LXR qemu/linux-user/microblaze/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.h"
  22#include "user-internals.h"
  23#include "cpu_loop-common.h"
  24#include "signal-common.h"
  25
  26void cpu_loop(CPUMBState *env)
  27{
  28    CPUState *cs = env_cpu(env);
  29    int trapnr, ret, si_code;
  30
  31    while (1) {
  32        cpu_exec_start(cs);
  33        trapnr = cpu_exec(cs);
  34        cpu_exec_end(cs);
  35        process_queued_cpu_work(cs);
  36
  37        switch (trapnr) {
  38        case EXCP_INTERRUPT:
  39            /* just indicate that signals should be handled asap */
  40            break;
  41        case EXCP_SYSCALL:
  42            /* Return address is 4 bytes after the call.  */
  43            env->regs[14] += 4;
  44            env->pc = env->regs[14];
  45            ret = do_syscall(env, 
  46                             env->regs[12], 
  47                             env->regs[5], 
  48                             env->regs[6], 
  49                             env->regs[7], 
  50                             env->regs[8], 
  51                             env->regs[9], 
  52                             env->regs[10],
  53                             0, 0);
  54            if (ret == -QEMU_ERESTARTSYS) {
  55                /* Wind back to before the syscall. */
  56                env->pc -= 4;
  57            } else if (ret != -QEMU_ESIGRETURN) {
  58                env->regs[3] = ret;
  59            }
  60            /* All syscall exits result in guest r14 being equal to the
  61             * PC we return to, because the kernel syscall exit "rtbd" does
  62             * this. (This is true even for sigreturn(); note that r14 is
  63             * not a userspace-usable register, as the kernel may clobber it
  64             * at any point.)
  65             */
  66            env->regs[14] = env->pc;
  67            break;
  68
  69        case EXCP_HW_EXCP:
  70            env->regs[17] = env->pc + 4;
  71            if (env->iflags & D_FLAG) {
  72                env->esr |= 1 << 12;
  73                env->pc -= 4;
  74                /* FIXME: if branch was immed, replay the imm as well.  */
  75            }
  76            env->iflags &= ~(IMM_FLAG | D_FLAG);
  77            switch (env->esr & 31) {
  78            case ESR_EC_DIVZERO:
  79                si_code = TARGET_FPE_INTDIV;
  80                break;
  81            case ESR_EC_FPU:
  82                /*
  83                 * Note that the kernel passes along fsr as si_code
  84                 * if there's no recognized bit set.  Possibly this
  85                 * implies that si_code is 0, but follow the structure.
  86                 */
  87                si_code = env->fsr;
  88                if (si_code & FSR_IO) {
  89                    si_code = TARGET_FPE_FLTINV;
  90                } else if (si_code & FSR_OF) {
  91                    si_code = TARGET_FPE_FLTOVF;
  92                } else if (si_code & FSR_UF) {
  93                    si_code = TARGET_FPE_FLTUND;
  94                } else if (si_code & FSR_DZ) {
  95                    si_code = TARGET_FPE_FLTDIV;
  96                } else if (si_code & FSR_DO) {
  97                    si_code = TARGET_FPE_FLTRES;
  98                }
  99                break;
 100            default:
 101                fprintf(stderr, "Unhandled hw-exception: 0x%x\n",
 102                        env->esr & ESR_EC_MASK);
 103                cpu_dump_state(cs, stderr, 0);
 104                exit(EXIT_FAILURE);
 105            }
 106            force_sig_fault(TARGET_SIGFPE, si_code, env->pc);
 107            break;
 108
 109        case EXCP_DEBUG:
 110            force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->pc);
 111            break;
 112        case EXCP_ATOMIC:
 113            cpu_exec_step_atomic(cs);
 114            break;
 115        default:
 116            fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
 117            cpu_dump_state(cs, stderr, 0);
 118            exit(EXIT_FAILURE);
 119        }
 120        process_pending_signals (env);
 121    }
 122}
 123
 124void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
 125{
 126    env->regs[0] = regs->r0;
 127    env->regs[1] = regs->r1;
 128    env->regs[2] = regs->r2;
 129    env->regs[3] = regs->r3;
 130    env->regs[4] = regs->r4;
 131    env->regs[5] = regs->r5;
 132    env->regs[6] = regs->r6;
 133    env->regs[7] = regs->r7;
 134    env->regs[8] = regs->r8;
 135    env->regs[9] = regs->r9;
 136    env->regs[10] = regs->r10;
 137    env->regs[11] = regs->r11;
 138    env->regs[12] = regs->r12;
 139    env->regs[13] = regs->r13;
 140    env->regs[14] = regs->r14;
 141    env->regs[15] = regs->r15;
 142    env->regs[16] = regs->r16;
 143    env->regs[17] = regs->r17;
 144    env->regs[18] = regs->r18;
 145    env->regs[19] = regs->r19;
 146    env->regs[20] = regs->r20;
 147    env->regs[21] = regs->r21;
 148    env->regs[22] = regs->r22;
 149    env->regs[23] = regs->r23;
 150    env->regs[24] = regs->r24;
 151    env->regs[25] = regs->r25;
 152    env->regs[26] = regs->r26;
 153    env->regs[27] = regs->r27;
 154    env->regs[28] = regs->r28;
 155    env->regs[29] = regs->r29;
 156    env->regs[30] = regs->r30;
 157    env->regs[31] = regs->r31;
 158    env->pc = regs->pc;
 159}
 160