Archipelago » qemu

/*

 *  MIPS emulation helpers for qemu.

 * 

 *  Copyright (c) 2004-2005 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, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

#include "exec.h"

#define MIPS_DEBUG_DISAS

#define GETPC() (__builtin_return_address(0))

/*****************************************************************************/

/* Exceptions processing helpers */

void cpu_loop_exit(void)

{

    longjmp(env->jmp_env, 1);

}

void do_raise_exception_err (uint32_t exception, int error_code)

{

#if 1

    if (logfile && exception < 0x100)

        fprintf(logfile, "%s: %d %d\n", __func__, exception, error_code);

#endif

    env->exception_index = exception;

    env->error_code = error_code;

    T0 = 0;

    cpu_loop_exit();

}

void do_raise_exception (uint32_t exception)

{

    do_raise_exception_err(exception, 0);

}

void do_restore_state (void *pc_ptr)

{

  TranslationBlock *tb;

  unsigned long pc = (unsigned long) pc_ptr;

  tb = tb_find_pc (pc);

  cpu_restore_state (tb, env, pc, NULL);

}

void do_raise_exception_direct (uint32_t exception)

{

    do_restore_state (GETPC ());

    do_raise_exception_err (exception, 0);

}

#define MEMSUFFIX _raw

#include "op_helper_mem.c"

#undef MEMSUFFIX

#if !defined(CONFIG_USER_ONLY)

#define MEMSUFFIX _user

#include "op_helper_mem.c"

#undef MEMSUFFIX

#define MEMSUFFIX _kernel

#include "op_helper_mem.c"

#undef MEMSUFFIX

#endif

/* 64 bits arithmetic for 32 bits hosts */

#if (HOST_LONG_BITS == 32)

static inline uint64_t get_HILO (void)

{

    return ((uint64_t)env->HI << 32) | (uint64_t)env->LO;

}

static inline void set_HILO (uint64_t HILO)

{

    env->LO = HILO & 0xFFFFFFFF;

    env->HI = HILO >> 32;

}

void do_mult (void)

{

    set_HILO((int64_t)(int32_t)T0 * (int64_t)(int32_t)T1);

}

void do_multu (void)

{

    set_HILO((uint64_t)T0 * (uint64_t)T1);

}

void do_madd (void)

{

    int64_t tmp;

    tmp = ((int64_t)(int32_t)T0 * (int64_t)(int32_t)T1);

    set_HILO((int64_t)get_HILO() + tmp);

}

void do_maddu (void)

{

    uint64_t tmp;

    tmp = ((uint64_t)T0 * (uint64_t)T1);

    set_HILO(get_HILO() + tmp);

}

void do_msub (void)

{

    int64_t tmp;

    tmp = ((int64_t)(int32_t)T0 * (int64_t)(int32_t)T1);

    set_HILO((int64_t)get_HILO() - tmp);

}

void do_msubu (void)

{

    uint64_t tmp;

    tmp = ((uint64_t)T0 * (uint64_t)T1);

    set_HILO(get_HILO() - tmp);

}

#endif

#if defined(CONFIG_USER_ONLY) 

void do_mfc0_random (void)

{

    cpu_abort(env, "mfc0 random\n");

}

void do_mfc0_count (void)

{

    cpu_abort(env, "mfc0 count\n");

}

void cpu_mips_store_count(CPUState *env, uint32_t value)

{

    cpu_abort(env, "mtc0 count\n");

}

void cpu_mips_store_compare(CPUState *env, uint32_t value)

{

    cpu_abort(env, "mtc0 compare\n");

}

void do_mtc0_status_debug(uint32_t old, uint32_t val)

{

    cpu_abort(env, "mtc0 status\n");

}

void do_mtc0_status_irqraise_debug(void)

{

    cpu_abort(env, "mtc0 status\n");

}

void do_tlbwi (void)

{

    cpu_abort(env, "tlbwi\n");

