qemu/target-ppc/excp_helper.c

/*
 *  PowerPC exception emulation helpers for QEMU.
 *
 *  Copyright (c) 2003-2007 Jocelyn Mayer
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 */
#include "cpu.h"
#include "helper.h"

#include "helper_regs.h"

//#define DEBUG_OP
//#define DEBUG_EXCEPTIONS

#ifdef DEBUG_EXCEPTIONS
#  define LOG_EXCP(...) qemu_log(__VA_ARGS__)
#else
#  define LOG_EXCP(...) do { } while (0)
#endif

/*****************************************************************************/
/* PowerPC Hypercall emulation */

void (*cpu_ppc_hypercall)(PowerPCCPU *);

/*****************************************************************************/
/* Exception processing */
#if defined(CONFIG_USER_ONLY)
void do_interrupt(CPUPPCState *env)
{
    env->exception_index = POWERPC_EXCP_NONE;
    env->error_code = 0;
}

void ppc_hw_interrupt(CPUPPCState *env)
{
    env->exception_index = POWERPC_EXCP_NONE;
    env->error_code = 0;
}
#else /* defined(CONFIG_USER_ONLY) */
static inline void dump_syscall(CPUPPCState *env)
{
    qemu_log_mask(CPU_LOG_INT, "syscall r0=%016" PRIx64 " r3=%016" PRIx64
                  " r4=%016" PRIx64 " r5=%016" PRIx64 " r6=%016" PRIx64
                  " nip=" TARGET_FMT_lx "\n",
                  ppc_dump_gpr(env, 0), ppc_dump_gpr(env, 3),
                  ppc_dump_gpr(env, 4), ppc_dump_gpr(env, 5),
                  ppc_dump_gpr(env, 6), env->nip);
}

/* Note that this function should be greatly optimized
 * when called with a constant excp, from ppc_hw_interrupt
 */
static inline void powerpc_excp(PowerPCCPU *cpu, int excp_model, int excp)
{
    CPUPPCState *env = &cpu->env;
    target_ulong msr, new_msr, vector;
    int srr0, srr1, asrr0, asrr1;
    int lpes0, lpes1, lev;

    if (0) {
        /* XXX: find a suitable condition to enable the hypervisor mode */
        lpes0 = (env->spr[SPR_LPCR] >> 1) & 1;
        lpes1 = (env->spr[SPR_LPCR] >> 2) & 1;
    } else {
        /* Those values ensure we won't enter the hypervisor mode */
        lpes0 = 0;
        lpes1 = 1;
    }

    qemu_log_mask(CPU_LOG_INT, "Raise exception at " TARGET_FMT_lx
                  " => %08x (%02x)\n", env->nip, excp, env->error_code);

    /* new srr1 value excluding must-be-zero bits */
    if (excp_model == POWERPC_EXCP_BOOKE) {
        msr = env->msr;
    } else {
        msr = env->msr & ~0x783f0000ULL;
    }

    /* new interrupt handler msr */
    new_msr = env->msr & ((target_ulong)1 << MSR_ME);

    /* target registers */
    srr0 = SPR_SRR0;
    srr1 = SPR_SRR1;
    asrr0 = -1;
    asrr1 = -1;

    switch (excp) {
    case POWERPC_EXCP_NONE:
        /* Should never happen */
        return;
    case POWERPC_EXCP_CRITICAL:    /* Critical input                         */
        switch (excp_model) {
        case POWERPC_EXCP_40x:
            srr0 = SPR_40x_SRR2;
            srr1 = SPR_40x_SRR3;
            break;
        case POWERPC_EXCP_BOOKE:
            srr0 = SPR_BOOKE_CSRR0;
            srr1 = SPR_BOOKE_CSRR1;
            break;
        case POWERPC_EXCP_G2:
            break;
        default:
            goto excp_invalid;
        }
        goto store_next;
    case POWERPC_EXCP_MCHECK:    /* Machine check exception                  */
        if (msr_me == 0) {
            /* Machine check exception is not enabled.
             * Enter checkstop state.
             */
            if (qemu_log_enabled()) {
                qemu_log("Machine check while not allowed. "
                        "Entering checkstop state\n");
            } else {
                fprintf(stderr, "Machine check while not allowed. "
                        "Entering checkstop state\n");
            }
            env->halted = 1;
            env->interrupt_request |= CPU_INTERRUPT_EXITTB;
        }
        if (0) {
            /* XXX: find a suitable condition to enable the hypervisor mode */
            new_msr |= (target_ulong)MSR_HVB;
        }

        /* machine check exceptions don't have ME set */
        new_msr &= ~((target_ulong)1 << MSR_ME);

