xref: /openbmc/qemu/linux-user/hppa/cpu_loop.c (revision 5258a7e2)
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         }
103         break;
104     }
105 
106     env->gr[28] = ret;
107     return 0;
108 }
109 
110 void cpu_loop(CPUHPPAState *env)
111 {
112     CPUState *cs = env_cpu(env);
113     abi_ulong ret;
114     int trapnr;
115 
116     while (1) {
117         cpu_exec_start(cs);
118         trapnr = cpu_exec(cs);
119         cpu_exec_end(cs);
120         process_queued_cpu_work(cs);
121 
122         switch (trapnr) {
123         case EXCP_SYSCALL:
124             ret = do_syscall(env, env->gr[20],
125                              env->gr[26], env->gr[25],
126                              env->gr[24], env->gr[23],
127                              env->gr[22], env->gr[21], 0, 0);
128             switch (ret) {
129             default:
130                 env->gr[28] = ret;
131                 /* We arrived here by faking the gateway page.  Return.  */
132                 env->iaoq_f = env->gr[31];
133                 env->iaoq_b = env->gr[31] + 4;
134                 break;
135             case -QEMU_ERESTARTSYS:
136             case -QEMU_ESIGRETURN:
137                 break;
138             }
139             break;
140         case EXCP_SYSCALL_LWS:
141             env->gr[21] = hppa_lws(env);
142             /* We arrived here by faking the gateway page.  Return.  */
143             env->iaoq_f = env->gr[31];
144             env->iaoq_b = env->gr[31] + 4;
145             break;
146         case EXCP_IMP:
147             force_sig_fault(TARGET_SIGSEGV, TARGET_SEGV_MAPERR, env->iaoq_f);
148             break;
149         case EXCP_ILL:
150             force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPN, env->iaoq_f);
151             break;
152         case EXCP_PRIV_OPR:
153             force_sig_fault(TARGET_SIGILL, TARGET_ILL_PRVOPC, env->iaoq_f);
154             break;
155         case EXCP_PRIV_REG:
156             force_sig_fault(TARGET_SIGILL, TARGET_ILL_PRVREG, env->iaoq_f);
157             break;
158         case EXCP_OVERFLOW:
159             force_sig_fault(TARGET_SIGFPE, TARGET_FPE_INTOVF, env->iaoq_f);
160             break;
161         case EXCP_COND:
162             force_sig_fault(TARGET_SIGFPE, TARGET_FPE_CONDTRAP, env->iaoq_f);
163             break;
164         case EXCP_ASSIST:
165             force_sig_fault(TARGET_SIGFPE, 0, env->iaoq_f);
166             break;
167         case EXCP_DEBUG:
168             force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->iaoq_f);
169             break;
170         case EXCP_INTERRUPT:
171             /* just indicate that signals should be handled asap */
172             break;
173         default:
174             g_assert_not_reached();
175         }
176         process_pending_signals(env);
177     }
178 }
179 
180 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
181 {
182     int i;
183     for (i = 1; i < 32; i++) {
184         env->gr[i] = regs->gr[i];
185     }
186     env->iaoq_f = regs->iaoq[0];
187     env->iaoq_b = regs->iaoq[1];
188 }
189