1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
4 #include <linux/sched.h>
5 #include <linux/signal.h>
6 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/user.h>
10 #include <linux/string.h>
11 #include <linux/linkage.h>
12 #include <linux/init.h>
13 #include <linux/ptrace.h>
14 #include <linux/kallsyms.h>
15 #include <linux/rtc.h>
16 #include <linux/uaccess.h>
17 #include <linux/kprobes.h>
18 #include <linux/kdebug.h>
19 #include <linux/sched/debug.h>
21 #include <asm/setup.h>
22 #include <asm/traps.h>
23 #include <asm/pgalloc.h>
24 #include <asm/siginfo.h>
26 #include <asm/mmu_context.h>
28 #ifdef CONFIG_CPU_HAS_FPU
32 int show_unhandled_signals = 1;
34 /* Defined in entry.S */
35 asmlinkage void csky_trap(void);
37 asmlinkage void csky_systemcall(void);
38 asmlinkage void csky_cmpxchg(void);
39 asmlinkage void csky_get_tls(void);
40 asmlinkage void csky_irq(void);
42 asmlinkage void csky_tlbinvalidl(void);
43 asmlinkage void csky_tlbinvalids(void);
44 asmlinkage void csky_tlbmodified(void);
46 /* Defined in head.S */
47 asmlinkage void _start_smp_secondary(void);
49 void __init pre_trap_init(void)
53 mtcr("vbr", vec_base);
55 for (i = 1; i < 128; i++)
56 VEC_INIT(i, csky_trap);
59 void __init trap_init(void)
61 VEC_INIT(VEC_AUTOVEC, csky_irq);
63 /* setup trap0 trap2 trap3 */
64 VEC_INIT(VEC_TRAP0, csky_systemcall);
65 VEC_INIT(VEC_TRAP2, csky_cmpxchg);
66 VEC_INIT(VEC_TRAP3, csky_get_tls);
68 /* setup MMU TLB exception */
69 VEC_INIT(VEC_TLBINVALIDL, csky_tlbinvalidl);
70 VEC_INIT(VEC_TLBINVALIDS, csky_tlbinvalids);
71 VEC_INIT(VEC_TLBMODIFIED, csky_tlbmodified);
73 #ifdef CONFIG_CPU_HAS_FPU
78 mtcr("cr<28, 0>", virt_to_phys(vec_base));
80 VEC_INIT(VEC_RESET, (void *)virt_to_phys(_start_smp_secondary));
84 static DEFINE_SPINLOCK(die_lock);
86 void die(struct pt_regs *regs, const char *str)
88 static int die_counter;
93 spin_lock_irq(&die_lock);
97 pr_emerg("%s [#%d]\n", str, ++die_counter);
100 show_stack(current, (unsigned long *)regs->regs[4], KERN_INFO);
102 ret = notify_die(DIE_OOPS, str, regs, 0, trap_no(regs), SIGSEGV);
105 add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
106 spin_unlock_irq(&die_lock);
110 panic("Fatal exception in interrupt");
112 panic("Fatal exception");
113 if (ret != NOTIFY_STOP)
114 make_task_dead(SIGSEGV);
117 void do_trap(struct pt_regs *regs, int signo, int code, unsigned long addr)
119 struct task_struct *tsk = current;
121 if (show_unhandled_signals && unhandled_signal(tsk, signo)
122 && printk_ratelimit()) {
123 pr_info("%s[%d]: unhandled signal %d code 0x%x at 0x%08lx",
124 tsk->comm, task_pid_nr(tsk), signo, code, addr);
125 print_vma_addr(KERN_CONT " in ", instruction_pointer(regs));
130 force_sig_fault(signo, code, (void __user *)addr);
133 static void do_trap_error(struct pt_regs *regs, int signo, int code,
134 unsigned long addr, const char *str)
136 current->thread.trap_no = trap_no(regs);
138 if (user_mode(regs)) {
139 do_trap(regs, signo, code, addr);
141 if (!fixup_exception(regs))
146 #define DO_ERROR_INFO(name, signo, code, str) \
147 asmlinkage __visible void name(struct pt_regs *regs) \
149 do_trap_error(regs, signo, code, regs->pc, "Oops - " str); \
152 DO_ERROR_INFO(do_trap_unknown,
153 SIGILL, ILL_ILLTRP, "unknown exception");
154 DO_ERROR_INFO(do_trap_zdiv,
155 SIGFPE, FPE_INTDIV, "error zero div exception");
156 DO_ERROR_INFO(do_trap_buserr,
157 SIGSEGV, ILL_ILLADR, "error bus error exception");
159 asmlinkage void do_trap_misaligned(struct pt_regs *regs)
161 #ifdef CONFIG_CPU_NEED_SOFTALIGN
162 csky_alignment(regs);
164 current->thread.trap_no = trap_no(regs);
165 do_trap_error(regs, SIGBUS, BUS_ADRALN, regs->pc,
166 "Oops - load/store address misaligned");
170 asmlinkage void do_trap_bkpt(struct pt_regs *regs)
172 #ifdef CONFIG_KPROBES
173 if (kprobe_single_step_handler(regs))
176 #ifdef CONFIG_UPROBES
177 if (uprobe_single_step_handler(regs))
180 if (user_mode(regs)) {
181 send_sig(SIGTRAP, current, 0);
185 do_trap_error(regs, SIGILL, ILL_ILLTRP, regs->pc,
186 "Oops - illegal trap exception");
189 asmlinkage void do_trap_illinsn(struct pt_regs *regs)
191 current->thread.trap_no = trap_no(regs);
193 #ifdef CONFIG_KPROBES
194 if (kprobe_breakpoint_handler(regs))
197 #ifdef CONFIG_UPROBES
198 if (uprobe_breakpoint_handler(regs))
201 #ifndef CONFIG_CPU_NO_USER_BKPT
202 if (*(uint16_t *)instruction_pointer(regs) != USR_BKPT) {
203 send_sig(SIGTRAP, current, 0);
208 do_trap_error(regs, SIGILL, ILL_ILLOPC, regs->pc,
209 "Oops - illegal instruction exception");
212 asmlinkage void do_trap_fpe(struct pt_regs *regs)
214 #ifdef CONFIG_CPU_HAS_FPU
215 return fpu_fpe(regs);
217 do_trap_error(regs, SIGILL, ILL_ILLOPC, regs->pc,
218 "Oops - fpu instruction exception");
222 asmlinkage void do_trap_priv(struct pt_regs *regs)
224 #ifdef CONFIG_CPU_HAS_FPU
225 if (user_mode(regs) && fpu_libc_helper(regs))
228 do_trap_error(regs, SIGILL, ILL_PRVOPC, regs->pc,
229 "Oops - illegal privileged exception");
232 asmlinkage void trap_c(struct pt_regs *regs)
234 switch (trap_no(regs)) {
242 do_trap_illinsn(regs);
249 do_trap_buserr(regs);
252 do_trap_misaligned(regs);
261 do_trap_unknown(regs);