xref: /openbmc/qemu/linux-user/hppa/cpu_loop.c (revision feb58e3b)
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 
26 static abi_ulong hppa_lws(CPUHPPAState *env)
27 {
28     CPUState *cs = env_cpu(env);
29     uint32_t which = env->gr[20];
30     abi_ulong addr = env->gr[26];
31     abi_ulong old = env->gr[25];
32     abi_ulong new = env->gr[24];
33     abi_ulong size, ret;
34 
35     switch (which) {
36     default:
37         return -TARGET_ENOSYS;
38 
39     case 0: /* elf32 atomic 32bit cmpxchg */
40         if ((addr & 3) || !access_ok(cs, VERIFY_WRITE, addr, 4)) {
41             return -TARGET_EFAULT;
42         }
43         old = tswap32(old);
44         new = tswap32(new);
45         ret = qatomic_cmpxchg((uint32_t *)g2h(cs, addr), old, new);
46         ret = tswap32(ret);
47         break;
48 
49     case 2: /* elf32 atomic "new" cmpxchg */
50         size = env->gr[23];
51         if (size >= 4) {
52             return -TARGET_ENOSYS;
53         }
54         if (((addr | old | new) & ((1 << size) - 1))
55             || !access_ok(cs, VERIFY_WRITE, addr, 1 << size)
56             || !access_ok(cs, VERIFY_READ, old, 1 << size)
57             || !access_ok(cs, VERIFY_READ, new, 1 << size)) {
58             return -TARGET_EFAULT;
59         }
60         /* Note that below we use host-endian loads so that the cmpxchg
61            can be host-endian as well.  */
62         switch (size) {
63         case 0:
64             old = *(uint8_t *)g2h(cs, old);
65             new = *(uint8_t *)g2h(cs, new);
66             ret = qatomic_cmpxchg((uint8_t *)g2h(cs, addr), old, new);
67             ret = ret != old;
68             break;
69         case 1:
70             old = *(uint16_t *)g2h(cs, old);
71             new = *(uint16_t *)g2h(cs, new);
72             ret = qatomic_cmpxchg((uint16_t *)g2h(cs, addr), old, new);
73             ret = ret != old;
74             break;
75         case 2:
76             old = *(uint32_t *)g2h(cs, old);
77             new = *(uint32_t *)g2h(cs, new);
78             ret = qatomic_cmpxchg((uint32_t *)g2h(cs, addr), old, new);
79             ret = ret != old;
80             break;
81         case 3:
82             {
83                 uint64_t o64, n64, r64;
84                 o64 = *(uint64_t *)g2h(cs, old);
85                 n64 = *(uint64_t *)g2h(cs, new);
86 #ifdef CONFIG_ATOMIC64
87                 r64 = qatomic_cmpxchg__nocheck((aligned_uint64_t *)g2h(cs, addr),
88                                                o64, n64);
89                 ret = r64 != o64;
90 #else
91                 start_exclusive();
92                 r64 = *(uint64_t *)g2h(cs, addr);
93                 ret = 1;
94                 if (r64 == o64) {
95                     *(uint64_t *)g2h(cs, addr) = n64;
96                     ret = 0;
97                 }
98                 end_exclusive();
99 #endif
100             }
101             break;
102         default:
103             g_assert_not_reached();
104         }
105         break;
106     }
107 
108     env->gr[28] = ret;
109     return 0;
110 }
111 
112 void cpu_loop(CPUHPPAState *env)
113 {
114     CPUState *cs = env_cpu(env);
115     abi_ulong ret;
116     int trapnr;
117 
118     while (1) {
119         cpu_exec_start(cs);
120         trapnr = cpu_exec(cs);
121         cpu_exec_end(cs);
122         process_queued_cpu_work(cs);
123 
124         switch (trapnr) {
125         case EXCP_SYSCALL:
126             ret = do_syscall(env, env->gr[20],
127                              env->gr[26], env->gr[25],
128                              env->gr[24], env->gr[23],
129                              env->gr[22], env->gr[21], 0, 0);
130             switch (ret) {
131             default:
132                 env->gr[28] = ret;
133                 /* We arrived here by faking the gateway page.  Return.  */
134                 env->iaoq_f = env->gr[31] | PRIV_USER;
135                 env->iaoq_b = env->iaoq_f + 4;
136                 break;
137             case -QEMU_ERESTARTSYS:
138             case -QEMU_ESIGRETURN:
139                 break;
140             }
141             break;
142         case EXCP_SYSCALL_LWS:
143             env->gr[21] = hppa_lws(env);
144             /* We arrived here by faking the gateway page.  Return.  */
145             env->iaoq_f = env->gr[31] | PRIV_USER;
146             env->iaoq_b = env->iaoq_f + 4;
147             break;
148         case EXCP_IMP:
149             force_sig_fault(TARGET_SIGSEGV, TARGET_SEGV_MAPERR, env->iaoq_f);
150             break;
151         case EXCP_ILL:
152             force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPC, env->iaoq_f);
153             break;
154         case EXCP_PRIV_OPR:
155             /* check for glibc ABORT_INSTRUCTION "iitlbp %r0,(%sr0, %r0)" */
156             if (env->cr[CR_IIR] == 0x04000000) {
157                 force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPC, env->iaoq_f);
158             } else {
159                 force_sig_fault(TARGET_SIGILL, TARGET_ILL_PRVOPC, env->iaoq_f);
160             }
161             break;
162         case EXCP_PRIV_REG:
163             force_sig_fault(TARGET_SIGILL, TARGET_ILL_PRVREG, env->iaoq_f);
164             break;
165         case EXCP_OVERFLOW:
166             force_sig_fault(TARGET_SIGFPE, TARGET_FPE_INTOVF, env->iaoq_f);
167             break;
168         case EXCP_COND:
169             force_sig_fault(TARGET_SIGFPE, TARGET_FPE_CONDTRAP, env->iaoq_f);
170             break;
171         case EXCP_ASSIST:
172             force_sig_fault(TARGET_SIGFPE, 0, env->iaoq_f);
173             break;
174         case EXCP_BREAK:
175             force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->iaoq_f);
176             break;
177         case EXCP_DEBUG:
178             force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->iaoq_f);
179             break;
180         case EXCP_INTERRUPT:
181             /* just indicate that signals should be handled asap */
182             break;
183         default:
184             EXCP_DUMP(env, "qemu: unhandled CPU exception 0x%x - aborting\n", trapnr);
185             abort();
186         }
187         process_pending_signals(env);
188     }
189 }
190 
191 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
192 {
193     int i;
194     for (i = 1; i < 32; i++) {
195         env->gr[i] = regs->gr[i];
196     }
197     env->iaoq_f = regs->iaoq[0];
198     env->iaoq_b = regs->iaoq[1];
199 }
200