xref: /openbmc/linux/arch/arm/include/asm/bug.h (revision f3539c12)
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 /*
9  * Use a suitable undefined instruction to use for ARM/Thumb2 bug handling.
10  * We need to be careful not to conflict with those used by other modules and
11  * the register_undef_hook() system.
12  */
13 #ifdef CONFIG_THUMB2_KERNEL
14 #define BUG_INSTR_VALUE 0xde02
15 #define BUG_INSTR(__value) __inst_thumb16(__value)
16 #else
17 #define BUG_INSTR_VALUE 0xe7f001f2
18 #define BUG_INSTR(__value) __inst_arm(__value)
19 #endif
20 
21 
22 #define BUG() _BUG(__FILE__, __LINE__, BUG_INSTR_VALUE)
23 #define _BUG(file, line, value) __BUG(file, line, value)
24 
25 #ifdef CONFIG_DEBUG_BUGVERBOSE
26 
27 /*
28  * The extra indirection is to ensure that the __FILE__ string comes through
29  * OK. Many version of gcc do not support the asm %c parameter which would be
30  * preferable to this unpleasantness. We use mergeable string sections to
31  * avoid multiple copies of the string appearing in the kernel image.
32  */
33 
34 #define __BUG(__file, __line, __value)				\
35 do {								\
36 	asm volatile("1:\t" BUG_INSTR(__value) "\n"  \
37 		".pushsection .rodata.str, \"aMS\", %progbits, 1\n" \
38 		"2:\t.asciz " #__file "\n" 			\
39 		".popsection\n" 				\
40 		".pushsection __bug_table,\"a\"\n"		\
41 		".align 2\n"					\
42 		"3:\t.word 1b, 2b\n"				\
43 		"\t.hword " #__line ", 0\n"			\
44 		".popsection");					\
45 	unreachable();						\
46 } while (0)
47 
48 #else
49 
50 #define __BUG(__file, __line, __value)				\
51 do {								\
52 	asm volatile(BUG_INSTR(__value) "\n");			\
53 	unreachable();						\
54 } while (0)
55 #endif  /* CONFIG_DEBUG_BUGVERBOSE */
56 
57 #define HAVE_ARCH_BUG
58 
59 #include <asm-generic/bug.h>
60 
61 struct pt_regs;
62 void die(const char *msg, struct pt_regs *regs, int err);
63 
64 struct siginfo;
65 void arm_notify_die(const char *str, struct pt_regs *regs, struct siginfo *info,
66 		unsigned long err, unsigned long trap);
67 
68 #ifdef CONFIG_ARM_LPAE
69 #define FAULT_CODE_ALIGNMENT	33
70 #define FAULT_CODE_DEBUG	34
71 #else
72 #define FAULT_CODE_ALIGNMENT	1
73 #define FAULT_CODE_DEBUG	2
74 #endif
75 
76 void hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int,
77 				       struct pt_regs *),
78 		     int sig, int code, const char *name);
79 
80 void hook_ifault_code(int nr, int (*fn)(unsigned long, unsigned int,
81 				       struct pt_regs *),
82 		     int sig, int code, const char *name);
83 
84 extern asmlinkage void c_backtrace(unsigned long fp, int pmode);
85 
86 struct mm_struct;
87 extern void show_pte(struct mm_struct *mm, unsigned long addr);
88 extern void __show_regs(struct pt_regs *);
89 
90 #endif
91