linux-user/nios2/cpu_loop.c

   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
  26 void cpu_loop(CPUNios2State *env)
  27 {
  28     CPUState *cs = env_cpu(env);
  29     target_siginfo_t info;
  30     int trapnr, ret;
  31
  32     for (;;) {
  33         cpu_exec_start(cs);
  34         trapnr = cpu_exec(cs);
  35         cpu_exec_end(cs);
  36
  37         switch (trapnr) {
  38         case EXCP_INTERRUPT:
  39             /* just indicate that signals should be handled asap */
  40             break;
  41
  42         case EXCP_TRAP:
  43             switch (env->error_code) {
  44             case 0:
  45                 qemu_log_mask(CPU_LOG_INT, "\nSyscall\n");
  46
  47                 ret = do_syscall(env, env->regs[2],
  48                                  env->regs[4], env->regs[5], env->regs[6],
  49                                  env->regs[7], env->regs[8], env->regs[9],
  50                                  0, 0);
  51
  52                 if (env->regs[2] == 0) {    /* FIXME: syscall 0 workaround */
  53                     ret = 0;
  54                 }
  55
  56                 env->regs[2] = abs(ret);
  57                 /* Return value is 0..4096 */
  58                 env->regs[7] = ret > 0xfffff000u;
  59                 env->regs[R_PC] += 4;
  60                 break;
  61
  62             case 1:
  63                 qemu_log_mask(CPU_LOG_INT, "\nTrap 1\n");
  64                 force_sig_fault(TARGET_SIGUSR1, 0, env->regs[R_PC]);
  65                 break;
  66             case 2:
  67                 qemu_log_mask(CPU_LOG_INT, "\nTrap 2\n");
  68                 force_sig_fault(TARGET_SIGUSR2, 0, env->regs[R_PC]);
  69                 break;
  70             case 31:
  71                 qemu_log_mask(CPU_LOG_INT, "\nTrap 31\n");
  72                 force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->regs[R_PC]);
  73                 break;
  74             default:
  75                 qemu_log_mask(CPU_LOG_INT, "\nTrap %d\n", env->error_code);
  76                 force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLTRP,
  77                                 env->regs[R_PC]);
  78                 break;
  79
  80             case 16: /* QEMU specific, for __kuser_cmpxchg */
  81                 {
  82                     abi_ptr g = env->regs[4];
  83                     uint32_t *h, n, o;
  84
  85                     if (g & 0x3) {
  86                         force_sig_fault(TARGET_SIGBUS, TARGET_BUS_ADRALN, g);
  87                         break;
  88                     }
  89                     ret = page_get_flags(g);
  90                     if (!(ret & PAGE_VALID)) {
  91                         force_sig_fault(TARGET_SIGSEGV, TARGET_SEGV_MAPERR, g);
  92                         break;
  93                     }
  94                     if (!(ret & PAGE_READ) || !(ret & PAGE_WRITE)) {
  95                         force_sig_fault(TARGET_SIGSEGV, TARGET_SEGV_ACCERR, g);
  96                         break;
  97                     }
  98                     h = g2h(cs, g);
  99                     o = env->regs[5];
 100                     n = env->regs[6];
 101                     env->regs[2] = qatomic_cmpxchg(h, o, n) - o;
 102                     env->regs[R_PC] += 4;
 103                 }
 104                 break;
 105             }
 106             break;
 107
 108         case EXCP_DEBUG:
 109             info.si_signo = TARGET_SIGTRAP;
 110             info.si_errno = 0;
 111             info.si_code = TARGET_TRAP_BRKPT;
 112             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
 113             break;
 114         case 0xaa:
 115             {
 116                 info.si_signo = TARGET_SIGSEGV;
 117                 info.si_errno = 0;
 118                 /* TODO: check env->error_code */
 119                 info.si_code = TARGET_SEGV_MAPERR;
 120                 info._sifields._sigfault._addr = env->regs[R_PC];
 121                 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
 122             }
 123             break;
 124         default:
 125             EXCP_DUMP(env, "\nqemu: unhandled CPU exception %#x - aborting\n",
 126                      trapnr);
 127             abort();
 128         }
 129
 130         process_pending_signals(env);
 131     }
 132 }
 133
 134 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
 135 {
 136     env->regs[0] = 0;
 137     env->regs[1] = regs->r1;
 138     env->regs[2] = regs->r2;
 139     env->regs[3] = regs->r3;
 140     env->regs[4] = regs->r4;
 141     env->regs[5] = regs->r5;
 142     env->regs[6] = regs->r6;
 143     env->regs[7] = regs->r7;
 144     env->regs[8] = regs->r8;
 145     env->regs[9] = regs->r9;
 146     env->regs[10] = regs->r10;
 147     env->regs[11] = regs->r11;
 148     env->regs[12] = regs->r12;
 149     env->regs[13] = regs->r13;
 150     env->regs[14] = regs->r14;
 151     env->regs[15] = regs->r15;
 152     /* TODO: unsigned long  orig_r2; */
 153     env->regs[R_RA] = regs->ra;
 154     env->regs[R_FP] = regs->fp;
 155     env->regs[R_SP] = regs->sp;
 156     env->regs[R_GP] = regs->gp;
 157     env->regs[CR_ESTATUS] = regs->estatus;
 158     env->regs[R_PC] = regs->ea;
 159     /* TODO: unsigned long  orig_r7; */
 160 }