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/error-report.h" 22 #include "qemu.h" 23 #include "user-internals.h" 24 #include "cpu_loop-common.h" 25 #include "signal-common.h" 26 #include "elf.h" 27 #include "semihosting/common-semi.h" 28 29 void cpu_loop(CPURISCVState *env) 30 { 31 CPUState *cs = env_cpu(env); 32 int trapnr; 33 target_ulong ret; 34 35 for (;;) { 36 cpu_exec_start(cs); 37 trapnr = cpu_exec(cs); 38 cpu_exec_end(cs); 39 process_queued_cpu_work(cs); 40 41 switch (trapnr) { 42 case EXCP_INTERRUPT: 43 /* just indicate that signals should be handled asap */ 44 break; 45 case EXCP_ATOMIC: 46 cpu_exec_step_atomic(cs); 47 break; 48 case RISCV_EXCP_U_ECALL: 49 env->pc += 4; 50 if (env->gpr[xA7] == TARGET_NR_arch_specific_syscall + 15) { 51 /* riscv_flush_icache_syscall is a no-op in QEMU as 52 self-modifying code is automatically detected */ 53 ret = 0; 54 } else { 55 ret = do_syscall(env, 56 env->gpr[(env->elf_flags & EF_RISCV_RVE) 57 ? xT0 : xA7], 58 env->gpr[xA0], 59 env->gpr[xA1], 60 env->gpr[xA2], 61 env->gpr[xA3], 62 env->gpr[xA4], 63 env->gpr[xA5], 64 0, 0); 65 } 66 if (ret == -QEMU_ERESTARTSYS) { 67 env->pc -= 4; 68 } else if (ret != -QEMU_ESIGRETURN) { 69 env->gpr[xA0] = ret; 70 } 71 if (cs->singlestep_enabled) { 72 goto gdbstep; 73 } 74 break; 75 case RISCV_EXCP_ILLEGAL_INST: 76 force_sig_fault(TARGET_SIGILL, TARGET_ILL_ILLOPC, env->pc); 77 break; 78 case RISCV_EXCP_BREAKPOINT: 79 case EXCP_DEBUG: 80 gdbstep: 81 force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->pc); 82 break; 83 case RISCV_EXCP_SEMIHOST: 84 env->gpr[xA0] = do_common_semihosting(cs); 85 env->pc += 4; 86 break; 87 default: 88 EXCP_DUMP(env, "\nqemu: unhandled CPU exception %#x - aborting\n", 89 trapnr); 90 exit(EXIT_FAILURE); 91 } 92 93 process_pending_signals(env); 94 } 95 } 96 97 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs) 98 { 99 CPUState *cpu = env_cpu(env); 100 TaskState *ts = cpu->opaque; 101 struct image_info *info = ts->info; 102 103 env->pc = regs->sepc; 104 env->gpr[xSP] = regs->sp; 105 env->elf_flags = info->elf_flags; 106 107 if ((env->misa_ext & RVE) && !(env->elf_flags & EF_RISCV_RVE)) { 108 error_report("Incompatible ELF: RVE cpu requires RVE ABI binary"); 109 exit(EXIT_FAILURE); 110 } 111 112 ts->stack_base = info->start_stack; 113 ts->heap_base = info->brk; 114 /* This will be filled in on the first SYS_HEAPINFO call. */ 115 ts->heap_limit = 0; 116 } 117