Implement the necessary support code for taking exceptions to Hyp mode in AArch32.
Signed-off-by: Peter Maydell <peter.mayd...@linaro.org> --- target/arm/helper.c | 146 +++++++++++++++++++++++++++++++++++++------- 1 file changed, 123 insertions(+), 23 deletions(-) diff --git a/target/arm/helper.c b/target/arm/helper.c index 80855302089..167203ac664 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -8013,6 +8013,123 @@ void aarch64_sync_64_to_32(CPUARMState *env) env->regs[15] = env->pc; } +static void take_aarch32_exception(CPUARMState *env, int new_mode, + uint32_t mask, uint32_t offset, + uint32_t newpc) +{ + /* Change the CPU state so as to actually take the exception. */ + switch_mode(env, new_mode); + /* + * For exceptions taken to AArch32 we must clear the SS bit in both + * PSTATE and in the old-state value we save to SPSR_<mode>, so zero it now. + */ + env->uncached_cpsr &= ~PSTATE_SS; + env->spsr = cpsr_read(env); + /* Clear IT bits. */ + env->condexec_bits = 0; + /* Switch to the new mode, and to the correct instruction set. */ + env->uncached_cpsr = (env->uncached_cpsr & ~CPSR_M) | new_mode; + /* Set new mode endianness */ + env->uncached_cpsr &= ~CPSR_E; + if (env->cp15.sctlr_el[arm_current_el(env)] & SCTLR_EE) { + env->uncached_cpsr |= CPSR_E; + } + env->daif |= mask; + + if (new_mode == ARM_CPU_MODE_HYP) { + env->thumb = (env->cp15.sctlr_el[2] & SCTLR_TE) != 0; + env->elr_el[2] = env->regs[15]; + } else { + /* + * this is a lie, as there was no c1_sys on V4T/V5, but who cares + * and we should just guard the thumb mode on V4 + */ + if (arm_feature(env, ARM_FEATURE_V4T)) { + env->thumb = + (A32_BANKED_CURRENT_REG_GET(env, sctlr) & SCTLR_TE) != 0; + } + env->regs[14] = env->regs[15] + offset; + } + env->regs[15] = newpc; +} + +static void arm_cpu_do_interrupt_aarch32_hyp(CPUState *cs) +{ + /* + * Handle exception entry to Hyp mode; this is sufficiently + * different to entry to other AArch32 modes that we handle it + * separately here. + * + * The vector table entry used is always the 0x14 Hyp mode entry point, + * unless this is an UNDEF/HVC/abort taken from Hyp to Hyp. + * The offset applied to the preferred return address is always zero + * (see DDI0487C.a section G1.12.3). + * PSTATE A/I/F masks are set based only on the SCR.EA/IRQ/FIQ values. + */ + uint32_t addr, mask; + ARMCPU *cpu = ARM_CPU(cs); + CPUARMState *env = &cpu->env; + + switch (cs->exception_index) { + case EXCP_UDEF: + addr = 0x04; + break; + case EXCP_SWI: + addr = 0x14; + break; + case EXCP_BKPT: + /* Fall through to prefetch abort. */ + case EXCP_PREFETCH_ABORT: + env->cp15.ifar_s = env->exception.vaddress; + qemu_log_mask(CPU_LOG_INT, "...with HIFAR 0x%x\n", + (uint32_t)env->exception.vaddress); + addr = 0x0c; + break; + case EXCP_DATA_ABORT: + env->cp15.dfar_s = env->exception.vaddress; + qemu_log_mask(CPU_LOG_INT, "...with HDFAR 0x%x\n", + (uint32_t)env->exception.vaddress); + addr = 0x10; + break; + case EXCP_IRQ: + addr = 0x18; + break; + case EXCP_FIQ: + addr = 0x1c; + break; + case EXCP_HVC: + addr = 0x08; + break; + case EXCP_HYP_TRAP: + addr = 0x14; + default: + cpu_abort(cs, "Unhandled exception 0x%x\n", cs->exception_index); + } + + if (cs->exception_index != EXCP_IRQ && cs->exception_index != EXCP_FIQ) { + env->cp15.esr_el[2] = env->exception.syndrome; + } + + if (arm_current_el(env) != 2 && addr < 0x14) { + addr = 0x14; + } + + mask = 0; + if (!(env->cp15.scr_el3 & SCR_EA)) { + mask |= CPSR_A; + } + if (!(env->cp15.scr_el3 & SCR_IRQ)) { + mask |= CPSR_I; + } + if (!(env->cp15.scr_el3 & SCR_IRQ)) { + mask |= CPSR_F; + } + + addr += env->cp15.hvbar; + + take_aarch32_exception(env, ARM_CPU_MODE_HYP, mask, 0, addr); +} + static void arm_cpu_do_interrupt_aarch32(CPUState *cs) { ARMCPU *cpu = ARM_CPU(cs); @@ -8048,6 +8165,11 @@ static void arm_cpu_do_interrupt_aarch32(CPUState *cs) env->cp15.mdscr_el1 = deposit64(env->cp15.mdscr_el1, 2, 4, moe); } + if (env->exception.target_el == 2) { + arm_cpu_do_interrupt_aarch32_hyp(cs); + return; + } + /* TODO: Vectored interrupt controller. */ switch (cs->exception_index) { case EXCP_UDEF: @@ -8155,29 +8277,7 @@ static void arm_cpu_do_interrupt_aarch32(CPUState *cs) env->cp15.scr_el3 &= ~SCR_NS; } - switch_mode (env, new_mode); - /* For exceptions taken to AArch32 we must clear the SS bit in both - * PSTATE and in the old-state value we save to SPSR_<mode>, so zero it now. - */ - env->uncached_cpsr &= ~PSTATE_SS; - env->spsr = cpsr_read(env); - /* Clear IT bits. */ - env->condexec_bits = 0; - /* Switch to the new mode, and to the correct instruction set. */ - env->uncached_cpsr = (env->uncached_cpsr & ~CPSR_M) | new_mode; - /* Set new mode endianness */ - env->uncached_cpsr &= ~CPSR_E; - if (env->cp15.sctlr_el[arm_current_el(env)] & SCTLR_EE) { - env->uncached_cpsr |= CPSR_E; - } - env->daif |= mask; - /* this is a lie, as the was no c1_sys on V4T/V5, but who cares - * and we should just guard the thumb mode on V4 */ - if (arm_feature(env, ARM_FEATURE_V4T)) { - env->thumb = (A32_BANKED_CURRENT_REG_GET(env, sctlr) & SCTLR_TE) != 0; - } - env->regs[14] = env->regs[15] + offset; - env->regs[15] = addr; + take_aarch32_exception(env, new_mode, mask, offset, addr); } /* Handle exception entry to a target EL which is using AArch64 */ -- 2.18.0