xref: /openbmc/qemu/linux-user/aarch64/cpu_loop.c (revision e7bbc9b1)
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 "cpu_loop-common.h"
23 
24 #define get_user_code_u32(x, gaddr, env)                \
25     ({ abi_long __r = get_user_u32((x), (gaddr));       \
26         if (!__r && bswap_code(arm_sctlr_b(env))) {     \
27             (x) = bswap32(x);                           \
28         }                                               \
29         __r;                                            \
30     })
31 
32 #define get_user_code_u16(x, gaddr, env)                \
33     ({ abi_long __r = get_user_u16((x), (gaddr));       \
34         if (!__r && bswap_code(arm_sctlr_b(env))) {     \
35             (x) = bswap16(x);                           \
36         }                                               \
37         __r;                                            \
38     })
39 
40 #define get_user_data_u32(x, gaddr, env)                \
41     ({ abi_long __r = get_user_u32((x), (gaddr));       \
42         if (!__r && arm_cpu_bswap_data(env)) {          \
43             (x) = bswap32(x);                           \
44         }                                               \
45         __r;                                            \
46     })
47 
48 #define get_user_data_u16(x, gaddr, env)                \
49     ({ abi_long __r = get_user_u16((x), (gaddr));       \
50         if (!__r && arm_cpu_bswap_data(env)) {          \
51             (x) = bswap16(x);                           \
52         }                                               \
53         __r;                                            \
54     })
55 
56 #define put_user_data_u32(x, gaddr, env)                \
57     ({ typeof(x) __x = (x);                             \
58         if (arm_cpu_bswap_data(env)) {                  \
59             __x = bswap32(__x);                         \
60         }                                               \
61         put_user_u32(__x, (gaddr));                     \
62     })
63 
64 #define put_user_data_u16(x, gaddr, env)                \
65     ({ typeof(x) __x = (x);                             \
66         if (arm_cpu_bswap_data(env)) {                  \
67             __x = bswap16(__x);                         \
68         }                                               \
69         put_user_u16(__x, (gaddr));                     \
70     })
71 
72 /* AArch64 main loop */
73 void cpu_loop(CPUARMState *env)
74 {
75     CPUState *cs = CPU(arm_env_get_cpu(env));
76     int trapnr;
77     abi_long ret;
78     target_siginfo_t info;
79 
80     for (;;) {
81         cpu_exec_start(cs);
82         trapnr = cpu_exec(cs);
83         cpu_exec_end(cs);
84         process_queued_cpu_work(cs);
85 
86         switch (trapnr) {
87         case EXCP_SWI:
88             ret = do_syscall(env,
89                              env->xregs[8],
90                              env->xregs[0],
91                              env->xregs[1],
92                              env->xregs[2],
93                              env->xregs[3],
94                              env->xregs[4],
95                              env->xregs[5],
96                              0, 0);
97             if (ret == -TARGET_ERESTARTSYS) {
98                 env->pc -= 4;
99             } else if (ret != -TARGET_QEMU_ESIGRETURN) {
100                 env->xregs[0] = ret;
101             }
102             break;
103         case EXCP_INTERRUPT:
104             /* just indicate that signals should be handled asap */
105             break;
106         case EXCP_UDEF:
107             info.si_signo = TARGET_SIGILL;
108             info.si_errno = 0;
109             info.si_code = TARGET_ILL_ILLOPN;
110             info._sifields._sigfault._addr = env->pc;
111             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
112             break;
113         case EXCP_PREFETCH_ABORT:
114         case EXCP_DATA_ABORT:
115             info.si_signo = TARGET_SIGSEGV;
116             info.si_errno = 0;
117             /* XXX: check env->error_code */
118             info.si_code = TARGET_SEGV_MAPERR;
119             info._sifields._sigfault._addr = env->exception.vaddress;
120             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
121             break;
122         case EXCP_DEBUG:
123         case EXCP_BKPT:
124             info.si_signo = TARGET_SIGTRAP;
125             info.si_errno = 0;
126             info.si_code = TARGET_TRAP_BRKPT;
127             queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
128             break;
129         case EXCP_SEMIHOST:
130             env->xregs[0] = do_arm_semihosting(env);
131             break;
132         case EXCP_YIELD:
133             /* nothing to do here for user-mode, just resume guest code */
134             break;
135         case EXCP_ATOMIC:
136             cpu_exec_step_atomic(cs);
137             break;
138         default:
139             EXCP_DUMP(env, "qemu: unhandled CPU exception 0x%x - aborting\n", trapnr);
140             abort();
141         }
142         process_pending_signals(env);
143         /* Exception return on AArch64 always clears the exclusive monitor,
144          * so any return to running guest code implies this.
145          */
146         env->exclusive_addr = -1;
147     }
148 }
149 
150 static uint64_t arm_rand64(void)
151 {
152     int shift = 64 - clz64(RAND_MAX);
153     int i, n = 64 / shift + (64 % shift != 0);
154     uint64_t ret = 0;
155 
156     for (i = 0; i < n; i++) {
157         ret = (ret << shift) | rand();
158     }
159     return ret;
160 }
161 
162 void arm_init_pauth_key(ARMPACKey *key)
163 {
164     key->lo = arm_rand64();
165     key->hi = arm_rand64();
166 }
167 
168 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
169 {
170     ARMCPU *cpu = arm_env_get_cpu(env);
171     CPUState *cs = CPU(cpu);
172     TaskState *ts = cs->opaque;
173     struct image_info *info = ts->info;
174     int i;
175 
176     if (!(arm_feature(env, ARM_FEATURE_AARCH64))) {
177         fprintf(stderr,
178                 "The selected ARM CPU does not support 64 bit mode\n");
179         exit(EXIT_FAILURE);
180     }
181 
182     for (i = 0; i < 31; i++) {
183         env->xregs[i] = regs->regs[i];
184     }
185     env->pc = regs->pc;
186     env->xregs[31] = regs->sp;
187 #ifdef TARGET_WORDS_BIGENDIAN
188     env->cp15.sctlr_el[1] |= SCTLR_E0E;
189     for (i = 1; i < 4; ++i) {
190         env->cp15.sctlr_el[i] |= SCTLR_EE;
191     }
192 #endif
193 
194     if (cpu_isar_feature(aa64_pauth, cpu)) {
195         arm_init_pauth_key(&env->apia_key);
196         arm_init_pauth_key(&env->apib_key);
197         arm_init_pauth_key(&env->apda_key);
198         arm_init_pauth_key(&env->apdb_key);
199         arm_init_pauth_key(&env->apga_key);
200     }
201 
202     ts->stack_base = info->start_stack;
203     ts->heap_base = info->brk;
204     /* This will be filled in on the first SYS_HEAPINFO call.  */
205     ts->heap_limit = 0;
206 }
207