diff options
| author | Mark Corbin <mark@dibsco.co.uk> | 2024-09-17 01:51:04 +1000 |
|---|---|---|
| committer | Alistair Francis <alistair.francis@wdc.com> | 2024-10-02 15:11:52 +1000 |
| commit | 92c15617e148b627a387e9cee2c2d8f807c7e246 (patch) | |
| tree | 641aa73985d93b8176db269c160fc2632aeebd22 /bsd-user | |
| parent | 9d49b1c9edf829e571093088ddff0b73db3110c6 (diff) | |
bsd-user: Add RISC-V CPU execution loop and syscall handling
Implemented the RISC-V CPU execution loop, including handling various
exceptions and system calls. The loop continuously executes CPU
instructions,processes exceptions, and handles system calls by invoking
FreeBSD syscall handlers.
Signed-off-by: Mark Corbin <mark@dibsco.co.uk>
Signed-off-by: Ajeet Singh <itachis@FreeBSD.org>
Co-authored-by: Jessica Clarke <jrtc27@jrtc27.com>
Co-authored-by: Kyle Evans <kevans@FreeBSD.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20240916155119.14610-3-itachis@FreeBSD.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Diffstat (limited to 'bsd-user')
| -rw-r--r-- | bsd-user/riscv/target_arch_cpu.h | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/bsd-user/riscv/target_arch_cpu.h b/bsd-user/riscv/target_arch_cpu.h index f8d85e01ad..9c31d9dc4c 100644 --- a/bsd-user/riscv/target_arch_cpu.h +++ b/bsd-user/riscv/target_arch_cpu.h @@ -37,4 +37,98 @@ static inline void target_cpu_init(CPURISCVState *env, env->pc = regs->sepc; } +static inline void target_cpu_loop(CPURISCVState *env) +{ + CPUState *cs = env_cpu(env); + int trapnr; + abi_long ret; + unsigned int syscall_num; + int32_t signo, code; + + for (;;) { + cpu_exec_start(cs); + trapnr = cpu_exec(cs); + cpu_exec_end(cs); + process_queued_cpu_work(cs); + + signo = 0; + + switch (trapnr) { + case EXCP_INTERRUPT: + /* just indicate that signals should be handled asap */ + break; + case EXCP_ATOMIC: + cpu_exec_step_atomic(cs); + break; + case RISCV_EXCP_U_ECALL: + syscall_num = env->gpr[xT0]; + env->pc += TARGET_INSN_SIZE; + /* Compare to cpu_fetch_syscall_args() in riscv/riscv/trap.c */ + if (TARGET_FREEBSD_NR___syscall == syscall_num || + TARGET_FREEBSD_NR_syscall == syscall_num) { + ret = do_freebsd_syscall(env, + env->gpr[xA0], + env->gpr[xA1], + env->gpr[xA2], + env->gpr[xA3], + env->gpr[xA4], + env->gpr[xA5], + env->gpr[xA6], + env->gpr[xA7], + 0); + } else { + ret = do_freebsd_syscall(env, + syscall_num, + env->gpr[xA0], + env->gpr[xA1], + env->gpr[xA2], + env->gpr[xA3], + env->gpr[xA4], + env->gpr[xA5], + env->gpr[xA6], + env->gpr[xA7] + ); + } + + /* + * Compare to cpu_set_syscall_retval() in + * riscv/riscv/vm_machdep.c + */ + if (ret >= 0) { + env->gpr[xA0] = ret; + env->gpr[xT0] = 0; + } else if (ret == -TARGET_ERESTART) { + env->pc -= TARGET_INSN_SIZE; + } else if (ret != -TARGET_EJUSTRETURN) { + env->gpr[xA0] = -ret; + env->gpr[xT0] = 1; + } + break; + case RISCV_EXCP_ILLEGAL_INST: + signo = TARGET_SIGILL; + code = TARGET_ILL_ILLOPC; + break; + case RISCV_EXCP_BREAKPOINT: + signo = TARGET_SIGTRAP; + code = TARGET_TRAP_BRKPT; + break; + case EXCP_DEBUG: + signo = TARGET_SIGTRAP; + code = TARGET_TRAP_BRKPT; + break; + default: + fprintf(stderr, "qemu: unhandled CPU exception " + "0x%x - aborting\n", trapnr); + cpu_dump_state(cs, stderr, 0); + abort(); + } + + if (signo) { + force_sig_fault(signo, code, env->pc); + } + + process_pending_signals(env); + } +} + #endif /* TARGET_ARCH_CPU_H */ |