        /* XXX: should also have something loaded in DAR / DSISR */
        switch (excp_model) {
        case POWERPC_EXCP_40x:
            srr0 = SPR_40x_SRR2;
            srr1 = SPR_40x_SRR3;
            break;
        case POWERPC_EXCP_BOOKE:
            /* FIXME: choose one or the other based on CPU type */
            srr0 = SPR_BOOKE_MCSRR0;
            srr1 = SPR_BOOKE_MCSRR1;
            asrr0 = SPR_BOOKE_CSRR0;
            asrr1 = SPR_BOOKE_CSRR1;
            break;
        default:
            break;
        }
        goto store_next;
    case POWERPC_EXCP_DSI:       /* Data storage exception                   */
        LOG_EXCP("DSI exception: DSISR=" TARGET_FMT_lx" DAR=" TARGET_FMT_lx
                 "\n", env->spr[SPR_DSISR], env->spr[SPR_DAR]);
        if (lpes1 == 0) {
            new_msr |= (target_ulong)MSR_HVB;
        }
        goto store_next;
    case POWERPC_EXCP_ISI:       /* Instruction storage exception            */
        LOG_EXCP("ISI exception: msr=" TARGET_FMT_lx ", nip=" TARGET_FMT_lx
                 "\n", msr, env->nip);
        if (lpes1 == 0) {
            new_msr |= (target_ulong)MSR_HVB;
        }
        msr |= env->error_code;
        goto store_next;
    case POWERPC_EXCP_EXTERNAL:  /* External input                           */
        if (lpes0 == 1) {
            new_msr |= (target_ulong)MSR_HVB;
        }
        if (env->mpic_proxy) {
            /* IACK the IRQ on delivery */
            env->spr[SPR_BOOKE_EPR] = ldl_phys(env->mpic_iack);
        }
        goto store_next;
    case POWERPC_EXCP_ALIGN:     /* Alignment exception                      */
        if (lpes1 == 0) {
            new_msr |= (target_ulong)MSR_HVB;
        }
        /* XXX: this is false */
        /* Get rS/rD and rA from faulting opcode */
        env->spr[SPR_DSISR] |= (cpu_ldl_code(env, (env->nip - 4))
                                & 0x03FF0000) >> 16;
        goto store_current;
    case POWERPC_EXCP_PROGRAM:   /* Program exception                        */
        switch (env->error_code & ~0xF) {
        case POWERPC_EXCP_FP:
            if ((msr_fe0 == 0 && msr_fe1 == 0) || msr_fp == 0) {
                LOG_EXCP("Ignore floating point exception\n");
                env->exception_index = POWERPC_EXCP_NONE;
                env->error_code = 0;
                return;
            }
            if (lpes1 == 0) {
                new_msr |= (target_ulong)MSR_HVB;
            }
            msr |= 0x00100000;
            if (msr_fe0 == msr_fe1) {
                goto store_next;
            }
            msr |= 0x00010000;
            break;
        case POWERPC_EXCP_INVAL:
            LOG_EXCP("Invalid instruction at " TARGET_FMT_lx "\n", env->nip);
            if (lpes1 == 0) {
                new_msr |= (target_ulong)MSR_HVB;
            }
            msr |= 0x00080000;
            env->spr[SPR_BOOKE_ESR] = ESR_PIL;
            break;
        case POWERPC_EXCP_PRIV:
            if (lpes1 == 0) {
                new_msr |= (target_ulong)MSR_HVB;
            }
            msr |= 0x00040000;
            env->spr[SPR_BOOKE_ESR] = ESR_PPR;
            break;
        case POWERPC_EXCP_TRAP:
            if (lpes1 == 0) {
                new_msr |= (target_ulong)MSR_HVB;
            }
            msr |= 0x00020000;
            env->spr[SPR_BOOKE_ESR] = ESR_PTR;
            break;
        default:
            /* Should never occur */
            cpu_abort(env, "Invalid program exception %d. Aborting\n",
                      env->error_code);
            break;
        }
        goto store_current;
    case POWERPC_EXCP_FPU:       /* Floating-point unavailable exception     */
        if (lpes1 == 0) {
            new_msr |= (target_ulong)MSR_HVB;
        }
        goto store_current;
    case POWERPC_EXCP_SYSCALL:   /* System call exception                    */
        dump_syscall(env);
        lev = env->error_code;
        if ((lev == 1) && cpu_ppc_hypercall) {
            cpu_ppc_hypercall(cpu);
            return;
        }
        if (lev == 1 || (lpes0 == 0 && lpes1 == 0)) {
            new_msr |= (target_ulong)MSR_HVB;
        }
        goto store_next;
    case POWERPC_EXCP_APU:       /* Auxiliary processor unavailable          */
        goto store_current;
    case POWERPC_EXCP_DECR:      /* Decrementer exception                    */
        if (lpes1 == 0) {
            new_msr |= (target_ulong)MSR_HVB;
        }
        goto store_next;
    case POWERPC_EXCP_FIT:       /* Fixed-interval timer interrupt           */
        /* FIT on 4xx */
        LOG_EXCP("FIT exception\n");
        goto store_next;
    case POWERPC_EXCP_WDT:       /* Watchdog timer interrupt                 */
        LOG_EXCP("WDT exception\n");
        switch (excp_model) {
        case POWERPC_EXCP_BOOKE:
            srr0 = SPR_BOOKE_CSRR0;
            srr1 = SPR_BOOKE_CSRR1;
            break;
        default:
            break;
        }
        goto store_next;
    case POWERPC_EXCP_DTLB:      /* Data TLB error                           */
        goto store_next;
    case POWERPC_EXCP_ITLB:      /* Instruction TLB error                    */
        goto store_next;
    case POWERPC_EXCP_DEBUG:     /* Debug interrupt                          */
        switch (excp_model) {
        case POWERPC_EXCP_BOOKE:
            /* FIXME: choose one or the other based on CPU type */
            srr0 = SPR_BOOKE_DSRR0;
            srr1 = SPR_BOOKE_DSRR1;
            asrr0 = SPR_BOOKE_CSRR0;
            asrr1 = SPR_BOOKE_CSRR1;
            break;
        default:
            break;
        }
        /* XXX: TODO */
        cpu_abort(env, "Debug exception is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_SPEU:      /* SPE/embedded floating-point unavailable  */
        env->spr[SPR_BOOKE_ESR] = ESR_SPV;
        goto store_current;
    case POWERPC_EXCP_EFPDI:     /* Embedded floating-point data interrupt   */
        /* XXX: TODO */
        cpu_abort(env, "Embedded floating point data exception "
                  "is not implemented yet !\n");
        env->spr[SPR_BOOKE_ESR] = ESR_SPV;
        goto store_next;
    case POWERPC_EXCP_EFPRI:     /* Embedded floating-point round interrupt  */
        /* XXX: TODO */
        cpu_abort(env, "Embedded floating point round exception "
                  "is not implemented yet !\n");
        env->spr[SPR_BOOKE_ESR] = ESR_SPV;
        goto store_next;
    case POWERPC_EXCP_EPERFM:    /* Embedded performance monitor interrupt   */
        /* XXX: TODO */
        cpu_abort(env,
                  "Performance counter exception is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_DOORI:     /* Embedded doorbell interrupt              */
        goto store_next;
    case POWERPC_EXCP_DOORCI:    /* Embedded doorbell critical interrupt     */
        srr0 = SPR_BOOKE_CSRR0;
        srr1 = SPR_BOOKE_CSRR1;
        goto store_next;
    case POWERPC_EXCP_RESET:     /* System reset exception                   */
        if (msr_pow) {
            /* indicate that we resumed from power save mode */
            msr |= 0x10000;
        } else {
            new_msr &= ~((target_ulong)1 << MSR_ME);
        }

