xref: /openbmc/u-boot/common/iotrace.c (revision 7da7ff54)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2014 Google, Inc.
4  */
5 
6 #define IOTRACE_IMPL
7 
8 #include <common.h>
9 #include <mapmem.h>
10 #include <asm/io.h>
11 
12 DECLARE_GLOBAL_DATA_PTR;
13 
14 /* Support up to the machine word length for now */
15 typedef ulong iovalue_t;
16 
17 enum iotrace_flags {
18 	IOT_8 = 0,
19 	IOT_16,
20 	IOT_32,
21 
22 	IOT_READ = 0 << 3,
23 	IOT_WRITE = 1 << 3,
24 };
25 
26 /**
27  * struct iotrace_record - Holds a single I/O trace record
28  *
29  * @flags: I/O access type
30  * @timestamp: Timestamp of access
31  * @addr: Address of access
32  * @value: Value written or read
33  */
34 struct iotrace_record {
35 	enum iotrace_flags flags;
36 	u64 timestamp;
37 	phys_addr_t addr;
38 	iovalue_t value;
39 };
40 
41 /**
42  * struct iotrace - current trace status and checksum
43  *
44  * @start:	Start address of iotrace buffer
45  * @size:	Size of iotrace buffer in bytes
46  * @offset:	Current write offset into iotrace buffer
47  * @region_start: Address of IO region to trace
48  * @region_size: Size of region to trace. if 0 will trace all address space
49  * @crc32:	Current value of CRC chceksum of trace records
50  * @enabled:	true if enabled, false if disabled
51  */
52 static struct iotrace {
53 	ulong start;
54 	ulong size;
55 	ulong offset;
56 	ulong region_start;
57 	ulong region_size;
58 	u32 crc32;
59 	bool enabled;
60 } iotrace;
61 
62 static void add_record(int flags, const void *ptr, ulong value)
63 {
64 	struct iotrace_record srec, *rec = &srec;
65 
66 	/*
67 	 * We don't support iotrace before relocation. Since the trace buffer
68 	 * is set up by a command, it can't be enabled at present. To change
69 	 * this we would need to set the iotrace buffer at build-time. See
70 	 * lib/trace.c for how this might be done if you are interested.
71 	 */
72 	if (!(gd->flags & GD_FLG_RELOC) || !iotrace.enabled)
73 		return;
74 
75 	if (iotrace.region_size)
76 		if ((ulong)ptr < iotrace.region_start ||
77 		    (ulong)ptr > iotrace.region_start + iotrace.region_size)
78 			return;
79 
80 	/* Store it if there is room */
81 	if (iotrace.offset + sizeof(*rec) < iotrace.size) {
82 		rec = (struct iotrace_record *)map_sysmem(
83 					iotrace.start + iotrace.offset,
84 					sizeof(value));
85 	}
86 	rec->timestamp = timer_get_us();
87 	rec->flags = flags;
88 	rec->addr = map_to_sysmem(ptr);
89 	rec->value = value;
90 
91 	/* Update our checksum */
92 	iotrace.crc32 = crc32(iotrace.crc32, (unsigned char *)rec,
93 			      sizeof(*rec));
94 
95 	iotrace.offset += sizeof(struct iotrace_record);
96 }
97 
98 u32 iotrace_readl(const void *ptr)
99 {
100 	u32 v;
101 
102 	v = readl(ptr);
103 	add_record(IOT_32 | IOT_READ, ptr, v);
104 
105 	return v;
106 }
107 
108 void iotrace_writel(ulong value, const void *ptr)
109 {
110 	add_record(IOT_32 | IOT_WRITE, ptr, value);
111 	writel(value, ptr);
112 }
113 
114 u16 iotrace_readw(const void *ptr)
115 {
116 	u32 v;
117 
118 	v = readw(ptr);
119 	add_record(IOT_16 | IOT_READ, ptr, v);
120 
121 	return v;
122 }
123 
124 void iotrace_writew(ulong value, const void *ptr)
125 {
126 	add_record(IOT_16 | IOT_WRITE, ptr, value);
127 	writew(value, ptr);
128 }
129 
130 u8 iotrace_readb(const void *ptr)
131 {
132 	u32 v;
133 
134 	v = readb(ptr);
135 	add_record(IOT_8 | IOT_READ, ptr, v);
136 
137 	return v;
138 }
139 
140 void iotrace_writeb(ulong value, const void *ptr)
141 {
142 	add_record(IOT_8 | IOT_WRITE, ptr, value);
143 	writeb(value, ptr);
144 }
145 
146 void iotrace_reset_checksum(void)
147 {
148 	iotrace.crc32 = 0;
149 }
150 
151 u32 iotrace_get_checksum(void)
152 {
153 	return iotrace.crc32;
154 }
155 
156 void iotrace_set_region(ulong start, ulong size)
157 {
158 	iotrace.region_start = start;
159 	iotrace.region_size = size;
160 }
161 
162 void iotrace_reset_region(void)
163 {
164 	iotrace.region_start = 0;
165 	iotrace.region_size = 0;
166 }
167 
168 void iotrace_get_region(ulong *start, ulong *size)
169 {
170 	*start = iotrace.region_start;
171 	*size = iotrace.region_size;
172 }
173 
174 void iotrace_set_enabled(int enable)
175 {
176 	iotrace.enabled = enable;
177 }
178 
179 int iotrace_get_enabled(void)
180 {
181 	return iotrace.enabled;
182 }
183 
184 void iotrace_set_buffer(ulong start, ulong size)
185 {
186 	iotrace.start = start;
187 	iotrace.size = size;
188 	iotrace.offset = 0;
189 	iotrace.crc32 = 0;
190 }
191 
192 void iotrace_get_buffer(ulong *start, ulong *size, ulong *offset, ulong *count)
193 {
194 	*start = iotrace.start;
195 	*size = iotrace.size;
196 	*offset = iotrace.offset;
197 	*count = iotrace.offset / sizeof(struct iotrace_record);
198 }
199