1 /*
2  *  x86_64 cpu init and loop
3  *
4  *
5  *  This program is free software; you can redistribute it and/or modify
6  *  it under the terms of the GNU General Public License as published by
7  *  the Free Software Foundation; either version 2 of the License, or
8  *  (at your option) any later version.
9  *
10  *  This program is distributed in the hope that it will be useful,
11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *  GNU General Public License for more details.
14  *
15  *  You should have received a copy of the GNU General Public License
16  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
17  */
18 
19 #ifndef _TARGET_ARCH_CPU_H_
20 #define _TARGET_ARCH_CPU_H_
21 
22 #include "target_arch.h"
23 #include "signal-common.h"
24 
25 #define TARGET_DEFAULT_CPU_MODEL "qemu64"
26 
27 static inline void target_cpu_init(CPUX86State *env,
28         struct target_pt_regs *regs)
29 {
30     uint64_t *gdt_table;
31 
32     env->cr[0] = CR0_PG_MASK | CR0_WP_MASK | CR0_PE_MASK;
33     env->hflags |= HF_PE_MASK | HF_CPL_MASK;
34     if (env->features[FEAT_1_EDX] & CPUID_SSE) {
35         env->cr[4] |= CR4_OSFXSR_MASK;
36         env->hflags |= HF_OSFXSR_MASK;
37     }
38 
39     /* enable 64 bit mode if possible */
40     if (!(env->features[FEAT_8000_0001_EDX] & CPUID_EXT2_LM)) {
41         fprintf(stderr, "The selected x86 CPU does not support 64 bit mode\n");
42         exit(1);
43     }
44     env->cr[4] |= CR4_PAE_MASK;
45     env->efer |= MSR_EFER_LMA | MSR_EFER_LME;
46     env->hflags |= HF_LMA_MASK;
47 
48     /* flags setup : we activate the IRQs by default as in user mode */
49     env->eflags |= IF_MASK;
50 
51     /* register setup */
52     env->regs[R_EAX] = regs->rax;
53     env->regs[R_EBX] = regs->rbx;
54     env->regs[R_ECX] = regs->rcx;
55     env->regs[R_EDX] = regs->rdx;
56     env->regs[R_ESI] = regs->rsi;
57     env->regs[R_EDI] = regs->rdi;
58     env->regs[R_EBP] = regs->rbp;
59     env->regs[R_ESP] = regs->rsp;
60     env->eip = regs->rip;
61 
62     /* interrupt setup */
63     env->idt.limit = 511;
64 
65     env->idt.base = target_mmap(0, sizeof(uint64_t) * (env->idt.limit + 1),
66         PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
67     bsd_x86_64_set_idt_base(env->idt.base);
68     bsd_x86_64_set_idt(0, 0);
69     bsd_x86_64_set_idt(1, 0);
70     bsd_x86_64_set_idt(2, 0);
71     bsd_x86_64_set_idt(3, 3);
72     bsd_x86_64_set_idt(4, 3);
73     bsd_x86_64_set_idt(5, 0);
74     bsd_x86_64_set_idt(6, 0);
75     bsd_x86_64_set_idt(7, 0);
76     bsd_x86_64_set_idt(8, 0);
77     bsd_x86_64_set_idt(9, 0);
78     bsd_x86_64_set_idt(10, 0);
79     bsd_x86_64_set_idt(11, 0);
80     bsd_x86_64_set_idt(12, 0);
81     bsd_x86_64_set_idt(13, 0);
82     bsd_x86_64_set_idt(14, 0);
83     bsd_x86_64_set_idt(15, 0);
84     bsd_x86_64_set_idt(16, 0);
85     bsd_x86_64_set_idt(17, 0);
86     bsd_x86_64_set_idt(18, 0);
87     bsd_x86_64_set_idt(19, 0);
88     bsd_x86_64_set_idt(0x80, 3);
89 
90     /* segment setup */
91     env->gdt.base = target_mmap(0, sizeof(uint64_t) * TARGET_GDT_ENTRIES,
92             PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
93     env->gdt.limit = sizeof(uint64_t) * TARGET_GDT_ENTRIES - 1;
94     gdt_table = g2h_untagged(env->gdt.base);
95 
96     /* 64 bit code segment */
97     bsd_x86_64_write_dt(&gdt_table[__USER_CS >> 3], 0, 0xfffff,
98             DESC_G_MASK | DESC_B_MASK | DESC_P_MASK | DESC_S_MASK | DESC_L_MASK
99             | (3 << DESC_DPL_SHIFT) | (0xa << DESC_TYPE_SHIFT));
100 
101     bsd_x86_64_write_dt(&gdt_table[__USER_DS >> 3], 0, 0xfffff,
102             DESC_G_MASK | DESC_B_MASK | DESC_P_MASK | DESC_S_MASK |
103             (3 << DESC_DPL_SHIFT) | (0x2 << DESC_TYPE_SHIFT));
104 
105     cpu_x86_load_seg(env, R_CS, __USER_CS);
106     cpu_x86_load_seg(env, R_SS, __USER_DS);
107     cpu_x86_load_seg(env, R_DS, 0);
108     cpu_x86_load_seg(env, R_ES, 0);
109     cpu_x86_load_seg(env, R_FS, 0);
110     cpu_x86_load_seg(env, R_GS, 0);
111 }
112 
113 static inline void target_cpu_loop(CPUX86State *env)
114 {
115     CPUState *cs = env_cpu(env);
116     int trapnr;
117     abi_ulong pc;
118     /* target_siginfo_t info; */
119 
120     for (;;) {
121         cpu_exec_start(cs);
122         trapnr = cpu_exec(cs);
123         cpu_exec_end(cs);
124         process_queued_cpu_work(cs);
125 
126         switch (trapnr) {
127         case EXCP_SYSCALL:
128             /* syscall from syscall instruction */
129             env->regs[R_EAX] = do_freebsd_syscall(env,
130                                                   env->regs[R_EAX],
131                                                   env->regs[R_EDI],
132                                                   env->regs[R_ESI],
133                                                   env->regs[R_EDX],
134                                                   env->regs[R_ECX],
135                                                   env->regs[8],
136                                                   env->regs[9], 0, 0);
137             env->eip = env->exception_next_eip;
138             if (((abi_ulong)env->regs[R_EAX]) >= (abi_ulong)(-515)) {
139                 env->regs[R_EAX] = -env->regs[R_EAX];
140                 env->eflags |= CC_C;
141             } else {
142                 env->eflags &= ~CC_C;
143             }
144             break;
145 
146         case EXCP_INTERRUPT:
147             /* just indicate that signals should be handled asap */
148             break;
149 
150         case EXCP_ATOMIC:
151             cpu_exec_step_atomic(cs);
152             break;
153 
154         default:
155             pc = env->segs[R_CS].base + env->eip;
156             fprintf(stderr, "qemu: 0x%08lx: unhandled CPU exception 0x%x - "
157                     "aborting\n", (long)pc, trapnr);
158             abort();
159         }
160         process_pending_signals(env);
161     }
162 }
163 
164 static inline void target_cpu_clone_regs(CPUX86State *env, target_ulong newsp)
165 {
166     if (newsp) {
167         env->regs[R_ESP] = newsp;
168     }
169     env->regs[R_EAX] = 0;
170 }
171 
172 static inline void target_cpu_reset(CPUArchState *env)
173 {
174     cpu_reset(env_cpu(env));
175 }
176 
177 #endif /* ! _TARGET_ARCH_CPU_H_ */
178