        if (0) {
            /* XXX: find a suitable condition to enable the hypervisor mode */
            new_msr |= (target_ulong)MSR_HVB;
        }
        goto store_next;
    case POWERPC_EXCP_DSEG:      /* Data segment exception                   */
        if (lpes1 == 0) {
            new_msr |= (target_ulong)MSR_HVB;
        }
        goto store_next;
    case POWERPC_EXCP_ISEG:      /* Instruction segment exception            */
        if (lpes1 == 0) {
            new_msr |= (target_ulong)MSR_HVB;
        }
        goto store_next;
    case POWERPC_EXCP_HDECR:     /* Hypervisor decrementer exception         */
        srr0 = SPR_HSRR0;
        srr1 = SPR_HSRR1;
        new_msr |= (target_ulong)MSR_HVB;
        new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
        goto store_next;
    case POWERPC_EXCP_TRACE:     /* Trace exception                          */
        if (lpes1 == 0) {
            new_msr |= (target_ulong)MSR_HVB;
        }
        goto store_next;
    case POWERPC_EXCP_HDSI:      /* Hypervisor data storage exception        */
        srr0 = SPR_HSRR0;
        srr1 = SPR_HSRR1;
        new_msr |= (target_ulong)MSR_HVB;
        new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
        goto store_next;
    case POWERPC_EXCP_HISI:      /* Hypervisor instruction storage exception */
        srr0 = SPR_HSRR0;
        srr1 = SPR_HSRR1;
        new_msr |= (target_ulong)MSR_HVB;
        new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
        goto store_next;
    case POWERPC_EXCP_HDSEG:     /* Hypervisor data segment exception        */
        srr0 = SPR_HSRR0;
        srr1 = SPR_HSRR1;
        new_msr |= (target_ulong)MSR_HVB;
        new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
        goto store_next;
    case POWERPC_EXCP_HISEG:     /* Hypervisor instruction segment exception */
        srr0 = SPR_HSRR0;
        srr1 = SPR_HSRR1;
        new_msr |= (target_ulong)MSR_HVB;
        new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
        goto store_next;
    case POWERPC_EXCP_VPU:       /* Vector unavailable exception             */
        if (lpes1 == 0) {
            new_msr |= (target_ulong)MSR_HVB;
        }
        goto store_current;
    case POWERPC_EXCP_PIT:       /* Programmable interval timer interrupt    */
        LOG_EXCP("PIT exception\n");
        goto store_next;
    case POWERPC_EXCP_IO:        /* IO error exception                       */
        /* XXX: TODO */
        cpu_abort(env, "601 IO error exception is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_RUNM:      /* Run mode exception                       */
        /* XXX: TODO */
        cpu_abort(env, "601 run mode exception is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_EMUL:      /* Emulation trap exception                 */
        /* XXX: TODO */
        cpu_abort(env, "602 emulation trap exception "
                  "is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_IFTLB:     /* Instruction fetch TLB error              */
        if (lpes1 == 0) { /* XXX: check this */
            new_msr |= (target_ulong)MSR_HVB;
        }
        switch (excp_model) {
        case POWERPC_EXCP_602:
        case POWERPC_EXCP_603:
        case POWERPC_EXCP_603E:
        case POWERPC_EXCP_G2:
            goto tlb_miss_tgpr;
        case POWERPC_EXCP_7x5:
            goto tlb_miss;
        case POWERPC_EXCP_74xx:
            goto tlb_miss_74xx;
        default:
            cpu_abort(env, "Invalid instruction TLB miss exception\n");
            break;
        }
        break;
    case POWERPC_EXCP_DLTLB:     /* Data load TLB miss                       */
        if (lpes1 == 0) { /* XXX: check this */
            new_msr |= (target_ulong)MSR_HVB;
        }
        switch (excp_model) {
        case POWERPC_EXCP_602:
        case POWERPC_EXCP_603:
        case POWERPC_EXCP_603E:
        case POWERPC_EXCP_G2:
            goto tlb_miss_tgpr;
        case POWERPC_EXCP_7x5:
            goto tlb_miss;
        case POWERPC_EXCP_74xx:
            goto tlb_miss_74xx;
        default:
            cpu_abort(env, "Invalid data load TLB miss exception\n");
            break;
        }
        break;
    case POWERPC_EXCP_DSTLB:     /* Data store TLB miss                      */
        if (lpes1 == 0) { /* XXX: check this */
            new_msr |= (target_ulong)MSR_HVB;
        }
        switch (excp_model) {
        case POWERPC_EXCP_602:
        case POWERPC_EXCP_603:
        case POWERPC_EXCP_603E:
        case POWERPC_EXCP_G2:
        tlb_miss_tgpr:
            /* Swap temporary saved registers with GPRs */
            if (!(new_msr & ((target_ulong)1 << MSR_TGPR))) {
                new_msr |= (target_ulong)1 << MSR_TGPR;
                hreg_swap_gpr_tgpr(env);
            }
            goto tlb_miss;
        case POWERPC_EXCP_7x5:
        tlb_miss:
#if defined(DEBUG_SOFTWARE_TLB)
            if (qemu_log_enabled()) {
                const char *es;
                target_ulong *miss, *cmp;
                int en;

