arch/powerpc/include/asm/hw_breakpoint.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * PowerPC BookIII S hardware breakpoint definitions
   4  *
   5  * Copyright 2010, IBM Corporation.
   6  * Author: K.Prasad <[email protected]>
   7  */
   8
   9 #ifndef _PPC_BOOK3S_64_HW_BREAKPOINT_H
  10 #define _PPC_BOOK3S_64_HW_BREAKPOINT_H
  11
  12 #include <asm/cpu_has_feature.h>
  13
  14 #ifdef  __KERNEL__
  15 struct arch_hw_breakpoint {
  16         unsigned long   address;
  17         u16             type;
  18         u16             len; /* length of the target data symbol */
  19         u16             hw_len; /* length programmed in hw */
  20         u8              flags;
  21         bool            perf_single_step; /* temporarily uninstalled for a perf single step */
  22 };
  23
  24 /* Note: Don't change the first 6 bits below as they are in the same order
  25  * as the dabr and dabrx.
  26  */
  27 #define HW_BRK_TYPE_READ                0x01
  28 #define HW_BRK_TYPE_WRITE               0x02
  29 #define HW_BRK_TYPE_TRANSLATE           0x04
  30 #define HW_BRK_TYPE_USER                0x08
  31 #define HW_BRK_TYPE_KERNEL              0x10
  32 #define HW_BRK_TYPE_HYP                 0x20
  33 #define HW_BRK_TYPE_EXTRANEOUS_IRQ      0x80
  34
  35 /* bits that overlap with the bottom 3 bits of the dabr */
  36 #define HW_BRK_TYPE_RDWR        (HW_BRK_TYPE_READ | HW_BRK_TYPE_WRITE)
  37 #define HW_BRK_TYPE_DABR        (HW_BRK_TYPE_RDWR | HW_BRK_TYPE_TRANSLATE)
  38 #define HW_BRK_TYPE_PRIV_ALL    (HW_BRK_TYPE_USER | HW_BRK_TYPE_KERNEL | \
  39                                  HW_BRK_TYPE_HYP)
  40
  41 #define HW_BRK_FLAG_DISABLED    0x1
  42
  43 /* Minimum granularity */
  44 #ifdef CONFIG_PPC_8xx
  45 #define HW_BREAKPOINT_SIZE  0x4
  46 #else
  47 #define HW_BREAKPOINT_SIZE  0x8
  48 #endif
  49 #define HW_BREAKPOINT_SIZE_QUADWORD     0x10
  50
  51 #define DABR_MAX_LEN    8
  52 #define DAWR_MAX_LEN    512
  53
  54 static inline int nr_wp_slots(void)
  55 {
  56         return cpu_has_feature(CPU_FTR_DAWR1) ? 2 : 1;
  57 }
  58
  59 bool wp_check_constraints(struct pt_regs *regs, ppc_inst_t instr,
  60                           unsigned long ea, int type, int size,
  61                           struct arch_hw_breakpoint *info);
  62
  63 void wp_get_instr_detail(struct pt_regs *regs, ppc_inst_t *instr,
  64                          int *type, int *size, unsigned long *ea);
  65
  66 #ifdef CONFIG_HAVE_HW_BREAKPOINT
  67 #include <linux/kdebug.h>
  68 #include <asm/reg.h>
  69 #include <asm/debug.h>
  70
  71 struct perf_event_attr;
  72 struct perf_event;
  73 struct pmu;
  74 struct perf_sample_data;
  75 struct task_struct;
  76
  77 extern int hw_breakpoint_slots(int type);
  78 extern int arch_bp_generic_fields(int type, int *gen_bp_type);
  79 extern int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw);
  80 extern int hw_breakpoint_arch_parse(struct perf_event *bp,
  81                                     const struct perf_event_attr *attr,
  82                                     struct arch_hw_breakpoint *hw);
  83 extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
  84                                                 unsigned long val, void *data);
  85 int arch_install_hw_breakpoint(struct perf_event *bp);
  86 void arch_uninstall_hw_breakpoint(struct perf_event *bp);
  87 void hw_breakpoint_pmu_read(struct perf_event *bp);
  88 extern void flush_ptrace_hw_breakpoint(struct task_struct *tsk);
  89
  90 extern struct pmu perf_ops_bp;
  91 extern void ptrace_triggered(struct perf_event *bp,
  92                         struct perf_sample_data *data, struct pt_regs *regs);
  93 static inline void hw_breakpoint_disable(void)
  94 {
  95         int i;
  96         struct arch_hw_breakpoint null_brk = {0};
  97
  98         if (!ppc_breakpoint_available())
  99                 return;
 100
 101         for (i = 0; i < nr_wp_slots(); i++)
 102                 __set_breakpoint(i, &null_brk);
 103 }
 104 extern void thread_change_pc(struct task_struct *tsk, struct pt_regs *regs);
 105 int hw_breakpoint_handler(struct die_args *args);
 106
 107 #else   /* CONFIG_HAVE_HW_BREAKPOINT */
 108 static inline void hw_breakpoint_disable(void) { }
 109 static inline void thread_change_pc(struct task_struct *tsk,
 110                                         struct pt_regs *regs) { }
 111
 112 #endif  /* CONFIG_HAVE_HW_BREAKPOINT */
 113
 114
 115 #ifdef CONFIG_PPC_DAWR
 116 extern bool dawr_force_enable;
 117 static inline bool dawr_enabled(void)
 118 {
 119         return dawr_force_enable;
 120 }
 121 int set_dawr(int nr, struct arch_hw_breakpoint *brk);
 122 #else
 123 static inline bool dawr_enabled(void) { return false; }
 124 static inline int set_dawr(int nr, struct arch_hw_breakpoint *brk) { return -1; }
 125 #endif
 126
 127 #endif  /* __KERNEL__ */
 128 #endif  /* _PPC_BOOK3S_64_HW_BREAKPOINT_H */