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-common.h"
  22#include "qemu.h"
  23#include "user-internals.h"
  24#include "cpu_loop-common.h"
  25#include "signal-common.h"
  26
  27void cpu_loop(CPUMBState *env)
  28{
  29    CPUState *cs = env_cpu(env);
  30    int trapnr, ret, si_code;
  31
  32    while (1) {
  33        cpu_exec_start(cs);
  34        trapnr = cpu_exec(cs);
  35        cpu_exec_end(cs);
  36        process_queued_cpu_work(cs);
  37
  38        switch (trapnr) {
  39        case EXCP_INTERRUPT:
  40            /* just indicate that signals should be handled asap */
  41            break;
  42        case EXCP_SYSCALL:
  43            /* Return address is 4 bytes after the call.  */
  44            env->regs[14] += 4;
  45            env->pc = env->regs[14];
  46            ret = do_syscall(env, 
  47                             env->regs[12], 
  48                             env->regs[5], 
  49                             env->regs[6], 
  50                             env->regs[7], 
  51                             env->regs[8], 
  52                             env->regs[9], 
  53                             env->regs[10],
  54                             0, 0);
  55            if (ret == -QEMU_ERESTARTSYS) {
  56                /* Wind back to before the syscall. */
  57                env->pc -= 4;
  58            } else if (ret != -QEMU_ESIGRETURN) {
  59                env->regs[3] = ret;
  60            }
  61            /* All syscall exits result in guest r14 being equal to the
  62             * PC we return to, because the kernel syscall exit "rtbd" does
  63             * this. (This is true even for sigreturn(); note that r14 is
  64             * not a userspace-usable register, as the kernel may clobber it
  65             * at any point.)
  66             */
  67            env->regs[14] = env->pc;
  68            break;
  69
  70        case EXCP_HW_EXCP:
  71            env->regs[17] = env->pc + 4;
  72            if (env->iflags & D_FLAG) {
  73                env->esr |= 1 << 12;
  74                env->pc -= 4;
  75                /* FIXME: if branch was immed, replay the imm as well.  */
  76            }
  77            env->iflags &= ~(IMM_FLAG | D_FLAG);
  78            switch (env->esr & 31) {
  79            case ESR_EC_DIVZERO:
  80                si_code = TARGET_FPE_INTDIV;
  81                break;
  82            case ESR_EC_FPU:
  83                /*
  84                 * Note that the kernel passes along fsr as si_code
  85                 * if there's no recognized bit set.  Possibly this
  86                 * implies that si_code is 0, but follow the structure.
  87                 */
  88                si_code = env->fsr;
  89                if (si_code & FSR_IO) {
  90                    si_code = TARGET_FPE_FLTINV;
  91                } else if (si_code & FSR_OF) {
  92                    si_code = TARGET_FPE_FLTOVF;
  93                } else if (si_code & FSR_UF) {
  94                    si_code = TARGET_FPE_FLTUND;
  95                } else if (si_code & FSR_DZ) {
  96                    si_code = TARGET_FPE_FLTDIV;
  97                } else if (si_code & FSR_DO) {
  98                    si_code = TARGET_FPE_FLTRES;
  99                }
 100                break;
 101            default:
 102                fprintf(stderr, "Unhandled hw-exception: 0x%x\n",
 103                        env->esr & ESR_EC_MASK);
 104                cpu_dump_state(cs, stderr, 0);
 105                exit(EXIT_FAILURE);
 106            }
 107            force_sig_fault(TARGET_SIGFPE, si_code, env->pc);
 108            break;
 109
 110        case EXCP_DEBUG:
 111            force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->pc);
 112            break;
 113        case EXCP_ATOMIC:
 114            cpu_exec_step_atomic(cs);
 115            break;
 116        default:
 117            fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
 118            cpu_dump_state(cs, stderr, 0);
 119            exit(EXIT_FAILURE);
 120        }
 121        process_pending_signals (env);
 122    }
 123}
 124
 125void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
 126{
 127    env->regs[0] = regs->r0;
 128    env->regs[1] = regs->r1;
 129    env->regs[2] = regs->r2;
 130    env->regs[3] = regs->r3;
 131    env->regs[4] = regs->r4;
 132    env->regs[5] = regs->r5;
 133    env->regs[6] = regs->r6;
 134    env->regs[7] = regs->r7;
 135    env->regs[8] = regs->r8;
 136    env->regs[9] = regs->r9;
 137    env->regs[10] = regs->r10;
 138    env->regs[11] = regs->r11;
 139    env->regs[12] = regs->r12;
 140    env->regs[13] = regs->r13;
 141    env->regs[14] = regs->r14;
 142    env->regs[15] = regs->r15;
 143    env->regs[16] = regs->r16;
 144    env->regs[17] = regs->r17;
 145    env->regs[18] = regs->r18;
 146    env->regs[19] = regs->r19;
 147    env->regs[20] = regs->r20;
 148    env->regs[21] = regs->r21;
 149    env->regs[22] = regs->r22;
 150    env->regs[23] = regs->r23;
 151    env->regs[24] = regs->r24;
 152    env->regs[25] = regs->r25;
 153    env->regs[26] = regs->r26;
 154    env->regs[27] = regs->r27;
 155    env->regs[28] = regs->r28;
 156    env->regs[29] = regs->r29;
 157    env->regs[30] = regs->r30;
 158    env->regs[31] = regs->r31;
 159    env->pc = regs->pc;
 160}
 161