diff options
Diffstat (limited to 'target/arm/op_helper.c')
| -rw-r--r-- | target/arm/op_helper.c | 174 |
1 files changed, 17 insertions, 157 deletions
diff --git a/target/arm/op_helper.c b/target/arm/op_helper.c index ef72361a36..c998eadfaa 100644 --- a/target/arm/op_helper.c +++ b/target/arm/op_helper.c @@ -28,8 +28,8 @@ #define SIGNBIT (uint32_t)0x80000000 #define SIGNBIT64 ((uint64_t)1 << 63) -void raise_exception(CPUARMState *env, uint32_t excp, - uint32_t syndrome, uint32_t target_el) +static CPUState *do_raise_exception(CPUARMState *env, uint32_t excp, + uint32_t syndrome, uint32_t target_el) { CPUState *cs = CPU(arm_env_get_cpu(env)); @@ -50,9 +50,24 @@ void raise_exception(CPUARMState *env, uint32_t excp, cs->exception_index = excp; env->exception.syndrome = syndrome; env->exception.target_el = target_el; + + return cs; +} + +void raise_exception(CPUARMState *env, uint32_t excp, + uint32_t syndrome, uint32_t target_el) +{ + CPUState *cs = do_raise_exception(env, excp, syndrome, target_el); cpu_loop_exit(cs); } +void raise_exception_ra(CPUARMState *env, uint32_t excp, uint32_t syndrome, + uint32_t target_el, uintptr_t ra) +{ + CPUState *cs = do_raise_exception(env, excp, syndrome, target_el); + cpu_loop_exit_restore(cs, ra); +} + static int exception_target_el(CPUARMState *env) { int target_el = MAX(1, arm_current_el(env)); @@ -1014,161 +1029,6 @@ void HELPER(pre_smc)(CPUARMState *env, uint32_t syndrome) } } -static int el_from_spsr(uint32_t spsr) -{ - /* Return the exception level that this SPSR is requesting a return to, - * or -1 if it is invalid (an illegal return) - */ - if (spsr & PSTATE_nRW) { - switch (spsr & CPSR_M) { - case ARM_CPU_MODE_USR: - return 0; - case ARM_CPU_MODE_HYP: - return 2; - case ARM_CPU_MODE_FIQ: - case ARM_CPU_MODE_IRQ: - case ARM_CPU_MODE_SVC: - case ARM_CPU_MODE_ABT: - case ARM_CPU_MODE_UND: - case ARM_CPU_MODE_SYS: - return 1; - case ARM_CPU_MODE_MON: - /* Returning to Mon from AArch64 is never possible, - * so this is an illegal return. - */ - default: - return -1; - } - } else { - if (extract32(spsr, 1, 1)) { - /* Return with reserved M[1] bit set */ - return -1; - } - if (extract32(spsr, 0, 4) == 1) { - /* return to EL0 with M[0] bit set */ - return -1; - } - return extract32(spsr, 2, 2); - } -} - -void HELPER(exception_return)(CPUARMState *env) -{ - int cur_el = arm_current_el(env); - unsigned int spsr_idx = aarch64_banked_spsr_index(cur_el); - uint32_t spsr = env->banked_spsr[spsr_idx]; - int new_el; - bool return_to_aa64 = (spsr & PSTATE_nRW) == 0; - - aarch64_save_sp(env, cur_el); - - arm_clear_exclusive(env); - - /* We must squash the PSTATE.SS bit to zero unless both of the - * following hold: - * 1. debug exceptions are currently disabled - * 2. singlestep will be active in the EL we return to - * We check 1 here and 2 after we've done the pstate/cpsr write() to - * transition to the EL we're going to. - */ - if (arm_generate_debug_exceptions(env)) { - spsr &= ~PSTATE_SS; - } - - new_el = el_from_spsr(spsr); - if (new_el == -1) { - goto illegal_return; - } - if (new_el > cur_el - || (new_el == 2 && !arm_feature(env, ARM_FEATURE_EL2))) { - /* Disallow return to an EL which is unimplemented or higher - * than the current one. - */ - goto illegal_return; - } - - if (new_el != 0 && arm_el_is_aa64(env, new_el) != return_to_aa64) { - /* Return to an EL which is configured for a different register width */ - goto illegal_return; - } - - if (new_el == 2 && arm_is_secure_below_el3(env)) { - /* Return to the non-existent secure-EL2 */ - goto illegal_return; - } - - if (new_el == 1 && (arm_hcr_el2_eff(env) & HCR_TGE)) { - goto illegal_return; - } - - qemu_mutex_lock_iothread(); - arm_call_pre_el_change_hook(arm_env_get_cpu(env)); - qemu_mutex_unlock_iothread(); - - if (!return_to_aa64) { - env->aarch64 = 0; - /* We do a raw CPSR write because aarch64_sync_64_to_32() - * will sort the register banks out for us, and we've already - * caught all the bad-mode cases in el_from_spsr(). - */ - cpsr_write(env, spsr, ~0, CPSRWriteRaw); - if (!arm_singlestep_active(env)) { - env->uncached_cpsr &= ~PSTATE_SS; - } - aarch64_sync_64_to_32(env); - - if (spsr & CPSR_T) { - env->regs[15] = env->elr_el[cur_el] & ~0x1; - } else { - env->regs[15] = env->elr_el[cur_el] & ~0x3; - } - qemu_log_mask(CPU_LOG_INT, "Exception return from AArch64 EL%d to " - "AArch32 EL%d PC 0x%" PRIx32 "\n", - cur_el, new_el, env->regs[15]); - } else { - env->aarch64 = 1; - pstate_write(env, spsr); - if (!arm_singlestep_active(env)) { - env->pstate &= ~PSTATE_SS; - } - aarch64_restore_sp(env, new_el); - env->pc = env->elr_el[cur_el]; - qemu_log_mask(CPU_LOG_INT, "Exception return from AArch64 EL%d to " - "AArch64 EL%d PC 0x%" PRIx64 "\n", - cur_el, new_el, env->pc); - } - /* - * Note that cur_el can never be 0. If new_el is 0, then - * el0_a64 is return_to_aa64, else el0_a64 is ignored. - */ - aarch64_sve_change_el(env, cur_el, new_el, return_to_aa64); - - qemu_mutex_lock_iothread(); - arm_call_el_change_hook(arm_env_get_cpu(env)); - qemu_mutex_unlock_iothread(); - - return; - -illegal_return: - /* Illegal return events of various kinds have architecturally - * mandated behaviour: - * restore NZCV and DAIF from SPSR_ELx - * set PSTATE.IL - * restore PC from ELR_ELx - * no change to exception level, execution state or stack pointer - */ - env->pstate |= PSTATE_IL; - env->pc = env->elr_el[cur_el]; - spsr &= PSTATE_NZCV | PSTATE_DAIF; - spsr |= pstate_read(env) & ~(PSTATE_NZCV | PSTATE_DAIF); - pstate_write(env, spsr); - if (!arm_singlestep_active(env)) { - env->pstate &= ~PSTATE_SS; - } - qemu_log_mask(LOG_GUEST_ERROR, "Illegal exception return at EL%d: " - "resuming execution at 0x%" PRIx64 "\n", cur_el, env->pc); -} - /* Return true if the linked breakpoint entry lbn passes its checks */ static bool linked_bp_matches(ARMCPU *cpu, int lbn) { |