xref: /openbmc/qemu/linux-user/m68k/cpu_loop.c (revision 79854b95)
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 
27 void cpu_loop(CPUM68KState *env)
28 {
29     CPUState *cs = env_cpu(env);
30     int trapnr;
31     unsigned int n;
32 
33     for(;;) {
34         cpu_exec_start(cs);
35         trapnr = cpu_exec(cs);
36         cpu_exec_end(cs);
37         process_queued_cpu_work(cs);
38 
39         switch(trapnr) {
40         case EXCP_HALT_INSN:
41             /* Semihosing syscall.  */
42             env->pc += 4;
43             do_m68k_semihosting(env, env->dregs[0]);
44             break;
45         case EXCP_ILLEGAL:
46         case EXCP_LINEA:
47         case EXCP_LINEF:
48             force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPN, env->pc);
49             break;
50         case EXCP_CHK:
51             force_sig_fault(TARGET_SIGFPE, TARGET_FPE_INTOVF, env->pc);
52             break;
53         case EXCP_DIV0:
54             force_sig_fault(TARGET_SIGFPE, TARGET_FPE_INTDIV, env->pc);
55             break;
56         case EXCP_TRAP0:
57             {
58                 abi_long ret;
59                 n = env->dregs[0];
60                 env->pc += 2;
61                 ret = do_syscall(env,
62                                  n,
63                                  env->dregs[1],
64                                  env->dregs[2],
65                                  env->dregs[3],
66                                  env->dregs[4],
67                                  env->dregs[5],
68                                  env->aregs[0],
69                                  0, 0);
70                 if (ret == -QEMU_ERESTARTSYS) {
71                     env->pc -= 2;
72                 } else if (ret != -QEMU_ESIGRETURN) {
73                     env->dregs[0] = ret;
74                 }
75             }
76             break;
77         case EXCP_INTERRUPT:
78             /* just indicate that signals should be handled asap */
79             break;
80         case EXCP_DEBUG:
81             force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->pc);
82             break;
83         case EXCP_ATOMIC:
84             cpu_exec_step_atomic(cs);
85             break;
86         default:
87             EXCP_DUMP(env, "qemu: unhandled CPU exception 0x%x - aborting\n", trapnr);
88             abort();
89         }
90         process_pending_signals(env);
91     }
92 }
93 
94 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
95 {
96     CPUState *cpu = env_cpu(env);
97     TaskState *ts = cpu->opaque;
98     struct image_info *info = ts->info;
99 
100     env->pc = regs->pc;
101     env->dregs[0] = regs->d0;
102     env->dregs[1] = regs->d1;
103     env->dregs[2] = regs->d2;
104     env->dregs[3] = regs->d3;
105     env->dregs[4] = regs->d4;
106     env->dregs[5] = regs->d5;
107     env->dregs[6] = regs->d6;
108     env->dregs[7] = regs->d7;
109     env->aregs[0] = regs->a0;
110     env->aregs[1] = regs->a1;
111     env->aregs[2] = regs->a2;
112     env->aregs[3] = regs->a3;
113     env->aregs[4] = regs->a4;
114     env->aregs[5] = regs->a5;
115     env->aregs[6] = regs->a6;
116     env->aregs[7] = regs->usp;
117     env->sr = regs->sr;
118 
119     ts->stack_base = info->start_stack;
120     ts->heap_base = info->brk;
121     /* This will be filled in on the first SYS_HEAPINFO call.  */
122     ts->heap_limit = 0;
123 }
124