xref: /openbmc/qemu/linux-user/aarch64/cpu_loop.c (revision 6016b7b4)
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 "user-internals.h"
24 #include "cpu_loop-common.h"
25 #include "signal-common.h"
26 #include "qemu/guest-random.h"
27 #include "semihosting/common-semi.h"
28 #include "target/arm/syndrome.h"
29 
30 #define get_user_code_u32(x, gaddr, env)                \
31     ({ abi_long __r = get_user_u32((x), (gaddr));       \
32         if (!__r && bswap_code(arm_sctlr_b(env))) {     \
33             (x) = bswap32(x);                           \
34         }                                               \
35         __r;                                            \
36     })
37 
38 #define get_user_code_u16(x, gaddr, env)                \
39     ({ abi_long __r = get_user_u16((x), (gaddr));       \
40         if (!__r && bswap_code(arm_sctlr_b(env))) {     \
41             (x) = bswap16(x);                           \
42         }                                               \
43         __r;                                            \
44     })
45 
46 #define get_user_data_u32(x, gaddr, env)                \
47     ({ abi_long __r = get_user_u32((x), (gaddr));       \
48         if (!__r && arm_cpu_bswap_data(env)) {          \
49             (x) = bswap32(x);                           \
50         }                                               \
51         __r;                                            \
52     })
53 
54 #define get_user_data_u16(x, gaddr, env)                \
55     ({ abi_long __r = get_user_u16((x), (gaddr));       \
56         if (!__r && arm_cpu_bswap_data(env)) {          \
57             (x) = bswap16(x);                           \
58         }                                               \
59         __r;                                            \
60     })
61 
62 #define put_user_data_u32(x, gaddr, env)                \
63     ({ typeof(x) __x = (x);                             \
64         if (arm_cpu_bswap_data(env)) {                  \
65             __x = bswap32(__x);                         \
66         }                                               \
67         put_user_u32(__x, (gaddr));                     \
68     })
69 
70 #define put_user_data_u16(x, gaddr, env)                \
71     ({ typeof(x) __x = (x);                             \
72         if (arm_cpu_bswap_data(env)) {                  \
73             __x = bswap16(__x);                         \
74         }                                               \
75         put_user_u16(__x, (gaddr));                     \
76     })
77 
78 /* AArch64 main loop */
79 void cpu_loop(CPUARMState *env)
80 {
81     CPUState *cs = env_cpu(env);
82     int trapnr, ec, fsc, si_code, si_signo;
83     abi_long ret;
84 
85     for (;;) {
86         cpu_exec_start(cs);
87         trapnr = cpu_exec(cs);
88         cpu_exec_end(cs);
89         process_queued_cpu_work(cs);
90 
91         switch (trapnr) {
92         case EXCP_SWI:
93             ret = do_syscall(env,
94                              env->xregs[8],
95                              env->xregs[0],
96                              env->xregs[1],
97                              env->xregs[2],
98                              env->xregs[3],
99                              env->xregs[4],
100                              env->xregs[5],
101                              0, 0);
102             if (ret == -QEMU_ERESTARTSYS) {
103                 env->pc -= 4;
104             } else if (ret != -QEMU_ESIGRETURN) {
105                 env->xregs[0] = ret;
106             }
107             break;
108         case EXCP_INTERRUPT:
109             /* just indicate that signals should be handled asap */
110             break;
111         case EXCP_UDEF:
112             force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPN, env->pc);
113             break;
114         case EXCP_PREFETCH_ABORT:
115         case EXCP_DATA_ABORT:
116             ec = syn_get_ec(env->exception.syndrome);
117             switch (ec) {
118             case EC_DATAABORT:
119             case EC_INSNABORT:
120                 /* Both EC have the same format for FSC, or close enough. */
121                 fsc = extract32(env->exception.syndrome, 0, 6);
122                 switch (fsc) {
123                 case 0x04 ... 0x07: /* Translation fault, level {0-3} */
124                     si_signo = TARGET_SIGSEGV;
125                     si_code = TARGET_SEGV_MAPERR;
126                     break;
127                 case 0x09 ... 0x0b: /* Access flag fault, level {1-3} */
128                 case 0x0d ... 0x0f: /* Permission fault, level {1-3} */
129                     si_signo = TARGET_SIGSEGV;
130                     si_code = TARGET_SEGV_ACCERR;
131                     break;
132                 case 0x11: /* Synchronous Tag Check Fault */
133                     si_signo = TARGET_SIGSEGV;
134                     si_code = TARGET_SEGV_MTESERR;
135                     break;
136                 case 0x21: /* Alignment fault */
137                     si_signo = TARGET_SIGBUS;
138                     si_code = TARGET_BUS_ADRALN;
139                     break;
140                 default:
141                     g_assert_not_reached();
142                 }
143                 break;
144             case EC_PCALIGNMENT:
145                 si_signo = TARGET_SIGBUS;
146                 si_code = TARGET_BUS_ADRALN;
147                 break;
148             default:
149                 g_assert_not_reached();
150             }
151             force_sig_fault(si_signo, si_code, env->exception.vaddress);
152             break;
153         case EXCP_DEBUG:
154         case EXCP_BKPT:
155             force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->pc);
156             break;
157         case EXCP_SEMIHOST:
158             env->xregs[0] = do_common_semihosting(cs);
159             env->pc += 4;
160             break;
161         case EXCP_YIELD:
162             /* nothing to do here for user-mode, just resume guest code */
163             break;
164         case EXCP_ATOMIC:
165             cpu_exec_step_atomic(cs);
166             break;
167         default:
168             EXCP_DUMP(env, "qemu: unhandled CPU exception 0x%x - aborting\n", trapnr);
169             abort();
170         }
171 
172         /* Check for MTE asynchronous faults */
173         if (unlikely(env->cp15.tfsr_el[0])) {
174             env->cp15.tfsr_el[0] = 0;
175             force_sig_fault(TARGET_SIGSEGV, TARGET_SEGV_MTEAERR, 0);
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