diff options
Diffstat (limited to 'arch/csky/kernel/traps.c')
| -rw-r--r-- | arch/csky/kernel/traps.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/arch/csky/kernel/traps.c b/arch/csky/kernel/traps.c new file mode 100644 index 000000000..6e426fba0 --- /dev/null +++ b/arch/csky/kernel/traps.c @@ -0,0 +1,262 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. + +#include <linux/sched.h> +#include <linux/signal.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/user.h> +#include <linux/string.h> +#include <linux/linkage.h> +#include <linux/init.h> +#include <linux/ptrace.h> +#include <linux/kallsyms.h> +#include <linux/rtc.h> +#include <linux/uaccess.h> +#include <linux/kprobes.h> +#include <linux/kdebug.h> +#include <linux/sched/debug.h> + +#include <asm/setup.h> +#include <asm/traps.h> +#include <asm/pgalloc.h> +#include <asm/siginfo.h> + +#include <asm/mmu_context.h> + +#ifdef CONFIG_CPU_HAS_FPU +#include <abi/fpu.h> +#endif + +int show_unhandled_signals = 1; + +/* Defined in entry.S */ +asmlinkage void csky_trap(void); + +asmlinkage void csky_systemcall(void); +asmlinkage void csky_cmpxchg(void); +asmlinkage void csky_get_tls(void); +asmlinkage void csky_irq(void); + +asmlinkage void csky_pagefault(void); + +/* Defined in head.S */ +asmlinkage void _start_smp_secondary(void); + +void __init pre_trap_init(void) +{ + int i; + + mtcr("vbr", vec_base); + + for (i = 1; i < 128; i++) + VEC_INIT(i, csky_trap); +} + +void __init trap_init(void) +{ + VEC_INIT(VEC_AUTOVEC, csky_irq); + + /* setup trap0 trap2 trap3 */ + VEC_INIT(VEC_TRAP0, csky_systemcall); + VEC_INIT(VEC_TRAP2, csky_cmpxchg); + VEC_INIT(VEC_TRAP3, csky_get_tls); + + /* setup MMU TLB exception */ + VEC_INIT(VEC_TLBINVALIDL, csky_pagefault); + VEC_INIT(VEC_TLBINVALIDS, csky_pagefault); + VEC_INIT(VEC_TLBMODIFIED, csky_pagefault); + +#ifdef CONFIG_CPU_HAS_FPU + init_fpu(); +#endif + +#ifdef CONFIG_SMP + mtcr("cr<28, 0>", virt_to_phys(vec_base)); + + VEC_INIT(VEC_RESET, (void *)virt_to_phys(_start_smp_secondary)); +#endif +} + +static DEFINE_SPINLOCK(die_lock); + +void die(struct pt_regs *regs, const char *str) +{ + static int die_counter; + int ret; + + oops_enter(); + + spin_lock_irq(&die_lock); + console_verbose(); + bust_spinlocks(1); + + pr_emerg("%s [#%d]\n", str, ++die_counter); + print_modules(); + show_regs(regs); + show_stack(current, (unsigned long *)regs->regs[4], KERN_INFO); + + ret = notify_die(DIE_OOPS, str, regs, 0, trap_no(regs), SIGSEGV); + + bust_spinlocks(0); + add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); + spin_unlock_irq(&die_lock); + oops_exit(); + + if (in_interrupt()) + panic("Fatal exception in interrupt"); + if (panic_on_oops) + panic("Fatal exception"); + if (ret != NOTIFY_STOP) + make_task_dead(SIGSEGV); +} + +void do_trap(struct pt_regs *regs, int signo, int code, unsigned long addr) +{ + struct task_struct *tsk = current; + + if (show_unhandled_signals && unhandled_signal(tsk, signo) + && printk_ratelimit()) { + pr_info("%s[%d]: unhandled signal %d code 0x%x at 0x%08lx", + tsk->comm, task_pid_nr(tsk), signo, code, addr); + print_vma_addr(KERN_CONT " in ", instruction_pointer(regs)); + pr_cont("\n"); + show_regs(regs); + } + + force_sig_fault(signo, code, (void __user *)addr); +} + +static void do_trap_error(struct pt_regs *regs, int signo, int code, + unsigned long addr, const char *str) +{ + current->thread.trap_no = trap_no(regs); + + if (user_mode(regs)) { + do_trap(regs, signo, code, addr); + } else { + if (!fixup_exception(regs)) + die(regs, str); + } +} + +#define DO_ERROR_INFO(name, signo, code, str) \ +asmlinkage __visible void name(struct pt_regs *regs) \ +{ \ + do_trap_error(regs, signo, code, regs->pc, "Oops - " str); \ +} + +DO_ERROR_INFO(do_trap_unknown, + SIGILL, ILL_ILLTRP, "unknown exception"); +DO_ERROR_INFO(do_trap_zdiv, + SIGFPE, FPE_INTDIV, "error zero div exception"); +DO_ERROR_INFO(do_trap_buserr, + SIGSEGV, ILL_ILLADR, "error bus error exception"); + +asmlinkage void do_trap_misaligned(struct pt_regs *regs) +{ +#ifdef CONFIG_CPU_NEED_SOFTALIGN + csky_alignment(regs); +#else + current->thread.trap_no = trap_no(regs); + do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->pc, + "Oops - load/store address misaligned"); +#endif +} + +asmlinkage void do_trap_bkpt(struct pt_regs *regs) +{ +#ifdef CONFIG_KPROBES + if (kprobe_single_step_handler(regs)) + return; +#endif +#ifdef CONFIG_UPROBES + if (uprobe_single_step_handler(regs)) + return; +#endif + if (user_mode(regs)) { + send_sig(SIGTRAP, current, 0); + return; + } + + do_trap_error(regs, SIGILL, ILL_ILLTRP, regs->pc, + "Oops - illegal trap exception"); +} + +asmlinkage void do_trap_illinsn(struct pt_regs *regs) +{ + current->thread.trap_no = trap_no(regs); + +#ifdef CONFIG_KPROBES + if (kprobe_breakpoint_handler(regs)) + return; +#endif +#ifdef CONFIG_UPROBES + if (uprobe_breakpoint_handler(regs)) + return; +#endif +#ifndef CONFIG_CPU_NO_USER_BKPT + if (*(uint16_t *)instruction_pointer(regs) != USR_BKPT) { + send_sig(SIGTRAP, current, 0); + return; + } +#endif + + do_trap_error(regs, SIGILL, ILL_ILLOPC, regs->pc, + "Oops - illegal instruction exception"); +} + +asmlinkage void do_trap_fpe(struct pt_regs *regs) +{ +#ifdef CONFIG_CPU_HAS_FPU + return fpu_fpe(regs); +#else + do_trap_error(regs, SIGILL, ILL_ILLOPC, regs->pc, + "Oops - fpu instruction exception"); +#endif +} + +asmlinkage void do_trap_priv(struct pt_regs *regs) +{ +#ifdef CONFIG_CPU_HAS_FPU + if (user_mode(regs) && fpu_libc_helper(regs)) + return; +#endif + do_trap_error(regs, SIGILL, ILL_PRVOPC, regs->pc, + "Oops - illegal privileged exception"); +} + +asmlinkage void trap_c(struct pt_regs *regs) +{ + switch (trap_no(regs)) { + case VEC_ZERODIV: + do_trap_zdiv(regs); + break; + case VEC_TRACE: + do_trap_bkpt(regs); + break; + case VEC_ILLEGAL: + do_trap_illinsn(regs); + break; + case VEC_TRAP1: + case VEC_BREAKPOINT: + do_trap_bkpt(regs); + break; + case VEC_ACCESS: + do_trap_buserr(regs); + break; + case VEC_ALIGN: + do_trap_misaligned(regs); + break; + case VEC_FPE: + do_trap_fpe(regs); + break; + case VEC_PRIV: + do_trap_priv(regs); + break; + default: + do_trap_unknown(regs); + break; + } +} |