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 };
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 */
117