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 <prasad@linux.vnet.ibm.com>
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 */
129