xref: /openbmc/qemu/linux-user/sh4/cpu_loop.c (revision 91654e61)
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(CPUSH4State *env)
28 {
29     CPUState *cs = env_cpu(env);
30     int trapnr, ret;
31 
32     while (1) {
33         bool arch_interrupt = true;
34 
35         cpu_exec_start(cs);
36         trapnr = cpu_exec(cs);
37         cpu_exec_end(cs);
38         process_queued_cpu_work(cs);
39 
40         switch (trapnr) {
41         case 0x160:
42             env->pc += 2;
43             ret = do_syscall(env,
44                              env->gregs[3],
45                              env->gregs[4],
46                              env->gregs[5],
47                              env->gregs[6],
48                              env->gregs[7],
49                              env->gregs[0],
50                              env->gregs[1],
51                              0, 0);
52             if (ret == -QEMU_ERESTARTSYS) {
53                 env->pc -= 2;
54             } else if (ret != -QEMU_ESIGRETURN) {
55                 env->gregs[0] = ret;
56             }
57             break;
58         case EXCP_INTERRUPT:
59             /* just indicate that signals should be handled asap */
60             break;
61         case EXCP_DEBUG:
62             force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->pc);
63             break;
64         case EXCP_ATOMIC:
65             cpu_exec_step_atomic(cs);
66             arch_interrupt = false;
67             break;
68         default:
69             fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
70             cpu_dump_state(cs, stderr, 0);
71             exit(EXIT_FAILURE);
72         }
73         process_pending_signals (env);
74 
75         /* Most of the traps imply an exception or interrupt, which
76            implies an REI instruction has been executed.  Which means
77            that LDST (aka LOK_ADDR) should be cleared.  But there are
78            a few exceptions for traps internal to QEMU.  */
79         if (arch_interrupt) {
80             env->lock_addr = -1;
81         }
82     }
83 }
84 
85 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
86 {
87     int i;
88 
89     for(i = 0; i < 16; i++) {
90         env->gregs[i] = regs->regs[i];
91     }
92     env->pc = regs->pc;
93 }
94