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(CPUMBState *env)
25 {
26     CPUState *cs = CPU(mb_env_get_cpu(env));
27     int trapnr, ret;
28     target_siginfo_t info;
29 
30     while (1) {
31         cpu_exec_start(cs);
32         trapnr = cpu_exec(cs);
33         cpu_exec_end(cs);
34         process_queued_cpu_work(cs);
35 
36         switch (trapnr) {
37         case 0xaa:
38             {
39                 info.si_signo = TARGET_SIGSEGV;
40                 info.si_errno = 0;
41                 /* XXX: check env->error_code */
42                 info.si_code = TARGET_SEGV_MAPERR;
43                 info._sifields._sigfault._addr = 0;
44                 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
45             }
46             break;
47         case EXCP_INTERRUPT:
48           /* just indicate that signals should be handled asap */
49           break;
50         case EXCP_BREAK:
51             /* Return address is 4 bytes after the call.  */
52             env->regs[14] += 4;
53             env->sregs[SR_PC] = env->regs[14];
54             ret = do_syscall(env,
55                              env->regs[12],
56                              env->regs[5],
57                              env->regs[6],
58                              env->regs[7],
59                              env->regs[8],
60                              env->regs[9],
61                              env->regs[10],
62                              0, 0);
63             if (ret == -TARGET_ERESTARTSYS) {
64                 /* Wind back to before the syscall. */
65                 env->sregs[SR_PC] -= 4;
66             } else if (ret != -TARGET_QEMU_ESIGRETURN) {
67                 env->regs[3] = ret;
68             }
69             /* All syscall exits result in guest r14 being equal to the
70              * PC we return to, because the kernel syscall exit "rtbd" does
71              * this. (This is true even for sigreturn(); note that r14 is
72              * not a userspace-usable register, as the kernel may clobber it
73              * at any point.)
74              */
75             env->regs[14] = env->sregs[SR_PC];
76             break;
77         case EXCP_HW_EXCP:
78             env->regs[17] = env->sregs[SR_PC] + 4;
79             if (env->iflags & D_FLAG) {
80                 env->sregs[SR_ESR] |= 1 << 12;
81                 env->sregs[SR_PC] -= 4;
82                 /* FIXME: if branch was immed, replay the imm as well.  */
83             }
84 
85             env->iflags &= ~(IMM_FLAG | D_FLAG);
86 
87             switch (env->sregs[SR_ESR] & 31) {
88                 case ESR_EC_DIVZERO:
89                     info.si_signo = TARGET_SIGFPE;
90                     info.si_errno = 0;
91                     info.si_code = TARGET_FPE_FLTDIV;
92                     info._sifields._sigfault._addr = 0;
93                     queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
94                     break;
95                 case ESR_EC_FPU:
96                     info.si_signo = TARGET_SIGFPE;
97                     info.si_errno = 0;
98                     if (env->sregs[SR_FSR] & FSR_IO) {
99                         info.si_code = TARGET_FPE_FLTINV;
100                     }
101                     if (env->sregs[SR_FSR] & FSR_DZ) {
102                         info.si_code = TARGET_FPE_FLTDIV;
103                     }
104                     info._sifields._sigfault._addr = 0;
105                     queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
106                     break;
107                 default:
108                     fprintf(stderr, "Unhandled hw-exception: 0x%" PRIx64 "\n",
109                             env->sregs[SR_ESR] & ESR_EC_MASK);
110                     cpu_dump_state(cs, stderr, 0);
111                     exit(EXIT_FAILURE);
112                     break;
113             }
114             break;
115         case EXCP_DEBUG:
116             info.si_signo = TARGET_SIGTRAP;
117             info.si_errno = 0;
118             info.si_code = TARGET_TRAP_BRKPT;
119             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
120             break;
121         case EXCP_ATOMIC:
122             cpu_exec_step_atomic(cs);
123             break;
124         default:
125             fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
126             cpu_dump_state(cs, stderr, 0);
127             exit(EXIT_FAILURE);
128         }
129         process_pending_signals (env);
130     }
131 }
132 
133 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
134 {
135     env->regs[0] = regs->r0;
136     env->regs[1] = regs->r1;
137     env->regs[2] = regs->r2;
138     env->regs[3] = regs->r3;
139     env->regs[4] = regs->r4;
140     env->regs[5] = regs->r5;
141     env->regs[6] = regs->r6;
142     env->regs[7] = regs->r7;
143     env->regs[8] = regs->r8;
144     env->regs[9] = regs->r9;
145     env->regs[10] = regs->r10;
146     env->regs[11] = regs->r11;
147     env->regs[12] = regs->r12;
148     env->regs[13] = regs->r13;
149     env->regs[14] = regs->r14;
150     env->regs[15] = regs->r15;
151     env->regs[16] = regs->r16;
152     env->regs[17] = regs->r17;
153     env->regs[18] = regs->r18;
154     env->regs[19] = regs->r19;
155     env->regs[20] = regs->r20;
156     env->regs[21] = regs->r21;
157     env->regs[22] = regs->r22;
158     env->regs[23] = regs->r23;
159     env->regs[24] = regs->r24;
160     env->regs[25] = regs->r25;
161     env->regs[26] = regs->r26;
162     env->regs[27] = regs->r27;
163     env->regs[28] = regs->r28;
164     env->regs[29] = regs->r29;
165     env->regs[30] = regs->r30;
166     env->regs[31] = regs->r31;
167     env->sregs[SR_PC] = regs->pc;
168 }
169