                if (excp == POWERPC_EXCP_IFTLB) {
                    es = "I";
                    en = 'I';
                    miss = &env->spr[SPR_IMISS];
                    cmp = &env->spr[SPR_ICMP];
                } else {
                    if (excp == POWERPC_EXCP_DLTLB) {
                        es = "DL";
                    } else {
                        es = "DS";
                    }
                    en = 'D';
                    miss = &env->spr[SPR_DMISS];
                    cmp = &env->spr[SPR_DCMP];
                }
                qemu_log("6xx %sTLB miss: %cM " TARGET_FMT_lx " %cC "
                         TARGET_FMT_lx " H1 " TARGET_FMT_lx " H2 "
                         TARGET_FMT_lx " %08x\n", es, en, *miss, en, *cmp,
                         env->spr[SPR_HASH1], env->spr[SPR_HASH2],
                         env->error_code);
            }
#endif
            msr |= env->crf[0] << 28;
            msr |= env->error_code; /* key, D/I, S/L bits */
            /* Set way using a LRU mechanism */
            msr |= ((env->last_way + 1) & (env->nb_ways - 1)) << 17;
            break;
        case POWERPC_EXCP_74xx:
        tlb_miss_74xx:
#if defined(DEBUG_SOFTWARE_TLB)
            if (qemu_log_enabled()) {
                const char *es;
                target_ulong *miss, *cmp;
                int en;

