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"Das U-Boot" Source Tree
1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * Copyright (c) 2012 The Chromium OS Authors.
4 */
5
6#ifndef __TRACE_H
7#define __TRACE_H
8
9/* this file is included from a tool so uses uint32_t instead of u32, etc. */
10
11enum {
12 /*
13 * This affects the granularity of our trace. We can bin function
14 * entry points into groups on the basis that functions typically
15 * have a minimum size, so entry points can't appear any closer
16 * than this to each other.
17 *
18 * The value here assumes a minimum instruction size of 4 bytes,
19 * or that instructions are 2 bytes but there are at least 2 of
20 * them in every function. Given that each function needs a call to
21 * __cyg_profile_func_enter() and __cyg_profile_func_exit() as well,
22 * we cannot have functions smaller that 16 bytes.
23 *
24 * Increasing this value reduces the number of functions we can
25 * resolve, but reduces the size of the uintptr_t array used for
26 * our function list, which is the length of the code divided by
27 * this value.
28 */
29 FUNC_SITE_SIZE = 16, /* distance between function sites */
30
31 TRACE_VERSION = 1,
32};
33
34enum trace_chunk_type {
35 TRACE_CHUNK_FUNCS,
36 TRACE_CHUNK_CALLS,
37};
38
39/* A trace record for a function, as written to the profile output file */
40struct trace_output_func {
41 uint32_t offset; /* Function offset into code */
42 uint32_t call_count; /* Number of times called */
43};
44
45/* A header at the start of the trace output buffer */
46struct trace_output_hdr {
47 enum trace_chunk_type type; /* Record type */
48 uint32_t version; /* Version (TRACE_VERSION) */
49 uint32_t rec_count; /* Number of records */
50 uint32_t spare; /* 0 */
51 uint64_t text_base; /* Value of CONFIG_TEXT_BASE */
52 uint64_t spare2; /* 0 */
53};
54
55/* Print statistics about traced function calls */
56void trace_print_stats(void);
57
58/**
59 * Dump a list of functions and call counts into a buffer
60 *
61 * Each record in the buffer is a struct trace_func_stats. The 'needed'
62 * parameter returns the number of bytes needed to complete the operation,
63 * which may be more than buff_size if your buffer is too small.
64 *
65 * @param buff Buffer in which to place data, or NULL to count size
66 * @param buff_size Size of buffer
67 * @param needed Returns number of bytes used / needed
68 * Return: 0 if ok, -1 on error (buffer exhausted)
69 */
70int trace_list_functions(void *buff, size_t buff_size, size_t *needed);
71
72/* Flags for ftrace_record */
73enum ftrace_flags {
74 FUNCF_EXIT = 0UL << 30,
75 FUNCF_ENTRY = 1UL << 30,
76 /* two more values are available */
77
78 FUNCF_TIMESTAMP_MASK = 0x3fffffff,
79};
80
81#define TRACE_CALL_TYPE(call) ((call)->flags & 0xc0000000UL)
82
83/* Information about a single function entry/exit */
84struct trace_call {
85 uint32_t func; /* Function offset */
86 uint32_t caller; /* Caller function offset */
87 uint32_t flags; /* Flags and timestamp */
88};
89
90int trace_list_calls(void *buff, size_t buff_size, size_t *needed);
91
92/**
93 * Turn function tracing on and off
94 *
95 * Don't enable trace if it has not been initialised.
96 *
97 * @param enabled 1 to enable trace, 0 to disable
98 */
99void trace_set_enabled(int enabled);
100
101int trace_early_init(void);
102
103int trace_wipe(void);
104
105/**
106 * Init the trace system
107 *
108 * This should be called after relocation with a suitably large buffer
109 * (typically as large as the U-Boot text area)
110 *
111 * @param buff Pointer to trace buffer
112 * @param buff_size Size of trace buffer
113 */
114int trace_init(void *buff, size_t buff_size);
115
116#endif