arch/arm64/include/asm/debug-monitors.h

   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 /*
  38  * BRK instruction encoding
  39  * The #imm16 value should be placed at bits[20:5] within BRK ins
  40  */
  41 #define AARCH64_BREAK_MON       0xd4200000
  42
  43 /*
  44  * BRK instruction for provoking a fault on purpose
  45  * Unlike kgdb, #imm16 value with unallocated handler is used for faulting.
  46  */
  47 #define AARCH64_BREAK_FAULT     (AARCH64_BREAK_MON | (FAULT_BRK_IMM << 5))
  48
  49 #define AARCH64_BREAK_KGDB_DYN_DBG      \
  50         (AARCH64_BREAK_MON | (KGDB_DYN_DBG_BRK_IMM << 5))
  51
  52 #define CACHE_FLUSH_IS_SAFE             1
  53
  54 /* kprobes BRK opcodes with ESR encoding  */
  55 #define BRK64_OPCODE_KPROBES    (AARCH64_BREAK_MON | (KPROBES_BRK_IMM << 5))
  56 #define BRK64_OPCODE_KPROBES_SS (AARCH64_BREAK_MON | (KPROBES_BRK_SS_IMM << 5))
  57 /* uprobes BRK opcodes with ESR encoding  */
  58 #define BRK64_OPCODE_UPROBES    (AARCH64_BREAK_MON | (UPROBES_BRK_IMM << 5))
  59
  60 /* AArch32 */
  61 #define DBG_ESR_EVT_BKPT        0x4
  62 #define DBG_ESR_EVT_VECC        0x5
  63
  64 #define AARCH32_BREAK_ARM       0x07f001f0
  65 #define AARCH32_BREAK_THUMB     0xde01
  66 #define AARCH32_BREAK_THUMB2_LO 0xf7f0
  67 #define AARCH32_BREAK_THUMB2_HI 0xa000
  68
  69 #ifndef __ASSEMBLY__
  70 struct task_struct;
  71
  72 #define DBG_ARCH_ID_RESERVED    0       /* In case of ptrace ABI updates. */
  73
  74 #define DBG_HOOK_HANDLED        0
  75 #define DBG_HOOK_ERROR          1
  76
  77 struct step_hook {
  78         struct list_head node;
  79         int (*fn)(struct pt_regs *regs, unsigned int esr);
  80 };
  81
  82 void register_user_step_hook(struct step_hook *hook);
  83 void unregister_user_step_hook(struct step_hook *hook);
  84
  85 void register_kernel_step_hook(struct step_hook *hook);
  86 void unregister_kernel_step_hook(struct step_hook *hook);
  87
  88 struct break_hook {
  89         struct list_head node;
  90         int (*fn)(struct pt_regs *regs, unsigned int esr);
  91         u16 imm;
  92         u16 mask; /* These bits are ignored when comparing with imm */
  93 };
  94
  95 void register_user_break_hook(struct break_hook *hook);
  96 void unregister_user_break_hook(struct break_hook *hook);
  97
  98 void register_kernel_break_hook(struct break_hook *hook);
  99 void unregister_kernel_break_hook(struct break_hook *hook);
 100
 101 u8 debug_monitors_arch(void);
 102
 103 enum dbg_active_el {
 104         DBG_ACTIVE_EL0 = 0,
 105         DBG_ACTIVE_EL1,
 106 };
 107
 108 void enable_debug_monitors(enum dbg_active_el el);
 109 void disable_debug_monitors(enum dbg_active_el el);
 110
 111 void user_rewind_single_step(struct task_struct *task);
 112 void user_fastforward_single_step(struct task_struct *task);
 113 void user_regs_reset_single_step(struct user_pt_regs *regs,
 114                                  struct task_struct *task);
 115
 116 void kernel_enable_single_step(struct pt_regs *regs);
 117 void kernel_disable_single_step(void);
 118 int kernel_active_single_step(void);
 119
 120 #ifdef CONFIG_HAVE_HW_BREAKPOINT
 121 int reinstall_suspended_bps(struct pt_regs *regs);
 122 #else
 123 static inline int reinstall_suspended_bps(struct pt_regs *regs)
 124 {
 125         return -ENODEV;
 126 }
 127 #endif
 128
 129 int aarch32_break_handler(struct pt_regs *regs);
 130
 131 void debug_traps_init(void);
 132
 133 #endif  /* __ASSEMBLY */
 134 #endif  /* __ASM_DEBUG_MONITORS_H */