xref: /openbmc/linux/arch/arm/include/asm/bug.h (revision 0da85d1e)
1 #ifndef _ASMARM_BUG_H
2 #define _ASMARM_BUG_H
3 
4 #include <linux/linkage.h>
5 #include <linux/types.h>
6 #include <asm/opcodes.h>
7 
8 #ifdef CONFIG_BUG
9 
10 /*
11  * Use a suitable undefined instruction to use for ARM/Thumb2 bug handling.
12  * We need to be careful not to conflict with those used by other modules and
13  * the register_undef_hook() system.
14  */
15 #ifdef CONFIG_THUMB2_KERNEL
16 #define BUG_INSTR_VALUE 0xde02
17 #define BUG_INSTR(__value) __inst_thumb16(__value)
18 #else
19 #define BUG_INSTR_VALUE 0xe7f001f2
20 #define BUG_INSTR(__value) __inst_arm(__value)
21 #endif
22 
23 
24 #define BUG() _BUG(__FILE__, __LINE__, BUG_INSTR_VALUE)
25 #define _BUG(file, line, value) __BUG(file, line, value)
26 
27 #ifdef CONFIG_DEBUG_BUGVERBOSE
28 
29 /*
30  * The extra indirection is to ensure that the __FILE__ string comes through
31  * OK. Many version of gcc do not support the asm %c parameter which would be
32  * preferable to this unpleasantness. We use mergeable string sections to
33  * avoid multiple copies of the string appearing in the kernel image.
34  */
35 
36 #define __BUG(__file, __line, __value)				\
37 do {								\
38 	asm volatile("1:\t" BUG_INSTR(__value) "\n"  \
39 		".pushsection .rodata.str, \"aMS\", %progbits, 1\n" \
40 		"2:\t.asciz " #__file "\n" 			\
41 		".popsection\n" 				\
42 		".pushsection __bug_table,\"a\"\n"		\
43 		"3:\t.word 1b, 2b\n"				\
44 		"\t.hword " #__line ", 0\n"			\
45 		".popsection");					\
46 	unreachable();						\
47 } while (0)
48 
49 #else  /* not CONFIG_DEBUG_BUGVERBOSE */
50 
51 #define __BUG(__file, __line, __value)				\
52 do {								\
53 	asm volatile(BUG_INSTR(__value) "\n");			\
54 	unreachable();						\
55 } while (0)
56 #endif  /* CONFIG_DEBUG_BUGVERBOSE */
57 
58 #define HAVE_ARCH_BUG
59 #endif  /* CONFIG_BUG */
60 
61 #include <asm-generic/bug.h>
62 
63 struct pt_regs;
64 void die(const char *msg, struct pt_regs *regs, int err);
65 
66 struct siginfo;
67 void arm_notify_die(const char *str, struct pt_regs *regs, struct siginfo *info,
68 		unsigned long err, unsigned long trap);
69 
70 #ifdef CONFIG_ARM_LPAE
71 #define FAULT_CODE_ALIGNMENT	33
72 #define FAULT_CODE_DEBUG	34
73 #else
74 #define FAULT_CODE_ALIGNMENT	1
75 #define FAULT_CODE_DEBUG	2
76 #endif
77 
78 void hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int,
79 				       struct pt_regs *),
80 		     int sig, int code, const char *name);
81 
82 void hook_ifault_code(int nr, int (*fn)(unsigned long, unsigned int,
83 				       struct pt_regs *),
84 		     int sig, int code, const char *name);
85 
86 extern asmlinkage void c_backtrace(unsigned long fp, int pmode);
87 
88 struct mm_struct;
89 extern void show_pte(struct mm_struct *mm, unsigned long addr);
90 extern void __show_regs(struct pt_regs *);
91 
92 #endif
93