arch/arm/include/asm/hw_breakpoint.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ARM_HW_BREAKPOINT_H
   3 #define _ARM_HW_BREAKPOINT_H
   4
   5 #ifdef __KERNEL__
   6
   7 struct task_struct;
   8
   9 #ifdef CONFIG_HAVE_HW_BREAKPOINT
  10
  11 struct arch_hw_breakpoint_ctrl {
  12                 u32 __reserved  : 9,
  13                 mismatch        : 1,
  14                                 : 9,
  15                 len             : 8,
  16                 type            : 2,
  17                 privilege       : 2,
  18                 enabled         : 1;
  19 };
  20
  21 struct arch_hw_breakpoint {
  22         u32     address;
  23         u32     trigger;
  24         struct  arch_hw_breakpoint_ctrl step_ctrl;
  25         struct  arch_hw_breakpoint_ctrl ctrl;
  26 };
  27
  28 static inline u32 encode_ctrl_reg(struct arch_hw_breakpoint_ctrl ctrl)
  29 {
  30         return (ctrl.mismatch << 22) | (ctrl.len << 5) | (ctrl.type << 3) |
  31                 (ctrl.privilege << 1) | ctrl.enabled;
  32 }
  33
  34 static inline void decode_ctrl_reg(u32 reg,
  35                                    struct arch_hw_breakpoint_ctrl *ctrl)
  36 {
  37         ctrl->enabled   = reg & 0x1;
  38         reg >>= 1;
  39         ctrl->privilege = reg & 0x3;
  40         reg >>= 2;
  41         ctrl->type      = reg & 0x3;
  42         reg >>= 2;
  43         ctrl->len       = reg & 0xff;
  44         reg >>= 17;
  45         ctrl->mismatch  = reg & 0x1;
  46 }
  47
  48 /* Debug architecture numbers. */
  49 #define ARM_DEBUG_ARCH_RESERVED 0       /* In case of ptrace ABI updates. */
  50 #define ARM_DEBUG_ARCH_V6       1
  51 #define ARM_DEBUG_ARCH_V6_1     2
  52 #define ARM_DEBUG_ARCH_V7_ECP14 3
  53 #define ARM_DEBUG_ARCH_V7_MM    4
  54 #define ARM_DEBUG_ARCH_V7_1     5
  55 #define ARM_DEBUG_ARCH_V8       6
  56 #define ARM_DEBUG_ARCH_V8_1     7
  57 #define ARM_DEBUG_ARCH_V8_2     8
  58 #define ARM_DEBUG_ARCH_V8_4     9
  59
  60 /* Breakpoint */
  61 #define ARM_BREAKPOINT_EXECUTE  0
  62
  63 /* Watchpoints */
  64 #define ARM_BREAKPOINT_LOAD     1
  65 #define ARM_BREAKPOINT_STORE    2
  66 #define ARM_FSR_ACCESS_MASK     (1 << 11)
  67
  68 /* Privilege Levels */
  69 #define ARM_BREAKPOINT_PRIV     1
  70 #define ARM_BREAKPOINT_USER     2
  71
  72 /* Lengths */
  73 #define ARM_BREAKPOINT_LEN_1    0x1
  74 #define ARM_BREAKPOINT_LEN_2    0x3
  75 #define ARM_BREAKPOINT_LEN_4    0xf
  76 #define ARM_BREAKPOINT_LEN_8    0xff
  77
  78 /* Limits */
  79 #define ARM_MAX_BRP             16
  80 #define ARM_MAX_WRP             16
  81 #define ARM_MAX_HBP_SLOTS       (ARM_MAX_BRP + ARM_MAX_WRP)
  82
  83 /* DSCR method of entry bits. */
  84 #define ARM_DSCR_MOE(x)                 ((x >> 2) & 0xf)
  85 #define ARM_ENTRY_BREAKPOINT            0x1
  86 #define ARM_ENTRY_ASYNC_WATCHPOINT      0x2
  87 #define ARM_ENTRY_SYNC_WATCHPOINT       0xa
  88
  89 /* DSCR monitor/halting bits. */
  90 #define ARM_DSCR_HDBGEN         (1 << 14)
  91 #define ARM_DSCR_MDBGEN         (1 << 15)
  92
  93 /* OSLSR os lock model bits */
  94 #define ARM_OSLSR_OSLM0         (1 << 0)
  95
  96 /* opcode2 numbers for the co-processor instructions. */
  97 #define ARM_OP2_BVR             4
  98 #define ARM_OP2_BCR             5
  99 #define ARM_OP2_WVR             6
 100 #define ARM_OP2_WCR             7
 101
 102 /* Base register numbers for the debug registers. */
 103 #define ARM_BASE_BVR            64
 104 #define ARM_BASE_BCR            80
 105 #define ARM_BASE_WVR            96
 106 #define ARM_BASE_WCR            112
 107
 108 /* Accessor macros for the debug registers. */
 109 #define ARM_DBG_READ(N, M, OP2, VAL) do {\
 110         asm volatile("mrc p14, 0, %0, " #N "," #M ", " #OP2 : "=r" (VAL));\
 111 } while (0)
 112
 113 #define ARM_DBG_WRITE(N, M, OP2, VAL) do {\
 114         asm volatile("mcr p14, 0, %0, " #N "," #M ", " #OP2 : : "r" (VAL));\
 115 } while (0)
 116
 117 struct perf_event_attr;
 118 struct notifier_block;
 119 struct perf_event;
 120 struct pmu;
 121
 122 extern int arch_bp_generic_fields(struct arch_hw_breakpoint_ctrl ctrl,
 123                                   int *gen_len, int *gen_type);
 124 extern int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw);
 125 extern int hw_breakpoint_arch_parse(struct perf_event *bp,
 126                                     const struct perf_event_attr *attr,
 127                                     struct arch_hw_breakpoint *hw);
 128 extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
 129                                            unsigned long val, void *data);
 130
 131 extern u8 arch_get_debug_arch(void);
 132 extern u8 arch_get_max_wp_len(void);
 133 extern void clear_ptrace_hw_breakpoint(struct task_struct *tsk);
 134
 135 int arch_install_hw_breakpoint(struct perf_event *bp);
 136 void arch_uninstall_hw_breakpoint(struct perf_event *bp);
 137 void hw_breakpoint_pmu_read(struct perf_event *bp);
 138 int hw_breakpoint_slots(int type);
 139
 140 #else
 141 static inline void clear_ptrace_hw_breakpoint(struct task_struct *tsk) {}
 142
 143 #endif  /* CONFIG_HAVE_HW_BREAKPOINT */
 144 #endif  /* __KERNEL__ */
 145 #endif  /* _ARM_HW_BREAKPOINT_H */