/* * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (C) 1994 - 1999, 2000, 01, 06 Ralf Baechle * Copyright (C) 1995, 1996 Paul M. Antoine * Copyright (C) 1998 Ulf Carlsson * Copyright (C) 1999 Silicon Graphics, Inc. * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com * Copyright (C) 2000, 01 MIPS Technologies, Inc. * Copyright (C) 2002, 2003, 2004, 2005, 2007 Maciej W. Rozycki */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include extern void check_wait(void); extern asmlinkage void r4k_wait(void); extern asmlinkage void rollback_handle_int(void); extern asmlinkage void handle_int(void); extern asmlinkage void handle_tlbm(void); extern asmlinkage void handle_tlbl(void); extern asmlinkage void handle_tlbs(void); extern asmlinkage void handle_adel(void); extern asmlinkage void handle_ades(void); extern asmlinkage void handle_ibe(void); extern asmlinkage void handle_dbe(void); extern asmlinkage void handle_sys(void); extern asmlinkage void handle_bp(void); extern asmlinkage void handle_ri(void); extern asmlinkage void handle_ri_rdhwr_vivt(void); extern asmlinkage void handle_ri_rdhwr(void); extern asmlinkage void handle_cpu(void); extern asmlinkage void handle_ov(void); extern asmlinkage void handle_tr(void); extern asmlinkage void handle_fpe(void); extern asmlinkage void handle_mdmx(void); extern asmlinkage void handle_watch(void); extern asmlinkage void handle_mt(void); extern asmlinkage void handle_dsp(void); extern asmlinkage void handle_mcheck(void); extern asmlinkage void handle_reserved(void); extern int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx, int has_fpu, void *__user *fault_addr); void (*board_be_init)(void); int (*board_be_handler)(struct pt_regs *regs, int is_fixup); void (*board_nmi_handler_setup)(void); void (*board_ejtag_handler_setup)(void); void (*board_bind_eic_interrupt)(int irq, int regset); void (*board_ebase_setup)(void); void __cpuinitdata(*board_cache_error_setup)(void); static void show_raw_backtrace(unsigned long reg29) { unsigned long *sp = (unsigned long *)(reg29 & ~3); unsigned long addr; printk("Call Trace:"); #ifdef CONFIG_KALLSYMS printk("\n"); #endif while (!kstack_end(sp)) { unsigned long __user *p = (unsigned long __user *)(unsigned long)sp++; if (__get_user(addr, p)) { printk(" (Bad stack address)"); break; } if (__kernel_text_address(addr)) print_ip_sym(addr); } printk("\n"); } #ifdef CONFIG_KALLSYMS int raw_show_trace; static int __init set_raw_show_trace(char *str) { raw_show_trace = 1; return 1; } __setup("raw_show_trace", set_raw_show_trace); #endif static void show_backtrace(struct task_struct *task, const struct pt_regs *regs) { unsigned long sp = regs->regs[29]; unsigned long ra = regs->regs[31]; unsigned long pc = regs->cp0_epc; if (!task) task = current; if (raw_show_trace || !__kernel_text_address(pc)) { show_raw_backtrace(sp); return; } printk("Call Trace:\n"); do { print_ip_sym(pc); pc = unwind_stack(task, &sp, pc, &ra); } while (pc); printk("\n"); } /* * This routine abuses get_user()/put_user() to reference pointers * with at least a bit of error checking ... */ static void show_stacktrace(struct task_struct *task, const struct pt_regs *regs) { const int field = 2 * sizeof(unsigned long); long stackdata; int i; unsigned long __user *sp = (unsigned long __user *)regs->regs[29]; printk("Stack :"); i = 0; while ((unsigned long) sp & (PAGE_SIZE - 1)) { if (i && ((i % (64 / field)) == 0)) printk("\n "); if (i > 39) { printk(" ..."); break; } if (__get_user(stackdata, sp++)) { printk(" (Bad stack address)"); break; } printk(" %0*lx", field, stackdata); i++; } printk("\n"); show_backtrace(task, regs); } void show_stack(struct task_struct *task, unsigned long *sp) { struct pt_regs regs; if (sp) { regs.regs[29] = (unsigned long)sp; regs.regs[31] = 0; regs.cp0_epc = 0; } else { if (task && task != current) { regs.regs[29] = task->thread.reg29; regs.regs[31] = 0; regs.cp0_epc = task->thread.reg31; #ifdef CONFIG_KGDB_KDB } else if (atomic_read(&kgdb_active) != -1 && kdb_current_regs) { memcpy(®s, kdb_current_regs, sizeof(regs)); #endif /* CONFIG_KGDB_KDB */ } else { prepare_frametrace(®s); } } show_stacktrace(task, ®s); } /* * The architecture-independent dump_stack generator */ void dump_stack(void) { struct pt_regs regs; prepare_frametrace(®s); show_backtrace(current, ®s); } EXPORT_SYMBOL(dump_stack); static void show_code(unsigned int __user *pc) { long i; unsigned short __user *pc16 = NULL; printk("\nCode:"); if ((unsigned long)pc & 1) pc16 = (unsigned short __user *)((unsigned long)pc & ~1); for(i = -3 ; i < 6 ; i++) { unsigned int insn; if (pc16 ? __get_user(insn, pc16 + i) : __get_user(insn, pc + i)) { printk(" (Bad address in epc)\n"); break; } printk("%c%0*x%c", (i?' ':'<'), pc16 ? 