diff options
Diffstat (limited to 'target/arm/helper.c')
| -rw-r--r-- | target/arm/helper.c | 160 |
1 files changed, 99 insertions, 61 deletions
diff --git a/target/arm/helper.c b/target/arm/helper.c index 7111c8cf18..c23df1b133 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -5947,14 +5947,19 @@ static uint32_t v7m_pop(CPUARMState *env) } /* Switch to V7M main or process stack pointer. */ -static void switch_v7m_sp(CPUARMState *env, int process) +static void switch_v7m_sp(CPUARMState *env, bool new_spsel) { uint32_t tmp; - if (env->v7m.current_sp != process) { + bool old_spsel = env->v7m.control & R_V7M_CONTROL_SPSEL_MASK; + + if (old_spsel != new_spsel) { tmp = env->v7m.other_sp; env->v7m.other_sp = env->regs[13]; env->regs[13] = tmp; - env->v7m.current_sp = process; + + env->v7m.control = deposit32(env->v7m.control, + R_V7M_CONTROL_SPSEL_SHIFT, + R_V7M_CONTROL_SPSEL_LENGTH, new_spsel); } } @@ -5964,8 +5969,13 @@ static void do_v7m_exception_exit(CPUARMState *env) uint32_t xpsr; type = env->regs[15]; - if (env->v7m.exception != 0) + if (env->v7m.exception != ARMV7M_EXCP_NMI) { + /* Auto-clear FAULTMASK on return from other than NMI */ + env->daif &= ~PSTATE_F; + } + if (env->v7m.exception != 0) { armv7m_nvic_complete_irq(env->nvic, env->v7m.exception); + } /* Switch to the target stack. */ switch_v7m_sp(env, (type & 4) != 0); @@ -6014,6 +6024,30 @@ static void arm_log_exception(int idx) } } +static uint32_t arm_v7m_load_vector(ARMCPU *cpu) + +{ + CPUState *cs = CPU(cpu); + CPUARMState *env = &cpu->env; + MemTxResult result; + hwaddr vec = env->v7m.vecbase + env->v7m.exception * 4; + uint32_t addr; + + addr = address_space_ldl(cs->as, vec, + MEMTXATTRS_UNSPECIFIED, &result); + if (result != MEMTX_OK) { + /* Architecturally this should cause a HardFault setting HSFR.VECTTBL, + * which would then be immediately followed by our failing to load + * the entry vector for that HardFault, which is a Lockup case. + * Since we don't model Lockup, we just report this guest error + * via cpu_abort(). + */ + cpu_abort(cs, "Failed to read from exception vector table " + "entry %08x\n", (unsigned)vec); + } + return addr; +} + void arm_v7m_cpu_do_interrupt(CPUState *cs) { ARMCPU *cpu = ARM_CPU(cs); @@ -6025,8 +6059,9 @@ void arm_v7m_cpu_do_interrupt(CPUState *cs) arm_log_exception(cs->exception_index); lr = 0xfffffff1; - if (env->v7m.current_sp) + if (env->v7m.control & R_V7M_CONTROL_SPSEL_MASK) { lr |= 4; + } if (env->v7m.exception == 0) lr |= 8; @@ -6037,6 +6072,11 @@ void arm_v7m_cpu_do_interrupt(CPUState *cs) switch (cs->exception_index) { case EXCP_UDEF: armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_USAGE); + env->v7m.cfsr |= R_V7M_CFSR_UNDEFINSTR_MASK; + return; + case EXCP_NOCP: + armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_USAGE); + env->v7m.cfsr |= R_V7M_CFSR_NOCP_MASK; return; case EXCP_SWI: /* The PC already points to the next instruction. */ @@ -6075,10 +6115,8 @@ void arm_v7m_cpu_do_interrupt(CPUState *cs) return; /* Never happens. Keep compiler happy. */ } - /* Align stack pointer. */ - /* ??? Should only do this if Configuration Control Register - STACKALIGN bit is set. */ - if (env->regs[13] & 4) { + /* Align stack pointer if the guest wants that */ + if ((env->regs[13] & 4) && (env->v7m.ccr & R_V7M_CCR_STKALIGN_MASK)) { env->regs[13] -= 4; xpsr |= 0x200; } @@ -6095,7 +6133,7 @@ void arm_v7m_cpu_do_interrupt(CPUState *cs) /* Clear IT bits */ env->condexec_bits = 0; env->regs[14] = lr; - addr = ldl_phys(cs->as, env->v7m.vecbase + env->v7m.exception * 4); + addr = arm_v7m_load_vector(cpu); env->regs[15] = addr & 0xfffffffe; env->thumb = addr & 1; } @@ -6660,7 +6698,7 @@ void arm_cpu_do_interrupt(CPUState *cs) CPUARMState *env = &cpu->env; unsigned int new_el = env->exception.target_el; - assert(!IS_M(env)); + assert(!arm_feature(env, ARM_FEATURE_M)); arm_log_exception(cs->exception_index); qemu_log_mask(CPU_LOG_INT, "...from EL%d to EL%d\n", arm_current_el(env), @@ -8243,27 +8281,38 @@ hwaddr arm_cpu_get_phys_page_attrs_debug(CPUState *cs, vaddr addr, uint32_t HELPER(v7m_mrs)(CPUARMState *env, uint32_t reg) { - ARMCPU *cpu = arm_env_get_cpu(env); + uint32_t mask; + unsigned el = arm_current_el(env); + + /* First handle registers which unprivileged can read */ + + switch (reg) { + case 0 ... 