LXR qemu/linux-user/alpha/cpu

   1/*
   2 *  qemu user cpu loop
   3 *
   4 *  Copyright (c) 2003-2008 Fabrice Bellard
   5 *
   6 *  This program is free software; you can redistribute it and/or modify
   7 *  it under the terms of the GNU General Public License as published by
   8 *  the Free Software Foundation; either version 2 of the License, or
   9 *  (at your option) any later version.
  10 *
  11 *  This program is distributed in the hope that it will be useful,
  12 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 *  GNU General Public License for more details.
  15 *
  16 *  You should have received a copy of the GNU General Public License
  17 *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20#include "qemu/osdep.h"
  21#include "qemu-common.h"
  22#include "qemu.h"
  23#include "cpu_loop-common.h"
  24
  25void cpu_loop(CPUAlphaState *env)
  26{
  27    CPUState *cs = env_cpu(env);
  28    int trapnr;
  29    target_siginfo_t info;
  30    abi_long sysret;
  31
  32    while (1) {
  33        bool arch_interrupt = true;
  34
  35        cpu_exec_start(cs);
  36        trapnr = cpu_exec(cs);
  37        cpu_exec_end(cs);
  38        process_queued_cpu_work(cs);
  39
  40        switch (trapnr) {
  41        case EXCP_RESET:
  42            fprintf(stderr, "Reset requested. Exit\n");
  43            exit(EXIT_FAILURE);
  44            break;
  45        case EXCP_MCHK:
  46            fprintf(stderr, "Machine check exception. Exit\n");
  47            exit(EXIT_FAILURE);
  48            break;
  49        case EXCP_SMP_INTERRUPT:
  50        case EXCP_CLK_INTERRUPT:
  51        case EXCP_DEV_INTERRUPT:
  52            fprintf(stderr, "External interrupt. Exit\n");
  53            exit(EXIT_FAILURE);
  54            break;
  55        case EXCP_MMFAULT:
  56            info.si_signo = TARGET_SIGSEGV;
  57            info.si_errno = 0;
  58            info.si_code = (page_get_flags(env->trap_arg0) & PAGE_VALID
  59                            ? TARGET_SEGV_ACCERR : TARGET_SEGV_MAPERR);
  60            info._sifields._sigfault._addr = env->trap_arg0;
  61            queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
  62            break;
  63        case EXCP_UNALIGN:
  64            info.si_signo = TARGET_SIGBUS;
  65            info.si_errno = 0;
  66            info.si_code = TARGET_BUS_ADRALN;
  67            info._sifields._sigfault._addr = env->trap_arg0;
  68            queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
  69            break;
  70        case EXCP_OPCDEC:
  71        do_sigill:
  72            info.si_signo = TARGET_SIGILL;
  73            info.si_errno = 0;
  74            info.si_code = TARGET_ILL_ILLOPC;
  75            info._sifields._sigfault._addr = env->pc;
  76            queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
  77            break;
  78        case EXCP_ARITH:
  79            info.si_signo = TARGET_SIGFPE;
  80            info.si_errno = 0;
  81            info.si_code = TARGET_FPE_FLTINV;
  82            info._sifields._sigfault._addr = env->pc;
  83            queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
  84            break;
  85        case EXCP_FEN:
  86            /* No-op.  Linux simply re-enables the FPU.  */
  87            break;
  88        case EXCP_CALL_PAL:
  89            switch (env->error_code) {
  90            case 0x80:
  91                /* BPT */
  92                info.si_signo = TARGET_SIGTRAP;
  93                info.si_errno = 0;
  94                info.si_code = TARGET_TRAP_BRKPT;
  95                info._sifields._sigfault._addr = env->pc;
  96                queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
  97                break;
  98            case 0x81:
  99                /* BUGCHK */
 100                info.si_signo = TARGET_SIGTRAP;
 101                info.si_errno = 0;
 102                info.si_code = 0;
 103                info._sifields._sigfault._addr = env->pc;
 104                queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
 105                break;
 106            case 0x83:
 107                /* CALLSYS */
 108                trapnr = env->ir[IR_V0];
 109                sysret = do_syscall(env, trapnr,
 110                                    env->ir[IR_A0], env->ir[IR_A1],
 111                                    env->ir[IR_A2], env->ir[IR_A3],
 112                                    env->ir[IR_A4], env->ir[IR_A5],
 113                                    0, 0);
 114                if (sysret == -TARGET_ERESTARTSYS) {
 115                    env->pc -= 4;
 116                    break;
 117                }
 118                if (sysret == -TARGET_QEMU_ESIGRETURN) {
 119                    break;
 120                }
 121                /* Syscall writes 0 to V0 to bypass error check, similar
 122                   to how this is handled internal to Linux kernel.
