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