                if (excp == POWERPC_EXCP_IFTLB) {
                    es = "I";
                    en = 'I';
                    miss = &env->spr[SPR_TLBMISS];
                    cmp = &env->spr[SPR_PTEHI];
                } else {
                    if (excp == POWERPC_EXCP_DLTLB) {
                        es = "DL";
                    } else {
                        es = "DS";
                    }
                    en = 'D';
                    miss = &env->spr[SPR_TLBMISS];
                    cmp = &env->spr[SPR_PTEHI];
                }
                qemu_log("74xx %sTLB miss: %cM " TARGET_FMT_lx " %cC "
                         TARGET_FMT_lx " %08x\n", es, en, *miss, en, *cmp,
                         env->error_code);
            }
#endif
            msr |= env->error_code; /* key bit */
            break;
        default:
            cpu_abort(env, "Invalid data store TLB miss exception\n");
            break;
        }
        goto store_next;
    case POWERPC_EXCP_FPA:       /* Floating-point assist exception          */
        /* XXX: TODO */
        cpu_abort(env, "Floating point assist exception "
                  "is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_DABR:      /* Data address breakpoint                  */
        /* XXX: TODO */
        cpu_abort(env, "DABR exception is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_IABR:      /* Instruction address breakpoint           */
        /* XXX: TODO */
        cpu_abort(env, "IABR exception is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_SMI:       /* System management interrupt              */
        /* XXX: TODO */
        cpu_abort(env, "SMI exception is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_THERM:     /* Thermal interrupt                        */
        /* XXX: TODO */
        cpu_abort(env, "Thermal management exception "
                  "is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_PERFM:     /* Embedded performance monitor interrupt   */
        if (lpes1 == 0) {
            new_msr |= (target_ulong)MSR_HVB;
        }
        /* XXX: TODO */
        cpu_abort(env,
                  "Performance counter exception is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_VPUA:      /* Vector assist exception                  */
        /* XXX: TODO */
        cpu_abort(env, "VPU assist exception is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_SOFTP:     /* Soft patch exception                     */
        /* XXX: TODO */
        cpu_abort(env,
                  "970 soft-patch exception is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_MAINT:     /* Maintenance exception                    */
        /* XXX: TODO */
        cpu_abort(env,
                  "970 maintenance exception is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_MEXTBR:    /* Maskable external breakpoint             */
        /* XXX: TODO */
        cpu_abort(env, "Maskable external exception "
                  "is not implemented yet !\n");
        goto store_next;
    case POWERPC_EXCP_NMEXTBR:   /* Non maskable external breakpoint         */
        /* XXX: TODO */
        cpu_abort(env, "Non maskable external exception "
                  "is not implemented yet !\n");
        goto store_next;
    default:
    excp_invalid:
        cpu_abort(env, "Invalid PowerPC exception %d. Aborting\n", excp);
        break;
    store_current:
        /* save current instruction location */
        env->spr[srr0] = env->nip - 4;
        break;
    store_next:
        /* save next instruction location */
        env->spr[srr0] = env->nip;
        break;
    }
    /* Save MSR */
    env->spr[srr1] = msr;
    /* If any alternate SRR register are defined, duplicate saved values */
    if (asrr0 != -1) {
        env->spr[asrr0] = env->spr[srr0];
    }
    if (asrr1 != -1) {
        env->spr[asrr1] = env->spr[srr1];
    }
    /* If we disactivated any translation, flush TLBs */
    if (msr & ((1 << MSR_IR) | (1 << MSR_DR))) {
        tlb_flush(env, 1);
    }

