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 Nios2CPU *cpu = NIOS2_CPU(cs); 30 target_siginfo_t info; 31 int trapnr, ret; 32 33 for (;;) { 34 cpu_exec_start(cs); 35 trapnr = cpu_exec(cs); 36 cpu_exec_end(cs); 37 38 switch (trapnr) { 39 case EXCP_INTERRUPT: 40 /* just indicate that signals should be handled asap */ 41 break; 42 case EXCP_TRAP: 43 if (env->regs[R_AT] == 0) { 44 abi_long ret; 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 > 0xfffffffffffff000ULL); 59 env->regs[CR_ESTATUS] = env->regs[CR_STATUS]; 60 env->regs[CR_STATUS] &= ~0x3; 61 env->regs[R_EA] = env->regs[R_PC] + 4; 62 env->regs[R_PC] += 4; 63 break; 64 } else { 65 qemu_log_mask(CPU_LOG_INT, "\nTrap\n"); 66 67 env->regs[CR_ESTATUS] = env->regs[CR_STATUS]; 68 env->regs[CR_STATUS] &= ~0x3; 69 env->regs[R_EA] = env->regs[R_PC] + 4; 70 env->regs[R_PC] = cpu->exception_addr; 71 72 info.si_signo = TARGET_SIGTRAP; 73 info.si_errno = 0; 74 info.si_code = TARGET_TRAP_BRKPT; 75 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info); 76 break; 77 } 78 case EXCP_DEBUG: 79 info.si_signo = TARGET_SIGTRAP; 80 info.si_errno = 0; 81 info.si_code = TARGET_TRAP_BRKPT; 82 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info); 83 break; 84 case 0xaa: 85 switch (env->regs[R_PC]) { 86 /*case 0x1000:*/ /* TODO:__kuser_helper_version */ 87 case 0x1004: /* __kuser_cmpxchg */ 88 start_exclusive(); 89 if (env->regs[4] & 0x3) { 90 goto kuser_fail; 91 } 92 ret = get_user_u32(env->regs[2], env->regs[4]); 93 if (ret) { 94 end_exclusive(); 95 goto kuser_fail; 96 } 97 env->regs[2] -= env->regs[5]; 98 if (env->regs[2] == 0) { 99 put_user_u32(env->regs[6], env->regs[4]); 100 } 101 end_exclusive(); 102 env->regs[R_PC] = env->regs[R_RA]; 103 break; 104 /*case 0x1040:*/ /* TODO:__kuser_sigtramp */ 105 default: 106 ; 107 kuser_fail: 108 info.si_signo = TARGET_SIGSEGV; 109 info.si_errno = 0; 110 /* TODO: check env->error_code */ 111 info.si_code = TARGET_SEGV_MAPERR; 112 info._sifields._sigfault._addr = env->regs[R_PC]; 113 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info); 114 } 115 break; 116 default: 117 EXCP_DUMP(env, "\nqemu: unhandled CPU exception %#x - aborting\n", 118 trapnr); 119 abort(); 120 } 121 122 process_pending_signals(env); 123 } 124 } 125 126 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs) 127 { 128 env->regs[0] = 0; 129 env->regs[1] = regs->r1; 130 env->regs[2] = regs->r2; 131 env->regs[3] = regs->r3; 132 env->regs[4] = regs->r4; 133 env->regs[5] = regs->r5; 134 env->regs[6] = regs->r6; 135 env->regs[7] = regs->r7; 136 env->regs[8] = regs->r8; 137 env->regs[9] = regs->r9; 138 env->regs[10] = regs->r10; 139 env->regs[11] = regs->r11; 140 env->regs[12] = regs->r12; 141 env->regs[13] = regs->r13; 142 env->regs[14] = regs->r14; 143 env->regs[15] = regs->r15; 144 /* TODO: unsigned long orig_r2; */ 145 env->regs[R_RA] = regs->ra; 146 env->regs[R_FP] = regs->fp; 147 env->regs[R_SP] = regs->sp; 148 env->regs[R_GP] = regs->gp; 149 env->regs[CR_ESTATUS] = regs->estatus; 150 env->regs[R_EA] = regs->ea; 151 /* TODO: unsigned long orig_r7; */ 152 153 /* Emulate eret when starting thread. */ 154 env->regs[R_PC] = regs->ea; 155 } 156