diff options
Diffstat (limited to 'target/nios2/helper.c')
| -rw-r--r-- | target/nios2/helper.c | 363 |
1 files changed, 210 insertions, 153 deletions
diff --git a/target/nios2/helper.c b/target/nios2/helper.c index e5c98650e1..bb3b09e5a7 100644 --- a/target/nios2/helper.c +++ b/target/nios2/helper.c @@ -28,176 +28,234 @@ #include "exec/helper-proto.h" #include "semihosting/semihost.h" -#if defined(CONFIG_USER_ONLY) -void nios2_cpu_do_interrupt(CPUState *cs) +static void do_exception(Nios2CPU *cpu, uint32_t exception_addr, + uint32_t tlbmisc_set, bool is_break) { - Nios2CPU *cpu = NIOS2_CPU(cs); CPUNios2State *env = &cpu->env; - cs->exception_index = -1; - env->regs[R_EA] = env->regs[R_PC] + 4; -} + CPUState *cs = CPU(cpu); + uint32_t old_status = env->ctrl[CR_STATUS]; + uint32_t new_status = old_status; -void nios2_cpu_record_sigsegv(CPUState *cs, vaddr addr, - MMUAccessType access_type, - bool maperr, uintptr_t retaddr) -{ - /* FIXME: Disentangle kuser page from linux-user sigsegv handling. */ - cs->exception_index = 0xaa; - cpu_loop_exit_restore(cs, retaddr); -} + /* With shadow regs, exceptions are always taken into CRS 0. */ + new_status &= ~R_CR_STATUS_CRS_MASK; + env->regs = env->shadow_regs[0]; -#else /* !CONFIG_USER_ONLY */ + if ((old_status & CR_STATUS_EH) == 0) { + int r_ea = R_EA, cr_es = CR_ESTATUS; -void nios2_cpu_do_interrupt(CPUState *cs) -{ - Nios2CPU *cpu = NIOS2_CPU(cs); - CPUNios2State *env = &cpu->env; + if (is_break) { + r_ea = R_BA; + cr_es = CR_BSTATUS; + } + env->ctrl[cr_es] = old_status; + env->regs[r_ea] = env->pc; + + if (cpu->mmu_present) { + new_status |= CR_STATUS_EH; + + /* + * There are 4 bits that are always written. + * Explicitly clear them, to be set via the argument. + */ + env->ctrl[CR_TLBMISC] &= ~(CR_TLBMISC_D | + CR_TLBMISC_PERM | + CR_TLBMISC_BAD | + CR_TLBMISC_DBL); + env->ctrl[CR_TLBMISC] |= tlbmisc_set; + } - switch (cs->exception_index) { - case EXCP_IRQ: - assert(env->regs[CR_STATUS] & CR_STATUS_PIE); + /* + * With shadow regs, and EH == 0, PRS is set from CRS. + * At least, so says Table 3-9, and some other text, + * though Table 3-38 says otherwise. + */ + new_status = FIELD_DP32(new_status, CR_STATUS, PRS, + FIELD_EX32(old_status, CR_STATUS, CRS)); + } - qemu_log_mask(CPU_LOG_INT, "interrupt at pc=%x\n", env->regs[R_PC]); + new_status &= ~(CR_STATUS_PIE | CR_STATUS_U); - env->regs[CR_ESTATUS] = env->regs[CR_STATUS]; - env->regs[CR_STATUS] |= CR_STATUS_IH; - env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U); + env->ctrl[CR_STATUS] = new_status; + if (!is_break) { + env->ctrl[CR_EXCEPTION] = FIELD_DP32(0, CR_EXCEPTION, CAUSE, + cs->exception_index); + } + env->pc = exception_addr; +} - env->regs[CR_EXCEPTION] &= ~(0x1F << 2); - env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2; +static void do_iic_irq(Nios2CPU *cpu) +{ + do_exception(cpu, cpu->exception_addr, 0, false); +} - env->regs[R_EA] = env->regs[R_PC] + 4; - env->regs[R_PC] = cpu->exception_addr; - break; +static void do_eic_irq(Nios2CPU *cpu) +{ + CPUNios2State *env = &cpu->env; + uint32_t old_status = env->ctrl[CR_STATUS]; + uint32_t new_status = old_status; + uint32_t old_rs = FIELD_EX32(old_status, CR_STATUS, CRS); + uint32_t new_rs = cpu->rrs; + + new_status = FIELD_DP32(new_status, CR_STATUS, CRS, new_rs); + new_status = FIELD_DP32(new_status, CR_STATUS, IL, cpu->ril); + new_status = FIELD_DP32(new_status, CR_STATUS, NMI, cpu->rnmi); + new_status &= ~(CR_STATUS_RSIE | CR_STATUS_U); + new_status |= CR_STATUS_IH; + + if (!