summaryrefslogtreecommitdiff
path: root/arch/arm64/include/asm/debug-monitors.h
blob: 4b6b3f72a2158a06e07f36529912c81c0b5fb43b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
/*
 * Copyright (C) 2012 ARM Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
#ifndef __ASM_DEBUG_MONITORS_H
#define __ASM_DEBUG_MONITORS_H

#ifdef __KERNEL__

#include <linux/errno.h>
#include <linux/types.h>
#include <asm/brk-imm.h>
#include <asm/esr.h>
#include <asm/insn.h>
#include <asm/ptrace.h>

/* Low-level stepping controls. */
#define DBG_MDSCR_SS		(1 << 0)
#define DBG_SPSR_SS		(1 << 21)

/* MDSCR_EL1 enabling bits */
#define DBG_MDSCR_KDE		(1 << 13)
#define DBG_MDSCR_MDE		(1 << 15)
#define DBG_MDSCR_MASK		~(DBG_MDSCR_KDE | DBG_MDSCR_MDE)

#define	DBG_ESR_EVT(x)		(((x) >> 27) & 0x7)

/* AArch64 */
#define DBG_ESR_EVT_HWBP	0x0
#define DBG_ESR_EVT_HWSS	0x1
#define DBG_ESR_EVT_HWWP	0x2
#define DBG_ESR_EVT_BRK		0x6

/*
 * Break point instruction encoding
 */
#define BREAK_INSTR_SIZE		AARCH64_INSN_SIZE

/*
 * BRK instruction encoding
 * The #imm16 value should be placed at bits[20:5] within BRK ins
 */
#define AARCH64_BREAK_MON	0xd4200000

/*
 * BRK instruction for provoking a fault on purpose
 * Unlike kgdb, #imm16 value with unallocated handler is used for faulting.
 */
#define AARCH64_BREAK_FAULT	(AARCH64_BREAK_MON | (FAULT_BRK_IMM << 5))

#define AARCH64_BREAK_KGDB_DYN_DBG	\
	(AARCH64_BREAK_MON | (KGDB_DYN_DBG_BRK_IMM << 5))
#define KGDB_DYN_BRK_INS_BYTE(x)	\
	((AARCH64_BREAK_KGDB_DYN_DBG >> (8 * (x))) & 0xff)

#define CACHE_FLUSH_IS_SAFE		1

/* kprobes BRK opcodes with ESR encoding  */
#define BRK64_ESR_MASK		0xFFFF
#define BRK64_ESR_KPROBES	0x0004
#define BRK64_OPCODE_KPROBES	(AARCH64_BREAK_MON | (BRK64_ESR_KPROBES << 5))

/* AArch32 */
#define DBG_ESR_EVT_BKPT	0x4
#define DBG_ESR_EVT_VECC	0x5

#define AARCH32_BREAK_ARM	0x07f001f0
#define AARCH32_BREAK_THUMB	0xde01
#define AARCH32_BREAK_THUMB2_LO	0xf7f0
#define AARCH32_BREAK_THUMB2_HI	0xa000

#ifndef __ASSEMBLY__
struct task_struct;

#define DBG_ARCH_ID_RESERVED	0	/* In case of ptrace ABI updates. */

#define DBG_HOOK_HANDLED	0
#define DBG_HOOK_ERROR		1

struct step_hook {
	struct list_head node;
	int (*fn)(struct pt_regs *regs, unsigned int esr);
};

void register_step_hook(struct step_hook *hook);
void unregister_step_hook(struct step_hook *hook);

struct break_hook {
	struct list_head node;
	u32 esr_val;
	u32 esr_mask;
	int (*fn)(struct pt_regs *regs, unsigned int esr);
};

void register_break_hook(struct break_hook *hook);
void unregister_break_hook(struct break_hook *hook);

u8 debug_monitors_arch(void);

enum dbg_active_el {
	DBG_ACTIVE_EL0 = 0,
	DBG_ACTIVE_EL1,
};

void enable_debug_monitors(enum dbg_active_el el);
void disable_debug_monitors(enum dbg_active_el el);

void user_rewind_single_step(struct task_struct *task);
void user_fastforward_single_step(struct task_struct *task);

void kernel_enable_single_step(struct pt_regs *regs);
void kernel_disable_single_step(void);
int kernel_active_single_step(void);

#ifdef CONFIG_HAVE_HW_BREAKPOINT
int reinstall_suspended_bps(struct pt_regs *regs);
#else
static inline int reinstall_suspended_bps(struct pt_regs *regs)
{
	return -ENODEV;
}
#endif

int aarch32_break_handler(struct pt_regs *regs);

#endif	/* __ASSEMBLY */
#endif	/* __KERNEL__ */
#endif	/* __ASM_DEBUG_MONITORS_H */