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 "cpu_loop-common.h" 23 24 void cpu_loop(CPUNios2State *env) 25 { 26 CPUState *cs = env_cpu(env); 27 Nios2CPU *cpu = NIOS2_CPU(cs); 28 target_siginfo_t info; 29 int trapnr, ret; 30 31 for (;;) { 32 cpu_exec_start(cs); 33 trapnr = cpu_exec(cs); 34 cpu_exec_end(cs); 35 36 switch (trapnr) { 37 case EXCP_INTERRUPT: 38 /* just indicate that signals should be handled asap */ 39 break; 40 case EXCP_TRAP: 41 if (env->regs[R_AT] == 0) { 42 abi_long ret; 43 qemu_log_mask(CPU_LOG_INT, "\nSyscall\n"); 44 45 ret = do_syscall(env, env->regs[2], 46 env->regs[4], env->regs[5], env->regs[6], 47 env->regs[7], env->regs[8], env->regs[9], 48 0, 0); 49 50 if (env->regs[2] == 0) { /* FIXME: syscall 0 workaround */ 51 ret = 0; 52 } 53 54 env->regs[2] = abs(ret); 55 /* Return value is 0..4096 */ 56 env->regs[7] = (ret > 0xfffffffffffff000ULL); 57 env->regs[CR_ESTATUS] = env->regs[CR_STATUS]; 58 env->regs[CR_STATUS] &= ~0x3; 59 env->regs[R_EA] = env->regs[R_PC] + 4; 60 env->regs[R_PC] += 4; 61 break; 62 } else { 63 qemu_log_mask(CPU_LOG_INT, "\nTrap\n"); 64 65 env->regs[CR_ESTATUS] = env->regs[CR_STATUS]; 66 env->regs[CR_STATUS] &= ~0x3; 67 env->regs[R_EA] = env->regs[R_PC] + 4; 68 env->regs[R_PC] = cpu->exception_addr; 69 70 info.si_signo = TARGET_SIGTRAP; 71 info.si_errno = 0; 72 info.si_code = TARGET_TRAP_BRKPT; 73 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info); 74 break; 75 } 76 case EXCP_DEBUG: 77 info.si_signo = TARGET_SIGTRAP; 78 info.si_errno = 0; 79 info.si_code = TARGET_TRAP_BRKPT; 80 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info); 81 break; 82 case 0xaa: 83 switch (env->regs[R_PC]) { 84 /*case 0x1000:*/ /* TODO:__kuser_helper_version */ 85 case 0x1004: /* __kuser_cmpxchg */ 86 start_exclusive(); 87 if (env->regs[4] & 0x3) { 88 goto kuser_fail; 89 } 90 ret = get_user_u32(env->regs[2], env->regs[4]); 91 if (ret) { 92 end_exclusive(); 93 goto kuser_fail; 94 } 95 env->regs[2] -= env->regs[5]; 96 if (env->regs[2] == 0) { 97 put_user_u32(env->regs[6], env->regs[4]); 98 } 99 end_exclusive(); 100 env->regs[R_PC] = env->regs[R_RA]; 101 break; 102 /*case 0x1040:*/ /* TODO:__kuser_sigtramp */ 103 default: 104 ; 105 kuser_fail: 106 info.si_signo = TARGET_SIGSEGV; 107 info.si_errno = 0; 108 /* TODO: check env->error_code */ 109 info.si_code = TARGET_SEGV_MAPERR; 110 info._sifields._sigfault._addr = env->regs[R_PC]; 111 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info); 112 } 113 break; 114 default: 115 EXCP_DUMP(env, "\nqemu: unhandled CPU exception %#x - aborting\n", 116 trapnr); 117 abort(); 118 } 119 120 process_pending_signals(env); 121 } 122 } 123 124 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs) 125 { 126 env->regs[0] = 0; 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 /* TODO: unsigned long orig_r2; */ 143 env->regs[R_RA] = regs->ra; 144 env->regs[R_FP] = regs->fp; 145 env->regs[R_SP] = regs->sp; 146 env->regs[R_GP] = regs->gp; 147 env->regs[CR_ESTATUS] = regs->estatus; 148 env->regs[R_EA] = regs->ea; 149 /* TODO: unsigned long orig_r7; */ 150 151 /* Emulate eret when starting thread. */ 152 env->regs[R_PC] = regs->ea; 153 } 154