4 : 8, insn, (i?' ':'>')); } } static void __show_regs(const struct pt_regs *regs) { const int field = 2 * sizeof(unsigned long); unsigned int cause = regs->cp0_cause; int i; printk("Cpu %d\n", smp_processor_id()); /* * Saved main processor registers */ for (i = 0; i < 32; ) { if ((i % 4) == 0) printk("$%2d :", i); if (i == 0) printk(" %0*lx", field, 0UL); else if (i == 26 || i == 27) printk(" %*s", field, ""); else printk(" %0*lx", field, regs->regs[i]); i++; if ((i % 4) == 0) printk("\n"); } #ifdef CONFIG_CPU_HAS_SMARTMIPS printk("Acx : %0*lx\n", field, regs->acx); #endif printk("Hi : %0*lx\n", field, regs->hi); printk("Lo : %0*lx\n", field, regs->lo); /* * Saved cp0 registers */ printk("epc : %0*lx %pS\n", field, regs->cp0_epc, (void *) regs->cp0_epc); printk(" %s\n", print_tainted()); printk("ra : %0*lx %pS\n", field, regs->regs[31], (void *) regs->regs[31]); printk("Status: %08x ", (uint32_t) regs->cp0_status); if (current_cpu_data.isa_level == MIPS_CPU_ISA_I) { if (regs->cp0_status & ST0_KUO) printk("KUo "); if (regs->cp0_status & ST0_IEO) printk("IEo "); if (regs->cp0_status & ST0_KUP) printk("KUp "); if (regs->cp0_status & ST0_IEP) printk("IEp "); if (regs->cp0_status & ST0_KUC) printk("KUc "); if (regs->cp0_status & ST0_IEC) printk("IEc "); } else { if (regs->cp0_status & ST0_KX) printk("KX "); if (regs->cp0_status & ST0_SX) printk("SX "); if (regs->cp0_status & ST0_UX) printk("UX "); switch (regs->cp0_status & ST0_KSU) { case KSU_USER: printk("USER "); break; case KSU_SUPERVISOR: printk("SUPERVISOR "); break; case KSU_KERNEL: printk("KERNEL "); break; default: printk("BAD_MODE "); break; } if (regs->cp0_status & ST0_ERL) printk("ERL "); if (regs->cp0_status & ST0_EXL) printk("EXL "); if (regs->cp0_status & ST0_IE) printk("IE "); } printk("\n"); printk("Cause : %08x\n", cause); cause = (cause & CAUSEF_EXCCODE) >> CAUSEB_EXCCODE; if (1 <= cause && cause <= 5) printk("BadVA : %0*lx\n", field, regs->cp0_badvaddr); printk("PrId : %08x (%s)\n", read_c0_prid(), cpu_name_string()); } /* * FIXME: really the generic show_regs should take a const pointer argument. */ void show_regs(struct pt_regs *regs) { __show_regs((struct pt_regs *)regs); } void show_registers(struct pt_regs *regs) { const int field = 2 * sizeof(unsigned long); __show_regs(regs); print_modules(); printk("Process %s (pid: %d, threadinfo=%p, task=%p, tls=%0*lx)\n", current->comm, current->pid, current_thread_info(), current, field, current_thread_info()->tp_value); if (cpu_has_userlocal) { unsigned long tls; tls = read_c0_userlocal(); if (tls != current_thread_info()->tp_value) printk("*HwTLS: %0*lx\n", field, tls); } show_stacktrace(current, regs); show_code((unsigned int __user *) regs->cp0_epc); printk("\n"); } static int regs_to_trapnr(struct pt_regs *regs) { return (regs->cp0_cause >> 2) & 0x1f; } static DEFINE_RAW_SPINLOCK(die_lock); void __noreturn die(const char *str, struct pt_regs *regs) { static int die_counter; int sig = SIGSEGV; #ifdef CONFIG_MIPS_MT_SMTC unsigned long dvpret; #endif /* CONFIG_MIPS_MT_SMTC */ oops_enter(); if (notify_die(DIE_OOPS, str, regs, 0, regs_to_trapnr(regs), SIGSEGV) == NOTIFY_STOP) sig = 0; console_verbose(); raw_spin_lock_irq(&die_lock); #ifdef CONFIG_MIPS_MT_SMTC dvpret = dvpe(); #endif /* CONFIG_MIPS_MT_SMTC */ bust_spinlocks(1); #ifdef CONFIG_MIPS_MT_SMTC mips_mt_regdump(dvpret); #endif /* CONFIG_MIPS_MT_SMTC */ printk("%s[#%d]:\n", str, ++die_counter); show_registers(regs); add_taint(TAINT_DIE); raw_spin_unlock_irq(&die_lock); oops_exit(); if (in_interrupt()) panic("Fatal exception in interrupt"); if (panic_on_oops) { printk(KERN_EMERG "Fatal exception: panic in 5 seconds"); ssleep(5); panic("Fatal exception"); } if (regs && kexec_should_crash(current)) crash_kexec(regs); do_exit(sig); } extern struct exception_table_entry __start___dbe_table[]; extern struct exception_table_entry __stop___dbe_table[]; __asm__( " .section __dbe_table, \"a\"\n" " .previous \n"); /* Given an address, look for it in the exception tables. */ static const struct exception_table_entry *search_dbe_tables(unsigned long addr) { const struct exception_table_entry *e; e = search_extable(__start___dbe_table, __stop___dbe_table - 1, addr); if (!e) e = search_module_dbetables(addr); return e; } asmlinkage void do_be(struct pt_regs *regs) { const int field = 2 * sizeof(unsigned long); const struct exception_table_entry *fixup = NULL; int data = regs->cp0_cause & 4; int action = MIPS_BE_FATAL; /* XXX For now. Fixme, this searches the wrong table ... */ if (data && !user_mode(regs)) fixup = search_dbe_tables(exception_epc(regs)); if (fixup) action = MIPS_BE_FIXUP; if (board_be_handler) action = board_be_handler(regs, fixup != NULL); switch (action) { case MIPS_BE_DISCARD: return; case MIPS_BE_FIXUP: if (fixup) { regs->cp0_epc = fixup->nextinsn; return; } break; default: break; } /* * Assume it would be too dangerous to continue ... */ printk(KERN_ALERT "%s bus error, epc == %0*lx, ra == %0*lx\n", data ? "Data" : "Instruction", field, regs->cp0_epc, field, regs->regs[31]); if (notify_die(DIE_OOPS, "bus error", regs, 0, regs_to_trapnr(regs), SIGBUS) == NOTIFY_STOP) return; die_if_kernel("Oops", regs); force_sig(SIGBUS, current); } /* * ll/sc, rdhwr, sync emulation */ #define OPCODE 0xfc000000 #define BASE 0x03e00000 #define RT 0x001f0000 #define OFFSET 0x0000ffff #define LL 0xc0000000 #define SC 0xe0000000 #define SPEC0 0x00000000 #define SPEC3 0x7c000000 #define RD 0x0000f800 #define FUNC 0x0000003f #define SYNC 0x0000000f #define RDHWR 0x0000003b /* * The ll_bit is cleared by r*_switch.S */ unsigned int