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 };
  21
  22 /* Note: Don't change the first 6 bits below as they are in the same order
  23  * as the dabr and dabrx.
  24  */
  25 #define HW_BRK_TYPE_READ                0x01
  26 #define HW_BRK_TYPE_WRITE               0x02
  27 #define HW_BRK_TYPE_TRANSLATE           0x04
  28 #define HW_BRK_TYPE_USER                0x08
  29 #define HW_BRK_TYPE_KERNEL              0x10
  30 #define HW_BRK_TYPE_HYP                 0x20
  31 #define HW_BRK_TYPE_EXTRANEOUS_IRQ      0x80
  32
  33 /* bits that overlap with the bottom 3 bits of the dabr */
  34 #define HW_BRK_TYPE_RDWR        (HW_BRK_TYPE_READ | HW_BRK_TYPE_WRITE)
  35 #define HW_BRK_TYPE_DABR        (HW_BRK_TYPE_RDWR | HW_BRK_TYPE_TRANSLATE)
  36 #define HW_BRK_TYPE_PRIV_ALL    (HW_BRK_TYPE_USER | HW_BRK_TYPE_KERNEL | \
  37                                  HW_BRK_TYPE_HYP)
  38
  39 /* Minimum granularity */
  40 #ifdef CONFIG_PPC_8xx
  41 #define HW_BREAKPOINT_SIZE  0x4
  42 #else
  43 #define HW_BREAKPOINT_SIZE  0x8
  44 #endif
  45
  46 #define DABR_MAX_LEN    8
  47 #define DAWR_MAX_LEN    512
  48
  49 static inline int nr_wp_slots(void)
  50 {
  51         return cpu_has_feature(CPU_FTR_DAWR1) ? 2 : 1;
  52 }
  53
  54 #ifdef CONFIG_HAVE_HW_BREAKPOINT
  55 #include <linux/kdebug.h>
  56 #include <asm/reg.h>
  57 #include <asm/debug.h>
  58
  59 struct perf_event_attr;
  60 struct perf_event;
  61 struct pmu;
  62 struct perf_sample_data;
  63 struct task_struct;
  64
  65 extern int hw_breakpoint_slots(int type);
  66 extern int arch_bp_generic_fields(int type, int *gen_bp_type);
  67 extern int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw);
  68 extern int hw_breakpoint_arch_parse(struct perf_event *bp,
  69                                     const struct perf_event_attr *attr,
  70                                     struct arch_hw_breakpoint *hw);
  71 extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
  72                                                 unsigned long val, void *data);
  73 int arch_install_hw_breakpoint(struct perf_event *bp);
  74 void arch_uninstall_hw_breakpoint(struct perf_event *bp);
  75 void hw_breakpoint_pmu_read(struct perf_event *bp);
  76 extern void flush_ptrace_hw_breakpoint(struct task_struct *tsk);
  77
  78 extern struct pmu perf_ops_bp;
  79 extern void ptrace_triggered(struct perf_event *bp,
  80                         struct perf_sample_data *data, struct pt_regs *regs);
  81 static inline void hw_breakpoint_disable(void)
  82 {
  83         int i;
  84         struct arch_hw_breakpoint null_brk = {0};
  85
  86         if (!ppc_breakpoint_available())
  87                 return;
  88
  89         for (i = 0; i < nr_wp_slots(); i++)
  90                 __set_breakpoint(i, &null_brk);
  91 }
  92 extern void thread_change_pc(struct task_struct *tsk, struct pt_regs *regs);
  93 int hw_breakpoint_handler(struct die_args *args);
  94
  95 #else   /* CONFIG_HAVE_HW_BREAKPOINT */
  96 static inline void hw_breakpoint_disable(void) { }
  97 static inline void thread_change_pc(struct task_struct *tsk,
  98                                         struct pt_regs *regs) { }
  99
 100 #endif  /* CONFIG_HAVE_HW_BREAKPOINT */
 101
 102
 103 #ifdef CONFIG_PPC_DAWR
 104 extern bool dawr_force_enable;
 105 static inline bool dawr_enabled(void)
 106 {
 107         return dawr_force_enable;
 108 }
 109 int set_dawr(int nr, struct arch_hw_breakpoint *brk);
 110 #else
 111 static inline bool dawr_enabled(void) { return false; }
 112 static inline int set_dawr(int nr, struct arch_hw_breakpoint *brk) { return -1; }
 113 #endif
 114
 115 #endif  /* __KERNEL__ */
 116 #endif  /* _PPC_BOOK3S_64_HW_BREAKPOINT_H */