      EOI;
    EndBitUnion(ICH_LRC)

    BitUnion64(ICH_MISR_EL2)
        Bitfield<63, 8> res0;
        Bitfield<7>     VGrp1D;
        Bitfield<6>     VGrp1E;
        Bitfield<5>     VGrp0D;
        Bitfield<4>     VGrp0E;
        Bitfield<3>     NP;
        Bitfield<2>     LRENP;
        Bitfield<1>     U;
        Bitfield<0>     EOI;
    EndBitUnion(ICH_MISR_EL2)

    BitUnion64(ICH_VMCR_EL2)
        Bitfield<63, 32> res0_2;
        Bitfield<31, 24> VPMR;
        Bitfield<23, 21> VBPR0;
        Bitfield<20, 18> VBPR1;
        Bitfield<17, 10> res0_1;
        Bitfield<9>      VEOIM;
        Bitfield<8, 5>   res0_0;
        Bitfield<4>      VCBPR;
        Bitfield<3>      VFIQEn;
        Bitfield<2>      VAckCtl;
        Bitfield<1>      VENG1;
        Bitfield<0>      VENG0;
    EndBitUnion(ICH_VMCR_EL2)

    BitUnion64(ICH_VTR_EL2)
        Bitfield<63, 32> res0_1;
        Bitfield<31, 29> PRIbits;
        Bitfield<28, 26> PREbits;
        Bitfield<25, 23> IDbits;
        Bitfield<22>     SEIS;
        Bitfield<21>     A3V;
        Bitfield<20>     res1;
        Bitfield<19>     TDS;
        Bitfield<18, 5>  res0_0;
        Bitfield<4, 0>   ListRegs;
    EndBitUnion(ICH_VTR_EL2)

    BitUnion64(ICV_CTLR_EL1)
        Bitfield<63, 19> res0_2;
        Bitfield<18>     RSS;
        Bitfield<17, 16> res0_1;
        Bitfield<15>     A3V;
        Bitfield<14>     SEIS;
        Bitfield<13, 11> IDbits;
        Bitfield<10, 8>  PRIbits;
        Bitfield<7, 2>   res0_0;
        Bitfield<1>      EOImode;
        Bitfield<0>      CBPR;
    EndBitUnion(ICV_CTLR_EL1)

  protected:

    void activateIRQ(uint32_t intid, Gicv3::GroupId group);
    void generateSGI(RegVal val, Gicv3::GroupId group);
    ArmISA::ExceptionLevel currEL() const;
    void deactivateIRQ(uint32_t intid, Gicv3::GroupId group);
    void dropPriority(Gicv3::GroupId group);
    uint64_t eoiMaintenanceInterruptStatus() const;
    bool getHCREL2FMO() const;
    bool getHCREL2IMO() const;
    uint32_t getHPPIR0() const;
    uint32_t getHPPIR1() const;
    int getHPPVILR() const;
    bool groupEnabled(Gicv3::GroupId group) const;
    uint32_t groupPriorityMask(Gicv3::GroupId group);
    bool haveEL(ArmISA::ExceptionLevel el) const;
    int highestActiveGroup() const;
    uint8_t highestActivePriority() const;
    bool hppiCanPreempt();
    bool hppviCanPreempt(int lrIdx) const;
    bool inSecureState() const;
    ArmISA::InterruptTypes intSignalType(Gicv3::GroupId group) const;
    bool isAA64() const;
    bool isEL3OrMon() const;
    bool isEOISplitMode() const;
    bool isSecureBelowEL3() const;
    ICH_MISR_EL2 maintenanceInterruptStatus() const;
    void resetHppi(uint32_t intid);
    void serialize(CheckpointOut & cp) const override;
    void unserialize(CheckpointIn & cp) override;
    void update();
    void updateDistributor();
    void virtualActivateIRQ(uint32_t lrIdx);
    void virtualDeactivateIRQ(int lrIdx);
    uint8_t virtualDropPriority();
    int virtualFindActive(uint32_t intid) const;
    uint32_t virtualGroupPriorityMask(Gicv3::GroupId group) const;
    uint8_t virtualHighestActivePriority() const;
    void virtualIncrementEOICount();
    bool virtualIsEOISplitMode() const;
    void virtualUpdate();
    RegVal bpr1(Gicv3::GroupId group);
    bool havePendingInterrupts(void) const;
    void clearPendingInterrupts(void);
    void assertWakeRequest(void);
    void deassertWakeRequest(void);

    RegVal readBankedMiscReg(ArmISA::MiscRegIndex misc_reg) const;
    void setBankedMiscReg(ArmISA::MiscRegIndex misc_reg, RegVal val) const;
  public:

    Gicv3CPUInterface(Gicv3 * gic, uint32_t cpu_id);

    void init();

  public:
    void copy(Gicv3Registers *from, Gicv3Registers *to);

  public: // BaseISADevice
    RegVal readMiscReg(int misc_reg) override;
    void setMiscReg(int misc_reg, RegVal val) override;
    void setThreadContext(ThreadContext *tc) override;
};

} // namespace gem5

#endif //__DEV_ARM_GICV3_CPU_INTERFACE_H__