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