1 /*
2  * Copyright (c) 2017-2019, Arm Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <stdarg.h>
8 #include <assert.h>
9 #include <stdio.h>
10 
11 #include <common/debug.h>
12 #include <plat/common/platform.h>
13 
14 /* Set the default maximum log level to the `LOG_LEVEL` build flag */
15 static unsigned int max_log_level = LOG_LEVEL;
16 
17 /*
18  * The common log function which is invoked by TF-A code.
19  * This function should not be directly invoked and is meant to be
20  * only used by the log macros defined in debug.h. The function
21  * expects the first character in the format string to be one of the
22  * LOG_MARKER_* macros defined in debug.h.
23  */
tf_log(const char * fmt,...)24 void tf_log(const char *fmt, ...)
25 {
26 	unsigned int log_level;
27 	va_list args;
28 	const char *prefix_str;
29 
30 	/* We expect the LOG_MARKER_* macro as the first character */
31 	log_level = fmt[0];
32 
33 	/* Verify that log_level is one of LOG_MARKER_* macro defined in debug.h */
34 	assert((log_level > 0U) && (log_level <= LOG_LEVEL_VERBOSE));
35 	assert((log_level % 10U) == 0U);
36 
37 	if (log_level > max_log_level)
38 		return;
39 
40 	prefix_str = plat_log_get_prefix(log_level);
41 
42 	while (*prefix_str != '\0') {
43 		(void)putchar(*prefix_str);
44 		prefix_str++;
45 	}
46 
47 	va_start(args, fmt);
48 	(void)vprintf(fmt + 1, args);
49 	va_end(args);
50 }
51 
tf_log_newline(const char log_fmt[2])52 void tf_log_newline(const char log_fmt[2])
53 {
54 	unsigned int log_level = log_fmt[0];
55 
56 	/* Verify that log_level is one of LOG_MARKER_* macro defined in debug.h */
57 	assert((log_level > 0U) && (log_level <= LOG_LEVEL_VERBOSE));
58 	assert((log_level % 10U) == 0U);
59 
60 	if (log_level > max_log_level)
61 		return;
62 
63 	putchar('\n');
64 }
65 
66 /*
67  * The helper function to set the log level dynamically by platform. The
68  * maximum log level is determined by `LOG_LEVEL` build flag at compile time
69  * and this helper can set a lower (or equal) log level than the one at compile.
70  */
tf_log_set_max_level(unsigned int log_level)71 void tf_log_set_max_level(unsigned int log_level)
72 {
73 	assert(log_level <= LOG_LEVEL_VERBOSE);
74 	assert((log_level % 10U) == 0U);
75 
76 	/* Cap log_level to the compile time maximum. */
77 	if (log_level <= (unsigned int)LOG_LEVEL)
78 		max_log_level = log_level;
79 }
80