(new_status & CR_STATUS_EH)) { + new_status = FIELD_DP32(new_status, CR_STATUS, PRS, old_rs); + if (new_rs == 0) { + env->ctrl[CR_ESTATUS] = old_status; + } else { + if (new_rs != old_rs) { + old_status |= CR_STATUS_SRS; + } + env->shadow_regs[new_rs][R_SSTATUS] = old_status; + } + env->shadow_regs[new_rs][R_EA] = env->pc; + } - case EXCP_TLBD: - if ((env->regs[CR_STATUS] & CR_STATUS_EH) == 0) { - qemu_log_mask(CPU_LOG_INT, "TLB MISS (fast) at pc=%x\n", - env->regs[R_PC]); + env->ctrl[CR_STATUS] = new_status; + nios2_update_crs(env); - /* Fast TLB miss */ - /* Variation from the spec. Table 3-35 of the cpu reference shows - * estatus not being changed for TLB miss but this appears to - * be incorrect. */ - env->regs[CR_ESTATUS] = env->regs[CR_STATUS]; - env->regs[CR_STATUS] |= CR_STATUS_EH; - env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U); + env->pc = cpu->rha; +} - env->regs[CR_EXCEPTION] &= ~(0x1F << 2); - env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2; +void nios2_cpu_do_interrupt(CPUState *cs) +{ + Nios2CPU *cpu = NIOS2_CPU(cs); + CPUNios2State *env = &cpu->env; + uint32_t tlbmisc_set = 0; - env->regs[CR_TLBMISC] &= ~CR_TLBMISC_DBL; - env->regs[CR_TLBMISC] |= CR_TLBMISC_WR; + if (qemu_loglevel_mask(CPU_LOG_INT)) { + const char *name = NULL; - env->regs[R_EA] = env->regs[R_PC] + 4; - env->regs[R_PC] = cpu->fast_tlb_miss_addr; + switch (cs->exception_index) { + case EXCP_IRQ: + name = "interrupt"; + break; + case EXCP_TLB_X: + case EXCP_TLB_D: + if (env->ctrl[CR_STATUS] & CR_STATUS_EH) { + name = "TLB MISS (double)"; + } else { + name = "TLB MISS (fast)"; + } + break; + case EXCP_PERM_R: + case EXCP_PERM_W: + case EXCP_PERM_X: + name = "TLB PERM"; + break; + case EXCP_SUPERA_X: + case EXCP_SUPERA_D: + name = "SUPERVISOR (address)"; + break; + case EXCP_SUPERI: + name = "SUPERVISOR (insn)"; + break; + case EXCP_ILLEGAL: + name = "ILLEGAL insn"; + break; + case EXCP_UNALIGN: + name = "Misaligned (data)"; + break; + case EXCP_UNALIGND: + name = "Misaligned (destination)"; + break; + case EXCP_DIV: + name = "DIV error"; + break; + case EXCP_TRAP: + name = "TRAP insn"; + break; + case EXCP_BREAK: + name = "BREAK insn"; + break; + case EXCP_SEMIHOST: + name = "SEMIHOST insn"; + break; + } + if (name) { + qemu_log("%s at pc=0x%08x\n", name, env->pc); } else { - qemu_log_mask(CPU_LOG_INT, "TLB MISS (double) at pc=%x\n", - env->regs[R_PC]); - - /* Double TLB miss */ - env->regs[CR_STATUS] |= CR_STATUS_EH; - env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U); - - env->regs[CR_EXCEPTION] &= ~(0x1F << 2); - env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2; - - env->regs[CR_TLBMISC] |= CR_TLBMISC_DBL; + qemu_log("Unknown exception %d at pc=0x%08x\n", + cs->exception_index, env->pc); + } + } - env->regs[R_PC] = cpu->exception_addr; + switch (cs->exception_index) { + case EXCP_IRQ: + /* Note that PC is advanced for interrupts as well. */ + env->pc += 4; + if (cpu->eic_present) { + do_eic_irq(cpu); + } else { + do_iic_irq(cpu); } break; - case EXCP_TLBR: - case EXCP_TLBW: - case EXCP_TLBX: - qemu_log_mask(CPU_LOG_INT, "TLB PERM at pc=%x\n", env->regs[R_PC]); - - env->regs[CR_ESTATUS] = env->regs[CR_STATUS]; - env->regs[CR_STATUS] |= CR_STATUS_EH; - env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U); - - env->regs[CR_EXCEPTION] &= ~(0x1F << 2); - env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2; - - if ((env->regs[CR_STATUS] & CR_STATUS_EH) == 0) { - env->regs[CR_TLBMISC] |= CR_TLBMISC_WR; + case EXCP_TLB_D: + tlbmisc_set = CR_TLBMISC_D; + /* fall through */ + case EXCP_TLB_X: + if (env->ctrl[CR_STATUS] & CR_STATUS_EH) { + tlbmisc_set |= CR_TLBMISC_DBL; + /* + * Normally, we don't write to tlbmisc unless !EH, + * so do it manually for the double-tlb miss exception. + */ + env->ctrl[CR_TLBMISC] &= ~(CR_TLBMISC_D | + CR_TLBMISC_PERM | + CR_TLBMISC_BAD); + env->ctrl[CR_TLBMISC] |= tlbmisc_set; + do_exception(cpu, cpu->exception_addr, 0, false); + } else { + tlbmisc_set |= CR_TLBMISC_WE; + do_exception(cpu, cpu->fast_tlb_miss_addr, tlbmisc_set, false); } - - env->regs[R_EA] = env->regs[R_PC] + 4; - env->regs[R_PC] = cpu->exception_addr; break; - case EXCP_SUPERA: - case EXCP_SUPERI: - case EXCP_SUPERD: - qemu_log_mask(CPU_LOG_INT, "SUPERVISOR exception at pc=%x\n", - env->regs[R_PC]); - - if ((env->regs[CR_STATUS] & CR_STATUS_EH) == 0) { - env->regs[CR_ESTATUS] = env->regs[CR_STATUS]; - env->regs[R_EA] = env->regs[R_PC] + 4; + case EXCP_PERM_R: + case EXCP_PERM_W: + tlbmisc_set = CR_TLBMISC_D; + /* fall through */ + case EXCP_PERM_X: + tlbmisc_set |= CR_TLBMISC_PERM; + if (!(env->ctrl[CR_STATUS] & CR_STATUS_EH)) { + tlbmisc_set |= CR_TLBMISC_WE; } + do_exception(cpu, cpu->exception_addr, tlbmisc_set, false); + break; - env->regs[CR_STATUS] |= CR_STATUS_EH; - env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U); - - env->regs[CR_EXCEPTION] &= ~(0x1F << 2); - env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2; - - env->regs[R_PC] = cpu->exception_addr; + case EXCP_SUPERA_D: + case EXCP_UNALIGN: + tlbmisc_set = CR_TLBMISC_D; + /* fall through */ + case EXCP_SUPERA_X: + case EXCP_UNALIGND: + tlbmisc_set |= CR_TLBMISC_BAD; + do_exception(cpu, cpu->exception_addr, tlbmisc_set, false); break; + case EXCP_SUPERI: case EXCP_ILLEGAL: + case EXCP_DIV: case EXCP_TRAP: - qemu_log_mask(CPU_LOG_INT, "TRAP exception at pc=%x\n", - env->regs[R_PC]); - - if ((env->regs[CR_STATUS] & CR_STATUS_EH) == 0) { - env->regs[CR_ESTATUS] = env->regs[CR_STATUS]; - env->regs[R_EA] = env->regs[R_PC] + 4; - } - - env->regs[CR_STATUS] |= CR_STATUS_EH; - env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U); - - env->regs[CR_EXCEPTION] &= ~(0x1F << 2); - env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2; - - env->regs[R_PC] = cpu->exception_addr; + do_exception(cpu, cpu->exception_addr, 0, false); break; case EXCP_BREAK: - qemu_log_mask(CPU_LOG_INT, "BREAK exception at pc=%x\n", - env->regs[R_PC]); - /* The semihosting instruction is "break 1". */ - if (semihosting_enabled() && - cpu_ldl_code(env, env->regs[R_PC]) == 