7: /* xPSR sub-fields */ + mask = 0; + if ((reg & 1) && el) { + mask |= 0x000001ff; /* IPSR (unpriv. reads as zero) */ + } + if (!(reg & 4)) { + mask |= 0xf8000000; /* APSR */ + } + /* EPSR reads as zero */ + return xpsr_read(env) & mask; + break; + case 20: /* CONTROL */ + return env->v7m.control; + } + + if (el == 0) { + return 0; /* unprivileged reads others as zero */ + } switch (reg) { - case 0: /* APSR */ - return xpsr_read(env) & 0xf8000000; - case 1: /* IAPSR */ - return xpsr_read(env) & 0xf80001ff; - case 2: /* EAPSR */ - return xpsr_read(env) & 0xff00fc00; - case 3: /* xPSR */ - return xpsr_read(env) & 0xff00fdff; - case 5: /* IPSR */ - return xpsr_read(env) & 0x000001ff; - case 6: /* EPSR */ - return xpsr_read(env) & 0x0700fc00; - case 7: /* IEPSR */ - return xpsr_read(env) & 0x0700edff; case 8: /* MSP */ - return env->v7m.current_sp ? env->v7m.other_sp : env->regs[13]; + return (env->v7m.control & R_V7M_CONTROL_SPSEL_MASK) ? + env->v7m.other_sp : env->regs[13]; case 9: /* PSP */ - return env->v7m.current_sp ? env->regs[13] : env->v7m.other_sp; + return (env->v7m.control & R_V7M_CONTROL_SPSEL_MASK) ? + env->regs[13] : env->v7m.other_sp; case 16: /* PRIMASK */ return (env->daif & PSTATE_I) != 0; case 17: /* BASEPRI */ @@ -8271,52 +8320,40 @@ uint32_t HELPER(v7m_mrs)(CPUARMState *env, uint32_t reg) return env->v7m.basepri; case 19: /* FAULTMASK */ return (env->daif & PSTATE_F) != 0; - case 20: /* CONTROL */ - return env->v7m.control; default: - /* ??? For debugging only. */ - cpu_abort(CPU(cpu), "Unimplemented system register read (%d)\n", reg); + qemu_log_mask(LOG_GUEST_ERROR, "Attempt to read unknown special" + " register %d\n", reg); return 0; } } void HELPER(v7m_msr)(CPUARMState *env, uint32_t reg, uint32_t val) { - ARMCPU *cpu = arm_env_get_cpu(env); + if (arm_current_el(env) == 0 && reg > 7) { + /* only xPSR sub-fields may be written by unprivileged */ + return; + } switch (reg) { - case 0: /* APSR */ - xpsr_write(env, val, 0xf8000000); - break; - case 1: /* IAPSR */ - xpsr_write(env, val, 0xf8000000); - break; - case 2: /* EAPSR */ - xpsr_write(env, val, 0xfe00fc00); - break; - case 3: /* xPSR */ - xpsr_write(env, val, 0xfe00fc00); - break; - case 5: /* IPSR */ - /* IPSR bits are readonly. */ - break; - case 6: /* EPSR */ - xpsr_write(env, val, 0x0600fc00); - break; - case 7: /* IEPSR */ - xpsr_write(env, val, 0x0600fc00); + case 0 ... 7: /* xPSR sub-fields */ + /* only APSR is actually writable */ + if (reg & 4) { + xpsr_write(env, val, 0xf8000000); /* APSR */ + } break; case 8: /* MSP */ - if (env->v7m.current_sp) + if (env->v7m.control & R_V7M_CONTROL_SPSEL_MASK) { env->v7m.other_sp = val; - else + } else { env->regs[13] = val; + } break; case 9: /* PSP */ - if (env->v7m.current_sp) + if (env->v7m.control & R_V7M_CONTROL_SPSEL_MASK) { env->regs[13] = val; - else + } else { env->v7m.other_sp = val; + } break; case 16: /* PRIMASK */ if (val & 1) { @@ -8341,12 +8378,13 @@ void HELPER(v7m_msr)(CPUARMState *env, uint32_t reg, uint32_t val) } break; case 20: /* CONTROL */ - env->v7m.control = val & 3; - switch_v7m_sp(env, (val & 2) != 0); + switch_v7m_sp(env, (val & R_V7M_CONTROL_SPSEL_MASK) != 0); + env->v7m.control = val & (R_V7M_CONTROL_SPSEL_MASK | + R_V7M_CONTROL_NPRIV_MASK); break; default: - /* ??? For debugging only. */ - cpu_abort(CPU(cpu), "Unimplemented system register write (%d)\n", reg); + qemu_log_mask(LOG_GUEST_ERROR, "Attempt to write unknown special" + " register %d\n", reg); return; } } |