}

void do_tlbwr (void)

{

    cpu_abort(env, "tlbwr\n");

}

void do_tlbp (void)

{

    cpu_abort(env, "tlbp\n");

}

void do_tlbr (void)

{

    cpu_abort(env, "tlbr\n");

}

void cpu_mips_tlb_flush (CPUState *env, int flush_global)

{

    cpu_abort(env, "mips_tlb_flush\n");

}

#else

/* CP0 helpers */

void do_mfc0_random (void)

{

    T0 = cpu_mips_get_random(env);

}

void do_mfc0_count (void)

{

    T0 = cpu_mips_get_count(env);

}

void do_mtc0_status_debug(uint32_t old, uint32_t val)

{

    const uint32_t mask = 0x0000FF00;

    fprintf(logfile, "Status %08x => %08x Cause %08x (%08x %08x %08x)\n",

            old, val, env->CP0_Cause, old & mask, val & mask,

            env->CP0_Cause & mask);

}

void do_mtc0_status_irqraise_debug(void)

{

    fprintf(logfile, "Raise pending IRQs\n");

}

#ifdef MIPS_USES_FPU

#include "softfloat.h"

void fpu_handle_exception(void)

{

#ifdef CONFIG_SOFTFLOAT

    int flags = get_float_exception_flags(&env->fp_status);

    unsigned int cpuflags = 0, enable, cause = 0;

    enable = GET_FP_ENABLE(env->fcr31);

    /* determine current flags */   

    if (flags & float_flag_invalid) {

        cpuflags |= FP_INVALID;

        cause |= FP_INVALID & enable;

    }

    if (flags & float_flag_divbyzero) {

        cpuflags |= FP_DIV0;    

        cause |= FP_DIV0 & enable;

    }

    if (flags & float_flag_overflow) {

        cpuflags |= FP_OVERFLOW;    

        cause |= FP_OVERFLOW & enable;

    }

    if (flags & float_flag_underflow) {

        cpuflags |= FP_UNDERFLOW;   

        cause |= FP_UNDERFLOW & enable;

    }

    if (flags & float_flag_inexact) {

        cpuflags |= FP_INEXACT; 

        cause |= FP_INEXACT & enable;

    }

    SET_FP_FLAGS(env->fcr31, cpuflags);

    SET_FP_CAUSE(env->fcr31, cause);

#else

    SET_FP_FLAGS(env->fcr31, 0);

    SET_FP_CAUSE(env->fcr31, 0);

#endif

}

#endif /* MIPS_USES_FPU */

/* TLB management */

#if defined(MIPS_USES_R4K_TLB)

void cpu_mips_tlb_flush (CPUState *env, int flush_global)

{

    /* Flush qemu's TLB and discard all shadowed entries.  */

    tlb_flush (env, flush_global);

    env->tlb_in_use = MIPS_TLB_NB;

}

static void invalidate_tlb (int idx, int use_extra)

{

    tlb_t *tlb;

    target_ulong addr;

    uint8_t ASID;

    ASID = env->CP0_EntryHi & 0xFF;

    tlb = &env->tlb[idx];

    /* The qemu TLB is flushed then the ASID changes, so no need to

       flush these entries again.  */

    if (tlb->G == 0 && tlb->ASID != ASID) {

        return;

    }

    if (use_extra && env->tlb_in_use < MIPS_TLB_MAX) {

        /* For tlbwr, we can shadow the discarded entry into

           a new (fake) TLB entry, as long as the guest can not

           tell that it's there.  */

        env->tlb[env->tlb_in_use] = *tlb;

        env->tlb_in_use++;

        return;

    }

    if (tlb->V0) {

        tb_invalidate_page_range(tlb->PFN[0], tlb->end - tlb->VPN);

        addr = tlb->VPN;

        while (addr < tlb->end) {

            tlb_flush_page (env, addr);

            addr += TARGET_PAGE_SIZE;

