gic_v2.hh

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/*
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 * 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
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 * Copyright (c) 2005 The Regents of The University of Michigan
 * All rights reserved.
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 * met: redistributions of source code must retain the above copyright
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#ifndef __DEV_ARM_GICV2_H__
#define __DEV_ARM_GICV2_H__
 
#include <vector>
 
#include "arch/arm/interrupts.hh"
#include "base/addr_range.hh"
#include "base/bitunion.hh"
#include "dev/arm/base_gic.hh"
#include "dev/io_device.hh"
#include "dev/platform.hh"
 
namespace gem5
{
 
struct GicV2Params;
 
class GicV2Registers
{
  public:
    virtual ~GicV2Registers() = default;
    virtual uint32_t readDistributor(ContextID ctx, Addr daddr) = 0;
    virtual uint32_t readCpu(ContextID ctx, Addr daddr) = 0;
 
    virtual void writeDistributor(ContextID ctx, Addr daddr,
                                  uint32_t data) = 0;
    virtual void writeCpu(ContextID ctx, Addr daddr, uint32_t data) = 0;
 
  protected:
    static void copyDistRegister(GicV2Registers* from,
                                 GicV2Registers* to,
                                 ContextID ctx, Addr daddr);
    static void copyCpuRegister(GicV2Registers* from,
                                GicV2Registers* to,
                                ContextID ctx, Addr daddr);
    static void copyBankedDistRange(System *sys,
                                    GicV2Registers* from,
                                    GicV2Registers* to,
                                    Addr daddr, size_t size);
    static void clearBankedDistRange(System *sys, GicV2Registers* to,
                                     Addr daddr, size_t size);
    static void copyDistRange(GicV2Registers* from,
                              GicV2Registers* to,
                              Addr daddr, size_t size);
    static void clearDistRange(GicV2Registers* to, Addr daddr, size_t size);
};
 
class GicV2 : public BaseGic, public GicV2Registers
{
  protected:
    // distributor memory addresses
    enum
    {
        GICD_CTLR          = 0x000, // control register
        GICD_TYPER         = 0x004, // controller type
        GICD_IIDR          = 0x008, // implementer id
        GICD_SGIR          = 0xf00, // software generated interrupt
        GICD_PIDR0         = 0xfe0, // distributor peripheral ID0
        GICD_PIDR1         = 0xfe4, // distributor peripheral ID1
        GICD_PIDR2         = 0xfe8, // distributor peripheral ID2
        GICD_PIDR3         = 0xfec, // distributor peripheral ID3
 
        DIST_SIZE          = 0x1000,
    };
 
    const uint32_t gicdPIDR;
    const uint32_t gicdIIDR;
    const uint32_t giccIIDR;
 
    static const AddrRange GICD_IGROUPR;    // interrupt group (unimplemented)
    static const AddrRange GICD_ISENABLER;  // interrupt set enable
    static const AddrRange GICD_ICENABLER;  // interrupt clear enable
    static const AddrRange GICD_ISPENDR;    // set pending interrupt
    static const AddrRange GICD_ICPENDR;    // clear pending interrupt
    static const AddrRange GICD_ISACTIVER;  // active bit registers
    static const AddrRange GICD_ICACTIVER;  // clear bit registers
    static const AddrRange GICD_IPRIORITYR; // interrupt priority registers
    static const AddrRange GICD_ITARGETSR;  // processor target registers
    static const AddrRange GICD_ICFGR;      // interrupt config registers
 
    // cpu memory addresses
    enum
    {
        GICC_CTLR  = 0x00, // CPU control register
        GICC_PMR   = 0x04, // Interrupt priority mask
        GICC_BPR   = 0x08, // binary point register
        GICC_IAR   = 0x0C, // interrupt ack register
        GICC_EOIR  = 0x10, // end of interrupt
        GICC_RPR   = 0x14, // running priority
        GICC_HPPIR = 0x18, // highest pending interrupt
        GICC_ABPR  = 0x1c, // aliased binary point
        GICC_APR0  = 0xd0, // active priority register 0
        GICC_APR1  = 0xd4, // active priority register 1
        GICC_APR2  = 0xd8, // active priority register 2
        GICC_APR3  = 0xdc, // active priority register 3
        GICC_IIDR  = 0xfc, // cpu interface id register
        GICC_DIR   = 0x1000, // deactive interrupt register
    };
 
    static const int SGI_MAX = 16;  // Number of Software Gen Interrupts
    static const int PPI_MAX = 16;  // Number of Private Peripheral Interrupts

    static const int SGI_MASK = 0xFFFF0000;

    static const int NN_CONFIG_MASK = 0x55555555;
 
    static const int CPU_MAX = 256;   // Max number of supported CPU interfaces
    static const int SPURIOUS_INT = 1023;
    static const int INT_BITS_MAX = 32;
    static const int INT_LINES_MAX = 1020;
    static const int GLOBAL_INT_LINES = INT_LINES_MAX - SGI_MAX - PPI_MAX;

    static const int GICC_BPR_MINIMUM = 2;
 