ll_bit; struct task_struct *ll_task; static inline int simulate_ll(struct pt_regs *regs, unsigned int opcode) { unsigned long value, __user *vaddr; long offset; /* * analyse the ll instruction that just caused a ri exception * and put the referenced address to addr. */ /* sign extend offset */ offset = opcode & OFFSET; offset <<= 16; offset >>= 16; vaddr = (unsigned long __user *) ((unsigned long)(regs->regs[(opcode & BASE) >> 21]) + offset); if ((unsigned long)vaddr & 3) return SIGBUS; if (get_user(value, vaddr)) return SIGSEGV; preempt_disable(); if (ll_task == NULL || ll_task == current) { ll_bit = 1; } else { ll_bit = 0; } ll_task = current; preempt_enable(); regs->regs[(opcode & RT) >> 16] = value; return 0; } static inline int simulate_sc(struct pt_regs *regs, unsigned int opcode) { unsigned long __user *vaddr; unsigned long reg; long offset; /* * analyse the sc instruction that just caused a ri exception * and put the referenced address to addr. */ /* sign extend offset */ offset = opcode & OFFSET; offset <<= 16; offset >>= 16; vaddr = (unsigned long __user *) ((unsigned long)(regs->regs[(opcode & BASE) >> 21]) + offset); reg = (opcode & RT) >> 16; if ((unsigned long)vaddr & 3) return SIGBUS; preempt_disable(); if (ll_bit == 0 || ll_task != current) { regs->regs[reg] = 0; preempt_enable(); return 0; } preempt_enable(); if (put_user(regs->regs[reg], vaddr)) return SIGSEGV; regs->regs[reg] = 1; return 0; } /* * ll uses the opcode of lwc0 and sc uses the opcode of swc0. That is both * opcodes are supposed to result in coprocessor unusable exceptions if * executed on ll/sc-less processors. That's the theory. In practice a * few processors such as NEC's VR4100 throw reserved instruction exceptions * instead, so we're doing the emulation thing in both exception handlers. */ static int simulate_llsc(struct pt_regs *regs, unsigned int opcode) { if ((opcode & OPCODE) == LL) { perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0); return simulate_ll(regs, opcode); } if ((opcode & OPCODE) == SC) { perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0); return simulate_sc(regs, opcode); } return -1; /* Must be something else ... */ } /* * Simulate trapping 'rdhwr' instructions to provide user accessible * registers not implemented in hardware. */ static int simulate_rdhwr(struct pt_regs *regs, unsigned int opcode) { struct thread_info *ti = task_thread_info(current); if ((opcode & OPCODE) == SPEC3 && (opcode & FUNC) == RDHWR) { int rd = (opcode & RD) >> 11; int rt = (opcode & RT) >> 16; perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0); switch (rd) { case 0: /* CPU number */ regs->regs[rt] = smp_processor_id(); return 0; case 1: /* SYNCI length */ regs->regs[rt] = min(current_cpu_data.dcache.linesz, current_cpu_data.icache.linesz); return 0; case 2: /* Read count register */ regs->regs[rt] = read_c0_count(); return 0; case 3: /* Count register resolution */ switch (current_cpu_data.cputype) { case CPU_20KC: case CPU_25KF: regs->regs[rt] = 1; break; default: regs->regs[rt] = 2; } return 0; case 29: regs->regs[rt] = ti->tp_value; return 0; default: return -1; } } /* Not ours. */ return -1; } static int simulate_sync(struct pt_regs *regs, unsigned int opcode) { if ((opcode & OPCODE) == SPEC0 && (opcode & FUNC) == SYNC) { perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0); return 0; } return -1; /* Must be something else ... */ } asmlinkage void do_ov(struct pt_regs *regs) { siginfo_t info; die_if_kernel("Integer overflow", regs); info.si_code = FPE_INTOVF; info.si_signo = SIGFPE; info.si_errno = 0; info.si_addr = (void __user *) regs->cp0_epc; force_sig_info(SIGFPE, &info, current); } static int process_fpemu_return(int sig, void __user *fault_addr) { if (sig == SIGSEGV || sig == SIGBUS) { struct siginfo si = {0}; si.si_addr = fault_addr; si.si_signo = sig; if (sig == SIGSEGV) { if (find_vma(current->mm, (unsigned long)fault_addr)) si.si_code = SEGV_ACCERR; else si.si_code = SEGV_MAPERR; } else { si.si_code = BUS_ADRERR; } force_sig_info(sig, &si, current); return 1; } else if (sig) { force_sig(sig, current); return 1; } else { return 0; } } /* * XXX Delayed fp exceptions when doing a lazy ctx switch XXX */ asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31) { siginfo_t info = {0}; if (notify_die(DIE_FP, "FP exception", regs, 0, regs_to_trapnr(regs), SIGFPE) == NOTIFY_STOP) return; die_if_kernel("FP exception in kernel code", regs); if (fcr31 & FPU_CSR_UNI_X) { int sig; void __user *fault_addr = NULL; /* * Unimplemented operation exception. If we've got the full * software emulator on-board, let's use it... * * Force FPU to dump state into task/thread context. We're * moving a lot of data here for what is probably a single * instruction, but the alternative is to pre-decode the FP * register operands before invoking the emulator, which seems * a bit extreme for what should be an infrequent event. */ /* Ensure 'resume' not overwrite saved fp context again. */ lose_fpu(1); /* Run the emulator */ sig = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1, &fault_addr); /* * We can't allow the emulated instruction to leave any of * the cause bit