xref: /openbmc/u-boot/include/iotrace.h (revision 4a2b2724)
1 /*
2  * Copyright (c) 2014 Google, Inc.
3  *
4  * SPDX-License-Identifier:     GPL-2.0+
5  */
6 
7 #ifndef __IOTRACE_H
8 #define __IOTRACE_H
9 
10 #include <linux/types.h>
11 
12 /*
13  * This file is designed to be included in arch/<arch>/include/asm/io.h.
14  * It redirects all IO access through a tracing/checksumming feature for
15  * testing purposes.
16  */
17 
18 #if defined(CONFIG_IO_TRACE) && !defined(IOTRACE_IMPL) && \
19 	!defined(CONFIG_SPL_BUILD)
20 
21 #undef readl
22 #define readl(addr)	iotrace_readl((const void *)(addr))
23 
24 #undef writel
25 #define writel(val, addr)	iotrace_writel(val, (const void *)(addr))
26 
27 #undef readw
28 #define readw(addr)	iotrace_readw((const void *)(addr))
29 
30 #undef writew
31 #define writew(val, addr)	iotrace_writew(val, (const void *)(addr))
32 
33 #undef readb
34 #define readb(addr)	iotrace_readb((const void *)(uintptr_t)addr)
35 
36 #undef writeb
37 #define writeb(val, addr) \
38 	iotrace_writeb(val, (const void *)(uintptr_t)addr)
39 
40 #endif
41 
42 /* Tracing functions which mirror their io.h counterparts */
43 u32 iotrace_readl(const void *ptr);
44 void iotrace_writel(ulong value, const void *ptr);
45 u16 iotrace_readw(const void *ptr);
46 void iotrace_writew(ulong value, const void *ptr);
47 u8 iotrace_readb(const void *ptr);
48 void iotrace_writeb(ulong value, const void *ptr);
49 
50 /**
51  * iotrace_reset_checksum() - Reset the iotrace checksum
52  */
53 void iotrace_reset_checksum(void);
54 
55 /**
56  * iotrace_get_checksum() - Get the current checksum value
57  *
58  * @return currect checksum value
59  */
60 u32 iotrace_get_checksum(void);
61 
62 /**
63  * iotrace_set_enabled() - Set whether iotracing is enabled or not
64  *
65  * This controls whether the checksum is updated and a trace record added
66  * for each I/O access.
67  *
68  * @enable: true to enable iotracing, false to disable
69  */
70 void iotrace_set_enabled(int enable);
71 
72 /**
73  * iotrace_get_enabled() - Get whether iotracing is enabled or not
74  *
75  * @return true if enabled, false if disabled
76  */
77 int iotrace_get_enabled(void);
78 
79 /**
80  * iotrace_set_buffer() - Set position and size of iotrace buffer
81  *
82  * Defines where the iotrace buffer goes, and resets the output pointer to
83  * the start of the buffer.
84  *
85  * The buffer can be 0 size in which case the checksum is updated but no
86  * trace records are writen. If the buffer is exhausted, the offset will
87  * continue to increase but not new data will be written.
88  *
89  * @start: Start address of buffer
90  * @size: Size of buffer in bytes
91  */
92 void iotrace_set_buffer(ulong start, ulong size);
93 
94 /**
95  * iotrace_get_buffer() - Get buffer information
96  *
97  * @start: Returns start address of buffer
98  * @size: Returns size of buffer in bytes
99  * @offset: Returns the byte offset where the next output trace record will
100  * @count: Returns the number of trace records recorded
101  * be written (or would be if the buffer was large enough)
102  */
103 void iotrace_get_buffer(ulong *start, ulong *size, ulong *offset, ulong *count);
104 
105 #endif /* __IOTRACE_H */
106