1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * QEMU LoongArch user cpu_loop.
4 *
5 * Copyright (c) 2021 Loongson Technology Corporation Limited
6 */
7
8 #include "qemu/osdep.h"
9 #include "qemu.h"
10 #include "user-internals.h"
11 #include "cpu_loop-common.h"
12 #include "signal-common.h"
13
cpu_loop(CPULoongArchState * env)14 void cpu_loop(CPULoongArchState *env)
15 {
16 CPUState *cs = env_cpu(env);
17 int trapnr, si_code;
18 abi_long ret;
19
20 for (;;) {
21 cpu_exec_start(cs);
22 trapnr = cpu_exec(cs);
23 cpu_exec_end(cs);
24 process_queued_cpu_work(cs);
25
26 switch (trapnr) {
27 case EXCP_INTERRUPT:
28 /* just indicate that signals should be handled asap */
29 break;
30 case EXCCODE_SYS:
31 env->pc += 4;
32 ret = do_syscall(env, env->gpr[11],
33 env->gpr[4], env->gpr[5],
34 env->gpr[6], env->gpr[7],
35 env->gpr[8], env->gpr[9],
36 -1, -1);
37 if (ret == -QEMU_ERESTARTSYS) {
38 env->pc -= 4;
39 break;
40 }
41 if (ret == -QEMU_ESIGRETURN) {
42 /*
43 * Returning from a successful sigreturn syscall.
44 * Avoid clobbering register state.
45 */
46 break;
47 }
48 env->gpr[4] = ret;
49 break;
50 case EXCCODE_INE:
51 force_sig_fault(TARGET_SIGILL, 0, env->pc);
52 break;
53 case EXCCODE_FPE:
54 si_code = TARGET_FPE_FLTUNK;
55 if (GET_FP_CAUSE(env->fcsr0) & FP_INVALID) {
56 si_code = TARGET_FPE_FLTINV;
57 } else if (GET_FP_CAUSE(env->fcsr0) & FP_DIV0) {
58 si_code = TARGET_FPE_FLTDIV;
59 } else if (GET_FP_CAUSE(env->fcsr0) & FP_OVERFLOW) {
60 si_code = TARGET_FPE_FLTOVF;
61 } else if (GET_FP_CAUSE(env->fcsr0) & FP_UNDERFLOW) {
62 si_code = TARGET_FPE_FLTUND;
63 } else if (GET_FP_CAUSE(env->fcsr0) & FP_INEXACT) {
64 si_code = TARGET_FPE_FLTRES;
65 }
66 force_sig_fault(TARGET_SIGFPE, si_code, env->pc);
67 break;
68 case EXCP_DEBUG:
69 case EXCCODE_BRK:
70 force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->pc);
71 break;
72 case EXCCODE_BCE:
73 force_sig_fault(TARGET_SIGSYS, TARGET_SI_KERNEL, env->pc);
74 break;
75
76 /*
77 * Begin with LSX and LASX disabled, then enable on the first trap.
78 * In this way we can tell if the unit is in use. This is used to
79 * choose the layout of any signal frame.
80 */
81 case EXCCODE_SXD:
82 env->CSR_EUEN |= R_CSR_EUEN_SXE_MASK;
83 break;
84 case EXCCODE_ASXD:
85 env->CSR_EUEN |= R_CSR_EUEN_ASXE_MASK;
86 break;
87
88 case EXCP_ATOMIC:
89 cpu_exec_step_atomic(cs);
90 break;
91 default:
92 EXCP_DUMP(env, "qemu: unhandled CPU exception 0x%x - aborting\n",
93 trapnr);
94 exit(EXIT_FAILURE);
95 }
96 process_pending_signals(env);
97 }
98 }
99
target_cpu_copy_regs(CPUArchState * env,struct target_pt_regs * regs)100 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)
101 {
102 int i;
103
104 for (i = 0; i < 32; i++) {
105 env->gpr[i] = regs->regs[i];
106 }
107 env->pc = regs->csr.era;
108
109 }
110