set in $fcr31. */ current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X; /* Restore the hardware register state */ own_fpu(1); /* Using the FPU again. */ /* If something went wrong, signal */ process_fpemu_return(sig, fault_addr); return; } else if (fcr31 & FPU_CSR_INV_X) info.si_code = FPE_FLTINV; else if (fcr31 & FPU_CSR_DIV_X) info.si_code = FPE_FLTDIV; else if (fcr31 & FPU_CSR_OVF_X) info.si_code = FPE_FLTOVF; else if (fcr31 & FPU_CSR_UDF_X) info.si_code = FPE_FLTUND; else if (fcr31 & FPU_CSR_INE_X) info.si_code = FPE_FLTRES; else info.si_code = __SI_FAULT; info.si_signo = SIGFPE; info.si_errno = 0; info.si_addr = (void __user *) regs->cp0_epc; force_sig_info(SIGFPE, &info, current); } static void do_trap_or_bp(struct pt_regs *regs, unsigned int code, const char *str) { siginfo_t info; char b[40]; #ifdef CONFIG_KGDB_LOW_LEVEL_TRAP if (kgdb_ll_trap(DIE_TRAP, str, regs, code, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP) return; #endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */ if (notify_die(DIE_TRAP, str, regs, code, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP) return; /* * A short test says that IRIX 5.3 sends SIGTRAP for all trap * insns, even for trap and break codes that indicate arithmetic * failures. Weird ... * But should we continue the brokenness??? --macro */ switch (code) { case BRK_OVERFLOW: case BRK_DIVZERO: scnprintf(b, sizeof(b), "%s instruction in kernel code", str); die_if_kernel(b, regs); if (code == BRK_DIVZERO) info.si_code = FPE_INTDIV; else info.si_code = FPE_INTOVF; info.si_signo = SIGFPE; info.si_errno = 0; info.si_addr = (void __user *) regs->cp0_epc; force_sig_info(SIGFPE, &info, current); break; case BRK_BUG: die_if_kernel("Kernel bug detected", regs); force_sig(SIGTRAP, current); break; case BRK_MEMU: /* * Address errors may be deliberately induced by the FPU * emulator to retake control of the CPU after executing the * instruction in the delay slot of an emulated branch. * * Terminate if exception was recognized as a delay slot return * otherwise handle as normal. */ if (do_dsemulret(regs)) return; die_if_kernel("Math emu break/trap", regs); force_sig(SIGTRAP, current); break; default: scnprintf(b, sizeof(b), "%s instruction in kernel code", str); die_if_kernel(b, regs); force_sig(SIGTRAP, current); } } asmlinkage void do_bp(struct pt_regs *regs) { unsigned int opcode, bcode; if (__get_user(opcode, (unsigned int __user *) exception_epc(regs))) goto out_sigsegv; /* * There is the ancient bug in the MIPS assemblers that the break * code starts left to bit 16 instead to bit 6 in the opcode. * Gas is bug-compatible, but not always, grrr... * We handle both cases with a simple heuristics. --macro */ bcode = ((opcode >> 6) & ((1 << 20) - 1)); if (bcode >= (1 << 10)) bcode >>= 10; /* * notify the kprobe handlers, if instruction is likely to * pertain to them. */ switch (bcode) { case BRK_KPROBE_BP: if (notify_die(DIE_BREAK, "debug", regs, bcode, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP) return; else break; case BRK_KPROBE_SSTEPBP: if (notify_die(DIE_SSTEPBP, "single_step", regs, bcode, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP) return; else break; default: break; } do_trap_or_bp(regs, bcode, "Break"); return; out_sigsegv: force_sig(SIGSEGV, current); } asmlinkage void do_tr(struct pt_regs *regs) { unsigned int opcode, tcode = 0; if (__get_user(opcode, (unsigned int __user *) exception_epc(regs))) goto out_sigsegv; /* Immediate versions don't provide a code. */ if (!(opcode & OPCODE)) tcode = ((opcode >> 6) & ((1 << 10) - 1)); do_trap_or_bp(regs, tcode, "Trap"); return; out_sigsegv: force_sig(SIGSEGV, current); } asmlinkage void do_ri(struct pt_regs *regs) { unsigned int __user *epc = (unsigned int __user *)exception_epc(regs); unsigned long old_epc = regs->cp0_epc; unsigned int opcode = 0; int status = -1; if (notify_die(DIE_RI, "RI Fault", regs, 0, regs_to_trapnr(regs), SIGILL) == NOTIFY_STOP) return; die_if_kernel("Reserved instruction in kernel code", regs); if (unlikely(compute_return_epc(regs) < 0)) return; if (unlikely(get_user(opcode, epc) < 0)) status = SIGSEGV; if (!cpu_has_llsc && status < 0) status = simulate_llsc(regs, opcode); if (status < 0) status = simulate_rdhwr(regs, opcode); if (status < 0) status = simulate_sync(regs, opcode); if (status < 0) status = SIGILL; if (unlikely(status > 0)) { regs->cp0_epc = old_epc; /* Undo skip-over. */ force_sig(status, current); } } /* * MIPS MT processors may have fewer FPU contexts than CPU threads. If we've * emulated more than some threshold number of instructions, force migration to * a "CPU" that has FP support. */ static void mt_ase_fp_affinity(void) { #ifdef CONFIG_MIPS_MT_FPAFF if (mt_fpemul_threshold > 0 && ((current->thread.emulated_fp++ > mt_fpemul_threshold))) { /* * If there's no FPU present, or if the application has already * restricted the allowed set to exclude any CPUs with FPUs, * we'll skip the procedure. */ if (cpus_intersects(current->cpus_allowed, mt_fpu_cpumask)) { cpumask_t tmask; current->thread.user_cpus_allowed = current->cpus_allowed; cpus_and(tmask, current->cpus_allowed, mt_fpu_cpumask); set_cpus_allowed_ptr(current, &tmask); set_thread_flag(TIF_FPUBOUND); } } #endif /* CONFIG_MIPS_MT_FPAFF */ } /* * No lock; only written during early bootup by CPU 0. */ static RAW_NOTIFIER_HEAD(cu2_chain); int __ref register_cu2_notifier(struct notifier_block *nb) { return raw_notifier_chain_register(&cu2_chain, nb); } int cu2_notifier_call_chain(unsigned long val, void *v) { return raw_notifier_call_chain(&cu2_chain, val, v); } static int default_cu2_call(struct notifier_block *nfb, unsigned long action, void *data) { struct pt_regs *regs = data; switch (action) { default: die_if_kernel("Unhandled kernel unaligned access or invalid " "instruction", regs); /* Fall through */ case CU2_EXCEPTION: force_sig(SIGILL, current); } return NOTIFY_OK; } asmlinkage void do_cpu(struct pt_regs *regs) { unsigned int __user *epc; unsigned long old_epc; unsigned int opcode; unsigned int cpid; int status; unsigned long __maybe_unused flags; die_if_kernel("do_cpu invoked from kernel context!", regs); cpid = (regs->cp0_cause >> CAUSEB_CE) & 3; switch (cpid) { case 0: epc = (unsigned int __user *)exception_epc(regs); old_epc = regs->cp0_epc; opcode = 0; status = -1; if (unlikely(compute_return_epc(regs) < 0)) return; if (unlikely(get_user(opcode, epc) < 0)) status = SIGSEGV; if (!cpu_has_llsc && status < 0) status = simulate_llsc(regs, opcode); if (status < 0) status = simulate_rdhwr(regs, opcode); if (status < 0) status = SIGILL; if (unlikely(status > 0)) { regs->cp0_epc = old_epc; /* Undo skip-over. */ force_sig(status, current); } return; case 1: if (used_math()) /* Using the FPU again. */ own_fpu(1); else { /* First time FPU user. */ init_fpu(); set_used_math(); } if (!raw_cpu_has_fpu) { int sig; void __user *fault_addr = NULL; sig = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 0, &fault_addr); if (!process_fpemu_return(sig, fault_addr)) mt_ase_fp_affinity(); } return; case 2: raw_notifier_call_chain(&cu2_chain, CU2_EXCEPTION, regs); return; case 3: break; } force_sig(SIGILL, current); } asmlinkage void do_mdmx(struct pt_regs *regs) { force_sig(SIGILL, current); } /* * Called with interrupts disabled. */ asmlinkage void do_watch(struct pt_regs *regs) { u32 cause; /* * Clear WP (bit 22) bit of cause register so we don't loop * forever. */ cause = read_c0_cause(); cause &= ~(1 << 22); write_c0_cause(cause); /* * If the current thread has the watch registers loaded, save * their values and send SIGTRAP. Otherwise another thread * left the registers set, clear them and continue. */ if (test_tsk_thread_flag(current, TIF_LOAD_WATCH)) { mips_read_watch_registers(); local_irq_enable(); force_sig(SIGTRAP, current); } else { mips_clear_watch_registers(); local_irq_enable(); } } asmlinkage void do_mcheck(struct pt_regs *regs) { const int field = 2 * sizeof(unsigned long); int multi_match = regs->cp0_status & ST0_TS; show_regs(regs); if (multi_match) { printk("Index : %0x\n", read_c0_index()); printk("Pagemask: %0x\n", read_c0_pagemask()); printk("EntryHi : %0*lx\n", field, read_c0_entryhi()); printk("EntryLo0: %0*lx\n", field, read_c0_entrylo0()); printk("EntryLo1: %0*lx\n", field, read_c0_entrylo1()); printk("\n"); dump_tlb_all(); } show_code((unsigned int __user *) regs->cp0_epc); /* * Some chips may have other causes of machine check (e.g. SB1 * graduation timer) */ panic("Caught Machine Check exception - %scaused by multiple " "matching entries in the TLB.", (multi_match) ? "" : "not "); } asmlinkage void do_mt(struct pt_regs *regs) { int subcode; subcode = (read_vpe_c0_vpecontrol() & VPECONTROL_EXCPT) >> VPECONTROL_EXCPT_SHIFT; switch (subcode) { case 0: printk(KERN_DEBUG "Thread Underflow\n"); break; case 1: printk(KERN_DEBUG "Thread Overflow\n"); break; case 2: printk(KERN_DEBUG "Invalid YIELD Qualifier\n"); break; case 3: printk(KERN_DEBUG "Gating Storage Exception\n"); break; case 4: printk(KERN_DEBUG "YIELD Scheduler Exception\n"); break; case 5: printk(KERN_DEBUG "Gating Storage Scheduler Exception\n"); break; default: printk(KERN_DEBUG "*** UNKNOWN THREAD EXCEPTION %d ***\n", subcode); break; } die_if_kernel("MIPS MT Thread exception in kernel", regs); force_sig(SIGILL, current); } asmlinkage void do_dsp(struct pt_regs *regs) { if (cpu_has_dsp) panic("Unexpected DSP exception"); force_sig(SIGILL, current); } asmlinkage void do_reserved(struct pt_regs *regs) { /* * Game over - no way to handle this if it ever occurs. Most probably * caused by a new unknown cpu type or after another deadly * hard/software error. */ show_regs(regs); panic("Caught reserved exception %ld - should not happen.", (regs->cp0_cause & 0x7f) >> 2); } static int __initdata l1parity = 1; static int __init nol1parity(char *s) { l1parity = 0; return 1; } __setup("nol1par", nol1parity); static int __initdata l2parity = 1; static int __init nol2parity(char *s) { l2parity = 0; return 1; } __setup("nol2par", nol2parity); /* * Some MIPS CPUs can enable/disable for cache parity detection, but do * it different ways. */ static inline void parity_protection_init(void) { switch (current_cpu_type()) { case CPU_24K: case CPU_34K: case CPU_74K: case CPU_1004K: { #define ERRCTL_PE 0x80000000 #define ERRCTL_L2P 0x00800000 unsigned