xref: /openbmc/qemu/bsd-user/arm/target_arch_cpu.h (revision 588c7a17)
1 /*
2  *  arm cpu init and loop
3  *
4  *  Copyright (c) 2013 Stacey D. Son
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 #ifndef _TARGET_ARCH_CPU_H_
21 #define _TARGET_ARCH_CPU_H_
22 
23 #include "target_arch.h"
24 
25 #define TARGET_DEFAULT_CPU_MODEL "any"
26 
27 static inline void target_cpu_init(CPUARMState *env,
28         struct target_pt_regs *regs)
29 {
30     int i;
31 
32     cpsr_write(env, regs->uregs[16], CPSR_USER | CPSR_EXEC,
33                CPSRWriteByInstr);
34     for (i = 0; i < 16; i++) {
35         env->regs[i] = regs->uregs[i];
36     }
37 }
38 
39 static inline void target_cpu_loop(CPUARMState *env)
40 {
41     int trapnr;
42     target_siginfo_t info;
43     unsigned int n;
44     CPUState *cs = env_cpu(env);
45 
46     for (;;) {
47         cpu_exec_start(cs);
48         trapnr = cpu_exec(cs);
49         cpu_exec_end(cs);
50         process_queued_cpu_work(cs);
51         switch (trapnr) {
52         case EXCP_UDEF:
53             {
54                 /* See arm/arm/undefined.c undefinedinstruction(); */
55                 info.si_addr = env->regs[15];
56 
57                 /* illegal instruction */
58                 info.si_signo = TARGET_SIGILL;
59                 info.si_errno = 0;
60                 info.si_code = TARGET_ILL_ILLOPC;
61                 queue_signal(env, info.si_signo, &info);
62 
63                 /* TODO: What about instruction emulation? */
64             }
65             break;
66         case EXCP_SWI:
67         case EXCP_BKPT:
68             {
69                 /*
70                  * system call
71                  * See arm/arm/trap.c cpu_fetch_syscall_args()
72                  */
73                 if (trapnr == EXCP_BKPT) {
74                     if (env->thumb) {
75                         env->regs[15] += 2;
76                     } else {
77                         env->regs[15] += 4;
78                     }
79                 }
80                 n = env->regs[7];
81                 if (bsd_type == target_freebsd) {
82                     int ret;
83                     abi_ulong params = get_sp_from_cpustate(env);
84                     int32_t syscall_nr = n;
85                     int32_t arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8;
86 
87                     /* See arm/arm/trap.c cpu_fetch_syscall_args() */
88                     if (syscall_nr == TARGET_FREEBSD_NR_syscall) {
89                         syscall_nr = env->regs[0];
90                         arg1 = env->regs[1];
91                         arg2 = env->regs[2];
92                         arg3 = env->regs[3];
93                         get_user_s32(arg4, params);
94                         params += sizeof(int32_t);
95                         get_user_s32(arg5, params);
96                         params += sizeof(int32_t);
97                         get_user_s32(arg6, params);
98                         params += sizeof(int32_t);
99                         get_user_s32(arg7, params);
100                         arg8 = 0;
101                     } else if (syscall_nr == TARGET_FREEBSD_NR___syscall) {
102                         syscall_nr = env->regs[0];
103                         arg1 = env->regs[2];
104                         arg2 = env->regs[3];
105                         get_user_s32(arg3, params);
106                         params += sizeof(int32_t);
107                         get_user_s32(arg4, params);
108                         params += sizeof(int32_t);
109                         get_user_s32(arg5, params);
110                         params += sizeof(int32_t);
111                         get_user_s32(arg6, params);
112                         arg7 = 0;
113                         arg8 = 0;
114                     } else {
115                         arg1 = env->regs[0];
116                         arg2 = env->regs[1];
117                         arg3 = env->regs[2];
118                         arg4 = env->regs[3];
119                         get_user_s32(arg5, params);
120                         params += sizeof(int32_t);
121                         get_user_s32(arg6, params);
122                         params += sizeof(int32_t);
123                         get_user_s32(arg7, params);
124                         params += sizeof(int32_t);
125                         get_user_s32(arg8, params);
126                     }
127                     ret = do_freebsd_syscall(env, syscall_nr, arg1, arg2, arg3,
128                             arg4, arg5, arg6, arg7, arg8);
129                     /*
130                      * Compare to arm/arm/vm_machdep.c
131                      * cpu_set_syscall_retval()
132                      */
133                     if (-TARGET_EJUSTRETURN == ret) {
134                         /*
135                          * Returning from a successful sigreturn syscall.
136                          * Avoid clobbering register state.
137                          */
138                         break;
139                     }
140                     if (-TARGET_ERESTART == ret) {
141                         env->regs[15] -= env->thumb ? 2 : 4;
142                         break;
143                     }
144                     if ((unsigned int)ret >= (unsigned int)(-515)) {
145                         ret = -ret;
146                         cpsr_write(env, CPSR_C, CPSR_C, CPSRWriteByInstr);
147                         env->regs[0] = ret;
148                     } else {
149                         cpsr_write(env, 0, CPSR_C, CPSRWriteByInstr);
150                         env->regs[0] = ret; /* XXX need to handle lseek()? */
151                         /* env->regs[1] = 0; */
152                     }
153                 } else {
154                     fprintf(stderr, "qemu: bsd_type (= %d) syscall "
155                             "not supported\n", bsd_type);
156                 }
157             }
158             break;
159         case EXCP_INTERRUPT:
160             /* just indicate that signals should be handled asap */
161             break;
162         case EXCP_PREFETCH_ABORT:
163             /* See arm/arm/trap.c prefetch_abort_handler() */
164         case EXCP_DATA_ABORT:
165             /* See arm/arm/trap.c data_abort_handler() */
166             info.si_signo = TARGET_SIGSEGV;
167             info.si_errno = 0;
168             /* XXX: check env->error_code */
169             info.si_code = 0;
170             info.si_addr = env->exception.vaddress;
171             queue_signal(env, info.si_signo, &info);
172             break;
173         case EXCP_DEBUG:
174             {
175 
176                 info.si_signo = TARGET_SIGTRAP;
177                 info.si_errno = 0;
178                 info.si_code = TARGET_TRAP_BRKPT;
179                 info.si_addr = env->exception.vaddress;
180                 queue_signal(env, info.si_signo, &info);
181             }
182             break;
183         case EXCP_ATOMIC:
184             cpu_exec_step_atomic(cs);
185             break;
186         case EXCP_YIELD:
187             /* nothing to do here for user-mode, just resume guest code */
188             break;
189         default:
190             fprintf(stderr, "qemu: unhandled CPU exception 0x%x - aborting\n",
191                     trapnr);
192             cpu_dump_state(cs, stderr, 0);
193             abort();
194         } /* switch() */
195         process_pending_signals(env);
196     } /* for (;;) */
197 }
198 
199 static inline void target_cpu_clone_regs(CPUARMState *env, target_ulong newsp)
200 {
201     if (newsp) {
202         env->regs[13] = newsp;
203     }
204     env->regs[0] = 0;
205 }
206 
207 static inline void target_cpu_reset(CPUArchState *cpu)
208 {
209 }
210 
211 #endif /* !_TARGET_ARCH_CPU_H */
212