    if (msr_ile) {
        new_msr |= (target_ulong)1 << MSR_LE;
    }

    /* Jump to handler */
    vector = env->excp_vectors[excp];
    if (vector == (target_ulong)-1ULL) {
        cpu_abort(env, "Raised an exception without defined vector %d\n",
                  excp);
    }
    vector |= env->excp_prefix;
#if defined(TARGET_PPC64)
    if (excp_model == POWERPC_EXCP_BOOKE) {
        if (env->spr[SPR_BOOKE_EPCR] & EPCR_ICM) {
            /* Cat.64-bit: EPCR.ICM is copied to MSR.CM */
            new_msr |= (target_ulong)1 << MSR_CM;
        } else {
            vector = (uint32_t)vector;
        }
    } else {
        if (!msr_isf && !(env->mmu_model & POWERPC_MMU_64)) {
            vector = (uint32_t)vector;
        } else {
            new_msr |= (target_ulong)1 << MSR_SF;
        }
    }
#endif
    /* XXX: we don't use hreg_store_msr here as already have treated
     *      any special case that could occur. Just store MSR and update hflags
     */
    env->msr = new_msr & env->msr_mask;
    hreg_compute_hflags(env);
    env->nip = vector;
    /* Reset exception state */
    env->exception_index = POWERPC_EXCP_NONE;
    env->error_code = 0;

    if ((env->mmu_model == POWERPC_MMU_BOOKE) ||
        (env->mmu_model == POWERPC_MMU_BOOKE206)) {
        /* XXX: The BookE changes address space when switching modes,
                we should probably implement that as different MMU indexes,
                but for the moment we do it the slow way and flush all.  */
        tlb_flush(env, 1);
    }
}

void do_interrupt(CPUPPCState *env)
{
    PowerPCCPU *cpu = ppc_env_get_cpu(env);

    powerpc_excp(cpu, env->excp_model, env->exception_index);
}

void ppc_hw_interrupt(CPUPPCState *env)
{
    PowerPCCPU *cpu = ppc_env_get_cpu(env);
    int hdice;

#if 0
    qemu_log_mask(CPU_LOG_INT, "%s: %p pending %08x req %08x me %d ee %d\n",
                __func__, env, env->pending_interrupts,
                env->interrupt_request, (int)msr_me, (int)msr_ee);
#endif
    /* External reset */
    if (env->pending_interrupts & (1 << PPC_INTERRUPT_RESET)) {
        env->pending_interrupts &= ~(1 << PPC_INTERRUPT_RESET);
        powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_RESET);
        return;
    }
    /* Machine check exception */
    if (env->pending_interrupts & (1 << PPC_INTERRUPT_MCK)) {
        env->pending_interrupts &= ~(1 << PPC_INTERRUPT_MCK);
        powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_MCHECK);
        return;
    }
#if 0 /* TODO */
    /* External debug exception */
    if (env->pending_interrupts & (1 << PPC_INTERRUPT_DEBUG)) {
        env->pending_interrupts &= ~(1 << PPC_INTERRUPT_DEBUG);
        powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_DEBUG);
        return;
    }
#endif
    if (0) {
        /* XXX: find a suitable condition to enable the hypervisor mode */
        hdice = env->spr[SPR_LPCR] & 1;
    } else {
        hdice = 0;
    }
    if ((msr_ee != 0 || msr_hv == 0 || msr_pr != 0) && hdice != 0) {
        /* Hypervisor decrementer exception */
        if (env->pending_interrupts & (1 << PPC_INTERRUPT_HDECR)) {
            env->pending_interrupts &= ~(1 << PPC_INTERRUPT_HDECR);
            powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_HDECR);
            return;
        }
    }
    if (msr_ce != 0) {
        /* External critical interrupt */
        if (env->pending_interrupts & (1 << PPC_INTERRUPT_CEXT)) {
            /* Taking a critical external interrupt does not clear the external
             * critical interrupt status
             */
#if 0
            env->pending_interrupts &= ~(1 << PPC_INTERRUPT_CEXT);
#endif
            powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_CRITICAL);
            return;
        }
    }
    if (msr_ee != 0) {
        /* Watchdog timer on embedded PowerPC */
        if (env->pending_interrupts & (1 << PPC_INTERRUPT_WDT)) {
            env->pending_interrupts &= ~(1 << PPC_INTERRUPT_WDT);
            powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_WDT);
            return;
        }
        if (env->pending_interrupts & (1 << PPC_INTERRUPT_CDOORBELL)) {
            env->pending_interrupts &= ~(1 << PPC_INTERRUPT_CDOORBELL);
            powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_DOORCI);
            return;
        }
        /* Fixed interval timer on embedded PowerPC */
        if (env->pending_interrupts & (1 << PPC_INTERRUPT_FIT)) {
            env->pending_interrupts &= ~(1 << PPC_INTERRUPT_FIT);
            powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_FIT);
            return;
        }
        /* Programmable interval timer on embedded PowerPC */
        if (env->pending_interrupts & (1 << PPC_INTERRUPT_PIT)) {
            env->pending_interrupts &= ~(1 << PPC_INTERRUPT_PIT);
            powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_PIT);
            return;
        }
        /* Decrementer exception */
        if (env->pending_interrupts & (1 << PPC_INTERRUPT_DECR)) {
            env->pending_interrupts &= ~(1 << PPC_INTERRUPT_DECR);
            powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_DECR);
            return;
        }
        /* External interrupt */
        if (env->pending_interrupts & (1 << PPC_INTERRUPT_EXT)) {
            /* Taking an external interrupt does not clear the external
             * interrupt status
             */
#if 0
            env->pending_interrupts &= ~(1 << PPC_INTERRUPT_EXT);
#endif
            powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_EXTERNAL);
            return;
        }
        if (env->pending_interrupts & (1 << PPC_INTERRUPT_DOORBELL)) {
            env->pending_interrupts &= ~(1 << PPC_INTERRUPT_DOORBELL);
            powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_DOORI);
            return;
        }
        if (env->pending_interrupts & (1 << PPC_INTERRUPT_PERFM)) {
            env->pending_interrupts &= ~(1 << PPC_INTERRUPT_PERFM);
            powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_PERFM);
            return;
        }
        /* Thermal interrupt */
        if (env->pending_interrupts & (1 << PPC_INTERRUPT_THERM)) {
            env->pending_interrupts &= ~(1 << PPC_INTERRUPT_THERM);
            powerpc_excp(cpu, env->excp_model, POWERPC_EXCP_THERM);
            return;
        }
    }
}
#endif /* !CONFIG_USER_ONLY */

