arch/arm64/include/asm/hw_breakpoint.h

   1 /*
   2  * Copyright (C) 2012 ARM Ltd.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  */
  16 #ifndef __ASM_HW_BREAKPOINT_H
  17 #define __ASM_HW_BREAKPOINT_H
  18
  19 #ifdef __KERNEL__
  20
  21 struct arch_hw_breakpoint_ctrl {
  22         u32 __reserved  : 19,
  23         len             : 8,
  24         type            : 2,
  25         privilege       : 2,
  26         enabled         : 1;
  27 };
  28
  29 struct arch_hw_breakpoint {
  30         u64 address;
  31         u64 trigger;
  32         struct arch_hw_breakpoint_ctrl ctrl;
  33 };
  34
  35 static inline u32 encode_ctrl_reg(struct arch_hw_breakpoint_ctrl ctrl)
  36 {
  37         return (ctrl.len << 5) | (ctrl.type << 3) | (ctrl.privilege << 1) |
  38                 ctrl.enabled;
  39 }
  40
  41 static inline void decode_ctrl_reg(u32 reg,
  42                                    struct arch_hw_breakpoint_ctrl *ctrl)
  43 {
  44         ctrl->enabled   = reg & 0x1;
  45         reg >>= 1;
  46         ctrl->privilege = reg & 0x3;
  47         reg >>= 2;
  48         ctrl->type      = reg & 0x3;
  49         reg >>= 2;
  50         ctrl->len       = reg & 0xff;
  51 }
  52
  53 /* Breakpoint */
  54 #define ARM_BREAKPOINT_EXECUTE  0
  55
  56 /* Watchpoints */
  57 #define ARM_BREAKPOINT_LOAD     1
  58 #define ARM_BREAKPOINT_STORE    2
  59 #define AARCH64_ESR_ACCESS_MASK (1 << 6)
  60
  61 /* Privilege Levels */
  62 #define AARCH64_BREAKPOINT_EL1  1
  63 #define AARCH64_BREAKPOINT_EL0  2
  64
  65 /* Lengths */
  66 #define ARM_BREAKPOINT_LEN_1    0x1
  67 #define ARM_BREAKPOINT_LEN_2    0x3
  68 #define ARM_BREAKPOINT_LEN_4    0xf
  69 #define ARM_BREAKPOINT_LEN_8    0xff
  70
  71 /* Kernel stepping */
  72 #define ARM_KERNEL_STEP_NONE    0
  73 #define ARM_KERNEL_STEP_ACTIVE  1
  74 #define ARM_KERNEL_STEP_SUSPEND 2
  75
  76 /*
  77  * Limits.
  78  * Changing these will require modifications to the register accessors.
  79  */
  80 #define ARM_MAX_BRP             16
  81 #define ARM_MAX_WRP             16
  82
  83 /* Virtual debug register bases. */
  84 #define AARCH64_DBG_REG_BVR     0
  85 #define AARCH64_DBG_REG_BCR     (AARCH64_DBG_REG_BVR + ARM_MAX_BRP)
  86 #define AARCH64_DBG_REG_WVR     (AARCH64_DBG_REG_BCR + ARM_MAX_BRP)
  87 #define AARCH64_DBG_REG_WCR     (AARCH64_DBG_REG_WVR + ARM_MAX_WRP)
  88
  89 /* Debug register names. */
  90 #define AARCH64_DBG_REG_NAME_BVR        "bvr"
  91 #define AARCH64_DBG_REG_NAME_BCR        "bcr"
  92 #define AARCH64_DBG_REG_NAME_WVR        "wvr"
  93 #define AARCH64_DBG_REG_NAME_WCR        "wcr"
  94
  95 /* Accessor macros for the debug registers. */
  96 #define AARCH64_DBG_READ(N, REG, VAL) do {\
  97         asm volatile("mrs %0, dbg" REG #N "_el1" : "=r" (VAL));\
  98 } while (0)
  99
 100 #define AARCH64_DBG_WRITE(N, REG, VAL) do {\
 101         asm volatile("msr dbg" REG #N "_el1, %0" :: "r" (VAL));\
 102 } while (0)
 103
 104 struct task_struct;
 105 struct notifier_block;
 106 struct perf_event;
 107 struct pmu;
 108
 109 extern int arch_bp_generic_fields(struct arch_hw_breakpoint_ctrl ctrl,
 110                                   int *gen_len, int *gen_type);
 111 extern int arch_check_bp_in_kernelspace(struct perf_event *bp);
 112 extern int arch_validate_hwbkpt_settings(struct perf_event *bp);
 113 extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
 114                                            unsigned long val, void *data);
 115
 116 extern int arch_install_hw_breakpoint(struct perf_event *bp);
 117 extern void arch_uninstall_hw_breakpoint(struct perf_event *bp);
 118 extern void hw_breakpoint_pmu_read(struct perf_event *bp);
 119 extern int hw_breakpoint_slots(int type);
 120
 121 #ifdef CONFIG_HAVE_HW_BREAKPOINT
 122 extern void hw_breakpoint_thread_switch(struct task_struct *next);
 123 extern void ptrace_hw_copy_thread(struct task_struct *task);
 124 #else
 125 static inline void hw_breakpoint_thread_switch(struct task_struct *next)
 126 {
 127 }
 128 static inline void ptrace_hw_copy_thread(struct task_struct *task)
 129 {
 130 }
 131 #endif
 132
 133 extern struct pmu perf_ops_bp;
 134
 135 #endif  /* __KERNEL__ */
 136 #endif  /* __ASM_BREAKPOINT_H */