xref: /openbmc/qemu/linux-user/sh4/cpu_loop.c (revision 4921d0a7)
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(CPUSH4State *env)
27 {
28     CPUState *cs = env_cpu(env);
29     int trapnr, ret;
30 
31     while (1) {
32         bool arch_interrupt = true;
33 
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 0x160:
41             env->pc += 2;
42             ret = do_syscall(env,
43                              env->gregs[3],
44                              env->gregs[4],
45                              env->gregs[5],
46                              env->gregs[6],
47                              env->gregs[7],
48                              env->gregs[0],
49                              env->gregs[1],
50                              0, 0);
51             if (ret == -QEMU_ERESTARTSYS) {
52                 env->pc -= 2;
53             } else if (ret != -QEMU_ESIGRETURN) {
54                 env->gregs[0] = ret;
55             }
56             break;
57         case EXCP_INTERRUPT:
58             /* just indicate that signals should be handled asap */
59             break;
60         case EXCP_DEBUG:
61             force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->pc);
62             break;
63         case EXCP_ATOMIC:
64             cpu_exec_step_atomic(cs);
65             arch_interrupt = false;
66             break;
67         default:
68             fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
69             cpu_dump_state(cs, stderr, 0);
70             exit(EXIT_FAILURE);
71         }
72         process_pending_signals (env);
73 
74         /* Most of the traps imply an exception or interrupt, which
75            implies an REI instruction has been executed.  Which means
76            that LDST (aka LOK_ADDR) should be cleared.  But there are
77            a few exceptions for traps internal to QEMU.  */
78         if (arch_interrupt) {
79             env->lock_addr = -1;
80         }
81     }
82 }
83 
84 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
85 {
86     int i;
87 
88     for(i = 0; i < 16; i++) {
89         env->gregs[i] = regs->regs[i];
90     }
91     env->pc = regs->pc;
92 }
93