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
cpu_loop(CPUNios2State * env)26 void cpu_loop(CPUNios2State *env)
27 {
28 CPUState *cs = env_cpu(env);
29 Nios2CPU *cpu = NIOS2_CPU(cs);
30 target_siginfo_t info;
31 int trapnr, ret;
32
33 for (;;) {
34 cpu_exec_start(cs);
35 trapnr = cpu_exec(cs);
36 cpu_exec_end(cs);
37
38 switch (trapnr) {
39 case EXCP_INTERRUPT:
40 /* just indicate that signals should be handled asap */
41 break;
42 case EXCP_TRAP:
43 if (env->regs[R_AT] == 0) {
44 abi_long ret;
45 qemu_log_mask(CPU_LOG_INT, "\nSyscall\n");
46
47 ret = do_syscall(env, env->regs[2],
48 env->regs[4], env->regs[5], env->regs[6],
49 env->regs[7], env->regs[8], env->regs[9],
50 0, 0);
51
52 if (env->regs[2] == 0) { /* FIXME: syscall 0 workaround */
53 ret = 0;
54 }
55
56 env->regs[2] = abs(ret);
57 /* Return value is 0..4096 */
58 env->regs[7] = (ret > 0xfffffffffffff000ULL);
59 env->regs[CR_ESTATUS] = env->regs[CR_STATUS];
60 env->regs[CR_STATUS] &= ~0x3;
61 env->regs[R_EA] = env->regs[R_PC] + 4;
62 env->regs[R_PC] += 4;
63 break;
64 } else {
65 qemu_log_mask(CPU_LOG_INT, "\nTrap\n");
66
67 env->regs[CR_ESTATUS] = env->regs[CR_STATUS];
68 env->regs[CR_STATUS] &= ~0x3;
69 env->regs[R_EA] = env->regs[R_PC] + 4;
70 env->regs[R_PC] = cpu->exception_addr;
71
72 info.si_signo = TARGET_SIGTRAP;
73 info.si_errno = 0;
74 info.si_code = TARGET_TRAP_BRKPT;
75 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
76 break;
77 }
78 case EXCP_DEBUG:
79 info.si_signo = TARGET_SIGTRAP;
80 info.si_errno = 0;
81 info.si_code = TARGET_TRAP_BRKPT;
82 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
83 break;
84 case 0xaa:
85 switch (env->regs[R_PC]) {
86 /*case 0x1000:*/ /* TODO:__kuser_helper_version */
87 case 0x1004: /* __kuser_cmpxchg */
88 start_exclusive();
89 if (env->regs[4] & 0x3) {
90 goto kuser_fail;
91 }
92 ret = get_user_u32(env->regs[2], env->regs[4]);
93 if (ret) {
94 end_exclusive();
95 goto kuser_fail;
96 }
97 env->regs[2] -= env->regs[5];
98 if (env->regs[2] == 0) {
99 put_user_u32(env->regs[6], env->regs[4]);
100 }
101 end_exclusive();
102 env->regs[R_PC] = env->regs[R_RA];
103 break;
104 /*case 0x1040:*/ /* TODO:__kuser_sigtramp */
105 default:
106 ;
107 kuser_fail:
108 info.si_signo = TARGET_SIGSEGV;
109 info.si_errno = 0;
110 /* TODO: check env->error_code */
111 info.si_code = TARGET_SEGV_MAPERR;
112 info._sifields._sigfault._addr = env->regs[R_PC];
113 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
114 }
115 break;
116 default:
117 EXCP_DUMP(env, "\nqemu: unhandled CPU exception %#x - aborting\n",
118 trapnr);
119 abort();
120 }
121
122 process_pending_signals(env);
123 }
124 }
125
target_cpu_copy_regs(CPUArchState * env,struct target_pt_regs * regs)126 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
127 {
128 env->regs[0] = 0;
129 env->regs[1] = regs->r1;
130 env->regs[2] = regs->r2;
131 env->regs[3] = regs->r3;
132 env->regs[4] = regs->r4;
133 env->regs[5] = regs->r5;
134 env->regs[6] = regs->r6;
135 env->regs[7] = regs->r7;
136 env->regs[8] = regs->r8;
137 env->regs[9] = regs->r9;
138 env->regs[10] = regs->r10;
139 env->regs[11] = regs->r11;
140 env->regs[12] = regs->r12;
141 env->regs[13] = regs->r13;
142 env->regs[14] = regs->r14;
143 env->regs[15] = regs->r15;
144 /* TODO: unsigned long orig_r2; */
145 env->regs[R_RA] = regs->ra;
146 env->regs[R_FP] = regs->fp;
147 env->regs[R_SP] = regs->sp;
148 env->regs[R_GP] = regs->gp;
149 env->regs[CR_ESTATUS] = regs->estatus;
150 env->regs[R_EA] = regs->ea;
151 /* TODO: unsigned long orig_r7; */
152
153 /* Emulate eret when starting thread. */
154 env->regs[R_PC] = regs->ea;
155 }
156