        }

    }

    if (tlb->V1) {

        tb_invalidate_page_range(tlb->PFN[1], tlb->end2 - tlb->end);

        addr = tlb->end;

        while (addr < tlb->end2) {

            tlb_flush_page (env, addr);

            addr += TARGET_PAGE_SIZE;

        }

    }

}

static void mips_tlb_flush_extra (CPUState *env, int first)

{

    /* Discard entries from env->tlb[first] onwards.  */

    while (env->tlb_in_use > first) {

        invalidate_tlb(--env->tlb_in_use, 0);

    }

}

static void fill_tlb (int idx)

{

    tlb_t *tlb;

    int size;

    /* XXX: detect conflicting TLBs and raise a MCHECK exception when needed */

    tlb = &env->tlb[idx];

    tlb->VPN = env->CP0_EntryHi & 0xFFFFE000;

    tlb->ASID = env->CP0_EntryHi & 0xFF;

    size = env->CP0_PageMask >> 13;

    size = 4 * (size + 1);

    tlb->end = tlb->VPN + (1 << (8 + size));

    tlb->end2 = tlb->end + (1 << (8 + size));

    tlb->G = env->CP0_EntryLo0 & env->CP0_EntryLo1 & 1;

    tlb->V0 = (env->CP0_EntryLo0 & 2) != 0;

    tlb->D0 = (env->CP0_EntryLo0 & 4) != 0;

    tlb->C0 = (env->CP0_EntryLo0 >> 3) & 0x7;

    tlb->PFN[0] = (env->CP0_EntryLo0 >> 6) << 12;

    tlb->V1 = (env->CP0_EntryLo1 & 2) != 0;

    tlb->D1 = (env->CP0_EntryLo1 & 4) != 0;

    tlb->C1 = (env->CP0_EntryLo1 >> 3) & 0x7;

    tlb->PFN[1] = (env->CP0_EntryLo1 >> 6) << 12;

}

void do_tlbwi (void)

{

    /* Discard cached TLB entries.  We could avoid doing this if the

       tlbwi is just upgrading access permissions on the current entry;

       that might be a further win.  */

    mips_tlb_flush_extra (env, MIPS_TLB_NB);

    /* Wildly undefined effects for CP0_index containing a too high value and

       MIPS_TLB_NB not being a power of two.  But so does real silicon.  */

    invalidate_tlb(env->CP0_index & (MIPS_TLB_NB - 1), 0);

    fill_tlb(env->CP0_index & (MIPS_TLB_NB - 1));

}

void do_tlbwr (void)

{

    int r = cpu_mips_get_random(env);

    invalidate_tlb(r, 1);

    fill_tlb(r);

}

void do_tlbp (void)

{

    tlb_t *tlb;

    target_ulong tag;

    uint8_t ASID;

    int i;

    tag = env->CP0_EntryHi & 0xFFFFE000;

    ASID = env->CP0_EntryHi & 0xFF;

    for (i = 0; i < MIPS_TLB_NB; i++) {

        tlb = &env->tlb[i];

        /* Check ASID, virtual page number & size */

        if ((tlb->G == 1 || tlb->ASID == ASID) && tlb->VPN == tag) {

            /* TLB match */

            env->CP0_index = i;

            break;

        }

    }

    if (i == MIPS_TLB_NB) {

        /* No match.  Discard any shadow entries, if any of them match.  */

        for (i = MIPS_TLB_NB; i < env->tlb_in_use; i++) {

            tlb = &env->tlb[i];

            /* Check ASID, virtual page number & size */

            if ((tlb->G == 1 || tlb->ASID == ASID) && tlb->VPN == tag) {

                mips_tlb_flush_extra (env, i);

                break;

            }

        }

        env->CP0_index |= 0x80000000;

    }

}

void do_tlbr (void)

{

    tlb_t *tlb;

    uint8_t ASID;

    int size;