    BitUnion32(SWI)
        Bitfield<3,0> sgi_id;
        Bitfield<23,16> cpu_list;
        Bitfield<25,24> list_type;
    EndBitUnion(SWI)
 
    BitUnion32(IAR)
        Bitfield<9,0> ack_id;
        Bitfield<12,10> cpu_id;
    EndBitUnion(IAR)
 
    BitUnion32(CTLR)
        Bitfield<3> fiqEn;
        Bitfield<1> enableGrp1;
        Bitfield<0> enableGrp0;
    EndBitUnion(CTLR)
 
  protected: /* Params */
    const AddrRange distRange;

    const AddrRange cpuRange;

    const AddrRangeList addrRanges;

    const Tick distPioDelay;

    const Tick cpuPioDelay;

    const Tick intLatency;
 
  protected:
    bool enabled;

    const bool haveGem5Extensions;

    bool gem5ExtensionsEnabled;

    uint32_t itLines;

    struct BankedRegs : public Serializable
    {
        uint32_t intEnabled;

        uint32_t pendingInt;

        uint32_t activeInt;

        uint32_t intGroup;

        uint32_t intConfig[2];

        uint8_t intPriority[SGI_MAX + PPI_MAX];
 
        void serialize(CheckpointOut &cp) const override;
        void unserialize(CheckpointIn &cp) override;
 
        BankedRegs() :
            intEnabled(0), pendingInt(0), activeInt(0),
            intGroup(0), intConfig {0}, intPriority {0}
          {}
    };
    std::vector<BankedRegs*> bankedRegs;
 
    BankedRegs& getBankedRegs(ContextID);

    uint32_t intEnabled[INT_BITS_MAX-1];
 
    uint32_t&
    getIntEnabled(ContextID ctx, uint32_t ix)
    {
        if (ix == 0) {
            return getBankedRegs(ctx).intEnabled;
        } else {
            return intEnabled[ix - 1];
        }
    }

    uint32_t pendingInt[INT_BITS_MAX-1];
 
    uint32_t&
    getPendingInt(ContextID ctx, uint32_t ix)
    {
        assert(ix < INT_BITS_MAX);
        if (ix == 0) {
            return getBankedRegs(ctx).pendingInt;
        } else {
            return pendingInt[ix - 1];
        }
    }

    uint32_t activeInt[INT_BITS_MAX-1];
 
    uint32_t&
    getActiveInt(ContextID ctx, uint32_t ix)
    {
        assert(ix < INT_BITS_MAX);
        if (ix == 0) {
            return getBankedRegs(ctx).activeInt;
        } else {
            return activeInt[ix - 1];
        }
    }

    uint32_t intGroup[INT_BITS_MAX-1];
 
    uint32_t&
    getIntGroup(ContextID ctx, uint32_t ix)
    {
        assert(ix < INT_BITS_MAX);
        if (ix == 0) {
            return getBankedRegs(ctx).intGroup;
        } else {
            return intGroup[ix - 1];
        }
    }

    uint32_t iccrpr[CPU_MAX];

    uint8_t intPriority[GLOBAL_INT_LINES];
 
    uint8_t&
    getIntPriority(ContextID ctx, uint32_t ix)
    {
        assert(ix < INT_LINES_MAX);
        if (ix < SGI_MAX + PPI_MAX) {
            return getBankedRegs(ctx).intPriority[ix];
        } else {
            return intPriority[ix - (SGI_MAX + PPI_MAX)];
        }
    }

    uint32_t intConfig[INT_BITS_MAX*2 - 2];

    uint32_t&
    getIntConfig(ContextID ctx, uint32_t ix)
    {
        assert(ix < INT_BITS_MAX*2);
        if (ix < 2) {
            return getBankedRegs(ctx).intConfig[ix];
        } else {
            return intConfig[ix - 2];
        }
    }

    uint8_t cpuTarget[GLOBAL_INT_LINES];
 
    uint8_t
    getCpuTarget(ContextID ctx, uint32_t ix) const
    {
        assert(ctx < sys->threads.numRunning());
        assert(ix < INT_LINES_MAX);
        if (ix < SGI_MAX + PPI_MAX) {
            // "GICD_ITARGETSR0 to GICD_ITARGETSR7 are read-only, and each
            // field returns a value that corresponds only to the processor
            // reading the register."
            uint32_t ctx_mask;
            if (gem5ExtensionsEnabled) {
                ctx_mask = ctx;
            } else {
                fatal_if(ctx >= 8,
                    "%s requires the gem5_extensions parameter to support "
                    "more than 8 cores\n", name());
                // convert the CPU id number into a bit mask
                ctx_mask = 1 << ctx;
            }
            return ctx_mask;
        } else {
            return cpuTarget[ix - 32];
        }
    }
 
