xref: /openbmc/qemu/linux-user/aarch64/cpu_loop.c (revision 2a8af382)
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 #include "qemu/guest-random.h"
26 #include "semihosting/common-semi.h"
27 #include "target/arm/syndrome.h"
28 
29 #define get_user_code_u32(x, gaddr, env)                \
30     ({ abi_long __r = get_user_u32((x), (gaddr));       \
31         if (!__r && bswap_code(arm_sctlr_b(env))) {     \
32             (x) = bswap32(x);                           \
33         }                                               \
34         __r;                                            \
35     })
36 
37 #define get_user_code_u16(x, gaddr, env)                \
38     ({ abi_long __r = get_user_u16((x), (gaddr));       \
39         if (!__r && bswap_code(arm_sctlr_b(env))) {     \
40             (x) = bswap16(x);                           \
41         }                                               \
42         __r;                                            \
43     })
44 
45 #define get_user_data_u32(x, gaddr, env)                \
46     ({ abi_long __r = get_user_u32((x), (gaddr));       \
47         if (!__r && arm_cpu_bswap_data(env)) {          \
48             (x) = bswap32(x);                           \
49         }                                               \
50         __r;                                            \
51     })
52 
53 #define get_user_data_u16(x, gaddr, env)                \
54     ({ abi_long __r = get_user_u16((x), (gaddr));       \
55         if (!__r && arm_cpu_bswap_data(env)) {          \
56             (x) = bswap16(x);                           \
57         }                                               \
58         __r;                                            \
59     })
60 
61 #define put_user_data_u32(x, gaddr, env)                \
62     ({ typeof(x) __x = (x);                             \
63         if (arm_cpu_bswap_data(env)) {                  \
64             __x = bswap32(__x);                         \
65         }                                               \
66         put_user_u32(__x, (gaddr));                     \
67     })
68 
69 #define put_user_data_u16(x, gaddr, env)                \
70     ({ typeof(x) __x = (x);                             \
71         if (arm_cpu_bswap_data(env)) {                  \
72             __x = bswap16(__x);                         \
73         }                                               \
74         put_user_u16(__x, (gaddr));                     \
75     })
76 
77 /* AArch64 main loop */
78 void cpu_loop(CPUARMState *env)
79 {
80     CPUState *cs = env_cpu(env);
81     int trapnr, ec, fsc, si_code, si_signo;
82     abi_long ret;
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             /*
93              * On syscall, PSTATE.ZA is preserved, along with the ZA matrix.
94              * PSTATE.SM is cleared, per SMSTOP, which does ResetSVEState.
95              */
96             aarch64_set_svcr(env, 0, R_SVCR_SM_MASK);
97             if (FIELD_EX64(env->svcr, SVCR, SM)) {
98                 arm_rebuild_hflags(env);
99                 arm_reset_sve_state(env);
100             }
101             ret = do_syscall(env,
102                              env->xregs[8],
103                              env->xregs[0],
104                              env->xregs[1],
105                              env->xregs[2],
106                              env->xregs[3],
107                              env->xregs[4],
108                              env->xregs[5],
109                              0, 0);
110             if (ret == -QEMU_ERESTARTSYS) {
111                 env->pc -= 4;
112             } else if (ret != -QEMU_ESIGRETURN) {
113                 env->xregs[0] = ret;
114             }
115             break;
116         case EXCP_INTERRUPT:
117             /* just indicate that signals should be handled asap */
118             break;
119         case EXCP_UDEF:
120             force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPN, env->pc);
121             break;
122         case EXCP_PREFETCH_ABORT:
123         case EXCP_DATA_ABORT:
124             ec = syn_get_ec(env->exception.syndrome);
125             switch (ec) {
126             case EC_DATAABORT:
127             case EC_INSNABORT:
128                 /* Both EC have the same format for FSC, or close enough. */
129                 fsc = extract32(env->exception.syndrome, 0, 6);
130                 switch (fsc) {
131                 case 0x04 ... 0x07: /* Translation fault, level {0-3} */
132                     si_signo = TARGET_SIGSEGV;
133                     si_code = TARGET_SEGV_MAPERR;
134                     break;
135                 case 0x09 ... 0x0b: /* Access flag fault, level {1-3} */
136                 case 0x0d ... 0x0f: /* Permission fault, level {1-3} */
137                     si_signo = TARGET_SIGSEGV;
138                     si_code = TARGET_SEGV_ACCERR;
139                     break;
140                 case 0x11: /* Synchronous Tag Check Fault */
141                     si_signo = TARGET_SIGSEGV;
142                     si_code = TARGET_SEGV_MTESERR;
143                     break;
144                 case 0x21: /* Alignment fault */
145                     si_signo = TARGET_SIGBUS;
146                     si_code = TARGET_BUS_ADRALN;
147                     break;
148                 default:
149                     g_assert_not_reached();
150                 }
151                 break;
152             case EC_PCALIGNMENT:
153                 si_signo = TARGET_SIGBUS;
154                 si_code = TARGET_BUS_ADRALN;
155                 break;
156             default:
157                 g_assert_not_reached();
158             }
159             force_sig_fault(si_signo, si_code, env->exception.vaddress);
160             break;
161         case EXCP_DEBUG:
162         case EXCP_BKPT:
163             force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->pc);
164             break;
165         case EXCP_SEMIHOST:
166             do_common_semihosting(cs);
167             env->pc += 4;
168             break;
169         case EXCP_YIELD:
170             /* nothing to do here for user-mode, just resume guest code */
171             break;
172         case EXCP_ATOMIC:
173             cpu_exec_step_atomic(cs);
174             break;
175         default:
176             EXCP_DUMP(env, "qemu: unhandled CPU exception 0x%x - aborting\n", trapnr);
177             abort();
178         }
179 
180         /* Check for MTE asynchronous faults */
181         if (unlikely(env->cp15.tfsr_el[0])) {
182             env->cp15.tfsr_el[0] = 0;
183             force_sig_fault(TARGET_SIGSEGV, TARGET_SEGV_MTEAERR, 0);
184         }
185 
186         process_pending_signals(env);
187         /* Exception return on AArch64 always clears the exclusive monitor,
188          * so any return to running guest code implies this.
189          */
190         env->exclusive_addr = -1;
191     }
192 }
193 
194 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
195 {
196     ARMCPU *cpu = env_archcpu(env);
197     CPUState *cs = env_cpu(env);
198     TaskState *ts = cs->opaque;
199     struct image_info *info = ts->info;
200     int i;
201 
202     if (!(arm_feature(env, ARM_FEATURE_AARCH64))) {
203         fprintf(stderr,
204                 "The selected ARM CPU does not support 64 bit mode\n");
205         exit(EXIT_FAILURE);
206     }
207 
208     for (i = 0; i < 31; i++) {
209         env->xregs[i] = regs->regs[i];
210     }
211     env->pc = regs->pc;
212     env->xregs[31] = regs->sp;
213 #if TARGET_BIG_ENDIAN
214     env->cp15.sctlr_el[1] |= SCTLR_E0E;
215     for (i = 1; i < 4; ++i) {
216         env->cp15.sctlr_el[i] |= SCTLR_EE;
217     }
218     arm_rebuild_hflags(env);
219 #endif
220 
221     if (cpu_isar_feature(aa64_pauth, cpu)) {
222         qemu_guest_getrandom_nofail(&env->keys, sizeof(env->keys));
223     }
224 
225     ts->stack_base = info->start_stack;
226     ts->heap_base = info->brk;
227     /* This will be filled in on the first SYS_HEAPINFO call.  */
228     ts->heap_limit = 0;
229 }
230