0x003da07a) { - qemu_log_mask(CPU_LOG_INT, "Entering semihosting\n"); - env->regs[R_PC] += 4; - do_nios2_semihosting(env); - break; - } - - if ((env->regs[CR_STATUS] & CR_STATUS_EH) == 0) { - env->regs[CR_BSTATUS] = env->regs[CR_STATUS]; - env->regs[R_BA] = env->regs[R_PC] + 4; - } - - env->regs[CR_STATUS] |= CR_STATUS_EH; - env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U); - - env->regs[CR_EXCEPTION] &= ~(0x1F << 2); - env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2; + do_exception(cpu, cpu->exception_addr, 0, true); + break; - env->regs[R_PC] = cpu->exception_addr; + case EXCP_SEMIHOST: + do_nios2_semihosting(env); break; default: - cpu_abort(cs, "unhandled exception type=%d\n", - cs->exception_index); - break; + cpu_abort(cs, "unhandled exception type=%d\n", cs->exception_index); } } @@ -232,9 +290,9 @@ void nios2_cpu_do_unaligned_access(CPUState *cs, vaddr addr, Nios2CPU *cpu = NIOS2_CPU(cs); CPUNios2State *env = &cpu->env; - env->regs[CR_BADADDR] = addr; - env->regs[CR_EXCEPTION] = EXCP_UNALIGN << 2; - helper_raise_exception(env, EXCP_UNALIGN); + env->ctrl[CR_BADADDR] = addr; + cs->exception_index = EXCP_UNALIGN; + nios2_cpu_loop_exit_advance(env, retaddr); } bool nios2_cpu_tlb_fill(CPUState *cs, vaddr address, int size, @@ -243,7 +301,7 @@ bool nios2_cpu_tlb_fill(CPUState *cs, vaddr address, int size, { Nios2CPU *cpu = NIOS2_CPU(cs); CPUNios2State *env = &cpu->env; - unsigned int excp = EXCP_TLBD; + unsigned int excp; target_ulong vaddr, paddr; Nios2MMULookup lu; unsigned int hit; @@ -270,9 +328,10 @@ bool nios2_cpu_tlb_fill(CPUState *cs, vaddr address, int size, if (probe) { return false; } - cs->exception_index = EXCP_SUPERA; - env->regs[CR_BADADDR] = address; - cpu_loop_exit_restore(cs, retaddr); + cs->exception_index = (access_type == MMU_INST_FETCH + ? EXCP_SUPERA_X : EXCP_SUPERA_D); + env->ctrl[CR_BADADDR] = address; + nios2_cpu_loop_exit_advance(env, retaddr); } } @@ -291,25 +350,23 @@ bool nios2_cpu_tlb_fill(CPUState *cs, vaddr address, int size, } /* Permission violation */ - excp = (access_type == MMU_DATA_LOAD ? EXCP_TLBR : - access_type == MMU_DATA_STORE ? EXCP_TLBW : EXCP_TLBX); + excp = (access_type == MMU_DATA_LOAD ? EXCP_PERM_R : + access_type == MMU_DATA_STORE ? EXCP_PERM_W : EXCP_PERM_X); + } else { + excp = (access_type == MMU_INST_FETCH ? EXCP_TLB_X: EXCP_TLB_D); } if (probe) { return false; } - if (access_type == MMU_INST_FETCH) { - env->regs[CR_TLBMISC] &= ~CR_TLBMISC_D; - } else { - env->regs[CR_TLBMISC] |= CR_TLBMISC_D; - } - env->regs[CR_PTEADDR] &= CR_PTEADDR_PTBASE_MASK; - env->regs[CR_PTEADDR] |= (address >> 10) & CR_PTEADDR_VPN_MASK; - env->mmu.pteaddr_wr = env->regs[CR_PTEADDR]; + env->ctrl[CR_TLBMISC] = FIELD_DP32(env->ctrl[CR_TLBMISC], CR_TLBMISC, D, + access_type != MMU_INST_FETCH); + env->ctrl[CR_PTEADDR] = FIELD_DP32(env->ctrl[CR_PTEADDR], CR_PTEADDR, VPN, + address >> TARGET_PAGE_BITS); + env->mmu.pteaddr_wr = env->ctrl[CR_PTEADDR]; cs->exception_index = excp; - env->regs[CR_BADADDR] = address; - cpu_loop_exit_restore(cs, retaddr); + env->ctrl[CR_BADADDR] = address; + nios2_cpu_loop_exit_advance(env, retaddr); } -#endif /* !CONFIG_USER_ONLY */ |