#if defined(DEBUG_OP)
static void cpu_dump_rfi(target_ulong RA, target_ulong msr)
{
    qemu_log("Return from exception at " TARGET_FMT_lx " with flags "
             TARGET_FMT_lx "\n", RA, msr);
}
#endif

/*****************************************************************************/
/* Exceptions processing helpers */

void helper_raise_exception_err(CPUPPCState *env, uint32_t exception,
                                uint32_t error_code)
{
#if 0
    printf("Raise exception %3x code : %d\n", exception, error_code);
#endif
    env->exception_index = exception;
    env->error_code = error_code;
    cpu_loop_exit(env);
}

void helper_raise_exception(CPUPPCState *env, uint32_t exception)
{
    helper_raise_exception_err(env, exception, 0);
}

#if !defined(CONFIG_USER_ONLY)
void helper_store_msr(CPUPPCState *env, target_ulong val)
{
    val = hreg_store_msr(env, val, 0);
    if (val != 0) {
        env->interrupt_request |= CPU_INTERRUPT_EXITTB;
        helper_raise_exception(env, val);
    }
}

static inline void do_rfi(CPUPPCState *env, target_ulong nip, target_ulong msr,
                          target_ulong msrm, int keep_msrh)
{
#if defined(TARGET_PPC64)
    if (msr_is_64bit(env, msr)) {
        nip = (uint64_t)nip;
        msr &= (uint64_t)msrm;
    } else {
        nip = (uint32_t)nip;
        msr = (uint32_t)(msr & msrm);
        if (keep_msrh) {
            msr |= env->msr & ~((uint64_t)0xFFFFFFFF);
        }
    }
#else
    nip = (uint32_t)nip;
    msr &= (uint32_t)msrm;
#endif
    /* XXX: beware: this is false if VLE is supported */
    env->nip = nip & ~((target_ulong)0x00000003);
    hreg_store_msr(env, msr, 1);
#if defined(DEBUG_OP)
    cpu_dump_rfi(env->nip, env->msr);
#endif
    /* No need to raise an exception here,
     * as rfi is always the last insn of a TB
     */
    env->interrupt_request |= CPU_INTERRUPT_EXITTB;
}

void helper_rfi(CPUPPCState *env)
{
    if (env->excp_model == POWERPC_EXCP_BOOKE) {
        do_rfi(env, env->spr[SPR_SRR0], env->spr[SPR_SRR1],
               ~((target_ulong)0), 0);
    } else {
        do_rfi(env, env->spr[SPR_SRR0], env->spr[SPR_SRR1],
               ~((target_ulong)0x783F0000), 1);
    }
}

#if defined(TARGET_PPC64)
void helper_rfid(CPUPPCState *env)
{
    do_rfi(env, env->spr[SPR_SRR0], env->spr[SPR_SRR1],
           ~((target_ulong)0x783F0000), 0);
}

void helper_hrfid(CPUPPCState *env)
{
    do_rfi(env, env->spr[SPR_HSRR0], env->spr[SPR_HSRR1],
           ~((target_ulong)0x783F0000), 0);
}
#endif

