xref: /openbmc/qemu/linux-user/aarch64/cpu_loop.c (revision 0694dabe)
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 #include "qemu/guest-random.h"
25 #include "hw/semihosting/common-semi.h"
26 #include "target/arm/syndrome.h"
27 
28 #define get_user_code_u32(x, gaddr, env)                \
29     ({ abi_long __r = get_user_u32((x), (gaddr));       \
30         if (!__r && bswap_code(arm_sctlr_b(env))) {     \
31             (x) = bswap32(x);                           \
32         }                                               \
33         __r;                                            \
34     })
35 
36 #define get_user_code_u16(x, gaddr, env)                \
37     ({ abi_long __r = get_user_u16((x), (gaddr));       \
38         if (!__r && bswap_code(arm_sctlr_b(env))) {     \
39             (x) = bswap16(x);                           \
40         }                                               \
41         __r;                                            \
42     })
43 
44 #define get_user_data_u32(x, gaddr, env)                \
45     ({ abi_long __r = get_user_u32((x), (gaddr));       \
46         if (!__r && arm_cpu_bswap_data(env)) {          \
47             (x) = bswap32(x);                           \
48         }                                               \
49         __r;                                            \
50     })
51 
52 #define get_user_data_u16(x, gaddr, env)                \
53     ({ abi_long __r = get_user_u16((x), (gaddr));       \
54         if (!__r && arm_cpu_bswap_data(env)) {          \
55             (x) = bswap16(x);                           \
56         }                                               \
57         __r;                                            \
58     })
59 
60 #define put_user_data_u32(x, gaddr, env)                \
61     ({ typeof(x) __x = (x);                             \
62         if (arm_cpu_bswap_data(env)) {                  \
63             __x = bswap32(__x);                         \
64         }                                               \
65         put_user_u32(__x, (gaddr));                     \
66     })
67 
68 #define put_user_data_u16(x, gaddr, env)                \
69     ({ typeof(x) __x = (x);                             \
70         if (arm_cpu_bswap_data(env)) {                  \
71             __x = bswap16(__x);                         \
72         }                                               \
73         put_user_u16(__x, (gaddr));                     \
74     })
75 
76 /* AArch64 main loop */
77 void cpu_loop(CPUARMState *env)
78 {
79     CPUState *cs = env_cpu(env);
80     int trapnr, ec, fsc;
81     abi_long ret;
82     target_siginfo_t info;
83 
84     for (;;) {
85         cpu_exec_start(cs);
86         trapnr = cpu_exec(cs);
87         cpu_exec_end(cs);
88         process_queued_cpu_work(cs);
89 
90         switch (trapnr) {
91         case EXCP_SWI:
92             ret = do_syscall(env,
93                              env->xregs[8],
94                              env->xregs[0],
95                              env->xregs[1],
96                              env->xregs[2],
97                              env->xregs[3],
98                              env->xregs[4],
99                              env->xregs[5],
100                              0, 0);
101             if (ret == -TARGET_ERESTARTSYS) {
102                 env->pc -= 4;
103             } else if (ret != -TARGET_QEMU_ESIGRETURN) {
104                 env->xregs[0] = ret;
105             }
106             break;
107         case EXCP_INTERRUPT:
108             /* just indicate that signals should be handled asap */
109             break;
110         case EXCP_UDEF:
111             info.si_signo = TARGET_SIGILL;
112             info.si_errno = 0;
113             info.si_code = TARGET_ILL_ILLOPN;
114             info._sifields._sigfault._addr = env->pc;
115             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
116             break;
117         case EXCP_PREFETCH_ABORT:
118         case EXCP_DATA_ABORT:
119             info.si_signo = TARGET_SIGSEGV;
120             info.si_errno = 0;
121             info._sifields._sigfault._addr = env->exception.vaddress;
122 
123             /* We should only arrive here with EC in {DATAABORT, INSNABORT}. */
124             ec = syn_get_ec(env->exception.syndrome);
125             assert(ec == EC_DATAABORT || ec == EC_INSNABORT);
126 
127             /* Both EC have the same format for FSC, or close enough. */
128             fsc = extract32(env->exception.syndrome, 0, 6);
129             switch (fsc) {
130             case 0x04 ... 0x07: /* Translation fault, level {0-3} */
131                 info.si_code = TARGET_SEGV_MAPERR;
132                 break;
133             case 0x09 ... 0x0b: /* Access flag fault, level {1-3} */
134             case 0x0d ... 0x0f: /* Permission fault, level {1-3} */
135                 info.si_code = TARGET_SEGV_ACCERR;
136                 break;
137             case 0x11: /* Synchronous Tag Check Fault */
138                 info.si_code = TARGET_SEGV_MTESERR;
139                 break;
140             default:
141                 g_assert_not_reached();
142             }
143 
144             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
145             break;
146         case EXCP_DEBUG:
147         case EXCP_BKPT:
148             info.si_signo = TARGET_SIGTRAP;
149             info.si_errno = 0;
150             info.si_code = TARGET_TRAP_BRKPT;
151             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
152             break;
153         case EXCP_SEMIHOST:
154             env->xregs[0] = do_common_semihosting(cs);
155             env->pc += 4;
156             break;
157         case EXCP_YIELD:
158             /* nothing to do here for user-mode, just resume guest code */
159             break;
160         case EXCP_ATOMIC:
161             cpu_exec_step_atomic(cs);
162             break;
163         default:
164             EXCP_DUMP(env, "qemu: unhandled CPU exception 0x%x - aborting\n", trapnr);
165             abort();
166         }
167 
168         /* Check for MTE asynchronous faults */
169         if (unlikely(env->cp15.tfsr_el[0])) {
170             env->cp15.tfsr_el[0] = 0;
171             info.si_signo = TARGET_SIGSEGV;
172             info.si_errno = 0;
173             info._sifields._sigfault._addr = 0;
174             info.si_code = TARGET_SEGV_MTEAERR;
175             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
176         }
177 
178         process_pending_signals(env);
179         /* Exception return on AArch64 always clears the exclusive monitor,
180          * so any return to running guest code implies this.
181          */
182         env->exclusive_addr = -1;
183     }
184 }
185 
186 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
187 {
188     ARMCPU *cpu = env_archcpu(env);
189     CPUState *cs = env_cpu(env);
190     TaskState *ts = cs->opaque;
191     struct image_info *info = ts->info;
192     int i;
193 
194     if (!(arm_feature(env, ARM_FEATURE_AARCH64))) {
195         fprintf(stderr,
196                 "The selected ARM CPU does not support 64 bit mode\n");
197         exit(EXIT_FAILURE);
198     }
199 
200     for (i = 0; i < 31; i++) {
201         env->xregs[i] = regs->regs[i];
202     }
203     env->pc = regs->pc;
204     env->xregs[31] = regs->sp;
205 #ifdef TARGET_WORDS_BIGENDIAN
206     env->cp15.sctlr_el[1] |= SCTLR_E0E;
207     for (i = 1; i < 4; ++i) {
208         env->cp15.sctlr_el[i] |= SCTLR_EE;
209     }
210     arm_rebuild_hflags(env);
211 #endif
212 
213     if (cpu_isar_feature(aa64_pauth, cpu)) {
214         qemu_guest_getrandom_nofail(&env->keys, sizeof(env->keys));
215     }
216 
217     ts->stack_base = info->start_stack;
218     ts->heap_base = info->brk;
219     /* This will be filled in on the first SYS_HEAPINFO call.  */
220     ts->heap_limit = 0;
221 }
222