long errctl; unsigned int l1parity_present, l2parity_present; errctl = read_c0_ecc(); errctl &= ~(ERRCTL_PE|ERRCTL_L2P); /* probe L1 parity support */ write_c0_ecc(errctl | ERRCTL_PE); back_to_back_c0_hazard(); l1parity_present = (read_c0_ecc() & ERRCTL_PE); /* probe L2 parity support */ write_c0_ecc(errctl|ERRCTL_L2P); back_to_back_c0_hazard(); l2parity_present = (read_c0_ecc() & ERRCTL_L2P); if (l1parity_present && l2parity_present) { if (l1parity) errctl |= ERRCTL_PE; if (l1parity ^ l2parity) errctl |= ERRCTL_L2P; } else if (l1parity_present) { if (l1parity) errctl |= ERRCTL_PE; } else if (l2parity_present) { if (l2parity) errctl |= ERRCTL_L2P; } else { /* No parity available */ } printk(KERN_INFO "Writing ErrCtl register=%08lx\n", errctl); write_c0_ecc(errctl); back_to_back_c0_hazard(); errctl = read_c0_ecc(); printk(KERN_INFO "Readback ErrCtl register=%08lx\n", errctl); if (l1parity_present) printk(KERN_INFO "Cache parity protection %sabled\n", (errctl & ERRCTL_PE) ? "en" : "dis"); if (l2parity_present) { if (l1parity_present && l1parity) errctl ^= ERRCTL_L2P; printk(KERN_INFO "L2 cache parity protection %sabled\n", (errctl & ERRCTL_L2P) ? "en" : "dis"); } } break; case CPU_5KC: case CPU_5KE: case CPU_LOONGSON1: write_c0_ecc(0x80000000); back_to_back_c0_hazard(); /* Set the PE bit (bit 31) in the c0_errctl register. */ printk(KERN_INFO "Cache parity protection %sabled\n", (read_c0_ecc() & 0x80000000) ? "en" : "dis"); break; case CPU_20KC: case CPU_25KF: /* Clear the DE bit (bit 16) in the c0_status register. */ printk(KERN_INFO "Enable cache parity protection for " "MIPS 20KC/25KF CPUs.\n"); clear_c0_status(ST0_DE); break; default: break; } } asmlinkage void cache_parity_error(void) { const int field = 2 * sizeof(unsigned long); unsigned int reg_val; /* For the moment, report the problem and hang. */ printk("Cache error exception:\n"); printk("cp0_errorepc == %0*lx\n", field, read_c0_errorepc()); reg_val = read_c0_cacheerr(); printk("c0_cacheerr == %08x\n", reg_val); printk("Decoded c0_cacheerr: %s cache fault in %s reference.\n", reg_val & (1<<30) ? "secondary" : "primary", reg_val & (1<<31) ? "data" : "insn"); printk("Error bits: %s%s%s%s%s%s%s\n", reg_val & (1<<29) ? "ED " : "", reg_val & (1<<28) ? "ET " : "", reg_val & (1<<26) ? "EE " : "", reg_val & (1<<25) ? "EB " : "", reg_val & (1<<24) ? "EI " : "", reg_val & (1<<23) ? "E1 " : "", reg_val & (1<<22) ? "E0 " : ""); printk("IDX: 0x%08x\n", reg_val & ((1<<22)-1)); #if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64) if (reg_val & (1<<22)) printk("DErrAddr0: 0x%0*lx\n", field, read_c0_derraddr0()); if (reg_val & (1<<23)) printk("DErrAddr1: 0x%0*lx\n", field, read_c0_derraddr1()); #endif panic("Can't handle the cache error!"); } /* * SDBBP EJTAG debug exception handler. * We skip the instruction and return to the next instruction. */ void ejtag_exception_handler(struct pt_regs *regs) { const int field = 2 * sizeof(unsigned long); unsigned long depc, old_epc; unsigned int debug; printk(KERN_DEBUG "SDBBP EJTAG debug exception - not handled yet, just ignored!\n"); depc = read_c0_depc(); debug = read_c0_debug(); printk(KERN_DEBUG "c0_depc = %0*lx, DEBUG = %08x\n", field, depc, debug); if (debug & 0x80000000) { /* * In branch delay slot. * We cheat a little bit here and use EPC to calculate the * debug return address (DEPC). EPC is restored after the * calculation. */ old_epc = regs->cp0_epc; regs->cp0_epc = depc; __compute_return_epc(regs); depc = regs->cp0_epc; regs->cp0_epc = old_epc; } else depc += 4; write_c0_depc(depc); #if 0 printk(KERN_DEBUG "\n\n----- Enable EJTAG single stepping ----\n\n"); write_c0_debug(debug | 0x100); #endif } /* * NMI exception handler. * No lock; only written during early bootup by CPU 0. */ static RAW_NOTIFIER_HEAD(nmi_chain); int register_nmi_notifier(struct notifier_block *nb) { return raw_notifier_chain_register(&nmi_chain, nb); } void __noreturn nmi_exception_handler(struct pt_regs *regs) { raw_notifier_call_chain(&nmi_chain, 0, regs); bust_spinlocks(1); printk("NMI taken!!!!\n"); die("NMI", regs); } #define VECTORSPACING 0x100 /* for EI/VI mode */ unsigned long ebase; unsigned long exception_handlers[32]; unsigned long vi_handlers[64]; void __init *set_except_vector(int n, void *addr) { unsigned long handler = (unsigned long) addr; unsigned long old_handler = exception_handlers[n]; exception_handlers[n] = handler; if (n == 0 && cpu_has_divec) { unsigned long jump_mask = ~((1 << 28) - 1); u32 *buf = (u32 *)(ebase + 0x200); unsigned int k0 = 26; if ((handler & jump_mask) == ((ebase + 0x200) & jump_mask)) { uasm_i_j(&buf, handler & ~jump_mask); uasm_i_nop(&buf); } else { UASM_i_LA(&buf, k0, handler); uasm_i_jr(&buf, k0); uasm_i_nop(&buf); } local_flush_icache_range(ebase + 0x200, (unsigned long)buf); } return (void *)old_handler; } static asmlinkage void do_default_vi(void) { show_regs(get_irq_regs()); panic("Caught unexpected vectored interrupt."); } static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs) { unsigned long handler; unsigned long old_handler = vi_handlers[n]; int srssets = current_cpu_data.srsets; u32 *w; unsigned char *b; BUG_ON(!cpu_has_veic && !cpu_has_vint); if (addr == NULL) { handler = (unsigned long) do_default_vi; srs = 0; } else handler = (unsigned long) addr; vi_handlers[n] = (unsigned long) addr; b = (unsigned char *)(ebase + 0x200 + n*VECTORSPACING); if (srs >= srssets) panic("Shadow register set %d not supported", srs); if (cpu_has_veic) { if (board_bind_eic_interrupt) board_bind_eic_interrupt(n, srs); } else if (cpu_has_vint) { /* SRSMap is only defined if shadow sets are implemented */ if (srssets > 1) change_c0_srsmap(0xf << n*4, srs << n*4); } if (srs == 0) { /* * If no shadow set is selected then use the default handler * that does normal register saving and a standard interrupt exit */ extern char except_vec_vi, except_vec_vi_lui; extern char except_vec_vi_ori, except_vec_vi_end; extern char rollback_except_vec_vi; char *vec_start = (cpu_wait == r4k_wait) ? &rollback_except_vec_vi : &except_vec_vi; #ifdef CONFIG_MIPS_MT_SMTC /* * We need to provide the SMTC vectored interrupt handler * not only with the address of the handler, but with the * Status.IM bit to be masked before going there. */ extern char except_vec_vi_mori; const int mori_offset = &except_vec_vi_mori - vec_start; #endif /* CONFIG_MIPS_MT_SMTC */ const int handler_len = &except_vec_vi_end - vec_start; const int lui_offset = &except_vec_vi_lui - vec_start; const int ori_offset = &except_vec_vi_ori - vec_start; if (handler_len > VECTORSPACING) { /* * Sigh... panicing won't help as the console * is probably not configured :( */ panic("VECTORSPACING too small"); } memcpy(b, vec_start, handler_len); #ifdef CONFIG_MIPS_MT_SMTC BUG_ON(n > 7); /* Vector index %d exceeds SMTC maximum. */ w = (u32 *)(b + mori_offset); *w = (*w & 0xffff0000) | (0x100 << n); #endif /* CONFIG_MIPS_MT_SMTC */ w = (u32 *)(b + lui_offset); *w = (*w & 0xffff0000) | (((u32)handler >> 16) & 0xffff); w = (u32 *)(b + ori_offset); *w = (*w & 0xffff0000) | ((u32)handler & 0xffff); local_flush_icache_range((unsigned long)b, (unsigned long)(b+handler_len)); } else { /* * In other cases jump directly to the interrupt handler * * It is the handlers responsibility to save registers if required * (eg hi/lo) and return from the exception using "eret" */ w = (u32 *)b; *w++ = 0x08000000 | (((u32)handler >> 2) & 0x03fffff); /* j handler */ *w = 0; local_flush_icache_range((unsigned long)b, (unsigned long)(b+8)); } return (void *)old_handler; } void *set_vi_handler(int n, vi_handler_t addr) { return set_vi_srs_handler(n, addr, 0); } extern void tlb_init(void); extern void flush_tlb_handlers(void); /* * Timer interrupt */ int cp0_compare_irq; EXPORT_SYMBOL_GPL(cp0_compare_irq); int cp0_compare_irq_shift; /* * Performance counter IRQ or -1 if shared with timer */ int cp0_perfcount_irq; EXPORT_SYMBOL_GPL(cp0_perfcount_irq); static int __cpuinitdata noulri; static int __init ulri_disable(char *s) { pr_info("Disabling ulri\n"); noulri = 1; return 1; } __setup("noulri", ulri_disable); void __cpuinit per_cpu_trap_init(bool is_boot_cpu) { unsigned int cpu = smp_processor_id(); unsigned int status_set = ST0_CU0; unsigned int hwrena = cpu_hwrena_impl_bits; #ifdef CONFIG_MIPS_MT_SMTC int secondaryTC = 0; int bootTC = (cpu == 0); /* * Only do per_cpu_trap_init() for first TC of Each VPE. * Note that this hack assumes that the SMTC init code * assigns TCs consecutively and in ascending order. */ if (((read_c0_tcbind() & TCBIND_CURTC) != 0) && ((read_c0_tcbind() & TCBIND_CURVPE) == cpu_data[cpu - 1].vpe_id)) secondaryTC = 1; #endif /* CONFIG_MIPS_MT_SMTC */ /* * Disable coprocessors and select 32-bit or 64-bit addressing * and the 16/32 or 32/32 FPR register model. Reset the BEV * flag that some firmware may have left set and the TS bit (for * IP27). Set XX for ISA IV code to work. */ #ifdef CONFIG_64BIT status_set |= ST0_FR|ST0_KX|ST0_SX|ST0_UX; #endif if (current_cpu_data.isa_level == MIPS_CPU_ISA_IV) status_set |= ST0_XX; if (cpu_has_dsp) status_set |= ST0_MX; change_c0_status(ST0_CU|ST0_MX|ST0_RE|ST0_FR|ST0_BEV|ST0_TS|ST0_KX|ST0_SX|ST0_UX, status_set); if (cpu_has_mips_r2) hwrena |= 0x0000000f; if (!noulri && cpu_has_userlocal) hwrena |= (1 << 29); if (hwrena) write_c0_hwrena(hwrena); #ifdef CONFIG_MIPS_MT_SMTC if (!secondaryTC) { #endif /* CONFIG_MIPS_MT_SMTC */ if (cpu_has_veic || cpu_has_vint) { unsigned long sr = set_c0_status(ST0_BEV); write_c0_ebase(ebase); write_c0_status(sr); /* Setting vector spacing enables EI/VI mode */ change_c0_intctl(0x3e0, VECTORSPACING); } if (cpu_has_divec) { if (cpu_has_mipsmt) { unsigned int vpflags = dvpe(); set_c0_cause(CAUSEF_IV); evpe(vpflags); } else set_c0_cause(CAUSEF_IV); } /* * Before R2 both interrupt numbers were fixed to 7, so on R2 only: * * o read IntCtl.IPTI to determine the timer interrupt * o read IntCtl.IPPCI to determine the performance counter interrupt */ if (cpu_has_mips_r2) { cp0_compare_irq_shift = CAUSEB_TI - CAUSEB_IP; cp0_compare_irq = (read_c0_intctl() >> INTCTLB_IPTI) & 7; cp0_perfcount_irq = (read_c0_intctl() >> INTCTLB_IPPCI) & 7; if (cp0_perfcount_irq == cp0_compare_irq) cp0_perfcount_irq = -1; } else { cp0_compare_irq = CP0_LEGACY_COMPARE_IRQ; cp0_compare_irq_shift = CP0_LEGACY_PERFCNT_IRQ; cp0_perfcount_irq = -1; } #ifdef