/*****************************************************************************/
/* Embedded PowerPC specific helpers */
void helper_40x_rfci(CPUPPCState *env)
{
    do_rfi(env, env->spr[SPR_40x_SRR2], env->spr[SPR_40x_SRR3],
           ~((target_ulong)0xFFFF0000), 0);
}

void helper_rfci(CPUPPCState *env)
{
    do_rfi(env, env->spr[SPR_BOOKE_CSRR0], env->spr[SPR_BOOKE_CSRR1],
           ~((target_ulong)0), 0);
}

void helper_rfdi(CPUPPCState *env)
{
    /* FIXME: choose CSRR1 or DSRR1 based on cpu type */
    do_rfi(env, env->spr[SPR_BOOKE_DSRR0], env->spr[SPR_BOOKE_DSRR1],
           ~((target_ulong)0), 0);
}

void helper_rfmci(CPUPPCState *env)
{
    /* FIXME: choose CSRR1 or MCSRR1 based on cpu type */
    do_rfi(env, env->spr[SPR_BOOKE_MCSRR0], env->spr[SPR_BOOKE_MCSRR1],
           ~((target_ulong)0), 0);
}
#endif

void helper_tw(CPUPPCState *env, target_ulong arg1, target_ulong arg2,
               uint32_t flags)
{
    if (!likely(!(((int32_t)arg1 < (int32_t)arg2 && (flags & 0x10)) ||
                  ((int32_t)arg1 > (int32_t)arg2 && (flags & 0x08)) ||
                  ((int32_t)arg1 == (int32_t)arg2 && (flags & 0x04)) ||
                  ((uint32_t)arg1 < (uint32_t)arg2 && (flags & 0x02)) ||
                  ((uint32_t)arg1 > (uint32_t)arg2 && (flags & 0x01))))) {
        helper_raise_exception_err(env, POWERPC_EXCP_PROGRAM,
                                   POWERPC_EXCP_TRAP);
    }
}

#if defined(TARGET_PPC64)
void helper_td(CPUPPCState *env, target_ulong arg1, target_ulong arg2,
               uint32_t flags)
{
    if (!likely(!(((int64_t)arg1 < (int64_t)arg2 && (flags & 0x10)) ||
                  ((int64_t)arg1 > (int64_t)arg2 && (flags & 0x08)) ||
                  ((int64_t)arg1 == (int64_t)arg2 && (flags & 0x04)) ||
                  ((uint64_t)arg1 < (uint64_t)arg2 && (flags & 0x02)) ||
                  ((uint64_t)arg1 > (uint64_t)arg2 && (flags & 0x01))))) {
        helper_raise_exception_err(env, POWERPC_EXCP_PROGRAM,
                                   POWERPC_EXCP_TRAP);
    }
}
#endif

#if !defined(CONFIG_USER_ONLY)
/*****************************************************************************/
/* PowerPC 601 specific instructions (POWER bridge) */

void helper_rfsvc(CPUPPCState *env)
{
    do_rfi(env, env->lr, env->ctr, 0x0000FFFF, 0);
}

/* Embedded.Processor Control */
static int dbell2irq(target_ulong rb)
{
    int msg = rb & DBELL_TYPE_MASK;
    int irq = -1;

    switch (msg) {
    case DBELL_TYPE_DBELL:
        irq = PPC_INTERRUPT_DOORBELL;
        break;
    case DBELL_TYPE_DBELL_CRIT:
        irq = PPC_INTERRUPT_CDOORBELL;
        break;
    case DBELL_TYPE_G_DBELL:
    case DBELL_TYPE_G_DBELL_CRIT:
    case DBELL_TYPE_G_DBELL_MC:
        /* XXX implement */
    default:
        break;
    }

    return irq;
}

void helper_msgclr(CPUPPCState *env, target_ulong rb)
{
    int irq = dbell2irq(rb);

    if (irq < 0) {
        return;
    }

    env->pending_interrupts &= ~(1 << irq);
}

void helper_msgsnd(target_ulong rb)
{
    int irq = dbell2irq(rb);
    int pir = rb & DBELL_PIRTAG_MASK;
    CPUPPCState *cenv;

    if (irq < 0) {
        return;
    }

    for (cenv = first_cpu; cenv != NULL; cenv = cenv->next_cpu) {
        if ((rb & DBELL_BRDCAST) || (cenv->spr[SPR_BOOKE_PIR] == pir)) {
            cenv->pending_interrupts |= 1 << irq;
            cpu_interrupt(cenv, CPU_INTERRUPT_HARD);
        }
    }
}
#endif