1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2012 ARM Ltd.
4  */
5 #ifndef __ASM_DEBUG_MONITORS_H
6 #define __ASM_DEBUG_MONITORS_H
7 
8 #include <linux/errno.h>
9 #include <linux/types.h>
10 #include <asm/brk-imm.h>
11 #include <asm/esr.h>
12 #include <asm/insn.h>
13 #include <asm/ptrace.h>
14 
15 /* Low-level stepping controls. */
16 #define DBG_MDSCR_SS		(1 << 0)
17 #define DBG_SPSR_SS		(1 << 21)
18 
19 /* MDSCR_EL1 enabling bits */
20 #define DBG_MDSCR_KDE		(1 << 13)
21 #define DBG_MDSCR_MDE		(1 << 15)
22 #define DBG_MDSCR_MASK		~(DBG_MDSCR_KDE | DBG_MDSCR_MDE)
23 
24 #define	DBG_ESR_EVT(x)		(((x) >> 27) & 0x7)
25 
26 /* AArch64 */
27 #define DBG_ESR_EVT_HWBP	0x0
28 #define DBG_ESR_EVT_HWSS	0x1
29 #define DBG_ESR_EVT_HWWP	0x2
30 #define DBG_ESR_EVT_BRK		0x6
31 
32 /*
33  * Break point instruction encoding
34  */
35 #define BREAK_INSTR_SIZE		AARCH64_INSN_SIZE
36 
37 #define AARCH64_BREAK_KGDB_DYN_DBG	\
38 	(AARCH64_BREAK_MON | (KGDB_DYN_DBG_BRK_IMM << 5))
39 
40 #define CACHE_FLUSH_IS_SAFE		1
41 
42 /* kprobes BRK opcodes with ESR encoding  */
43 #define BRK64_OPCODE_KPROBES	(AARCH64_BREAK_MON | (KPROBES_BRK_IMM << 5))
44 #define BRK64_OPCODE_KPROBES_SS	(AARCH64_BREAK_MON | (KPROBES_BRK_SS_IMM << 5))
45 /* uprobes BRK opcodes with ESR encoding  */
46 #define BRK64_OPCODE_UPROBES	(AARCH64_BREAK_MON | (UPROBES_BRK_IMM << 5))
47 
48 /* AArch32 */
49 #define DBG_ESR_EVT_BKPT	0x4
50 #define DBG_ESR_EVT_VECC	0x5
51 
52 #define AARCH32_BREAK_ARM	0x07f001f0
53 #define AARCH32_BREAK_THUMB	0xde01
54 #define AARCH32_BREAK_THUMB2_LO	0xf7f0
55 #define AARCH32_BREAK_THUMB2_HI	0xa000
56 
57 #ifndef __ASSEMBLY__
58 struct task_struct;
59 
60 #define DBG_ARCH_ID_RESERVED	0	/* In case of ptrace ABI updates. */
61 
62 #define DBG_HOOK_HANDLED	0
63 #define DBG_HOOK_ERROR		1
64 
65 struct step_hook {
66 	struct list_head node;
67 	int (*fn)(struct pt_regs *regs, unsigned long esr);
68 };
69 
70 void register_user_step_hook(struct step_hook *hook);
71 void unregister_user_step_hook(struct step_hook *hook);
72 
73 void register_kernel_step_hook(struct step_hook *hook);
74 void unregister_kernel_step_hook(struct step_hook *hook);
75 
76 struct break_hook {
77 	struct list_head node;
78 	int (*fn)(struct pt_regs *regs, unsigned long esr);
79 	u16 imm;
80 	u16 mask; /* These bits are ignored when comparing with imm */
81 };
82 
83 void register_user_break_hook(struct break_hook *hook);
84 void unregister_user_break_hook(struct break_hook *hook);
85 
86 void register_kernel_break_hook(struct break_hook *hook);
87 void unregister_kernel_break_hook(struct break_hook *hook);
88 
89 u8 debug_monitors_arch(void);
90 
91 enum dbg_active_el {
92 	DBG_ACTIVE_EL0 = 0,
93 	DBG_ACTIVE_EL1,
94 };
95 
96 void enable_debug_monitors(enum dbg_active_el el);
97 void disable_debug_monitors(enum dbg_active_el el);
98 
99 void user_rewind_single_step(struct task_struct *task);
100 void user_fastforward_single_step(struct task_struct *task);
101 void user_regs_reset_single_step(struct user_pt_regs *regs,
102 				 struct task_struct *task);
103 
104 void kernel_enable_single_step(struct pt_regs *regs);
105 void kernel_disable_single_step(void);
106 int kernel_active_single_step(void);
107 void kernel_rewind_single_step(struct pt_regs *regs);
108 
109 #ifdef CONFIG_HAVE_HW_BREAKPOINT
110 int reinstall_suspended_bps(struct pt_regs *regs);
111 #else
reinstall_suspended_bps(struct pt_regs * regs)112 static inline int reinstall_suspended_bps(struct pt_regs *regs)
113 {
114 	return -ENODEV;
115 }
116 #endif
117 
118 int aarch32_break_handler(struct pt_regs *regs);
119 
120 void debug_traps_init(void);
121 
122 #endif	/* __ASSEMBLY */
123 #endif	/* __ASM_DEBUG_MONITORS_H */
124