 123                   (Ab)use trapnr temporarily as boolean indicating error.  */
 124                trapnr = (env->ir[IR_V0] != 0 && sysret < 0);
 125                env->ir[IR_V0] = (trapnr ? -sysret : sysret);
 126                env->ir[IR_A3] = trapnr;
 127                break;
 128            case 0x86:
 129                /* IMB */
 130                /* ??? We can probably elide the code using page_unprotect
 131                   that is checking for self-modifying code.  Instead we
 132                   could simply call tb_flush here.  Until we work out the
 133                   changes required to turn off the extra write protection,
 134                   this can be a no-op.  */
 135                break;
 136            case 0x9E:
 137                /* RDUNIQUE */
 138                /* Handled in the translator for usermode.  */
 139                abort();
 140            case 0x9F:
 141                /* WRUNIQUE */
 142                /* Handled in the translator for usermode.  */
 143                abort();
 144            case 0xAA:
 145                /* GENTRAP */
 146                info.si_signo = TARGET_SIGFPE;
 147                switch (env->ir[IR_A0]) {
 148                case TARGET_GEN_INTOVF:
 149                    info.si_code = TARGET_FPE_INTOVF;
 150                    break;
 151                case TARGET_GEN_INTDIV:
 152                    info.si_code = TARGET_FPE_INTDIV;
 153                    break;
 154                case TARGET_GEN_FLTOVF:
 155                    info.si_code = TARGET_FPE_FLTOVF;
 156                    break;
 157                case TARGET_GEN_FLTUND:
 158                    info.si_code = TARGET_FPE_FLTUND;
 159                    break;
 160                case TARGET_GEN_FLTINV:
 161                    info.si_code = TARGET_FPE_FLTINV;
 162                    break;
 163                case TARGET_GEN_FLTINE:
 164                    info.si_code = TARGET_FPE_FLTRES;
 165                    break;
 166                case TARGET_GEN_ROPRAND:
 167                    info.si_code = 0;
 168                    break;
 169                default:
 170                    info.si_signo = TARGET_SIGTRAP;
 171                    info.si_code = 0;
 172                    break;
 173                }
 174                info.si_errno = 0;
 175                info._sifields._sigfault._addr = env->pc;
 176                queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
 177                break;
 178            default:
 179                goto do_sigill;
 180            }
 181            break;
 182        case EXCP_DEBUG:
 183            info.si_signo = TARGET_SIGTRAP;
 184            info.si_errno = 0;
 185            info.si_code = TARGET_TRAP_BRKPT;
 186            queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
 187            break;
 188        case EXCP_INTERRUPT:
 189            /* Just indicate that signals should be handled asap.  */
 190            break;
 191        case EXCP_ATOMIC:
 192            cpu_exec_step_atomic(cs);
 193            arch_interrupt = false;
 194            break;
 195        default:
 196            fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
 197            cpu_dump_state(cs, stderr, 0);
 198            exit(EXIT_FAILURE);
 199        }
 200        process_pending_signals (env);
 201
 202        /* Most of the traps imply a transition through PALcode, which
 203           implies an REI instruction has been executed.  Which means
 204           that RX and LOCK_ADDR should be cleared.  But there are a
 205           few exceptions for traps internal to QEMU.  */
 206        if (arch_interrupt) {
 207            env->flags &= ~ENV_FLAG_RX_FLAG;
 208            env->lock_addr = -1;
 209        }
 210    }
 211}
 212
 213void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
 214{
 215    int i;
 216
 217    for(i = 0; i < 28; i++) {
 218        env->ir[i] = ((abi_ulong *)regs)[i];
 219    }
 220    env->ir[IR_SP] = regs->usp;
 221    env->pc = regs->pc;
 222}
 223