xref: /openbmc/qemu/linux-user/alpha/cpu_loop.c (revision f6476697)
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 "cpu_loop-common.h"
24 
25 void cpu_loop(CPUAlphaState *env)
26 {
27     CPUState *cs = env_cpu(env);
28     int trapnr;
29     target_siginfo_t info;
30     abi_long sysret;
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 EXCP_RESET:
42             fprintf(stderr, "Reset requested. Exit\n");
43             exit(EXIT_FAILURE);
44             break;
45         case EXCP_MCHK:
46             fprintf(stderr, "Machine check exception. Exit\n");
47             exit(EXIT_FAILURE);
48             break;
49         case EXCP_SMP_INTERRUPT:
50         case EXCP_CLK_INTERRUPT:
51         case EXCP_DEV_INTERRUPT:
52             fprintf(stderr, "External interrupt. Exit\n");
53             exit(EXIT_FAILURE);
54             break;
55         case EXCP_MMFAULT:
56             info.si_signo = TARGET_SIGSEGV;
57             info.si_errno = 0;
58             info.si_code = (page_get_flags(env->trap_arg0) & PAGE_VALID
59                             ? TARGET_SEGV_ACCERR : TARGET_SEGV_MAPERR);
60             info._sifields._sigfault._addr = env->trap_arg0;
61             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
62             break;
63         case EXCP_UNALIGN:
64             info.si_signo = TARGET_SIGBUS;
65             info.si_errno = 0;
66             info.si_code = TARGET_BUS_ADRALN;
67             info._sifields._sigfault._addr = env->trap_arg0;
68             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
69             break;
70         case EXCP_OPCDEC:
71         do_sigill:
72             info.si_signo = TARGET_SIGILL;
73             info.si_errno = 0;
74             info.si_code = TARGET_ILL_ILLOPC;
75             info._sifields._sigfault._addr = env->pc;
76             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
77             break;
78         case EXCP_ARITH:
79             info.si_signo = TARGET_SIGFPE;
80             info.si_errno = 0;
81             info.si_code = TARGET_FPE_FLTINV;
82             info._sifields._sigfault._addr = env->pc;
83             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
84             break;
85         case EXCP_FEN:
86             /* No-op.  Linux simply re-enables the FPU.  */
87             break;
88         case EXCP_CALL_PAL:
89             switch (env->error_code) {
90             case 0x80:
91                 /* BPT */
92                 info.si_signo = TARGET_SIGTRAP;
93                 info.si_errno = 0;
94                 info.si_code = TARGET_TRAP_BRKPT;
95                 info._sifields._sigfault._addr = env->pc;
96                 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
97                 break;
98             case 0x81:
99                 /* BUGCHK */
100                 info.si_signo = TARGET_SIGTRAP;
101                 info.si_errno = 0;
102                 info.si_code = 0;
103                 info._sifields._sigfault._addr = env->pc;
104                 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
105                 break;
106             case 0x83:
107                 /* CALLSYS */
108                 trapnr = env->ir[IR_V0];
109                 sysret = do_syscall(env, trapnr,
110                                     env->ir[IR_A0], env->ir[IR_A1],
111                                     env->ir[IR_A2], env->ir[IR_A3],
112                                     env->ir[IR_A4], env->ir[IR_A5],
113                                     0, 0);
114                 if (sysret == -TARGET_ERESTARTSYS) {
115                     env->pc -= 4;
116                     break;
117                 }
118                 if (sysret == -TARGET_QEMU_ESIGRETURN) {
119                     break;
120                 }
121                 /* Syscall writes 0 to V0 to bypass error check, similar
122                    to how this is handled internal to Linux kernel.
123                    (Ab)use trapnr temporarily as boolean indicating error.  */
124                 trapnr = (env->ir[IR_V0] != 0 && sysret < 0);
125                 env->ir[IR_V0] = (trapnr ? -sysret : sysret);
126                 env->ir[IR_A3] = trapnr;
127                 break;
128             case 0x86:
129                 /* IMB */
130                 /* ??? We can probably elide the code using page_unprotect
131                    that is checking for self-modifying code.  Instead we
132                    could simply call tb_flush here.  Until we work out the
133                    changes required to turn off the extra write protection,
134                    this can be a no-op.  */
135                 break;
136             case 0x9E:
137                 /* RDUNIQUE */
138                 /* Handled in the translator for usermode.  */
139                 abort();
140             case 0x9F:
141                 /* WRUNIQUE */
142                 /* Handled in the translator for usermode.  */
143                 abort();
144             case 0xAA:
145                 /* GENTRAP */
146                 info.si_signo = TARGET_SIGFPE;
147                 switch (env->ir[IR_A0]) {
148                 case TARGET_GEN_INTOVF:
149                     info.si_code = TARGET_FPE_INTOVF;
150                     break;
151                 case TARGET_GEN_INTDIV:
152                     info.si_code = TARGET_FPE_INTDIV;
153                     break;
154                 case TARGET_GEN_FLTOVF:
155                     info.si_code = TARGET_FPE_FLTOVF;
156                     break;
157                 case TARGET_GEN_FLTUND:
158                     info.si_code = TARGET_FPE_FLTUND;
159                     break;
160                 case TARGET_GEN_FLTINV:
161                     info.si_code = TARGET_FPE_FLTINV;
162                     break;
163                 case TARGET_GEN_FLTINE:
164                     info.si_code = TARGET_FPE_FLTRES;
165                     break;
166                 case TARGET_GEN_ROPRAND:
167                     info.si_code = 0;
168                     break;
169                 default:
170                     info.si_signo = TARGET_SIGTRAP;
171                     info.si_code = 0;
172                     break;
173                 }
174                 info.si_errno = 0;
175                 info._sifields._sigfault._addr = env->pc;
176                 queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
177                 break;
178             default:
179                 goto do_sigill;
180             }
181             break;
182         case EXCP_DEBUG:
183             info.si_signo = TARGET_SIGTRAP;
184             info.si_errno = 0;
185             info.si_code = TARGET_TRAP_BRKPT;
186             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
187             break;
188         case EXCP_INTERRUPT:
189             /* Just indicate that signals should be handled asap.  */
190             break;
191         case EXCP_ATOMIC:
192             cpu_exec_step_atomic(cs);
193             arch_interrupt = false;
194             break;
195         default:
196             fprintf(stderr, "Unhandled trap: 0x%x\n", trapnr);
197             cpu_dump_state(cs, stderr, 0);
198             exit(EXIT_FAILURE);
199         }
200         process_pending_signals (env);
201 
202         /* Most of the traps imply a transition through PALcode, which
203            implies an REI instruction has been executed.  Which means
204            that RX and LOCK_ADDR should be cleared.  But there are a
205            few exceptions for traps internal to QEMU.  */
206         if (arch_interrupt) {
207             env->flags &= ~ENV_FLAG_RX_FLAG;
208             env->lock_addr = -1;
209         }
210     }
211 }
212 
213 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
214 {
215     int i;
216 
217     for(i = 0; i < 28; i++) {
218         env->ir[i] = ((abi_ulong *)regs)[i];
219     }
220     env->ir[IR_SP] = regs->usp;
221     env->pc = regs->pc;
222 }
223