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