    bool
    isLevelSensitive(ContextID ctx, uint32_t int_num)
    {
        if (int_num == SPURIOUS_INT) {
            return false;
        } else {
            const auto ix = intNumToWord(int_num * 2);
            const uint8_t cfg_hi = intNumToBit(int_num * 2) + 1;
            return bits(getIntConfig(ctx, ix), cfg_hi) == 0;
        }
    }
 
    bool
    isGroup0(ContextID ctx, uint32_t int_num)
    {
        const uint32_t group_reg = getIntGroup(ctx, intNumToWord(int_num));
        return !bits(group_reg, intNumToBit(int_num));
    }

    bool
    isFiq(ContextID ctx, uint32_t int_num)
    {
        const bool is_group0 = isGroup0(ctx, int_num);
        const bool use_fiq = cpuControl[ctx].fiqEn;
 
        if (is_group0 && use_fiq) {
            return true;
        } else {
            return false;
        }
    }

    bool
    cpuEnabled(ContextID ctx) const
    {
        return cpuControl[ctx].enableGrp0 ||
               cpuControl[ctx].enableGrp1;
    }

    CTLR cpuControl[CPU_MAX];

    uint8_t cpuPriority[CPU_MAX];
    uint8_t getCpuPriority(unsigned cpu); // BPR-adjusted priority value

    uint8_t cpuBpr[CPU_MAX];

    uint32_t cpuHighestInt[CPU_MAX];

    uint64_t cpuSgiPending[SGI_MAX];
    uint64_t cpuSgiActive[SGI_MAX];

    uint32_t cpuSgiPendingExt[CPU_MAX];
    uint32_t cpuSgiActiveExt[CPU_MAX];

    uint32_t cpuPpiPending[CPU_MAX];
    uint32_t cpuPpiActive[CPU_MAX];

    void softInt(ContextID ctx, SWI swi);

    void updateIntState(int hint);

    void updateRunPri();

    uint64_t genSwiMask(int cpu);
 
    int intNumToWord(int num) const { return num >> 5; }
    int intNumToBit(int num) const { return num % 32; }

    void clearInt(ContextID ctx, uint32_t int_num);

    void postInt(uint32_t cpu, Tick when);
    void postFiq(uint32_t cpu, Tick when);

    void postDelayedInt(uint32_t cpu);
    void postDelayedFiq(uint32_t cpu);
 
    EventFunctionWrapper *postIntEvent[CPU_MAX];
    EventFunctionWrapper *postFiqEvent[CPU_MAX];
    int pendingDelayedInterrupts;
 
  public:
    using Params = GicV2Params;
    GicV2(const Params &p);
    ~GicV2();
 
    DrainState drain() override;
    void drainResume() override;
 
    void serialize(CheckpointOut &cp) const override;
    void unserialize(CheckpointIn &cp) override;
 
  public: /* PioDevice */
    AddrRangeList getAddrRanges() const override { return addrRanges; }

    Tick read(PacketPtr pkt) override;

    Tick write(PacketPtr pkt) override;
 
  public: /* BaseGic */
    void sendInt(uint32_t number) override;
    void clearInt(uint32_t number) override;
 
    void sendPPInt(uint32_t num, uint32_t cpu) override;
    void clearPPInt(uint32_t num, uint32_t cpu) override;
 
    bool supportsVersion(GicVersion version) override;
 
  protected: 
    void copyGicState(GicV2Registers* from, GicV2Registers* to);

    Tick readDistributor(PacketPtr pkt);
    uint32_t readDistributor(ContextID ctx, Addr daddr,
                             size_t resp_sz);
    uint32_t
    readDistributor(ContextID ctx, Addr daddr) override
    {
        return readDistributor(ctx, daddr, 4);
    }

    Tick readCpu(PacketPtr pkt);
    uint32_t readCpu(ContextID ctx, Addr daddr) override;

    Tick writeDistributor(PacketPtr pkt);
    void writeDistributor(ContextID ctx, Addr daddr,
                          uint32_t data, size_t data_sz);
    void
    writeDistributor(ContextID ctx, Addr daddr, uint32_t data) override
    {
        return writeDistributor(ctx, daddr, data, 4);
    }

    Tick writeCpu(PacketPtr pkt);
    void writeCpu(ContextID ctx, Addr daddr, uint32_t data) override;
};
 
} // namespace gem5
 
#endif //__DEV_ARM_GIC_H__