xref: /linux/include/linux/mmiotrace.h (revision 48dea9a700c8728cc31a1dd44588b97578de86ee)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_MMIOTRACE_H
3 #define _LINUX_MMIOTRACE_H
4 
5 #include <linux/types.h>
6 #include <linux/list.h>
7 
8 struct kmmio_probe;
9 struct pt_regs;
10 
11 typedef void (*kmmio_pre_handler_t)(struct kmmio_probe *,
12 				struct pt_regs *, unsigned long addr);
13 typedef void (*kmmio_post_handler_t)(struct kmmio_probe *,
14 				unsigned long condition, struct pt_regs *);
15 
16 struct kmmio_probe {
17 	/* kmmio internal list: */
18 	struct list_head	list;
19 	/* start location of the probe point: */
20 	unsigned long		addr;
21 	/* length of the probe region: */
22 	unsigned long		len;
23 	/* Called before addr is executed: */
24 	kmmio_pre_handler_t	pre_handler;
25 	/* Called after addr is executed: */
26 	kmmio_post_handler_t	post_handler;
27 	void			*private;
28 };
29 
30 extern unsigned int kmmio_count;
31 
32 extern int register_kmmio_probe(struct kmmio_probe *p);
33 extern void unregister_kmmio_probe(struct kmmio_probe *p);
34 extern int kmmio_init(void);
35 extern void kmmio_cleanup(void);
36 
37 #ifdef CONFIG_MMIOTRACE
38 /* kmmio is active by some kmmio_probes? */
39 static inline int is_kmmio_active(void)
40 {
41 	return kmmio_count;
42 }
43 
44 /* Called from page fault handler. */
45 extern int kmmio_handler(struct pt_regs *regs, unsigned long addr);
46 
47 /* Called from ioremap.c */
48 extern void mmiotrace_ioremap(resource_size_t offset, unsigned long size,
49 							void __iomem *addr);
50 extern void mmiotrace_iounmap(volatile void __iomem *addr);
51 
52 /* For anyone to insert markers. Remember trailing newline. */
53 extern __printf(1, 2) int mmiotrace_printk(const char *fmt, ...);
54 #else /* !CONFIG_MMIOTRACE: */
55 static inline int is_kmmio_active(void)
56 {
57 	return 0;
58 }
59 
60 static inline int kmmio_handler(struct pt_regs *regs, unsigned long addr)
61 {
62 	return 0;
63 }
64 
65 static inline void mmiotrace_ioremap(resource_size_t offset,
66 					unsigned long size, void __iomem *addr)
67 {
68 }
69 
70 static inline void mmiotrace_iounmap(volatile void __iomem *addr)
71 {
72 }
73 
74 static inline __printf(1, 2) int mmiotrace_printk(const char *fmt, ...)
75 {
76 	return 0;
77 }
78 #endif /* CONFIG_MMIOTRACE */
79 
80 enum mm_io_opcode {
81 	MMIO_READ	= 0x1,	/* struct mmiotrace_rw */
82 	MMIO_WRITE	= 0x2,	/* struct mmiotrace_rw */
83 	MMIO_PROBE	= 0x3,	/* struct mmiotrace_map */
84 	MMIO_UNPROBE	= 0x4,	/* struct mmiotrace_map */
85 	MMIO_UNKNOWN_OP = 0x5,	/* struct mmiotrace_rw */
86 };
87 
88 struct mmiotrace_rw {
89 	resource_size_t	phys;	/* PCI address of register */
90 	unsigned long	value;
91 	unsigned long	pc;	/* optional program counter */
92 	int		map_id;
93 	unsigned char	opcode;	/* one of MMIO_{READ,WRITE,UNKNOWN_OP} */
94 	unsigned char	width;	/* size of register access in bytes */
95 };
96 
97 struct mmiotrace_map {
98 	resource_size_t	phys;	/* base address in PCI space */
99 	unsigned long	virt;	/* base virtual address */
100 	unsigned long	len;	/* mapping size */
101 	int		map_id;
102 	unsigned char	opcode;	/* MMIO_PROBE or MMIO_UNPROBE */
103 };
104 
105 /* in kernel/trace/trace_mmiotrace.c */
106 extern void enable_mmiotrace(void);
107 extern void disable_mmiotrace(void);
108 extern void mmio_trace_rw(struct mmiotrace_rw *rw);
109 extern void mmio_trace_mapping(struct mmiotrace_map *map);
110 extern __printf(1, 0) int mmio_trace_printk(const char *fmt, va_list args);
111 
112 #endif /* _LINUX_MMIOTRACE_H */
113