CONFIG_MIPS_MT_SMTC } #endif /* CONFIG_MIPS_MT_SMTC */ if (!cpu_data[cpu].asid_cache) cpu_data[cpu].asid_cache = ASID_FIRST_VERSION; atomic_inc(&init_mm.mm_count); current->active_mm = &init_mm; BUG_ON(current->mm); enter_lazy_tlb(&init_mm, current); #ifdef CONFIG_MIPS_MT_SMTC if (bootTC) { #endif /* CONFIG_MIPS_MT_SMTC */ /* Boot CPU's cache setup in setup_arch(). */ if (!is_boot_cpu) cpu_cache_init(); tlb_init(); #ifdef CONFIG_MIPS_MT_SMTC } else if (!secondaryTC) { /* * First TC in non-boot VPE must do subset of tlb_init() * for MMU countrol registers. */ write_c0_pagemask(PM_DEFAULT_MASK); write_c0_wired(0); } #endif /* CONFIG_MIPS_MT_SMTC */ TLBMISS_HANDLER_SETUP(); } /* Install CPU exception handler */ void __cpuinit set_handler(unsigned long offset, void *addr, unsigned long size) { memcpy((void *)(ebase + offset), addr, size); local_flush_icache_range(ebase + offset, ebase + offset + size); } static char panic_null_cerr[] __cpuinitdata = "Trying to set NULL cache error exception handler"; /* * Install uncached CPU exception handler. * This is suitable only for the cache error exception which is the only * exception handler that is being run uncached. */ void __cpuinit set_uncached_handler(unsigned long offset, void *addr, unsigned long size) { unsigned long uncached_ebase = CKSEG1ADDR(ebase); if (!addr) panic(panic_null_cerr); memcpy((void *)(uncached_ebase + offset), addr, size); } static int __initdata rdhwr_noopt; static int __init set_rdhwr_noopt(char *str) { rdhwr_noopt = 1; return 1; } __setup("rdhwr_noopt", set_rdhwr_noopt); void __init trap_init(void) { extern char except_vec3_generic, except_vec3_r4000; extern char except_vec4; unsigned long i; int rollback; check_wait(); rollback = (cpu_wait == r4k_wait); #if defined(CONFIG_KGDB) if (kgdb_early_setup) return; /* Already done */ #endif if (cpu_has_veic || cpu_has_vint) { unsigned long size = 0x200 + VECTORSPACING*64; ebase = (unsigned long) __alloc_bootmem(size, 1 << fls(size), 0); } else { ebase = CKSEG0; if (cpu_has_mips_r2) ebase += (read_c0_ebase() & 0x3ffff000); } if (board_ebase_setup) board_ebase_setup(); per_cpu_trap_init(true); /* * Copy the generic exception handlers to their final destination. * This will be overriden later as suitable for a particular * configuration. */ set_handler(0x180, &except_vec3_generic, 0x80); /* * Setup default vectors */ for (i = 0; i <= 31; i++) set_except_vector(i, handle_reserved); /* * Copy the EJTAG debug exception vector handler code to it's final * destination. */ if (cpu_has_ejtag && board_ejtag_handler_setup) board_ejtag_handler_setup(); /* * Only some CPUs have the watch exceptions. */ if (cpu_has_watch) set_except_vector(23, handle_watch); /* * Initialise interrupt handlers */ if (cpu_has_veic || cpu_has_vint) { int nvec = cpu_has_veic ? 64 : 8; for (i = 0; i < nvec; i++) set_vi_handler(i, NULL); } else if (cpu_has_divec) set_handler(0x200, &except_vec4, 0x8); /* * Some CPUs can enable/disable for cache parity detection, but does * it different ways. */ parity_protection_init(); /* * The Data Bus Errors / Instruction Bus Errors are signaled * by external hardware. Therefore these two exceptions * may have board specific handlers. */ if (board_be_init) board_be_init(); set_except_vector(0, rollback ? rollback_handle_int : handle_int); set_except_vector(1, handle_tlbm); set_except_vector(2, handle_tlbl); set_except_vector(3, handle_tlbs); set_except_vector(4, handle_adel); set_except_vector(5, handle_ades); set_except_vector(6, handle_ibe); set_except_vector(7, handle_dbe); set_except_vector(8, handle_sys); set_except_vector(9, handle_bp); set_except_vector(10, rdhwr_noopt ? handle_ri : (cpu_has_vtag_icache ? handle_ri_rdhwr_vivt : handle_ri_rdhwr)); set_except_vector(11, handle_cpu); set_except_vector(12, handle_ov); set_except_vector(13, handle_tr); if (current_cpu_type() == CPU_R6000 || current_cpu_type() == CPU_R6000A) { /* * The R6000 is the only R-series CPU that features a machine * check exception (similar to the R4000 cache error) and * unaligned ldc1/sdc1 exception. The handlers have not been * written yet. Well, anyway there is no R6000 machine on the * current list of targets for Linux/MIPS. * (Duh, crap, there is someone with a triple R6k machine) */ //set_except_vector(14, handle_mc); //set_except_vector(15, handle_ndc); } if (board_nmi_handler_setup) board_nmi_handler_setup(); if (cpu_has_fpu && !cpu_has_nofpuex) set_except_vector(15, handle_fpe); set_except_vector(22, handle_mdmx); if (cpu_has_mcheck) set_except_vector(24, handle_mcheck); if (cpu_has_mipsmt) set_except_vector(25, handle_mt); set_except_vector(26, handle_dsp); if (board_cache_error_setup) board_cache_error_setup(); if (cpu_has_vce) /* Special exception: R4[04]00 uses also the divec space. */ memcpy((void *)(ebase + 0x180), &except_vec3_r4000, 0x100); else if (cpu_has_4kex) memcpy((void *)(ebase + 0x180), &except_vec3_generic, 0x80); else memcpy((void *)(ebase + 0x080), &except_vec3_generic, 0x80); local_flush_icache_range(ebase, ebase + 0x400); flush_tlb_handlers(); sort_extable(__start___dbe_table, __stop___dbe_table); cu2_notifier(default_cu2_call, 0x80000000); /* Run last */ }