xref: /openbmc/qemu/linux-user/hexagon/cpu_loop.c (revision b7bc6b18)
1 /*
2  *  qemu user cpu loop
3  *
4  *  Copyright (c) 2003-2008 Fabrice Bellard
5  *  Copyright(c) 2019-2021 Qualcomm Innovation Center, Inc. All Rights Reserved.
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License as published by
9  *  the Free Software Foundation; either version 2 of the License, or
10  *  (at your option) any later version.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
19  */
20 
21 #include "qemu/osdep.h"
22 #include "qemu.h"
23 #include "user-internals.h"
24 #include "cpu_loop-common.h"
25 #include "signal-common.h"
26 #include "internal.h"
27 
28 void cpu_loop(CPUHexagonState *env)
29 {
30     CPUState *cs = env_cpu(env);
31     int trapnr, signum, sigcode;
32     target_ulong sigaddr;
33     target_ulong syscallnum;
34     target_ulong ret;
35 
36     for (;;) {
37         cpu_exec_start(cs);
38         trapnr = cpu_exec(cs);
39         cpu_exec_end(cs);
40         process_queued_cpu_work(cs);
41 
42         signum = 0;
43         sigcode = 0;
44         sigaddr = 0;
45 
46         switch (trapnr) {
47         case EXCP_INTERRUPT:
48             /* just indicate that signals should be handled asap */
49             break;
50         case HEX_EXCP_TRAP0:
51             syscallnum = env->gpr[6];
52             env->gpr[HEX_REG_PC] += 4;
53             ret = do_syscall(env,
54                              syscallnum,
55                              env->gpr[0],
56                              env->gpr[1],
57                              env->gpr[2],
58                              env->gpr[3],
59                              env->gpr[4],
60                              env->gpr[5],
61                              0, 0);
62             if (ret == -TARGET_ERESTARTSYS) {
63                 env->gpr[HEX_REG_PC] -= 4;
64             } else if (ret != -TARGET_QEMU_ESIGRETURN) {
65                 env->gpr[0] = ret;
66             }
67             break;
68         case HEX_EXCP_FETCH_NO_UPAGE:
69         case HEX_EXCP_PRIV_NO_UREAD:
70         case HEX_EXCP_PRIV_NO_UWRITE:
71             signum = TARGET_SIGSEGV;
72             sigcode = TARGET_SEGV_MAPERR;
73             break;
74         case EXCP_ATOMIC:
75             cpu_exec_step_atomic(cs);
76             break;
77         default:
78             EXCP_DUMP(env, "\nqemu: unhandled CPU exception %#x - aborting\n",
79                      trapnr);
80             exit(EXIT_FAILURE);
81         }
82 
83         if (signum) {
84             target_siginfo_t info = {
85                 .si_signo = signum,
86                 .si_errno = 0,
87                 .si_code = sigcode,
88                 ._sifields._sigfault._addr = sigaddr
89             };
90             queue_signal(env, info.si_signo, QEMU_SI_KILL, &info);
91         }
92 
93         process_pending_signals(env);
94     }
95 }
96 
97 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
98 {
99     env->gpr[HEX_REG_PC] = regs->sepc;
100     env->gpr[HEX_REG_SP] = regs->sp;
101     env->gpr[HEX_REG_USR] = 0x56000;
102 }
103