    ASID = env->CP0_EntryHi & 0xFF;

    tlb = &env->tlb[env->CP0_index & (MIPS_TLB_NB - 1)];

    /* If this will change the current ASID, flush qemu's TLB.  */

    if (ASID != tlb->ASID)

        cpu_mips_tlb_flush (env, 1);

    mips_tlb_flush_extra(env, MIPS_TLB_NB);

    env->CP0_EntryHi = tlb->VPN | tlb->ASID;

    size = (tlb->end - tlb->VPN) >> 12;

    env->CP0_PageMask = (size - 1) << 13;

    env->CP0_EntryLo0 = tlb->G | (tlb->V0 << 1) | (tlb->D0 << 2)

                | (tlb->C0 << 3) | (tlb->PFN[0] >> 6);

    env->CP0_EntryLo1 = tlb->G | (tlb->V1 << 1) | (tlb->D1 << 2)

                | (tlb->C1 << 3) | (tlb->PFN[1] >> 6);

}

#endif

#endif /* !CONFIG_USER_ONLY */

void op_dump_ldst (const unsigned char *func)

{

    if (loglevel)

        fprintf(logfile, "%s => %08x %08x\n", __func__, T0, T1);

}

void dump_sc (void)

{

    if (loglevel) {

        fprintf(logfile, "%s %08x at %08x (%08x)\n", __func__,

                T1, T0, env->CP0_LLAddr);

    }

}

void debug_eret (void)

{

    if (loglevel) {

        fprintf(logfile, "ERET: pc %08x EPC %08x ErrorEPC %08x (%d)\n",

                env->PC, env->CP0_EPC, env->CP0_ErrorEPC,

                env->hflags & MIPS_HFLAG_ERL ? 1 : 0);

    }

}

void do_pmon (int function)

{

    function /= 2;

    switch (function) {

    case 2: /* TODO: char inbyte(int waitflag); */

        if (env->gpr[4] == 0)

            env->gpr[2] = -1;

        /* Fall through */

    case 11: /* TODO: char inbyte (void); */

        env->gpr[2] = -1;

        break;

    case 3:

    case 12:

        printf("%c", env->gpr[4] & 0xFF);

        break;

    case 17:

        break;

    case 158:

        {

            unsigned char *fmt = (void *)env->gpr[4];

            printf("%s", fmt);

        }

        break;

    }

}

#if !defined(CONFIG_USER_ONLY) 

static void do_unaligned_access (target_ulong addr, int is_write, int is_user, void *retaddr);

#define MMUSUFFIX _mmu

#define ALIGNED_ONLY

#define SHIFT 0

#include "softmmu_template.h"

#define SHIFT 1

#include "softmmu_template.h"

#define SHIFT 2

#include "softmmu_template.h"

#define SHIFT 3

#include "softmmu_template.h"

static void do_unaligned_access (target_ulong addr, int is_write, int is_user, void *retaddr)

{

    env->CP0_BadVAddr = addr;

    do_restore_state (retaddr);

    do_raise_exception ((is_write == 1) ? EXCP_AdES : EXCP_AdEL);

}

void tlb_fill (target_ulong addr, int is_write, int is_user, void *retaddr)

{

    TranslationBlock *tb;

    CPUState *saved_env;

    unsigned long pc;

    int ret;

    /* XXX: hack to restore env in all cases, even if not called from

       generated code */

    saved_env = env;

    env = cpu_single_env;

    ret = cpu_mips_handle_mmu_fault(env, addr, is_write, is_user, 1);

    if (ret) {

        if (retaddr) {

            /* now we have a real cpu fault */

            pc = (unsigned long)retaddr;

            tb = tb_find_pc(pc);

            if (tb) {

                /* the PC is inside the translated code. It means that we have

                   a virtual CPU fault */

                cpu_restore_state(tb, env, pc, NULL);

            }

        }

        do_raise_exception_err(env->exception_index, env->error_code);

    }

    env = saved_env;

}

#endif